Helium-oxygen therapy for pediatric acute severe asthma requiring mechanical ventilation.
OBJECTIVE
To illustrate the use of helium-oxygen gas mixtures as therapy for pediatric patients with acute severe asthma requiring conventional mechanical ventilation.


METHODS
Retrospective review.


METHODS
Tertiary care children's teaching hospital.


METHODS
All mechanically ventilated patients with severe asthma admitted to the pediatric intensive care unit from August 1994 to October 2000.


METHODS
Within 24 hrs of intubation or admission, patients were stabilized on volume ventilation, bronchodilator therapy, corticosteroids, and antibiotics when indicated. Hypercapnia was permitted while maintaining arterial blood gas pH > or =7.25. A helium-oxygen gas mixture then was begun with helium flow set at 5-7 L/min, and oxygen flow was titrated to maintain desired oxygen saturation. Only sedated, chemically paralyzed patients with adequate pre-helium-oxygen and post-helium-oxygen measurements were statistically analyzed.


RESULTS
Twenty-eight mechanically ventilated patients with severe asthma placed on helium-oxygen gas mixtures were identified who met study entry criteria. Mean patient age was 8.8 yrs (range, 1.1-14.6). Before helium-oxygen therapy began, mean peak inspiratory pressure was 40.5 +/- 4.2 cm H(2)O, mean arterial blood gas pH was 7.26 +/- 0.05, and mean CO(2) partial pressure was 58.2 +/- 8.5 torr. After patients were placed on helium-oxygen therapy, there was a significant decrease in mean peak inspiratory pressure to 35.3 +/- 3.0 cm H(2)O. Mean pH increased significantly to 7.32 +/- 0.06, and mean partial pressure CO(2) decreased significantly to 50.5 +/- 7.4 torr. Initial mean inspired helium was 57 +/- 4% (range, 32-74). Mechanical ventilation days ranged from 1 to 23 days (mean, 5.0). Hospital stay ranged from 4 to 29 days (mean, 10.1), with an average pediatric intensive care unit stay of 6.9 days (range, 2-24). There were two incidences of pneumothorax.


CONCLUSIONS
In the pediatric patient with severe asthma requiring conventional mechanical ventilation, helium-oxygen administration appears to be a safe therapy and may assist in lowering peak inspiratory pressure and improving blood gas pH and partial pressure CO(2).
Abd-Allah
Shamel A
SA
Pediatric Critical Care Division and Respiratory Care Department, Loma Linda University School of Medicine, Loma Linda, CA, USA.
Rogers
Mark S
MS
Terry
Michael
M
Gross
Matthew
M
Perkin
Ronald M
RM
D000208:Acute Disease; D000293:Adolescent; D000367:Age Factors; D001249:Asthma / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology / Q000628:therapy*; D002245:Carbon Dioxide / Q000097:blood; D002648:Child; D002675:Child, Preschool; D006371:Helium / Q000008:administration & dosage*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007223:Infant; D015278:Intensive Care Units, Pediatric; D007902:Length of Stay; D010100:Oxygen / Q000008:administration & dosage* / Q000097:blood; D012121:Respiration, Artificial; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D013997:Time Factors
D002245:Carbon Dioxide; D006371:Helium; D010100:Oxygen