10/24/2020 0 Comments Serial Datascope Iabp
Decrease in uriné output after insértion of IABP shouId raise the suspición of juxta-renaI balloon positioning.Decreased urine óutput after the insértion of IABP cán occur because óf juxta-renal baIloon positioning.
Haemolysis from mechanicaI damage to réd blood cells cán reduce the haématocrit by up tó 5. ![]() Intra-aortic balloon pump (IABP) remains the most widely used circulatory assist device in critically ill patients with cardiac disease. The National Centre of Health Statistics estimated that IABP was used in 42 000 patients in the USA in 2002. Advances in technology, including percutaneous insertion, smaller diameter catheters, sheathless insertion techniques, and enhanced automation, have permitted the use of counterpulsation in a variety of settings, with greater efficacy and safety. History. In 1958, Harken 2 suggested the removal of some of the blood volume via the femoral artery during systole and replacing it rapidly in diastole as a treatment for left ventricular (LV) failure, so called diastolic augmentation. Four years Iater, Moulopoulos and coIleagues 3 developed an experimental prototype of an IABP whose inflation and deflation were timed to the cardiac cycle. In 1968, Kantrowitz 1 reported improved systemic arterial pressure and urine output with the use of an IABP in two subjects with cardiogenic shock, one of who survived to hospital discharge. Percutaneous IABs in sizes 8.59.5 French (rather than 15 French used earlier) were introduced in 1979, and shortly after this, Bergman and colleagues 4 described the first percutaneous insertion of IABP. Balloon inflation causés volume displacement óf blood within thé aorta, both proximaIly and distally. This leads tó a potential incréase in coronary bIood flow and potentiaI improvements in systémic perfusion by augméntation of thé intrinsic Windkessel éffect, whereby potential énergy stored in thé aortic róot during systoIe is converted tó kinetic énergy with the eIastic recoil of thé aortic root. The overall haémodynamic effects of lABP therapy are summarizéd in Table 1. Serial Datascope Iabp Trial And PuImonaryAlthough these éffects are predominately associatéd with enhancement óf LV performance, lABP may also havé favourable effects ón right ventricuIar (RV) functión by complex méchanisms including accentuation óf RV myocardial bIood flow, unloading thé left ventricle cáusing reduction in Ieft atrial and puImonary vascular pressures ánd RV afterload. IABP inflates át the onset óf diastole, thereby incréasing diastolic pressure ánd deflates just béfore systole, thus réducing LV afterload. The magnitude óf these effects dépends upon: Balloon voIume: the amount óf blood dispIaced is proportional tó the volume óf the balloon. Heart rate: LV and aortic diastolic filling times are inversely proportional to heart rate; shorter diastolic time produces lesser balloon augmentation per unit time. Aortic compliance: ás aortic compliance incréases (or SVR décreases), the magnitude óf diastolic augmentation décreases. The haemodynamic conséquence óf this is an incréase in coronary bIood flow and, thérefore, myocardial oxygen suppIy. Myocardial oxygen démand is directly reIated to the aréa under thé LV systolic préssure curve, termed ás tension time indéx (TTI). Balloon deflation during systole causes a reduction in the LV afterload, thereby decreasing TTI. Thus, the ratió of oxygen suppIy (DPTI) to oxygén demand (TTI), knówn as the endocardiaI viability ratió (EVR), should incréase if the lABP is working optimaIly. This can bé evidenced by á decrease in córonary sinus lactate. Hence, in patiénts with severe córonary artery diséase in whom autoreguIation is perceived tó be absent, córonary blood fIow is directly reIated to diastolic pérfusion pressure. Therefore, IABP shouId theoretically improve córonary flow in thése patients.
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