Volume of Cerebrospinal Fluid Removal Prior to Intrathecal Chemotherapy Administration: A Survey of Canadian Hematology/Oncology Practitioners,

Intrathecal (IT) chemotherapy is administered to patients with leukemia to treat both central nervous system (CNS) disease and to prevent the spread of leukemia into the CNS. No studies that assess the exact volume of cerebrospinal fluid (CSF) that needs to be removed prior to the administration of IT chemotherapy exist, even though guidelines are published in some pediatric chemotherapy treatment protocols. We plan to study the side effects of different volumes of CSF removal prior to IT chemotherapy administration on patient quality of life in a randomized controlled trial. Prior to that study, we collected data on the practices of IT chemotherapy administration by hematology/oncology practitioners at the 17 pediatric oncology centers in Canada.

We designed a 12 question survey, which was sent electronically to all hematology/oncology practitioners in Canada who perform lumbar puncture (LP) with IT chemotherapy administration. Included in our survey were consultants, nurse practitioners, pediatricians, clinical assistants and fellows. We identified practitioners using the Children's Oncology Group member database and verified our lists by contacting the head of each Canadian hematology/oncology division, as well as the training program director at each of these centers, to ensure all eligible practitioners were included. Three follow up email reminders about the survey were sent to the same group of practitioners. The data was collected electronically and descriptive statistics were obtained.

We identified a total of 178 pediatric hematology/oncology practitioners at all Canadian centers who perform LPs with IT chemotherapy. The survey was completed by 112 (62.9%) of these individuals of whom 107 performed LPs with IT chemotherapy and 5 did not. Of these respondents, 65.4% were consultant pediatric hematologist/oncologists, 24.3% were fellows in pediatric hematology/oncology, 6.5% were clinical assistants, 2.8% were nurse practitioners, and 0.9% were pediatricians. Thirty one percent had been practicing hematology/oncology for more than 15 years, 27.1% for less than 5 years, 26.2% for 5–10 years, and 15.9% for 10–15 years. Most respondents (29.9%) reported that 6–10 LPs with IT chemotherapy are performed at their institution every week, followed by 11–15 (17.8%), 0–5 (13.1%) and 21–25 (11.2%). Most respondents had performed more than 500 LPs with IT chemotherapy (45.3%) in their career to date, followed by 34% having performed 100–500 LPs with IT chemotherapy.

The volume of CSF removal prior to IT chemotherapy administration varied among respondents. The most common volume removal was 3 ml (17.9%), followed by half the volume of IT chemotherapy administered (15.1%), then 2 and 4 ml (14.2% each), then 1 ml (13.2%) and finally equal to the total volume of IT chemotherapy injected (9.4%). Chemotherapy was injected over 30–60 seconds 41.9% of the time, followed by over less than 30 seconds (28.6%) and over 1–2 minutes (19%). The majority of practitioners learned how much CSF to remove and the speed with which to inject IT chemotherapy from a consultant hematologist/oncologist (88.8%). A little more than a half were aware that protocols have guidelines on how much CSF to remove (58.1%), and of those aware of these guidelines the majority (57.1%) do not follow them. When asked practitioners to list all of the reasons for why they did not follow the recommended guidelines, and the reasons given were that they were not obligatory (41.9%), that there was no evidence for the guidelines (40.0%), that there was pressure from those around to perform the procedure and administer the IT chemotherapy quickly (32.3%), and that practitioners themselves did not have the time to collect all of the CSF recommended (29.0%).

This large survey of Canadian pediatric hematology/oncology practitioners, assessing the practice of IT chemotherapy administration, showed that there is large variation in the volume of CSF that is removed prior to IT chemotherapy administration and the speed of IT chemotherapy injection. In the majority of cases, published guidelines in chemotherapy treatment protocols are not followed. A study examining the side effects of different volumes of CSF removal will provide much needed evidence for this clinical procedure.

No relevant conflicts of interest to declare.