A randomized comparison of volume- and pressure-controlled ventilation in children with the i-gel: Effects on peak inspiratory pressure, oropharyngeal leak pressure, and gastric insufflation

Comparison of Gastric Insufflation Volume Between Ambu AuraGain and ProSeal Laryngeal Mask Airway Using Ultrasonography in Patients Undergoing General Anesthesia: A Randomized Controlled Trial

Introduction: Ambu AuraGain and ProSeal laryngeal mask airway are second-generation supraglottic airway devices (SADs) with added advantage of gastric drain and better oropharyngeal sealing pressure. The primary objective was to study the difference in the gastric insufflation volume between Ambu AuraGain and ProSeal LMA in patients undergoing general anesthesia.

Methods: This randomized controlled trial involving 120 adult patients scheduled under general anesthesia were randomized into either Ambu AuraGain or LMA ProSeal group. Gastric cross-sectional area was measured using ultrasonography at baseline, after mask ventilation, and at the end of surgery. Gastric volume was calculated from the measured cross-sectional area. Oropharyngeal sealing pressure, peak airway pressure, and postoperative complications were noted. Statistical analysis was done using SPSS version 22 (Armonk, NY: IBM Corp.) and p < 0.05 was considered statistically significant.

Results: Demographic profile of the study groups was comparable. There was a significant difference in gastric volume between the groups at the end of surgery with 5.91 ml (±9.68 ml) in Ambu AuraGain group and 12.28 ml (±13.05 ml) in the LMA ProSeal group (p = 0.001). Similarly, there was a difference in volume between baseline and at the end of the surgery within the groups also (Ambu AuraGain group, p=0.0012; LMA ProSeal group, p=0.0015, respectively). Though the oropharyngeal sealing pressure and peak airway pressures were comparable, increased incidence of postoperative complications was observed with LMA ProSeal.

Conclusion: Thus, Ambu AuraGain resulted in a lower gastric insufflation volume than LMA ProSeal with lesser incidence of postoperative complications.

Effect of facemask ventilation with different ventilating volumes on gastric insufflation during anesthesia induction in patients undergoing laparoscopic cholecystectomy

Objectives:

To compare the occurrence of gastric insufflation during anesthesia induction in patients undergoing laparoscopic cholecystectomy, using facemask ventilation with different ventilation volumes.

Methods:

This is a prospective study of 54 patients undergoing laparoscopic cholecystectomy under general anesthesia between January 2018 and June 2018. Facemask ventilation with volume mode controlled at 6 ml/kg (group V6), 8 ml/kg (group V8) or 10 ml/kg (group V10) was applied for 120 seconds (sec) during anesthesia induction. Before facemask ventilation and at 120 sec of facemask ventilation, gastric insufflation was determined by ultrasonography. Gastric insufflation was also evaluated using direct vision of laparoscopy. Respiratory parameters were monitored.

Results:

The incidence of gastric insufflation in group V10 (55.6%) was significantly higher than that in groups V6 (11.1%) and V8 (16.7%). However, it showed no significant difference between groups V6 and V8. During facemask ventilation for 120 sec, carbon dioxide accumulation trend occurred in group V6, and group V10 exhibited evidence of hyper-ventilation. Group V8 might be considered the best balance between low gastric insufflation and effective lung ventilation.

Conclusion:

Facemask ventilation with a ventilation volume of 8 ml/kg seems to have adequate preoxygenation and avoid excessive gastric insufflation during anesthesia induction in laparoscopic cholecystectomy.