Early Initiation of Ketamine Infusion for Pain Management in Pediatric BMT Patients with Mucositis

Background: As many as 90% of children undergoing hematopoietic stem cell transplant (HSCT) will experience painful mucositis. The mainstay of treatment for these children has been opioid analgesia which can be associated with sedation and respiratory depression. Additionally, these children may experience heightened opioid tolerance and physiologic dependence contributing to lengthy admissions. Ketamine is an anesthetic and analgesic which has been used successfully in conjunction with opioids in the treatment of painful mucositis. This study aimed to reduce total opioid use per day by 10% and overall pain scores by 2 in pediatric patients with mucositis undergoing HSCT through initiation of ketamine at the same time as an opioid patient-controlled analgesia (PCA).

Methods: Beginning April 2022, HSCT patients (both autologous and allogeneic) at Children’s Hospital Colorado were started on ketamine infusion in conjunction with an opioid PCA for management of painful mucositis. Mucositis severity and duration, opioid consumption, pain and functional scores, time of initiation of ketamine therapy, ketamine side effects, and duration of PCA and ketamine therapy were recorded for a retrospective (April 2021- March 2022, n=6) and a prospective cohort (April 2022- April 2023, n=17). A 2-sample-T-test was used to calculate the difference in mean cumulative opioid use per day and the mean 24-hour average pain scores between the retrospective and prospective groups.

Results: 71% of children in the prospective group underwent ketamine initiation alongside an opioid PCA. Patients in this group had a 46% reduction in mean cumulative opioid use per day (CI 1.265-2.318, p=0.000). Reduction in 24-hour pain scores between the retrospective and prospective groups was 1.18, failing to meet our goal of 2.0. However, there was still a statistically significant difference in mean scores (CI 0.499-1.860, p=0.001). Additionally, this intervention was tolerated well and only 1 patient (16%) was intolerant of ketamine side effects in the prospective cohort.

Conclusions: Initiation of ketamine alongside an opioid PCA for the treatment of mucositis pain is safe and significantly reduces cumulative opioid exposure and 24-hour pain scores in children undergoing HSCT.