Objective: We aimed to evaluate the efficacy, morphine requirements and side effects in patients managed with patient-controlled analgesia postoperatively.
Methods: Eighty-seven patients, 7 to 22 (median 14) years of age, after orthopedic, abdominal or thoracic surgery, were studied retrospectively. All patients had a preset standard continuous morphine infusion of 10 micrograms/kg/h, 20 micrograms/kg bolus dose, 8 min lock-out time and 100 micrograms/kg/h maximal dose. All patients were additionally treated with non-steroidal anti-inflammatory drugs. Respiratory rate, pain intensity, morphine requirements and nausea/vomiting were evaluated every 3 hours. Pain was assessed using 6-point scale (1-no pain, 6-the worst pain).
Results: Median time for pain management was 51 h. Median (range) used dose of morphine was 19.9 (4.9-75.2) micrograms/kg/h. Sixty-one percent of the patients had a mean pain score of 1 or 2, 26%--3, 13%--4 or 5. Nausea/vomiting occurred in 78% of cases. Respiratory rate less than 10 breaths per min was observed in 5.7% of patients. No patient required opioid antagonist to treat respiratory depression.
Conclusions: In the majority of patients patient-controlled analgesia was effective and used doses of morphine were low. Though nausea/vomiting was the most common side effect, decreased respiratory rate was observed in some patients. Regular patient evaluation for vital signs and side effects is recommended.