Effect of tidal volume in children with acute hypoxemic respiratory failure.
OBJECTIVE
To determine if tidal volume (VT) between 6 and 10 ml/kg body weight using pressure control ventilation affects outcome for children with acute hypoxemic respiratory failure (AHRF) or acute lung injury (ALI). To validate lung injury severity markers such as oxygenation index (OI), PaO2/FiO2 (PF) ratio, and lung injury score (LIS).


METHODS
Retrospective, January 2000-July 2007.


METHODS
Tertiary care, 20-bed PICU.


METHODS
Three hundred and ninety-eight endotracheally intubated and mechanically ventilated children with PF ratio <300. Outcomes were mortality and 28-day ventilator free days.


RESULTS
Three hundred and ninety-eight children met study criteria, with 20% mortality. 192 children had ALI. Using >90% pressure control ventilation, 85% of patients achieved VT less than 10 ml/kg. Median VT was not significantly different between survivors and non-survivors during the first 3 days of mechanical ventilation. After controlling for diagnostic category, age, delta P (PIP-PEEP), PEEP, and severity of lung disease, VT was not associated with mortality (P > 0.1), but higher VT at baseline and on day 1 of mechanical ventilation was associated with more ventilator free days (P < 0.05). This was particularly seen in patients with better respiratory system compliance [Crs > 0.5 ml/cmH2O/kg, OR = 0.70 (0.52, 0.95)]. OI, PF ratio, and LIS were all associated with mortality (P < 0.05).


CONCLUSIONS
When ventilating children using lung protective strategies with pressure control ventilation, observed VT is between 6 and 10 ml/kg and is not associated with increased mortality. Moreover, higher VT within this range is associated with more ventilator free days, particularly for patients with less severe disease.
Khemani
Robinder G
RG
Department of Anesthesia and Critical Care Medicine, Children's Hospital Los Angeles, 4650 Sunset Blvd, Mail Stop 12, Los Angeles, CA 90027, USA. rkhemani@chla.usc.edu
Conti
David
D
Alonzo
Todd A
TA
Bart
Robert D
RD
Newth
Christopher J L
CJ
D055371:Acute Lung Injury / Q000503:physiopathology; D002675:Child, Preschool; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D008176:Lung Volume Measurements / Q000379:methods; D008297:Male; D011175:Positive-Pressure Respiration; D012131:Respiratory Insufficiency / Q000401:mortality / Q000503:physiopathology*; D012189:Retrospective Studies; D013990:Tidal Volume / Q000502:physiology*