The Use of a Second-Generation Laryngeal Mask Airway Versus Endotracheal Tube in Obese Patients
Phase: NA
Conditions: Obese, Endotracheal Tube, Laryngeal Mask Airway
Sponsor: University of Texas Southwestern Medical Center

STUDY PROTOCOL AND STATISTICAL ANALYSIS PLAN 
 
 
Official title: The Use of a Second-Generation Laryngeal Mask Airway 
versus Endotracheal Tube  
in Obese Patients 
 
NCT number: NCT03748342 
IRB approved date: 07-28-21 
 

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The Use of a Second-Generation Laryngeal Mask Airway versus Endotracheal Tube  
in Obese Patients 
 
Principal Investigator:  Tiffany Sun Moon, MD 
 
 
Sponsor/Funding Source:  UT Southwestern of Department of Anesthesiology and Pain Management 
 
Version 3.1 06/21/2021 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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The University of Texas Southwestern Medical Center 
Institutional Review Board 
 
PROJECT SUMMARY 
 
 
Introduction and Purpose: 
The laryngeal mask airway (LMA) was invented in the 1980s and has been used in millions of patients 
worldwide.  Since that time, the original prototype has been modified in several ways in order to improve 
the design of the LMA.  “Second-generation” LMAs are those with a gastric channel, through which an 
orogastric tube can be inserted to decompress the stomach.  
 
The LMA is associated with a decreased incidence of sore throat as well as a smoother emergence 
from general anesthesia compared to endotracheal tubes [1].  In randomized studies comparing second 
generation LMAs with endotracheal tubes, patients have been shown to have less pain and 
postoperative nausea and vomiting with LMAs [2]. 
 
In this prospective study, we plan to evaluate the use of a second-generation laryngeal mask airway 
(LMA) versus an endotracheal tube (ETT) in obese patients undergoing surgery.  The second-
generation LMAs offer additional benefits over traditional LMAs since they include a gastric channel 
through which an orogastric tube can be inserted to decompress the stomach.  Modifications in the cuff 
have been shown to decrease the incidence of sore throat and achieve higher seal pressures [3, 4].  
Some even include an integrated cuff pressure indicator, which allows the practitioner to assess inflation 
cuff pressures, therefore minimizing the incidence of over-inflation, which can cause mucosal ischemia 
and increase the incidence of sore throat [5]. 
 
 
Specific Aim 1: 
To compare the use of a second-generation LMA versus endotracheal intubation with respect to the 
incidence of hypoxia in the immediate postoperative period. 
 
Primary Hypothesis: Patients managed with the second-generation LMA will have a 50% decreased 
incidence of hypoxia compared with patients managed with an endotracheal tube. 
 
Specific Aim 2: 
To determine the alterations in hemodynamics with insertion and removal of the LMA versus an 
endotracheal tube.   
 
Secondary Hypothesis:  The LMA will cause less hemodynamic alterations for insertion and removal 
compared to an endotracheal tube. 
 
 
 
 
 

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Background: 
The laryngeal mask airway (LMA) was invented in 1983 and has been in clinical use since 1988 with 
millions of uses worldwide [6].  It has a very good record of successful insertion and the learning curve 
for LMA insertion is not as steep as that for direct laryngoscopy and intubation [5].  In a series of almost 
12,000 patients, LMA placement was successful in 99.8% of patients [7]. The LMA has a lower risk of 
airway complications since its placement does not necessitate laryngoscopy and its final position sits 
superior to the vocal cords and trachea, therefore causing less airway trauma [5].  The LMA was 
designed for either spontaneous or controlled positive pressure ventilation (PPV).  In his first clinical 
series using the LMA, Dr. Brain described 16 cases of PPV in patients undergoing gynecologic surgery 
[6]. Use of the LMA in abdominal surgery, including laparoscopic gynecological surgery, has been 
documented in previous studies [8].  Newer, so called ‘second-generation’ LMAs have an additional 
gastric drainage tube, which allows passage of an orogastric tube to decompress the stomach.  This 
separation of the alimentary and respiratory tracts is a significant advantage of second-generation 
LMAs.  Additionally, higher airway pressures are afforded by these devices, which allow the provider to 
provide positive pressure ventilation without gastric insufflation. Therefore, these newer devices offer 
increased protection against aspiration when compared to first-generation LMAs.  When second-
generation LMAs are properly positioned, the risk of pulmonary aspiration is very low [9-11]. 
 
Insertion of an LMA is significantly less stimulating than insertion of an endotracheal tube (ETT), as 
direct laryngoscopy is not required for LMA insertion [12, 13].  Prior studies have shown that compared 
with ETT insertion, LMA insertion resulted in less hemodynamic and hormonal activation [14, 15].  The 
stress of surgery itself promotes platelet aggregation and thrombus formation, thus predisposing 
patients to ischemic events in the perioperative period [16]. Catecholamines increase heart rate and 
blood pressure and therefore increase myocardial oxygen consumption. By decreasing the stress 
response associated with airway manipulation, the LMA may be advantageous compared to the ETT, 
especially for patients with comorbidities (e.g., obesity) that may predispose them to cardiovascular 
complications. 
 
LMA use results in less postoperative cough, laryngospasm, sore throat, hoarseness, and postoperative 
nausea and vomiting (PONV) compared to ETTs [2, 5, 8, 10, 17]. Additionally, use of a LMA compared 
to an ETT results in less postoperative hypoxemia and sore throat in the PACU [14].  Excessive intracuff 
pressures can lead to pharyngolaryngeal complications including sore throat, dysphagia, and dysphonia 
[18, 19].  The modifications to the cuff of second-generation LMAs can decrease the incidence of 
postoperative pharyngolaryngeal symptoms [20].   
  
Patients who are managed with LMAs require less muscle relaxants than patients managed with ETTs.  
Upper airway muscles are very sensitive to the effects of residual neuromuscular blockade, increasing 
the risk of microaspiration, hypoxia, and pharyngeal dysfunction postoperatively [21, 22].  Being able to 
decrease the amount of neuromuscular blockade necessary could therefore result in less postoperative 
respiratory adverse events, especially in patients intolerant of residual neuromuscular blockade such 
as those who are obese.  Previous studies have used the LMA for successful ventilation of obese 
patients [23-25].  
 
In a recent Cochrane review of LMAs vs ETTs in obese patients, the authors concluded that there was 
a significant improvement in oxygenation during and after surgery, including better pulmonary 
performance of the second-generation LMA.  They also reported less postoperative coughing, 
suggesting a better recovery for patients [26]. Another prospective study evaluating the use of LMA vs. 
ETT in moderately obese patients undergoing peripheral surgeries concluded that the LMA group had 
better early postoperative lung function and pulse oximetry saturation compared with the ETT group 
[27].  
 
Compared to airway management with an ETT, the use of LMAs resulted in a shorter PACU stay and 
a faster discharge home [14].  In a hospital such as Parkland with a busy surgical service and limited 
resources, the associated cost savings could be significant [28].   
 

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There has been inconclusive evidence of whether obese patients have higher gastric volumes 
compared to lean patients but recent articles report that there does not seem to be a link between 
obesity and delayed gastric emptying [29-32]. Gastric ultrasound is a noninvasive tool to examine 
stomach contents at the bedside and is feasible in lean and severely obese patients [33, 34]. The antrum 
is highly amenable to ultrasound imaging and accurately reflects the content of the entire stomach [35]. 
A volume of < 1.5mL/kg suggests low gastric volumes and a low risk of aspiration [36]. 
 
 
Concise Summary of Project: 
This prospective, randomized, comparative study is intended to enroll a total of 150 obese patients with 
a BMI >30 kg/m2  undergoing surgery at Parkland Hospital.  There will also be a second site (MD 
Anderson) that will enroll an additional 150 obese patients. The efficacy and performance of the second-
generation LMA will be compared to endotracheal intubation.  A standardized anesthetic protocol that 
is usual and customary for the type of operation the patient is having will be provided to the anesthesia 
teams of enrolled subjects.  The remainder of the anesthetic care of the subject will not deviate from 
the standard of care. 
 
 
Study Procedures: 
Screening and Informed Consent 
A member of the research team will use a screening form to look for surgical patients that meet all the 
inclusion and exclusion criteria. He/she will approach potential subjects in the preoperative area and 
the study will be explained in detail in a private room.  Patients will be informed that they will receive no 
compensation for participating in the study and there will be no adverse consequences if they choose 
not to participate. If the subjects agree to participate, informed written consent will be obtained prior to 
any study procedures and this document will be sent to pmhresearchparticipants@phhs.org, for 
inclusion in the patient’s medical record, per Parkland regulations. The study duration will be from the 
beginning of anesthesia care to 2 hours after the patient’s surgery ends.  
 
Anesthetic Protocol 
The anesthesia team that will be caring for the subject during surgery will be given the protocol for the 
study, which standardizes the general anesthetic technique.   
 
Subject Group Assignment: 
A randomization schedule will be created by a member of the research team that is not involved in 
clinical care (i.e., statistician).  Subjects will be randomized to receive either a standard endotracheal 
tube or a second-generation LMA.  The ETT size will be selected based on gender- 7.0 for women and 
8.0 for men.  LMA sizing will be according to manufacturer guidelines.   
 
In the preoperative holding area, a gastric ultrasound will be performed to rule out the presence of 
significant gastric contents.  This will be done with a curved array low-frequency transducer on the 
current ultrasound machine that is already available in the preop area.  No visible contents in the gastric 
antrum in either the supine or right lateral decubitus (Grade 0) provides unequivocal diagnosis of an 
empty stomach.  A threshold of 1.5 mL/kg will be the upper limit of acceptable gastric volume.  Any 
patients who has more than this volume will not undergo any further study procedures.   
 
Once the patient is in the operating room, they will be positioned on the operating room table and 
standard ASA monitors will be applied.  All patients will undergo a standard anesthetic induction.  
Patients who are randomized to endotracheal intubation will also have a neuromuscular blocking agent 
(i.e., rocuronium) administered to facilitate intubation.  
 
Preparation of the endotracheal tube will consist of ensuring that the cuff holds air as well as inserting 
a stylet into the endotracheal tube.  Preparation of the LMA will consist of ensuring that the cuff holds 
air, and then withdrawing all the air in preparation for insertion, per manufacturer guidelines.  A water-
soluble lubricant will be applied to the dorsal surface of the LMA to assist with insertion, which is 

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standard practice. 
 
Following induction of anesthesia, if a patient is randomized to the ETT group, the anesthesia provider 
will perform a direct laryngoscopy and insert an endotracheal tube.  The time that the face mask is taken 
off the patient’s face will be recorded as the ‘start time’ for laryngoscopy, and the ‘end time’ will be when 
the positive ETCO2 tracing appears.  For patients randomized to the LMA group, the anesthesia provider 
will be asked to insert the LMA in the patient’s posterior oropharynx until resistance is encountered.  It 
will then be secured with a piece of tape, per manufacturer guidelines.  Then the cuff will then be inflated.  
The time that the face mask is taken off the patient’s face will be recorded as the ‘start time’ for LMA 
placement, and the ‘end time’ will be when the positive ETCO2 tracing appears.  A fiberoptic 
bronchoscope will be inserted through the lumen of the LMA to ensure that its placement is correct (i.e., 
just proximal to the glottic inlet).  Correct placement of the LMA will also be tested with the gel 
displacement test [37, 38]. This test will be performed by placing 5 mL of water-soluble gel over the 
male drainage tube while occluding the female draining lumen and looking for its ejection during manual 
ventilation.  A ‘negative’ test (gel does not move) indicates that there is no air leak from the airway port 
to the gastric port, and the LMA is correctly positioned.  A ‘positive’ test (gel is displaced during 
ventilation) indicates that there is an air leak into the gastric port, and the LMA needs to be repositioned. 
Following confirmation of adequate ventilation, an orogastric tube will be inserted through the gastric 
channel of the LMA.  Correct gastric tube placement will be confirmed by aspiration of gastric contents 
(amount will be recorded) or by auscultation during insufflation of 30 mL of air into the gastric tube. 
 
Successful LMA and ETT placement will be defined as chest rise during ventilation, a square 
capnography waveform, bilateral breath sounds, and no air leakage.  A maximum of three tries will be 
allowed for subjects in the LMA group.  If the LMA is not properly placed after 3 attempts, the anesthesia 
provider will be asked to intubate the patient with an endotracheal tube and a ‘LMA failure’ will be noted.  
Details regarding ETT placement including Cormack-Lehane grade, number of attempts, number of 
operations, and use of any adjunct airway devices will be recorded. 
 
Following confirmation of LMA or ETT placement, the patient will be ventilated using volume control 
ventilation with an inspiratory:expiratory ratio of 1:2, tidal volume of 6-8 mL/kg of ideal body weight 
(IBW) and a rate of 8-12, titrated to keep the ETCO2 between 35-45 mmHg, and fresh gas flow rate of 
2 L/min.  Patients who are breathing spontaneously will be managed with pressure support ventilation 
(PSVPro).  Immediately after confirmation of LMA or ETT placement, the patient will be placed on 1-2% 
sevoflurane in 50% oxygen. 
 
Additional information collected will include: 
• 
Aspiration at induction 
• 
Amount and description of gastric fluid aspiration through orogastric tube suction (either through 
LMA or ETT) 
• 
Evidence of gastric content after airway device removal 
• 
Intraoperative medications 
• 
Medications given in PACU 
• 
Aldrete scores in PACU 
• 
Hypoxic episodes in PACU 
 
Vital signs including SpO2, heart rate (HR), blood pressure (BP) will be recorded at the following times: 
- 
Baseline in operating room prior to induction 
- 
At induction (Ti) 
- 
Immediately after placement of LMA/ETT  
- 
Three minutes following placement of LMA/ETT 
- 
Five minutes following placement of LMA/ETT 
- 
Ten minutes following placement of LMA/ETT 
- 
Just prior to removal of LMA/ETT 
- 
Immediately after removal of LMA/ETT 

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- 
Three minutes following removal of LMA/ETT 
- 
Five minutes following removal of LMA/ETT 
- 
Ten minutes following removal of LMA/ETT 
 
A blinded research assistant will perform all postoperative assessments. All patients will go to the post 
anesthesia care unit (PACU) after surgery, unless an intraoperative complication necessitates that the 
patient go to the intensive care unit (ICU), at which time they would no longer be a part of the study.  As 
patient-reported outcomes have become increasingly important for hospitals, treatments that have the 
potential to increase patient satisfaction are being studied closely. The postoperative quality recovery 
scale (PQRS) is a tool that assesses recovery over time and compares them to baseline values.  Some 
of the advantages of the PQRS are that it is validated, takes less than 5 minutes to administer, has a 
low patient refusal rate, and is acceptable to patients across a wide range of ages. The PQRS will be 
administered at baseline in the preoperative area, and after PACU arrival at 15 minutes and again at 
45 minutes and 80 minutes (Appendix 1). The time when the patient arrives to the PACU, is ready for 
discharge from the PACU (modified Aldrete score ≥9) and actual discharge from the PACU will be 
recorded. 
 
After the first ten patients have been enrolled, the PI and the research team will review the cases to 
make any adjustments to the protocol to better facilitate data collection for the remaining study 
participants.  
 
Data Sources 
Protected health information including name, medical record number, and date of birth will be recorded 
and stored securely in a password-protected, secured Excel database. De-identified data will be entered 
in RedCap data management system.  
 
 
Parameters: 
1. Protected health information (PHI):  name, medical record number, date of birth, phone number 
2. Demographic information (age, weight, height, BMI, gender), medical and surgical history, ASA) 
3. Intraoperative parameters  
• 
Baseline vital signs upon arrival to operating room 
• 
Time of induction  
• 
Intraoperative vitals (systolic, diastolic, and mean blood pressures, heart rate) 
• 
ECG rhythm 
• 
Laryngoscopy details (Cormack Lehane view, blade used) 
4.  Adverse event monitoring 
• 
LMA unable to be inserted after 3 attempts 
• 
Patient unable to be intubated (e.g., difficult airway) 
• 
Prolonged hypoxia (> 1 min at <92%) from anesthesia start to anesthesia stop  
• 
Respiratory adverse event including bronchospasm, laryngospasm aspiration, reintubation 
• 
Prolonged PACU stay (> 2 hours) 
• 
Unplanned hospital admission 
 
 
Criteria for Inclusion of Subjects: 
• 
18-80 years old 
• 
Obese BMI > 30 kg/m2 
• 
Scheduled for a non-emergent surgery that requires general anesthesia (e.g., orthopedic, 
breast, urological, colorectal, ENT, vascular, general surgery) 
• 
Willing and able to consent in English or Spanish 
• 
No current history of advanced pulmonary or cardiac disease 
 
Criteria for Exclusion of Subjects: 

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• 
Age less than 18 or older than 80 
• 
BMI >50 or < 30 kg/m2 
• 
Patient does not speak English or Spanish 
• 
Expected surgical duration longer than 4 hours 
• 
Planned postoperative ICU admission 
• 
Patient refusal 
• 
Monitored anesthesia care (MAC) or regional anesthesia without general anesthesia 
• 
Pregnant or nursing women 
• 
“Stat” (emergent) cases 
• 
Known or suspected difficult airway 
• 
Appearance of residual gastric volume >1.5 mL/kg on preoperative gastric ultrasound 
• 
Full stomach/significant aspiration risk (gastroparesis, emergency surgery, untreated moderate 
to severe gastroesophageal reflux disease, hiatal hernia) 
• 
No history of gastric surgery   
• 
Surgery in position other than supine (e.g., Trendelenburg) 
• 
Laparoscopic surgery 
 
Sources of Research Material: 
• 
Identifying patient information including name, medical record number, and birth date 
• 
Medical history  
• 
Surgical history 
• 
Weight and height 
• 
Laboratory studies 
• 
Vital signs 
• 
Intraoperative anesthetic record 
 
Recruitment Methods and Consenting Process: 
A member of the research team will approach subjects who meet all inclusion and exclusion criteria on 
the day of surgery in a private room.  All study procedures will be explained to the patient in layman’s 
terms.  If the subject agrees to participate, he or she will sign the consent form and HIPAA Authorization 
Form prior to any study procedures.  
 
Potential Risks: 
There is some risk to subjects by participating in this study.  The anesthetic management of subjects 
will not differ from the standard care.  Patients will be randomized to be intubated with an endotracheal 
tube or have an LMA inserted as part of the airway management for their surgery.  There is a very small 
risk of aspiration anytime a patient undergoes general anesthesia.  A LMA is not considered a ‘secured 
airway’ because there is no cuff in the patient’s trachea.  Therefore, there is a risk of aspiration with a 
LMA.  However, the overall incidence of aspiration with general anesthesia is very low (approximately 
1 in 5000 general anesthetics) and no studies have been powered to look directly at aspiration. From 
existing studies, the LMA groups did not have a higher incidence of aspiration compared with the ETT 
groups [5, 39, 40]. One caveat is that patients at risk for aspiration have been excluded from these 
studies, which will also be done for this study.  Currently there is no evidence to suggest that the use of 
a LMA (especially a second generation LMA) in appropriately selected patients increases the risk of 
aspiration compared with ETT [27]. 
 
Study Procedure/Intervention 
The table below will be included in the consent form and lists the risks of ETT vs LMA placement.   
 
Risks of Endotracheal Tube (ETT) 
 
Frequent  
30% of subjects 
Occasional  
15% of subjects 
Rare  
Less than 1% of 
subjects 

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Serious 
 
Incorrect placement 
Difficult intubation 
Tracheal perforation 
Aspiration 
Tracheal stenosis 
Less Serious 
Sympathetic surge 
(increased heart rate 
and blood pressure) 
Trauma to vocal 
cords, trachea, soft 
tissues 
Bronchospasm (lower 
airway obstruction) 
Laryngospasm (upper 
airway obstruction) 
Dental damage 
 
Minor 
Sore throat  
Cough 
Minor bleeding 
Laryngeal edema 
(swelling of the throat) 
Lip damage 
Dysphonia 
(hoarseness) 
Dysphagia (difficulty 
swallowing) 
 
 
 
 
Risks of Laryngeal Mask Airway 
 
Frequent  
30% of subjects 
Occasional  
15% of subjects 
Rare  
Less than 1% of 
subjects 
Serious 
 
Difficult placement 
Aspiration  
Less Serious 
Sympathetic surge 
(increased heart rate 
and blood pressure) 
Bronchospasm (lower 
airway obstruction) 
Laryngospasm (upper 
airway obstruction) 
Local tissue injury 
Dental damage 
Minor 
Sore throat 
Cough 
Minor bleeding 
Laryngeal edema 
(swelling of the throat) 
Lip damage 
Dysphonia 
(hoarseness) 
Dysphagia (difficulty 
swallowing) 
 
 
Psychological Stress 
There is minimal risk for psychological stress to the patient as a result of participation in this study.  
Subjects may refuse to answer any of the questions, or take a break or stop participation in the study 
at any time. 
 
Subject Safety and Data Monitoring 
Study oversight will include a Data Safety and Monitoring Board (DSMB).  The DSMB will be chaired 
by a faculty member that is not the PI and will include specialists from different specialties including 
anesthesiology, critical care medicine, and surgery.  The DSMB will meet quarterly as needed to review 
all patient enrollments.  If necessary the DSMB will meet more often to review specific study subjects, 
unanticipated events, protocol violations, and adverse events.  All study subjects will be reviewed by 

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the DSMB for any study-related adverse outcomes.  A written record of all meetings will be kept.  The 
IRB will be notified in writing of any adverse study-related outcomes. 
 
Procedures to Maintain Confidentiality: 
A non-identifiable code will be assigned to the data collection sheet so that there is not a direct link to 
specific names.  Patient IDs will be standardized in chronological order as patient 1, patient 2, etc. A 
key to the coding system will be maintained in a locked storage cabinet with limited access until all the 
data is collected and analyzed. Access to study data will be restricted to authorized study personnel 
only. Following the completion of the analysis and the project, the key to the coding system or subject 
identifiers themselves will be destroyed by shredding the documents so that there is no direct or indirect 
link to subject identifiers and information. 
 
All data from the study will be kept on encrypted computers belonging to the University, which are stored 
in secured areas. All electronic study data will be password protected and passwords will be changed 
on a regular basis. Patient data will be analyzed without patient identifiers by assigning study ID subject 
numbers that are de-linked from patient identifiers.  Signed consent forms, HIPAA forms, and study 
questionnaires will remain in a locked cabinet in the PI’s office. 
 
 
Potential Benefits: 
Previous studies have shown that appropriately selected patients who undergo surgery with a LMA 
(compared to an ETT) have less pulmonary physiological derangement in the postoperative period, as 
well as less pain and postoperative nausea and vomiting.  Patients who are randomized to the LMA 
group may benefit from this.  However, the study is not intended to directly benefit patients in either 
group (LMA vs. ETT).   
 
Data Sharing 
Data will be shared via RedCap; UT Southwestern PI will have access to the MD Anderson deidentified 
RedCap database and download an Excel data file. UT Southwestern will receive the deidentified data.  
 
UT Southwestern team who have access to MD Anderson Center RedCap will download the 
deidentified data. RedCap (https://redcap.mdanderson.org) is hosted on a secure server by MD 
Anderson Cancer Center’s Department of Oncology Care & Research Information Systems. RedCap 
has undergone an annual Governance Risk & Compliance Assessment (since May 2014) by MD 
Anderson’s Information Security Office and found to be compliant with HIPAA, Texas Administrative 
Coes 202-203, University of Texas Policy 165, federal regulations outlined in 21CFR Part 11, and 
UTMDACC Institutional Policy #ADM0335.  
 
Those having access to the data include the study’s PI and research team personnel of both study sites. 
Users are authenticated against MDACC’s Active Directory system. External collaborators are given 
access to the database once approved by the PI, with their access expiring in 6 months, but renewable 
in 6 month increments at the request of the PI. The application is accessed through Secure Socket 
Layer (SSL). 
 
 
Statistics: 
The study is powered to detect a change in the incidence of sore throat post-operatively between 
subjects in the ETT and LMA groups.  Assuming a 20% rate of incidence of sore throat in the ETT 
group, the study is powered to detect a 50% reduction in the incidence rate to 10% (risk ratio = 1/2) in 
the LMA group.  With these assumptions, the study will need a total of 116 patients to have 80% 
power (two-sided chi-square test with type I error rate = 0.05).  To account for patient dropout, a total 
of 150 patients will be enrolled.  The continuous data will be summarized as mean and standard 
deviation or median and inter-quartile range, as appropriate while categorical data will be summarized 
as frequency and percentages.  The incidence rates of sore throat in the two groups will be compared 

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using a chi-square test or Fisher’s exact test.  Statistical significance is set at p=0.05.  All analyses will 
be done using SAS 9.3 (SAS Inc., Cary, NC).

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Appendix 1: Postoperative Quality Recovery Scale evaluation at baseline, T15, T45, T80 
 
Demographic and Preoperative Dataa 
Age  
yrs 
Gender 
Male or Female 
ASA Status 
1     2     3     4 
Weight 
kg 
Height 
in 
BMI 
kg/m2 
Education 
Highest level finished: 
Alcohol consumption 
units/wk 
Smoking status 
Never, used to but quit, current smoker 
Employment 
Unemployed  
Employed and plan to return 
Employed but plan not to return 
Occupation:  
Approximate hrs/wk: 
Inpatient 
Yes or No 
Surgical procedure 
 
 
Physiological Factorsa,d 
P1 Blood Pressure 
Please record the patient’s blood 
pressure 
 
 
3= SBP 90-140; 2= SBP 70-89 or 141-180;  
1= SBP <70 or >180 
P2 Heart Rate 
Please record the patient’s heart rate 
 
 
3= 45-100; 2= 35-44 or 101-139; 1= <35 or >140 
P3 Temperature 
Please record the patient’s 
temperature 
Method 1. Sublingual 2. Tympanic 3. Esophageal 
 
3= 36-37.6; 2= 35-35.9 or 37.7-38.9; 1= <35 or >39 
P4 Respiration 
Please record the patient’s respiratory 
rate 
                        
 /breaths per minute 
P5 Oxygen use to maintain SpO2 
Please record oxygen requirement 
3= Oxygen administered by protocol or not 
required 
2= Any SpO2 <95% requiring oxygen as an 
intervention 
1= Any SpO2 <90% requiring oxygen as an 
intervention 
P6 Airway 
Please record the number 
corresponding to the assessment 
3= Self-maintenance of airway 
2= Maintenance of airway with support 
(describe) 
1= Device in situ 
P7 Agitation 
Please record the number 
corresponding to the assessment 
3= Shows no signs of agitation 
2= Patient shows occasional agitation 
1= Patient shows severe agitation 
P8 Alertness 
Please record the number 
corresponding to the actual 
assessment 
5=Awake, following commands 
4=Responds to name spoken in normal tone 
3=Responds only after name is spoken loudly 
and repeatedly or both 
2=Responds only after mild prodding/ 
shaking 
1=Does not respond to mild prodding/shaking 
                / 
                 

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P9 What is the level of your strength now? 
Please record the number 
corresponding to the actual 
assessment 
3= No weakness 
2= A little weak 
1= Very weak 
Nociceptive Factorsa,b,c,e,f 
N1 I am going to show you a series of faces 
and I would like you to indicate which face, 
number or description most accurately 
describes your level of pain at the moment.  
 
N2 I am going to show you a series of faces 
and I would like you to indicate which face, 
number, or description most accurately 
describes your level of feeling nauseous or 
vomiting at the moment.  
 
N3 Sore throat 
Please record the number 
corresponding to the actual 
assessment  
0= No sore throat 
1= Mild sore throat (complains of sore throat 
only on asking) 
2= Moderate sore throat (complains of sore 
throat on his/her own) 
3= Severe sore throat (change of voice or 
hoarseness, associated with throat pain) 
N4 Hoarseness 
Please record the number 
corresponding to the actual 
assessment  
0= No hoarseness 
1= Hoarseness at the time of interview, but 
noted only the patient 
2= Hoarseness that is readily apparent, but 
mild 
3=Hoarseness that is readily apparent and 
severe or aphonia 
Emotional Factorsa,b 
E1 I am going to show you a series of faces 
and I would like you to indicate which face, 
number, or description accurately describes 
to what extent you feel sad, low, or 
depressed at the moment.  
 
E2 I am going to show you a series of faces 
and I would like you to indicate which face, 
number, or description accurately describes 
to what extent you feel anxious or nervous at 
the moment.  
 
E3 What is the overall level of satisfaction 
with your immediate postoperative recovery 
(from the time surgery ended until now)- *T80 
assessment only 
1-100 scale 
100 = “completely satisifed” 
90 = “mostly satisfied” 
80 = “moderately satisfied” 
70 = “minimally satisfied” 
< 70 = “not satisfied” and write reason 
here________________________________ 
a. 
Patient questionnaire adapted from Royse et al. 2010 and Amorim et al. 2014 
b. 
Pain, depression, and anxiety scales are modified from Wong and Baker 1988 
c. 
Nausea scale is modified from Baxter et al. 2011 
d. 
Alertness scale adapted from Doufas et al. 2001 
e. 
Sore throat scale adapted from Chattopadhyay 2017 
f. 
Hoarseness scale adapted from Park 2010