Multi-Strategy Intervention for Anesthesia Care of Obese Patients A Factorial Randomized Controlled Trial

Summary

The main objective of this study is to investigate the optimal anesthesia for obese patients undergoing bariatric surgery in the strategies of positive pulmonary ventilation, tracheal intubation technique, hemodynamic monitoring, and postoperative nausea and vomiting (PONV) prophylaxis, as the followed:

1. To evaluate the effectiveness and adverse effect of intravenous dexamethasone for PONV prophylaxis
2. To determine the safe inspiratory pressure to prevent the occurrence of gastric insufflation during facemask ventilation using point-of-care ultrasonography of antrum
3. To compare the effectiveness and safety between video intubating stylet and video laryngoscope in the placement of tracheal tubes
4. To apply minimally invasive CO monitors in guiding goal-directed hemodynamic therapy and assess its impact on major complications and postoperative recovery

Conditions

• Obesity
• Bariatric Surgery Candidate
• Tracheal Intubation Morbidity
• Nausea and Vomiting, Postoperative
• Hyperglycemia Drug Induced
• Gastric Reflux

Interventions

DRUG

Dexamethasone 8 mg

In the designated patients, 8 mg of dexamethasone or placebo will be given intravenously within 10 minutes after the induction of anesthesia.

DIAGNOSTIC_TEST

Applied inspiratory pressure (10, 15, 20, or 25 cmH2O)

A two-handed head-tilt jaw-thrust maneuver will be performed to establish an open airway. Once apnea determined by end-tidal capnography occurs, a mechanical ventilation with the assigned peak inspiratory pressure will be initiated. The pressure-controlled mode will be used with an inspiratory-to-expiratory ratio of 1:2 and no positive end-expiratory pressure (PEEP), at a frequency of 15 breath·min-1 and with 100% oxygen, by the ventilator (Carestation 620, Datex-Ohmeda, Inc., Madison, WI, USA).

DEVICE

Tracheal intubation using video intubating stylet, video laryngoscopy, or direct laryngoscopy

In video intubating stylet group, a tracheal tube (ConvaTec, Berkshire, England, UK) in appropriate sizes is preloaded over the Trachway® video intubating stylet (TVI-4050, Markstein Sichtec Medical Corp, Taichung, Taiwan), which is introduced into oral cavity to visualize the epiglottis and guided to glottis via a monitor after full neuromuscular blockade is achieved. In video laryngoscopy group, a tracheal tube is preloaded over a GlideRite® stylet, which is specifically designed to work with GlideScope® video laryngoscope (Verathon Medical, Bothell, WA, USA). GlideScope® blade size 3 (GS-3) or 4 (GS-4) is used in all patients. In direct laryngoscopy group, tracheal tubes are prepared with a hockey stick-shaped stylet, and direct laryngoscopy is performed using a size-3 or -4 Macintosh blade (Rüsch Inc., Duluth, GA, USA).

DEVICE

Goal-directed hemodynamic therapy targeting cardiac index

Subjects of the GDHT group will be managed according to the ERAS algorithm utilizing ProAQT® parameters to maintain the cardiac index ≥ 2.5 l·min-1·m-2. In brief, if cardiac index \< 2.5 l·min-1·m-2, a bolus of 150 ml of crystalloid fluid will be given until the stroke volume variation is \< 10%. If cardiac index \< 2.5 l·min-1·m-2 despite the stroke volume variation of ≥ 10% following fluid challenge, continuous intravenous infusion of dopamine 5-10 μg·kg-1·min-1 will be administered. If mean arterial pressure is \< 70 mmHg despite cardiac index ≥ 2.5 l·min-1·m-2, intravenous infusion of norepinephrine 2-10 μg·min-1 will be used.

DRUG

Placebo (0.9% sodium chloride)

Placebo of 0.9% sodium chloride will be given intravenously within 10 minutes after the induction of anesthesia.

Sponsors & Collaborators

• YingHsuanTai

  lead OTHER

Principal Investigators

• Ying-Hsuan Tai, M.D. · Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

FACTORIAL

Eligibility

Min Age

20 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2022-05-31

Primary Completion

2023-08-31

Completion

2023-08-31

Countries

• Taiwan

Study Locations