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ABSTRACT: The pulmonary artery catheter (PAC) continues to be used for monitoring of hemodynamics in patients undergoing coronary artery bypass graft (CABG) surgery despite concerns raised in other settings regarding both effectiveness and safety. Given the relative paucity of data regarding its use in CABG patients, and given entrenched practice patterns, we assessed the impact of PAC use on fatal and nonfatal CABG outcomes as practiced at a diverse set of medical centers.
Using a formal prospective observational study design, 5065 CABG patients from 70 centers were enrolled between November 1996 and June 2000 using a systemic sampling protocol. Propensity score matched-pair analysis was used to adjust for differences in likelihood of PAC insertion. The predefined composite endpoint was the occurrence of any of the following: death (any cause), cardiac dysfunction (myocardial infarction or congestive heart failure), cerebral dysfunction (stroke or encephalopathy), renal dysfunction (dysfunction or failure), or pulmonary dysfunction (acute respiratory distress syndrome). Secondary variables included treatment indices (inotrope use, fluid administration), duration of postoperative intubation, and intensive care unit length of stay. After categorization based on PAC and transesophageal echocardiography use (both, neither, PAC only, transesophageal echocardiography only), we performed the primary analysis contrasting PAC only and neither (total, 3321 patients), from which propensity paring yielded 1273 matched pairs.
The primary endpoint occurred in 271 PAC patients versus 196 without PAC (21.3% vs.15.4%; adjusted odds ratio [AOR], 1.68; 95% confidence interval [CI], 1.24 to 2.26; P<0.001). The PAC group had an increased risk of all-cause mortality, 3.5% vs 1.7% (AOR, 2.08; 95% CI, 1.11 to 3.88; P=0.02) and an increased risk of cardiac (AOR, 1.58; 95% CI, 1.14 to 2.20; P=0.007), cerebral (AOR, 2.02; 95% CI, 1.08 to 3.77; P=0.03) and renal (AOR, 2.47; 95% CI, 1.68 to 3.62; P<0.001) morbid outcomes. PAC patients received inotropic drugs more frequently (57.8% vs 50.0%; P<0.001), had a larger positive IV fluid balance after surgery (3220 mL vs 3022 mL; P=0.003), and experienced longer time to tracheal extubation (15.40 hours [11.28/20.80] versus 13.18 hours [9.58/19.33], median plus Q1/Q3 interquartile range; P<0.0001). Use of PAC was also associated with prolonged intensive care unit stay (14.5% vs 10.1%; AOR, 1.55; 95% CI, 1.06 to 2.27; P=0.02).
Use of a PAC during CABG surgery was associated with increased mortality and a higher risk of severe end-organ complications in this propensity-matched observational study. A randomized controlled trial with defined hemodynamic goals would be ideal to either confirm or refute our findings.
Anesthesia and analgesia 09/2011; 113(5):994-1002. · 3.08 Impact Factor
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New England Journal of Medicine 04/2010; 362(16):e57. · 53.30 Impact Factor
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ABSTRACT: Direct thrombin inhibitors (DTIs) provide an alternative method of anticoagulation for patients with a history of heparin-induced thrombocytopenia (HIT) or HIT with thrombosis (HITT) undergoing cardiopulmonary bypass (CPB). In the following report, a 65-year-old critically ill patient with a suspected history of HITT was administered argatroban for anticoagulation on bypass during heart transplantation. The patient required massive transfusion support (55 units of red blood cells, 42 units of fresh-frozen plasma, 40 units of cryoprecipitate, 40 units of platelets, and three doses of recombinant Factor VIIa) for severe intraoperative and postoperative bleeding.
Plasma samples from before and after CPB were analyzed postoperatively for argatroban concentration using a modified ecarin clotting time (ECT) assay.
Unexpectedly high concentrations of argatroban were measured in these samples (range, 0-32 microg/mL), and a prolonged plasma argatroban half life (t(1/2)) of 514 minutes was observed (published elimination t(1/2) is 39-51 minutes [< or = 181 minutes with hepatic impairment]).
Correlation of plasma argatroban concentration versus the patient's coagulation variables and clinical course suggest that prolonged elevated levels of plasma argatroban may have contributed to the patient's extended coagulopathy. Because DTIs do not have reversal agents, surgical teams and transfusion services should remain aware of the possibility of massive transfusion events during anticoagulation with these agents. This is the first report to measure plasma argatroban concentration in the context of CPB and extended coagulopathy.
Transfusion 12/2009; 50(4):801-7. · 3.22 Impact Factor
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Paul Barash
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ABSTRACT: Central venous catheterization is a critical component of management for the critically ill patient in the operating room and intensive care unit. When using ultrasound techniques for central venous access, access is achieved with fewer attempts, a reduced incidence of carotid artery punctures or 'hits', an increased success rate, and a decreased duration of procedure compared to the traditional landmark approach.
F1000 Medicine Reports 01/2009; 1.
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Anesthesia and analgesia 08/2008; 107(2):362-4. · 3.08 Impact Factor
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Anesthesia and analgesia 04/2007; 104(3):507-8. · 3.08 Impact Factor
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ABSTRACT: Heparin-induced thrombocytopenia (HIT) is being recognized in an increasing number of patients referred for cardiac surgery, as a result of previous exposure to heparin. We present a case of a patient with HIT scheduled for aortic valve replacement and coronary bypass graft surgery, who was managed with the direct thrombin inhibitor, argatroban for anticoagulation during cardiopulmonary bypass (CPB). The patient sustained continued bleeding in excess of the acknowledged half-life of the drug and required a substantial number of blood products to restore coagulation following CPB. Pertinent reports using argatroban for cardiac surgery with CPB are reviewed in the context of the present case report. The pharmacologic basis, cost analysis and resource utilization of heparin substitutes are discussed for the patient with HIT requiring CPB.
Connecticut medicine 05/2006; 70(4):245-50.
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ABSTRACT: The human ascending aorta becomes markedly prone to rupture and dissection at a diameter of 6 cm. The mechanical substrate for this malignant behavior is unknown. This investigation applied engineering analysis to human ascending aortic aneurysms and compared their structural characteristics with those of normal aortas.
We measured the mechanical characteristics of the aorta by direct epiaortic echocardiography at the time of surgery in 33 patients with ascending aortic aneurysm undergoing aortic replacement and in 20 control patients with normal aortas undergoing coronary artery bypass grafting. Six parameters were measured in all patients: aortic diameter in systole and diastole, aortic wall thickness in systole and diastole, and blood pressure in systole and diastole. These were used to calculate mechanical characteristics of the aorta from standard equations. Aortic distensibility reflects the elastic qualities of the aorta. Aortic wall stress reflects the disrupting force experienced within the aortic wall. Incremental elastic modulus indicates loss of elasticity reserve.
Aortic distensibility falls to extremely low levels as aortic dimension rises toward 6 cm (3.02 mm Hg(-1) for small aortas versus 1.45 mm Hg(-1) for aortas larger than 5 cm, P < .05). Aortic wall stress rises to 157.8 kPa for the aneurysmal aorta, compared with 92.5 kPa for normal aortas. For 6-cm aortas at pressures of 200 mm Hg or more, wall stress rises to 857 kPa, nearly exceeding the known maximal tensile strength of human aneurysmal aortic wall. Incremental elastic modulus deteriorates (1.93 +/- 0.88 MPa vs 1.18 +/- 0.21 MPa, P < .05) in aneurysmal aortas relative to that in normal aortas.
The mechanical properties of the aneurysmal aorta deteriorate dramatically as the aorta enlarges, reaching critical levels associated with rupture by a diameter of 6 cm. This mechanical deterioration provides an explanation in engineering terms for the malignant clinical behavior (rupture and dissection) of the aorta at these dimensions. This work adds to our fundamental understanding of the biology of aortic aneurysms and promises to permit future application of engineering measurements to supplement aneurysm size in clinical decision making in aneurysmal disease.
Journal of Thoracic and Cardiovascular Surgery 10/2005; 130(3):677-83. · 3.41 Impact Factor
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JAMA The Journal of the American Medical Association 01/2004; 290(21):2803. · 30.03 Impact Factor
