Effect of High-Flow Nasal Cannula Therapy vs Continuous Positive Airway Pressure Therapy on Liberation From Respiratory Support in Acutely Ill Children Admitted to Pediatric Critical Care Units: A Randomized Clinical Trial.

Importance: The optimal first-line mode of noninvasive respiratory support for acutely ill children is not known. Objective: To evaluate the noninferiority of high-flow nasal cannula therapy (HFNC) as the first-line mode of noninvasive respiratory support for acute illness, compared with continuous positive airway pressure (CPAP), for time to liberation from all forms of respiratory support. Design, Setting, and Participants: Pragmatic, multicenter, randomized noninferiority clinical trial conducted in 24 pediatric critical care units in the United Kingdom among 600 acutely ill children aged 0 to 15 years who were clinically assessed to require noninvasive respiratory support, recruited between August 2019 and November 2021, with last follow-up completed in March 2022. Interventions: Patients were randomized 1:1 to commence either HFNC at a flow rate based on patient weight (n = 301) or CPAP of 7 to 8 cm H2O (n = 299). Main Outcomes and Measures: The primary outcome was time from randomization to liberation from respiratory support, defined as the start of a 48-hour period during which a participant was free from all forms of respiratory support (invasive or noninvasive), assessed against a noninferiority margin of an adjusted hazard ratio of 0.75. Seven secondary outcomes were assessed, including mortality at critical care unit discharge, intubation within 48 hours, and use of sedation. Results: Of the 600 randomized children, consent was not obtained for 5 (HFNC: 1; CPAP: 4) and respiratory support was not started in 22 (HFNC: 5; CPAP: 17); 573 children (HFNC: 295; CPAP: 278) were included in the primary analysis (median age, 9 months; 226 girls [39%]). The median time to liberation in the HFNC group was 52.9 hours (95% CI, 46.0-60.9 hours) vs 47.9 hours (95% CI, 40.5-55.7 hours) in the CPAP group (absolute difference, 5.0 hours [95% CI -10.1 to 17.4 hours]; adjusted hazard ratio 1.03 [1-sided 97.5% CI, 0.86-∞]). This met the criterion for noninferiority. Of the 7 prespecified secondary outcomes, 3 were significantly lower in the HFNC group: use of sedation (27.7% vs 37%; adjusted odds ratio, 0.59 [95% CI, 0.39-0.88]); mean duration of critical care stay (5 days vs 7.4 days; adjusted mean difference, -3 days [95% CI, -5.1 to -1 days]); and mean duration of acute hospital stay (13.8 days vs 19.5 days; adjusted mean difference, -7.6 days [95% CI, -13.2 to -1.9 days]). The most common adverse event was nasal trauma (HFNC: 6/295 [2.0%]; CPAP: 18/278 [6.5%]). Conclusions and Relevance: Among acutely ill children clinically assessed to require noninvasive respiratory support in a pediatric critical care unit, HFNC compared with CPAP met the criterion for noninferiority for time to liberation from respiratory support. Trial Registration: ISRCTN.org Identifier: ISRCTN60048867.

Effect of High-Flow Nasal Cannula Therapy vs Continuous Positive Airway Pressure Following Extubation on Liberation From Respiratory Support in Critically Ill Children: A Randomized Clinical Trial.

Importance: The optimal first-line mode of noninvasive respiratory support following extubation of critically ill children is not known. Objective: To evaluate the noninferiority of high-flow nasal cannula (HFNC) therapy as the first-line mode of noninvasive respiratory support following extubation, compared with continuous positive airway pressure (CPAP), on time to liberation from respiratory support. Design, Setting, and Participants: This was a pragmatic, multicenter, randomized, noninferiority trial conducted at 22 pediatric intensive care units in the United Kingdom. Six hundred children aged 0 to 15 years clinically assessed to require noninvasive respiratory support within 72 hours of extubation were recruited between August 8, 2019, and May 18, 2020, with last follow-up completed on November 22, 2020. Interventions: Patients were randomized 1:1 to start either HFNC at a flow rate based on patient weight (n = 299) or CPAP of 7 to 8 cm H2O (n = 301). Main Outcomes and Measures: The primary outcome was time from randomization to liberation from respiratory support, defined as the start of a 48-hour period during which the child was free from all forms of respiratory support (invasive or noninvasive), assessed against a noninferiority margin of an adjusted hazard ratio (HR) of 0.75. There were 6 secondary outcomes, including mortality at day 180 and reintubation within 48 hours. Results: Of the 600 children who were randomized, 553 children (HFNC, 281; CPAP, 272) were included in the primary analysis (median age, 3 months; 241 girls [44%]). HFNC failed to meet noninferiority, with a median time to liberation of 50.5 hours (95% CI, 43.0-67.9) vs 42.9 hours (95% CI, 30.5-48.2) for CPAP (adjusted HR, 0.83; 1-sided 97.5% CI, 0.70-∞). Similar results were seen across prespecified subgroups. Of the 6 prespecified secondary outcomes, 5 showed no significant difference, including the rate of reintubation within 48 hours (13.3% for HFNC vs 11.5 % for CPAP). Mortality at day 180 was significantly higher for HFNC (5.6% vs 2.4% for CPAP; adjusted odds ratio, 3.07 [95% CI, 1.1-8.8]). The most common adverse events were abdominal distension (HFNC: 8/281 [2.8%] vs CPAP: 7/272 [2.6%]) and nasal/facial trauma (HFNC: 14/281 [5.0%] vs CPAP: 15/272 [5.5%]). Conclusions and Relevance: Among critically ill children requiring noninvasive respiratory support following extubation, HFNC compared with CPAP following extubation failed to meet the criterion for noninferiority for time to liberation from respiratory support. Trial Registration: isrctn.org Identifier: ISRCTN60048867.

Effect of Reduced Exposure to Vasopressors on 90-Day Mortality in Older Critically Ill Patients With Vasodilatory Hypotension: A Randomized Clinical Trial.

Importance: Vasopressors are commonly administered to intensive care unit (ICU) patients to raise blood pressure. Balancing risks and benefits of vasopressors is a challenge, particularly in older patients. Objective: To determine whether reducing exposure to vasopressors through permissive hypotension (mean arterial pressure [MAP] target, 60-65 mm Hg) reduces mortality at 90 days in ICU patients aged 65 years or older with vasodilatory hypotension. Design, Setting, and Participants: A multicenter, pragmatic, randomized clinical trial was conducted in 65 ICUs in the United Kingdom and included 2600 randomized patients aged 65 years or older with vasodilatory hypotension (assessed by treating clinician). The study was conducted from July 2017 to March 2019, and follow-up was completed in August 2019. Interventions: Patients were randomized 1:1 to vasopressors guided either by MAP target (60-65 mm Hg, permissive hypotension) (n = 1291) or according to usual care (at the discretion of treating clinicians) (n = 1307). Main Outcome and Measures: The primary clinical outcome was all-cause mortality at 90 days. Results: Of 2600 randomized patients, after removal of those who declined or had withdrawn consent, 2463 (95%) were included in the analysis of the primary outcome (mean [SD] age 75 years [7 years]; 1387 [57%] men). Patients randomized to the permissive hypotension group had lower exposure to vasopressors compared with those in the usual care group (median duration 33 hours vs 38 hours; difference in medians, -5.0; 95% CI, -7.8 to -2.2 hours; total dose in norepinephrine equivalents median, 17.7 mg vs 26.4 mg; difference in medians, -8.7 mg; 95% CI, -12.8 to -4.6 mg). At 90 days, 500 of 1221 (41.0%) in the permissive hypotension compared with 544 of 1242 (43.8%) in the usual care group had died (absolute risk difference, -2.85%; 95% CI, -6.75 to 1.05; P = .15) (unadjusted relative risk, 0.93; 95% CI, 0.85-1.03). When adjusted for prespecified baseline variables, the odds ratio for 90-day mortality was 0.82 (95% CI, 0.68 to 0.98). Serious adverse events were reported for 79 patients (6.2%) in the permissive care group and 75 patients (5.8%) in the usual care group. The most common serious adverse events were acute renal failure (41 [3.2%] vs 33 [2.5%]) and supraventricular cardiac arrhythmia (12 [0.9%] vs 13 [1.0%]). Conclusions and Relevance: Among patients 65 years or older receiving vasopressors for vasodilatory hypotension, permissive hypotension compared with usual care did not result in a statistically significant reduction in mortality at 90 days. However, the confidence interval around the point estimate for the primary outcome should be considered when interpreting the clinical importance of the study. Trial Registration: isrctn.org Identifier: ISRCTN10580502.

Reduced exposure to vasopressors through permissive hypotension to reduce mortality in critically ill people aged 65 and over: the 65 RCT.

BACKGROUND: Vasopressors are administered to critical care patients to avoid hypotension, which is associated with myocardial injury, kidney injury and death. However, they work by causing vasoconstriction, which may reduce blood flow and cause other adverse effects. A mean arterial pressure target typically guides administration. An individual patient data meta-analysis (Lamontagne F, Day AG, Meade MO, Cook DJ, Guyatt GH, Hylands M, et al. Pooled analysis of higher versus lower blood pressure targets for vasopressor therapy septic and vasodilatory shock. Intensive Care Med 2018;44:12-21) suggested that greater exposure, through higher mean arterial pressure targets, may increase risk of death in older patients. OBJECTIVE: To estimate the clinical effectiveness and cost-effectiveness of reduced vasopressor exposure through permissive hypotension (i.e. a lower mean arterial pressure target of 60-65 mmHg) in older critically ill patients. DESIGN: A pragmatic, randomised clinical trial with integrated economic evaluation. SETTING: Sixty-five NHS adult general critical care units. PARTICIPANTS: Critically ill patients aged ≥ 65 years receiving vasopressors for vasodilatory hypotension. INTERVENTIONS: Intervention - permissive hypotension (i.e. a mean arterial pressure target of 60-65 mmHg). Control (usual care) - a mean arterial pressure target at the treating clinician's discretion. MAIN OUTCOME MEASURES: The primary clinical outcome was 90-day all-cause mortality. The primary cost-effectiveness outcome was 90-day incremental net monetary benefit. Secondary outcomes included receipt and duration of advanced respiratory and renal support, mortality at critical care and acute hospital discharge, and questionnaire assessment of cognitive decline and health-related quality of life at 90 days and 1 year. RESULTS: Of 2600 patients randomised, 2463 (permissive hypotension, n = 1221; usual care, n = 1242) were analysed for the primary clinical outcome. Permissive hypotension resulted in lower exposure to vasopressors than usual care [mean duration 46.0 vs. 55.9 hours, difference -9.9 hours (95% confidence interval -14.3 to -5.5 hours); total noradrenaline-equivalent dose 31.5 mg vs. 44.3 mg, difference -12.8 mg (95% CI -18.0 mg to -17.6 mg)]. By 90 days, 500 (41.0%) patients in the permissive hypotension group and 544 (43.8%) patients in the usual-care group had died (absolute risk difference -2.85%, 95% confidence interval -6.75% to 1.05%; p = 0.154). Adjustment for prespecified baseline variables resulted in an odds ratio for 90-day mortality of 0.82 (95% confidence interval 0.68 to 0.98) favouring permissive hypotension. There were no significant differences in prespecified secondary outcomes or subgroups; however, patients with chronic hypertension showed a mortality difference favourable to permissive hypotension. At 90 days, permissive hypotension showed similar costs to usual care. However, with higher incremental life-years and quality-adjusted life-years in the permissive hypotension group, the incremental net monetary benefit was positive, but with high statistical uncertainty (£378, 95% confidence interval -£1347 to £2103). LIMITATIONS: The intervention was unblinded, with risk of bias minimised through central allocation concealment and a primary outcome not subject to observer bias. The control group event rate was higher than anticipated. CONCLUSIONS: In critically ill patients aged ≥ 65 years receiving vasopressors for vasodilatory hypotension, permissive hypotension did not significantly reduce 90-day mortality compared with usual care. The absolute treatment effect on 90-day mortality, based on 95% confidence intervals, was between a 6.8-percentage reduction and a 1.1-percentage increase in mortality. FUTURE WORK: Future work should (1) update the individual patient data meta-analysis, (2) explore approaches for evaluating heterogeneity of treatment effect and (3) explore 65 trial conduct, including use of deferred consent, to inform future trials. TRIAL REGISTRATION: Current Controlled Trials ISRCTN10580502. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 14. See the NIHR Journals Library website for further project information.

Low blood pressure is common in patients in intensive care. It is associated with a high risk of death. It can be treated with drugs called vasopressors. These drugs raise blood pressure, but also come with risks and side effects. Usually, a blood pressure target is used to guide how much of the drugs to give to patients. Two previous clinical trials suggested that using a lower blood pressure target (and therefore giving less of the drugs) might reduce the number of deaths among older patients. However, although these results were promising, more research was needed to find out if they were correct. The 65 trial was carried out to test if using a lower blood pressure target really did improve outcomes for older patients. The trial also looked at whether or not it would provide value for money for the NHS. A total of 2600 patients aged ≥ 65 years who had low blood pressure in intensive care joined the trial. Half were randomly assigned to the new lower blood pressure target (less drugs). The other half were assigned to usual care (control group). As we had hoped, patients in the low blood pressure target group received less vasopressor drugs than the usual-care group. After 90 days, 41% of patients in the new low blood pressure target group had died, compared with 44% in the usual-care group. Although fewer patients died in the low blood pressure target group, the difference was small and may have occurred by chance. On average, the new target saved a small amount of money for the NHS. Although we could not prove that use of a lower blood pressure target saves lives for older patients in intensive care, our trial suggests that it might. Receiving less vasopressor drugs appeared safe for patients.