Background: Bone marrow aspiration and Biopsy is a painful procedure done in children withrnhematologic disorders. The ideal drug administered during this procedure should have sedativernand analgesic effect including hemodynamic stability and recovery with minimal side effects.rnKetamine and propofol mixture is widely used for its combined effect of amnesia and analgesiarnas well as heamodynamic stability and decreased post procedural adverse events . This studyrnmainly aims to compare the effectiveness of ketofol in 1:2versus 1:3 combinations for pediatricsrnundergoing BMA and/or Biopsy . rnObjectives: The objective of this study was to compare the effectiveness of ketofol in 1:2 versusrn1:3 combinations for Procedural sedation and analgesia in children undergoing Bone marrowrnaspiration and/or Biopsy at Tikur Anbessa Specialized Hospital. rnMethodology :In this prospective cohort study128 pediatric patients age 1â€“ 12 years undergoing rnBMA and/or Biopsy with ketofol 1:2 or 1:3 combination at Tikur Anebessa Specialized Hospitalrnfrom December 2019-March 2020 were included. Hemodynamic and respiratory variables, werernnoted 1 min before induction (baseline) and every 10 minute until the procedure ends. Ramsayrnsedation score immediately after induction and every 10 minute during the procedure wasrnrecorded. Total sedative and analgesia use was recorded intraoperativley. Post proceduralrnadverse events occurrence was followed in the postoperative period. Normality of the data wasrnchecked using Kolmogorov-smirnov test and analyzed using student t test for normallyrndistributed data and chi-square test for categorical data. Non- parametric data was analyzedrnusing Mann â€“Whitney U test with 95% CI and p- value less than 0.05 is considered asrnstatistically significant. rnResults: - ketofol 1:2 group ( n=64) compared with ketofol 1:3 group ( n=64) had similarrnsedation level assessed by RSS , heamodynamic and respiratory outcome, as well as generalrnpostoperative adverse events profile, but the total intraoperative analgesia consumption wasrnsignificantly higher in ketofol 1:3 group (29.7%) when compared to ketofol 1:2 group (7.8%)rnwith p=0.002. rnConclusion and recommendation: -Sedation level, general hemodynamic and respiratory profilernincluding post procedural adverse events were comparable between groups. Higherrnintraoperative analgesia use in ketofol 1:3 group shows the need for additional analgesia in thisrncombination. We recommend ketofol 1:2 combination for pediatrics undergoing BMA and/orrnBiopsy, due to decreased intraoperative analgesia requirement seen in the group.