Real-time detection of cerebrospinal fluid with bioimpedance needle in paediatric lumbar puncture

Novice providers' success in performing lumbar puncture: a randomized controlled phantom study between a conventional spinal needle and a novel bioimpedance needle

BACKGROUND

Lumbar puncture (LP) is an important yet difficult skill in medical practice. In recent years, the number of LPs in clinical practice has steadily decreased, which reduces residents' clinical exposure and may compromise their skills and attitude towards LP. Our study aims to assess whether the novel bioimpedance needle is of assistance to a novice provider and thus compensates for this emerging knowledge gap.

METHODS

This randomized controlled study, employing a partly blinded design, involved 60 s- and third-year medical students with no prior LP experience. The students were randomly assigned to two groups consisting of 30 students each. They performed LP on an anatomical lumbar model either with the conventional spinal needle or the bioimpedance needle. Success in LP was analysed using the independent samples proportion procedure. Additionally, the usability of the needles was evaluated with pertinent questions.

RESULTS

With the conventional spinal needle, 40% succeeded in performing the LP procedure, whereas with the bioimpedance needle, 90% were successful (p < 0.001). The procedures were successful at the first attempt in 5 (16.7%) and 15 (50%) cases (p = 0.006), respectively. Providers found the bioimpedance needle more useful and felt more confident using it.

CONCLUSIONS

The bioimpedance needle was beneficial in training medical students since it significantly facilitated the novice provider in performing LP on a lumbar phantom. Further research is needed to show whether the observed findings translate into clinical skills and benefits in hospital settings.

A previous champagne tap reduces the probability of traumatic lumbar puncture in the following procedure

A cerebrospinal fluid (CSF) sample containing no red blood cells (RBC), colloquially known as a champagne tap, is an ideal outcome of a lumbar puncture (LP). In this pseudoprospective study of 2573 patients aged from 0 days to 95 years, we examined in four different age categories (neonates and infants, children and adolescents, adults, and older adults) whether a champagne tap in the patient's first LP procedure and a shorter time than 1 week between the two successive procedures are independently associated with fewer blood-contaminated CSF samples (traumatic LP) in the following procedure. One out of five CSF samples from the patient's first LP procedures were RBC-free on average, varying from about 9% in neonates and infants to about 36% in children and adolescents. The mean incidence of champagne taps was 19.5%. According to binary logistic regression, a champagne tap in the previous LP procedure significantly determined whether the following procedure was not blood-contaminated. The odds of traumatic LP were halved or even reduced tenfold after a champagne tap. Less than a week between the two successive procedures, in turn, multiplied the odds of traumatic LP in the latter even more than tenfold. A champagne tap was not significantly associated with traumatic LP in the following procedure among pediatric patients. If the patient's condition or therapy plan permits and the blood contamination can compromise the reliability of the CSF-based analysis and consequent diagnosis, postponing the LP procedure by several days is advisable to improve the odds of receiving a high-quality CSF sample.

Development and evaluation of a robotic system for lumbar puncture and epidural steroid injection

Introduction

Lumbar puncture is an important medical procedure for various diagnostics and therapies, but it can be hazardous due to individual variances in subcutaneous soft tissue, especially in the elderly and obese. Our research describes a novel robot-assisted puncture system that automatically controls and maintains the probe at the target tissue layer through a process of tissue recognition.

Methods

The system comprises a robotic system and a master computer. The robotic system is constructed based on a probe consisting of a pair of concentric electrodes. From the probe, impedance spectroscopy measures bio-impedance signals and transforms them into spectra that are communicated to the master computer. The master computer uses a Bayesian neural network to classify the bio-impedance spectra as corresponding to different soft tissues. By feeding the bio-impedance spectra of unknown tissues into the Bayesian neural network, we can determine their categories. Based on the recognition results, the master computer controls the motion of the robotic system.

Results

The proposed system is demonstrated on a realistic phantom made of ex vivo tissues to simulate the spinal environment. The findings indicate that the technology has the potential to increase the precision and security of lumbar punctures and associated procedures.

Discussion

In addition to lumbar puncture, the robotic system is suitable for related puncture operations such as discography, radiofrequency ablation, facet joint injection, and epidural steroid injection, as long as the required tissue recognition features are available. These operations can only be carried out once the puncture needle and additional instruments reach the target tissue layer, despite their ensuing processes being distinct.

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.

Post-dural puncture headache prevention and treatment with aminophylline or theophylline: a systematic review and meta-analysis

BACKGROUND

Post-dural puncture headache (PDPH) is one of the most common complications in patients undergoing spinal anesthesia. The present systematic review and meta-analysis aimed to assess the therapeutic and prophylactic effects of aminophylline and theophylline on PDPH.

METHODS

Relevant studies were identified by searching the following electronic databases, without language restriction, until June 2020: Scopus, EMBASE, MEDLINE, Google Scholar, Web of Science, Cochrane Library-CENTRAL, and CINAHL Complete. Random effects models were used to calculate the standardized mean difference (SMD) and risk ratios (RRs) with 95% confidence intervals (95% CI) to assess the therapeutic and prophylactic effects of aminophylline and theophylline on PDPH, respectively. The Cochrane tool was used for the quality assessment of the included studies. The certainty of the evidence was rated using the Grading of Recommendations Assessment, Development, and Evaluation method.

RESULTS

Of the 1,349 initial records, 15 met our eligibility criteria (6 studies on therapeutic and 9 on prophylactic effects). A significant reduction in the pain score was observed following aminophylline/theophylline treatment (SMD = -1.67; 95% CI, -2.28 to -1.05; P < 0.001, I2 = 84.7%; P < 0.001). Subgroup analysis revealed that the therapeutic effect was significantly higher when these agents were compared to placebo than when conventional therapies were used. The risk of PDPH after aminophylline administration was not significantly reduced (RR = 0.74; 95% CI, 0.42 to 1.31; P = 0.290).

CONCLUSIONS

Theophylline and aminophylline have therapeutic, but not prophylactic, effects on PDPH.

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.

Humanin vivoliver and tumor bioimpedance measured with biopsy needle

Objective:Liver biopsy is an essential procedure in cancer diagnostics but targeting the biopsy to the actual tumor tissue is challenging. Aim of this study was to evaluate the clinical feasibility of a novel bioimpedance biopsy needle system in liver biopsy and simultaneously to gatherin vivobioimpedance data from human liver and tumor tissues.Approach:We measured human liver and tumor impedance datain vivofrom 26 patients who underwent diagnostic ultrasound-guided liver biopsy. Our novel 18G core biopsy needle tip forms a bipolar electrode that was used to measure bioimpedance during the biopsy in real-time with frequencies from 1 kHz to 349 kHz. The needle tip location was determined by ultrasound. Also, the sampled tissue type was determined histologically.Main results:The bioimpedance values showed substantial variation between individual cases, and liver and tumor data overlapped each other. However, Mann-Whitney U test showed that the median bioimpedance values of liver and tumor tissue are significantly (p<0.05) different concerning the impedance magnitude at frequencies below 25 kHz and the phase angle at frequencies below 3 kHz and above 30 kHz.Significance:This study uniquely employed a real-time bioimpedance biopsy needle in clinical liver biopsies and reported the measured humanin vivoliver and tumor impedance data. Impedance is always device-dependent and therefore not directly comparable to measurements with other devices. Although the variation in tumor types prevented coherent tumor identification, our study provides preliminary evidence that tumor tissue differs from liver tissuein vivoand this association is frequency-dependent.

Aminophylline for Prevention and/or Treatment of Post-Dural Puncture Headache: A Systematic Review and Meta-Analysis Study Protocol

Objectives

Post-dural Puncture Headache (PDPH) is prevalent among individuals undergoing lumbar punctures. The non-invasive effect of some drugs, such as aminophylline on PDPH has been investigated in several clinical studies. As there is no comprehensive systematic review and meta-analysis about the preventive and therapeutic effects of aminophylline on PDPH in the literature, the clinical effectiveness of this drug on the prevention and/or treatment of PDPH will be assessed in this study.

Methods

PubMed/MEDLINE, Embase, WoS (Clarivate Analytics), the Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL Complete, Scopus, and Google Scholar as electronic databases will be precisely searched for clinical studies that assessed the effect of aminophylline on PDPH. Studies between 01-01-1980 and 30-06-2020 will be evaluated in this study, and there will not be any language restrictions. Contradictions between the reviewers within any phase of the study (screening, selecting, quality assessment, and data extraction) will be resolved by consensus; in case of unsolved disagreements, a third reviewer will eventually decide. The combination method will be applied according to the methodological resemblance in the selected articles using the Random Effect Model or the Fixed Effect Model. Also, for the included articles, forest plots will be drawn. For assessing statistical heterogeneity, the I² statistic and the Q-statistic test will be applied. In addition, funnel plots will be used for assessing non-significant study effects and potential reporting bias. Furthermore, Egger’s and Begg’s tests will be done, and publication bias will be indicated by significant findings (P < 0.05).

Conclusions

It is expected that the results of this study will be of benefit to researchers and clinicians for managing PDPH, and will be reported in conferences and publications.

Real-time detection of cerebrospinal fluid with bioimpedance needle in paediatric lumbar puncture

Background

Lumbar puncture is a common clinical procedure that can occasionally be difficult. Various needle guidance methods can facilitate performing this procedure, but at the expense of special expertise, equipment and facility. In the present study, we evaluated the clinical feasibility of a novel bioimpedance needle system regarding its ability to detect cerebrospinal fluid (CSF) in paediatric lumbar punctures.

Methods

We performed 40 lumbar puncture procedures using the bioimpedance needle system in 37 paediatric patients, aged from 0 days to 17 months, as a part of their prescribed examinations in two university hospitals. The bioimpedance needle is similar to a conventional 22G cutting‐edge spinal needle with a stylet, except the needle and stylet are configured as a bipolar electrode with high spatial resolution. The system measures in real‐time when the needle tip reaches the subarachnoid space containing CSF. The procedure was considered successful when the erythrocyte count was determined from the obtained CSF sample.

Results

Subarachnoid space was verifiably reached in 28 out of 40 procedures (70%). Bioimpedance needle system detected CSF in 23 out of these 28 successful procedures (82%) while failed in 3 out of 28 procedures (11%). No adverse events were reported.

Conclusion

Bioimpedance spinal needle system was found clinically feasible in paediatric lumbar punctures, and it may offer an objective and simple means to detect the time point when the needle tip is in contact with the cerebrospinal fluid.