Measure | No surgery (n=202) | Surgery (n=19) | p Value |
---|---|---|---|

Where applicable, values are mean (SD). The test of significance was based on the χ^{2} test of independence for dichotomous measures and one way analysis of variance for continuous measures. | |||

*Pco_{2} values for nine children who were not ventilated were set to an arbitrary value of 40. Excluding these nine children does not materially alter the strength of this association. | |||

% Male | 58.6 | 47.4 | > 0.30 |

Gestational age (weeks) | 27.1 (2.6) | 26.3 (1.9) | > 0.15 |

Birth weight (g) | 1007 (293) | 940 (234) | > 0.30 |

CRIB score | 5.4 (4.2) | 7.3 (4.3) | > 0.05 |

% IVH grade 3 or 4 | 21.2 | 94.7 | < 0.0001 |

Max Pco_{2} | 57.2 (16.0) | 59.9 (9.6) | > 0.4 |

% Hypertension | 50.3 | 42.1 | > 0.4 |

% Inotropic support | 54.7 | 89.5 | < 0.005 |

% Antenatal corticosteroids | 78.3 | 68.4 | > 0.30 |