A lumbar puncture is the most common cause of a spinal cerebrospinal fluid (CSF) leak. The most common manifestation is a positional headache within a day or two of the procedure. Can we reduce the risk?
The dura (tough outermost layer of meninges holding CSF in around spinal cord and brain) in the lumbar (lower back) region is intentionally punctured with a spinal needle for various diagnostic and therapeutic reasons.
a) Diagnostic lumbar puncture (LP) is performed to analyze the cerebrospinal fluid and/or to measure the CSF pressure.
b) A lumbar puncture is needed for the injection of contrast into the intrathecal space (where CSF flows around the spinal cord) for a type of spinal imaging known as myelography.
a) Spinal anesthesia involves the placement of a spinal needle thru the dura in order to deliver numbing medications into the intrathecal space for surgical procedures.
b) Administration of medications such as chemotherapy drugs that need to reach the brain.
Most often these holes in the lumbar dura heal over quickly, but in some cases, they do not.
The pain and disability may be rather profound, as we see with all types of spinal CSF leaks. While some patients respond well to one epidural blood patch, often more than one is needed and occasionally an open surgical repair is required. The dollar costs and human suffering costs are high. Clearly, we need to be focusing more effort on PREVENTION or RISK REDUCTION where possible.
Three recent publications focus some attention on this issue.
First, the Cochrane Database of Systematic Reviews published this review in April 2017 looking at how the needle size (gauge) and tip design affects the rate of PDPH. The key findings are bolded below.
Needle gauge and tip designs for preventing post-dural puncture headache (PDPH)
Ingrid Arevalo-Rodriguez, Luis Muñoz, Natalia Godoy-Casasbuenas, Agustín Ciapponi, Jimmy J Arevalo, Sabine Boogaard, Marta Roqué i Figuls
First published: 7 April 2017
Editorial Group: Cochrane Anaesthesia, Critical and Emergency Care Group
Background – Post-dural puncture headache (PDPH) is one of the most common complications of diagnostic and therapeutic lumbar punctures. PDPH is defined as any headache occurring after a lumbar puncture that worsens within 15 minutes of sitting or standing and is relieved within 15 minutes of the patient lying down. Researchers have suggested many types of interventions to help prevent PDPH. It has been suggested that aspects such as needle tip and gauge can be modified to decrease the incidence of PDPH.
Objectives – To assess the effects of needle tip design (traumatic versus atraumatic) and diameter (gauge) on the prevention of PDPH in participants who have undergone dural puncture for diagnostic or therapeutic causes.
Search methods – We searched CENTRAL, MEDLINE, Embase, CINAHL and LILACS, as well as trial registries via the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal in September 2016. We adopted the MEDLINE strategy for searching the other databases. The search terms we used were a combination of thesaurus-based and free-text terms for both interventions (lumbar puncture in neurological, anaesthesia or myelography settings) and headache.
Selection criteria – We included randomized controlled trials (RCTs) conducted in any clinical/research setting where dural puncture had been used in participants of all ages and both genders, which compared different tip designs or diameters for prevention of PDPH
Data collection and analysis – We used the standard methodological procedures expected by Cochrane.
Main results – We included 70 studies in the review; 66 studies with 17,067 participants were included in the quantitative analysis. An additional 18 studies are awaiting classification and 12 are ongoing. Fifteen of the 18 studies awaiting classification mainly correspond to congress summaries published before 2010, in which the available information does not allow the complete evaluation of all their risks of bias and characteristics. Our main outcome was prevention of PDPH, but we also assessed the onset of severe PDPH, headache in general and adverse events. The quality of evidence was moderate for most of the outcomes mainly due to risk of bias issues. For the analysis, we undertook three main comparisons: 1) traumatic needles versus atraumatic needles; 2) larger gauge traumatic needles versus smaller gauge traumatic needles; and 3) larger gauge atraumatic needles versus smaller gauge atraumatic needles. For each main comparison, if data were available, we performed a subgroup analysis evaluating lumbar puncture indication, age and posture.
For the first comparison, the use of traumatic needles showed a higher risk of onset of PDPH compared to atraumatic needles (36 studies, 9378 participants, risk ratio (RR) 2.14, 95% confidence interval (CI) 1.72 to 2.67, I2 = 9%).
In the second comparison of traumatic needles, studies comparing various sizes of large and small gauges showed no significant difference in effects in terms of risk of PDPH, with the exception of one study comparing 26 and 27 gauge needles (one study, 658 participants, RR 6.47, 95% CI 2.55 to 16.43).
In the third comparison of atraumatic needles, studies comparing various sizes of large and small gauges showed no significant difference in effects in terms of risk of PDPH.
We observed no significant difference in the risk of paresthesia, backache, severe PDPH and any headache between traumatic and atraumatic needles. Sensitivity analyses of PDPH results between traumatic and atraumatic needles omitting high risk of bias studies showed similar results regarding the benefit of atraumatic needles in the prevention of PDPH (three studies, RR 2.78, 95% CI 1.26 to 6.15; I2 = 51%).
Authors’ conclusions – There is moderate-quality evidence that atraumatic needles reduce the risk of post-dural puncture headache (PDPH) without increasing adverse events such as paraesthesia or backache. The studies did not report very clearly on aspects related to randomization, such as random sequence generation and allocation concealment, making it difficult to interpret the risk of bias in the included studies. The moderate quality of the evidence for traumatic versus atraumatic needles suggests that further research is likely to have an important impact on our confidence in the estimate of effect.
A second meta-analysis from April 2017 compared the incidence of PDPH with cutting (traumatic) versus pencil-point (atraumatic) needles and also found a much lower risk with the pencil-point needles.
Comparison of cutting and pencil-point spinal needle in spinal anesthesia regarding postdural puncture headache: A meta-analysis.
Xu H1, Liu Y, Song W, Kan S, Liu F, Zhang D, Ning G, Feng S.
Medicine (Baltimore). 2017 Apr;96(14):e6527.
Postdural puncture headache (PDPH), mainly resulting from the loss of cerebral spinal fluid (CSF), is a well-known iatrogenic complication of spinal anesthesia and diagnostic lumbar puncture. Spinal needles have been modified to minimize complications. Modifiable risk factors of PDPH mainly included needle size and needle shape. However, whether the incidence of PDPH is significantly different between cutting-point and pencil-point needles was controversial. Then we did a meta-analysis to assess the incidence of PDPH of cutting spinal needle and pencil-point spinal needle.
We included all randomly designed trials, assessing the clinical outcomes in patients given elective spinal anesthesia or diagnostic lumbar puncture with either cutting or pencil-point spinal needle as eligible studies. All selected studies and the risk of bias of them were assessed by 2 investigators. Clinical outcomes including success rates, frequency of PDPH, reported severe PDPH, and the use of epidural blood patch (EBP) were recorded as primary results. Results were evaluated using risk ratio (RR) with 95% confidence interval (CI) for dichotomous variables. Rev Man software (version 5.3) was used to analyze all appropriate data.
Twenty-five randomized controlled trials (RCTs) were included in our study. The analysis result revealed that pencil-point spinal needle would result in lower rate of PDPH (RR 2.50; 95% CI [1.96, 3.19]; P < 0.00001) and severe PDPH (RR 3.27; 95% CI [2.15, 4.96]; P < 0.00001). Furthermore, EBP was less used in pencil-point spine needle group (RR 3.69; 95% CI [1.96, 6.95]; P < 0.0001). CONCLUSIONS: Current evidence suggests that pencil-point spinal needle was significantly superior compared with cutting spinal needle regarding the frequency of PDPH, PDPH severity, and the use of EBP. In view of this, we recommend the use of pencil-point spinal needle in spinal anesthesia and lumbar puncture. PMID: 28383416
A third article published this month reports on their finding of a lower risk of PDPH when the procedure was done with the patients positioned on their side.
Effectiveness of Lateral Decubitus Position for Preventing Post-Dural Puncture
Headache: A Meta-Analysis.
Zorrilla-Vaca A, Makkar JK.
Pain Physician. 2017 May;20(4):E521-E529.
BACKGROUND: Post-dural puncture headache (PDPH) is a relatively common complication of lumbar punctures for spinal anesthesia or neurologic diagnosis. For many years, a high number of drugs has been evaluated to treat PDPH, yet there is a minority to prevent this complication. The lateral decubitus position instead of sitting position during lumbar puncture has become an interesting approach because of its feasibility and patient satisfaction.
OBJECTIVES: In this meta-analysis we hypothesized that lateral decubitus position is an effective manner to prophylactically reduce the incidence of PDPH.
STUDY DESIGN: This meta-analysis pooled all data published in randomized controlled trials (RCTs) examining the impact of position (sitting versus lateral decubitus) during lumbar puncture and the incidence of PDPH.
SETTINGS: This work was performed at Universidad del Valle, in Cali, Colombia, in collaboration with the Department of Anesthesiology at The Johns Hopkins Hospital.
METHODS: Our group searched in PubMed, EMBASE, Cochrane Library and Google Scholar for relevant RCTs, dating from 1990 to July 2016, that compared the sitting and lateral decubitus position with regards to the incidence of PDPH in adult patients (age > 18 years) undergoing lumbar puncture for spinal anesthesia or neurologic diagnosis.
RESULTS: Literature search identified 7 eligible RCTs (6 on spinal anesthesia and only one on neurologic diagnosis) with 1,101 patients, of which 557 had lumbar punctures in lateral decubitus position and 544 in sitting position. Only 3 (out of 7) RCTs favored the lateral decubitus position to significantly reduce the
PDPH. Meta-analysis showed that the lateral decubitus position was associated with a significant reduction of the incidence of PDPH (risk ratio [RR] = 0.61, 95% confidence interval [CI] = 0.44-0.86, P = 0.004, I2 = 25%, P for heterogeneity = 0.24) compared with the sitting position. Subgroup analysis
showed that lateral decubitus position is also associated with reduction of PDPH in spinal anesthesia (RR = 0.69, 95% CI = 0.50-0.95, I2 = 0%, P for heterogeneity = 0.42). We found no statistically significant association between lateral decubitus position and successful placement of spinal needle at first attempt (RR = 1.00, 95% CI = 0.92-1.09, P = 0.94, I2 = 73%, P for heterogeneity = 0.01). There was no evidence of publication bias in our analyses (Egger’s bias = -0.05, P = 0.96).
LIMITATIONS: The low number of RCTs might be an important limitation on our results.
CONCLUSION: Our results indicate that lateral decubitus position during lumbar puncture seems to be a good alternative for preventing PDPH. Further research should focus on the new prophylactic alternatives to reduce the incidence of PDPH.
We know that there is a lower risk of post-dural puncture headache (PDPH) when:
– the procedure is performed by more experienced clinicians (angle of approach, number of attempts),
– the lateral decubitus (side-lying) position is used rather than sitting upright (prone or face-down not studied in comparison),
– when a less traumatic type of lumbar puncture (LP) needle (pencil-point vs sharp or cutting) is used.
Interestingly, the needle size does not consistently affect the risk of PDPH in reported studies. One study last fall found the risk to be increased with larger cutting needles but not with larger pencil-point needles.
Unfortunately, very few physicians are aware of these simple and inexpensive ways to reduce the risk of PDPH to their patients. Very few hospitals provide pencil-point (atraumatic) spinal needles on their LP trays, despite the evidence that this lowers the risk of PDPH. Until patients and physicians question this practice, we are not likely to see a reduction in the incidence of this common complication. While the pencil-tip needles may not be suitable in all cases, their use rather than cutting needles is a very simple risk reduction strategy.