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L K Brath

Publications and source records attributed to L K Brath.

4 recordsLinked to original sources
PubMed1996

Cardiac complications in noncardiac surgery: relative value of resting two-dimensional echocardiography and dipyridamole thallium imaging.

Although perfusion imaging studies are extensively used as a preoperative screening test for risk stratification of patients undergoing noncardiac surgery, no single cardiac noninvasive test has been shown to be ideal for risk stratification. We investigated the relative impact of transthoracic two-dimensional echocardiography (ECHO) compared with dipyridamole thallium scintigraphy (DT) in predicting major cardiac complications in patients undergoing non-cardiac surgery. Eighty-seven consecutive patients undergoing 96 procedures (56 vascular, 40 general) underwent preoperative evaluation first with DT and then with ECHO before surgery. Complications were prospectively defined as myocardial infarction (MI), cardiac death (of MI, heart failure, or arrhythmia), or need of revascularization before surgery. DT showed one or more reversible defects in 44 (51%) patients, whereas ECHO demonstrated a reduced left ventricular ejection fraction (LVEF) in 25 (29%) patients. Major postoperative cardiac complications occurred in 10 patients: 5 deaths (2 ventricular fibrillation, 3 fatal MIs) and 5 nonfatal MIs. Four additional patients required urgent revascularization (coronary bypass graft surgery in 3 and percutaneous transluminal coronary angioplasty in 1). Of the 20 patients with both abnormal DT and ECHO, 11 (55%) had major complications, compared with none of the 26 (0%; p < 0.01) with an abnormal DT but normal LVEF. The sensitivity of DT and ECHO were not significantly different (79% [95% Cl, 52% to 93%] vs 86% [60% to 96%], respectively), although the specificity of DT was lower (51% [40% to 62%] vs 81% [70% to 88%]; p < 0.05). The positive predictive value of DT was significantly improved from 22% (12% to 35%) to 52% (32% to 72%) when both DT and ECHO were abnormal. The results were not significantly different when the 4 patients who underwent revascularization were excluded. In conclusion, (1) in spite of similar sensitivity of ECHO and DT, ECHO appears to be relatively more specific in predicting major CC, and (2) when ECHO and DT are both abnormal, the risk of CC related to noncardiac surgery is significantly increased. Use of the combination of DT and ECHO before major noncardiac surgery can improve the identification of patients at risk for complications.

Aged↗
PubMed1996

Cardiac complications in noncardiac surgery: value of dobutamine stress echocardiography versus dipyridamole thallium imaging.

OBJECTIVES: The objective of this study was to determine the relative value of dobutamine stress echocardiography (DSE) and dipyridamole thallium imaging (DT) in the preoperative assessment of cardiovascular risk before noncardiac surgery. DESIGN: Prospectively DSE was performed in patients who had undergone DT as a part of their preoperative evaluation. SETTING: A large urban veterans' affairs medical center. PARTICIPANTS: Thirty-seven patients undergoing major noncardiac surgery were assessed for complications during a 1-month follow-up period. INTERVENTIONS: Both DSE and DT were performed before surgery. The medium interval between the two tests were 15.5 days. MEASUREMENTS: Left ventricular wall motion was assessed at baseline and peak dobutamine dose in a standard fashion. Wall motion was scored and indexed using a 16-segment model. A positive DSE was defined as failure of augmentation, new or worsening of baseline wall motion abnormalities in two or more contiguous segments. Myocardial perfusion studies after DT were performed according to conventional method. A positive DT was defined as a reversible perfusion defect, increased lung uptake, and/or transient left ventricular dilatation. Complications were defined as myocardial infarction or cardiac death occurring as a result of the operation, or need for revascularization before surgery. RESULTS: DSE was positive in 19 patients, whereas DT was positive in 25 patients. Fourteen patients had both an abnormal DSE and DT. Five patients had major postoperative cardiac complications: fetal myocardial infarction (1); fatal cardiac arrest (1); and severe coronary artery disease necessitating coronary artery bypass surgery (2) or percutaneous transluminal coronary angioplasty (1). DSE was positive in all 5 (100%), whereas DT was positive in 4 of 5 (80%) patients with complications. The sensitivity for each test was comparable: for DSE it was 100% (95% C.I. 56% to 100%) and for DT 80% (37% to 96%). Specificity for DSE (60%, 43%-74%) was somewhat higher than DT (38%, 24% to 54%), although this did not reach statistical significance (p = 0.06). CONCLUSIONS: The ability of DSE to predict major cardiac complications related to noncardiac surgery appears to be similar to DT and may be used as an alternative to DT imaging in the preoperative risk assessment of patients undergoing noncardiac surgery.

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PubMed1994

Do "screening" coagulation tests predict bleeding in patients undergoing fiberoptic bronchoscopy with biopsy?

OBJECTIVE: To determine if preprocedure coagulation testing predicts bleeding in patients undergoing flexible fiberoptic bronchoscopy (FOB) with biopsy. DESIGN: Retrospective chart review. SETTING: Southeastern, urban Veteran Affairs Medical Center. MEASUREMENTS AND MAIN RESULTS: Two hundred seventy-four patient charts representing 305 FOB with biopsy were reviewed for clinical predictors of bleeding, prebronchoscopy laboratory abnormalities, and incidence of bleeding complications. Thirty-five patients bled, and 3 had abnormal results of coagulation studies. Normal results of coagulation studies and no clinical risk factors were noted in 68 percent of patients who bled. CONCLUSION: Patients undergoing flexible FOB with biopsy do not benefit from preprocedure coagulation testing.

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