Table 3.
Secondary outcomes (intention-to-treat population)
| n | Summary measure | Effect measure | 95% CI | p value | |
|---|---|---|---|---|---|
| Duration of ICU stay, days* | |||||
| Sham | 135 | 16·0 (8·0–23·0) | .. | .. | .. |
| Intrathecal | 136 | 13·5 (8·0–21·0) | .. | .. | 0·07 |
| Equine intramuscular | 108 | 14·0 (8·0–22·0) | .. | .. | .. |
| Human intramuscular | 109 | 13·0 (7·0–22·0) | .. | .. | 0·68 |
| Duration of hospital stay, days* | |||||
| Sham | 135 | 24·0 (17·0–31·0) | .. | .. | .. |
| Intrathecal | 136 | 23·0 (18·0–29·3) | .. | .. | 0·23 |
| Equine intramuscular | 108 | 23·0 (17·0–30·0) | .. | .. | .. |
| Human intramuscular | 109 | 23·0 (17·0–30·0) | .. | .. | 0·85 |
| Duration of mechanical ventilation, days*† | |||||
| Sham | 69 | 17·0 (12·3–22·8) | .. | .. | .. |
| Intrathecal | 62 | 16·0 (11·0–21·0) | .. | .. | 0·46 |
| Equine intramuscular | 48 | 17·0 (12·3–22·8) | .. | .. | .. |
| Human intramuscular | 50 | 16·0 (11·0–21·0) | .. | .. | 0·71 |
| In-hospital deaths‡ | |||||
| Sham | 135 | 4 (3%) | .. | .. | .. |
| Intrathecal | 136 | 3 (2%) | OR 0·74 | 0·14 to 3·41 | 0·70 |
| Equine intramuscular | 108 | 4 (4%) | .. | .. | .. |
| Human intramuscular | 109 | 2 (2%) | OR 0·49 | 0·07 to 2·54 | 0·41 |
| 240-day deaths§ | |||||
| Sham | 134 | 6 (4%) | .. | .. | .. |
| Intrathecal | 134 | 5 (4%) | OR 0·82 | 0·23 to 2·79 | 0·75 |
| Equine intramuscular | 107 | 6 (6%) | .. | .. | .. |
| Human intramuscular | 107 | 4 (4%) | OR 0·65 | 0·16 to 2·33 | 0·51 |
| 240-day Rankin score,¶severe (score >2) | |||||
| Sham | 134 | 18 (13%) | .. | .. | .. |
| Intrathecal | 134 | 11 (8%) | OR 0·58 | 0·25 to 1·26 | 0·17 |
| Equine intramuscular | 107 | 14 (13%) | .. | .. | .. |
| Human intramuscular | 107 | 9 (8%) | OR 0·61 | 0·24 to 1·46 | 0·28 |
| Ventilator-associated pneumonia†‡ | |||||
| Sham | 69 | 30 (43%) | .. | .. | .. |
| Intrathecal | 62 | 26 (42%) | OR 0·94 | 0·47 to 1·88 | 0·86 |
| Equine intramuscular | 48 | 20 (42%) | .. | .. | .. |
| Human intramuscular | 50 | 25 (50%) | OR 1·40 | 0·63 to 3·13 | 0·41 |
| Microbiologically confirmed ventilator-associated pneumonia‡ | |||||
| Sham | 69 | 24 (35%) | .. | .. | .. |
| Intrathecal | 62 | 21 (34%) | OR 0·96 | 0·46 to 1·98 | 0·91 |
| Equine intramuscular | 48 | 16 (33%) | .. | .. | .. |
| Human intramuscular | 50 | 21 (42%) | OR 1·45 | 0·64 to 3·33 | 0·38 |
| New antibiotics during hospitalisation‡ | |||||
| Sham | 135 | 61 (45%) | .. | .. | .. |
| Intrathecal | 136 | 51 (38%) | OR 0·73 | 0·45 to 1·18 | 0·20 |
| Equine intramuscular | 108 | 40 (37%) | .. | .. | .. |
| Human intramuscular | 109 | 44 (40%) | OR 1·15 | 0·67 to 1·99 | 0·61 |
| Autonomic nervous system dysfunction‡ | |||||
| Sham | 135 | 28 (21%) | .. | .. | .. |
| Intrathecal | 136 | 28 (21%) | OR 0·99 | 0·55 to 1·79 | 0·98 |
| Equine intramuscular | 108 | 22 (20%) | .. | .. | .. |
| Human intramuscular | 109 | 21 (19%) | OR 0·93 | 0·48 to 1·82 | 0·84 |
| Total dose pipecuronium, mg‖ | |||||
| Sham | 69 | 386 (162–646) | .. | .. | .. |
| Intrathecal | 62 | 452 (222–637) | Beta 1·5 | −1·6 to 4·6 | 0·343 |
| Equine intramuscular | 48 | 376 (147–624) | .. | .. | .. |
| Human intramuscular | 50 | 444 (114–713) | Beta 0·3 | −3·5 to 4·1 | 0·877 |
| Duration of pipecuronium, days‖ | |||||
| Sham | 69 | 11·0 (6·0–17·0) | .. | .. | .. |
| Intrathecal | 62 | 13·5 (8·0–17·0) | Beta 1·0 | −1·4 to 3·4 | 0·419 |
| Equine intramuscular | 48 | 11·0 (5·8–17·0) | .. | .. | .. |
| Human intramuscular | 50 | 11·5 (5·3–18·0) | Beta 0·5 | −2·5 to 3·5 | 0·734 |
| Total benzodiazepines, mg‖ | |||||
| Sham | 135 | 4718 (1686–9224) | .. | .. | .. |
| Intrathecal | 136 | 4817 (1858–8327) | Beta −0·5 | −7·7 to 6·8 | 0·902 |
| Equine intramuscular | 108 | 3457 (1438–7890) | .. | .. | .. |
| Human intramuscular | 109 | 5588 (1686–9021) | Beta 6·2 | −2·0 to 14·4 | 0·139 |
| Duration of benzodiazepines, days‖ | |||||
| Sham | 135 | 1·40 (1·26–1·51) | .. | .. | .. |
| Intrathecal | 136 | 1·38 (1·28–1·48) | Beta −0·02 | −0·1 to 0·03 | 0·392 |
| Equine intramuscular | 108 | 1·38 (1·26–1·49) | .. | .. | .. |
| Human intramuscular | 109 | 1·38 (1·26–1·49) | Beta −0·004 | −0·063 to 0·055 | 0·884 |
| ICU cost, US$‖** | |||||
| Sham | 135 | 1150 (259–2632) | .. | .. | .. |
| Intrathecal | 136 | 735 (276–2316) | Beta −0·1 | −0·2 to 0·1 | 0·258 |
| Equine intramuscular | 108 | 721 (232–2526) | .. | .. | .. |
| Human intramuscular | 109 | 744 (271–2656) | Beta 0·02 | −0·13 to 0·17 | 0·825 |
| Hospital cost, US$‖** | |||||
| Sham | 135 | 1217 (369–2726) | .. | .. | .. |
| Intrathecal | 136 | 861 (391–2423) | Beta −0·07 | −0·18 to 0·05 | 0·25 |
| Equine intramuscular | 108 | 791 (349–2599) | .. | .. | .. |
| Human intramuscular | 109 | 843 (351–2737) | Beta 0·01 | −0·12 to 0·14 | 0·908 |
Data are median (IQR), or n (%), unless stated otherwise. ICU=intensive care unit. OR=odds ratio. Based on the Box-Cox diagnoses, beta coefficients of groups were compared on a log transformation scale for ICU costs and hospital costs, and on a square root transformation scale for dose of pipecuronium and benzodiazepines to reduce non-normality of the errors in linear regression models.
*
p value relates to cause-specific cumulative incidence tested using Gray's log-rank test.
†
Ventilated patients only.
‡
p value is based on logistic regression model.
§
p value relates to comparison of survival curves using log-rank test.
¶
p value relates to proportional odds logistic regression model.
‖
p value is based on linear regression model.
**
Costs exclude those of antitoxin and any lumbar puncture procedure.