Lung Rest During Extracorporeal Membrane Oxygenation for Neonatal Respiratory Failure-Practice Variations and Outcomes. (Duke)

Alapati D, et al. Lung Rest During Extracorporeal Membrane Oxygenation for Neonatal Respiratory Failure-Practice Variations and Outcomes. Pediatr Crit Care Med. 2017 Jul;18(7):667-674.

OBJECTIVE: Describe practice variations in ventilator strategies used for lung rest during extracorporeal membrane oxygenation for respiratory failure in neonates, and assess the potential impact of various lung rest strategies on the duration of extracorporeal membrane oxygenation and the duration of mechanical ventilation after decannulation.

DATA SOURCES: Retrospective cohort analysis from the Extracorporeal Life Support Organization registry database during the years 2008-2013.

STUDY SELECTION: All extracorporeal membrane oxygenation runs for infants less than or equal to 30 days of life for pulmonary reasons were included.

DATA EXTRACTION: Ventilator type and ventilator settings used for lung rest at 24 hours after extracorporeal membrane oxygenation initiation were obtained.

DATA SYNTHESIS: A total of 3,040 cases met inclusion criteria. Conventional mechanical ventilation was used for lung rest in 88% of cases and high frequency ventilation was used in 12%. In the conventional mechanical ventilation group, 32% used positive end-expiratory pressure strategy of 4-6 cm H2O (low), 22% used 7-9 cm H2O (mid), and 43% used 10-12 cm H2O (high). High frequency ventilation was associated with an increased mean (SEM) hours of extracorporeal membrane oxygenation (150.2 [0.05] vs 125 [0.02]; p < 0.001) and an increased mean (SEM) hours of mechanical ventilation after decannulation (135 [0.09] vs 100.2 [0.03]; p = 0.002), compared with conventional mechanical ventilation among survivors. Within the conventional mechanical ventilation group, use of higher positive end-expiratory pressure was associated with a decreased mean (SEM) hours of extracorporeal membrane oxygenation (high vs low: 136 [1.06] vs 156 [1.06], p = 0.001; mid vs low: 141 [1.06] vs 156 [1.06]; p = 0.04) but increased duration of mechanical ventilation after decannulation in the high positive end-expiratory pressure group compared with low positive end-expiratory pressure (p = 0.04) among survivors.

CONCLUSIONS: Wide practice variation exists with regard to ventilator settings used for lung rest during neonatal respiratory extracorporeal membrane oxygenation. Use of high frequency ventilation when compared with conventional mechanical ventilation and use of low positive end-expiratory pressure strategy when compared with mid positive end-expiratory pressure and high positive end-expiratory pressure strategy is associated with longer duration of extracorporeal membrane oxygenation. Further research to provide evidence to drive optimization of pulmonary management during neonatal respiratory extracorporeal membrane oxygenation is warranted.

Partial Neuromuscular Blockade during Partial Ventilatory Support in Sedated Patients with High Tidal Volumes. (Stulce)

Doorduin J, Nollet JL, Roesthuis LH, et al. Partial Neuromuscular Blockade during Partial Ventilatory Support in Sedated Patients with High Tidal Volumes. Am J Respir Crit Care Med. 2017 Apr 15;195(8):1033-1042.

RATIONALE: Controlled mechanical ventilation is used to deliver lung-protective ventilation in patients with acute respiratory distress syndrome. Despite recognized benefits, such as preserved diaphragm activity, partial support ventilation modes may be incompatible with lung-protective ventilation due to high Vt and high transpulmonary pressure. As an alternative to high-dose sedatives and controlled mechanical ventilation, pharmacologically induced neuromechanical uncoupling of the diaphragm should facilitate lung-protective ventilation under partial support modes.

OBJECTIVES: To investigate whether partial neuromuscular blockade can facilitate lung-protective ventilation while maintaining diaphragm activity under partial ventilatory support.

METHODS: In a proof-of-concept study, we enrolled 10 patients with lung injury and a Vt greater than 8 ml/kg under pressure support ventilation (PSV) and under sedation. After baseline measurements, rocuronium administration was titrated to a target Vt of 6 ml/kg during neurally adjusted ventilatory assist (NAVA). Thereafter, patients were ventilated in PSV and NAVA under continuous rocuronium infusion for 2 hours. Respiratory parameters, hemodynamic parameters, and blood gas values were measured.

MEASUREMENTS AND MAIN RESULTS: Rocuronium titration resulted in significant declines of Vt (mean ± SEM, 9.3 ± 0.6 to 5.6 ± 0.2 ml/kg; P < 0.0001), transpulmonary pressure (26.7 ± 2.5 to 10.7 ± 1.2 cm H2O; P < 0.0001), and diaphragm electrical activity (17.4 ± 2.3 to 4.5 ± 0.7 μV; P < 0.0001), and could be maintained under continuous rocuronium infusion. During titration, pH decreased (7.42 ± 0.02 to 7.35 ± 0.02; P < 0.0001), and mean arterial blood pressure increased (84 ± 6 to 99 ± 6 mm Hg; P = 0.0004), as did heart rate (83 ± 7 to 93 ± 8 beats/min; P = 0.0004).

CONCLUSIONS: Partial neuromuscular blockade facilitates lung-protective ventilation during partial ventilatory support, while maintaining diaphragm activity, in sedated patients with lung injury.

Improving Hospital Survival and Reducing Brain Dysfunction at Seven California Community Hospital… (Betters)

Barnes-Daly MA, Phillips G, Ely EW. Improving Hospital Survival and Reducing Brain Dysfunction at Seven California Community Hospitals: Implementing PAD Guidelines Via the ABCDEF Bundle in 6,064 Patients. Crit Care Med. 2017 Feb; 45(2):171-178.

OBJECTIVES: To track compliance by an interprofessional team with the Awakening and Breathing Coordination, Choice of drugs, Delirium monitoring and management, Early mobility, and Family engagement (ABCDEF) bundle in implementing the Pain, Agitation, and Delirium guidelines. The aim was to study the association between ABCDEF bundle compliance and outcomes including hospital survival and delirium-free and coma-free days in community hospitals.

DESIGN: A prospective cohort quality improvement initiative involving ICU patients.

SETTING: Seven community hospitals within California’s Sutter Health System.

PATIENTS: Ventilated and nonventilated general medical and surgical ICU patients enrolled between January 1, 2014, and December 31, 2014.

MEASUREMENTS AND MAIN RESULTS: Total and partial bundle compliance were measured daily. Random effects regression was used to determine the association between ABCDEF bundle compliance accounting for total compliance (all or none) or for partial compliance (“dose” or number of bundle elements used) and outcomes of hospital survival and delirium-free and coma-free days, after adjusting for age, severity of illness, and presence of mechanical ventilation. Of 6,064 patients, a total of 586 (9.7%) died before hospital discharge. For every 10% increase in total bundle compliance, patients had a 7% higher odds of hospital survival (odds ratio, 1.07; 95% CI, 1.04-1.11; p < 0.001). Likewise, for every 10% increase in partial bundle compliance, patients had a 15% higher hospital survival (odds ratio, 1.15; 95% CI, 1.09-1.22; p < 0.001). These results were even more striking (12% and 23% higher odds of survival per 10% increase in bundle compliance, respectively, p < 0.001) in a sensitivity analysis removing ICU patients identified as receiving palliative care. Patients experienced more days alive and free of delirium and coma with both total bundle compliance (incident rate ratio, 1.02; 95% CI, 1.01-1.04; p = 0.004) and partial bundle compliance (incident rate ratio, 1.15; 95% CI, 1.09-1.22; p < 0.001).

CONCLUSIONS: The evidence-based ABCDEF bundle was successfully implemented in seven community hospital ICUs using an interprofessional team model to operationalize the Pain, Agitation, and Delirium guidelines. Higher bundle compliance was independently associated with improved survival and more days free of delirium and coma after adjusting for age, severity of illness, and presence of mechanical ventilation.

Early Noninvasive Neurally Adjusted Ventilatory Assist Versus Noninvasive Flow-Triggered Pressure Support Ventilation in Pediatric Acute Respiratory Failure: A Physiologic Randomized Controlled Trial. (Carroll)

Chidini G, et al. Early Noninvasive Neurally Adjusted Ventilatory Assist Versus Noninvasive Flow-Triggered Pressure Support Ventilation in Pediatric Acute Respiratory Failure: A Physiologic Randomized Controlled Trial. Pediatr Crit Care Med. 2016 Nov;17(11):e487-e495.

OBJECTIVE: Neurally adjusted ventilatory assist has been shown to improve patient-ventilator interaction in children with acute respiratory failure. Objective of this study was to compare the effect of noninvasive neurally adjusted ventilatory assist versus noninvasive flow-triggered pressure support on patient-ventilator interaction in children with acute respiratory failure, when delivered as a first-line respiratory support.

DESIGN: Prospective randomized crossover physiologic study.

SETTING: Pediatric six-bed third-level PICU.

PATIENTS: Eighteen children with acute respiratory failure needing noninvasive ventilation were enrolled at PICU admission.

INTERVENTIONS: Enrolled children were allocated to receive two 60-minutes noninvasive flow-triggered pressure support and noninvasive neurally adjusted ventilatory assist trials in a crossover randomized sequence.

MEASUREMENTS AND MAIN RESULTS: Primary endpoint was the asynchrony index. Parameters describing patient-ventilator interaction and gas exchange were also considered as secondary endpoints. Noninvasive neurally adjusted ventilatory assist compared to noninvasive flow-triggered pressure support: 1) reduced asynchrony index (p = 0.001) and the number of asynchronies per minute for each type of asynchrony; 2) it increased the neuroventilatory efficiency index (p = 0.001), suggesting better neuroventilatory coupling; 3) reduced inspiratory and expiratory delay times (p = 0.001) as well as lower peak and mean airway pressure (p = 0.006 and p = 0.038, respectively); 4) lowered oxygenation index (p = 0.043). No adverse event was reported.

CONCLUSIONS: In children with mild early acute respiratory failure, noninvasive neurally adjusted ventilatory assist was feasible and safe. Noninvasive neurally adjusted ventilatory assist compared to noninvasive flow-triggered pressure support improved patient-ventilator interaction.