Bedside approach to optimizing the positioning of intra-aortic balloon pumps

Abstract

Editor—An intra-aortic balloon pump (IABP) is frequently used to support patients with haemodynamic instability, such as that associated with cardiogenic shock, ischaemic heart disease, postsurgical myocardial dysfunction, or septic shock. The efficacy of IABP therapy depends on the optimal positioning of the tip of the balloon, which should be placed 2−3 cm distal to the origin of the left subclavian artery (LSCA).1Hyson EA Ravin CE Kelley MJ Curtis AM Intraaortic counterpulsation balloon: radiographic considerations.Am J Roentgenol. 1977; 128: 915-918Crossref PubMed Scopus (29) Google Scholar Adequate IABP placement can maximize blood flow through the coronary artery and minimize the risks of both embolization to cerebral vessels and occlusion of the LSCA. Improper positioning of an IABP can cause fatal complications, such as vascular complications and decreased perfusion of vessels of the aortic arch or an affected limb. The aims of the present study were (i) to evaluate whether the distance from the puncture site of the femoral artery (FA) to either the sternal angle (PA) or left second intercostal space at the mid-clavicular line (PI) was a reliable bedside predictor of the correct position for IABP; and (ii) to assess whether the distance from either the puncture site of the FA to the sternal notch (PN) or the sum of distances from the puncture site at the FA to the umbilicus and the distance from the umbilicus to the sternal angle (PUA) may be a better bedside predictor of optimal IABP placement. Values for PA, PI, PN, and PUA were measured before the insertion of the IABP (Fig. 1). For IABP insertion, the right FA was punctured 2 cm below the inguinal crease, after palpating the femoral arterial pulse.2Bregman D Casarella WJ Percutaneous intraaortic balloon pumping: initial clinical experience.Ann Thorac Surg. 1980; 29: 153-155Abstract Full Text PDF PubMed Scopus (74) Google Scholar Insertion of IABP was guided by transoesophageal echocardiography.3Nishioka T Friedman A Cercek B et al.Usefulness of transesophageal echocardiography for positioning the intraaortic balloon pump in the operating room.Am J Cardiol. 1996; 77: 105-106Abstract Full Text PDF PubMed Scopus (12) Google Scholar In general, the tip of the balloon was positioned 2 cm distal to the origin of the LSCA. If the LSCA could not be visualized using transoesophageal echocardiography, the tip of the IABP catheter was placed at the level of the inferior margin of the aortic arch before measuring the distance of insertion of the IABP (L). A total of 101 patients undergoing IABP insertion were studied. The measured values of PA, PI, PN, PUA, and L were 544.6 (26.4), 537.4 (27.5), 574.8 (26.2), 568.9 (30.6), and 571.5 (28.4), respectively. Whereas PA, PI, and PN were all significantly different from L (P<0.05), the difference between PUA and L was not significant (P=0.054). In addition, the t-statistics of PA, PI, PN, and PUA were −18.754, −21.802, 3.014, and −1.953, respectively. This means that either PA or PI is significantly shorter than L, and that PN is longer than L. Of the four anatomic landmarks investigated here, only the PUA successfully predicted the correct IABP position. This suggests that PUA may be a useful bedside predictor for the optimal positioning of IABP in emergency situations. However, our study showed that the PA and PI were statistically different from L. The sternal notch, the superior border of the manubrium at the sternum between the clavicular notches, is used for evaluation of the aortic arch. It can be very easily palpated by the hand. Given that the actual length of PN is longer than the PA or PI, we anticipated that the PN may be a more appropriate bedside predictor of IABP tip positioning because it might reflect the anatomical structure that results when the descending aorta proceeds backward along the lumbar vertebra. To our disappointment, however, the PN was longer than L. In conclusion, both (i) the sum of the distance from the site of puncture of the FA to the umbilicus and (ii) the distance from the umbilicus to the sternal angle may be reliable bedside predictor of correct position for IABP in emergency situations. None declared.