Pediatric emergency medicine trisk 1085

repetitive stretching is most effective with a solid metal dilator or the curved iris forceps An attempt at catheter placement should be undertaken when the artery remains dilated to a diameter that is greater than that of the catheter for a depth of cm To insert the catheter, hold the distal end near the tip as in Figure 130.8B , part C, and place it in the arterial lumen between the prongs of the forceps that are holding open the artery An alternative method, pictured in Figure 130.8B , part C, shows the inner wall of the vessel held with a 22-gauge needle (bent in the shape of a hook by a hemostat), allowing the vessel to be entered directly Pass the catheter under gentle, constant forward pressure to overcome the resistance encountered at the points where the artery turns (just below the skin surface and where the arteries turn upward toward the iliacs; Fig 130.8A ) Blood should flow readily after the second bend when the internal iliac artery is entered As shown in Figure 130.8B , part D, advance the catheter to the appropriate depth as previously estimated; confirm blood flow at the final point Turn the handle of the stopcock toward the infant Gently tighten and knot the purse string, leaving both ends of the suture long Approximately cm from the knot at the base of the cord, make a square knot and then loop and tie the suture around the catheter to help secure it in place, as shown in Figure 130.8B , part E An alternative is to suture in a purse string circumferentially around the umbilical cord Then tie the knot around the catheter to assist in maintaining it securely Also place tape on the abdominal wall as shown in the figure Verify with an abdominal radiograph that the tip of the catheter lies at the desired level Infuse solutions containing heparin (1 U/mL) unless contraindicated for bleeding diathesis UMBILICAL VEIN CATHETERIZATION Indications To gain vascular access rapidly in a newborn with respiratory failure or cardiovascular collapse Venous catheterization is possible until approximately weeks of age Complications Infection Embolization or thrombosis Vessel perforation Hemorrhage Air embolus Equipment Umbilical tape or 3-0 silk suture on straight or curved needle, antiseptic solution (povidone-iodine), sterile gauze pad, drapes, mask, gown, gloves, small curved hemostat Sterile scalpel and no 11 or 15 blade, iris scissors, 5Fr umbilical catheter threeway stopcock, 10-mL syringe with normal saline, infusing solution Procedure The umbilical vein is preferred for vascular access during neonatal resuscitation because the vessel is readily located and cannulated Catheterizing the umbilical vein is generally much easier than catheterizing the umbilical artery Place the newborn supine and restrain the extremities as necessary The newborn should be under a radiant warmer, and heart rate and pulse oximetry should be monitored throughout the procedure Prepare the equipment Attach a 5Fr umbilical catheter to a three-way stopcock and a saline-filled syringe Prime the catheter with normal saline Wearing mask, gown, and gloves, cleanse the umbilical cord and the abdomen from the xiphoid process to the pubic symphysis with povidone-iodine solution and allow to dry Hold the sterile umbilical catheter over the infant to measure the vertical distance from the lateral aspect of the clavicle to the umbilicus The catheter will be advanced into the vein 60% of this distance, beginning at the skin surface, to avoid direct infusion of medications into the liver At the base of the umbilical cord, loosely tie an umbilical tape or insert 3-0 silk suture around the cord to make a purse string Cut the cord to cm from the abdominal wall Locate the vein orifice (larger with thinner wall compared to the arteries) and remove any visible solid clot with fine forceps