Intubation of Obese Patients in the Operating Room With or Without Face Mask Ventilation

Anesthesia consultation or pre-anesthesia visit:

* screening for inclusion and non-inclusion criteria
* patient information
* collection of consent
* inclusion

D0 (day of inclusion):

* before general anesthesia : collection of epidemiological data (history + clinical examinations) + randomization (Arm A/Not Vent : intubation without ventilation or Arm B/Vent : intubation with ventilation)
* general anesthesia : intubation according to randomization arm + collection primary endpoint + conduct of the intubation procedure + morbidity of the intubation procedure
* after general anesthesia : collection of secondary endpoints + conduct of the intubation procedure + morbidity of the intubation procedure + intraoperative respiratory morbidity
* post-interventional care room : collection of clinical parameters in the ICU : postoperative morbidity + study discharge (hospital discharge)

• No ventilation with face mask (Procedure): During the period of apnea (in general anesthesia), the patient did not help with face mask
• Ventilation with face mask (Procedure): During the pperiod of apnea (in general anesthesia), the patient did help with face mask

Primary outcomes

• To compare the effectiveness of an intubation sequence "with ventilation during apnea" versus a sequence "without ventilation during apnea" in preventing complications related to intubation of the obese patient in the operating room [From induction of general anesthesia to 10 minutes after intubation]: Comparison of the incidence of intubation-related complications. Complications identified for the primary endpoint will be: desaturations < 95%, need for 2 or more intubation attempts (including alternative technique), occurrence of inhalation/regurgitation or hypotension with systolic blood pressure < 80 mmHg, with or without amine. Complications will be recorded from induction of general anesthesia to 10 minutes after intubation

Secondary outcomes

• Impact of the nature of the intubation sequence on the progress of the intubation procedure between patient with face mask and patient without face mask [During the general anesthesia, up to 8 hours]: Difficulty with mask ventilation (yes/no)
• Impact of the nature of the intubation sequence on the progress of the intubation procedure between patient with face mask and patient without face mask [During the general anesthesia, up to 10 minutes]: Measure of the saturation before the first laryngoscopy with oximeter
• Impact of the nature of the intubation sequence on the progress of the intubation procedure between patient with face mask and patient without face mask [During the general anesthesia, up to 10 minutes]: Measure of the lowest saturation during the intubation procedure and the following 10 minutes
• Impact of the nature of the intubation sequence on the progress of the intubation procedure between patient with face mask and patient without face mask [During the general anesthesia, up to 8 hours]: Quality of exposure under laryngoscopy (position of the patient)
• Impact of the nature of the intubation sequence on the progress of the intubation procedure between patient with face mask and patient without face mask [During the general anesthesia, up to 8 hours]: Difficulties in intubation (yes/no)
• Impact of the nature of the intubation sequence on the progress of the intubation procedure between patient with face mask and patient without face mask [During the general anesthesia, up to 8 hours]: Description of intubation (mandrin, videolaryngoscope, videolaryngoscope)
• Impact of the nature of the intubation sequence on morbidity related to the intubation procedure between patient with face mask and patient without face mask [up to 8 hours]: Rate of desaturation <80% (yes/no)
• Impact of the nature of the intubation sequence on morbidity related to the intubation procedure between patient with face mask and patient without face mask [up to 8 hours]: Rate of desaturation <90% (yes/no)
• Impact of the nature of the intubation sequence on morbidity related to the intubation procedure between patient with face mask and patient without face mask [up to 8 hours]: Presence of severe hypotension during intubation and in the following hour defined by a systolic blood pressure < 80 mmHg, with or without amine (yes/no)
• Impact of the nature of the intubation sequence on morbidity related to the intubation procedure between patient with face mask and patient without face mask [up to 8 hours]: Number of participants with cardiac arrest
• Impact of the nature of the intubation sequence on morbidity related to the intubation procedure between patient with face mask and patient without face mask [up to 8 hours]: Death during intubation
• Impact of the nature of the intubation sequence on morbidity related to the intubation procedure between patient with face mask and patient without face mask [up to 8 hours]: Difficulties in intubations (yes/no) with the number of intubation attempts
• Impact of the nature of the intubation sequence on morbidity related to the intubation procedure between patient with face mask and patient without face mask [up to 8 hours]: Number of participants with cardiac rhythm disorders
• Impact of the nature of the intubation sequence on morbidity related to the intubation procedure between patient with face mask and patient without face mask [up to 8 hours]: Number of participants with esophageal intubations
• Impact of the nature of the intubation sequence on morbidity related to the intubation procedure between patient with face mask and patient without face mask [up to 8 hours]: Number of participants with regurgitation/inhalation
• Impact of the nature of the intubation sequence on morbidity related to the intubation procedure between patient with face mask and patient without face mask [up to 8 hours]: Number of participants with dental breaks
• Impact of the nature of the intubation sequence on immediate intraoperative and postoperative respiratory morbidity between patient with face mask and patient without face mask [5 minutes, 30 minutes and 1 hour after intubation]: Need for FiO2 >50% during surgery to achieve >95% saturation (yes/no)
• Impact of the nature of the intubation sequence on immediate intraoperative and postoperative respiratory morbidity between patient with face mask and patient without face mask [up to 28 days]: Length of stay in the post-operation monitoring room
• Impact of the nature of the intubation sequence on immediate intraoperative and postoperative respiratory morbidity between patient with face mask and patient without face mask [up to 28 days]: Duration of postoperative mechanical ventilation(in minutes)
• Impact of the nature of the intubation sequence on immediate intraoperative and postoperative respiratory morbidity between patient with face mask and patient without face mask [up to 28 days]: Number of participants with nausea
• Impact of the nature of the intubation sequence on immediate intraoperative and postoperative respiratory morbidity between patient with face mask and patient without face mask [up to 28 days]: Number of participants with vomiting
• Impact of the nature of the intubation sequence on immediate intraoperative and postoperative respiratory morbidity between patient with face mask and patient without face mask [up to 28 days]: Length of hospitalization since randomization
• Impact of the nature of the intubation sequence on immediate intraoperative and postoperative respiratory morbidity between patient with face mask and patient without face mask [up to 28 days]: Hospital discharge status (dead/alive)

Sex: All, ages: 18 Years to any

Inclusion criteria:

* patient requiring general anesthesia with intubation for surgery or scheduled endoscopic procedures
* age > 18 years
* with a BMI superior or equal to 35kg.m-²
* patient having signed an informed consent

Non-inclusion criteria:

* ambient air saturation <90%
* urgent surgery < 24 hours
* cardio-thoracic surgery
* mask ventilation not possible (e.g. ATCD, cervical irradiation, fixed mandible)
* formal contraindication to mask ventilation (e.g. occlusive syndrome, non fasting patient, symptomatic gastroesophageal reflux untreated or persistent under treatment)
* wish of the operator for high flow oxygen preoxygenation
* wish of an intubation without curare by the operator
* pregnant or breast-feeding women
* protected adults (guardianship, curatorship or safeguard of justice)
* participation in another randomized clinical research study concerning preoxygenation and relevant to the primary endpoint
* absence of affiliation to the French social security system

• Results publication: Znaidi S, Deransy R, Asehnoune K, Le Penndu M, Rozec B, Jumel G, Lasocki S, Cadic-Pelletier A, Guinot PG, Duchalais A, Cirenei C, Abrard S, Beloeil H, Fortuit C, Landrin J, Porta Bonete G, Defrancq F, Pere M, Vourc'h M. Intubation of obese patients in the operating room with or without bag-mask ventilation: study protocol for a randomized multicenter trial (VENT OR NOT). Trials. 2025 Nov 11;26(1):492. doi: 10.1186/s13063-025-09114-z. PMID 41219812

• Mickael VOURC'H, PhD, Principal investigator, Nantes University Hospital