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.

Utilizing a Collaborative Learning Model to Promote Early Extubation Following Infant Heart Surgery. (Colman)

Mahle WT, et al. Utilizing a Collaborative Learning Model to Promote Early Extubation Following Infant Heart Surgery. Pediatr Crit Care Med. 2016 Aug 10. [Epub ahead of print]

OBJECTIVE: To determine whether a collaborative learning strategy-derived clinical practice guideline can reduce the duration of endotracheal intubation following infant heart surgery.

DESIGN: Prospective and retrospective data collected from the Pediatric Heart Network in the 12 months pre- and post-clinical practice guideline implementation at the four sites participating in the collaborative (active sites) compared with data from five Pediatric Heart Network centers not participating in collaborative learning (control sites).

SETTING: Ten children’s hospitals.

PATIENTS: Data were collected for infants following two-index operations: 1) repair of isolated coarctation of the aorta (birth to 365 d) and 2) repair of tetralogy of Fallot (29-365 d). There were 240 subjects eligible for the clinical practice guideline at active sites and 259 subjects at control sites.

INTERVENTIONS: Development and application of early extubation clinical practice guideline.

MEASUREMENTS AND MAIN RESULTS: After clinical practice guideline implementation, the rate of early extubation at active sites increased significantly from 11.7% to 66.9% (p < 0.001) with no increase in reintubation rate. The median duration of postoperative intubation among active sites decreased from 21.2 to 4.5 hours (p < 0.001). No statistically significant change in early extubation rates was found in the control sites 11.7% to 13.7% (p = 0.63). At active sites, clinical practice guideline implementation had no statistically significant impact on median ICU length of stay (71.9 hr pre- vs 69.2 hr postimplementation; p = 0.29) for the entire cohort. There was a trend toward shorter ICU length of stay in the tetralogy of Fallot subgroup (71.6 hr pre- vs 54.2 hr postimplementation, p = 0.068).

CONCLUSIONS: A collaborative learning strategy designed clinical practice guideline significantly increased the rate of early extubation with no change in the rate of reintubation. The early extubation clinical practice guideline did not significantly change postoperative ICU length of stay.

Poor Adherence to Lung-Protective Mechanical Ventilation in Pediatric Acute Respiratory Distress Syndrome. (Colman)

Ward SL, et al. Poor Adherence to Lung-Protective Mechanical Ventilation in Pediatric Acute Respiratory Distress Syndrome. Pediatr Crit Care Med. 2016 Aug 2. [Epub ahead of print]

OBJECTIVES: To determine the frequency of low-tidal volume ventilation in pediatric acute respiratory distress syndrome and assess if any demographic or clinical factors improve low-tidal volume ventilation adherence.

DESIGN: Descriptive post hoc analysis of four multicenter pediatric acute respiratory distress syndrome studies.

SETTING: Twenty-six academic PICU.

PATIENTS: Three hundred fifteen pediatric acute respiratory distress syndrome patients.

MEASUREMENTS AND MAIN RESULTS: All patients who received conventional mechanical ventilation at hours 0 and 24 of pediatric acute respiratory distress syndrome who had data to calculate ideal body weight were included. Two cutoff points for low-tidal volume ventilation were assessed: less than or equal to 6.5 mL/kg of ideal body weight and less than or equal to 8 mL/kg of ideal body weight. Of 555 patients, we excluded 240 for other respiratory support modes or missing data. The remaining 315 patients had a median PaO2-to-FIO2 ratio of 140 (interquartile range, 90-201), and there were no differences in demographics between those who did and did not receive low-tidal volume ventilation. With tidal volume cutoff of less than or equal to 6.5 mL/kg of ideal body weight, the adherence rate was 32% at hour 0 and 33% at hour 24. A low-tidal volume ventilation cutoff of tidal volume less than or equal to 8 mL/kg of ideal body weight resulted in an adherence rate of 58% at hour 0 and 60% at hour 24. Low-tidal volume ventilation use was no different by severity of pediatric acute respiratory distress syndrome nor did adherence improve over time. At hour 0, overweight children were less likely to receive low-tidal volume ventilation less than or equal to 6.5 mL/kg ideal body weight (11% overweight vs 38% nonoverweight; p = 0.02); no difference was noted by hour 24. Furthermore, in the overweight group, using admission weight instead of ideal body weight resulted in misclassification of up to 14% of patients as receiving low-tidal volume ventilation when they actually were not.

CONCLUSIONS: Low-tidal volume ventilation is underused in the first 24 hours of pediatric acute respiratory distress syndrome. Age, Pediatric Risk of Mortality-III, and pediatric acute respiratory distress syndrome severity were not associated with improved low-tidal volume ventilation adherence nor did adherence improve over time. Overweight children were less likely to receive low-tidal volume ventilation strategies in the first day of illness.

Nutritional Status Based on Body Mass Index Is Associated With Morbidity and Mortality in Mechanically Ventilated Critically Ill Children in the PICU. (Emrath)

Bechard LJ, et al. Nutritional Status Based on Body Mass Index Is Associated With Morbidity and Mortality in Mechanically Ventilated Critically Ill Children in the PICU. Crit Care Med. 2016 Aug;44(8):1530-7.

OBJECTIVE: To determine the influence of admission anthropometry on clinical outcomes in mechanically ventilated children in the PICU.

DESIGN: Data from two multicenter cohort studies were compiled to examine the unique contribution of nutritional status, defined by body mass index z score, to 60-day mortality, hospital-acquired infections, length of hospital stay, and ventilator-free days, using multivariate analysis.

SETTING: Ninety PICUs from 16 countries with eight or more beds.

PATIENTS: Children aged 1 month to 18 years, admitted to each participating PICU and requiring mechanical ventilation for more than 48 hours.

MEASUREMENTS AND MAIN RESULTS: Data from 1,622 eligible patients, 54.8% men and mean (SD) age 4.5 years (5.1), were analyzed. Subjects were classified as underweight (17.9%), normal weight (54.2%), overweight (14.5%), and obese (13.4%) based on body mass index z score at admission. After adjusting for severity of illness and site, the odds of 60-day mortality were higher in underweight (odds ratio, 1.53; p < 0.001) children. The odds of hospital-acquired infections were higher in underweight (odds ratio, 1.88; p = 0.008) and obese (odds ratio, 1.64; p < 0.001) children. Hazard ratios for hospital discharge were lower among underweight (hazard ratio, 0.71; p < 0.001) and obese (hazard ratio, 0.82; p = 0.04) children. Underweight was associated with 1.3 (p = 0.001) and 1.6 (p < 0.001) fewer ventilator-free days than normal weight and overweight, respectively.

CONCLUSIONS: Malnutrition is prevalent in mechanically ventilated children on admission to PICUs worldwide. Classification as underweight or obese was associated with higher risk of hospital-acquired infections and lower likelihood of hospital discharge. Underweight children had a higher risk of mortality and fewer ventilator-free days.