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Biomedical subjects

John Kellett

Publications and source records attributed to John Kellett.

13 recordsLinked to original sources
PubMed2005

Risk stratification of chest pain patients by point-of-care cardiac troponin T and myoglobin measured in the emergency department.

A prospective multicenter study including 1410 chest pain patients with suspected acute coronary syndromes was carried out to examine the predictive value of biological cardiac markers for adverse events measured by a point-of-care system. Admission cardiac troponin T (cTnT) and myoglobin were measured in parallel on a point-of-care system in the emergency department and -- together with CK-MB mass -- on lab analyzers. In a one-year follow-up, cardiac and non-cardiac death, acute myocardial infarction, unstable angina pectoris and need for revascularization were registered. Median time between onset of symptoms and admission was 285 min; 172 patients (12.2%) had no event during follow-up. If the cTnT, measured either by the point-of-care system or a conventional lab analyzer, was >0.05 microg/L, then the chance of a cardiac event during the follow-up period was doubled (18% vs. 9%). Serial cTnT measurement did not add any further value to the predictive power of the admission cTnT. Myoglobin and CK-MB mass identified increasing risk with increasing concentration quartiles; cardiac event rates were 2.8- to 4.4-fold higher between the quartiles with the lowest and those with the highest analyte concentration, respectively. There was no difference in non-cardiac death rates between any concentration quartiles. In conclusion, the prediction of clinical events by cardiac troponin T and myoglobin measured with a point-of-care analyzer in the emergency department was as good as that of the same cardiac markers and CK-MB mass measured on lab analyzers.

Aged↗
PubMed2005

The prediction of in-hospital mortality by amino terminal pro-brain natriuretic peptide (NT-proBNP) levels and other independent variables in acutely ill patients with suspected heart disease.

BACKGROUND: Amino terminal pro-brain natriuretic peptide (NT-proBNP) measurement can detect and assess heart failure. However, compared with traditional clinical parameters, its value in predicting the in-hospital mortality of patients with suspected heart disease has not been reported. METHODS: We examined the ability of 11 continuous and 21 categorical variables, including NT-proBNP levels measured at the time of admission, to predict in-hospital mortality. The setting was a small Irish rural hospital where 342 consecutive patients with suspected heart disease were admitted as acute medical emergencies. RESULTS: The 31 patients who died while in hospital had significantly higher NT-proBNP levels on admission than patients discharged alive (11,548+/-13,531 vs. 3805+/-6914 pg/mL, p<0.0001). Patients who died in-hospital were older, had significantly higher white cell counts, blood urea and modified early warning (MEW) scores, and lower temperatures, blood pressures and oxygen saturation. Four variables were found to be independent predictors of in-hospital mortality: a systolic blood pressure equal to or below 100 mm Hg, a urea level above 13 mmol/L, a white cell count greater than 13*10(9)/L and a NT-proBNP level greater than or equal to 11,500 pg/mL. The presence of three of these variables was associated with an in-hospital mortality rate of 54%. CONCLUSIONS: Four variables (i.e. hypotension, elevated urea, leukocytosis and elevated NT-proBNP levels) are comparable independent predictors of in-hospital mortality.

Journal Article↗
PubMed2005

How many patients in atrial fibrillation admitted to an acute medical unit will benefit from oral anticoagulation? Application of the results of the major randomized controlled trials to 141 consecutive, unselected, elderly patients using a decision support computer program.

BACKGROUND: Although several randomized, control trials (RTC) suggest that oral anticoagulation (OAC) benefits patients with atrial fibrillation (AF), this might not be true for hospitalized patients with co-morbid conditions. If the results of the RTCs are valid, then how many patients in AF admitted to an acute medical unit will benefit from OAC? METHODS: An RCT-based decision analysis model calculated the quality-adjusted life expectancy (QALE) gain from OAC for 141 unselected consecutive patients over 65 years of age with AF admitted to an acute medical unit. RESULTS: If treated with aspirin, all 141 patients were predicted to gain QALE compared with placebo. If the quality of life adjustment (QoLA) on OAC was the same as placebo, then 104 patients were predicted to benefit from OAC compared with aspirin, while 63 patients were predicted to benefit at a QoLA of 0.99 (overall benefit 0.13+/-0.15 QALYs, range 0.01-0.88 QALYs). These 63 patients were more likely to have had a stroke, diabetes, hypertension, heart failure or heart attack, and less likely to have impaired renal function than those predicted not to benefit. The 78 patients predicted not to benefit from OAC included 11 younger patients without heart failure, hypertension, diabetes or cerebrovascular disease; the remaining 67 patients, however, were older, more likely to have heart failure and/or renal impairment and were at high risk of both stroke and bleeding. CONCLUSION: An RCT-based decision analysis model suggests that more than half the patients in AF admitted to a small rural hospital with acute medical conditions are unlikely to benefit from OAC, while all will benefit from aspirin.

Journal Article↗
PubMed2004

Prediction of in-hospital mortality by brain natriuretic peptide levels and other independent variables in acutely ill patients with suspected heart disease.

BACKGROUND: Brain natriuretic peptide (BNP) measurement can detect and assess heart failure. However, compared with traditional clinical parameters, its value for predicting the in-hospital mortality of patients with suspected heart disease has not been reported. STUDY DESIGN: Examination of the ability of 11 continuous and 22 categorical variables, including BNP levels measured at the time of admission, was conducted to predict in-hospital mortality. SETTING: A small, rural Irish hospital. SUBJECTS: Six hundred forty-two consecutive patients with suspected heart disease admitted as acute medical emergencies. RESULTS: Thirty-eight (5.9%) patients died while in hospital. They had significantly higher BNP levels on admission than did patients subsequently discharged alive (763+/-473 pg/mL versus 368+/-412 pg/mL, P<0.0001). Patients who died in hospital were older; had significantly higher white blood cell counts, blood urea, respiratory rates and modified early warning scores; and had significantly lower blood pressure and hemoglobin levels. Five variables were found to be independent predictors of mortality: a systolic blood pressure of 90 mmHg or less; a hemoglobin level of 100 g/L or less; a white blood cell count greater than 13.0 x 10(9)/L being unwell before the current illness; and a BNP level of 700 pg/mL or greater. The presence of three or more of these variables was associated with an in-hospital mortality rate of 39%. CONCLUSIONS: Five independent variables (hypotension, anemia, leukocytosis, prior illness and elevated BNP levels) are comparable predictors of in-hospital mortality in patients with suspected heart disease.

Adolescent↗
PubMed2004

Determining the need for coronary revascularization by an exercise test assessment computer program (ETAP).

The rate at which coronary artery revascularization procedures are performed remains inconsistent, and their risks may be greater and long-term benefits less than imagined by the general public and open to considerable inter-individual variation. However, these risks and benefits can be explicitly estimated for an individual patient from a brief medical history and the results of a standard exercise test by a computer program that uses conventional medical decision making techniques. The program first estimates the prior and post-exercise test probability of coronary artery disease and then employs a decision analysis model to define the risks and benefits associated with different treatment options. These results are provided in a printed report that can become part of the clinical record to be reviewed with the patient. In contrast with traditional clinical intuition, the program consistently and explicitly defines the risks and benefits of coronary artery disease treatments. The program forces physicians and their patients to appraise critically the information and beliefs upon which they base their clinical decisions.

Journal Article↗