Effects of bed height on the performance of endotracheal intubation and bag mask ventilation

Abstract

Objectives. This study was performed to evaluate whether different bed heights affect the performance of airway procedures. Methods. Thirty three medical doctors performed endotracheal intubation (EI) and bag mask ventilation (BMV) using three different bed heights; knee height, mid-thigh height, and anterior superior iliac spine (ASIS) height. For El, performance was assessed based on intubation time, intubation success, and damage to teeth. For BMV, performance was assessed based on tidal volume, ventilation rate, peak pressure, minute ventilation, and airway opening. In addition, three numeric rating scales (NRS; 1 to 10) were used to assess the level of difficulty for each procedure and the doctors' self-confidence. NRS scoring was based on posture (comfortable to uncomfortable), handling (easy to hard), and visual field (good to bad). Results. No significant differences in performance were observed for El or BMV at the three different bed heights. However, all of the NRS scores were significantly different among the different bed heights (P<0.001), and were poorest for the knee height beds: knee height (EI: posture 5.8 similar to 7.3, handling 4.3 similar to 5.7, visual field 3.9 similar to 5.5; BMV: posture 7.1 similar to 8.0, handling 5.9 similar to 7.2, 95% CI), mid-high height (EI: posture 2.9 similar to 4.0, handling 2.9 similar to 4.0, visual field 2.7 similar to 3.8; BMV: posture 2.4 similar to 3.2, handling 2.3 similar to 3.5) and ASIS height (EI: posture 2.2 similar to 3.5, handling 2.6 similar to 3.8, visual field 2.1 similar to 3.4; BMV: posture 2.9 similar to 4.4, handling 4.7 similar to 6.1). Conclusions. Although the participants reported that the knee height beds were the least comfortable, hardest to handle, and made seeing the vocal cord difficult, these caveats did not affect their performance during airway procedures.