We hypothesized that anesthetized, apneic children could be ventilated equivalently or more efficiently by nasal mask ventilation (NMV) than face mask ventilation (FMV). The aim of this randomized controlled study was to test this hypothesis by comparing the expiratory tidal volume (Vte) between NMV and FMV.Methods:
After the induction of anesthesia, 41 subjects, 3–17 years of age without anticipated difficult mask ventilation, were randomly assigned to receive either NMV or FMV with neck extension. Both groups were ventilated with pressure control ventilation (PCV) at 20 cmH2O of peak inspiratory pressure (PIP) with positive end-expiratory pressure (PEEP) levels of 0, 5, and 10 cmH2O. An additional mouth closing maneuver (MCM) was applied for the NMV group.Results:
The Vte was higher in the FMV group compared with the NMV group (median difference [95% CI]: 8.4 [5.5–11.6] ml·kg−1; P < 0.001) when MCM was not applied. NMV achieved less PEEP than FMV (median difference [95% CI]: 5.0 [4.3–5.3] cmH2O at 10 cmH2O; P < 0.001) though both groups achieved the set PIP level. In the NMV group, MCM markedly increased Vte (median increase [95% CI]: 5.9 [2.5–9.0] ml·kg−1; P < 0.005) and PEEP (median increase [95% CI]: 5.0 [0.6–8.6] cmH2O at 10 cmH2O; P < 0.005); however, PEEP was highly variable and lower than that of FMV (median difference [95% CI]: 2.5 [0.8–8.5] cmH2O at 10 cmH2O; P < 0.05).Conclusions:
In anesthetized, apneic children greater than 2 years of age ventilated with an anesthesia ventilator and neck extension, FMV established a greater Vte than NMV regardless of mouth status. NMV could not maintain the set PEEP level due to an air leak from the mouth. The MCM increased the Vte and PEEP.