# Table 3 Univariate and multivariate analysis of factors associated with mortality in 261 injured patients undergoing pre-hospital rapid sequence induction of anaesthesia by a helicopter emergency medicine service

Factor

Survived (n = 193)

Died (n = 46)

Univariate analysis

Multivariable analysis

Crude odds ratio (95% CI)

P -value

P -value

Age, years

39 (23 to 55)

51 (40 to 63)

1.029 (1.012, 1.047)

0.001

1.032 (1.006, 1.059)

0.016

Gender

Male

140 (80.9)

33 (19.1)

1.041 (0.509, 2.128)

0.913

Female

53 (80.3)

13 (19.7)

Mechanism of injury

Blunt

183 (79.9)

46 (20.1)

-

0.216

Penetrating

10 (100.0)

0

Initial physiology

Glasgow coma scale

10 (7 to 13)

4 (3 to 10)

0.759 (0.724, 0.874)

<0.0001

0.780 (0.680, 0.896)

<0.0001

Heart rate

90 (76 to 107)

95 (68 to 125)

1.006 (0.993, 1.018)

0.363

Systolic blood pressure

127 (112 to 144)

120 (101 to 144)

0.994 (0.981, 1.007)

0.361

Injury severity score

21 (13 to 34)

34 (27 to 43)

1.077 (1.041, 1.114)

<0.0001

1.054 (1.013, 1.098)

0.009

Rapid sequence induction dose

Full

148 (86.6)

23 (13.4)

3.289 (1.687, 6.410)

<0.0001

1.901 (0.685, 5.272)

0.217

Reduced

45 (66.2)

23 (33.8)

Rapid sequence induction protocol

ES

85 (81.0)

20 (19.0)

1.023 (0.535, 1.869)

1.000

FKR

108 (80.6)

26 (19.4)

Haemodynamic response*

Normal

79 (88.8)

10 (11.2)

1.541 (0.660, 3.601)

0.317

Abnormal

82 (83.7)

16 (16.3)

1. Data are presented as median (range), number (percent), or odds ratio (95%). Categorical variables are presented with each state on a separate row. The odds ratio represents the odds of survival when the first state (first row) is present compared to when the second state (second row) is present. *Calculated for 187 patients with measurable haemodynamic response. Normal (within 20% of baseline blood pressure), Abnormal (not within 20% of baseline blood pressure). Bold values indicate P <0.05. ES, etomidate suxamethonium; FKR, fentanyl ketamine rocuronium.