Neurol Sci (2014) 35:1997–1999 DOI 10.1007/s10072-014-1924-0
BRIEF COMMUNICATION
Are atraumatic spinal needles as efficient as traumatic needles for lumbar puncture? N. Pelzer • J. Vandersteene • T. J. S. Bekooij • G. G. Schoonman • P. W. Wirtz • L. J. Vanopdenbosch H. Koppen
•
Received: 6 May 2014 / Accepted: 6 August 2014 / Published online: 20 August 2014 Ó Springer-Verlag Italia 2014
Abstract The most frequent complication of lumbar puncture is post lumbar puncture headache (PLPH). Recent studies confirmed that the use of atraumatic spinal needles significantly reduces the risk of PLPH. However, the majority of neurologists still use traumatic needles, possibly caused by misconceptions and beliefs about practical performance of atraumatic spinal needles. Therefore, we investigated the practical characteristics of atraumatic and traumatic spinal needles. An experimental setup with a fluid column was used with (1) a physiological NaCl 0.9 % solution and (2) a high protein content solution. Flow rates and duration of pressure measurements were measured using a traumatic needle and an atraumatic needle. The average flow rate differed less than 10 % between the two needle types with NaCl solution, and for the high protein solution the difference was even smaller. Time taken to perform accurate pressure measurements did not differ between the two needle types using NaCl 0.9 %, and was even slightly shorter for the atraumatic needle when using the high protein solution. Average flow rates and duration of N. Pelzer and J. Vandersteene share first authorship. N. Pelzer G. G. Schoonman Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands J. Vandersteene L. J. Vanopdenbosch Department of Neurology, AZ Sint Jan Brugge, Brugge, Belgium T. J. S. Bekooij P. W. Wirtz H. Koppen (&) Department of Neurology, Haga Hospital, Hagaziekenhuis, po box 40551, 2504 LN The Hague, The Netherlands e-mail: [email protected] G. G. Schoonman Department of Neurology, Elisabeth/Twee Steden Ziekenhuis, Tilburg, The Netherlands
pressure measurements are comparable between atraumatic spinal needles and traumatic needles. Therefore, these performance characteristics are no reason to favor traumatic needles over atraumatic needles. Keywords Atraumatic spinal needles Lumbar puncture Post lumbar puncture headache Pressure measurement Traumatic spinal needles
Introduction The most frequent complication of lumbar puncture is post lumbar puncture headache (PLPH). Several factors increase the risk of PLPH, such as young age, female gender or a low body mass index [1]. In general, two types of spinal needles can be used for diagnostic lumbar puncture: traumatic needles or atraumatic needles (of either 20 gauge (G) or 22G, with respective diameters of 0.9 and 0.7 mm). The traumatic type has a sharp cutting tip. The atraumatic pencil-point types (Sprotte, Whitacre) have a smaller, rounded, cone-shaped tip. (Fig. 1) Several studies demonstrated a lower incidence of PLPH with 22G atraumatic needles [2–4]. Persistent leakage of cerebrospinal fluid (CSF) through the puncture hole in the dura is thought to cause PLPH. In vitro studies revealed that atraumatic needles puncture a smaller hole in cadaver dura [5]. A double-blind, controlled trial with 100 patients showed a dramatic reduction of PLPH from over 30 % with the 20G traumatic needle to only 4 % with the 22G atraumatic needle [2]. In a retrospective analysis of 505 patients, 30 % needed a blood patch after lumbar puncture with the old needle compared to only 4 % using the new needle [4]. A recent study confirmed that the use of atraumatic needles significantly reduces the risk of PLPH [6].
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Neurol Sci (2014) 35:1997–1999
Fig. 1 Traumatic needle with sharp cutting tip (up) and an atraumatic needle pencil-point type (down)
Despite this evidence, the majority of neurologists still use traumatic needles [7]. Are differences in practical characteristics between atraumatic and traumatic spinal needles a cause of this practice? Comparative studies on flow rates and pressure measurement using traumatic and atraumatic needles are lacking. Therefore, we investigated if atraumatic spinal needles have the same performance characteristics (reliable measurement of intrathecal pressure and flow rates) compared with traumatic needles.
Fig. 2 Experimental setup with a fluid column of 2 l. The fluid pressure was measured by a Dyna-opt, Gobuplast device similar as used in clinical practice
Table 1 Flow rates and time taken to accurate pressure measurement Spinal needle type
Flow rate (ml/min)
Time taken for accurate pressure measurement (s)
NaCl 0.9 %
Gluc/ Alb
NaCl 0.9 %
Gluc/ Alb
Traumatic 20G
2.2
2.0
7.0
8.8
Atraumatic 22G
2.0
1.9
7.3
7.5
Methods Flow rates were measured using an experimental setup with a fluid column of 2 l (Fig. 2). First, a physiological NaCl 0.9 % solution with viscosity equal to normal CSF was used and, second, a high protein content solution (glucose 0.6 mg/dl ? albumin 10 mg/dl) which has a higher viscosity to simulate an infectious or oncologic state of CSF. Both needle types were used: a traumatic 20G needle and an atraumatic 22G needle. The gauge numbers reflect the needles’ outer diameter, while the inner diameter of the traumatic 20G and the atraumatic 22G are virtually similar. All needles were inserted via a pre-drilled hole in the fluid container to avoid damage to the needle tip. The fluid pressure was measured by a device that is used in clinical practice (Dyna-opt, Gobuplast) and in all cases its value was 11.5 cm H2O (see Fig. 2). To measure flow rates in milliliters per minute, we used a stopwatch (Casio, HS3V-1R, Japan) and measured the time needed for ±50 mL to pass through the needles. The exact amount of passed fluid was weighed and the container was refilled to the original level for each new measurement. All experiments
123
Flow rates and time taken for accurate pressure measurement with a 20G traumatic spinal needle and an 22G atraumatic spinal needle for both a physiological NaCl 0.9 % solution and a high protein content solution (glucose 0.6 mg/dl ? albumin 10 mg/dl)
were done by the same investigator and the measurements were performed with two copies of each type needle and repeated twice, and next the mean value for each type of needle was calculated.
Results The average flow rate differed less than 10 % between the two needle types when using NaCl solution (Table 1). Using the high protein solution (with higher viscosity) the difference was even smaller. Time taken to perform an
Neurol Sci (2014) 35:1997–1999
accurate pressure measurement of 11.5 cm H2O did not differ between the atraumatic and the traumatic needle using NaCl 0.9 %. When using the high protein solution, accurate pressure measurement time for the atraumatic needle was even slightly shorter (7.5 vs. 8.8 s; Table 1).
Discussion The main findings of this study are that: (1) the flow rate of atraumatic 22G spinal needles is comparable with traumatic 20G needles; and (2) the time taken for accurate pressure measurement is also comparable between these two needle types. It is concluded that these performance characteristics do not support a favor of 20G traumatic needles over 22G atraumatic needles. We acknowledge the fact that atraumatic 22G needles are quite blunt and more flexible because of a thinner wall. Therefore, a sharp introducer is often used which requires some habituation. A study using atraumatic needles, however, reported a success rate of 95 % at first attempt [3]. Moreover, anesthesiologists have switched to atraumatic spinal needles worldwide with excellent results. The dramatic reduction in PLPH with atraumatic needles also reduces the total medical costs [8, 9]. Departments may hesitate to purchase atraumatic needles because the material costs of an atraumatic needle (USD 20) are higher than those of a traumatic needle (USD 9). However, in the long term, a reduction of medical and societal costs (less absence from work) makes the atraumatic needle less expensive than the traumatic needle [8, 9]. Physicians may doubt whether the thin atraumatic needles can be used to administer intrathecal chemotherapeutics. Guidelines for administering intrathecal chemotherapy do not specify the preferred spinal needle type, and comparative studies have not been performed. Because the needles are made of the same materials and flow rates are comparable, there are no reasons to believe why atraumatic needles would not be suited for this purpose. In conclusion, results from previous studies and our study should banish all doubts about 22G atraumatic needles. The main barrier that needs to be broken, however, is
1999
the fact that neurologists appear to prefer the needle type that they are used to. To reach this goal, it is important to stress the significant benefit of a lower incidence of PLPH with 22G atraumatic needles and to contradict the possible wrongly assumed disadvantages of atraumatic needles. Conflict of interest Dr. Pelzer reports support for conference visits from Menarini and Allergan UK. T. J. S. Bekooij reports no disclosures. Dr. Vandersteene reports no disclosures. Dr. Schoonman reports no disclosures. Dr. Wirtz reports no disclosures. Dr. Vanopdenbosch reports consultancy and travel support from Teva, Biogen, Novartis, Merck Serono, UCB, Sanofi, Genzyme. Dr. Koppen reports consultancy or travel support from Allergan, Pfizer and Menarini.
References 1. Kuntz KM, Kokmen E, Stevens JC, Miller P, Offord KP, Ho MM (1992) Post-lumbar puncture headaches: experience in 501 consecutive procedures. Neurology 42(10):1884–1887 2. Kleyweg RP, Hertzberger LI, Carbaat PA (1998) Significant reduction in post-lumbar puncture headache using an atraumatic needle. A double-blind, controlled clinical trial. Cephalalgia 18(9):635–637 3. Hammond ER, Wang Z, Bhulani N et al (2011) Needle type and the risk of post-lumbar puncture headache in the outpatient neurology clinic. J Neurol Sci 306(1):24–28 4. Hatfield MK, Handrich SJ, Willis JA et al (2008) Blood patch rates after lumbar puncture with Whitacre versus Quincke 22-and 20-gauge spinal needles. Am J Roentgenol 190(6):1686–1689 5. Enk D, Enk E (1995) A new two-chamber model for examination and demonstration of transdural fluid leakage after spinal anesthesia. Anaesthesist 44(11):761–769 6. Davis A, Dobson R, Kaninia S et al (2014) Change practice now! Using atraumatic needles to prevent post lumbar puncture headache. Eur J Neurol 21:305–311 7. Birnbach DJ, Kuroda MM, Sternman D et al (2001) Use of atraumatic spinal needles among neurologists in the United States. Headache 41(4):385–390 8. Dakka Y, Warra N, Albadareen RJ et al (2011) Headache rate and cost of care following lumbar puncture at a single tertiary care hospital. Neurology 77(1):71–74 9. Tung CE, So YT, Lansberg MG (2012) Cost comparison between the atraumatic and cutting lumbar puncture needles. Neurology 78(2):109–113
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BRIEF COMMUNICATION
Are atraumatic spinal needles as efficient as traumatic needles for lumbar puncture? N. Pelzer • J. Vandersteene • T. J. S. Bekooij • G. G. Schoonman • P. W. Wirtz • L. J. Vanopdenbosch H. Koppen
•
Received: 6 May 2014 / Accepted: 6 August 2014 / Published online: 20 August 2014 Ó Springer-Verlag Italia 2014
Abstract The most frequent complication of lumbar puncture is post lumbar puncture headache (PLPH). Recent studies confirmed that the use of atraumatic spinal needles significantly reduces the risk of PLPH. However, the majority of neurologists still use traumatic needles, possibly caused by misconceptions and beliefs about practical performance of atraumatic spinal needles. Therefore, we investigated the practical characteristics of atraumatic and traumatic spinal needles. An experimental setup with a fluid column was used with (1) a physiological NaCl 0.9 % solution and (2) a high protein content solution. Flow rates and duration of pressure measurements were measured using a traumatic needle and an atraumatic needle. The average flow rate differed less than 10 % between the two needle types with NaCl solution, and for the high protein solution the difference was even smaller. Time taken to perform accurate pressure measurements did not differ between the two needle types using NaCl 0.9 %, and was even slightly shorter for the atraumatic needle when using the high protein solution. Average flow rates and duration of N. Pelzer and J. Vandersteene share first authorship. N. Pelzer G. G. Schoonman Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands J. Vandersteene L. J. Vanopdenbosch Department of Neurology, AZ Sint Jan Brugge, Brugge, Belgium T. J. S. Bekooij P. W. Wirtz H. Koppen (&) Department of Neurology, Haga Hospital, Hagaziekenhuis, po box 40551, 2504 LN The Hague, The Netherlands e-mail: [email protected] G. G. Schoonman Department of Neurology, Elisabeth/Twee Steden Ziekenhuis, Tilburg, The Netherlands
pressure measurements are comparable between atraumatic spinal needles and traumatic needles. Therefore, these performance characteristics are no reason to favor traumatic needles over atraumatic needles. Keywords Atraumatic spinal needles Lumbar puncture Post lumbar puncture headache Pressure measurement Traumatic spinal needles
Introduction The most frequent complication of lumbar puncture is post lumbar puncture headache (PLPH). Several factors increase the risk of PLPH, such as young age, female gender or a low body mass index [1]. In general, two types of spinal needles can be used for diagnostic lumbar puncture: traumatic needles or atraumatic needles (of either 20 gauge (G) or 22G, with respective diameters of 0.9 and 0.7 mm). The traumatic type has a sharp cutting tip. The atraumatic pencil-point types (Sprotte, Whitacre) have a smaller, rounded, cone-shaped tip. (Fig. 1) Several studies demonstrated a lower incidence of PLPH with 22G atraumatic needles [2–4]. Persistent leakage of cerebrospinal fluid (CSF) through the puncture hole in the dura is thought to cause PLPH. In vitro studies revealed that atraumatic needles puncture a smaller hole in cadaver dura [5]. A double-blind, controlled trial with 100 patients showed a dramatic reduction of PLPH from over 30 % with the 20G traumatic needle to only 4 % with the 22G atraumatic needle [2]. In a retrospective analysis of 505 patients, 30 % needed a blood patch after lumbar puncture with the old needle compared to only 4 % using the new needle [4]. A recent study confirmed that the use of atraumatic needles significantly reduces the risk of PLPH [6].
123
1998
Neurol Sci (2014) 35:1997–1999
Fig. 1 Traumatic needle with sharp cutting tip (up) and an atraumatic needle pencil-point type (down)
Despite this evidence, the majority of neurologists still use traumatic needles [7]. Are differences in practical characteristics between atraumatic and traumatic spinal needles a cause of this practice? Comparative studies on flow rates and pressure measurement using traumatic and atraumatic needles are lacking. Therefore, we investigated if atraumatic spinal needles have the same performance characteristics (reliable measurement of intrathecal pressure and flow rates) compared with traumatic needles.
Fig. 2 Experimental setup with a fluid column of 2 l. The fluid pressure was measured by a Dyna-opt, Gobuplast device similar as used in clinical practice
Table 1 Flow rates and time taken to accurate pressure measurement Spinal needle type
Flow rate (ml/min)
Time taken for accurate pressure measurement (s)
NaCl 0.9 %
Gluc/ Alb
NaCl 0.9 %
Gluc/ Alb
Traumatic 20G
2.2
2.0
7.0
8.8
Atraumatic 22G
2.0
1.9
7.3
7.5
Methods Flow rates were measured using an experimental setup with a fluid column of 2 l (Fig. 2). First, a physiological NaCl 0.9 % solution with viscosity equal to normal CSF was used and, second, a high protein content solution (glucose 0.6 mg/dl ? albumin 10 mg/dl) which has a higher viscosity to simulate an infectious or oncologic state of CSF. Both needle types were used: a traumatic 20G needle and an atraumatic 22G needle. The gauge numbers reflect the needles’ outer diameter, while the inner diameter of the traumatic 20G and the atraumatic 22G are virtually similar. All needles were inserted via a pre-drilled hole in the fluid container to avoid damage to the needle tip. The fluid pressure was measured by a device that is used in clinical practice (Dyna-opt, Gobuplast) and in all cases its value was 11.5 cm H2O (see Fig. 2). To measure flow rates in milliliters per minute, we used a stopwatch (Casio, HS3V-1R, Japan) and measured the time needed for ±50 mL to pass through the needles. The exact amount of passed fluid was weighed and the container was refilled to the original level for each new measurement. All experiments
123
Flow rates and time taken for accurate pressure measurement with a 20G traumatic spinal needle and an 22G atraumatic spinal needle for both a physiological NaCl 0.9 % solution and a high protein content solution (glucose 0.6 mg/dl ? albumin 10 mg/dl)
were done by the same investigator and the measurements were performed with two copies of each type needle and repeated twice, and next the mean value for each type of needle was calculated.
Results The average flow rate differed less than 10 % between the two needle types when using NaCl solution (Table 1). Using the high protein solution (with higher viscosity) the difference was even smaller. Time taken to perform an
Neurol Sci (2014) 35:1997–1999
accurate pressure measurement of 11.5 cm H2O did not differ between the atraumatic and the traumatic needle using NaCl 0.9 %. When using the high protein solution, accurate pressure measurement time for the atraumatic needle was even slightly shorter (7.5 vs. 8.8 s; Table 1).
Discussion The main findings of this study are that: (1) the flow rate of atraumatic 22G spinal needles is comparable with traumatic 20G needles; and (2) the time taken for accurate pressure measurement is also comparable between these two needle types. It is concluded that these performance characteristics do not support a favor of 20G traumatic needles over 22G atraumatic needles. We acknowledge the fact that atraumatic 22G needles are quite blunt and more flexible because of a thinner wall. Therefore, a sharp introducer is often used which requires some habituation. A study using atraumatic needles, however, reported a success rate of 95 % at first attempt [3]. Moreover, anesthesiologists have switched to atraumatic spinal needles worldwide with excellent results. The dramatic reduction in PLPH with atraumatic needles also reduces the total medical costs [8, 9]. Departments may hesitate to purchase atraumatic needles because the material costs of an atraumatic needle (USD 20) are higher than those of a traumatic needle (USD 9). However, in the long term, a reduction of medical and societal costs (less absence from work) makes the atraumatic needle less expensive than the traumatic needle [8, 9]. Physicians may doubt whether the thin atraumatic needles can be used to administer intrathecal chemotherapeutics. Guidelines for administering intrathecal chemotherapy do not specify the preferred spinal needle type, and comparative studies have not been performed. Because the needles are made of the same materials and flow rates are comparable, there are no reasons to believe why atraumatic needles would not be suited for this purpose. In conclusion, results from previous studies and our study should banish all doubts about 22G atraumatic needles. The main barrier that needs to be broken, however, is
1999
the fact that neurologists appear to prefer the needle type that they are used to. To reach this goal, it is important to stress the significant benefit of a lower incidence of PLPH with 22G atraumatic needles and to contradict the possible wrongly assumed disadvantages of atraumatic needles. Conflict of interest Dr. Pelzer reports support for conference visits from Menarini and Allergan UK. T. J. S. Bekooij reports no disclosures. Dr. Vandersteene reports no disclosures. Dr. Schoonman reports no disclosures. Dr. Wirtz reports no disclosures. Dr. Vanopdenbosch reports consultancy and travel support from Teva, Biogen, Novartis, Merck Serono, UCB, Sanofi, Genzyme. Dr. Koppen reports consultancy or travel support from Allergan, Pfizer and Menarini.
References 1. Kuntz KM, Kokmen E, Stevens JC, Miller P, Offord KP, Ho MM (1992) Post-lumbar puncture headaches: experience in 501 consecutive procedures. Neurology 42(10):1884–1887 2. Kleyweg RP, Hertzberger LI, Carbaat PA (1998) Significant reduction in post-lumbar puncture headache using an atraumatic needle. A double-blind, controlled clinical trial. Cephalalgia 18(9):635–637 3. Hammond ER, Wang Z, Bhulani N et al (2011) Needle type and the risk of post-lumbar puncture headache in the outpatient neurology clinic. J Neurol Sci 306(1):24–28 4. Hatfield MK, Handrich SJ, Willis JA et al (2008) Blood patch rates after lumbar puncture with Whitacre versus Quincke 22-and 20-gauge spinal needles. Am J Roentgenol 190(6):1686–1689 5. Enk D, Enk E (1995) A new two-chamber model for examination and demonstration of transdural fluid leakage after spinal anesthesia. Anaesthesist 44(11):761–769 6. Davis A, Dobson R, Kaninia S et al (2014) Change practice now! Using atraumatic needles to prevent post lumbar puncture headache. Eur J Neurol 21:305–311 7. Birnbach DJ, Kuroda MM, Sternman D et al (2001) Use of atraumatic spinal needles among neurologists in the United States. Headache 41(4):385–390 8. Dakka Y, Warra N, Albadareen RJ et al (2011) Headache rate and cost of care following lumbar puncture at a single tertiary care hospital. Neurology 77(1):71–74 9. Tung CE, So YT, Lansberg MG (2012) Cost comparison between the atraumatic and cutting lumbar puncture needles. Neurology 78(2):109–113
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