Low Dose Combination of Morphine and Ketamine Versus Standard Dose Morphine Alone in Pain Control During Change of Dressing in Adult Burn Patients. A Parallel Group, Randomized Control Trial

Abstract

Background: Burn injuries occur when the skin is exposed to excessive heat with resultant extensive tissue damage. A cardinal element in the management of burn injuries is the performance of change of dressing that normally results in excruciating pain. Health care providers thus have a responsibility to mitigate this pain using either pharmacological or non-pharmacological means. Research objective and hypothesis: This study aimed to establish the effect of a combination of low dose morphine and ketamine compared to standard dose morphine alone on pain control during dressing change in adult burn patients. It hypothesized that the response to a combination of ketamine and morphine is clinically inferior to the response to morphine alone against an alternative that it is clinically non - inferior. Methodology: This study was a Non-Inferiority Randomized Controlled Trial consisting of a total of 100 adult subjects randomized into two parallel groups. It was conducted at Kenyatta National Hospital Burns Unit and Ward 4D. Statistical Analysis involved fitting linear regression models, model building and verification of model assumptions in SAS 9.4 and R Studio version 3.1.1 (2014-07-10). Ethical clearance was obtained from Kenyatta National Hospital/ University of Nairobi Ethics and Research Committee. Results: A total of 100 subjects were enrolled into this study and randomized into the control and treatment arms. Comparison of pain scores between the control and treatment arms revealed pain control in the low dose ketamine/morphine combination was non inferior to standard dose morphine alone. In addition, the low dose ketamine/morphine combination experienced more adverse effects compared to the standard dose morphine alone group. However, most of the adverse effects were minor and could be easily mitigated.