A prospective randomised trial comparing insertion success rate and incidence of catheterisation-related complications for subclavian venous catheterisation using a thin-walled introducer needle or a catheter-over-needle technique

1. Kim, B. G. Kim, Y. J. Lim, Y. T. Jeon, J. W. Hwang, H. C. Kim, Y. H. Choi and H. P. Park

http://dx.doi.org/10.1111/anae.13543

  Gavin Denton and I discuss this piece of research which tries to establish which needle is best for inserting the central venous catheter into the subclavian vein. The results seem fairly clear in this one. I for one am going to be sticking to my current practice. Gavin also kindly broke down the research as a quick summary.

Clinical question.

In patient requiring central venous subclavian catheterisation, does a needle over catheter technique increase the success rate of catheterisation and reduce compilations compared to a needle wire approach.  

Design.

• Two centre.
• Single blinded.
• Randomised (computer randomised).
• Assignment sealed until the day of surgery.
• Data collected by third party who was blinded to assignment.
• Power calculated on a 19% incidence of complications.
• 80% power calculation, a p value 0.05. N=188 per group, to identify 10% difference.
• 10% extra recruited to account for drop out (only two dropped out). N=214.

 

Setting.

Elective neurosurgery.  

Population.

Elective patients in two South Korean hospitals.  

Intervention/control.

• Right subclavian central venous catheterisation.
• Needle guide wire versus needle canula technique.
• Two anaesthetist in each hospital performed all canulations, and all had practiced at least 100 central venous canulations.
• Either landmark or ultrasound technique could be used.
• The landmark technique was clearly described.

 

Outcome.

• Primary outcome (catheter related complications). Needle-wire 5.8% vs 15.5% needle-catheter, p.value 0.001.
• First pass success. Needle-wire 35.4% vs 62% needle-catheter, p.value 0.001
• Overall canulation success, needle-wire 97% vs 92% needle-catheter, p.value 0.046.
• Haemotoma, needle-wire 3.8% vs 10.2% needle-catheter, p.value 0.012.
• Time to canulation, 122 seconds needle-wire vs 101 seconds needle-catheter, p.value 0.002.

 

Author’s conclusion.

Needle-catheter technique causes more complications compared to the needle-wire technique.  

Strengths.

• Single blinded, double blinding would be impossible.
• Experience of clinicians.
• Minimum number of clinicians limit confounding.
• Well powered with minimal dropout.

 

Weaknesses.

• Low BMI in study patients, may limit generalisability to other populations.
• Elective population, may limit generalisability to patients of greater acuity.
• May be under powered to detect differences between techniques when ultrasound is used.
• Does not clearly state if patients were randomised to ultrasound.

 

Bottom line.

 The traditional teaching that needle-catheter central venous subclavian cannulation is easier and has less complications compared to a need wire technique is incorrect and is in fact inferior. Using medcalc and the available figures odds ratio for complications using the needle-catheter is 2.74, absolute risk increase of 8%, and a number needed to harm of 11 assuming a 95% confidence interval.   Links. http://www.ncbi.nlm.nih.gov/pubmed/27396474   [table id=1 /]