Effect of manual hyperinflation with versus without positive end-expiratory pressure on dynamic compliance in pediatric patients following congenital heart surgery: A randomized controlled trial.

BACKGROUND: We aimed to compare the effect of manual hyperinflation with versus without positive end-expiratory pressure (PEEP) on dynamic compliance of the respiratory system in pediatric patients undergoing congenital heart surgery; to assess the safety of the technique in this population. METHODS: This was a randomized controlled trial conducted at the pediatric intensive care unit (PICU) of a tertiary-care hospital. Patients admitted to the PICU following cardiac surgery and receiving postoperative mechanical ventilation were randomized to the experimental or control group. Patients in the experimental group (n = 14) underwent manual hyperinflation with a PEEP valve set at 5 cm H2O, once daily, during the first 48 hours after surgery. Patients allocated to the control group (n = 16) underwent manual hyperinflation without PEEP, at the same time points. Lung mechanics was assessed before (T0) and 5 minutes (T5) after manual hyperinflation. The primary endpoint was dynamic compliance. Secondary outcomes included oxygen saturation index, duration of mechanical ventilation, length of stay, 28-day mortality and safety. RESULTS: Demographic and clinical characteristics were comparable in both groups. There was no significant difference in dynamic compliance between times in each group (Day 1: (mean) 0.78 vs 0.81 and 0.70 vs 0.77; Day 2: 0.85 vs 0.78 and 0.67 vs 0.68 mL/kg/cm H2O, in experimental and control groups, respectively; P > .05). Mean deltas of dynamic compliance were not significantly different between groups. The proportion of patients extubated <72 hours after surgery was similar in experimental and control groups (43% vs 50%, respectively; P = .73). Oxygen saturation index, length of stay, and 28-day mortality were not significantly different between groups. None of the patients had hemodynamic instability. CONCLUSIONS: Manual hyperinflation was safe and well tolerated in pediatric patients following surgery for congenital heart disease. No significant change in dynamic compliance of the respiratory system or in oxygenation was observed with the use of manual hyperinflation with or without PEEP in this population.

Occult risk factor for the development of cerebral edema in children with diabetic ketoacidosis: possible role for stomach emptying.

The incidence of cerebral edema during therapy of diabetic ketoacidosis (DKA) in children remains unacceptably high-this suggests that current treatment may not be ideal and that important risk factors for the development of cerebral edema have not been recognized. We suggest that there are two major sources for an occult generation of osmole-free water in these patients: first, fluid with a low concentration of electrolytes that was retained in the lumen of the stomach when the patient arrived in hospital; second, infusion of glucose in water at a time when this solution can be converted into water with little glucose. In a retrospective chart review of 30 patients who were admitted with a diagnosis of DKA and a blood sugar > 900 mg/dL (50 mmol/L), there were clues to suggest that some of the retained fluid in the stomach was absorbed. To minimize the likelihood of creating a dangerous degree of cerebral edema in patients with DKA, it is important to define the likely composition of fluid retained in the stomach on admission, to look for signs of absorption of some of this fluid during therapy, and to be especially vigilant once fat-derived brain fuels have disappeared, because this is the time when glucose oxidation in the brain should increase markedly, generating osmole-free water.