Airway obstruction and atelectasis attributable to mucus plugging is a frequent complication in ventilated pediatric intensive care (PICU) patients due to a combination of thick viscous secretions and the small caliber of the airway. The abnormal viscoelastic properties of the secretions are due to the presence of highly polymerized polyionic DNA from the nuclei of degenerating polymorphonuclear leukocytes.Treatment of the atelectasis by conventional methods often fails and flexible bronchoscopy is technically difficult in this population. Recombinant human DNase (rhDNase, Pulmozyme) has been shown to reduce the viscosity of purulent bronchial secretion by fragmenting extracellular DNA. We present our experience with rhDNase in a ventilated pediatric population.
Retrospective chart review of all intubated and ventilated patients in the PICU treated with rhDNase for atelectasis (N=6). Conventional methods of treating atelectasis failed or were contra-indicated in these patients. All had atelectasis for over 48 hours. 2.5mg of rhDNase was instilled through the endotracheal tube via an in-line suction catheter every 12 hrs till resolution of atelectasis. Patients were positioned with the atelectatic side down. Outcome was monitored with serial chest radiographs.
All six patients who met the inclusion criteria suffered varying degrees of atelectasis while on mechanical ventilation. All had complete resolution of atelectasis, documented by chest radiograph, with one to four doses of rhDNase. Table IRhDNase Patient CharacteristicsPatientAgeWeightDiagnosisDoses of rhDNaseAA4 mo3.8kgRSV(-) Bronchiolitis2TC17 mo12.5kgRSV (+) Bronchiolitis4DB2 yrs12.7kgAbdominal Trauma1CL3 yrs15kgHead Trauma4TP17 yrs32kgRetts Syndrome/Aspiration1CW2 yrs11.3kgCricoid Split/Subglottic Stenosis2and
RhDNase is used in Europe and Canada for the treatment of atelectasis; there is consensus over the efficacy of a standatd 2.5mg dose. However, the optimal mode of administration is still debated. In our case series we demonstrate the effective use of instilled rather than nebulized rhDNase to treat atelectasis when administered as 2.5mg diluted in 5cc of normal saline, followed with manual breaths. The patient is positioned with the atelectatic side in the dependent position to improve delivery of the rhDNase.CLINICAL IMPLICATION: A therapeutic trial of rhDNase should be considered in the treatment of atelectasis in ventilated children before invasive bronchoscopy.
S.S. Da-Silva, None.