Effectiveness of Hypnoanalgesia for Dermatological Surgery in Children: Randomised Clinical Trial
Phase: NA
Conditions: Anesthesia
Sponsor: Complejo Hospitalario de Toledo

1 
Effectiveness of hypnoanalgesia for dermatological surgery in children: 
Randomised clinical trial 
 
NCT CHT00028 
 
Document Date: March 15, 2019 
 
 
 
 
 
 
PI: Peláez Pérez JM 
1 Anaesthesia and Resuscitation Service, Toledo Hospital Complex. Toledo. Spain 
30 De Barber Avenue, 45004 Toledo - SPAIN 
Email:pelaezju@hotmail.com  
 
 
 
Keywords: Hypnosis, hypnoanalgesia, anxiety, pain, paediatric surgery, dermatology 
 
 

2 
 
State of the art. Justification. 
Since the development of "hypnosedation" by anaesthesiologist Faymonville et al. in 
19771, the combination of hypnosis and conscious sedation techniques with low-dose 
intravenous drugs, or local or locoregional anaesthetic infiltration, has demonstrated 
multiple advantages. These advantages have been observed both in the preoperative 
phase, given the correlation between preoperative anxiety and postoperative pain 2, 3, in 
the perioperative phase, with efficacy observed in minimally invasive procedures and 
awake craniotomy4, 5, and in the postoperative phase, with evidence of a reduction in 
nausea and vomiting, pain and early awakening and discharge6, 7.  
Better knowledge of the technique and its greater use in operating theatres has led to the 
abandonment of the concept of sedation in favour of that of analgesia, which is why the 
term hypnoanalgesia is now used instead of hypnosedation. Patients treated under 
hypnosis show greater comfort and lower levels of anxiety8, 9. In addition, the high 
receptivity and suggestion reached with hypnosis during anaesthesia help to reduce 
analgesic and sedative doses during and after the surgical procedure, which facilitates 
recovery10, 11.  
Doctors and surgeons in the early 19th century already pointed out that children and 
adolescents were particularly "sensitive" to hypnotic techniques, showing good response 
to hypnotherapeutic strategies12. However, most studies of hypnosis and pain have been 
conducted in adults. The mechanisms of action proposed for non-pharmacological 
comprehensive therapies in adults may differ in the paediatric population due to, among 
other reasons, possible developmental effects, requiring specific studies in that 
population10, 13-15.  
Objectives 
The aim of this study is to assess whether the use of hypnoanalgesia in dermatological 
surgery in the paediatric population reduces  
1. the need for sedation and analgesia during the procedure, and  
2. its impact on pain  

3 
a. in the immediate post-operative period and  
b. after 24 hours.  
Secondary objectives are  
1. to assess the degree of acceptance of the procedure and  
2. to evaluate the efficacy of the technique according to the age of the patients and, 
therefore, their suggestibility. 
 
PATIENTS AND METHODS 
Design  
1:1 parallel group unicenter randomized clinical trial.  
 
Randomisation and masking 
Randomisation will be carried out in blocks, depending on the day of the operation (day 
with hypnosedation or day with distraction), without the dermatologists or the 
anaesthetist performing the operation having prior knowledge of either the assigned day 
or the "suggestibility" of the cases, respectively. 
The blinding will be achieved by assigning different investigators to each phase of the 
study, with one designated as responsible for recruitment (MQD), another for intervention 
and control (JMPP), and another for subsequent evaluation in the post-anaesthesia 
recovery unit (URPA) and at 24 hours (responsible nursing staff).  
 
Participants 
Children scheduled for dermatological surgery will be recruited for major outpatient 
surgery (MOS) at the National Paraplegic Centre.  
The following inclusion criteria are established:  
1. age between 5 and 16 
2. any gender / sex 

4 
3. A class I or II of anaesthetic risk according to the American Society of 
Anesthesiologists,  
4. to be in a percentile between P3 and P97 in weight and height,  
5. without known drug allergies, and  
6. having fasted 6 hours for solids and 2 hours for water.  
The following exclusion criteria have been established: 
1. mental retardation  
2. attention deficit,  
3. behavioural disorders,  
4. previous treatment with hypnosis,  
5. history of neurological pathology or psychomotor retardation,  
6. previous pain-related pathology,  
7. obstructive sleep apnoea syndrome (OSAS) 
 
Recruitment will be carried out by the principal investigator from the surgical waiting list 
for a period of 5 months.  
All patients who meet the inclusion criteria will be given informed consent and an 
information sheet, both on the anaesthetic procedure and on hypnosis as an adjuvant 
technique. 
 
Intervention, control and procedures 
Patients will be randomly distributed to one of the following groups: 
 Intervention group: A technique of rapid conversational hypnosis, with focus on 
therapeutic suggestion (guiding the patient into a hypnotic trance), adapted to the 
cognitive development. Induction with hypnotic suggestion focuses and 
accompanies the child's body sensations and allows their active participation. 
After standard sedation, therapeutic suggestion is maintained throughout the 
surgery and in the post-hypnotic period before awakening. 
 Control group: A high-tech distraction technique (Apple®), passive and chosen 
by the child, either an animated video or his or her favourite music. After standard 

5 
intravenous sedation, the child is taken to the operating theatre to watch his or her 
favourite video or music and this is maintained throughout the procedure. 
 
Procedures and concomitant treatments 
In the previous anaesthesia consultation, the therapeutic alliance is established with all 
the children, regardless of the group assigned, giving them the opportunity to choose their 
favourite experience of therapeutic suggestion, according to their age and level of 
cognitive maturity.  
Patients and tutors are given a behavioural therapeutic session to reduce the anxiety and 
fear associated with the procedure and to eliminate any negative connotations associated 
with medical hypnosis.  
Prior to surgery, the pre-surgical checklist will be completed. The entire surgical team 
has received training in conversational hypnosis and attention-distracting techniques from 
the principal investigator, a paediatric anaesthetist, with academic qualifications and 
experience in clinical hypnosis.  
In the anteroom of the operating room, all children will be offered to play, such as with 
fruit-smelling markers to colour the inside of the anaesthetic mask (Stabylo®).  
During surgery, standard sedation will be performed either intravenously or inhalationally 
as an option. In the endovenous induction, an initial dose of propofol of 2.5 mg/Kg will 
be injected, registering the additional amount needed. If the additional doses are not 
sufficient, a short duration opioid, alfentanil, will be administered at a dose of 10-15 
micrograms/kg. For inhalation induction, a mixture of nitrous oxide and oxygen (60/40) 
will be administered at tidal volume with an external Mapelson C circuit (Maquet Flow-
i C20®). Finally, the surgeon, in agreement with the anaesthetist, used local anaesthesia 
with 2% subcutaneous lidocaine. 
Waking up will be carried out in the operating theatre with subsequent transfer to the 
Post-Anaesthesia Care Unit (PACU), where, in addition to control of constants, pain will 
be assessed using adapted scales (see variables and measurements below), and analgesics 
will be administered where necessary (if VAS>4 paracetamol will be used, 15 mg/kg, and 
if pain persisted, magnesium metamizole at a dose of 20 mg/kg).  
 

6 
Evaluation and Outcome Measures 
The following outcome variables are established: 
 Main variable: Total dose of propofol and additional need for opioids during the 
operation, measured in mg/kg of weight as recorded intra-operatively. 
 Impact on pain and analgesic needs, both in the immediate post-operative period and 
24 hours after the operation, measured by pain scales adapted to age and cognitive 
maturation (Visual Analogical Scale (VAS) from 10 years and Face Drawing Scale 
or FPS-r from 5 to 9 years), need for paracetamol, ibuprofen or other analgesics. The 
scales are given to the children by the nurse in charge at the PACU, who will be also 
responsible for the 24-hour post-surgery follow-up, and did not know the group to 
which each patient belonged. The analgesic need will be collected from the medical 
logs. 
 Degree of satisfaction with the procedure, using a scale of 1 to 10, administered at the 
time of discharge from hospital to the children or their guardians. 
 
Statistical analysis 
For the descriptive analysis, central tendency and dispersion measures will be used 
(median and 25th to 75th percentiles, P25-75) for quantitative variables, and absolute and 
relative frequencies for qualitative ones. The comparison of the outcome measures 
between the intervention group and the control group will be carried out by means of non-
parametric tests: chi-square and Fisher's exact test for qualitative outcome measures, and 
Mann-Whitney's U for the quantitative ones.  
An age-based subgroup analysis will be conducted (under 7 years and over). 
The significance level will be set at a value of p<0.05 and the analysis will be carried out 
with Excel®. 
A sample of 30 patients will be calculated to detect a 40 mg dose difference between the 
two groups, with a risk α of 0.05 and a risk β of 0.20 in a bilateral contrast and assuming 
a common standard deviation of 33.3 and a loss to follow-up rate of 10%. 
 
 

7 
Ethical aspects 
The study will be conducted in accordance with the WHO code of ethics (Declaration of 
Helsinki) on human experimentation and will seek approval by the Clinical Research 
Ethics Committee of the Toledo Hospital Complex.  
FINANCING 
This study has no funding. 
 
REFERENCES 
1. 
Faymonville ME, Mambourg PH, Joris J, Vrijens B, Fissette J, Albert A, et al. 
Psychological approaches during conscious sedation. Hypnosis versus stress reducing strategies: 
a prospective randomized study. Pain. 1997;73:361-7. 
https://doi.org/10.1016/s0304-3959(97)00122-x 
2. 
Duparc-Alegria N, Tiberghien K, Abdoul H, Dahmani S, Alberti C, Thiollier AF. 
Assessment of a short hypnosis in a paediatric operating room in reducing postoperative pain and 
anxiety: A randomised study. J Clin Nurs. 2018;27:86-91. 
https://doi.org/10.1111/jocn.13848 
3. 
Fortier MA, Weinberg M, Vitulano LA, Chorney JM, Martin SR, Kain ZN. Effects of 
therapeutic suggestion in children undergoing general anesthesia: a randomized controlled trial. 
Paediatr Anaesth. 2010;20:90-9. 
https://doi.org/10.1111/j.1460-9592.2009.03225.x 
4. 
Miller K, Tan X, Hobson AD, Khan A, Ziviani J, O'Brien E, et al. A Prospective 
Randomized Controlled Trial of Nonpharmacological Pain Management During Intravenous 
Cannulation in a Pediatric Emergency Department. Pediatr Emerg Care. 2016;32:444-51. 
https://doi.org/10.1097/PEC.0000000000000778 
5. 
Lohkamp LN, Mottolese C, Szathmari A, Huguet L, Beuriat PA, Christofori I, et al. 
Awake brain surgery in children-review of the literature and state-of-the-art. Childs Nerv Syst. 
2019;35:2071-7. 
https://doi.org/10.1007/s00381-019-04279-w 
6. 
Browne PD, den Hollander B, Speksnijder EM, van Wering HM, Tjon ATW, George EK, 
et al. Gut-directed hypnotherapy versus standard medical treatment for nausea in children with 
functional nausea or functional dyspepsia: protocol of a multicentre randomised trial. BMJ Open. 
2019;9:e024903. 
https://doi.org/10.1136/bmjopen-2018-024903 

8 
7. 
Calipel S, Lucas-Polomeni MM, Wodey E, Ecoffey C. Premedication in children: 
hypnosis versus midazolam. Paediatr Anaesth. 2005;15:275-81. 
https://doi.org/10.1111/j.1460-9592.2004.01514.x 
8. 
Lynn SJ, Kirsch I, Barabasz A, Cardena E, Patterson D. Hypnosis as an empirically 
supported clinical intervention: the state of the evidence and a look to the future. Int J Clin Exp 
Hypn. 2000;48:239-59. 
https://doi.org/10.1080/00207140008410050 
9. 
Pelaez-Perez JM. Entrée dans l'IRM. Le tunnel magique et filin. Revue Hypnose & 
Thérapies brèves. 2019:50-2. 
 
10. 
Kuttner L. Pediatric hypnosis: pre-, peri-, and post-anesthesia. Paediatr Anaesth. 
2012;22:573-7. 
https://doi.org/10.1111/j.1460-9592.2012.03860.x 
11. 
Mackey EF. An Extension Study Using Hypnotic Suggestion as an Adjunct to 
Intravenous Sedation. Am J Clin Hypn. 2018;60:378-85. 
https://doi.org/10.1080/00029157.2017.1416279 
12. 
Oleness K, Kohen DP. Hypnosis and Hypnotherapy with children. 4th ed. New York: 
Guillford; 1996. 
13. 
Richardson J, Smith JE, McCall G, Pilkington K. Hypnosis for procedure-related pain 
and distress in pediatric cancer patients: a systematic review of effectiveness and methodology 
related to hypnosis interventions. J Pain Symptom Manage. 2006;31:70-84. 
https://doi.org/10.1016/j.jpainsymman.2005.06.010 
14. 
Wood C, Bioy A. Hypnosis and pain in children. J Pain Symptom Manage. 2008;35:437-
46. 
https://doi.org/10.1016/j.jpainsymman.2007.05.009 
15. 
Faymonville ME, Laureys S, Degueldre C, DelFiore G, Luxen A, Franck G, et al. Neural 
mechanisms of antinociceptive effects of hypnosis. Anesthesiology. 2000;92:1257-67. 
https://doi.org/10.1097/00000542-200005000-00013 
16. 
Tosti G. Definitions et rouages de l’hypnosis. In: Eyrolles G, editor. Le grand livre de 
l’hypnose. Paris2016. p. 38-40. 
17. 
Vanhaudenhuyse A, Boly M, Balteau E, Schnakers C, Moonen G, Luxen A, et al. Pain 
and non-pain processing during hypnosis: a thulium-YAG event-related fMRI study. 
Neuroimage. 2009;47:1047-54. 
https://doi.org/10.1016/j.neuroimage.2009.05.031 
18. 
Raja SN, Carr DB, Cohen M, Finnerup NB, Flor H, Gibson S, et al. The revised 
International Association for the Study of Pain definition of pain: concepts, challenges, and 
compromises. Pain. 2020. 
https://doi.org/10.1097/j.pain.0000000000001939 

9 
19. 
Montgomery GH, DuHamel KN, Redd WH. A meta-analysis of hypnotically induced 
analgesia: how effective is hypnosis? Int J Clin Exp Hypn. 2000;48:138-53. 
https://doi.org/10.1080/00207140008410045 
20. 
Montgomery GH, Schnur JB, Kravits K. Hypnosis for cancer care: over 200 years young. 
CA Cancer J Clin. 2013;63:31-44. 
https://doi.org/10.3322/caac.21165 
21. 
Manyande A, Cyna AM, Yip P, Chooi C, Middleton P. Non-pharmacological 
interventions for assisting the induction of anaesthesia in children. Cochrane Database Syst Rev. 
2015:Cd006447. 
https://doi.org/10.1002/14651858.CD006447.pub3 
22. 
Friedrichsdorf SJ. Multimodal pediatric pain management (part 2). Pain Manag. 
2017;7:161-6. 
https://doi.org/10.2217/pmt-2016-0051 
23. 
Thompson T, Terhune DB, Oram C, Sharangparni J, Rouf R, Solmi M, et al. The 
effectiveness of hypnosis for pain relief: A systematic review and meta-analysis of 85 controlled 
experimental trials. Neurosci Biobehav Rev. 2019;99:298-310. 
https://doi.org/10.1016/j.neubiorev.2019.02.013