The Impact of Preemptive Intramuscular Methadone or Piroxicam in Controlling Pain after Lower Limb Orthopedic Surgery under General Anesthesia

This research was conducted to investigate the impact of preemptive intramuscular methadone or piroxicam in controlling pain after lower limb orthopedic surgery under general anesthesia.
This randomized clinical trial study was carried out on 94 patients undergoing lower limb orthopedic surgery, in three groups. In the first group, 20 mg piroxicam was intramuscularly injected into the patient's deltoid muscle after anesthesia and before surgery. In the second group, 0.15 mg/kg intramuscular methadone was injected into the patient's deltoid muscle; and in the third group, the same volume of normal saline was injected intramuscularly. Then, the pain intensity in all three groups were evaluated and recorded using visual analog scale (VAS) in recovery and ward up to 24 hours. Additionally, information such as systolic, diastolic, and mean arterial pressure, and saturated oxygen percentage was recorded during the surgery. Finally, the collected data were analyzed using SPSS software.
Findings: The intensity of pain 30 minutes after the surgery in the piroxicam group with a mean of 1.90 ± 0.36 was significantly higher than methadone group with a mean of 0.20 ± 0.17 and both groups received the drug showed significant difference with control group (P 0.05 for all).
Methadone has an early preventive impact on pain intensity reduction compared to piroxicam, while multiplicity of side effects associated with the use of methadone was more than piroxicam. Finally, pain severity was evaluated equal in two groups for up to 24 hours after the surgery.