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S Zarich

Publications and source records attributed to S Zarich.

16 recordsLinked to original sources
PubMed2001

Impact of troponin T determinations on hospital resource utilization and costs in the evaluation of patients with suspected myocardial ischemia.

The evaluation and triage of patients with suspected myocardial ischemia in the emergency department remains challenging and costly. Previous studies of cardiac troponins have focused predominantly on patients with chest pain and have not randomized patients to different diagnostic strategies. Eight hundred fifty-six patients with suspected myocardial ischemia were prospectively randomized to receive a standard evaluation, including serial electrocardiographic and creatine phosphokinase-MB determinations (controls) or a standard evaluation with the addition of serial troponin T determinations (troponin group). The primary end points were length of stay and hospital charges. Significant reductions in length of hospital stay were seen in troponin T patients both with (3.6 vs 4.7 days; p = 0.01) and without (1.2 vs 1.6 days; p = 0.03) acute coronary syndromes compared with controls. Total hospital charges were reduced in a similar fashion in troponin patients with and without acute coronary syndromes ($15,004 vs $19,202; p = 0.01, and $4,487 vs $6,187; p = 0.17, respectively) compared with controls. Troponin patients without acute coronary syndromes had fewer hospital admissions (25% vs 31%; p = 0.04), whereas troponin patients with acute coronary syndromes had shorter telemetry and coronary care unit lengths of stay (3.5 vs 4.5 days; p = 0.03) compared with controls. Thus, utilization of troponin T in a broad spectrum of emergency department patients with suspected myocardial ischemia improves hospital resource utilization and reduces costs.

Adult↗
PubMed2000

Failure of a brief educational program to improve interpretation of pulmonary artery occlusion pressure tracings.

OBJECTIVE: To determine whether a brief educational program can reduce variability of interpretation of pulmonary artery occlusion pressure (PAOP) tracings. DESIGN: Prospective, observational study. PARTICIPANTS: Twenty-three intensive care nurses and 18 physicians. INTERVENTIONS: Participants interpreted PAOP tracings before and 1 week after receiving a single, brief educational session and/or written materials ("in-service") designed to reduce interobserver variability of PAOP interpretation. Differences between two reference values before and after in-service (mean population and Chief of Critical Care's readings) were compared for both groups. RESULTS: There were no significant differences in the variabilities in PAOP interpretations before and after in-service in either group. CONCLUSIONS: We conclude that this specific educational program was ineffective in reducing variability of interpretation of PAOP tracings. These data suggest that more comprehensive educational tools and/or sustained programs may be required to improve performance of critical care personnel in PAOP interpretation.

Cardiology↗
PubMed1999

Detecting and differentiating white from red coronary thrombus by angiography in angina pectoris and in acute myocardial infarction.

To determine the ability to detect thrombus by angiography, angioscopy was performed before angiography in patients undergoing interventional procedures and the data collected in a blinded fashion. These data demonstrated that the sensitivity of angiography to detect white thrombus was 50% and the specificity was 95%, whereas the sensitivity and specificity to detect red thrombus was 100%, respectively; the positive and negative predictive value of detecting thrombus in general was 89% and 83%, respectively.

Aged↗
PubMed1999

The Goldman algorithm revisited: prospective evaluation of a computer-derived algorithm versus unaided physician judgment in suspected acute myocardial infarction.

BACKGROUND: It has been nearly a decade since Goldman's computer-driven algorithm to predict myocardial infarction was validated. Despite the potential to avoid admission of patients without acute myocardial infarction (AMI) to the coronary care unit (CCU), the routine use of computer-generated protocols has not been widely adopted. METHODS: Two hundred consecutive patients admitted to a university-affiliated community hospital with the suspected diagnosis of AMI as determined by physicians without the aid of the Goldman protocol underwent a blinded prospective evaluation to assess the performance of the Goldman algorithm in predicting the presence of AMI. Over the same time period, the Goldman algorithm was applied by retrospective chart review in 762 patients with non-AMI admitting diagnoses. Prospective history, physical examination, and electrocardiographic data were obtained within 24 hours of admission to the CCU by a physician blinded to each patient's clinical course. Retrospective chart reviews were conducted for 762 patients with chest pain given with non-AMI diagnoses. RESULTS: The diagnosis of AMI was confirmed in 68.5% (137/200) of patients with suspected AMI admitted to the CCU. In prospective parallel evaluations the Goldman algorithm predicted the presence of AMI in 167 (83.5%) of these 200 patients. All 137 confirmed patients with AMI were correctly identified by the Goldman algorithm. All major in-hospital complications occurred in the 137 patients who were diagnosed as having AMI. Of the 762 patients with chest pain with non-AMI diagnoses, only 27 (3.5%) sustained an AMI. The Goldman algorithm predicted the presence of AMI in 85% (23/27) of these patients. Adherence to the use of Goldman's algorithm in the triage of chest pain could have prevented 16.5% of CCU admissions for AMI. CONCLUSIONS: Routine adherence to the Goldman algorithm for the evaluation of patients with acute chest pain could have decreased the number of CCU admissions for suspected AMI by 16. 5%. Because major in-hospital complications occurred only in patients with AMI, this strategy would result in significant cost savings to our health care system without jeopardizing patient safety.

Algorithms↗
PubMed1999

Myocardial ischemia and weaning failure in patients with coronary artery disease: an update.

OBJECTIVE: To determine the frequency and effects of weaning-related myocardial ischemia on weaning outcomes in patients with coronary artery disease. DESIGN: Prospective cohort study. SETTING: Medical and cardiac intensive care units of a 300-bed teaching community hospital. MEASUREMENTS AND MAIN RESULTS: Three-lead ST segments, heart rate-systolic blood pressure products, and respiratory rate/tidal volume ratios were obtained for patients with coronary artery disease just before and during their initial trials of weaning from mechanical ventilation. ST segments were interpreted by a blinded cardiologist. Eighty-three patients with a mean age of 72.4 +/- 1.1 years (mean +/- SEM), a mean Acute Physiology and Chronic Health Evaluation II score of 16.4 +/- 0.8, and a mean duration of mechanical ventilation of 4.6 +/- 0.9 days were studied. Eight patients showed electrocardiographic evidence of ischemia during weaning, and seven of these patients failed to be liberated on their first day of weaning. The presence of ischemia significantly increased the risk of weaning failure (risk ratio, 2.1; 95% confidence interval, 1.4-3.1). The rate-pressure product for the group as a whole increased significantly during weaning, from 11.9 +/- 0.4 to 13.5 +/- 0.5 mm Hg x beats/min x 10(3) (p < .01). The increase in rate-pressure product tended to be greater in patients who became ischemic (12.8 +/- 0.9 to 17.3 +/- 2.0 mm Hg x beats/min x 10(3)) than in patients who were not ischemic during weaning (11.8 +/- 0.4 to 13.0 +/- 0.5 mm Hg x beats/min x 10(3); p = .05). The rate/volume ratio did not change significantly during weaning, but the rate/volume ratios after both 1 min (65.6 +/- 4.6 vs. 98.0 +/- 9.4 breaths/min/L; p < .05) and 30 mins (68.6 +/- 4.3 vs. 91.1 +/- 8.9 breaths/min/L; p < .05) of unassisted breathing were lower in successful than in unsuccessful patients. CONCLUSION: Electrocardiographic evidence of myocardial ischemia occurs frequently and is associated with significantly increased risk of first-day weaning failure in patients with coronary artery disease.

APACHE↗
PubMed1999

Analysis of observer variability in measurement of pulmonary artery occlusion pressures.

The goal of this study was to determine inter- and intraobserver variability in measurement of pulmonary artery occlusion pressure (Ppao), comparing values recorded by critical care nurses and those measured by physician specialists. Critical care nurses (CCNs) obtained contiguous pulmonary artery and occlusion pressure paper tracings, up to twice a day, between June 1997 and March 1998. All tracings were interpreted on two separate occasions, in blinded fashion, by our Chiefs of Critical Care (CCMD) and Cardiology (CARD). Their values of Ppao were compared with those that had been recorded by CCNs. One hundred and forty-seven measurements of Ppao were performed on 40 patients with a mean age of 62.5 +/- 2.2 yr and a mean APACHE II score of 21.5 +/- 0.8. Either or both physician readers found 34 tracings as not satisfactory for Ppao interpretation. Intraobserver agreement of Ppao measurements, determined by correlation coefficients, was 0.91 for the CCMD and 0. 87 for the CARD. Correlation coefficients for interobserver comparisons were 0.83 for CCMD-CARD, 0.66 for CARD-CCN, and 0.67 for CCMD-CCN. Clinically significant differences were observed between CCMD-CARD (range of differences, -11 to 12 mm Hg), CARD-CCN (-13 to 15 mm Hg), and CCMD- CCN (-11 to 15 mm Hg). When Ppao readings were categorized as low (< 5 mm Hg), normal (5-15 mm Hg), and high (> 15 mm Hg), kappa values were 0.57 for CARD-CCMD, 0.51 for CARD-CCN, and 0.41 for CCMD-CCN comparisons. Interobserver variability was not explained by positive pressure ventilation or by the presence of (> 4 mm Hg) ventricular waves. The absolute values of interobserver differences in tracings with respiratory phasic variations (RPV) >/= 8 mm Hg were significantly greater than for tracings with variations < 8 mm Hg (p < 0.05, except CCMD-CCN, p = 0.10). Intraobserver differences also tended to be higher for tracings with RPV >/= 8 mm Hg (p = 0.06 and 0.05). When selected tracings were presented to 23 CCNs and 18 physicians, variability of Ppao interpretation was twice as great for tracings with large RPVs as compared with those with minimal RPVs. These data suggest that observer variability of Ppao interpretation is of potential clinical importance and that the degree of variability is associated with the magnitude of respiratory phasic variation of intrathoracic pressures. Although this could represent a local aberration, this study highlights a factor (respiratory phasic variation of Ppao) responsible for significantly increased intra- and interobserver variabilities.

APACHE↗
PubMed1999

Myocardial infarction complicating gastrointestinal hemorrhage.

OBJECTIVE: To determine the frequency of and risk factors for myocardial infarction (MI) in patients admitted to an intensive-care unit (ICU) with gastrointestinal (GI) hemorrhage and to ascertain the effects on mortality and lengths of stay. MATERIAL AND METHODS: Demographic, laboratory, and outcome data were determined for all patients admitted to a medical ICU with GI hemorrhage between April 1996 and January 1997. Serial creatine kinase with isoenzyme levels and electrocardiograms were interpreted blindly by a senior cardiologist. RESULTS: For 83 consecutive admissions to the ICU because of GI hemorrhage, the patients' mean (+/- standard error) age was 65.0 +/- 1.7 years and APACHE II (acute physiology and chronic health evaluation) score was 15.7 +/- 0.8. In-hospital death occurred in 16 patients (19%). Patients who did not survive had a lower admission systolic blood pressure (99.2 +/- 4.5 versus 115.0 +/- 4.0 mm Hg; P = 0.01) than did those who survived. Eleven of 83 patients (13%) fulfilled both enzymatic and electrocardiographic criteria for MI. Ten patients (12%) had electrocardiographic evidence of myocardial ischemia but did not meet criteria for MI. Patients with MI were older (74.4 +/- 4.0 versus 61.7 +/- 2.0 years; P < 0.05), had a higher acuity of illness (APACHE II score, 21.6 +/- 3.0 versus 14.6 +/- 0.7; P < 0.05), and had more coronary risk factors (2.3 +/- 0.3 versus 1.4 +/- 0.1; P < 0.05) in comparison with those without MI or ischemia. Patients with MI also had longer ICU (8.6 +/- 2.4 versus 3.3 +/- 0.4 days; P < 0.05) and hospital (16.3 +/- 3.4 versus 9.1 +/- 0.8 days; P < 0.05) lengths of stay. Patients older than 65 years had a threefold increased risk (risk ratio, 4.0; 95% confidence interval, 0.9 to 17.4) and those with two or more risk factors for coronary artery disease had a ninefold increased risk of MI (risk ratio, 10.2; 95% confidence interval, 1.4 to 76.1) in comparison with those who were younger or who had fewer coronary risk factors, respectively. MI complicating GI hemorrhage did not significantly affect the risk of in-hospital mortality (risk ratio, 1.5; 95% confidence interval, 0.5 to 4.4). CONCLUSION: MI occurs frequently in patients with GI hemorrhage admitted to an ICU. Age more than 65 years and two or more risk factors for coronary artery disease identify patients who are at greatest risk for occurrence of MI, which is associated with longer ICU and hospital stays.

APACHE↗
PubMed1996

Angioscopic predictors of early adverse outcome after coronary angioplasty in patients with unstable angina and non-Q-wave myocardial infarction.

BACKGROUND: Clinical and angiographic criteria have a limited ability to predict adverse outcome in patients with unstable angina who are undergoing percutaneous transluminal coronary angioplasty (PTCA). We investigated whether the use of angioscopy can improve prediction of early adverse outcome after PTCA. METHODS AND RESULTS: Angioscopic characterization of the culprit lesion was performed before PTCA in 32 patients with unstable angina and 10 with non-Q-wave infarction. Seven patients (17%) had an adverse outcome (myocardial infarction, repeat PTCA, or need for coronary artery bypass graft surgery) within 24 hours after PTCA. Six of 18 patients with a yellow culprit lesion had an adverse outcome compared with 1 of 24 in whom the culprit lesion was white (P = .03). Six of 20 patients with plaque disruption suffered an adverse outcome compared with 1 of 22 with nondisrupted plaques (P = .04). Six of 17 patients with intraluminal thrombus had an adverse outcome, whereas only 1 of 25 patients without thrombus suffered an adverse outcome (P = .01). Yellow color, disruption, and thrombus at the culprit lesion site were associated with an eightfold increase in risk of adverse outcome after PTCA. The prediction of PTCA outcome based on characteristics of the plaque that were identifiable by angioscopy was superior to that estimated by the use of angiographic variables. CONCLUSIONS: In patients with unstable angina and non-Q-wave infarction, angioscopic features of disruption, yellow color, or thrombus at the culprit lesion site can identify patients at high risk of early adverse outcome after PTCA. Angioscopy was superior to angiography for prediction of PTCA outcome.

Adult↗
PubMed1994

Effect of autonomic nervous system dysfunction on the circadian pattern of myocardial ischemia in diabetes mellitus.

OBJECTIVES: The aim of this study was to determine the prevalence and characteristics of ambulatory myocardial ischemia in patients with diabetes mellitus and to delineate the relation between the presence and severity of autonomic nervous system dysfunction and the incidence and time of onset of myocardial ischemia. BACKGROUND: Conflicting data exist with regard to the circadian pattern of myocardial infarction and other cardiovascular events, such as ambulatory ischemia, in diabetes. METHODS: We performed ambulatory electrocardiographic monitoring in 60 patients with diabetes and coronary artery disease. Autonomic nervous system testing was performed in a subgroup of 25 patients with myocardial ischemia after discontinuation of all antianginal medications. RESULTS: Thirty-eight of 60 patients had evidence of ambulatory ischemia; 91% of all ischemic episodes were asymptomatic. The 25 patients with ambulatory ischemia who underwent autonomic nervous system testing had a peak incidence of ischemia between 6 AM and noon (46 of 133 ischemic episodes, p < 0.007), compared with the other three 6-h periods. Fifteen of the 25 patients had no or mild autonomic nervous system dysfunction and demonstrated a similar peak incidence of ischemia between 6 AM and noon (p = 0.0009). However, the 10 patients with moderate to severe autonomic nervous system dysfunction did not experience a morning peak of ischemia, and the number of ischemic episodes was distributed evenly throughout the day (p = 0.4). CONCLUSIONS: Silent ischemia is highly prevalent among patients with diabetes and coronary artery disease. Time of onset of ischemia in diabetic patients follows a circadian distribution, with a peak incidence in the morning hours. However, patients with significant autonomic nervous system dysfunction did not demonstrate such a peak, suggesting that alterations in sympathovagal balance may have an effect on the circadian pattern of cardiovascular events.

Aged↗
PubMed1993

Spontaneous calcific embolization to the supraclinoid internal carotid artery from a regurgitant bicuspid aortic valve.

Calcific brain embolization leading to stroke is rarely recognized. We report a case of spontaneous embolization to the right cerebral circulation from a severely regurgitant, calcified bicuspid valve. Bicuspid aortic valves constitute the most common congenital heart abnormality, and have a tendency to become stenosed, regurgitant, calcified, or infected. The presence of heavy calcification in a noninfected bicuspid valve may lead to dislodgement of calcific embolic material which is not necessarily heralded by acute valvular rupture. Accurate localization of the calcific embolus to the right supraclinoid internal carotid artery was provided by spiral CT imaging in this case.

Adult↗
PubMed1988

Patent ductus arteriosus in the elderly.

Patent ductus arteriosus presenting in an elderly patient is unusual. This report describes the oldest patient (72 years) to undergo successful surgical interruption of a patent ductus arteriosus with a unique clinical presentation of typical angina pectoris with normal coronary anatomy. A possible pathophysiologic mechanism for this previously unreported presenting symptom is proposed. The natural history of patent ductus arteriosus and the role of surgery in the elderly patient are discussed.

Aged↗
PubMed1985

Fractional excretion of sodium. Exceptions to its diagnostic value.

Determining the cause of acutely deteriorating renal function is a common problem in clinical nephrology. The fractional excretion of filtered sodium (FENa) has been demonstrated to be a reliably discriminating test between prerenal azotemia and acute tubular necrosis. However, with increasing clinical use of the FENa, numerous reports of low FENa (less than 1%) have appeared. The clinical settings of these reports include oliguric and nonoliguric acute tubular necrosis, urinary tract obstruction, acute glomerulonephritis, hepatorenal syndrome, renal allograft rejection, sepsis, and drug-related alterations in renal hemodynamics. One particular urinary index cannot be expected to reliably discriminate between prerenal azotemia and acute renal failure in all cases. The utility of the FENa test in the differential diagnosis of acute renal failure must be interpreted in conjunction with the patient's clinical course and the use of additional urinary and serum tests.

Acute Kidney Injury↗
PubMedDate not supplied

Outcomes research is the fifth discipline of the fifth generation of managed care: utility of a single troponin-T.

OBJECTIVE: The fifth generation of managed care is disease management. Diseases have measurable risk in providing laboratory and medical services. The link between managing services and managing risk can be aided by leveraging the laboratory. We wish to remodel laboratory services to fit the needs of the use, thereby using the laboratory for competitive advantage by redesigning a desired output using a formal structured process. Outcomes research is the systems framework for the remodeling process through the link of laboratory output to clinical and financial outcomes. A process redesign model connects the use of laboratory tests to improved medical services by leveraging resources to achieve measurable improvement over current results. This view of outcomes research seeks both competitive advantage and measurable improvements in quality. METHODOLOGY: This approach is illustrated by the patient presenting with chest pain (CP). A majority of the patients rule out for acute myocardial infarction (AMI), including patients with indigestion, shortness of breath, and other clinical findings. This is the basis for an emergency department (ED) CP observation unit to reduce coronary care unit admission rates. When the Goldman algorithm for discharging low-risk patients with CP from the ED using only clinical features and electrocardiographic findings proved difficult to implement, we turned to measuring the diagnostic efficiency of a new cardiac marker to replace the evolutionary changes in creatine kinase (CK) isoenzyme MB. The physicians making the decision were blinded to the results of the study. We fitted the expected characteristics of the test to the expected results for our program. The test was done on the presenting specimen of 293 evaluable patients with a median of 6.5 hours from the time of onset of CP to the time the specimen was drawn. The result was compared with the evolutionary pattern of CK-MB. RESULTS: The sensitivity of the test at presentation to the ED was 85% compared with < 50% for the presenting CK-MB, the false negative results taken earlier than 3 hours or 10 days after the onset of symptoms. Troponin-T effectively identifies non Q-wave AMI much earlier than the CK-MB. This study led to a prospective randomized clinical trial to demonstrate an improved medical and financial benefit from an early rule in or rule out of severe coronary artery ischemia. CONCLUSION: The study supports our hypothesis that the laboratory can systematically redesign its technology strategy and participate in the construction of a clinical pathway for the discharge from ED or admitting decisions with a test 98% sensitive for identifying patients with serious coronary ischemia by 3.5 hours after the onset of symptoms.

Biomarkers↗
PubMedDate not supplied

Diagnosis of myocardial infarction: integration of serum markers and clinical descriptors using information theory.

OBJECTIVE: We examine the use of information theory applied to a single cardiac troponin T (cTnT) (first generation monoclonal; Boehringer Mannheim Corp., Indianapolis, Indiana) used with the character of chest pain, electrocardiography (ECG) and serial ECG changes in the evaluation of acute myocardial infarction (AMI). We combined a single measure of cTnT (blinded to the investigators) with a creatine kinase MB isoenzyme (CK-MB) measurement to discover the best decision value for this test in a study of 293 consecutive patients presenting to the emergency department with symptoms warranting exclusion of AMI. METHODS: The decision value for determining whether cTnT is positive or negative was determined independently of the final diagnosis by examining the information in the cTnT and CKMB data. Using information theory, an autocorrelation matrix with a one-to-one pairing of the CKMB and troponin T was constructed. The effective information, also known as Kullback entropy, assigned the values for troponin T and for CKMB that have the lowest frequency of misclassification error. The Kullback entropy is determined by subtracting the data entropy from the maximum entropy of the data set in which the information has been destroyed. The assignment of the optimum decision values was made independently of the clinical diagnoses without the construction of a receiver-operator characteristic curve (ROC). The final diagnosis of AMI was independently determined by the clinicians and entered into the medical record. RESULTS: The decision value for cTnT was 0.1 ng/ml as determined by the the information in the data. The method was validated within the same study by mapping the results so obtained into the diagnoses obtained independently by the clinicians using all of the methods at their disposal. The cTnT was different in AMI (n = 60) compared with non-AMI patients (n = 233) (2.08 +/- 0.21 vs. 0.07 +/- 0.10; p < .0001). CONCLUSION: Information theory provides a strong framework and methodology for determining the decision value for cTnT which minimizes misclassification errors at 0.1 ng/ml. The result has a strong correlation with other features in detecting AMI in patients presenting with chest pain.

Creatine Kinase↗
PubMedDate not supplied

Evaluating a new graphical ordinal logit method (GOLDminer) in the diagnosis of myocardial infarction utilizing clinical features and laboratory data.

OBJECTIVE: We used a new graphical ordinal logit method (GOLDminer) to assess a single cardiac troponin T (cTnT) analysis at the time of admission (first generation monoclonal; Roche BMC Corp., Indianapolis, Indiana), the character of chest pain, and electrocardiographic (ECG)findings in predicting the likelihood of acute myocardial infarction (AMI) in patients presenting with suspected myocardial ischemia. The final diagnosis of AMI was based on serial ECG findings and evolution of CKMB isoenzyme levels in conjunction with clinical findings. SUBJECTS: The study population consisted of 293 consecutive patients who presented at a mean of six hours after onset of chest pain or associated symptoms warranting a "rule-out" for AMI assessment to a university-affiliated community hospital. RESULTS: The odds-ratio for an elevated cTnT (> 0. 1 ng/ml) in AMI was 22.2:1. There was an association between typical chest pain and cTnT (chi square = 78.23, p < .0001) and between abnormal ECG findings and cTnT (chi square = 108, p < .0001). The cTnT yielded diagnostic benefit in addition to chest pain characteristics and ECG findings in AMI. We present the odds-ratios for the combined features in GOLDminer plots. CONCLUSION: We demonstrate how the odds-ratios for AMI are obtained after scaling continuous to ordinal the values for a single cTnT determination alone and with other features in patients presenting with chest pain.

Creatine Kinase↗