Strength of continuous spinal catheters.

Several commercially available catheters are currently marketed for continuous intrathecal use. Initial studies using continuous spinal catheters have reported several occurrences of retained fragments after removal of the catheter. Accordingly, we measured the break strength of five commercially available catheters. The TFX/Rusch 28- and 32-gauge continuous spinal catheters required 3.18 and 1.92 lb to break, respectively. The Kendall 28-gauge, the Preferred Medical Products 24-gauge, and the 24-gauge Burron catheters averaged 1.22, 1.97, and 3.55 lb to break, respectively. We also tested a commonly used Burron 20-gauge catheter, which is marketed for epidural use, and found it had an average break strength of 6.35 lb. The tested values obtained for the TFX/Rusch catheters were lower than the break strength values supplied by the manufacturers. The authors conclude that the break strength of spinal catheters is one-third to one-half that found for a typical epidural catheter.