The Effect of Ketamine Administration on Pain Control in Painful Crisis of Sickle Cell Anemia Patients during Childhood: A Retrospective Observational Study

Background: Sickle cell anemia (SCA) is a hemoglobinopathy as a result of substitution of glutamic acid with valine in the 6th position of the β globin chain. The vaso-occlusive crises of patients are often caused by pain that requires in-patient treatment. The attack rate is reported to changed between 0.5-1.0 attacks per year per patient. It could be reach up to 10% in 5% of patients. Identification of the SCA painful crisis and the determination of appropriate treatment is very important for the pain relief. Recently studies support that ketamine treatment is beneficial in patients who do not respond to traditional methods. Ketamine is a non-competitive antagonist at the NMDA receptor. We used retrospective visual analogue scale (VAS) scoring system in acute painful crisis patients and then applied ketamine and tramadol to investigate the effect of treatment and side effects and the maximum change in pain score within the first hour after drug administration retrospectively. The aim of this study is evaluate the level of ketamine effect in painful crises.

Methods: Patients older than 6 years of age with acute painful crisis, defined as VAS of greater or equal to 4 were enrolled.The retrospective data was collected from electronic records and included age, sex, vital signs, changes in pain score within 1 hour, and side effects. Ketamine (0.25 mg / kg / dose) and tramadol (0.1-0.4 mg / kg / h) were administered. Patients with a pain score of <4 or a decrease of ≥3 points in VAS were considered to be responsive.

Results: Ketamine group (n = 16), 6 female (37.5%), 10 male (63.5%) and the mean age was 15.4 (7-21) years. Tramadol group (n = 31) 15 female (48%), 16 male (52%) and the mean age was 15.6 (6-21) years. The age and sex groups were similar (p> 0.05). After drug administration, vital signs were observed in all patients in normal range to their age. In the tramadol and ketamine groups, the number of patients who responded at 20 minutes were 9(29%)-9(56%), 12(38%)-11(68%) (p<0.05) at 60 minutes. Sixteen patients (51.6%) responded in the 6th hour of the tramadol group, no evaluate in ketamin group. No life-threatening side effects was observed in any patient.

Conclusion: In the treatment of painful crises, ketamine administration was found to be more effective than tramadol in the first hour. Due to the longer duration of the initial effect of tramadol treatment, ketamine should be considered as an option in the rapid treatment of painful crises.