Comparison of gastric insufflation produced during conventional versus modified face mask ventilation during induction of general anaesthesia in obese patients undergoing elective surgery: A prospective randomised double blinded study.
试验速览
- 阶段
- 4 期
- 状态
- 招募中
- 入组人数
- 70
- 试验地点
- 1
- 主要终点
- Number of patients who develop a new ‘comet tail sign’ suggestive of gastric insufflation after induction compared to preinduction
研究概览
简要总结
Peri-operative aspiration of gastric contents is a rare but serious complication under general anaesthesia (GA). Aspiration of gastric contents can result in chemical pneumonitis, atelectasis, ventilation – perfusion mismatch, acute respiratory distress syndrome amongst others. Conventional face mask ventilation (FMV) during induction of GA may result in insufflation of air in to the gastric antrum leading to gastric distention. Therefore, rapid sequence induction (RSI) is commonly used in patients who are at risk of aspiration of gastric content like obese patients, pregnancy, patients with intestinal obstruction, etc.
Obese patients (Body Mass Index
30 Kg/m2) are more prone to pulmonary aspiration compared to patients with normal BMI. This is mainly due to difficult bag and mask ventilation (BMV) resulting in higher gastric insufflation, and increased intraabdominal pressure.It has been shown that conventional FMV used during the induction of anaesthesia puts obese patients at risk of aspiration by causing insufflation of air into the stomach.On the other hand, obese patients may not achieve adequate oxygenation with spontaneous preoxygenation technique, putting them at risk of rapid desaturation. Hence, a modified FMV technique which would provide adequate oxygenation without putting these patients at risk of aspiration is ideal.
Gastric ultrasound (US) has emerged as a non-invasive point of care diagnostic tool which allows for both qualitative detection and quantitative estimation of gastric volume with high sensitivity and specificity.
In this trial, we would like to compare the effect of conventional FMV (Tidal volume of 08 ml/kg and respiratory rate of 16 breaths/min) vs modified FMV (Tidal volume of 4 ml/kg and respiratory rate of 8 breaths/min) technique on gastric insufflation assessed by using gastric ultrasound during induction of GA in obese patients undergoing elective surgery.
Our hypothesis is that modified face mask ventilation technique is superior to conventional face mask ventilation technique in terms of causing lesser gastric insufflation in obese patients without having any deleterious effects on oxygenation and ventilation.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 盲法
- Participant and Investigator Blinded
入排标准
- 年龄范围
- 18.00 Year(s) 至 65.00 Year(s)（—）
- 性别
- All
入选标准
- •Obese patients having BMI between 30 to 49.9 kg/m2 ASA physical status II and III Age between 18 to 65 years of either sex Adequate fasting status (6h for solids and 2h for clear liquids).
排除标准
- •Patients having comet tail appearance prior to induction (baseline) Failure to obtain clear ultrasonographic images Drugs affecting the dynamics of gastrointestinal system History of esophageal or gastrointestinal trauma or surgery Failed facemask ventilation in either group (An experienced anaesthetist fails to maintain SpO2 of above 90% using 100% O2 with bag and mask ventilation with two hand techniques and use of oral airway) More than one attempt at endotracheal intubation Esophageal intubation Occurrence of gastric content regurgitation or aspiration.
结局指标
主要结局
Number of patients who develop a new ‘comet tail sign’ suggestive of gastric insufflation after induction compared to preinduction
时间窗: At 0 and 10 minutes
次要结局
- Change in cross sectional area (CSA) of gastric antrum (measured using gastric ultrasound) and gastric volume (calculated using Bouvet equation) after induction compared to preinduction(At 0 and 10 minutes)
- Change in arterial partial pressure of oxygen (PaO2), carbon dioxide (PaCO2), pH value and bicarbonate (HCO3-) at T1, T2 and T3 time intervals(At 0, 2 and 5 minutes)
- Postoperative symptoms suggestive of gastric distention (bloating, burping, flatulence) and Post-operative Nausea and Vomiting (PONV)(At 0 and 1 hour)
研究者
Dr Ghansham Biyani
All India Institute of Medical Sciences, Mangalagiri