Morphine consumption and respiratory depression in children receiving postoperative analgesia from continuous morphine infusion or patient controlled analgesia

Thirty children, aged between five and 15 years, were randomly allocated to receive postoperative analgesia from continuous morphine infusion (CMI) or patient controlled analgesia (PCA), also using morphine. The children's morphine consumption, respiratory rates, oxygen saturations and observation points during which they were sleeping were recorded during two periods, one on the day of operation and one the following day. The median dose of morphine consumed by the children using PCA was significantly larger than that consumed by the children having continuous infusions. Children aged between nine and 15 years using PCA had significantly lower minimum respiratory rates and minimum oxygen saturations than similarly aged children receiving continuous infusions. There was no significant difference between the PCA and CMI groups in the number of observation times that the children were asleep or in the minimum respiratory rates and minimum oxygen saturations in the awake and sleeping children.