Skip to main content

Table 1 Subgroup analysis for study groups

From: Apnoeic oxygenation for emergency anaesthesia of pre-hospital trauma patients

Peri intubation phase 2 min pre to 2 min post intubation   Standard Intervention P value
Median SaO2 (IQR) All patients 100 (96,100) 99 (96,100) p = 0.0001
No hypoxia 100 (98,100) 100 (98,100) p = 1.00
Mild Moderate hypoxia 94 (83,97.75) 94 (88,99) p = 1.00
Severe hypoxia 79 (66.5,86) 83 (77,95) p = 0.28
Total post intubation values / total 90 or less (% difference) All patients 106/653 (16.2) 560/3659 (15.3) 0.546
No hypoxia 24/380 (6.3) 54/1492 (3.6) 0.02
Mild Moderate hypoxia 28/72 (38.9) 131/386 (33.9) 0.947
Severe hypoxia 41/51 (80.4) 118/177 (66.7) 0.195
Total post intubation values / total 85 or less (% difference) All patients 65/653 (10.0) 340/3659 (9.3) 0.864
No hypoxia 7/380 (1.8) 20/1492 (1.3) 0.466
Mild Moderate hypoxia 11/71 (15.3) 61/386 (15.8) 0.947
Severe hypoxia 34/51 (66.7) 100/177 (56.5) 0.195
Post intubation phase (intubation - 10 min) All patients 177/1464 (12.1) 959/8037 (11.9) 0.864
Total post intubation values / total 90 or less (% difference) No hypoxia 43/1126 (3.8) 254/5928 (4.3) 0.476
Mild Moderate hypoxia 39/164 (23.8) 377/1424 (26.5) 0.458
Severe hypoxia 93/160 (58.1) 384/759 (50.6) 0.084
Recovery phase (2 min post intubation to 10 min post intubstion All patients 139/1221 (11.4) 728/6396 (11.4) 0.998
Total post intubation values / total 90 or less (% difference) No hypoxia 33/941 (3.5) 204/5121 (4.0) 0.488
Mild Moderate hypoxia 31/138 (22.5) 280/1128 (24.2) 0.544
Severe hypoxia 73/133 (54.9) 234/746 (31.4) 3.06E-07
Median SpO2 (IQR) All patients 100 (96,100) 99 (96,100) p = 0.0001
No hypoxia 100 (98,100) 100 (98,100) p = 1.00
Mild Moderate hypoxia 94 (83,97.75) 94 (88,99) p = 1.00
Severe hypoxia 79 (66.5,86) 83 (77,95) p = 0.28
Total 90 or less / total peri intubation values (% difference) All patients 106/653 (16.2) 560/3659 (15.3) 0.546
No hypoxia 24/380 (6.3) 54/1492 (3.6) 0.02
Mild Moderate hypoxia 28/72 (38.9) 131/386 (33.9) 0.947
Severe hypoxia 41/51 (80.4) 118/177 (66.7) 0.195
Total 85 or less / total peri intubation values (% difference) All patients 65/653 (10.0) 340/3659 (9.3) 0.864
No hypoxia 7/380 (1.8) 20/1492 (1.3) 0.466
Mild Moderate hypoxia 11/71 (15.3) 61/386 (15.8) 0.947
Severe hypoxia 34/51 (66.7) 100/177 (56.5) 0.195
Post intubation phase (intubation - 10 min) All patients 177/1464 (12.1) 959/8037 (11.9) 0.864
Total 90 or less / total post intubation values (% difference) No hypoxia 43/1126 (3.8) 254/5928 (4.3) 0.476
Mild Moderate hypoxia 39/164 (23.8) 377/1424 (26.5) 0.458
Severe hypoxia 93/160 (58.1) 384/759 (50.6) 0.084
Recovery phase (2 min post intubation to 10 min post intubation) All patients 139/1221 (11.4) 728/6396 (11.4) 0.998
Total 90 or less / total post intubation values (% difference) No hypoxia 33/941 (3.5) 204/5121 (4.0) 0.488
Mild Moderate hypoxia 31/138 (22.5) 280/1128 (24.2) 0.544
Severe hypoxia 73/133 (54.9) 234/746 (31.4) p < 0.0001
  1. Table 1 shows the 2 study groups (standard and intervention) subclassified by the degree of hypoxia was subclassified according to the pre-induction SpO2 value (taken at 0 min) as:
  2. • No hypoxia: SpO2 > 95%
  3. • Mild / moderate hypoxia: SpO2 85–95%
  4. • Severe hypoxia: SpO2 < 85%
  5. The median SpO2 is the median value of all values recorded for the all patients during the peri-intubation phase
  6. The categories reporting ‘total 90 or less’ and ‘total 85 or less’ refer to the number of patients who desaturated in the peri-intubation, post intubation, or recovery phase to an SpO2 or 90% or less, or 85% or less. This figure is reported as a proportion of the number of SpO2 values recorded for all patients in this group and subclassification