| 1 Inhospital case fatality rate |
8 |
10148 |
Peto Odds Ratio (Peto, Fixed, 95% CI) |
0.87 [0.61, 1.26] |
| 2 Pneumonia |
8 |
2699 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.68 [1.00, 2.81] |
| 3 Pulmonary atelectasis |
5 |
2400 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.57 [1.18, 2.10] |
| 4 Myocardial infarction |
6 |
9246 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.01 [0.84, 1.22] |
| 5 Stroke |
4 |
9142 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.47 [0.86, 2.53] |
| 6 Severe nausea and vomiting |
10 |
11045 |
Odds Ratio (M‐H, Random, 95% CI) |
1.44 [0.97, 2.15] |
| 7 Venous thromboembolism |
2 |
9004 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.73 [0.45, 1.20] |
| 8 Wound infection rate |
6 |
9789 |
Odds Ratio (M‐H, Random, 95% CI) |
1.22 [0.84, 1.78] |
| 9 Length of hospital stay |
6 |
1103 |
Mean Difference (IV, Random, 95% CI) |
0.36 [‐0.69, 1.40] |
| 10 Inhospital case fatality rate: type of surgery |
4 |
646 |
Peto Odds Ratio (Peto, Fixed, 95% CI) |
0.64 [0.11, 3.88] |
| 10.1 Intra‐abdominal surgery |
2 |
499 |
Peto Odds Ratio (Peto, Fixed, 95% CI) |
0.41 [0.06, 3.03] |
| 10.2 Neurosurgery |
2 |
147 |
Peto Odds Ratio (Peto, Fixed, 95% CI) |
4.45 [0.07, 287.21] |
| 11 Pneumonia: type of surgery |
6 |
427 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.29 [0.48, 3.48] |
| 11.1 Intra‐abdominal surgery |
3 |
193 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.12 [0.33, 3.78] |
| 11.2 Neurosurgery |
3 |
234 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.71 [0.30, 9.81] |
| 12 Pulmonary atelectasis: type of surgery |
3 |
128 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.16 [0.02, 1.06] |
| 12.1 Intra‐abdominal surgery |
2 |
102 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.16 [0.02, 1.06] |
| 12.2 Neurosurgery |
1 |
26 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.0 [0.0, 0.0] |
| 13 Myocardial infarction: type of surgery |
3 |
212 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.24 [0.42, 3.67] |
| 13.1 Intra‐abdominal surgery |
1 |
91 |
Odds Ratio (M‐H, Fixed, 95% CI) |
2.07 [0.48, 8.93] |
| 13.2 Neurosurgery |
1 |
87 |
Odds Ratio (M‐H, Fixed, 95% CI) |
3.44 [0.14, 86.92] |
| 13.3 Vascular surgery |
1 |
34 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.25 [0.02, 2.74] |
| 14 Stroke: type of surgery |
2 |
138 |
Odds Ratio (M‐H, Fixed, 95% CI) |
2.46 [0.53, 11.48] |
| 14.1 Neurosurgery |
1 |
87 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.74 [0.28, 10.95] |
| 14.2 Ophthalmic surgery |
1 |
51 |
Odds Ratio (M‐H, Fixed, 95% CI) |
5.20 [0.24, 113.98] |
| 15 Severe nausea and vomiting: type of surgery |
8 |
2041 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.13 [0.72, 1.78] |
| 15.1 Day‐case procedure/examination |
4 |
1624 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.65 [0.30, 1.41] |
| 15.2 Intra‐abdominal surgery |
3 |
233 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.56 [0.65, 3.71] |
| 15.3 Breast surgery |
1 |
184 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.44 [0.70, 2.99] |
| 16 Wound infection rate: type of surgery |
3 |
525 |
Odds Ratio (M‐H, Random, 95% CI) |
1.63 [0.28, 9.33] |
| 16.1 Intra‐abdominal surgery |
2 |
499 |
Odds Ratio (M‐H, Random, 95% CI) |
1.63 [0.28, 9.33] |
| 16.2 Neurosurgery |
1 |
26 |
Odds Ratio (M‐H, Random, 95% CI) |
0.0 [0.0, 0.0] |
| 17 Length of hospital stay: type of surgery |
3 |
556 |
Mean Difference (IV, Fixed, 95% CI) |
‐0.45 [‐1.44, 0.54] |
| 17.1 Intra‐abdominal surgery |
2 |
530 |
Mean Difference (IV, Fixed, 95% CI) |
‐0.12 [‐1.25, 1.00] |
| 17.2 Neurosurgery |
1 |
26 |
Mean Difference (IV, Fixed, 95% CI) |
‐1.60 [‐3.71, 0.51] |
| 18 Inhospital case fatality rate: concentrations of inhaled nitrous oxide |
7 |
9920 |
Peto Odds Ratio (Peto, Fixed, 95% CI) |
0.86 [0.60, 1.24] |
| 18.1 High‐concentration nitrous oxide |
7 |
9920 |
Peto Odds Ratio (Peto, Fixed, 95% CI) |
0.86 [0.60, 1.24] |
| 19 Stroke: concentrations of inhaled nitrous oxide |
3 |
9091 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.39 [0.80, 2.42] |
| 19.1 High‐concentration nitrous oxide |
3 |
9091 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.39 [0.80, 2.42] |
| 20 Severe nausea and vomiting: concentrations of inhaled nitrous oxide |
8 |
10847 |
Odds Ratio (M‐H, Random, 95% CI) |
1.37 [0.89, 2.11] |
| 20.1 High‐concentration nitrous oxide |
7 |
10691 |
Odds Ratio (M‐H, Random, 95% CI) |
1.34 [0.81, 2.19] |
| 20.2 Low‐concentration nitrous oxide |
2 |
156 |
Odds Ratio (M‐H, Random, 95% CI) |
1.39 [0.53, 3.68] |
| 21 Length of hospital stay: concentrations of inhaled nitrous oxide |
5 |
875 |
Mean Difference (IV, Random, 95% CI) |
0.45 [‐1.03, 1.93] |
| 21.1 High‐concentration nitrous oxide |
5 |
875 |
Mean Difference (IV, Random, 95% CI) |
0.45 [‐1.03, 1.93] |
| 22 Inhospital case fatality rate: techniques used in the nitrous oxide‐free group |
6 |
1144 |
Peto Odds Ratio (Peto, Fixed, 95% CI) |
1.33 [0.29, 6.00] |
| 22.1 Propofol‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
1 |
121 |
Peto Odds Ratio (Peto, Fixed, 95% CI) |
4.45 [0.07, 287.21] |
| 22.2 Volatile anaesthetic‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
5 |
1023 |
Peto Odds Ratio (Peto, Fixed, 95% CI) |
1.11 [0.22, 5.58] |
| 23 Pneumonia: techniques used in the nitrous oxide‐free group |
7 |
687 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.13 [0.45, 2.86] |
| 23.1 Propofol‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
2 |
181 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.50 [0.07, 3.61] |
| 23.2 Volatile anaesthetic‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
5 |
506 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.42 [0.49, 4.06] |
| 24 Pulmonary atelectasis: techniques used in the nitrous oxide‐free group |
4 |
388 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.32 [0.09, 1.12] |
| 24.1 Propofol‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
2 |
102 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.16 [0.02, 1.06] |
| 24.2 Volatile anaesthetic‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
2 |
286 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.70 [0.12, 4.29] |
| 25 Myocardial infarction: techniques used in the nitrous oxide‐free group |
4 |
242 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.96 [0.37, 2.53] |
| 25.1 Volatile anaesthetic‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
4 |
242 |
Odds Ratio (M‐H, Fixed, 95% CI) |
0.96 [0.37, 2.53] |
| 26 Stroke: techniques used in the nitrous oxide‐free group |
2 |
138 |
Odds Ratio (M‐H, Fixed, 95% CI) |
2.46 [0.53, 11.48] |
| 26.1 Propofol‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
1 |
51 |
Odds Ratio (M‐H, Fixed, 95% CI) |
5.20 [0.24, 113.98] |
| 26.2 Volatile anaesthetic‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
1 |
87 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.74 [0.28, 10.95] |
| 27 Severe nausea and vomiting: techniques used in the nitrous oxide‐free group |
8 |
2041 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.13 [0.72, 1.78] |
| 27.1 Propofol‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
1 |
1417 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.99 [0.18, 22.04] |
| 27.2 Volatile anaesthetic‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
7 |
624 |
Odds Ratio (M‐H, Fixed, 95% CI) |
1.11 [0.70, 1.75] |
| 28 Wound infection rate: techniques used in the nitrous oxide‐free group |
4 |
785 |
Odds Ratio (M‐H, Random, 95% CI) |
2.13 [0.44, 10.22] |
| 28.1 Volatile anaesthetic‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
4 |
785 |
Odds Ratio (M‐H, Random, 95% CI) |
2.13 [0.44, 10.22] |
| 29 Length of hospital stay: techniques used in the nitrous oxide‐free group |
5 |
1044 |
Mean Difference (IV, Fixed, 95% CI) |
0.20 [‐0.36, 0.75] |
| 29.1 Volatile anaesthetic‐based maintenance of anaesthesia used in the nitrous oxide‐free group |
5 |
1044 |
Mean Difference (IV, Fixed, 95% CI) |
0.20 [‐0.36, 0.75] |
