Pressure-controlled ventilation in children with severe status asthmaticus.
OBJECTIVE
The optimum strategy for mechanical ventilation in a child with status asthmaticus is not established. Volume-controlled ventilation continues to be the traditional approach in such children. Pressure-controlled ventilation may be theoretically more advantageous in allowing for more uniform ventilation. We describe our experience with pressure-controlled ventilation in children with severe respiratory failure from status asthmaticus.


METHODS
Retrospective review.


METHODS
Pediatric intensive care unit in a university-affiliated children's hospital.


METHODS
All patients who received mechanical ventilation for status asthmaticus.


METHODS
Pressure-controlled ventilation was used as the initial ventilatory strategy. The optimum pressure control, rate, and inspiratory and expiratory time were determined based on blood gas values, flow waveform, and exhaled tidal volume.


RESULTS
Forty patients were admitted for 51 episodes of severe status asthmaticus requiring mechanical ventilation. Before the institution of pressure-controlled ventilation, median pH and Pco(2) were 7.21 (range, 6.65-7.39) and 65 torr (29-264 torr), respectively. Four hours after pressure-controlled ventilation, median pH increased to 7.31 (6.98-7.45, p <.005), and Pco(2) decreased to 41 torr (21-118 torr, p <.005). For patients with respiratory acidosis (Pco(2) >45 torr) within 1 hr of starting pressure-controlled ventilation, the median length of time until Pco(2) decreased to <45 torr was 5 hrs (1-51 hrs). Oxygen saturation was maintained >95% in all patients. Two patients had pneumomediastinum before pressure-controlled ventilation. One patient each developed pneumothorax and subcutaneous emphysema after initiation of pressure-controlled ventilation. All patients survived without any neurologic morbidity. Median duration of mechanical ventilation was 29 hrs (4-107 hrs), intensive care stay was 56 hrs (17-183 hrs), and hospitalization was 5 days (2-20 days).


CONCLUSIONS
Based on this retrospective study, we suggest that pressure-controlled ventilation is an effective ventilatory strategy in severe status asthmaticus in children. Pressure-controlled ventilation represents a therapeutic option in the management of such children.
Division of Critical Care Medicine, Department of Pediatrics, Children's Hospital of Michigan, Wayne State University School of Medicine, Detroit, MI 48201, USA. Asarnaik@med.wayne.edu
Ashok P
AP
Sarnaik
Kshama M
KM
Daphtary
Kathleen L
KL
Meert
Mary W
MW
Lieh-Lai
Sabrina M
SM
Heidemann
D000142:Acidosis, Respiratory / Q000209:etiology / Q000628:therapy; D000293:Adolescent; D001784:Blood Gas Analysis; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D015278:Intensive Care Units, Pediatric; D008297:Male; D011175:Positive-Pressure Respiration; D012189:Retrospective Studies; D013224:Status Asthmaticus / Q000097:blood / Q000150:complications / Q000628:therapy*; D013990:Tidal Volume