The Analgesic Effect of Morphine and Dexmedetomidine Intravenous Patient-Controlled Analgesia method to Control Pain After Open Cardiac Surgery: A Randomized Control Trial

Background: After major surgeries, such as abdominal or thoracic surgery, the majority of patients experience moderate to severe pain that may not be optimally controlled. Inadequate pain relief may lead to complications that can hinder rehabilitation and slow recovery. Objectives: Post-operative pain is one of the most common complaints in surgery wards especially in open cardiac surgeries. The current study compared effectiveness of the patient controlled anesthesia (PCA) method, intravenously with morphine (MO) and dexmedetomidin (DEX) to reduce post-operative pain after open cardiac surgery. Patients and Methods: The study was a double blind randomized clinical trial. One hundred candidates for open cardiac surgery were enrolled in the study and randomly assigned into two groups of MO and DEX. The patient-controlled intravenous analgesia (PCIA) pump was administered to all of the subjects, post-recovery, after insertion of catheter and filled with selected MO or DEX. Then visual analogue scale for pain severity was measured and recorded at 2, 4, 6, 8,10,12, 14, 16 and 18 hours post-operatively. SPSS V.16 was used for data analysis. Results: Findings of the study showed a significant difference regarding the level of pain among the patients under treatment of MO and DEX at 2, 4, 6, 8, 10 and 12 hours after the surgery, whereas there was no significant difference at 14, 16 and 18 hours. However, the pain score was lower during the first 12 hours of follow-ups in both groups. Furthermore, intubation time in DEX-PCA group was shorter than that of MO group. It was also observed that the DEX pump group had required less intravenous morphine than MO pump group in the intensive care unit (ICU). Conclusions: The study findings showed that post-operative pain was favorably reduced in both DEX and MO-PCIA groups after open cardiac surgery. Dexmedetomidin provides beneficial effects on pain control after cardiac surgery, with less adverse effects such as nausea, itching, atelectasis, intubation time, respiratory depression and intravenous morphine consumption.