Unusual difficulty during central venous catheterization.

Sir,

Central venous cannulation and its complications are well described entity in anesthesia.[12] Here we have described an unusual problem encountered during negotiation of guidewire into the side port of introducer needle and its solution that was done in this situation.

We received a call for central venous access in a 26-year-old female patient who was a diagnosed case of tubercular meningitis with very poor peripheral venous access. The patient was on synchronized intermittent mandatory ventilatory support. Coagulation parameters of the patient were in normal range. We decided to cannulate right subclavian vein. We located right subclavian vein using introducer needle in first attempt under all aseptic precautions. But surprisingly we could not negotiate guidewire through the side port of introducer needle even on three attempts. We applied a little force and also tried with different orientations of guidewire assembly. We noticed that guidewire was abutting against the wall of the side port due to angulation of wire inside it [Figure 1]. We removed the needle to check the cause of the same. Guidewire assembly was improperly fitted into side port. We decided to shave off the distal ridge of guidewire holding assembly using scalpel blade of kit [Figure 2]. Now, guidewire could be easily introduced into the needle and we threaded central venous catheter (Certofix Trio V720 7Fr) in the right subclavian vein without any difficulty in our second attempt of cannulation.

Figure 1

(a) Improper fitting of guidewire assembly with gap (horizontal line) and abutting wire tip (black arrow) (b) Perfect fitting after distal ridge shaving and no gap (white arrow)

Figure 2

Before (a) and after (b) shaving distal ridge (After shaving distal ridge diameter is reduced. Compare white arrow with black arrow, in (a) black arrow bigger while in (b) same length.)

Subclavian vein cannulation is associated with multiple complications, including arterial puncture, pneumothorax, hemothorax, and hematoma, which are mostly related to introducer needle. Guidewire-related problems include kinking, knotting, looping, and entrapment of wire in filters, sternocleidomastoid muscle, or even subcutaneous tissue.[34] In our case we were not able to introduce guidewire beyond side port of introducer needle as it was impinging on side wall of the side port. On checking we found that due to some minor manufacturing defect, the distal ridge of guidewire-holding assembly was preventing it from fitting properly inside the side port. The improper fit was creating space for guidewire to follow its natural curve (J tip) and that's why instead of going straight into the needle, the guidewire was abutting against the wall of the side port. Shaving distal ridge made it to fit properly and we catheterized the vein successfully.

Although we do not recommend tempering any medical device, in our condition the cause of problem was obvious and free from any ill effects on the patient. We recommend that before inserting introducer needle one should always check compatibility of the guidewire assembly.