Effect of Transcutaneous Electro-stimulation in Ambulatory Postoperative Rehabilitation Treatment in Thoracic Surgery: Randomized Clinical Trial.
Phase: NA
Conditions: Thoracic, Postoperative Pain
Sponsor: University of Las Palmas de Gran Canaria

 
EFFECT OF TRANSCUTANEOUS 
ELECTRO-STIMULATION IN 
AMBULATORY 
POSTOPERATIVE 
REHABILITATION TREATMENT 
IN THORACIC SURGERY.       
STUDY PROTOCOL NCT04964973 
      
March 1, 2021       

STUDY PROTOCOL NCT04964973 
 
 
 
 
 
 
 
 
 
INDEX 
CONCEPTUAL FRAMEWORK. INTRODUCTION .............................................................................. 2 
ASSESSMENT OFPAIN .................................................................................................................... 2 
PAIN MANAGEMENTPOSTOPERATIVE .......................................................................................... 6 
CONTEXTUALISATION OFDOLOR ................................................................................................... 8 
PAIN ANDPHYSIOTHERAPY ............................................................................................................ 9 
ELECTRICAL STIMULATIONTRANSCUTANEOUSELECTRICAL STIMULATION ................................ 10 
DOSAGE OF TRANSCUTANEOUS ELECTRICAL STIMULATION. TENS. ....................................... 13 
RESPIRATORY CAREPOSTOPERATIVE .......................................................................................... 14 
RESPIRATORY PHYSIOTHERAPY IN THE POST-SURGICALPATIENT ........................................... 15 
PERIODPREOPERATIVE ........................................................................................................ 17 
POSTOPERATIVEPERIOD ..................................................................................................... 17 
OBJECTIVE OF PHYSIOTHERAPYRESPIRATORY ........................................................................ 18 
JUSTIFICATION ............................................................................................................................. 20 
OBJECTIVE ................................................................................................................................... 21 
HYPOTHESIS................................................................................................................................. 22 
MATERIAL ANDMETHOD ............................................................................................................. 23 
DEFINITIONOF THE STUDY ...................................................................................................... 23 
TREATMENTPHYSIOTHERAPY .................................................................................................. 24 
DATACOLLECTION ................................................................................................................... 24 
QUALITY OF LIFEASSESSMENT................................................................................................. 24 
ASSESSMENT OFPAIN .............................................................................................................. 25 
FUNCTION ASSESSMENTRESPIRATORY ................................................................................... 25 
ANALYSIS OFCOSTS.................................................................................................................. 25 
STUDYSTATISTICAL ...................................................................................................................... 26 
ANALYSISSTATISTICAL ............................................................................................................. 26 
APPLICABILITY OF RESULTS ......................................................................................................... 27 
POTENTIALPUBLICATION ............................................................................................................. 28 
RESEARCHTEAM ......................................................................................................................... 29 
WORKPLAN ................................................................................................................................. 30 
STUDYECONOMIC........................................................................................................................ 31 
BIBLIOGRAPHY ............................................................................................................................. 32 
ANNEXES .................................................................................................................................... I 

Annex 1. Quality of LifeQuestionnaireSF-36 .......................................................................... I 
Annex 2. McGillPain Questionnaire.................................................................................... VIII 

2 
 
PNEUMOCAN GRANT PROJECT 
CONCEPTUAL FRAMEWORK. 
INTRODUCTION. PAIN ASSESSMENT 
The best analgesic agent is the one that reduces pain as much as possible with the lowest 
incidence of adverse effects (1). When explaining what pain is, what is known about it and 
especially how it is evaluated in order to be able to make an adequate treatment plan within 
the intervention methodology of any health profession, it is necessary to have a correct 
knowledge of the different theories that explain pain. In this sense, there are many theories 
that have sought to explain the experience of pain. There are many branches of science that 
explain it, such as physiology, psychology and anthropology. 
 
1. Theory of pain specificity. 
 
It is one of the oldest and attempts to explain the transmission of pain. It is based on 
the concept that there is always a cause-effect relationship in the perception of pain 
(nociceptors, which project impulses onto specific pain nerve pathways). 
(A-delta (Aδ) and C-fibres) down the spinal cord to the brain). 
 
2. Pain pattern theory. 
 
This theory emerged when it was shown that nociceptors responded to stimuli such as 
pressure and temperature, not just pain. It suggests that there are no specific 
nociceptors for pain, and that these result from a combination of stimulus intensity 
and the central summation pattern of impulses in the dorsal horn of the spinal cord. 
 
3. Theory of gate control in pain perception. 
 
This theory is based on the two previous theories and is widely used in the clinic, 
although it is not fully supported by experimental evidence. It was proposed by 
Melzack and Wall in 1965. According to these authors, pain passes through a series of 
nerve pathways, through which it has to pass through gates. This theory proposes that 
pain must reach a level of consciousness before it is perceived, and if it can be 
prevented, the perception is reduced or eliminated. (2) 
 
What is important in this theory is that the closing mechanism of the various gates or 
the control of the gate can be realised in various ways: 
• 
Activation of large diameter nerve fibres. This consists of stimulating large 
diameter nerve fibres at the level of the skin (which is rich in these fibres) in 
various ways. Some examples are achieved through massage therapy, vibrotherapy 
and rhythmic rubbing. 

3 
 
• 
The generation of sensory stimuli other than pain. The brainstem reticular system 
can inhibit incoming stimuli, including pain, if the person is receiving different 
sensory stimuli, because it emits signals that close the gate. 
 
• 
Decrease unnecessary distress or depression. The gates are closed by inhibitory 
signals from the cerebral cortex and thalamus, produced by receiving appropriate 
information about the conditions that generate the painful sensation. (2) 
 
4. Endorphin and non-opioid theory of pain perception. 
 
It involves the identification of narcotic-like substances secreted by the human body 
called endorphins. These substances act by locking onto narcotic receptors on nerve 
endings in the brain and spinal cord to block the transmission of the pain signal and 
thus prevent the impulse from reaching the level of consciousness. 
 
• 
Factors that increase them: brief pain, brief stress, physical exercise, acupuncture, 
transcutaneous electrical stimulation and sexual activity. 
• 
Factors that decrease it: prolonged pain, recurrent stress, anxiety and depression 
(2). 
 
5. Opioid multi-receptor theory for pain sensation. 
 
It states that in the Central Nervous System, at the spinal and supraspinal level, 
narcotics relieve pain through various pathways, which may complement, compete or 
be specific to it. These areas are called mi, kappa and sigma. The mi receptor area 
produces supraspinal and probably spinal analgesia, respiratory depression, physical 
dependence, tolerance, constipation and euphoria. The kappa receptor zone produces 
analgesia at the spinal level, sedation, but not respiratory depression or physical 
dependence, and the sigma receptor zone produces vasomotor stimulation and 
possible psychostimulant effects (hallucinations) (2). 
 
6. Psychological theory of pain. 
 
Human behaviour is the main part of this theory. For this theory, pain is an abstract 
concept, which refers to a personal and private sensation of harm and, rather than a 
sensation, it is an unpleasant emotional experience, which is best defined as the 
awareness of a state of need. (2) 
 
After the above, a specific approach is made to the assessment of pain from the point of view 
of physiotherapy. Pain is not an easy sensation or situation to analyse, evaluate and 
consequently treat. The treatment of pain, both as a symptom and as a problem, must be 
approached and dealt with as scientifically and objectively as possible. Therefore, the 
necessary measures are developed to exercise this professional power. 

4 
 
The main problem is the conversion of an absolutely subjective problem into an objective one. 
The different levels of action, previously developed by authors such as Tomas Gallego in his 
book Bases teóricas y fundamentos de la Fisioterapia (Theoretical bases and foundations of 
physiotherapy), are developed below. 
Pain measurement methods 
 
We will define three ways to measure pain: 
 
- 
Verbal methods. 
 
- 
Behavioural assessments. 
 
- 
Physiological measures. 
 
 
 
Verbal methods. 
 
- 
Clinical interview. Its purpose is to approach the sensory aspects of pain. It is used to 
measure chronic pain. Data will be collected in relation to: 
o Chronology in the patient's history. Age, form of onset, evolution, treatments 
carried out, circadian rhythm throughout the day. 
 
o Localisation on the body schema. 
 
o Characteristics of pain: intensity, qualities. 
 
o Pain behaviours. Pain-informed behaviours, maladaptive behaviours, 
reinforced by the environment. 
 
- 
Self-reports. They measure sensory aspects of pain. Simple instruments used to assess 
acute pain. The visual analogue scale (VAS) is the best known. 
 
- 
Standardised tests. The McGill questionnaire is the most widely used, measuring 
sensory, affective and behavioural aspects (3). 
 
Behavioural assessments. 
 
Its function is to assess how personality influences the manifestation of pain, it attempts to 
discern when suffering is caused by pain and when it is caused by the personality of each 
patient. The Minnesota Multiphasic Personality Inventory (MMPI) is the most commonly used 
and considered the most valid scale. 
 
Physiological measures. 
 
The measurement of a physiological process involved in pain could provide objective evidence 
that would allow great advances in the study of this field. Aspects such as electromyography, 
electroencephalography, heart rate, autonomic indices, etc. could be measured. 

5 
 
(heart rate, blood pressure, body temperature, skin conductance), evoked potentials 
and others are studied in this section (3). 

6 
 
POSTOPERATIVE PAIN MANAGEMENT 
Inadequate perioperative pain control causes serious medical complications, prolonged 
hospital stay and unnecessary suffering. For this reason, it is important to implement the best 
management strategies (1). 
 
Pain has a subjective and individual part, which is influenced by emotional factors, personality, 
socio-cultural aspects, as well as the patient's previous experience with pain. However, it is 
clear that there is also an objective part. It has been demonstrated that poor pain control 
increases the patient's morbidity, as it acts on all systems: at the cardiovascular level, intense 
pain releases catecholamines, which can cause arterial hypertension, arrhythmias and even 
shock; at the respiratory level, it decreases lung function and increases oxygen consumption, 
as well as decreasing intestinal motility and making urination difficult. It also produces other 
less serious but equally important disorders, such as anxiety, insomnia and hormonal 
stimulation (4). 
 
One of the main fears that patients express before undergoing surgery is the pain that 
surrounds the whole surgical process, a fear that is justified if we take into account that: 
 
- 
The pain that can be caused by the healthcare activity itself through the use of drains, 
lines, catheters and postural changes, among others, is often overlooked. 
 
- 
Lack of standardisation in pain records, occurrence, intensity, measures taken to 
reduce pain (4). 
 
- 
Lack of knowledge on the part of the personnel responsible for the care of the post- 
surgical patient of the physiopathology of pain, the pharmacology of the various 
analgesics and psychological factors that affect pain (4) (5). 
 
- 
Post-surgical pain is not given the necessary importance, and this is perhaps the most 
important point. 
 
The above can be summarised by stating that post-surgical pain is an acute pain, with 
exacerbation of emotional and perceptual experiences that will be associated with autonomic 
and psychological reflex responses. 
 
Pain associated with wounds imposes activity limitations and thus prevents aggravation of the 
pathology causing the pain. Acute postoperative pain has no useful function and if unrelieved 
will produce abnormal physiological and psychological responses that often cause 
complications. These responses are classified as: 
 
1- Segmental responses. 
 
2- Suprasegmental responses. 
 
3- Cortical responses. 
 
 
 
Segmental responses. 

7 
 
These are reflex responses that cause an increase in skeletal muscle function, which may result 
in a decrease in chest wall compliance. Stimulation of preganglionic sympathetic neurons in 
the anterolateral horn of the spinal cord results: 
 
- 
Increased cardiac output. 
 
- 
Increased myocardial O2 consumption. 
 
- 
Vasoconstriction 
segmental 
which can 
decrease 
the function urinary 
and gastrointestinal function, favouring the development of paralytic ileus. (5). 
 
Suprasegmental responses. 
 
They result from the stimulation of respiratory and cardiovascular spinal centres which can 
cause: 
- 
Hyperventilation. 
 
- 
Increased sympathetic tone. 
 
- 
Increased secretion of catecholamines, cortisol, ACTH, glucagon and other catabolic 
hormones (5). 
 
If segmental responses are added to the above, higher cardiac output and increased peripheral 
vascular resistances are evident, resulting in increased blood pressure and thus a generalised 
increase in O consumption2 . 
 
Metabolic responses include: 
 
- 
Increased plasma glucose level. 
 
- 
Increase in cyclic AMP. 
 
- 
Increased free fatty acids, lactates and ketones 
 
- 
Widespread increase in basal metabolism (5) 
 
With all this, the patient tends towards a negative nitrogen balance. 
Cortical responses 
These responses include not only the perception of pain as an unpleasant sensation, but also 
the initiation of dynamic mechanisms such as anxiety, apprehension and fear (5). 
 
Acute postoperative pain is pain that occurs when a patient undergoes surgery, either 
associated with the surgical procedure and the pre-existing disease or a combination of both 
(1). 

8 
 
For proper postoperative pain control, effective and safe analgesic management during the 
perioperative period (preoperative, intraoperative and postoperative) should be carried out, as 
well as to avoid future sequelae. Specifically, this involves: 
 
1. Minimise the incidence and severity of acute perioperative pain. 
 
2. Educate patients and their families about the importance of their involvement in 
effective pain management. 
 
3. Improving patient wellbeing. 
 
4. To reduce postoperative complications secondary to pain management and, as far as 
possible, the length of hospital stay (1). 
 
 
CONTEXTUALISATION OF PAIN 
Pain following thoracic surgery has a number of particular characteristics: 
 
- 
It is considered the most severe acute postoperative pain. 
 
- 
Theinadequate 
 
 control 
of 
pain 
favours 
the 
occurrence 
of 
serious postoperative complications such as atelectasis and 
respiratory infections. 
- 
Adequate relief allows for intensive physiotherapy, reducing the occurrence of such 
complications. 
 
- 
Functional residual capacity (FRC) decreases (6). 
 
Several mechanisms are involved in the aetiopathogenesis of this pain, including the following: 
 
- 
Surgical incision. 
 
- 
Lung resection. 
 
- 
Pleural drainage tubes. 
 
- 
Inflammation. 
 
- 
Injury to intercostal nerve or costal spinal roots (6) 
 
Potential problems may also arise, such as limitation of movement in the upper limbs and rib 
cage, muscle shortening (derived from the surgical act itself) and the consequent reduction in 
joint range (7). 

9 
 
PAIN AND PHYSIOTHERAPY 
In accordance with the concept of Science, defined by the Royal Academy of the Spanish 
Language as "a methodically formed and ordered body of doctrine that constitutes a particular 
branch of human knowledge", in order to describe, interpret and analyse how Physiotherapy as 
a Science approaches pain, it is necessary to describe and deepen the concept of pain from the 
point of view of Physiotherapy. 3In order to describe, interpret and analyse how Physiotherapy 
as a Science approaches pain, it is necessary to describe and analyse the concept of pain from 
the point of view of Physiotherapy. 
 
There are three types of pain from a physiotherapy point of view: 
 
a. Pain of biochemical origin. 
 
b. Pain of neuralgic origin. 
 
c. Pain of mechanical origin. 
 
Biochemical pain results from local metabolic and electrochemical disturbances due to acute 
inflammation, tissue tears and vascular ruptures. It consists of the irritation of abnormal nerve 
endings due to oversaturation of unusual substances, which are intended to be eliminated. 
Within the physiotherapeutic examination, it would be those pains that appear on tissue 
palpation. The visual appearance is usually accompanied by redness. Touch is used to detect 
heat radiation if the inflammation is acute, or crusting and induration if the process is chronic. 
 
Pain of neuralgic origin is that which appears when a nerve root is damaged, pinched or 
demyelinated in its pathway, with the fundamental characteristic that it reflects in its area of 
innervation: tingling, numbness, pain and neurovegetative, sensory and motor insufficiency. Its 
most frequent manifestation is radiating pain, with a trajectory, deep localisation, it is not 
palpable, it manifests itself both in activity and at rest, it is accentuated in certain postures and 
relieved in others. If the neuralgic pain is acute, it has the characteristic of being able to cause 
functional impotence and large defence contractures. 
 
When there is excessive compression of a structure, excessive elongation in a tissue or group 
of tissues or permanent crushing, mechanical pain is defined. It is caused by 
mechanoreceptors, which report aggression instead of normal proprioception (8). 

10 
 
TRANSCUTANEOUS ELECTRICAL STIMULATION 
In 2010, J.J. Amer-Cuenca published a scientific article in the journal "Fisioterapia" with the 
following title: "Programming and application of transcutaneous electrical nerve stimulation 
(TENS): evidence-based clinical practice guide". The beginning of this article is literally: 
"Transcutaneous electrical nerve stimulation, known by the acronym TENS, consists of the 
application, by means of surface electrodes, of pulsed electrical current for analgesic purposes. 
The current use of TENS in the clinical field of physiotherapy is very widespread. It can be said 
that, together with interferential stimulation, it is the most widely used electrical stimulation 
technique as an alternative to traditional analgesic treatments, such as pharmacological or 
surgical treatments. Its popularity is based, among other aspects, on the fact that it is a non- 
invasive technique, easy to administer, has few side effects and interactions with other drugs, 
cannot produce overdoses, and is a very economical technique that can be used for home 
treatment after a period of training of the patient himself". (9) 
 
Similarly, this author draws the following analogy: "...to point out the proper selection of 
parameters, the characteristics of the electrical impulse (shape, duration, frequency) would be 
the active element of TENS therapy, just as the chemical components are the active element of 
a drug. In addition to the proper selection of the parameters, the correct dosage and 
application of the parameters (intensity, size and placement of the electrodes, as well as the 
mode of stimulation) is fundamental. The effectiveness of TENS treatment depends on the 
correct combination of all these elements". (9) 
 
The conclusions reached by this author in his research are as follows: 
 
• 
The waveform shall be a symmetrical, compensated pulsed two-phase pulsed pulse. 
• 
The pulse duration must be greater than 250µs. 
• 
The application frequency should be high (greater than 80 Hz). 
• 
The size of the electrodes should be large. 
• 
Electrodes placed directly on the area of pain or corresponding dermatomas. 
• 
The intensity should be as high as possible without causing pain (9). 
Reviewing the history of the relationship between physiotherapy-pain-transcutaneous 
electrical stimulation, in 1997, Fabrizio Benedetti et al., after carrying out a study on 324 
patients who underwent surgery for various procedures: posterolateral thoracotomies, 
thoracotomies with muscle transposition, costotomies, stereotomies, thoracoscopies, 
demonstrated that the application of TENS was effective in operations with little pain and did 
not demonstrate effectiveness in pain control in patients who underwent operations 
considered to be painful. 
 
This dichotomous model differentiates between the different levels of pain patients undergo 
following this surgery. This work used three groups of patients: 

11 
 
1. First group to receive TENS with high-frequency stimulation, with an asymmetric wave 
type, 100 Hertz frequency and phase duration of 200 µs. 
2. The second group, placebo group, was given the same treatment, but in this group the 
TENS was applied without batteries. 
3. Third or control group that received conventional pharmacology to control pain (10). 
 
Later, V.M. Rocha et al. in their article "Behaviour of pain and the use of neurotranscutaneous 
electrical stimulation in the postoperative period after thoracic surgery", introduced the use of 
the Gill pain questionnaire as a novelty and analysed the amount of medication consumed by 
patients on the second, third and fourth postoperative day. In his discussion he comments that 
the surgical incision, especially the thoracic incision, leads patients to avoid coughing and deep 
breathing, which leads to a decrease in vital capacity and functional residual capacity. 
 
It also indicates in its conclusions that TENS is proven to be an effective antalgic and auxiliary 
tool for physiotherapeutic procedures. In other words, it reduces the painful stimulus caused 
by surgical trauma, as well as those caused by mobilisation of the patient in the postoperative 
period (11). 
 
In 2003, Jan Magnus Bjordal and his collaborators established satisfactory results in the 
application of TENS after surgery, not referring specifically to thoracic surgery. They also 
establish 85 hertz as the ideal frequency (12). 
In 2008, Chih-Chung Chen together with Ghazala Tabasam and Mark I. Johnson in their article 
"Does pulse frequency of transcutaneous electrical nerve stimulation (TENS) influence 
hypoalgesia? A systematic review of studies using experimental pain in healthy human 
participants", they conducted a systematic review of thirteen experimental studies from 
twelve publications. Of these thirteen studies, ten show no significant differences between 
different frequencies, although one of them does show significant differences indicating that 
100 Hertz per second is more hypoalgesic than 10 Hertz per second. In another, the frequency 
of 4 Hertz per second was superior in its analgesic effect to 100 Hertz. In the last one, it was 
shown that frequencies between 5 and 80 hz were more hypoalgesic than 2 hz. In view of the 
above, he concludes that frequency is not a determining factor when the intensity, pattern and 
duration of the phase are constant (13). 
 
This aspect of TENS application has an influence not only on the field in which this work is 
carried out. In chronic muscle pain, TENS has developed as an important agent of analgesia by 
stimulation of opioid receptors (14). 
 
In this regard, significant differences have been found in various physical therapy treatments 
comparing TENS with other procedures such as massage (15). 
 
Its effectiveness has also been demonstrated in the treatment of degenerative pathologies as 
shown by Luis Gerardo Domínguez-Carrillo (2001) (16). 

12 
 
In 2009, Anne Freynet and Pierre-Emmanuel Falcoz reviewed nine papers published between 
1980 and 2007. In their conclusions they indicate that in seven of the nine studies TENS is used 
as an adjuvant to analgesic medication. Significant differences in pulmonary ventilation are 
thus demonstrated (17). 
 
Fabiana Cristina Ferreira and her colleagues later carried out a study in 2011 with thirty 
patients who had undergone lung cancer surgery and tested the effect of the application of 
TENS. They formed two groups and applied TENS to one of them, using the other group as a 
control group. Their results show a significant analgesic effect with the patient at rest, with this 
effect diminishing when the patients are asked to raise their upper limbs, move from supine to 
lateral decubitus or cough (18). 
 
In July 2011, D. Groppetti and colleagues published the paper: Effectiveness of 
electroacupuncture analgesia compared with opioid administration in a dog model: a pilot 
study. This study concludes that the results obtained from this research show evidence that 
electroacupuncture is an alternative technique to achieve postoperative analgesia in dogs (19). 

13 
 
DOSAGE OF TRANSCUTANEOUS ELECTRICAL STIMULATION. TENS. 
From another point of view, it has been studied since 1981 that the frequency of TENS, high or 
low, works in different ways. In several studies and publications, Sluka analyses how TENS acts 
from a biochemical point of view, acting on different opioid receptors. Thus, in his article 
"Spinal Blockade of opioid receptors prevents the analgesia produced by TENS in arthritic rats", 
he states that Abrahams et al. have already studied the effects of high frequency and proposed 
that this mode of application produces analgesia based on the Control Gate Theory. In 
contrast, Sjond and Erikson propose that low frequency TENS derives its effect from opioid 
release (20). 
Therefore, high frequency causes analgesia during its application while low frequency causes 
longer lasting analgesia. That is, the effect of high frequency is mediated by δ opioid receptors, 
whereas low frequency will be influenced by µ opioid receptors (20). 
 
In another paper, Campbel and Tamb (1973), define that the control gate theory could be used 
to explain the actions of high frequency TENS application, although they also suggest that high 
frequency blocks nociceptive conduction through δ receptors. 
 
The release of endogenous opioids is used to explain the action of low frequencies. This is 
explained in humans by the use of the opioid receptor antagonist naloxone at low frequency 
application, which is not the case at high frequency. However, high-frequency stimulation is 
inhibited by high-dose naloxone administration in rats or spinal administration of a selective δ- 
receptor antagonist. 
 
Similarly, high frequency increases the concentration of β-endorphins in cerebrospinal fluid in 
humans. These results are probably obtained by the different modalities of TENS application 
according to their frequency (21). 
 
From 2005 onwards, the greatest research activity in this aspect of defining TENS and its 
analgesic capabilities was developed. Sluka establishes the appropriate analysis and the 
necessary research that generates a revolution in this therapy modality. In this period, TENS 
(Transcutaneous electrical nerve stimulation) was defined as the most commonly used non- 
pharmacological treatment for the treatment of pain. (22) In this article, two different 
frequencies were evaluated for TENS, 4 Hz and 100 Hz, demonstrating that the high frequency 
and not the low frequency significantly reduced the level of aspartate and glutamate in 
animals with joint inflammation. 

14 
 
POSTOPERATIVE RESPIRATORY CARE 
There are several respiratory cares that should be performed in every post-surgical patient, 
among them are the following: 
 
1. Effective analgesia, being essential the complete elimination of pain to facilitate the 
elimination of secretions and to be able to carry out effective Respiratory 
Physiotherapy. 
2. Oxygen therapy is administered to treat or prevent hypoxaemia, without influencing 
airspace abnormalities. 
3. Humidification and aerosol treatment, secretions are easier to mobilise if they are 
moist. Ciliary function is depressed in contact with dry gas. 
 
4. Pharmacological support. Drugs may be administered to facilitate secretion clearance, 
increase airway calibre or support the cilia expulsion mechanism. 
 
5. Respiratory physiotherapy manoeuvres are aimed at promoting thoracic expansion 
and increasing the elimination of secretions, thus counteracting the aforementioned 
facts that can lead to a decrease in lung volumes. (23) 

15 
 
RESPIRATORY PHYSIOTHERAPY IN THE POST-SURGICAL PATIENT 
The existence of pulmonary dysfunction is a constant occurrence after abdominal and thoracic 
major surgery, with these groups of patients presenting between 20% and 40% of 
postoperative pulmonary complications depending on the series, with a mortality of 16% after 
the appearance of these complications, being the main cause of morbidity and mortality(23) . 
One of the important problems after this type of intervention is the reflex inhibition of the 
phrenic nerve and the decrease in diaphragmatic activity. As a consequence of this process, 
lung expansion is neither complete nor homogeneous, which favours the presence of 
pulmonary atelectasis24 . 
This pulmonary dysfunction is mainly caused by the immediate postoperative process and 
changes in lung function. We can list them as follows: 
1. Modifications of respiratory mechanics. 
 
2. Modifications of the respiratory pattern. 
 
3. Modification of gas exchange. 
 
4. Modification of defence mechanisms. 
 
5. Diaphragmatic dyskinesia (23) 
Modification of respiratory mechanics 
A restrictive problem usually appears, leading to a decrease in lung volumes, with functional 
residual capacity being reduced by up to 75% or more compared to normal values. The forced 
vital capacity (FVC) of peak expiratory flow (FEV1) shows average decreases of 40-50% with 
respect to preoperative values. This decrease in lung volumes increases progressively during 
the first 24-48 hours of the immediate postoperative period. Return to preoperative values 
takes 1-2 weeks. 
Modification of the breathing pattern 
 
There is also a change in the respiratory pattern. Pain is possibly the main cause, hence all 
measures aimed at abolishing it during this period. The minute volume is modified, as there is 
an increase in respiratory frequency which tends to compensate for the decrease in tidal 
volume that occurs. The second modification observed corresponds to the deep inspirations or 
sighs that have been abolished. In normal subjects, 9-10 sighs/minute are performed. During 
the immediate postoperative period, if they exist, they are frequent but of a small amplitude. 
Moreover, it should be noted that they disappear completely after the administration of 
morphine. This monotonous, shallow breathing without sighs leads to lung collapse and a 
decrease in functional residual capacity (FRC). 

16 
 
Modification of gas exchange 
 
The changes described above lead to the appearance of alveolar collapse with decreased 
ventilation in certain alveolar territories. If perfusion in these territories is maintained, the 
blood in these alveolar territories will not be oxygenated, creating a right-to-left pulmonary 
short-circuit. In the less ventilated territories, oxygenation will be partial. These changes lead 
to the appearance of hypoxaemia, a constant phenomenon in the postoperative period, with a 
systematic decrease of 10%-20% with respect to baseline values after abdominal and thoracic 
surgery. 
 
Modification of defence mechanisms 
 
The lung's defence mechanisms against inhalation of particles or infection are also modified. 
Coughing is the main defence mechanism, as it produces both an inspiration and a large 
exhalation. The ability to cough and clear secretions is impaired by reduced inspiratory and 
expiratory reserve capacity. Coughing is inhibited during this period by the pain it produces. 
 
Diaphragmatic dyskinesia 
 
The aforementioned modification of the respiratory pattern would be explained by a decrease 
in the abdominal diaphragmatic component, with recruitment of the intercostal muscles as a 
manifestation of diaphragmatic dysfunction. 
The most likely mechanism to explain this alteration would be reflex inhibition of phrenic 
impulses, which does not seem to be linked to pain, as studies with morphine analgesia via 
thoracic epidural show that diaphragmatic function is not improved, although there is a slight 
increase when local anaesthetics are administered via this route (23). 
Numerous authors agree on the validity of slow and deep inspiratory manoeuvres, the 
coughing technique with wound restraint and incentive spirometry to prevent respiratory 
complications (24). 
 
In May 2006, a study was carried out at the Carlos Haya Hospital in Malaga on which type of 
physiotherapy is more effective in patients undergoing upper abdominal surgery. The aim of 
the study was to compare classic respiratory physiotherapy with classic respiratory 
physiotherapy plus incentive spirometry in the preoperative period for these patients. The 
variables studied were as follows: 
 
- 
Spirometry; in particular forced vital capacity (FVC), maximal exhaled volume in the 
first second (FEV1 or VEMS) and the FEV ratio1 /FVC (FEV1 ). 
 
- 
The six-minute test marches on. 
 
- 
Thoracometry. The upper, middle and lower circumferences were measured with a tape 
measure. 
 
- 
Respiratory frequency. 
 
The most characteristic feature of this study was that classic respiratory physiotherapy proved 
to be more effective than the latter plus incentive spirometry, with the lower perimeter of the 

17 
 
lower respiratory tract being more effective than the latter plus incentive spirometry. 

18 
 
The treatment was intended to help the patient learn to mobilise the diaphragm as widely as 
possible by means of deep inhalations, so that after the operation the patient could begin to 
do so as soon as possible in order to avoid postoperative complications. (24) 
 
The postoperative length of stay of patients who have undergone thoracic surgery depends 
mainly on the duration of the pleural drainage and the presence of possible complications. 
Respiratory physiotherapy is one of the existing resources that can reduce this parameter. It is 
not yet fully implemented in all units, although it is increasingly used and is in full expansion. 
Correct pain control is essential for the correct application of physiotherapeutic procedures 
(11). 
 
PREOPERATIVE PERIOD 
Pre-operative problems that may negatively influence secretion clearance include advanced 
age, impaired general condition with inability to cough, presence of COPD with increased 
expectoration production and/or decreased FVC, asthmatic bronchitis, upper airway 
abnormalities, and altered gag or cough reflexes. 
 
Respiratory care should be initiated in the preoperative period by identifying patients at risk 
for respiratory complications and initiating treatment of reversible factors that may respond to 
treatment (23). 
 
POSTOPERATIVE PERIOD 
The primary goal after thoracic surgery is to restore lung expansion and facilitate clearance of 
secretions. Patients should leave the operating theatre extubated. Unless there are specific 
contraindications, intubated patients are positioned with the head at 30° to improve functional 
residual capacity (FRC), facilitating diaphragmatic mobility and shifting the weight of the 
abdominal viscera away from the lung bases. Aerosols with mucolytic drugs can be prescribed, 
to which bronchodilators can be added, depending on the patient's clinical situation. Chest 
expansion is achieved by scheduled sessions of manual ventilation (with ambu) and by adding 
sighs to mechanical ventilation. 
 
Once extubated, patients are kept in the 30° position and oxygen therapy is administered as 
needed, with effective analgesia being particularly important in order to initiate deep breaths 
and mobilise the diaphragm. Aerosols are also started in order to humidify secretions and 
facilitate their expulsion. In the first few hours, coughing should not be forced, as it is usually 
ineffective and exhausts the patient. The secretions, once humidified, are easily mobilised and 
expelled from the bronchial tree. Early mobilisation should be performed (before 24 hours), if 
the clinical situation permits, as this mobilises all lung areas, improving areas with a poor 
ventilation/perfusion ratio and facilitating the mobilisation and expulsion of secretions. (23) 

19 
 
OBJECTIVE OF RESPIRATORY PHYSIOTHERAPY 
The American Thoracic Society (ATS) defined respiratory rehabilitation as a multidisciplinary 
programme of care for patients with chronic respiratory impairment that is individually 
tailored and designed to optimise their physical and social performance and autonomy (25). 
 
The aim of respiratory rehabilitation will be divided into several stages: 
 
a. Bringing the patient to maximum physical potential. 
 
b. To bring the patient to his or her full mental, emotional, social and vocational potential. 
 
c. To reduce symptoms and pathophysiological consequences of respiratory impairment. 
 
d. Decrease the degree of physical incapacity (11) 
 
Within the types of intervention that describe the processes of surgical intervention in 
Thoracic Surgery, the following are described: 
 
1. Posterolateral thoracotomy. This is the most painful of all surgical procedures due to 
its high muscular involvement, with resection of the trapezius, latissimus dorsi, the 
lower portion of the rhomboids, the serratus anterior, the intercostals and the erector 
spinae. 
 
2. Axillary thoracotomy, often referred to as lateral thoracotomy, used in uncomplicated 
surgery. Only the intercostal muscles are sectioned. 
3. Median sternotomy, used for resection of anterior mediastinal tumours (26). 
 
4. Videothoracoscopy, currently widely used for pleural, pulmonary and mediastinal 
interventions. One to three incisions of about 2 cm and sometimes an auxiliary 
thoracotomy of about 5 cm are made. 
 
A pulmonary complication is defined as any pulmonary abnormality occurring during the 
postoperative period that results in identifiable and clinically significant dysfunction, which 
adversely affects the clinical course. (26) These are the most common. 
These complications are set out in: 
 
1. Auscultation changes (decreased breath sounds, crackles, wheezing, bronchial 
breathing) greater than those present before surgery. 
 
2. Temperature over 38°. 
 
3. Chest x-ray with changes consistent with collapse, consolidation or atelectasis. 
 
4. Increase in the amount and/or change in colour of sputum production, compared to 
the patient's usual sputum (26). 

20 
 
Thoracic surgery has a high incidence of complications. The most frequent are atelectasis and 
respiratory infections, especially pneumonia. Other complications also include arrhythmias, 
hypotension and shock, myocardial infarction, pulmonary oedema and embolism, respiratory 
failure, prolonged air leaks and dehiscence, among others (26). 
 
The principles which, in principle, apply are: 
 
1. To achieve effective analgesia in order to be able to perform efficient respiratory 
physiotherapy. Physiotherapy manoeuvres should always be started after the absence 
of pain has been achieved. 
 
2. Oxygen therapy, to prevent hypoxaemia. 
 
3. Humidification and aerosol treatment. Its main purpose is to fluidise sputum, humidify 
the airway, mobilise secretions and administer drugs by inhalation. 
 
4. Pharmacological treatment, in order to clear secretions, increase airway calibre or 
support the cilia expulsion mechanism. 
5. Respiratory physiotherapy, with manoeuvres aimed at promoting thoracic expansion 
and the elimination of secretions. The following manoeuvres are basic: 
 
a. Diaphragmatic mobilisation. 
 
b. Hyperinflation or thoracic expansion therapy. 
 
c. Postural drainage. 
 
The primary goal of respiratory rehabilitation after chest surgery is to bring the patient to 
maximum physical potential, as well as to reduce symptoms and pathophysiological 
consequences of respiratory impairment (23). 
 
Respiratory physiotherapy is essential to achieve thoracic expansion and diaphragmatic 
mobilisation, avoid diaphragmatic dysfunction and reduce the occurrence of atelectasis and 
respiratory infections. It should be accompanied by intense analgesia with as few side effects 
as possible. 
 
The aim of this study focuses on the need, through physiotherapeutic means, to achieve the 
highest possible level of analgesia for these patients without generating morbidity. 

21 
 
JUSTIFICATION 
One of the fundamental bases of physiotherapy is the intervention in pain control. Post- 
surgical pain in thoracic surgery is considered to be one of the most intense pains that exist. 
Based on this principle, the aim of this work is to demonstrate that pain control, recovery, 
readaptation and development of respiratory parameters are normalised with greater 
precision and in less time. 

22 
 
OBJECTIVE 
The objective of the present study, in accordance with the hypothesis determined, will be to 
demonstrate four points relating to the activity of physiotherapy. These points will be the 
following: 
1. Physiotherapy techniques are an effective element of pain control in the postoperative 
chest surgery patient. 
 
2. The quality of life of postoperative chest surgery patients improves with the 
application of analgesic physiotherapy techniques. 
 
3. Respiratory parameters improve in a shorter time if pain control is carried out during 
respiratory physiotherapy sessions. 
 
4. As a result, the healthcare expenditure involved in caring for these patients decreases 
considerably. 
The objectives of this work are therefore defined as follows: 
 
Objective one: To demonstrate that physical pain control using transcutaneous 
electrostimulation (TENS) results in effective physiotherapy for the improvement of respiratory 
capacities. 
 
Objective two: To demonstrate that improvement in respiratory capacity improves patients' 
quality of life. 
Objective three: To demonstrate that effective physiotherapy results in less time spent in 
outpatient care, leading to a reduction in the case-mix of rehabilitation and a reduction in the 
health care costs associated with this intervention. 

23 
 
HYPOTHESIS 
Physical pain control using transcutaneous electrostimulation (TENS) in patients who have 
undergone chest surgery allows effective physiotherapy that improves respiratory capacity and 
quality of life and reduces health care costs. 

24 
 
 
MATERIAL AND METHOD 
DEFINITION OF THE STUDY 
This is a prospective, randomised study in which the aim is to study the value of an analgesic 
technique (TENS). The study will be carried out on patients undergoing thoracic surgery for 
pleural, pulmonary or mediastinal procedures of varying complexity. Patients will be recruited 
once the immediate postoperative period has passed, with a deadline of 7 days after the 
operation for inclusion in the study. There will be three groups of patients: 
 
Group 1.- Patients treated with anterior, lateral or axillary thoracotomy. 
 
Group 2.- Patients treated with videothoracoscopy with three or more entry doors and/or with 
mini-thoracotomy assistance. 
 
Group 3.- Patients treated with videothoracoscopy with one or two entry doors. 
Inclusion criteria 
Patients treated with each of the interventions described and who are between 18 and 80 years 
of age. 
 
Signed informed consent to participate in the study. Exclusion 
 
criteria 
 
Patients operated by any approach other than those described above (median sternotomy, 
chest wall resection, extended posterolateral thoracotomy, cervical incisions, major chest wall 
surgery or chest wall deformities). 
Patients with pacemakers or other devices that may interfere with the use of TENS. 
 
Patients with chronic diseases requiring the use of corticosteroids or analgesics on a regular 
basis. 
Patients with a history of drug dependence. 
 
Patients with postoperative complications requiring hospital admission. 
 
Patients requiring maintenance of postoperative pleural drainage. 
 
Those patients who meet the inclusion criteria will be recruited, 
depending on the intervention performed, into one of the three groups 
referred to. Each of the groups will be divided into two, randomising the 
patients with random numbers to assign them to one of the three groups. 
Figure 1. 

25 
 
to each of the subgroups depending on whether TENS therapy is applied. Each group will 
therefore have two subgroups: a (TENS subgroup); b (control subgroup with conventional 
therapy). 
 
PHYSIOTHERAPEUTIC TREATMENT 
The treatment to be carried out does not differ from that usually carried out in these patients. 
Therefore, in the control subgroups, treatment will be carried out by means of respiratory 
physiotherapy and rehabilitation of the thoracic musculature. 
In the TENS subgroups (study group), the specific physiotherapy technique for pain control (using 
transcutaneous electrical stimulation) will be performed. This technique will consist of the 
application of TENS (figures 1 and 2) using the 
gate-control theory. For this, we will place two electrodes on both 
sides of the surgical incision, with the negative electrode being the 
one furthest from the neural tube and the positive electrode being 
the most proximal. The application frequency will be 100 Hz (22), 
the intensity of the application will be that which the patient can 
bear, the application time will be the same as the duration of the 
Respiratory Physiotherapy session. The pattern of respiratory 
physiotherapy will be the same, the treatment will not be 
modified in any of its stages. 
Figure 2. 
 
DATA COLLECTION 
All patients likely to be included in the study will undergo a thorough medical history. This 
medical history will be based on the following aspects: 
- 
Details of affiliation. 
 
- 
Personal background. 
 
- 
Type of intervention carried out. 
 
- 
Incisions made. 
 
- 
Chronology, location and characteristics of pain. 
 
Once the patient has undergone surgery, the data corresponding to the surgical intervention 
performed will be collected. Once the period of 7 days has elapsed after the operation and in 
the absence of complications and pleural drainage, the period of respiratory physiotherapy will 
begin. 
 
QUALITY OF LIFE ASSESSMENT 
The health questionnaire SF-36 (Short Form Health Survey) will be used. This questionnaire is 
used in medical research, mental health research and health-related research in general. It 
provides an overview of a person's state of health, with the advantage that it is easy and quick 
to fill in and simple to evaluate. Similarly, by allowing numerical assessment of different 
aspects of a person's health, it can be used to assess the health status of the individual. 

26 
 
The questionnaire is an excellent tool for any health-related research. It contains 36 questions 
that address different aspects related to the daily life of the person filling in the questionnaire. 
These questions are grouped and measured in 8 sections that are assessed independently and 
give rise to 8 dimensions measured by the questionnaire. 
 
The eight dimensions are: 
 
1. Physical functioning. 
2. Limitation due to physical problems. 
3. Body pain. 
4. Functioning or social role. 
5. Mental health. 
6. Limitation due to emotional problems. 
7. Vitality energy or fatigue. 
8. General perception of health. (Annex 1). 
 
In 1991, the International Quality of Life Assessment Project (IQOLA) was initiated, consisting 
mainly of adapting and testing the cross-cultural applicability of a generic instrument called the 
Short Form 36 Health Survey (SF-36) (27). 
 
The Spanish version of the SF-36 is one of the most widely used generic instruments in Spain, 
both in descriptive studies that measure the impact on HRQOL in different patient populations 
and for the evaluation of therapeutic interventions (28). 
 
PAIN ASSESSMENT 
The tools necessary to make a correct assessment of pain. In this sense, two ways of 
measuring pain will be established: 
 
1. Self-reports, where the visual analogue scale (VAS) will be the basic measurement 
tool. Pain will be marked on a scale from 0 (no pain) to 10 (maximum possible pain). 
2. The standardised tests, as an objective of the study, also aim to analyse sensory, 
affective and behavioural aspects of pain in these patients, which is why the Mc Gill 
test will be the tool to be taken into account (Appendix 2). 
 
ASSESSMENT OF RESPIRATORY FUNCTION 
The different respiratory parameters will be measured by spirometry (Siebel spirometer): 
Forced Vital Capacity (FVC); Forced Expiratory Volume of the first second (FEV1 ); FEV1/FVC 
(Tiffeneau Index). 
 
COST ANALYSIS 
Activity times shall be measured in two groups of patients. In all cases, the recovery time and 
return to normal life will be established. A study of the costs of visits and physiotherapy 
treatment of these patients until their return to normality prior to the intervention will be 
carried out. 

27 
 
STATISTICAL STUDY 
Data collection will be carried out over a period of three years. There are no reliable data to 
allow statistical calculation of the sample size, but it is estimated that 30 patients are needed 
for each of the subgroups described, giving a total sample size of 180 patients. 
 
This is a prospective, randomised, longitudinal study. 
 
STATISTICAL ANALYSIS 
 
Quantitative variables will be described by means of centralisation and dispersion indices: 
mean, standard deviation and range. The hypothesis of normality of the variables will be 
verified using the Kolmogorov-Smirnov test for a single sample. Qualitative variables will be 
treated by analysing the absolute frequency of occurrence of each of the categories, as well as 
the relative frequencies. Categorical data will be compared using the χ2 test or Fisher's exact 
test when necessary. RANOVA will be used when more than 2 means of related variables are 
to be compared. Student's t-test should be used when comparing 2 related or independent 
means. In addition, multivariate analysis (multiple linear and logistic regression) will be used 
for the correct modelling of the relationship between variables. The accepted level of 
statistical significance is p<0,05. Data will be analysed using the statistical package SPSS version 
15.0 (SPSS, Inc, Chicago). 
 
REQUEST FOR EVALUATION BY THE CENTRE'S ETHICS COMMITTEE 
 
Immediate application shall be made to the Centre's Research Ethics Committee. 

28 
 
APPLICABILITY OF THE RESULTS 
The applicability of the results will be carried out in the Rehabilitation Services that have a 
Respiratory Physiotherapy unit. 
 
From an economic point of view. 
 
1. The TENS analgesia technique is a low-cost technique and, according to the existing 
literature, it is effective in the process under study. 
2. The existence in the Rehabilitation Services of TENS devices to treat various 
pathologies means that no new investment is required to apply this technique in this 
type of surgical intervention. 
 
From a health point of view. 
 
1. Pain control by TENS analgesia may allow for faster recovery of respiratory 
parameters. 
 
2. Reduced recovery time may result in less use of respiratory physiotherapy units by the 
patient. 
 
3. The lower use of these units results in a higher turnover rate of patients affected by 
this intervention in the Rehabilitation Services. 
 
4. This can lead to a reduction in rehabilitation waiting lists. 
 
From a clinical management point of view. 
 
1. The occupancy rate of Respiratory Physiotherapy Units in Rehabilitation Services may 
decrease significantly. 
 
2. Decreasing the occupancy rate is critical to lowering the cost of the overall expenditure 
of the Rehabilitation Services. 
 
3. The reduction of pain from physical therapies can lead to consequent savings in 
pharmaceutical expenditure. 
 
From a quality of life point of view. 
 
1. Improvements in quality of life factors are closely related to pain. 
 
2. The patient's perception of pain can be significantly reduced by the applicability of 
TENS. 
 
3. Standardisation of optimal quality of life parameters can be achieved in a shorter time. 

29 
 
POTENTIAL PUBLICATION 
The use of TENS in the recovery of patients who have undergone thoracic surgery is a subject 
that has been very little developed to date. We propose that, with a correct methodology, 
such as the one we have proposed in this study, we can achieve two or more works that can be 
published in journals with the highest impact in the speciality. We can also propose 
publications in the field of Rehabilitation and Physiotherapy. 

30 
 
RESEARCH TEAM 
Principal Investigator: Dr. Jorge Freixinet Gilart. Tasks: design of the work, performance of 
surgical interventions and preparation of results, publications and presentations. 
University Hospital of Gran Canaria Dr. Negrín 
 
Associated Researchers: 
 
David Álamo Arce. Tasks: participation in the design of the work, carrying out the 
physiotherapy treatment, data collection and participation in the publications and 
presentations. danieldavid.alamo@ulpgc.es 
 
Daniel López Fernández: participation in the design of the work, physiotherapy treatment, 
data collection and participation in the publications and presentations. 
 
Dr. Pedro Rodríguez Suárez. Tasks: giving speeches, participation in the production of 
publications and presentations. 
 
Dr. Agar Santana León. Tasks: carrying out interventions, data collection, 
participation in the production of publications and presentations. 
 
Dr. Ana Victoria Juárez Sanjuán. Tasks: carrying out interventions, data collection. 
 
Dr. Felipe Rodríguez de Castro. Tasks: assessment and design of respiratory tests, 
participation in publications and presentations. 
 
Dr. Gabriel Juliá Serdá. Tasks: assessment and design of respiratory tests, participation in 
publications and presentations. 
Dr. Esteban Pérez Alonso. Tasks: participation in the design of the work, data collection and 
participation in the production of publications and presentations. 

31 
 
WORK PLAN 
 
1. Patient recruitment and study of patients: January 2015 to December 2017. 
 
2. Collection of data to complement the Clinical History. 
 
Step 3. Introduction to the study. Explanation of the procedure. Signed consent form. 
Step 4. Measurement of parameters: 
1. Measurement of pain, Mc Gill test. 
 
2. Measurement of respiratory parameters. Spirometry. 
 
3. Quality of Life Measure. SF-36. 
 
4. Measured with the Minnesota Multiphasic Personality Inventory. 
 
5. Counting days of treatment. 
 
Step 5. Start of the respiratory physiotherapy programme. It will be carried out in the 
respiratory physiotherapy unit of the University Hospital of Gran Canaria Dr. Negrín. Patients 
will be divided into the two groups described above and will be included in the treatment 
programme. The sequence for the intervention group will be as follows: 
 
1. Explanation of the programme. 
 
2. Placement of external analgesic measures (TENS). The frequency of application would 
be 100 hz as this is the type of application that produces the greatest analgesia. 
10,11,12,13 
 
 
3. Implementation of the treatment regimen, for x days. 
 
4. In the middle of the programme, measurement of all the above 
parameters. Step 6. Continuation of the physiotherapy programme. 
Step 7. Completion of the physiotherapy programme. Measurement of all parameters again, plus 
accounting of treatment days. 
In the control group, the same would be done but no intensity would be given when applying 
TENS. The steps to follow would be the same. 

32 
 
ECONOMIC STUDY 
Within the economic study that will define this work, we will highlight two 
fundamental points: 
 
Portable spirometer brand ..................................................................... 1500 Euros. 
 
Publication of results .............................................................................. 1500 Euros. 
 
Attendance at Conferences and Scientific Conferences ............. 750 Euros. 
 
Publication in scientific journals in the sector ............................. 750 Euros. 
 
TOTAL ..................................................................................................... 3000 Euros. 

33 
 
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34 
 
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35 
 
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2005; 19(2): p. 135-50. 

I 
 
THE FOLLOWING QUESTIONS REFER TO ACTIVITIES OR THINGS THAT YOU MIGHT DO ON A NORMAL DAY. 
ANNEXES 
Annex 1. Quality of Life Questionnaire SF-36 
 
 
 
 
1. 
Overall, you would say that your 
health is: 1 Excellent 
2 Very good 3 
Good 
 
4 Regular 
 
5 Mala 
 
 
2. 
How would you say your health is now compared to a year ago? 1 
Much better now than a year ago 
 
2 Slightly better now than a year ago 3 
About the same as a year ago 4 Slightly 
worse now than a year ago 
5 Much worse now than a year ago 
 
 
 
3. 
Does your current health limit you from making strenuous efforts, such as running, lifting heavy objects, or participating in strenuous 
sports? 1 Yes, it limits me a great deal. 
 
2 Yes, it limits me a little 
bit 3 No, it does not limit 
me at all 
 
4. 
Does your current health limit you to moderate exertion, such as moving a table, vacuuming, bowling, or walking for more than an hour? 1 Yes, it 
limits me a lot. 
 
2 Yes, it limits me a little 
bit 3 No, it does not limit 
me at all 

II 
 
5. 
Does your current health limit your ability to pick up or carry your shopping bag? 
1 Yes, it limits me a lot 2 
Yes, it limits me 
somewhat 
3 No, it does not limit me at all 
 
 
6. 
Does your current health limit your ability to climb several 
flights of stairs? 1 Yes, it limits me a lot. 
 
2 Yes, it limits me a little 
bit 3 No, it does not limit 
me at all 
 
7. 
Does your current health limit your ability to climb a single flight 
of stairs? 1 Yes, it limits me a lot. 
 
2 Yes, it limits me a little 
bit 3 No, it does not limit 
me at all 
 
8. 
Does your current health limit you from bending or kneeling? 
1 Yes, it limits me a lot 2 
Yes, it limits me 
somewhat 
3 No, it does not limit me at all 
 
 
9. 
Does your current health limit you to walk a kilometre or 
more? 1 Yes, it limits me a lot 
 
2 Yes, it limits me a bit 3 
No, it does not limit me at 
all 
 
10. 
Does your current health limit you to walk several blocks (several hundred metres)? 1 
Yes, it limits me a lot 
 
2 Yes, it limits me a bit 3 
No, it does not limit me at 
all 
 
11. 
Does your current health limit you to walk only one block (about 100 
metres)? 1 Yes, it limits me a lot 
 
2 Yes, it limits me a bit 3 
No, it does not limit me at 
all 

III 
 
12. 
Does your current health limit your ability to bathe or dress yourself? 
1 Yes, it limits me a lot 2 
Yes, it limits me 
somewhat 
3 No, it does not limit me at all 

IV 
 
 
 
13. 
During the last 4 weeks, did you have to reduce the time you spent at work or on your daily activities because of your physical health? 1 
Yes 
 
2 No 
 
 
14. 
During the last 4 weeks, did you do less than you would have liked to do, because of your physical 
health? 1 Yes 
 
2 No 
 
 
15. 
During the last 4 weeks, did you have to give up any tasks at work or in your daily activities because of your physical health? 1 Yes 
 
2 No 
 
 
16. 
During the last 4 weeks, did you have difficulty in doing your work or daily activities (e.g., did it cost you more than usual), because of 
 
your physical health? 
1 Yes 
 
2 No 
 
 
17. 
During the last 4 weeks, did you have to reduce the time you spent at work or in your daily activities because of an emotional problem? 
 
(like being sad, depressed, or nervous? 
1 Yes 
 
2 No 
 
 
18. 
During the last 4 weeks, did you do less than you would have liked to do, because of any emotional problems (such as being sad, depressed, or 
 
nervous)? 
1 Yes 
 
2 No 
 
 
19. 
During the last 4 weeks, did you not do your work or daily activities as carefully as usual, because of some problem 
 
emotional (such as being sad, depressed, or nervous)? 
1 Yes 
 
2 No 
 
20. 
20.- During the last 4 weeks, to what extent have your physical health or emotional problems hindered your usual social activities with family, 
friends, neighbours or other people? 
 
 
Not at all 
2 A little 
 
Regular 
4 Quite a lot 
 Very much 
 
 
 
 
21. 
21.- Did you have pain in any part of your body during the last 4 weeks? 
THE FOLLOWING QUESTIONS REFER TO PROBLEMS IN YOUR WORK OR DAILY ACTIVITIES. 

V 
 
THE FOLLOWING QUESTIONS ARE ABOUT HOW YOU HAVE BEEN FEELING AND HOW THINGS HAVE BEEN GOING FOR YOU OVER THE LAST 4 WEEKS. FOR EACH 
QUESTION, PLEASE ANSWER THE QUESTION THAT MOST CLOSELY RESEMBLES HOW YOU HAVE BEEN FEELING. 
1 No, not at all 2 
Yes, very little 3 
Yes, a little bit 
4 Yes, moderate 5 
Yes, very much 
6 Yes, very much so 
 
 
22. 
During the last 4 weeks, to what extent has the pain made it difficult for you to do your usual work (including work outside the home and 
 
housework)? 
1 Nothing 
 
2 Somewhat 
 
3 Regular 
 
4 Quite 
 
5 A lot 
 
 
 
 
23. 
During the last 4 weeks, how much of the time did you feel full of vitality? 
1 Always 
 
2 Almost always 3 
 
Often 4 Sometimes 
 
 Only ever 6 
Never 
24. 
23.- During the last 4 weeks, how much time were you very nervous? 
 
1 Always 
 
2 Almost always 3 
 
Many times 4 
Sometimes 
5 Only ever 6 Never 
 
 
25. 
During the last 4 weeks, for how long did you feel so low in morale that nothing could cheer you up? 
1 Always 
 
2 Almost always 3 
 
Often 4 Sometimes 
 
5 Only some of the time 

VI 
 
6 Never 
 
 
26. 
During the last 4 weeks, how much of the time did you feel calm and 
peaceful? 1 Always 
 
2 Almost always 3 
 
Often 4 Sometimes 
 
5 Only ever 6 Never 
 
 
27. 
During the last 4 weeks, how much of the time did you have a lot of 
energy? 1 Always 
 
2 Almost always 3 
 
Often 4 Sometimes 
 
5 Only ever 6 Never 
 
 
28. 
During the last 4 weeks, how much of the time did you feel discouraged and 
sad? 1 Always 
 
2 Almost always 3 
 
Often 4 Sometimes 
 
5 Only ever 6 Never 
 
 
29. 
During the last 4 weeks, for how long have you felt exhausted? 1 
Always 
 
2 Almost always 3 
 
Often 4 Sometimes 
 
5 Only ever 6 Never 
 
 
30. 
During the last 4 weeks, how long did you feel happy? 1 
Always 
 
2 Almost always 3 
 
Often 4 Sometimes 
 
5 Only some of the time 

VII 
 
PLEASE SAY WHETHER YOU THINK EACH OF THE FOLLOWING STATEMENTS IS TRUE OR FALSE. 
6 Never 
 
 
31. 
During the last 4 weeks, for how long did you feel tired? 1 Always 
 
2 Almost always 3 
 
Often 4 Sometimes 
 
5 Only ever 6 Never 
 
 
32. 
During the last 4 weeks, how often has physical health or emotional problems made it difficult for you to carry out social activities (such as visiting 
 
friends or family)? 
1 Always 
 
2 Almost always 3 
Sometimes 
4 Only ever 5 Never 
 
 
 
 
33. 
I think I get sick more easily than other people. 1 Absolutely true 
2 Fairly certain 3 
Don't know 
4 Quite false 
5 Completely false 
 
 
34. 
I am as healthy as anyone else. 
1 Absolutely true 2 
Quite true 
3 I don't know 
4 Quite false 
5 Completely false 
 
 
35. 
I think my health is going to get worse. 
1 Absolutely true 2 
 
Quite true 
 
3 I don't know 
4 Quite false 
5 Completely false 

VIII 
 
36. 
My health is excellent. 
1 Absolutely true 2 
Quite true 
3 I don't know 
4 Quite false 
5 Completely false 

IX 
 
Annex 2. Gill's Pain Questionnaire