Cut the end of the catheter to approximately the length at which it would reach down to one third of the length of the swine's sternum. Using Adson-Brown forceps, grasp the middle of the isolated IJV segment and make a cut halfway through the vessel with curved Metzenbaum scissors. While holding the IJV segment, insert the vein pick into the caudal segment of the vessel.
While maintaining tension on the cranial suture tie. Insert and thread the end of the catheter into the vessel caudally. Once the catheter is fully inserted, knot the caudal suture tie once to temporarily secure the Hickman catheter.
Once patency is confirmed, knot the caudal suture tie twice to secure the distal IJV segment around the intravenous catheter. Then knot the cranial suture tie once to occlude blood flow in the IJV segment. Once done to close the ventral surgical site, first suture platysma simple interrupted sutures with a 3-0 braided absorbable suture.
Then close subcuticular running sutures with a 3-0 monofilament absorbable suture. To secure the Hickman catheter to the animal's skin, orient the Hickman catheter so that it forms a U shape. Then identify three points.
The first point is within two centimeters of the exit site. The second point is over the forked portion of the catheter where the red and white lines diverge. And the third point is at the top of the U between the first two points.
At each point, place a three centimeter piece of one inch medical tape over the catheter to create a wing on each side. With a O synthetic monofilament, non-absorbable polypropylene suture, secure each wing to the skin via a single simple interrupted suture. At the second point over the forked portion, add a single interrupted suture through the gap between the two lines and ensure that the knot lies on top of the tape to prevent irritation.
Test the patency of the white and red lines outside the sterile field via blood draws and flushes using 10 milliliters of 0.9%normal saline and 10 milliliters of heparinized saline. Once the catheter pouch with the desired number of flaps is created, align the hole and flap one with the point where the lines exit the collar, orienting it so that it's opening is caudal. Ensure the pouch is on the midline or slightly lateral to the dorsal neck.
Then pull the red and white lines through the hole and flap one, ensuring the lines lay flat between flaps one and two with flap three facing up. Using a 0 synthetic monofilament, non-absorbable polypropylene suture, secure the pouch to the collar with a simple interrupted suture at each corner and midway along each end. Do not suture through the skin.
In a representative cohort of 32 swine with endpoint ranging from eight to 132 days, 78.13 of Hickman catheters remained patent until the experimental endpoint. Small repairs were required in 9.38%of cases, while rates of removal or replacement before and after 30 days were 9.38%and 12.5%respectively. Reasons for line compromises included displacement, puncture, and internal blockage.
However, timely repair and replacement demonstrated a 100%functional success rate without significant interference with data collection.
