Summary of findings for the main comparison. PLMA versus tracheal tube for airway management during general anaesthesia in obese participants.
| PLMA versus tracheal tube for airway management during general anaesthesia in obese participants | ||||||
| Patient or population: airway management during general anaesthesia in obese participants Settings: Intervention: PLMA versus tracheal tube | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No. of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| Control | PLMA versus tracheal tube | |||||
| Failed placement/change of device | Not estimable | 118 (2 studies) | ⊕⊕⊝⊝ lowa | 5/118 participants (4.2%) with PLMA required change to tracheal tube (TT) because of failed insertion. No equivalent outcome identified for the TT group | ||
| Episodes of hypoxaemia in PACU < 92% oxygen saturation | 429 per 1000 | 116 per 1000 (43 to 309) | RR 0.27 (0.1 to 0.72) | 70 (1 study) | ⊕⊕⊕⊝ moderateb | |
| Oxygen saturation of peripheral blood (%) in PACU | The mean oxygen saturation of peripheral blood (%) in PACU ranged across control groups from 90.3% to 94.7% | The mean oxygen saturation of peripheral blood (%) in PACU in the intervention groups was 2.54 higher (1.09 to 4 higher) | 204 (2 studies) | ⊕⊕⊝⊝ lowa,c | ||
| Pulmonary aspiration of gastric contents | See comment | See comment | Not estimable | 232 (2 studies) | See comment | No cases of pulmonary aspiration occurred in study populations |
| Serious respiratory complications and mortality－not reported | See comment | See comment | Not estimable | ‐ | See comment | No cases of serious respiratory complications or mortality within 30 days of anaesthesia reported in study populations |
| Laryngospasm/bronchoconstriction between induction and recovery | 35 per 1000 | 18 per 1000 (3 to 100) | RR 0.5 (0.09 to 2.84) | 232 (2 studies) | ⊕⊝⊝⊝ very lowd,e,f | |
| Time to secure airway | The mean time to secure airway in the control groups was 20 seconds | The mean time to secure airway in the intervention groups was 5.9 higher (3 to 8.8 higher) | 70 (1 study) | ⊕⊕⊝⊝ lowb,d | ||
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: Confidence interval; RR: Risk ratio. | ||||||
| GRADE Working Group grades of evidence: High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate. | ||||||
aSubstantial differences between study populations. Heterogeneity (I2 = 71%). bBased on one study only. cUnclear clinical importance of this difference in oxygenation. dImpossible for intubator/assessor to be blinded to airway device used. eBased on 5 events only. fConfidence interval crosses no effect and is consistent with increased and decreased risk.