Retrospective analysis of predisposing factors for difficult lumbar punctures requiring image guidance in pediatric oncology patients

Success and complications in lumbar punctures of pediatric patients with leukemia: a study protocol for a randomized clinical crossover trial of a bioimpedance needle system versus conventional procedure

BACKGROUND

Acute lymphoblastic leukemia (ALL) is the most common malignancy diagnosed in children. At present, the long-term survival from pediatric ALL is well over 90%. However, the probability of event-free survival is reduced if the lumbar puncture (LP) procedures at the beginning of the patient's intrathecal therapy cause blood leakage into the spinal canal and blast cells contaminate the cerebrospinal fluid. According to the literature, such traumatic LP procedures concern one out of five pediatric patients with ALL. Recently, a novel medical device measuring the tissue bioimpedance at the tip of a spinal needle was found feasible in pediatric patients with ALL. The LP procedure was successful at the first attempt in 80% of procedures, and the incidence of traumatic LPs was then 11%. The purpose of the present study is to compare the bioimpedance spinal needle system with the standard clinical practice resting on a conventional spinal needle and investigate its efficacy in clinical practice.

METHODS

The study is a multicenter, randomized, two-arm crossover noninferiority trial of pediatric hemato-oncology patients that will be conducted within the usual clinical workflow. Patients' LP procedures will be performed alternately either with the IQ-Tip system (study arm A) or a conventional Quincke-type 22G spinal needle (study arm B). For each enrolled patient, the order of procedures is randomly assigned either as ABAB or BABA. The total number of LP procedures will be at least 300, and the number of procedures per patient between two and four. After each study LP procedure, the performance will be recorded immediately, and 1-week diary-based and 4-week record-based follow-ups on symptoms, complications, and adverse events will be conducted thereafter. The main outcomes are the incidence of traumatic LP, first puncture success rate, and incidence of post-dural puncture headache.

DISCUSSION

The present study will provide sound scientific evidence on the clinical benefit, performance, and safety of the novel bioimpedance spinal needle compared with the standard clinical practice of using conventional spinal needles in the LP procedures of pediatric patients with leukemia.

TRIAL REGISTRATION

ISRCTN ISRCTN16161453. Registered on 8 July 2022.

Traumatic lumbar punctures in diagnostic and intrathecal treatment punctures of pediatric hemato-oncology patients

Successful first diagnostic lumbar puncture (LP) is crucial because intrathecal chemotherapy has not yet protected the central nervous system against cancer cells. If blood contaminates the cerebrospinal fluid (CSF) with blasts, they may enter the central neural system and compromise the patient's health. We retrospectively determined the incidence of traumatic lumbar punctures (TLP) in 2,507 LPs of 250 pediatric hemato-oncology patients aged from one to 18 years, including both diagnostic and intrathecal treatment procedures, and 2,617 LPs of 1,525 other age-matched pediatric patients. We used ≥10 erythrocytes/µL in the CSF sample as the criterion of TLP. TLPs were less frequent in hemato-oncology patients than in other patients (31.6% vs. 48.5%, p < 0.0001). The incidence of TLP was significantly lower in the first diagnostic LP than in subsequent intrathecal treatment LPs (20.5% vs. 31.6%, p = 0.0046). According to logistic regression analysis, the odds of TLP was 1.6-fold if the LP procedure was not performed in the hemato-oncology department. The odds of the patient's next LP being traumatic were threefold if the previous first LP was traumatic. A week or less time between the first and next LP tripled the odds of TLP as well. The patient's age category was not significantly associated with the incidence of TLP. Given the risks of TLP, hemato-oncology patients' first diagnostic LP should include administration of chemotherapy, as generally recommended, and be performed under general anesthesia or deep sedation by an experienced physician to optimize not only the success of the first LP procedure but also following procedures.

Bioimpedance spinal needle provides high success and low complication rate in lumbar punctures of pediatric patients with acute lymphoblastic leukemia

In this prospective single-arm study of 50 pediatric patients with acute lymphoblastic leukemia (ALL), we evaluated the clinical performance of a novel bioimpedance spinal needle system in 152 intrathecal treatment lumbar punctures (LP) of these patients. The system detects in real-time when the needle tip reaches the cerebrospinal fluid (CSF) in the spinal canal. The success was defined as getting a CSF sample and/or administering the intrathecal treatment with one needle insertion. Incidence of traumatic LP (TLP) was defined as ≥ 10 erythrocytes/µL of CSF. Post-procedural complications were monitored with a one-week diary and one-month register follow-up. The success of the first attempt was 79.5%, with the CSF detection sensitivity of 86.1%. The incidence of TLP was 17.3%. A successful first attempt was associated with a significantly lower incidence of TLP (10% vs 40%, p = 0.0015). During the week after the procedure, the incidence of post-dural puncture headache was 6%. During the follow-up, no major complications were observed. In conclusion, the novel bioimpedance spinal needle system achieved a high success rate and low incidence of TLP and other complications in pediatric patients with ALL in a real-world clinical setting, indicating clinical utility for this system in pediatric hemato-oncology.