Compartment syndrome and patient-controlled analgesia in children--analgesic complication or early warning system?

We present two cases of children who developed compartment syndrome after upper limb fractures. Morphine patient-controlled analgesia was used in a bolus-only mode for analgesia (bolus 20 microg/kg, five minute lockout and hourly limit of 150 microg/kg). An increase in patient-controlled analgesia use was observed up to 12 hours before the decision was made to proceed to fasciotomy but neither child exceeded the hourly limit or had an excessive increase in pain scores. Clinical risk factors for compartment syndrome should be identified and appropriate monitoring instituted. A subtle increase in patient-controlled analgesia use may be an early indicator of impending compartment syndrome before classical signs such as reporting of pain, pallor paraesthesiae, paralysis and pulselessness develop. These cases and review of the literature suggest techniques which may assist earlier diagnosis of compartment syndrome include setting a more conservative hourly limit of morphine patient-controlled analgesia such as 80 to 100 microg/kg/hour and graphing of patient-controlled analgesia demands and boluses, pain scores at rest and pain scores with passive flexion and extension of digits. These practices could identify trends that pain or analgesia requirement is increasing leading to earlier diagnosis of compartment syndrome.