Pulmonary artery catheterization

The indications for pulmonary artery catheterization are controversial. Because there is a lack of a well-defined outcome of data associated with this procedure, its use is presently best reserved for complicated cases of shock not responding to conventional fluid and medication therapies. Complications related to catheter insertion, maintenance, and removal include damage to vessels and organs during insertion, arrhythmias, infections, and thromboembolic damage. 

Pulmonary artery catheterization, introduced in 1970, is a routinely performed bedside procedure in many ICUs. With this... 

However, variable relationships between DO2 and V02 have been observed when VO2 was measnred independently by indirect calorimetry. A linear relationship between DO2 and VO2 therefore may be the result of mathematical coupling or flow-dependent V02. Currently available data do not support the concept that patient outcome or survival may be altered by treatment measures directed toward achieving supranormal DO2 and V02 values. In fact, a recent consensus conference concluded that although pulmonary artery catheterization is useful to guide therapy, routinely increasing cardiac index to... 

Bernard GR, Sopko G, Cerra R et al. Pulmonary artery catheterization and clinical outcomes National Heart, Ltmg, and Blood Institute and Food and Drug Administration Workshop Report. Consensus Statement. JAMA 2000 283 2568-2572. 

Practice guidelines for pulmonary artery catheterization An updated report by the American Society of Anesthesiologists Task Force on Pulmonary Artery Catheterization. Anesthesiology 2003 99 988— 1014. 

Part of the concern regarding pulmonary artery catheterization relates to interpretation of its results by inexperienced practitioners. Smdies in both Europe and the United States found that one of two physicians incorrectly interpreted a tracing from a pulmonary artery catheter. This could explain some of the results of smdies finding no benefits to pulmonary artery catheterization or, in some cases, worse outcomes in the pulmonary artery catheterization group by actions taken as a result of inaccurate measurements or misinterpretation of information obtained from the monitoring process. 

Morris D, Mulvihill D, Lew WY. Risk of developing complete heart block during bedside pulmonary artery catheterization in patients with left bundle-branch block. Arch Intern Med 1987 147 2005-2010. 

Sprung CL, Elser B, Schein RM, et al. Risk of right-bundle branch block and complete heart block during pulmonary artery catheterization. Crit Care Med 1989 17 1-3. 

The nonapeptide, bradykinin, has been reported to induce pulmonary vasodilatation in the foetal lamb. It was suggested that bradykinin might be responsible for the reactive hyperemia which ensues after ischemia in unventilated foetal lungs. The vasoactive polypeptide, substance P, reduced the pulmonary arterial pressure of anesthetized dogs, as measured by pulmonary artery catheterization S. The effect was transient in nature and thought to be the result of direct action on the pulmonary vasculature. 

The cardiac catheterization procednre reqnires vascnlar access, nsually obtained percutaneonsly at brachial or femoral arteries or veins. Left-sided catheterization provides access to the aorta, left ventricle, and left atrinm. Right-sided catheterization enables the right side of the heart, coronary sinus, pulmonary arteries, and pulmonary wedge position to be reached. Left-sided catheterization is used for coronary angiography and ventriculography, whereas rightsided catheterization is nsed for determination of cardiac performance parameters. 

For the growing number of patients with combined pulmonary hypertension and abnormal left ventricular hemodynamics, a careful hemodynamic study can help to delineate the subtleties of both diseases and response to therapies. Exercise catheterization is recommended in those patients with normal hemodynamics at rest, but with a pretest likelihood of PAH and/or other data suggesting exercise-induced symptoms, for instance, exercise echo or cardiopulmonary stress test. Unfortunately, to date there is no consensus as to the best exercise protocols for an appropriate hemodynamic assessment. Among those used include upright bicycle with neck pulmonary arterial (PA) lines at 75% predicted maximum exercise, supine bicycle, supine arm exercise, and supine volume loading. In all cases, it is essential to carefully measure PCWP, cardiac outputs, and PA pressures at consistent parts of the respiratory cycle, and not merely PA pressures. 

We challenged 12 patients with congenital heart disease and pulmonary hypertension preoperatively in the cardiac catheterization laboratory and nine postoperative patients (after cardiopulmonary bypass) with a 2-min infusion of 10 M acetylcholine into the pulmonary artery. The nine postoperative patients received a 15-min trial of inhaled nitric oxide following the infusion of acetylcholine. The results are shown in Figs. 4 and 5. The decrease in pulmonary artery pressure and resistance in the preoperative patients in response to acetylcholine was markedly attenuated postoperatively. The percentage reductions in pulmonary artery pressure preoperatively were 27% 4% and 9% 2% P < 0.003) postoperatively. Similarly, pulmonary vascular resistance decreased by 46% 5% compared to 11% 4% P < 0.002). However, the response to inhaled nitric oxide in the postoperative patients was marked vasodilation contrasted with the blunted effect of acetylcholine. Mean pulmonary artery pressure (34.4 2.6 versus... 

We investigated 11 patients (median age 13 years range, 0.7-27 years with pulmonary hypertension (mean pulmonary artery pressure, 71.6 8.4 mm Hg) who underwent cardiac catheterization as a prelude to transplantation of the heart, the lungs, or both. The patients were divided into two groups on the basis of left atrial pressure. Six patients had high mean left atrial pressures (27.0 4.2 mm Hg), elevated pulmonary ventricular resistance (mean, 14.9 3.8 U m ), and transpulmonary gradient (mean,... 

The most common lesion treated in the authors center is femoral artery thrombosis complicating catheterization, especially for balloon angioplasty of the aortic arch or aortic valve. These procedures require the insertion of a large balloon, which is currently mounted on large shafts. Initially a local low-dose approach from the opposite groin was preferred, but now systemic therapy is frequently used if there are no contraindications. Local low-dose thrombolysis is used for thrombosis of Blalock-Taussig shunts, dialysis fistula, pulmonary artery thrombosis, iliofemoral thrombophlebitis, aortic thrombosis in neonates, and brachial artery occlusion after supracondylar fracture. 

The literature includes eight case reports of pulmonary hypertension in AL amyloidosis attributed to pulmonary vascular amyloid deposition (Table 2). Autopsies confirmed pulmonary artery amyloid deposits in four out of four cases. The prevalence of restrictive cardiomyopathy and diastolic dysfunction in AL patients predisposes them to secondary forms of pulmonary vascular disease. Direct measurements of pulmonary artery pressures (PAP) were obtained in five cases (3 pulmonary arteriograms, 2 right heart catheterizations) however, only two reports include direct measures of left atrial filling pressures. Echocardio-graphic estimates of elevated right ventricular systolic pressures and normal diastolic function were reported in all cases. 

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