Summary of findings 2. HFNC compared to NIPPV or NIV for respiratory support in adult intensive care patients.
| High‐flow nasal cannulae compared to NIPPV or NIV for respiratory support in adult intensive care patients | ||||||
| Population: adults in the ICU, requiring respiratory support Setting: ICUs. In this review, these ICUs were in: Belgium, China, France, Saudi Arabia, and Spain Intervention: oxygen delivered via HFNC, initiated after extubation from invasive mechanical ventilation or without prior use of invasive mechanical ventilation Comparison: oxygen delivered via NIV or NIPPV (using BiPAP) | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | Number of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Risk with NIPPV or NIV | Risk with HFNC | |||||
|
Treatment failure (escalation of respiratory therapy to NIV, NIPPV or invasive ventilation) Measured up to 28 days |
Study population | RR 0.98 (0.78 to 1.22) | 1758 (5 studies) | ⊕⊕⊝⊝ Lowa |
We conducted subgroup analysis and found no evidence of a difference in treatment failure when used post‐extubation (RR 1.12, 95% CI 0.89 to 1.41; 3 studies, 1472 participants) and without prior use of mechanical ventilation (RR 0.77, 95% CI 0.58 to 1.03; 2 studies, 286 participants) | |
| 202 per 1000 | 198 per 1000 (158 to 247) | |||||
|
In‐hospital mortality (up to 90 days; included studies reported in‐hospital mortality, and mortality up to 28 days and up to ICU discharge) |
Study population | RR 0.92 (0.64 to 1.31) | 1758 (5 studies) | ⊕⊕⊝⊝ Lowa |
‐ | |
| 136 per 1000 | 126 per 1000 (87 to 179) | |||||
|
Adverse events Respiratory infection (pneumonia) |
Study population for pneumonia | RR 0.51 (0.17 to 1.52) | 1750 (3 studies) | ⊕⊝⊝⊝ Verylowb |
‐ | |
| 159 per 1000 | 81 per 1000 (27 to 241) | |||||
| Barotrauma (pneumothorax) | Study population for barotrauma | RR 1.15 (0.42 to 3.14) | 830 (1 study) | ⊕⊝⊝⊝ Lowc |
‐ | |
| 17 per 1000 | 19 per 1000 (7 to 53) | |||||
| Nasal mucosa or skin trauma | Study population for nasal mucosa or skin trauma | ‐ | ‐ | ‐ | No studies reported this outcome | |
| ‐ | ‐ | |||||
| Length of ICU stay | 9.9 days | MD 0.72 days lower (2.85 days lower to 1.42 days higher) | ‐ | 246 (2 studies) | ⊕⊕⊝⊝ Lowd |
In addition, 2 studies reported median lengths of ICU stay which we did not combine in analysis; these studies reported little or no difference in median lengths of ICU stay |
| Respiratory effects: PaO2/FiO2 ratio up to 24 hours after initiation of therapy | 228.9 mmHg | MD 58.1 mmHg lower (71.68 mmHg lower to 44.51 mmHg lower) | ‐ | 1086 (3 studies) | ⊕⊕⊝⊝ Lowe |
‐ |
|
Comfort (short‐term effect) Measured up to 24 hours, scales were standardized to allow comparison; higher numbers indicate more comfort |
6.06 | MD 1.33 higher (0.74 higher to 1.92 higher) | ‐ | 258 (2 studies) | ⊕⊝⊝⊝ Verylowf |
In addition, 1 study reported improved comfort with HFNC (RR 1.30, 95% CI 1.10 to 1.53; 1 study, 168 participants), and 1 study (830 participants) reported little or no difference between types of respiratory support, with comfort rated as 'poor', 'acceptable' or 'good'. |
|
Comfort (long‐term effect) Measured at more than 24 hours |
‐ | ‐ | ‐ | ‐ | ⊕⊝⊝⊝ Verylowg |
1 study (304 participants) reported little or no difference between types of respiratory support, with comfort rated as 'poor', 'acceptable' or 'good'. |
| *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). We present baseline risk values for NIPPV/NIV as the weighted mean values reported in included studies for each outcome. For comfort, these values are a score from 0 (least comfort) to 10 (most comfort). CI: Confidence interval; HFNC: high‐flow nasal cannulae; ICU: intensive care unit; MD: mean difference; NIPPV: non‐invasive positive pressure ventilation; NIV: non‐invasive ventilation; PaO2/FiO2: ratio of partial pressure of arterial oxygen to the fraction of inspired oxygen; RR: risk ratio; SMD: standardized mean difference | ||||||
| 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 | ||||||
aWe downgraded by two levels: we downgraded by one level for inconsistency because we noted some variation in the results which we could not explain. We also downgraded by one level for study limitations because we judged one study to have a high risk of bias owing to the use of alternative treatment between intermittent HFNC use. bWe downgraded by three levels: we downgraded by two levels for inconsistency because we noted variation in the results of individual studies and a substantial level of statistical heterogeneity, and by one level for study limitations because we judged one study to have a high risk of bias owing to the use of alternative treatment between intermittent HFNC use. cWe downgraded by two levels for imprecision because only one study contributed evidence to this outcome and we noted a wide CI in the effect. dWe downgraded by two levels: we downgraded by one level for inconsistency because we noted a wide variation in length of stay within studies, and by one level for study limitations because we judged one study to have a high risk of bias owing to the use of alternative treatment between intermittent HFNC use. eWe downgraded by two levels: we downgraded by one level for inconsistency because one study had a particularly wide CI and we noted differences in PaO2/FiO2 between studies which could be explained by the different reasons for needing respiratory support between studies. We also downgraded by one level for study limitations because we judged one study to have a high risk of bias owing to the use of alternative treatment between intermittent HFNC use. fWe downgraded by three levels: we downgraded by two levels for inconsistency because we noted some variation between study results, and by one level for study limitations because we judged one study to have a high risk of bias owing to the use of alternative treatment between intermittent HFNC use. gWe downgraded by three levels: we downgraded by two levels for imprecision because only one study contributed evidence for this outcome, and one level for study limitations because we noted a high rate of attrition for comfort scores measured at day 3.