Safety of lumbar punctures in patients with thrombocytopenia

Real-world practice of acute leukemia intrathecal chemotherapy administration: A Mexican nationwide survey

INTRODUCTION

Intrathecal chemotherapy is a mainstay component of acute lymphoblastic leukemia treatment. In Mexico, there is a considerable practice variability in aspects, such as the manner of preparation and the administration technique.

OBJECTIVE

Our objective was to describe the different techniques used for the application of ITC and review the existing recommendations in the literature.

METHOD

A cross-sectional, nationwide survey study was conducted by an electronic questionnaire sent to hematologists and oncologists in Mexico. We collected demographic data, personal experience, intrathecal chemotherapy techniques, drug preparation and postprocedural conduct.

RESULTS

We received 173 responses. Twenty percent had an anesthesiologist administering sedation and pain management. The platelet count considered safe was 50 × 109/L in 48% of the participants. In 77% (n = 133) of the cases, the conventional needle with stylet used was, 49% did not receive any added diluent in the intrathecal chemotherapy and only 42% were recommended to rest in a horizontal position for more than 30 min.

CONCLUSION

We identified a considerable variation in the administration of intrathecal chemotherapy across the hematologists in Mexico. We discuss the implications and opportunities in reducing the variation in our setting, highlighting the unmet need to establish guidelines that should be evaluated by the Mexican professional society to produce a position paper regarding practice standardization.

Can we lower the platelet threshold of ≥ 50 × 109/L for performing a lumbar puncture safely in patients with hematological malignancies?

Lumbar punctures (LP) are routinely used to administer intrathecal chemotherapy for children and adults with hematologic malignancies. The current guidelines suggest a platelet threshold of ≥ 50 × 10⁹/L prior to LP for intrathecal chemotherapy (ITC). This can be challenging in patients with hematological malignancies who are thrombocytopenic. We conducted a retrospective chart review of 900 LPs for ITC and compared adverse events in patients with a platelet count of ≥ 50 × 10⁹/L and < 50 × 10⁹/L. Cohort 1 included 682 LPs (75.8%) with a pre-procedure platelet count ≥ 50 × 10⁹/L, and cohort 2 included 218 LPs (24.2%) with a pre-procedure platelet count < 50 × 10⁹/L. Cohort 2 was further subdivided into pre-procedure platelet counts of 41 × 10⁹/L-49 × 10⁹/L (n = 43), 31 × 10⁹/L-40 × 10⁹/L (n = 77), 21 × 10⁹/L-30 × 10⁹/L (n = 84), and 11 × 10⁹/L-20 × 10⁹/L (n = 14). Among 900 LP procedures, a pre-procedure platelet count < 50 × 10⁹/L did not demonstrate a higher rate of post-procedure adverse events (6.5% vs 6.8%, p = 0.8237). When cohort 2 was further stratified, the cohort with a pre-procedure platelet count of 21 × 10⁹/L-30 × 10⁹/L had the highest percentage of complications from LP (9.5%) and the highest rates of traumatic taps with observed LP RBC count > 200 (35.7%, p = 0.0015). The rate of red blood cells (RBC) in the CSF was significantly higher in the group with platelets < 50 × 10⁹/L with observed LP RBC count ≥ 200 (31.2% vs 20.5%, p = 0.0016), ≥ 500 (27.1% vs 14.6%, p < 0.0001), and ≥ 1000 (23% vs 11.6%, p < 0.0001). No instances of epidural hematomas were seen. We found no significant difference in bleeding complications between patients undergoing LPs for ITC with a platelet count above or below 50 × 10⁹/L.

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

Success rates of lumbar punctures (LPs) in children are reportedly as low as 50%. In addition to procedural complications and failure, difficult LPs are a risk factor for traumatic LPs (TLPs), which can potentially affect diagnostic utility and alter treatment plans for pediatric oncology patients. To identify the intrinsic factors associated with technically difficult LPs in the pediatric oncology population, we performed a retrospective review of patients who required diagnostic imaging modalities for LP procedures at a single pediatric oncology institution between September 2008 and November 2018. We evaluated data from 64 LPs performed in 33 patients who were referred for image-guided LPs after undergoing technically difficult LPs that were unsuccessful using anatomic landmarks. In these cases, 96.9% of patients had at least one of the following intrinsic factors: body mass index (BMI) ≥ 25, anatomic spinal abnormalities, history of ≥ 5 previous LPs, age < 12 months, and history of back surgery. Elevated BMI was the most common factor associated with difficult LP (81.8%), followed by spinal abnormalities (51.5%), and history of ≥ 5 previous LPs (33.3%). Age < 12 months and history of back surgery were also associated with difficult LPs, but at a lower frequency. On the basis of these findings, we propose clinical recommendations for preprocedural identification of patients at risk of difficult LPs to reduce complications, including TLP, failure, and exposure to general anesthesia.

Safety of fluoroscopically guided pain procedures in patients receiving cytotoxic chemotherapy: a retrospective analysis

PURPOSE

To examine the incidence of bleeding and infectious adverse events (AEs) in patients undergoing interventional, fluoroscopic-guided axial spine procedures to modulate pain.

METHODS

Retrospective data of patients undergoing fluoroscopically guided axial spine injections at a single tertiary care medical center Cancer Rehabilitation program in the USA were reviewed. AEs, type of chemotherapy, type of tumor, age, platelet and absolute neutrophil counts (ANC) prior to the procedure, and relevant past medical history were collected. Descriptive statistical analyses were performed.

RESULTS

Sixty-three separately identifiable procedures across 28 patients met inclusion criteria. Zero AEs were recorded. Platelet and ANC were generally above the recommended safety threshold, but granulocyte colony stimulating factor was administered prior to four procedures to boost ANC levels. Multiple myeloma was the most common cancer diagnosis (64.3%). Various solid tumors made up the remaining cancer diagnoses. Epidural steroid injections (n=23) and medial branch blocks (n=23) were the most common procedures performed and lumbar (n=35) was the most common location of procedures. Three patients died within 30 days of the procedures but their deaths were not directly attributable to the injections.

CONCLUSION

This provides preliminary data to support the safety of injections in patients receiving cytotoxic chemotherapy. Larger, multicenter studies are required before firm conclusions can be drawn.

Safety of bedside lumbar puncture in adult patients with thrombocytopenia

The risk of lumbar puncture (LP) hemorrhagic complications is believed to be exacerbated by thrombocytopenia, yet evaluations in clinical practice are lacking. We conducted a retrospective cohort study to examine the risk of traumatic tap (TT) and significant hemorrhagic complications in thrombocytopenic patients undergoing bedside LP. Two hundred sixty-two adult patients undergoing initial bedside LP were analyzed. Overall, we observed 37 TTs (14.1%, 95% CI 10.0 to 18.3%). TTs occurred in 11 of 78 LPs performed on patients with thrombocytopenia, compared with 26 of 184 LPs among patients with a normal platelet count (14.1% vs 14.1%; p > 0.99) and 6 of 19 LPs among patients with severe thrombocytopenia compared with 31 of 243 among those without (31.6% vs 12.8%; p = 0.04). For patients with severe thrombocytopenia, the relative risk of TT was 2.5 (95% CI 1.2 to 5.2; p = 0.02). Stratifying this group by operator experience, a higher incidence of TTs was observed in LPs performed by trainees (57.1% vs 15.8%; p = 0.02), an effect which did not reach significance in LPs performed by dedicated procedural operators (16.7% vs 10.8%; p = 0.63). The presence of other bleeding risk factors was not found to be statistically associated with the incidence of TT. There were no significant hemorrhagic complications. TTs occurred significantly more frequently among patients with severe thrombocytopenia, an effect modulated by operator experience. For patients in this higher risk group, LPs should be performed by the most skilled operators available.

Acute Bacterial Meningitis

PURPOSE OF REVIEW

While acute bacterial meningitis is becoming less common in developed countries because of the widespread use of vaccines against Streptococcus pneumoniae, Neisseria meningitides, and Haemophilus influenzae, bacterial meningitis still occurs worldwide, with peak incidence in young children and the elderly. Bacterial meningitis is usually lethal unless appropriate antibiotics that cross the blood-brain barrier are given. Clinical suspicion of bacterial meningitis begins when patients present with the abrupt onset of fever, headache, and meningismus.

RECENT FINDINGS

New technologies are being developed for more rapid identification of the bacterial species causing meningitis. When appropriate, administration of adjunctive dexamethasone with the antibiotics often lessens neurologic sequelae in survivors, which may include aphasia, ataxia, paresis, hearing loss, and cognitive impairment.

SUMMARY

Confirmation of the diagnosis of bacterial meningitis comes mainly from examination and culture of CSF obtained from a lumbar puncture. Typically, the CSF shows an elevated neutrophil count, elevated protein, depressed glucose, positive Gram stain, and growth of the bacteria on appropriate culture media. Antibiotic sensitivities of the bacteria determine the appropriate antibiotics, although an educated guess of the best antibiotics to be given promptly must be made until the antibiotic sensitivities return, usually in a few days.

Central Nervous System Bleeding After a Lumbar Puncture: Still an Ongoing Complication

Case series

Patient: Female, 84 • Male, 77

Final Diagnosis: CNS bleeding

Symptoms: Pain • subcutaneous hematomas

Medication: —

Clinical Procedure: Lumbar puncture

Specialty: Neurology

Use of platelet transfusions prior to lumbar punctures or epidural anaesthesia for the prevention of complications in people with thrombocytopenia

BACKGROUND

People with a low platelet count (thrombocytopenia) often require lumbar punctures or an epidural anaesthetic. Lumbar punctures can be diagnostic (haematological malignancies, subarachnoid haematoma, meningitis) or therapeutic (spinal anaesthetic, administration of chemotherapy). Epidural catheters are placed for administration of epidural anaesthetic. Current practice in many countries is to correct thrombocytopenia with platelet transfusions prior to lumbar punctures and epidural anaesthesia, in order to mitigate the risk of serious procedure-related bleeding. However, the platelet count threshold recommended prior to these procedures varies significantly from country to country. This indicates significant uncertainty among clinicians regarding the correct management of these patients. The risk of bleeding appears to be low, but if bleeding occurs it can be very serious (spinal haematoma). Consequently, people may be exposed to the risks of a platelet transfusion without any obvious clinical benefit.This is an update of a Cochrane Review first published in 2016.

OBJECTIVES

To assess the effects of different platelet transfusion thresholds prior to a lumbar puncture or epidural anaesthesia in people with thrombocytopenia (low platelet count).

SEARCH METHODS

We searched for randomised controlled trials (RCTs), non-randomised controlled trials (nRCTs), controlled before-after studies (CBAs), interrupted time series studies (ITSs), and cohort studies in CENTRAL (the Cochrane Library 2018, Issue 1), MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1950), and ongoing trial databases to 13 February 2018.

SELECTION CRITERIA

We included RCTs, nRCTs, CBAs, ITSs, and cohort studies involving transfusions of platelet concentrates, prepared either from individual units of whole blood or by apheresis, and given to prevent bleeding in people of any age with thrombocytopenia requiring insertion of a lumbar puncture needle or epidural catheter.The original review only included RCTs.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane for including RCTs, nRCTs, CBAs, and ITSs. Two review authors independently assessed studies for eligibility and risk of bias and extracted data. Results were only expressed narratively.

MAIN RESULTS

We identified no completed or ongoing RCTs, nRCTs, CBAs, or ITSs. No studies included people undergoing an epidural procedure. No studies compared different platelet count thresholds prior to a procedure.In this update we identified three retrospective cohort studies that contained participants who did and did not receive platelet transfusions prior to lumbar puncture procedures. All three studies were carried out in people with cancer, most of whom had a haematological malignancy. Two studies were in children, and one was in adults.The number of participants receiving platelet transfusions prior to the lumbar puncture procedures was not reported in one study. We therefore only summarised in a narrative form the relevant outcomes from two studies (150 participants; 129 children and 21 adults), in which the number of participants who received the transfusion was given.We judged the overall risk of bias for all reported outcomes for both studies as 'serious' based on the ROBINS-I tool.No procedure-related major bleeding occurred in the two studies that reported this outcome (2 studies, 150 participants, no cases, very low-quality evidence).There was no evidence of a difference in the risk of minor bleeding (traumatic tap) in participants who received platelet transfusions before a lumbar puncture and those who did not receive a platelet transfusion before the procedure (2 studies, 150 participants, very low-quality evidence). One of the 14 adults who received a platelet transfusion experienced minor bleeding (traumatic tap; defined as at least 500 x 10⁶/L red blood cells in the cerebrospinal fluid); none of the seven adults who did not receive a platelet transfusion experienced this event. Ten children experienced minor bleeding (traumatic taps; defined as at least 100 x 10⁶/L red blood cells in the cerebrospinal fluid), six out of the 57 children who received a platelet transfusion and four out of the 72 children who did not receive a platelet transfusion.No serious adverse events occurred in the one study that reported this outcome (1 study, 21 participants, very low-quality evidence).We found no studies that evaluated all-cause mortality within 30 days from the lumbar puncture procedure, length of hospital stay, proportion of participants who received platelet transfusions, or quality of life.

AUTHORS' CONCLUSIONS

We found no evidence from RCTs or non-randomised studies on which to base an assessment of the correct platelet transfusion threshold prior to insertion of a lumbar puncture needle or epidural catheter. There are no ongoing registered RCTs assessing the effects of different platelet transfusion thresholds prior to the insertion of a lumbar puncture or epidural anaesthesia in people with thrombocytopenia. Any future study would need to be very large to detect a difference in the risk of bleeding. A study would need to be designed with at least 47,030 participants to be able to detect an increase in the number of people who had major procedure-related bleeding from 1 in 1000 to 2 in 1000. The use of a central data collection register or routinely collected electronic records (big data) is likely to be the only method to systematically gather data relevant to this population.