Comparison of Two Types of Face Mask Ventilation in Obese Patients

The aim of the study was to determine which of the tested: cuffed or uncuffed face masks allows better replacement ventilation in obese patients.

The study was conducted on patients with the BMI over 39 kg/m2 Patients qualified for bariatric surgery were selected for this study according to the order of reporting to the surgery department. The study adopted a simplified assumption that the gynoid type of obesity most often concerns women, and the android type, i.e. abdominal obesity, most often affects men. Two face masks were used to compare the effectiveness of replacement ventilation: the cuffed and uncuffed . It was randomly chosen (by tossing a coin) which face mask would be used first. The induction of anesthesia was low-opioid, the patients were placed in the supine position with the head and trunk elevated by 25 degrees on a positioning pad. 100% oxygen concentration was used for active pre-oxygenation, the test mask was applied with one hand using the EC clamp technique. The masks were changed after four consecutive measurements for each type of mask. In order to objectify the measurement with the same tidal volume, a respirator was used with the same settings: Tidal Volume of 500 ml and respiratory rate of 12/min. Sealing was measured by comparing the inspired volume with expired volume, that is the amount of leakage generated by individual masks was assessed. The obtained data were analyzed with the Kolmogorow-Smirnov test and supplemented with the values of the Wilcoxona test.

Inclusion criteria

• obesity
• scheduled for elective surgery under general anesthesia

Exclusion criteria

• predicted difficult intubation
• predicted difficult face-mask ventilation