ObjectivesExternal ventricular drain (EVD) dislodgement is common and can lead to significant morbidity and mortality. UK trial data suggests dislodgement as high as 12%. This study aimed to establish the range of methods used nationally and determine the most secure method in a porcine model.DesignSurvey and experimental study.Subjects23 neurosurgical units surveyed. Porcine cadaver experimental model.MethodsSurvey distribution was made through the British Neurosurgical Trainee Research Collaborative. 15 securement methods were tested on the porcine model and peak pull-out force before EVD failure was measured. Failure was defined as catheter displacement 1 cm from the insertion site, catheter fracture or suture fracture.ResultsNationally, five EVD securement methods were in common use. There were considerable differences in peak pull-out force between methods. The most secure methods were a construct consisting of anchoring suture, further multiple sutures around a coil of catheter followed by either a soft (25.85N, 95% CI 24.95 N-26.75N) or hard plastic flange (29.05N, 95% CI 25.69 N-32.41N). Individually, anchoring sutures, soft flanges, VentriFix and staples were least secure, whilst multiple sutures and hard flanges were most secure.ConclusionsAn anchoring suture followed by a coil of catheter and a flange is the most secure method for securing EVDs, withstanding up to 8.2 times the force of a single anchoring suture. It is easily employed and may decrease the likelihood of EVD dislodgement and associated complications.
Experimental study of yarn friction slip and fabric shear deformation in yarn pull-out test
