EPO2-PV: Evaluation of Pre-Oxygenation Conditions in Morbidly Obese Volunteer: Effect of Position and Ventilation Mode

Morbid Obesity Clinical Trial

— EPO2-PV  

Official title:

Evaluation of Different Pre-Oxygenation Conditions in Morbid Obesity: Position and Ventilation Mode, in a Respiratory Physiology Laboratory, on Voluntary Subjects

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02121808
• Other study ID #: IUCPQ 21054
• Status: Completed
• Phase: N/A
• First received: April 22, 2014
• Last updated: September 14, 2017
• Start date: April 2014
• Est. completion date: July 2014

Study information

• Verified date: September 2017
• Source: Laval University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The risk of complications associated with airway management in obese patients is significant. The results of pre-oxygenation allow a prolonged non-hypoxic apnea time for the clinician. The increase in FRC and non-hypoxic apnea time is correlated. The best condition to accomplish the pre-oxygenation in morbidly obese patient is still undetermined in medical literature.

This study is designed to evaluate the effect of different positions combined with different ventilation modes during the pre-oxygenation phase of anesthesia's induction. EPO2: PV will evaluate the effect of different combinations of positions and ventilation modes on pulmonary volumes (mainly functional residual capacity) in a morbidly obese volunteer.

Description:

Complications related to airway management are the major contributing factor to morbidity in anesthesiology. This risk of complications markedly increases when faced with a difficult airway in an obese patient. Pre-oxygenation creates a safety margin by increasing the patient's oxygen stores, through a higher functional residual capacity (FRC). When pre-oxygenated, the clinician may proceed to intubation after a variable period of apnea, while maintaining oxygen saturation over 92%. In non-obese individuals, pre-oxygenation allows a non-hypoxic apnea time of eight minutes. In the obese population, however, this non-hypoxic apnea time decreases to two to three minutes.

Different methods of pre-oxygenation have been proposed in order to increase apnea time before significant oxygen desaturation. Amongst these methods, the following are of particular interest: pre-oxygenation to vital capacity, pre-oxygenation with spontaneous ventilation and positive pressure, and pre-oxygenation with elevated head positioning ("beach-chair"). These methods have been extensively studied in individuals of normal height and weight.

The main objective of pre-oxygenation is to raise oxygen levels available at the alveolar level in order to increase the non-hypoxic apnea time, before a significant desaturation occurs. This raised alveolar oxygen concentration can be done by maintaining a higher inspired oxygen fraction and by promoting a larger FRC which is the oxygen reserve build through the pre-oxygenation phase. In morbid obese patients, these parameters are affected by a lower expiratory flow, lower expiratory flow and closing of small radius airways. The final result probably come from a more cephalad position of the diaphragm induced by a larger intra-abdominal volume.

Actually, different studies demonstrate the advantage of a beach-chair position and non-invasive positive pressure ventilation for pre-oxygenation of obese patients. These advantages are shown by a shorter time of pre-oxygenation to obtain an end-tidal O2 > 90 % and a longer non-hypoxic apnea time (Sat O2 >90%). Up to date, there is no published data on the FRC as a result of different combinations of position and ventilation mode. This study will evaluate FRC by helium dilution technique.

We propose a crossover randomised trial on volunteers waiting for a bariatric surgery. We want to compare, in pre-oxygenation situation, without induction of general anesthesia, the effect of three positions and two ventilation modes on the FRC measure.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 20
• Est. completion date: July 2014
• Est. primary completion date: June 2014
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 21 Years and older

Eligibility

Inclusion Criteria:

• BMI 40 - 80 kg / m2

• Waist circumference: Men: More than 130 cm

• Waist circumference: Women: More than 115 cm

Exclusion Criteria:

• Facial hair

• Cranio-facial abnormality

• Claustrophobia

• Asthma

• COPD (defined by FEV1 < 80 %)

• Severe cardiovascular disease (defined by NYHA =3)

• Pregnancy

• Tobacco use

• NI-CPPV Intolerance documented by a respiratory specialist (pneumologist).

Related Conditions & MeSH terms

• Bariatric Surgery Candidate
• Morbid Obesity
• Obesity
• Obesity, Morbid

Intervention

Procedure:
• NIPPV
Ventilation: non-invasive positive pressure ventilation (NIPPV) Positive end-expiratory pressure: 10 cmH20 Pressure support: 5 - 20 cm H2O for tidal volume of 10 mL / kg (ideal body weight)
• Tidal volume
Tidal volume spontaneous ventilation, no assistance.

Locations

Country	Name	City	State
Canada	Institut universitaire de cardiologie et de pneumologie de Québec	Quebec city	Quebec

Sponsors (1)

Lead Sponsor	Collaborator
Laval University

Country where clinical trial is conducted

Canada, 

References & Publications (18)

Benumof JL, Dagg R, Benumof R. Critical hemoglobin desaturation will occur before return to an unparalyzed state following 1 mg/kg intravenous succinylcholine. Anesthesiology. 1997 Oct;87(4):979-82. — View Citation

Berthoud MC, Peacock JE, Reilly CS. Effectiveness of preoxygenation in morbidly obese patients. Br J Anaesth. 1991 Oct;67(4):464-6. — View Citation

Boyce JR, Ness T, Castroman P, Gleysteen JJ. A preliminary study of the optimal anesthesia positioning for the morbidly obese patient. Obes Surg. 2003 Feb;13(1):4-9. — View Citation

Burns SM, Egloff MB, Ryan B, Carpenter R, Burns JE. Effect of body position on spontaneous respiratory rate and tidal volume in patients with obesity, abdominal distension and ascites. Am J Crit Care. 1994 Mar;3(2):102-6. — View Citation

Campbell IT, Beatty PC. Monitoring preoxygenation. Br J Anaesth. 1994 Jan;72(1):3-4. Erratum in: Br J Anaesth 1994 May;72(5):612. — View Citation

Cheney FW, Posner KL, Lee LA, Caplan RA, Domino KB. Trends in anesthesia-related death and brain damage: A closed claims analysis. Anesthesiology. 2006 Dec;105(6):1081-6. — View Citation

Chung F, Yegneswaran B, Liao P, Chung SA, Vairavanathan S, Islam S, Khajehdehi A, Shapiro CM. STOP questionnaire: a tool to screen patients for obstructive sleep apnea. Anesthesiology. 2008 May;108(5):812-21. doi: 10.1097/ALN.0b013e31816d83e4. — View Citation

Cook TM, Woodall N, Frerk C; Fourth National Audit Project. Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society. Part 1: anaesthesia. Br J Anaesth. 2011 May;106(5):617-31. doi: 10.1093/bja/aer058. Epub 2011 Mar 29. — View Citation

Coussa M, Proietti S, Schnyder P, Frascarolo P, Suter M, Spahn DR, Magnusson L. Prevention of atelectasis formation during the induction of general anesthesia in morbidly obese patients. Anesth Analg. 2004 May;98(5):1491-5, table of contents. — View Citation

Delay JM, Sebbane M, Jung B, Nocca D, Verzilli D, Pouzeratte Y, Kamel ME, Fabre JM, Eledjam JJ, Jaber S. The effectiveness of noninvasive positive pressure ventilation to enhance preoxygenation in morbidly obese patients: a randomized controlled study. Anesth Analg. 2008 Nov;107(5):1707-13. doi: 10.1213/ane.0b013e318183909b. — View Citation

Dixon BJ, Dixon JB, Carden JR, Burn AJ, Schachter LM, Playfair JM, Laurie CP, O'Brien PE. Preoxygenation is more effective in the 25 degrees head-up position than in the supine position in severely obese patients: a randomized controlled study. Anesthesiology. 2005 Jun;102(6):1110-5; discussion 5A. — View Citation

Futier E, Constantin JM, Pelosi P, Chanques G, Massone A, Petit A, Kwiatkowski F, Bazin JE, Jaber S. Noninvasive ventilation and alveolar recruitment maneuver improve respiratory function during and after intubation of morbidly obese patients: a randomized controlled study. Anesthesiology. 2011 Jun;114(6):1354-63. doi: 10.1097/ALN.0b013e31821811ba. — View Citation

Gander S, Frascarolo P, Suter M, Spahn DR, Magnusson L. Positive end-expiratory pressure during induction of general anesthesia increases duration of nonhypoxic apnea in morbidly obese patients. Anesth Analg. 2005 Feb;100(2):580-4. — View Citation

Jense HG, Dubin SA, Silverstein PI, O'Leary-Escolas U. Effect of obesity on safe duration of apnea in anesthetized humans. Anesth Analg. 1991 Jan;72(1):89-93. — View Citation

Juvin P, Lavaut E, Dupont H, Lefevre P, Demetriou M, Dumoulin JL, Desmonts JM. Difficult tracheal intubation is more common in obese than in lean patients. Anesth Analg. 2003 Aug;97(2):595-600, table of contents. — View Citation

Murphy C, Wong DT. Airway management and oxygenation in obese patients. Can J Anaesth. 2013 Sep;60(9):929-45. doi: 10.1007/s12630-013-9991-x. Epub 2013 Jul 9. — View Citation

Parameswaran K, Todd DC, Soth M. Altered respiratory physiology in obesity. Can Respir J. 2006 May-Jun;13(4):203-10. Review. — View Citation

Tanoubi I, Drolet P, Donati F. Optimizing preoxygenation in adults. Can J Anaesth. 2009 Jun;56(6):449-66. doi: 10.1007/s12630-009-9084-z. Epub 2009 Apr 28. Review. — View Citation

* Note: There are 18 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Vital Signs	Change in vital signs before and after the pre-oxygenation phase in the 6 combinations after a 5 minutes pre-oxygenation period in the 6 combinations previously described.	At the end of a 5 minutes pre-oxygenation period
Primary	Functional Residual Capacity	Change of functional residual capacity (FRC), in obese patient, as a result of different pre-oxygenation positions; 1- supine, 2-beach-chair, 3- reverse Trendelenburg, in two different ventilation modes : 1- spontaneous ventilation at tidal volume, 2- non-invasive positive pressure ventilation with inspiratory assistance.	After a 5 minutes pre-oxygenation period
Secondary	Diaphragmatic Amplitude.	Evaluation of changes in diaphragmatic amplitude and movement determined by fluoroscopy imaging after a 5 minutes pre-oxygenation period in the 6 combinations previously described.	After a 5 minutes pre-oxygenation period
Secondary	Respiratory Mechanics	Change in respiratory mechanics (compliance, resistance, tidal volume, positive end-expiratory pressure, maximal inspiratory pressure) evaluated at the end of a 5 minutes pre-oxygenation period in the 6 combinations previously described.	At the end of a 5 minutes pre-oxygenation period
Secondary	Patient's Comfort	Evaluation of the patient's comfort at the end of each intervention on an analog visual scale after a 5 minutes pre-oxygenation period in the 6 combinations previously described.	At the end of a 5 minutes pre-oxygenation period