Short-term effects of neuromuscular blockade on global and regional lung mechanics, oxygenation and ventilation in pediatric acute hypoxemic respiratory failure

Abstract

BackgroundNeuromuscular blockade (NMB) has been shown to improve outcome in acute respiratory distress syndrome (ARDS) in adults, challenging maintaining spontaneous breathing when there is severe lung injury. We tested in a prospective physiological study the hypothesis that continuous administration of NMB agents in mechanically ventilated children with severe acute hypoxemic respiratory failure (AHRF) improves the oxygenation index without a redistribution of tidal volume V T toward non-dependent lung zones.MethodsOxygenation index, PaO2/FiO2 ratio, lung mechanics (plateau pressure, mean airway pressure, respiratory system compliance and resistance), hemodynamics (heart rate, central venous and arterial blood pressures), oxygenation [oxygenation index (OI), PaO2/FiO2 and SpO2/FiO2], ventilation (physiological dead space-to-V T ratio) and electrical impedance tomography measured changes in end-expiratory lung volume (EELV), and V T distribution was measured before and 15 min after the start of continuous infusion of rocuronium 1 mg/kg. Patients were ventilated in a time-cycled, pressure-limited mode with pre-set V T. All ventilator settings were not changed during the study.ResultsTwenty-two patients were studied (N = 18 met the criteria for pediatric ARDS). Median age (25–75 interquartile range) was 15 (7.8–77.5) weeks. Pulmonary pathology was present in 77.3%. The median lung injury score was 9 (8–10). The overall median CoV and regional lung filling characteristics were not affected by NMB, indicating no ventilation shift toward the non-dependent lung zones. Regional analysis showed a homogeneous time course of lung inflation during inspiration, indicating no tendency to atelectasis after the introduction of NMB. NMB decreased the mean airway pressure (p = 0.039) and OI (p = 0.039) in all patients. There were no significant changes in lung mechanics, hemodynamics and EELV. Subgroup analysis showed that OI decreased (p = 0.01) and PaO2/FiO2 increased (p = 0.02) in patients with moderate or severe PARDS.ConclusionsNMB resulted in an improved oxygenation index in pediatric patients with AHRF. Distribution of V T and regional lung filling characteristics were not affected.

Surviving sepsis campaign international guidelines for the management of septic shock and sepsis-associated organ dysfunction in children

“…After adjustment for baseline P/F, plateau pressure, and the Simplified Acute Physiology Score, the cisatracurium group had a hazard ratio for death at 90 days of 0.68 (95% CI, 0.48-0.98) compared with the placebo group. Early use of NMBAs was also associated with decreased organ system dysfunction, less air leak, and a decreased pro-inflammatory response [308]. These findings remained consistent when combined with earlier smaller studies from the same group of investigators in a meta-analysis.…”

The Current State of Pediatric Acute Respiratory Distress Syndrome

“…Valentine et al, 35 Gainnier et al, 57 Forel et al, 58 Papazian et al, 59 Murray et al, 60 Wilsterman et al 62 (continued) recommendations, along with those for adjunctive therapies covered in the following section, are summarized in Table 2.…”

“…A prospective physiologic study by Wilsterman et al showed improved OI in pediatric patients with acute hypoxemic respiratory failure who received continuous NMB during mechanical ventilation. 62 Based largely on the available adult data, PALICC recommends considering NMB in children with PARDS if sedation alone is inadequate to achieve effective mechanical ventilation, targeting the minimal effective dose. 35…”

A case series of children with adenovirus pneumonia: three-year experiences in a tertiary PICU

“…Intravenous neuromuscular blockade was started if the peak inspiratory pressures approximated 28-30 cmH2O, and the patient was hypoxemic and continued to show excessive work of breathing despite adequate sedation [23] . .08] days, p = 0.348).…”