Summary of findings
| Outcomes | Study type | Number of studies (participants) | Values for clinical parameters in deep sedation groups for included studies (mean (range) of mean value reported in each study)* | Effect estimate and 95% CI (risk ratio for events†; mean difference for duration‡) | I2 | Grade rating |
| Primary outcomes | ||||||
| Mortality | ||||||
| ICU mortality (%) | RCT | 4 (725) | 28.8 (14.1–40.0) | 0.82 (0.58 to 1.17)† | 30% | Moderate |
| Cohort | 3 (2474) | 22.6 (2.2–38.9) | 0.50 (0.13 to 1.86)† | 97% | Very low | |
| Physiological outcomes | ||||||
| Duration of mechanical ventilation (days) | RCT | 2 (165) | 6.6 (5.5–7.7) | −1.44 (−3.79 to 0.91)3 | 20% | Moderate |
| Cohort | 8 (3304) | 7.1 (1.2–10.7) | −1.52 (−2.71 to −0.34)‡ | 87% | Very low | |
| Secondary outcomes | ||||||
| Mortality | ||||||
| Hospital mortality (%) | RCT | 5 (762) | 29.8 (12.5–46.6) | 0.93 (0.75 to 1.15)† | 0% | Moderate |
| Cohort | 5 (4636) | 29.2 (13.7–44.7) | 0.73 (0.41 to 1.30)† | 96% | Very low | |
| Physiological outcomes | ||||||
| Time to extubation (days) | RCT | 1 (423) | 8.0 (8.0–8.0) | −0.67 (−1.95 to 0.61)‡ | 0% | Moderate |
| Cohort | 2 (2132) | 5.6 (3.7–7.4) | −3.77 (−5.49 to −2.06)‡ | 98% | Very low | |
| Ventilator free days to day 28 (days) | RCT | 4 (910) | 15.3 (9.6–20.1) | 2.62 (−0.09 to 5.34)‡ | 31% | Moderate |
| Cohort | 2 (431) | 17.0 (10.3–23.6) | 0.65 (−0.65 to 1.95)* | 0% | Low | |
| Delirium (%) | RCT | 4 (556) | 30.1 (0–52.8) | 1.04 (0.88 to 1.23)† | 0% | Moderate |
| Cohort | 4 (3953) | 37.2 (10.7–55.3) | 1.01 (0.63 to 1.62)† | 95% | Very low | |
| Resource use | ||||||
| ICU length of stay (days) | RCT | 6 (1462) | 14.8 (6.3–28.0) | 0.28 (−1.46 to 2.02)‡ | 32% | Moderate |
| Cohort | 8 (4537) | 11.9 (3.7–23.7) | −4.30 (−7.39 to −1.21)‡ | 97% | Very low | |
| Hospital length of stay (days) | RCT | 5 (762) | 27.5 (16.6–58.6) | −0.69 (−6.96 to 5.58)‡ | 80% | Very low |
| Cohort | 6 (4917) | 19.9 (12.3–30.7) | −4.21 (−7.22 to −1.19)‡ | 88% | Very low | |
| Tracheostomy (%) | RCT | 4 (725) | 15.4 (3.3–29.3) | 1.07 (0.81 to 1.43)† | 0% | Moderate |
| Cohort | 2 (431) | 12.3 (7.7–16.9) | 0.59 (0.31 to 1.12)† | 0% | Very low | |
| Adverse events | ||||||
| Self-extubation (%) | RCT | 2 (189) | 3.2 (3.1–3.3) | 1.31 (0.30 to 5.82)† | 0% | Moderate |
| Cohort | 3 (854) | 6.4 (3.1–9.0) | 1.32 (0.84 to 2.09)† | 0% | Low | |
| Re-intubation (%) | RCT | 5 (1348) | 7.2 (1.6–13.3) | 1.45 (0.78 to 2.71)†2 | 30% | Low |
| Cohort | 2 (362) | 4.2 (1.5–6.9) | 1.07 (0.43 to 2.65)†2 | 0% | Very low | |
| VAP (%) | RCT | 1 (113) | 12.1 (12.1–12.1) | 0.90 (0.32 to 2.52)†2 | 0% | Low |
| Cohort | 2 (1906) | 10.8 (6.5–15.0) | 0.56 (0.33 to 0.96)†2 | 51% | Very low | |
Grade assessment: RCTs started at high quality; cohort studies started at low quality (due to risk of bias); reasons for downgrade included risk of bias (RCTs), imprecision, inconsistency, indirectness.
*Values for clinical parameters in study populations in deep sedation groups for included studies (mean (range) of mean deep sedation group value reported in each study.
†Risk ratio for events.
‡Mean difference for duration.
ICU, intensive care unit; RCT, randomised controlled trial; VAP, ventilator-associated pneumonia.