Multiple knotting of a swan-ganz catheter.

Complications derived from pulmonary artery catheter placement are about 3%-17%,1 from the most frequent and mild (carotid puncture, extrasystoles, etc) to the most severe (pulmonary artery rupture, pulmonary infarction, ventricular fibrillation, atrioventricular block, etc), and rare ones, such as intravascular catheter knotting, located preferentially in the right atrium (RA) or right ventricle (RV),1,2 this last being the most recent severe complication seen in our unit. It occurred in a 68 year-old patient undergoing an implant of a mitral valve prosthesis due to a double mitral lesion and plasty of the tricuspid due to moderate reflux. Furthermore, in the preoperative ultrasound showed: dilatation of the left atrium, ventricles of normal size and contractility and pulmonary artery systolic pressure of 45 mmHg. After routine monitoring and anaesthesia induction, a high flow tri-lumen Edwards Lifesciences 9 Fr device was inserted in the internal right jugular vein, through which we placed a pulmonary artery 7.5 Fr catheter, guided by intracavitary pressure curves. We were not able to see the course of the pulmonary artery in spite of introducing the catheter for more than 50 cm. After several collection attempts, we requested that the surgeon guide the catheter, who identified the knot, undid it and placed the catheter correctly. During reanimation we once more ran into the impossibility of following the pulmonary artery curve, added to the difficulty of balloon swelling. In view of the malfunctioning of the pulmonary catheter, we attempted to extract it and found this impossible. Radiographical identification of the knot in the pulmonary artery catheter in the RV (Figure 1) and persistent simultaneous bleeding through the pericardial drainages obliged us to perform a surgical revision. We performed haemostasis of the bleeding point at the level of the sternotomy and a “tobacco pouch” on the RA to extract the catheter (Figure 2). We found a complex knot (3×1.5cm) with 2 loops at 8 cm from the tip. Intracardial lesion was ruled out by postoperative ultrasound. The patient evolved satisfactorily and was discharged from the intensive care unit reanimation 48 hours later. Of the multiple factors that predispose to knotting and ravelling, several were present in our case: female, over 60 years of age, blind placement, heating and softening of the catheter (after several attempts), LETTERS TO THE EDITOR