Review of analgesia use in the intensive care unit after heart surgery

OBJECTIVE: To investigate analgesic prescription patterns and administration in postoperative cardiac surgery patients in the ICU in a tertiary hospital. METHOD: The audit was registered with the institutional Quality Improvement Committee. A sample of 73 postcardiac surgery patients who were admitted to the ICU during a 12-month period in 2003-2004 were reviewed. RESULTS: All patients received opioid analgesia in the ICU. On the first postoperative day, patients received a mean of 1.27 mg morphine equivalents per hour, while the 25 patients present in the ICU for a second day received a mean of 0.84 mg morphine equivalents per hour. No relationship was seen between Day 1 administration of analgesia and age, sex or use of an internal mammary artery (IMA) graft or Day 2 administration and sex or use of IMA. A slight negative relationship existed between morphine administered on Day 2 and age (r = ?0.38, P = 0.06). Paracetamol or paracetamol plus codeine (8 mg or 30 mg) was administered to 70 patients (96%), but was prescribed 6-hourly in 24 patients (33%) and actually administered 6- hourly in 32 (44%). No analgesia was administered in 23% of patients before removal of chest drains. The average time to extubation was 15.7 h (SD, 12.1 h). A moderate correlation between time to extubation and morphine equivalents per hour on Day 1 was demonstrated (r=0.43, P < 0.001). The average duration of ICU stay was 28.1 h. A routine pain assessment score was not charted for any the 73 patients. CONCLUSION: We recommend introducing scoring of patient pain in the ICU, both at rest and with movement, and provision of a designated area on the ICU flow chart for these scores. Paracetamol or other simple analgesics could be prescribed regularly, and staff need education about premedication of patients before removal of chest drains.