TABLE 3

Physiologic Parameters

ParameterT0T1T2
Pao2:Fio2
 Helmet177 (151 to 206)209 (186 to 284)a332 (229 to 418)b
 Mask163 (153 to 190)204 (160 to 215)a320 (266 to 476)b
PaCO2, kPa
 Helmet5.5 (4.6 to 6.3)4.6 (5.1 to 6.1)4.6 (5.1 to 5.8)
 Mask5.0 (3.7 to 5.8)3.9 (4.5 to 5.5)4.1 (5.1 to 6.5)
Arterial pH
 Helmet7.38 (7.32 to 7.40)7.4 (7.36 to 7.49)7.42 (7.40 to 7.43)
 Mask7.37 (7.31 to 7.39)7.43 (7.37 to 7.44)7.41 (7.39 to 7.46)
HR, beats per minute
 Helmet154 (144 to 169)144 (132 to 150)a133 (122 to 140)b
 Mask135 (122 to 145)125 (120 to 132)a115 (100 to 130)b
RR, breaths per minute
 Helmet60 (50 to 70)48 (40 to 55)c40 (35 to 44)b
 Mask60 (35 to 75)40 (20 to 50)c40 (24 to 52)b
Systolic blood pressure, kPa
 Helmet14.6 (12.9 to 15.9)13.9 (13.1 to 14.6)14.6 (13.3 to 14.3)
 Mask13.3 (11.9 to 15.8)13.9 (12.9 to 14.6)14.6 (13.2 to 14.3)
OPS
 Helmet2 (2 to 4)2 (1 to 2)NA
 Mask2 (2 to 3)5 (3 to 6)c,dNA
COMFORT scale
 Helmet20 (18 to 22)16 (16 to 18)NA
 Mask18 (18 to 20)27 (24 to 28)c,dNA
  • Data are expressed as median (interquartile range). T0, baseline; T1, CPAP treatment; T2, spontaneous breathing after 24 h in successfully treated patients (13 in helmet group, 6 in mask group); NA, not applicable. Wilcoxon post hoc analysis and significant comparisons are shown: aP< .05 T1 versus T0, bP < .01 T2 versus T0, cP < .01 T1 versus T0, dP < .01 between groups.