Summary of findings 2. Nebulised magnesium sulfate + standard care compared to placebo + standard care for acute exacerbations of chronic obstructive pulmonary disease.
| Nebulised magnesium sulfate + standard care compared to placebo + standard care for acute exacerbations of chronic obstructive pulmonary disease | ||||||
| Patient or population: acute exacerbations of chronic obstructive pulmonary disease Setting: emergency department Intervention: nebulised magnesium sulfate + standard care Comparison: placebo + standard care | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | No of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Risk with placebo | Risk with nebulised magnesium sulfate | |||||
| Proportion of people with hospital admissions (from the emergency room) | 918 per 1000 | 896 per 1000 (702 to 969) | OR 0.77 (0.21 to 2.82) | 109 (1 RCT) | ⊕⊝⊝⊝ VERY LOW a,c | |
| Proportion of people requiring ICU admission | 109 per 1000 | 45 per 1000 (18 to 109) | OR 0.39 (0.15 to 1.00) | 281 (2 RCTs) | ⊕⊝⊝⊝ VERY LOWd,e | |
| Proportion of people requiring ventilatory support (NIV or assisted ventilation) | 12 per 1000 | 4 per 1000 (0 to 88) | OR 0.33 (0.01 to 8.2) | 172 (1 RCT) | ⊕⊝⊝⊝ VERY LOW c,e | |
| Proportion of people with serious adverse events | No trial assessed this outcome. | |||||
| Length of hospital stay | The mean length of hospital stay was 10.2 days | MD 0.8 lower (4.63 lower to 3.03 higher) | ‐ | 20 (1 RCT) | ⊕⊝⊝⊝ VERY LOW a,c | |
| Change in oxygen saturation (SaO2) | The mean change in SaO2 was 4% | MD 1.1% lower (4.6 lower to 2.4 higher) | ‐ | 20 (1 RCT) | ⊕⊝⊝⊝ VERY LOW a,c | |
| Change in dyspnoea score | The mean dyspnoea score was 9.4 | MD 14.37 lower (26 lower to 2.74 lower) | ‐ | 20 (1 RCT) | ⊕⊝⊝⊝ VERY LOWb,d | VAS dyspnoea score was used. The higher the score, the greater the severity of dyspnoea. |
| Lung function: FEV1 at 60 min | The mean FEV1 at 60 min was 0.81 L | MD 0.05 L lower (0.17 lower to 0.07 higher) | ‐ | 109 (1 RCT) | ⊕⊝⊝⊝ VERY LOW a,c | |
| *The risk in the intervention group (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; FEV1: forced expiratory volume in 1 second; ICU: intensive care unit ; RCT: randomised controlled trial; SaO2: arterial oxygen saturation; OR: odds ratio; MD: mean difference; VAS: visual analogue scale | ||||||
| GRADE Working Group grades of evidence High certainty: We are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: We are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: Our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: We have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect. | ||||||
aDowngraded one level for study limitations (risk of selection and reporting bias) bDowngraded two levels for study limitations (risk of selection, reporting bias and very small participant numbers) cDowngraded two levels for very serious imprecision (few events and CI includes both appreciable benefit and harm) dDowngraded one level for serious imprecision (few events or CI includes non‐appreciable benefit and potential harm) eDowngraded two levels for study limitations (single blinded study with high risk of performance bias)