QUESTION 2: Is the lateral decubitus position best for successful paediatric lumbar puncture?

Incidence of Traumatic Lumbar Punctures in Neonates and Infants

OBJECTIVES

 The objective of this study is to examine factors accounting for the incidence of traumatic lumbar puncture (TLP) in infants younger than 1 year old.

STUDY DESIGN

 Retrospective analysis of cerebrospinal fluid (CSF) data from 1,240 neonatal (≤28 days) and 399 infant lumbar puncture (LP) procedures was conducted. Data from two successive LP procedures were obtained from 108 patients. Logistic regression analysis was used to assess factors accounting for the incidence of TLP in the second LP procedure. The following categorical variables were entered into the model: whether the first procedure was traumatic according to criteria of ≥500 and ≥10,000 erythrocytes/µL, whether the LP procedures were performed within a week, and whether the patient was neonatal at the first procedure.

RESULTS

 The incidences of TLP were 42.9% in neonates and 22.5% in infants for the criterion of ≥500 erythrocytes/µL, and 16.6 and 10.3% for the criterion of ≥10,000 erythrocytes/µL. Compared with a nontraumatic first LP procedure, if the first procedure was traumatic according to the criterion of ≥10,000 erythrocytes/µL, the odds ratio (OR) of TLP in the second procedure was 5.86 (p = 0.006). Compared with a longer time, if the successive procedures were performed within a week, the OR of TLP was 9.06 (p < 0.0001) according to the criteria of ≥500 erythrocytes/µL and 3.34 (p = 0.045) according to the criteria of ≥10,000 erythrocytes/µL. If the patient was neonatal at the first procedure, the OR of TLP at the second puncture was 0.32 (p = 0.031) according to the criterion of ≥500 erythrocytes/µL.

CONCLUSION

 The incidence of TLP in neonates is twice as high as that in infants. Successive LP procedures performed within a week and a highly blood-contaminated CSF sample in the first procedure each multiplied the odds of TLP in the second procedure, whereas being a neonate at the time of the first procedure reduced the odds of TLP.

KEY POINTS

· Traumatic LPs increase diagnostic uncertainty.. · Traumatic LPs are twice as common in neonates as in infants.. · Two LPs performed within a week multiplied the odds of traumatic LP.. · Erythrocyte-based criteria for traumatic LP affect the incidence of TLP..

Techniques to increase lumbar puncture success in newborn babies: the NeoCLEAR RCT

Background

Lumbar puncture is an essential tool for diagnosing meningitis. Neonatal lumbar puncture, although frequently performed, has low success rates (50-60%). Standard technique includes lying infants on their side and removing the stylet 'late', that is, after the needle is thought to have entered the cerebrospinal fluid. Modifications to this technique include holding infants in the sitting position and removing the stylet 'early', that is, following transection of the skin. To the best of our knowledge, modified techniques have not previously been tested in adequately powered trials.

Objectives

The aim of the Neonatal Champagne Lumbar punctures Every time - An RCT (NeoCLEAR) trial was to compare two modifications to standard lumbar puncture technique, that is, use of the lying position rather than the sitting position and of 'early' rather than 'late' stylet removal, in terms of success rates and short-term clinical, resource and safety outcomes.

Methods

This was a multicentre 2 × 2 factorial pragmatic non-blinded randomised controlled trial. Infants requiring lumbar puncture (with a working weight ≥ 1000 g and corrected gestational age from 27+0 to 44+0 weeks), and whose parents provided written consent, were randomised by web-based allocation to lumbar puncture (1) in the sitting or lying position and (2) with early or late stylet removal. The trial was powered to detect a 10% absolute risk difference in the primary outcome, that is, the percentage of infants with a successful lumbar puncture (cerebrospinal fluid containing < 10,000 red cells/mm3). The primary outcome was analysed by modified intention to treat.

Results

Of 1082 infants randomised (sitting with early stylet removal, n = 275; sitting with late stylet removal, n = 271; lying with early stylet removal, n = 274; lying with late stylet removal, n = 262), 1076 were followed up until discharge. Most infants were term born (950/1076, 88.3%) and were aged < 3 days (936/1076, 87.0%) with a working weight > 2.5 kg (971/1076, 90.2%). Baseline characteristics were balanced across groups. In terms of the primary outcome, the sitting position was significantly more successful than lying [346/543 (63.7%) vs. 307/533 (57.6%), adjusted risk ratio 1.10 (95% confidence interval 1.01 to 1.21); p = 0.029; number needed to treat = 16 (95% confidence interval 9 to 134)]. There was no significant difference in the primary outcome between early stylet removal and late stylet removal [338/545 (62.0%) vs. 315/531 (59.3%), adjusted risk ratio 1.04 (95% confidence interval 0.94 to 1.15); p = 0.447]. Resource consumption was similar in all groups, and all techniques were well tolerated and safe.

Limitations

This trial predominantly recruited term-born infants who were < 3 days old, with working weights > 2.5 kg. The impact of practitioners' seniority and previous experience of different lumbar puncture techniques was not investigated. Limited data on resource use were captured, and parent/practitioner preferences were not assessed.

Conclusion

Lumbar puncture success rate was higher with infants in the sitting position but was not affected by timing of stylet removal. Lumbar puncture is a safe, well-tolerated and simple technique without additional cost, and is easily learned and applied. The results support a paradigm shift towards sitting technique as the standard position for neonatal lumbar puncture, especially for term-born infants during the first 3 days of life.

Future work

The superiority of the sitting lumbar puncture technique should be tested in larger populations of premature infants, in those aged > 3 days and outside neonatal care settings. The effect of operators' previous practice and the impact on family experience also require further investigation, alongside in-depth analyses of healthcare resource utilisation. Future studies should also investigate other factors affecting lumbar puncture success, including further modifications to standard technique.

Trial registration

This trial is registered as ISRCTN14040914 and as Integrated Research Application System registration 223737.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 15/188/106) and is published in full in Health Technology Assessment; Vol. 27, No. 33. See the NIHR Funding and Awards website for further award information.

Lumbar puncture position in infants-a systematic review and meta-analysis

To analyze the optimal lumbar puncture position in infants. A systematic review and meta-analysis. Infants (age < 1 year). December 2022 in PubMed, Scopus, and Web of Science. Randomized controlled trials focusing on lumbar puncture positions were included. Other lumbar puncture position than standard lateral decubitus position. First puncture success and overall success rate. Secondary outcome was desaturation during puncture and procedure-related harms. Risk of bias 2.0 assessment was performed. Outcomes are reported as risk ratios (RR) with 95% confidence intervals (CI). We screened 225 abstracts, and six studies were included. Four studies compared sitting position, one study head elevated lateral position, and one study prone position to lateral position. Risk of bias was high in two studies. First puncture success rate in sitting position (RR 1.00, CI: 0.78-1.18; 2 studies) and overall success rate in sitting position were similar to lateral position (RR 0.97, CI: 0.87-1.17; 3 studies). First attempt success rate was higher in elevated lateral position (RR 1.48, CI: 1.14-1.92; 1 study) and in prone position (RR 1.09, CI: 1.00-1.17; 1 study).  Conclusion: Sitting position seems to be equally effective in terms of first attempt and overall success in lumbar puncture than standard lateral position. Elevated lateral position and prone positions had better first attempt success than standard lateral position, but these were assessed only in one study each and thus further studies in these positions are needed.  Trial registration: This review was registered in PROSPERO. ID: CRD42022382953. What is Known: •  Success rate in lumbar puncture has been poor and first attempt success rate has varied between 50 to 80% in literature. •  Optimal lumbar puncture positions for infants have been debated between sitting and lateral decubitus position mostly. What is New: •  This is the first meta-analysis focused on lumbar puncture positions in infants, and it found that sitting position was equal to standard lateral position. • Prone position and head elevated lateral positions had higher first puncture success rates, but these were assessed both only in one study, which creates uncertainty to the finding.

Assessment of infant position and timing of stylet removal to improve lumbar puncture success in neonates (NeoCLEAR): an open-label, 2 × 2 factorial, randomised, controlled trial

BACKGROUND

Newborn infants are the highest-risk age group for bacterial meningitis. Lumbar punctures are therefore frequently performed in neonates, but success rates are low (50-60%). In Neonatal Champagne Lumbar punctures Every time-A Randomised Controlled Trial (NeoCLEAR), we sought to optimise infant lumbar puncture by evaluating two modifications to traditional technique: sitting position versus lying down and early stylet removal (stylet removal after transecting the subcutaneous tissue) versus late stylet removal.

METHODS

NeoCLEAR was an open-label, 2 × 2 factorial, randomised, controlled trial, conducted in 21 UK neonatal and maternity units. Infants requiring lumbar puncture at 27⁺⁰ to 44⁺⁰ weeks corrected gestational age and weighing 1000 g or more were randomly assigned (1:1:1:1) to sitting position and early stylet removal, sitting position and late stylet removal, lying position and early stylet removal, or lying position and late stylet removal using a 24/7, web-based, secure, central randomisation system. Block randomisation was stratified within site by corrected gestational age (27⁺⁰ to 31⁺⁶ weeks, 32⁺⁰ to 36⁺⁶ weeks, 37⁺⁰ to 40⁺⁶ weeks, or 41⁺⁰ to 44⁺⁰ weeks), using variable block sizes of four and eight with equal frequency. Laboratory staff were masked to allocation. The primary outcome was successful first lumbar puncture, defined as obtaining a cerebrospinal fluid sample with a red blood cell count of less than 10 000 cells per μL. The primary and secondary (including safety) outcomes were analysed by the groups to which infants were assigned regardless of deviation from the protocol or allocation received, but with exclusion of infants who were withdrawn before data collection or who did not undergo lumbar puncture (modified intention-to-treat analysis). This study is registered with ISRCTN, ISRCTN14040914.

FINDINGS

Between Aug 3, 2018, and Aug 31, 2020, 1082 infants were randomly assigned to sitting (n=546) or lying (n=536), and early (n=549) or late (n=533) stylet removal. 1076 infants were followed-up until discharge and included in the modified intention-to-treat analysis. 961 (89%) infants were term, and 936 (87%) were younger than 3 days. Successful first lumbar puncture was more frequently observed in sitting than in lying position (346 [63·7%] of 543 vs 307 [57·6%] of 533; adjusted risk ratio 1·10 [95% CI 1·01 to 1·21], p=0·029; number needed to treat=16). Timing of stylet removal had no discernible effect on the primary outcome (338 [62·0%] of 545 infants in the early stylet removal group and 315 [59·3%] of 531 in the late stylet removal group had a successful first lumbar puncture; adjusted risk ratio 1·04 [95% CI 0·94-1·15], p=0·45). Sitting was associated with fewer desaturations than was lying (median lowest oxygen saturations during first lumbar puncture 93% [IQR 89-96] vs 90% [85-94]; median difference 3·0% [2·1-3·9], p<0·0001). One infant from the sitting plus late stylet removal group developed a scrotal haematoma 2 days after lumbar puncture, which was deemed to be possibly related to lumbar puncture.

INTERPRETATION

NeoCLEAR is the largest trial investigating paediatric lumbar puncture so far. Success rates were improved when sitting rather than lying. Sitting lumbar puncture is safe, cost neutral, and well tolerated. We predominantly recruited term neonates younger than 3 days; other populations warrant further study. Neonatal lumbar puncture is commonly performed worldwide; these results therefore strongly support the widespread adoption of sitting technique for neonatal lumbar puncture.

FUNDING

UK National Institute for Health and Care Research.

Study protocol: NeoCLEAR: Neonatal Champagne Lumbar punctures Every time - An RCT: a multicentre, randomised controlled 2 × 2 factorial trial to investigate techniques to increase lumbar puncture success

Background

The neonatal period carries the highest risk of bacterial meningitis (~ 1 in 5000 births), bearing high mortality (~ 10%) and morbidity (20–50%) rates. Lumbar puncture (LP) remains essential to the diagnosis of meningitis. Though LP is a common procedure in neonates, success rates are lower (50–60%) than in other patient populations. None of the currently-practised neonatal LP techniques are supported by evidence from adequately-powered, randomised controlled trials (RCTs). NeoCLEAR aims to compare two modifications to the traditional technique which are free, accessible, and commonly practised: sitting (as opposed to lying) position, and ‘early’ (as opposed to ‘late’) stylet removal.

Methods/design

Written parental informed consent permitting, infants in neonatal/maternity wards, of 27^+ 0 to 44^+ 0 weeks corrected gestational age and weighing ≥1000 g, who require an LP, will be randomly allocated to sitting or lying position, and to early or late stylet removal. The co-primary objectives are to compare success rates (the proportion of infants with cerebrospinal fluid red cell count < 10,000/mm³ on first LP procedure) in 1020 infants between the two positions, and between the two methods of stylet removal. Secondary outcomes relate to LP procedures, complications, diagnoses of meningitis, duration of antibiotics and hospital stay. A modified intention-to-treat analysis will be conducted.

Discussion

Two modifications to the traditional LP technique (sitting vs lying position; and early vs late stylet removal) will be simultaneously investigated in an efficient and appropriately-powered 2 × 2 factorial RCT design. Analysis will identify the optimal techniques (in terms of obtaining easily-interpretable cerebrospinal fluid), as well as the impact on infants, parents and healthcare systems whilst providing robust safety data. Using a pragmatic RCT design, all practitioners will be trained in all LP techniques, but there will inevitably be variation between unit practice guidelines and other aspects of individual care.

An improved LP technique would result in:

• Fewer uninterpretable samples, repeated attempts and procedures

• Reduced distress for infants and families

• Decreased antibiotic use and risk of antibiotic resistance

• Reduced healthcare costs due to fewer procedures, reduced length of stay, shorter antibiotic courses, and minimised antibiotic-associated complications

Trial registration

ISRCTN14040914. Date assigned: 26/06/2018.