Knotting of a Swan-Ganz Catheter in the Pulmonary Artery

Abstract

To the Editor: Complications resulting from the use of flow directed, balloon-tipped pulmonary artery catheters have been well described.1Swan HJC Ganz W Use of balloon flotation catheters in critically ill patients.Surg Clin North Am. 1975; 55: 501-520Crossref PubMed Scopus (56) Google Scholar, 2Pace NL A critique of flow-directed pulmonary arterial catheterization.Anesthesiology. 1977; 47: 455-465Crossref PubMed Scopus (46) Google Scholar, 3Andreasson S Appelgren LK Complications of the Swan-Ganz catheter.Crit Care Med. 1979; 7: 330-334Crossref PubMed Scopus (2) Google Scholar Among these, intracardiac knotting of the catheter and techniques for knot removal have also been reviewed.4Mond HG Clark DW Nesbitt SJ et al.A technique for unknotting an intracardiac flow-directed balloon catheter.Chest. 1975; 67: 731-732Abstract Full Text Full Text PDF PubMed Scopus (30) Google Scholar, 5Lipp H O’Donoghue K Resnekov L Intracardiac knotting of a flow directed balloon catheter.N Engl J Med. 1971; 284: 220Crossref PubMed Scopus (80) Google Scholar, 6Baldi J Fishenfeld I Benchimol A Complete knotting of a catheter and a nonsurgical method of removal.Chest. 1974; 65: 93-95Crossref PubMed Scopus (17) Google Scholar All of the previously described cases of catheter knotting have involved looping of the catheter in either the right atrium or right ventricle. We recently had a case in which a pulmonary artery catheter was inserted and an adequate pulmonary artery wedge pressure obtained. Central venous, right ventricular and pulmonary artery tracings while introducing the catheter had also been unremarkable. Initial cardiac outputs, however, varied markedly, and were difficult to reproduce. The chest x-ray film revealed the problem (Fig 1). Obvious looping of the catheter in the left pulmonary artery outflow tract had occurred, with knot formation. Despite this, the catheter tip was in adequate position, and wedged easily. The catheter was subsequently removed without complications. Cardiac outputs obtained via thermodilution techniques were inconsistent probably secondary to the artificially reduced distance from the injection port to the thermistor. This was caused by the loop in the catheter, and most likely resulted in inadequate venous mixing of the injectate. To our knowledge, this case represents the first documented report of knotting of a balloon-tipped pulmonary artery catheter in the pulmonary artery. Further, it gives another possible etiology for erroneous cardiac output measurements.