Resolution of chronic atelectasis in a child with asthma after aerosolized recombinant human DNase

Mucolytics for intubated asthmatic children: a national survey of United kingdom paediatric intensive care consultants

Aim. The extent to which mucolytics are utilised in mechanically ventilated asthmatic children is unknown. We sought to establish current practice in the United Kingdom (UK) including choice of mucolytic, dose, and frequency of utilisation. Methods. A national electronic survey was distributed to UK consultants during April and May 2014. We were able to identify 168 PICU consultants at 25 institutions to whom we were able to electronically distribute a survey, representing an estimated 81% of UK NHS PICU consultants. Results. Replies were received from 87 consultants at 21 institutions (response rate = 52%). Recombinant human DNase (rhDNase) does get administered by 63% of clinicians, with 54% and 19% that administer hypertonic saline or N-acetylcysteine, respectively. Of those that do administer rhDNase the majority (48%) dilute it with 0.9% saline and blindly administer it, whereas 35% administer rhDNase under bronchoscopic guidance and 17% judge the necessity for bronchoscopy according to clinical severity. 25 respondents described 7 different methods to calculate rhDNase dose. A majority (87%) of respondents expressed an interest to consider enrolling patients into an RCT that evaluates rhDNase. Conclusion. Significant variation exists regarding the necessity for mucolytics, choice of agent, optimal route, and dose in intubated asthmatic children.

Dornase Alfa for Non–Cystic Fibrosis Pediatric Pulmonary Atelectasis

Objective: To review the literature evaluating the efficacy of dornase alfa for non–cystic fibrosis pediatric patients with pulmonary atelectasis. Data Sources: Articles were retrieved after a search of MEDLINE/PubMed (1946 to April 2014), and International Pharmaceutical Abstracts (1970-April 2014) was performed using the terms dornase alfa, recombinant human deoxyribonuclease, pulmonary, persistent, and atelectasis. Other relevant articles referenced from the MEDLINE search were also utilized. Study Selection and Data Extraction: Data sources were limited to English language clinical trials and case studies including only children; 8 clinical trials and 12 case reports met the criteria. Data Synthesis: Dornase alfa is used as an off-label treatment option for pulmonary atelectasis because limited treatment modalities exist after conventional therapy has failed. We evaluated 8 clinical trials and 12 case reports involving this pediatric population with varying primary diagnoses. The majority of patients experienced improvement in atelectasis, suggesting benefit after receiving treatment with dornase alfa. However, the outcomes were possibly confounded by those receiving combination therapies, varying primary diagnoses, and varying end points evaluated. Dornase alfa was overall well tolerated, with only a few patients experiencing worsening atelectasis posttreatment. Conclusions: Dornase alfa may be considered as a therapeutic option in non–cystic fibrosis pediatric patients with pulmonary atelectasis, who require treatment intervention when conventional therapy is unsuccessful.

Inhaled Dornase alfa (Pulmozyme) as a noninvasive treatment of atelectasis in mechanically ventilated patients

BACKGROUND

Lobar or segmental collapse of the lung in mechanically ventilated patients is a common occurrence in the intensive care unit. Management is labor and time intensive and not highly effective.

METHODS

We conducted a randomized, placebo-controlled, double-blind pilot study to determine whether nebulized Dornase alfa improves radiologic and clinical outcomes in ventilated patients with lobar atelectasis. Drug or placebo was administered twice daily until extubation, death, or transfer. The primary outcome was the total chest x-ray score: secondary outcomes of interest were oxygenation, lung compliance, and rate of extubation over the first 5 days. The groups consisted of 14 intervention patients and 16 control patients.

RESULTS

There were no significant differences in "Total Chest X-Ray Score" or compliance over the 5 days of study. There was an improvement in oxygenation for the intervention group at day 5 (P = .03). In addition, this group was less likely to remain intubated over the first 24 hours of the study, a difference that did not persist over the course of the study.

CONCLUSIONS

Dornase alfa does not improve the appearance of atelectasis on chest radiographs, or the "Total Chest X-Ray Score" over the first 5 days of treatment in mechanically ventilated patients. The intervention group's higher rate of extubation during the first 24 hours as well as its improved oxygenation on day 5 were likely chance findings given the multiple potential confounders for extubation and low study power.

Pharmacotherapy of impaired mucociliary clearance in non-CF pediatric lung disease. A review of the literature

Mucoactive agents are used to treat a variety of lung diseases involving impaired mucociliary clearance or mucus hypersecretion. The mucoactive agents studied most frequently are N-acetylcysteine (NAC), recombinant human DNase (rhDNase), and hypertonic saline. Studies on the efficacy of these have been mainly conducted in adults, and in patients with cystic fibrosis (CF). The exact role of mucoactive agents in children with non-CF lung disease is not well established. We present an overview of the current literature reporting clinical outcome measures of treatment with NAC, rhDNase, and hypertonic saline in children.

Nebulised DNase in the treatment of life threatening asthma

A 25-year-old pregnant patient developed life-threatening asthma refractory to all standard treatment including anaesthetic agents. Ventilatory pressures continued to rise with impending cardio-respiratory arrest. The introduction of nebulised endotracheal DNase however resulted in a rapid and dramatic improvement with good clinical outcome.

DNase treatment for atelectasis in infants with severe respiratory syncytial virus bronchiolitis

Respiratory insufficiency due to respiratory syncytial virus (RSV) bronchiolitis is partly due to the abundance of thickened mucus and the inability to clear it from the airways. Mucus in RSV bronchiolitis contains necrotic inflammatory and epithelial cells. The viscoelastic properties of purulent airway secretions are largely due to the presence of highly polymerized deoxyribonucleic acid (DNA). Recombinant human deoxyribonuclease (rhDNase) is known to liquefy such mucus in patients with cystic fibrosis, whereas case reports described a beneficial effect in other respiratory disorders. The authors hypothesized that rhDNase would diminish atelectasis and mucus plugging in infants with severe RSV bronchiolitis.

Two infants with RSV bronchiolitis with massive unilateral atelectasis in whom mechanical ventilation was imminent due to exhaustion, and three mechanically ventilated infants (two neonates, one with bronchopulmonary dysplasia) with RSV bronchiolitis with pneumonia received treatment with 2.5 mg nebulized rhDNase twice daily.

Following administration of nebulized recombinant human deoxyribonuclease, clinical and radiological parameters improved quickly. Mechanical ventilation could be avoided in two infants while in three infants on artificial ventilation, clinical recovery started following the first dose of the drug. A therapeutic trial of recombinant human deoxyribonuclease may be an option in the treatment for atelectasis in severe or complicated respiratory syncytial virus bronchiolitis in infancy.

Rescue use of DNase in critical lung atelectasis and mucus retention in premature neonates

Excessive or thick pulmonary secretions are a common clinical challenge in the neonatal population. Mucus accumulation can cause many life-threatening complications, including plugging of the endotracheal tube and increasing the risk of pulmonary infections. We report 3 premature neonates who had critical pulmonary collapse secondary to mucous plugging. Different conventional methods to liquefy mucus and facilitate removal of secretions were exhausted to no avail. The rescue use of DNase was effective in reestablishing airway patency. Thus, this drug could be a valuable tool in treating atelectasis and mucus-plugging in mechanically ventilated, premature neonates.

Resolution of mucus plugging and atelectasis after intratracheal rhDNase therapy in a mechanically ventilated child with refractory status asthmaticus

OBJECTIVE

To report the dramatic resolution of unilateral mucus plugging and atelectasis in a mechanically ventilated child with refractory status asthmaticus after intratracheal recombinant human DNase (rhDNase) therapy.

DESIGN

Case report.

SETTING

Critical care unit.

PATIENT

A 7-yr-old boy with status asthmaticus, severe respiratory failure and barotrauma unresponsive to conventional therapy. Fiberoptic bronchoscopy confirmed widespread mucus impaction of the subsegmental bronchi of the left lung without response to bronchoscopic lavage.

INTERVENTIONS

Two 10-mg doses of intratracheal rhDNase were administered 8 hrs apart.

MAIN RESULTS

The left-sided atelectasis resolved 3 hrs after the first dose of rhDNase. Improvements in gas exchange and tidal volumes were sustained and particularly noticeable after the second dose. The patient was successfully extubated 26 hrs after receiving the rhDNase treatment without any adverse effects.

CONCLUSIONS

rhDNase should be considered as a potential therapy for refractory mucus plugging and atelectasis in intubated patients with status asthmaticus.