State-of-the-art of lumbar puncture and its place in the journey of patients with Alzheimer's disease.

Recent advances in developing disease-modifying therapies (DMT) for Alzheimer's disease (AD), and the recognition that AD pathophysiology emerges decades before clinical symptoms, necessitate a paradigm shift of health-care systems toward biomarker-guided early detection, diagnosis, and therapeutic decision-making. Appropriate incorporation of cerebrospinal fluid biomarker analysis in clinical practice is an essential step toward system readiness for accommodating the demand of AD diagnosis and proper use of DMTs-once they become available. However, the use of lumbar puncture (LP) in individuals with suspected neurodegenerative diseases such as AD is inconsistent, and the perception of its utility and safety differs considerably among medical specialties as well as among regions and countries. This review describes the state-of-the-art evidence concerning the safety profile of LP in older adults, discusses the risk factors for LP-associated adverse events, and provides recommendations and an outlook for optimized use and global implementation of LP in individuals with suspected AD.

Lumbar puncture in infants with urinary tract infection: Assessment of infant management in the emergency department.

BACKGROUND: Neonatal bacterial infections must be bacteriologically confirmed from laboratory samples to best adjust antibiotic therapy. Lumbar puncture (LP) has been recommended for infants younger than 1 month with suspected serious bacterial infection (SBI) to manage possible meningitis. However, the incidence of bacterial meningitis associated with other infections and particularly with urinary tract infections (UTIs) is low. Recourse to systematic LP may be less essential if infants have a UTI. We aimed (a) to determine the management and frequency of bacterial meningitis coexisting with a documented diagnosis of UTI in infants aged < 1 month who had an LP, and (b) to evaluate the management of infants in emergency admissions with suspected SBI while assessing antibiotic treatment. METHODS: We conducted a retrospective single-center study from January 2010 to April 2019 including all cases of neonatal bacterial infections, and collected data on the clinical, laboratory, and radiological features. RESULTS: In all, 409 infants were included in the study. Of these, 162 (39.6%) presented with a UTI and eight (2%) had bacterial meningitis. Of the infants diagnosed with UTI, 74.7% had an LP, of whom 34.7% experienced LP complications. No coexistence of UTI and bacterial meningitis was found among infants who had an LP and a documented UTI. CONCLUSION: Although not all infants had an LP and a urine culture at the same time, these results show that bacterial meningitis coexisting with a confirmed UTI diagnosis in infants is rare. Furthermore, LP can be traumatic in some cases and therefore its utility should be assessed according to the clinical context.

Evaluating the cerebrospinal fluid tap test with the Hellström iNPH scale for patients with idiopathic normal pressure hydrocephalus.

BACKGROUND: The cerebrospinal fluid tap test (CSF TT) is used for selecting shunt surgery candidates among patients with idiopathic normal pressure hydrocephalus (iNPH). We aimed to evaluate the predictive value of the CSF TT, by using the Hellström iNPH scale for shunted iNPH patients with a standardized method. METHODS: One hundred and sixteen shunt-operated iNPH patients were retrospectively included in this study. The gait and balance domains in the iNPH scale were used as outcome measures for the CSF TT and the total iNPH scale score as the postoperative outcome. A positive response to CSF TT was defined as a change of ≥ 5 points in the gait domain and ≥ 16 points in the balance domain. Differences between CSF TT responders and non-responders, sensitivity, specificity, positive and negative predictive values, accuracy, and correlations between changes from baseline to post CSF TT and from baseline to the postoperative follow-up, were calculated. RESULTS: In the CSF TT there were 63.8% responders in the gait domain and correspondingly 44.3% in the balance domain. CSF TT responders had a significantly better postoperative outcome in the total scale score (gait P ≤ 0.001, balance P ≤ 0.012) and gait CSF TT responders improved more in gait (P ≤ 0.001) and balance CSF TT responders in balance (P ≤ 0.001). No differences between CSF TT gait or balance responders could be found in neuropsychological or urinary continence assessments postoperatively. The sensitivity and specificity of the CSF TT and the outcome of the total iNPH scale score postoperatively were 68.1% and 52.0% for gait and 47.8% and 68.0% for balance, respectively. CONCLUSIONS: The CSF TT, with the Hellström iNPH scale as the outcome measure, has clear limitations in predicting postoperative results. The gait domain may be used to predict outcomes for gait, but the balance domain is too insensitive.

The effect of needle size on cerebrospinal fluid collection time and post-dural puncture headache: A retrospective cohort study.

OBJECTIVE: The main objective of this study was to compare cerebrospinal fluid (CSF) collection time and patient's discomfort between 20G (a)traumatic and 22G atraumatic needles. BACKGROUND: Risk of post-dural puncture headache (PDPH) is decreased using atraumatic needles. Smaller needles may give lower risk but possibly at the cost of increased CSF collection time (due to lower flow), leading to additional patient's discomfort. METHODS: We performed a retrospective study of lumbar puncture data from a research program on CSF metabolomics and compared traumatic 20G (n = 210) with atraumatic 20G (n = 39) and 22G (n = 105) needles. In this cohort, incidence of PDPH was prospectively registered with other procedure details. Primary outcome was CSF collection time (time to fill the tube). Secondary outcomes were pain and stress scores during procedure, and incidence of PDPH. RESULTS: The time to collect 10 mL of CSF was longer for 22G needles (6.1 minutes; 95% CI 5.8-6.5) than for 20G traumatic (2.2 minutes; 95% CI 2.1-2.2) and 20G atraumatic needles (2.9 minutes; 95% CI 2.8-3.1). There were no differences in pain and stress scores. PDPH was lower for 22G atraumatic needles: odds ratio 0.41 (95% CI 0.25-0.66) versus 20G traumatic needles and 0.53 (95% CI 0.40-0.69) versus 20G atraumatic needles. Absolute PDPH rates were 69/210 (32.9%) for 20G traumatic, 13/39 (33.3%) for 20G atraumatic, and 19/105 (18.1%) for 22G atraumatic needles. CONCLUSIONS: CSF collection time is slightly longer for smaller 22G needles, but this does not lead to more discomfort for the patient.

Determining the Diagnostic Utility of Lumbar Punctures in Computed Tomography Negative Suspected Subarachnoid Hemorrhage: A Systematic Review and Meta-analysis.

BACKGROUND: While headache is a common neurologic symptom, subarachnoid hemorrhage (SAH) is a rare and potentially catastrophic cause of sudden-onset severe headache. The utility of the imaging modalities and interventional procedures are central to the investigation of the causes of headache; however, they are not without their limitations, risks, and complications. METHODS: A meta-analysis in accordance with the Preferred Reporting for Systematic Reviews and Meta-analysis guidelines was conducted searching PubMed, EMBASE, and Google Scholar. Patients investigated for suspected subarachnoid hemorrhage (SAH) with a negative computed tomography (CT) and positive lumbar puncture (LP) and final diagnosis of SAH were included. The sensitivity of LP in the context of a negative CT and vsubsequent imaging confirming the cause of SAH (computed tomography angiography, magnetic resonance angiography, digital subtraction angiography [DSA]) was quantified. The pooled data were analyzed using the DerSimonian-Laid random effects model. RESULTS: Four studies with 2782 patients who presented with headache suspicious for SAH were included with an initial negative CT report and a subsequent LP to rule out SAH. All included studies had an observational prospective cohort design. A combined pooled proportion of 0.383 (0.077, 0.756); 0.086 (0.007, 0.238); and 0.22 (0.04, 0.49) for LP+, DSA+, and DSA/computed tomography angiography+ investigations were estimated with a 95% confidence interval. CONCLUSIONS: The current clinical workflow of an LP after a negative CT head for a patient presenting with a sudden-onset severe headache is observed to have a high enough proportion to warrant its continued use despite the sensitivity of modern CT scanners of ≥97%.

Neonates With Urinary Tract Infection: Is a Lumbar Puncture Always Indicated?

BACKGROUND: Our objectives were to determine the prevalence of and to identify risk factors for coexisting bacterial meningitis (BM) in neonates with urinary tract infection (UTI). METHODS: A cross-sectional study was conducted at pediatric emergency department of a tertiary teaching hospital from 2001 to 2017. Infants <29 days of age with UTI (≥10,000 colony-forming units/mL of a single pathogen from a catheterized specimen in association with positive urinalysis) were included. Definite BM was defined as growth of a single bacterial pathogen from a cerebrospinal fluid (CSF) sample and probable BM as (1) positive blood culture with CSF pleocytosis and treatment consistent with BM or (2) antibiotic pretreatment before lumbar puncture, CSF pleocytosis and treatment consistent with BM. Univariate testing was used to identify possible risk factors associated with BM. Receiver operating characteristics curves were constructed for the laboratory markers associated with BM. RESULTS: Three hundred seventy-one infants were included. Five [1.3%; 95% confidence interval (CI): 0.6%-3.1%] had BM: 4 definite BM and 1 probable BM. Risk factors detected for BM were classified as not being well-appearing and a procalcitonin value ≥0.35 ng/mL [sensitivity of 100% (95% CI: 56.6%-100%) and negative predictive value of 100% (95% CI: 96.1%-100%)]. CONCLUSIONS: Coexisting BM occurs uncommonly in neonates with UTI. Well-appearing neonates with UTI and procalcitonin value <0.35 ng/mL were at very low risk for BM; avoiding routine lumbar puncture in these patients should be considered.

A protocol to reduce self-reported pain scores and adverse events following lumbar punctures in older adults.

OBJECTIVE: Lumbar punctures (LPs) are important for obtaining CSF in neurology studies but are associated with adverse events and feared by many patients. We determined adverse event rates and pain scores in patients prospectively enrolled in two cohort studies who underwent LPs using a standardized protocol and 25 g needle. METHODS: Eight hundred and nine LPs performed in 262 patients age ≥ 60 years in the MADCO-PC and INTUIT studies were analyzed. Medical records were monitored for LP-related adverse events, and patients were queried about subjective complaints. We analyzed adverse event rates, including headaches and pain scores. RESULTS: There were 22 adverse events among 809 LPs performed, a rate of 2.72% (95% CI 1.71-4.09%). Patient hospital stay did not increase due to adverse events. Four patients (0.49%) developed a post-lumbar puncture headache (PLPH). Twelve patients (1.48%) developed nausea, vasovagal responses, or headaches that did not meet PLPH criteria. Six patients (0.74%) reported lower back pain at the LP site not associated with muscular weakness or paresthesia. The median pain score was 1 [0, 3]; the mode was 0 out of 10. CONCLUSIONS: The LP protocol described herein may reduce adverse event rates and improve patient comfort in future studies.

Characteristics of cognitive function evaluation using the Montreal cognitive assessment in a cerebrospinal fluid tap test in patients with idiopathic normal pressure hydrocephalus.

OBJECTIVES: Though the Japanese version of the Montreal Cognitive Assessment (MoCA-J) scores change after a cerebrospinal fluid tap test (CSFTT), their characteristics remain unclear. To compare patient response rate to changes in cognitive function observed in the cerebrospinal fluid tap test, and to determine which group of patients were good responders. PATIENTS AND METHODS: This study included 32 patients who were suspected of having idiopathic normal pressure hydrocephalus (iNPH) between May 2017 and October 2018. Cases were divided into, following a CSFTT, a gait responder group and a non-responder group. Scores of the MoCA-J were compared and examined before, one day after, and one week after the CSFTT. RESULTS: Significant changes in MoCA-J scores were observed 1 day and 1 week after the CSFTT in the gait responder group. The change in scores was larger, and had a larger effect size, one week after the CSFTT. On assessment, MoCA-J sub-items began to show changes in attention and abstract items one day after the CSFTT, and significant changes were noted in attention and abstract items in addition to executive functions and orientation one week after the CSFTT. The degree of cognitive function before the CSFTT was less closely related to the amount of change. Changes in cognitive function can be assessed at each time point after the CSFTT, and changes in cognitive function are measured regardless of the level of cognitive function. CONCLUSION: These results suggest that evaluating patients with the MoCA-J may potentially support a more accurate iNPH diagnosis.

[Assessment of lumbar puncture skills in students, interns and residents attending hospital internship]. / Évaluation des étudiants, internes et résidents sur la pratique de la ponction lombaire au cours des stages hospitaliers.

Although lumbar puncture is recognized as a great contributor to the diagnosis of some neurological diseases, the modalities of learning this procedure are still poorly defined in training programs for students attending their hospital internships. Apprehension related to the lack of experience and the fear of failure accelerates the abandonment of the practice. This study aims to assess lumbar puncture skills in the students at the Faculty of Medicine in Nouakchott as well as their subjective experience of this procedure. We conducted a survey of TCEM and DCEM 4 interns, residents and students in May 2017. An anonymous questionnaire on teaching and lumbar puncture practice was elaborated and completed by 92 participants. Data were analyzed using SPSS 20 software. Out of 105 question sheets, only 92 were workable, reflecting a participation rate of 87.6%. Sixty-seven boys and twenty-five girls participated in the survey. Twelve participants had never performed lumbar puncture, most often because they had low self-esteem. Nearly 10% of students had never learned to do this procedure and 22% had learned it without a supervisor (senior doctor). Lumbar puncture failure rate was 45% among our trainees. Few of them recognized (7.5%) that they had prescribed sedation or local anesthesia to patients before lumbar puncture. Sitting position was much more used than lateral decubitus, but 30% of students reported that they had used both. Lumbar puncture was used to help diagnosis in 69% of cases but in 25% of cases it was performed for diagnostic and therapeutic purpose. Diagnostic indications were dominated by meningitis and meningoencephalitis while normal pressure hydrocephalus was the primary motivation for therapeutic lumbar puncture. Our interns reported that complications mainly included traumatic lumbar puncture followed by headache. Lumbar puncture was mainly performed in the Department of Pediatrics (35%), followed by the Department of Neurology (29%), the Emergency Department (19%) and Internal Medicine (9%). The results of our survey show that lumbar puncture practice is still difficult and risky for many students and that they are not sufficiently prepared for it. The modalities of procedure teaching and learning should be reviewed by supervisors, who could integrate new techniques, such as medical simulation dummies, as in most developed countries.

Effects of stylet-in versus stylet-out collection of cerebrospinal fluid from the cisterna magna on contamination of samples, sample quality, and collection time.

OBJECTIVE: To evaluate safety of stylet-in and stylet-out techniques for collection of CSF from the cisterna magna and to assess whether there were differences between techniques with regard to contamination of samples, sample quality, and efficiency of collection. ANIMALS: 10 adult purpose-bred research Beagles. PROCEDURES: A prospective crossover study was conducted. Preanesthetic physical and neurologic examinations and hematologic analyses were performed. Dogs were anesthetized, and collection of CSF samples from the cisterna magna by use of a stylet-in or stylet-out technique was performed. Two weeks later, samples were collected with the other sample collection technique. Samples of CSF were processed within 1 hour after collection. RESULTS: Cellular debris was detected in higher numbers in stylet-in samples, although this did not affect sample quality. The stylet-out technique was performed more rapidly. No adverse effects were detected for either technique. CONCLUSIONS AND CLINICAL RELEVANCE: Both techniques could be safely performed in healthy anesthetized dogs. The stylet-out technique was performed more rapidly and yielded a sample with less cellular debris. Both techniques can be used in clinical practice to yield CSF samples with good diagnostic quality.

To LP or not to LP? Identifying the Etiology of Pediatric Meningitis.

Introduction of conjugate vaccines against Haemophilus influenzae type b, Streptococcus pneumoniae, and Neisseria meningitidis has led to a substantial reduction in cases of acute bacterial meningitis in countries with high routine childhood immunization coverage. The majority of children hospitalized with meningitis in high-income countries have viral or aseptic meningitis and do not require antibiotic treatment. Cerebrospinal fluid analysis is irreplaceable in appropriately diagnosing and treating bacterial meningitis and avoiding unnecessary antibiotics and prolonged hospitalizations in children with viral meningitis. New diagnostic tests have improved detection of bacterial and viral pathogens in cerebrospinal fluid, underscoring the importance of promptly performing lumbar puncture when meningitis is suspected. This article provides an overview of acute bacterial and viral meningitis in children, focusing on the changing epidemiology, the advantages and limitations of conventional and newer diagnostic methods, and considerations for clinical practice.

Recommendations on the Use of Ultrasound Guidance for Adult Lumbar Puncture: A Position Statement of the Society of Hospital Medicine.

EXECUTIVE SUMMARY: When ultrasound equipment is available, along with providers who are appropriately trained to use it, we recommend that ultrasound guidance should be used for site selection of lumbar puncture to reduce the number of needle insertion attempts and needle redirections and increase the overall procedure success rates, especially in patients who are obese or have difficult-to-palpate landmarks. We recommend that ultrasound should be used to more accurately identify the lumbar spine level than physical examination in both obese and nonobese patients. We suggest using ultrasound for selecting and marking a needle insertion site just before performing lumbar puncture in either a lateral decubitus or sitting position. The patient should remain in the same position after marking the needle insertion site. We recommend that a low-frequency transducer, preferably a curvilinear array transducer, should be used to evaluate the lumbar spine and mark a needle insertion site. A high-frequency linear array transducer may be used in nonobese patients. We recommend that ultrasound should be used to map the lumbar spine, starting at the level of the sacrum and sliding the transducer cephalad, sequentially identifying the lumbar spine interspaces. We recommend that ultrasound should be used in a transverse plane to mark the midline of the lumbar spine and in a longitudinal plane to mark the interspinous spaces. The intersection of these two lines marks the needle insertion site. We recommend that ultrasound should be used during a preprocedural evaluation to measure the distance from the skin surface to the ligamentum flavum from a longitudinal paramedian view to estimate the needle insertion depth and ensure that a spinal needle of adequate length is used. We recommend that novices should undergo simulation-based training, where available, before attempting ultrasound-guided lumbar puncture on actual patients. We recommend that training in ultrasound-guided lumbar puncture should be adapted based on prior ultrasound experience, as learning curves will vary. We recommend that novice providers should be supervised when performing ultrasound-guided lumbar puncture before performing the procedure independently on patients.

Can simulation-based education and precision teaching improve paediatric trainees' behavioural fluency in performing lumbar puncture? A pilot study.

BACKGROUND: Low levels of success in performing lumbar puncture have been observed among paediatric trainees. This study assessed the efficacy of simulation-based education with frequency building and precision teaching for training lumbar puncture to behavioural fluency. METHODS: The intervention group was assessed at baseline, at the final training trial, in the presence of distraction, and a minimum of one month after the cessation of the intervention in order to ascertain whether behavioural fluency in lumbar puncture was obtained. Subsequently, the performance of this intervention group (10 paediatric senior house officers) was compared to the performance of a comparator group of 10 more senior colleagues (paediatric registrars) who had not received the intervention. Retrospective chart audit was utilised to examine performance in the clinical setting. RESULTS: Intervention group participants required a mean of 5 trials to achieve fluency. Performance accuracy was significantly higher in the intervention group than the comparator group. Learning was retained at follow-up and persisted during distraction. Retrospective chart audit revealed no significant difference between the performance of the intervention group and a comparator group, comprised of more senior physicians, in the clinical setting, although the interpretation of these analyses are limited by a low number of lumbar punctures performed in the clinical setting. CONCLUSIONS: The programme of simulation-based education with frequency building and precision teaching delivered produced behavioural fluency in lumbar puncture among paediatric trainees. Following the intervention, the performance of these participants was equivalent to, or greater than, that of senior paediatricians. This study supports the need for further research exploring the effectiveness of simulation-based education with precision teaching to train procedural skills to fluency, and the consideration of how best to explore the impact of these on patient outcomes.

Physicians' and Nurses' Perspectives on the Decision to Perform Lumbar Punctures on Febrile Infants ≤8 Weeks Old.

OBJECTIVES: There is wide variation in the decision of whether to perform lumbar punctures (LPs) on well-appearing febrile infants ≤8 weeks old. Our objectives were to identify factors that influence that decision and the barriers and facilitators to shared decision-making about LP with parents of febrile infants. METHODS: We conducted semistructured interviews with 15 pediatric and general emergency medicine physicians and 8 pediatric emergency medicine nurses at an urban, academic medical center. Through interviews, we assessed physicians' practices and physicians' and nurses' perspectives about communication and decision-making with parents of febrile infants. Two researchers independently reviewed the transcripts, coded the data using the constant comparative method, and identified themes. RESULTS: Five themes emerged for factors that influence physicians' decisions about whether to perform an LP: (1) the age of the infant; (2) the physician's clinical experience; (3) the physician's use of research findings; (4) the physician's values, particularly risk aversion; and (5) the role of the primary care pediatrician. Barriers and facilitators to shared decision-making identified by physicians and by nurses included factors related to their perceptions of parents' understanding and acceptance of risks, parents' emotions, physicians' assessment of whether there is clinical equipoise, and availability of follow-up with the primary care pediatrician. CONCLUSIONS: Differences in physicians' values, use of research findings, and clinical experience likely contribute to decisions of whether to perform an LP on well-appearing febrile infants. Incorporation of parents' preferences through shared decision-making may be indicated, although there are barriers that would need to be overcome.

Why Content and Cognition Matter: Integrating Conceptual Knowledge to Support Simulation-Based Procedural Skills Transfer.

BACKGROUND: Curricular constraints require being selective about the type of content trainees practice in their formal training. Teaching trainees procedural knowledge about "how" to perform steps of a skill along with conceptual knowledge about "why" each step is performed can support skill retention and transfer (i.e., the ability to adapt knowledge to novel problems). However, how best to organize how and why content for procedural skills training is unknown. OBJECTIVES: We examined the impact of different approaches to integrating why and how content on trainees' skill retention and transfer of simulation-based lumbar puncture (LP). DESIGN AND PARTICIPANTS: We randomized medical students (N = 66) to practice LP for 1 h using one of three videos. One video presented only the how content for LP (Procedural Only). Two other videos presented how and why content (e.g., anatomy) in two ways: Integrated in Sequence, with why content followed by how content, or Integrated for Causation, with how and why content integrated throughout. MAIN MEASURES: Pairs of blinded raters scored participants' retention and transfer LP performances on a global rating scale (GRS), and written tests assessed participants' procedural and conceptual knowledge. KEY RESULTS: Simple mediation regression analyses showed that participants receiving an integrated instructional video performed significantly better on transfer through their intervention's positive impact on conceptual knowledge (all p < 0.01). Further, the Integrated for Causation group performed significantly better on transfer than the Integrated in Sequence group (p < 0.01), again mediated by improved conceptual knowledge. We observed no mediation of participants' skill retention (all p > 0.01). CONCLUSIONS: When teaching supports cognitive integration of how and why content, trainees are able to transfer learning to new problems because of their improved conceptual understanding. Instructional designs for procedural skills that integrate how and why content can help educators optimize what trainees learn from each repetition of practice.

Canadian and UK/Ireland practice patterns in lumbar puncture performance in febrile neonates with bronchiolitis.

BACKGROUND: Serious bacterial infections in young infants with bronchiolitis are rare. Febrile infants <1 month old with bronchiolitis often receive a lumbar puncture (LP), despite limited data for this practice and lack of clinical practice guidelines for this population. The primary objective was to investigate practice patterns in performance of LPs in the ED management of febrile infants aged ≤30 days with bronchiolitis. METHODS: A cross-sectional survey of two national paediatric emergency research networks (PediatricEmergency Research Canada (PERC) and the PediatricEmergency Research UK/Ireland (PERUKI)) was conducted January to November 2017 using a modified Dillman technique. The survey was preceded by a clinical vignette describing a well appearing, 21-day-old infant with low-grade fever, respiratory findings typical of bronchiolitis and no perinatal serious bacterial infection (SBI) risk features. RESULTS: The response rate from PERC was 169/250 (68%) and 172/201 (86%) from PERUKI. Nine physicians in training were excluded, leaving 332 eligible participants. Although most physicians believe that neonates with bronchiolitis rarely have meningitis (PERC 141/161 (87.6%); PERUKI 154/171 (90%)) and feel comfortable diagnosing bronchiolitis in this group (PERC 136/161 (84.5%); PERUKI 143/171 (83.6%)), there was significant variation in the proportion who would be likely/very likely to perform an LP (PERC 100/161 (62.1%); PERUKI 15/171 (8.8%)) (p<0.0001). Practice in Canada, <10 years in practice and lack of comfort with diagnosing bronchiolitis represent multivariable predictors of LP; OR 23.7 (95% CI 11.7 to 47.9), 2.3 (95% CI 1.2 to 4.2) and 2.5 (95% CI 1.1 to 5.0), respectively. Rapid knowledge of respiratory syncytial virus positivity would decrease LP probability from 35.4% to 20.2%. CONCLUSION: Estimated probability of performing LPs and other interventions in otherwise healthy febrile neonates with bronchiolitis is highly variable between emergency physicians in Canada and the UK/Ireland. Network, <10 years in ED practice and comfort level with diagnosing bronchiolitis in newborns constitute independent predictors of the likelihood of LP performance.