Biomedical subjects

M Pine

Publications and source records attributed to M Pine.

26 records · Page 2Linked to original sources

PubMed1978

Mechanical circulatory support in postoperative cardiogenic shock.

A 38-year-old white woman had cardiogenic shock after elective mitral valve replacement and was unresponsive to pressor drugs and intra-aortic balloon counterpulsation. A left ventricular assist device (left ventricle to ascending aorta) was implanted 16 hours after the initial operation and provided circulatory support for 8 days. Improvement in the patient's own cardiac performance was documented, and there were no complications attributable to the assist device. However, intercurrent medical problems resulted in clinical deterioration on the fifth day after operation, and the patient died 8 days after operation. The findings in this patient suggest a potential role for this left ventricular assist device in future cases of acute, intractable, but potentially reversible myocardial failure.

Acute Kidney Injury↗

PubMed1976

The use of drug concentration measurements in studies of the therapeutic response to propranolol.

The dose of propranolol which produces the optimal therapeutic effect in patients with angina pectoris has been found to vary widely among patients. Because the plasma concentration of propranolol also differs markedly due to interpatient variability in absorption it seemed possible that this might be the reason for the wide range of effective doses in angina and that plasma propranolol might provide a useful guide to therapeutic response. To examine this possibility we selected ten patients with coronary artery disease complicated by angina and studied them at varying propranolol doses to a maximum of 320 mg/day. Exercise capacity was tested on a treadmill and plasma propranolol concentration was measured by gas liquid chromatography. In seven normal subjects beta-blockade was quantified precisely as inhibition of exercise tachycardia and was related to plasma propranolol levels at various doses. Maximal beta-blockade occurred at 100 ng/ml of plasma propranolol, but the dose response curve of blockade was relatively flat and the ED50 of plasma propranolol was 8+/-1 ng/ml. In the patients maximal therapeutic benefit from propranolol occurred at 30+/-7 ng/ml and at a dose of 144 mg/day. This resulted in an increase in exercise capacity from an estimated 12-7+/-0-8 ml/kg/min of oxygen consumption during control to 17-2+/-1-1 ml/kg/min on the drug. Thus, there was a wide variation of both dose and concentration among these patients at the maximum therapeutic response. However, when plasma propranolol was related to pharmacologic activity, the maximum therapeutic response was observed between 64 and 98% of total blockade. These studies indicated the extent of beta-blockade necessary to produce an effective therapeutic response in angina, but demonstrate that plasma drug levels provide no practical guide to therapy in patients with angina pectoris. A further study was conducted measuring plasma propranolol in twenty hypertensive patients to investigate the fall in blood pressure in relations to the change in plasma renin activity and the inhibition of cardiac adrenergic receptors. The inhibition of plasma renin closely resemble the response seen in heart rate inhibition in that the maximum response is seen at 100 ng/ml and the ED50 was 11 ng/ml. In contrast propranolol is shown only to begin to have a significant effect on blood pressure at a plasma level of 30 ng/ml and the effect becomes progressively greater as the plasma level increases. This suggests that the hypotensive effect of propranolol may be dissociated from the beta-blocking effects of cardiac and renin releasing receptors.

Angina Pectoris↗

PubMed1976

Homograft and prosthetic aortic valve replacement: a comparative study.

Homograft aortic valve replacement was done in 103 patients and prosthetic aortic valve replacement in 106 between January 1962 and December 1973. Patients who received homograft and prosthetic valves were compared with respect to age, sex, preoperative functional impairment, infection, dyspnea, angina, hemodynamics, chest X-ray, electrocardiogram, associated operations, early and late mortality, and valve failure. Combined total mortality was 28% (12% operative, 8% first postoperative year, 8% late). Ten percent of valve required replacement. One year after operation, 70% of survivors were asymptomatic, 27% were improved, and 3% were unchanged or between homograft and prosthetic valve replacement. Valve-related failure and infections were more common after homograft aortic valve replacement. Emboli, hemorrhage, and hemolysis were commoner after prosthetic valve replacement. Fungal infections occurred in five homograft patients but in no patient with a prosthetic aortic valve. Severe properative symptoms or recent endocarditis was associated with greater mortality and valve failure in both the homograft and the prosthetic series. Increased mortality and failure was also seen in patients with either preoperative aortic regurgitation with high left ventricular end-diastolic pressure and low cardiac index, or aortic stenosis with cardiomegaly or roentgenographic evidence of congestive heart failure. Therefore, in two series of patients at equal risk, mortality and valve failure were similar for homograft and prosthetic aortic valve replacement.

Adolescent↗

PubMed1975

Correlation of plasma propranolol concentration with therapeutic response in patients with angina pectoris.

The therapeutic response to propranolol was evaluated in patients with documented coronary artery disease at doses varying from 40 to 320 mg/day. Therapeutic response was quantified by evaluating exercise performance on a treadmill and then related to plasma propranolol concentration. Plasma propranolol was defined in terms of beta-adrenergic blockade by comparison with dose (concentration) response curves in normal subjects. Individual therapeutic benefit occurred at doses which averaged 144 +/- 21 mg/day and at concentrations which averaged 30 +/- 7 ng/ml. There was a wide variation between both dose and concentration among the patients at maximum therapeutic response, but when the plasma propranolol was related to pharmacologic activity, the maximum therapeutic response was observed between 64 to 98% of total blockade. Despite the increased exercise performance in these patients, the double product of heart rate and systolic blood pressure was always less, suggesting either an alteration of the relation between myocardial oxygen consumption and the double product during propranolol or a reduction on oxygen delivery to the myocardium as the result of beta-adrenergic blockade of the coronary vasculature.

Administration, Oral↗

PubMedDate not supplied

Severity-of-illness systems. An overview for medical directors--Part two.

In Part One of this article in the March-April 1990 issue of Physician Executive, the authors explored severity-of-illness systems that relied on administrative data for their formulation. In the second part of the article, the authors deal with systems that use clinical and/or physiologic data as their basis.

Clinical Medicine↗

PubMedDate not supplied

Severity-of-illness systems. An overview for medical directors--Part one.

To a baseball fan, the weight of a player's bat is not very important, and the grace with which it is swung has only slightly more appeal. Both these factors matter far less than how often and with what results the bat meets the ball. Similarly, in today's competitive health care environment, the medical director has to focus on results. Not only external demands from constituencies such as insurers, payers, consumers, and regulators, but also internal pressures for sound management decisions require accurate information about the outcomes of care. In this two-part article, the authors examine the contributions that severity-of-illness systems can make to outcomes monitoring.

Centers for Medicare and Medicaid Services, U.S.↗

PubMedDate not supplied

Combining information about process and outcomes to improve clinical care.

For some managers, clinical quality improvement begins and ends with measuring the clinical outcomes of care. For others, analyzing and altering processes of care are the central focus. To remove quality improvement from the realm of guesswork, these approaches must be intertwined. In health care, this linkage has appeared elusive. Now, using decision theory, there is a way.

Decision Making, Organizational↗

PubMedDate not supplied

Meet the mandate to measure clinical quality.

The mandate for health care organizations to be accountable for quality, as well as price, is now unavoidable. The Joint Commission's ORYX project is requiring every hospital to measure clinical outcomes of a majority of its patients within the next three years. This mandate can be met best with systems of clinical outcomes measurement that provide valid, reliable risk adjustment; yield meaningful information about many different diseases and procedures; and measure more than mortality or cost--all using primarily billing data. New outcomes measurement tools with all of these capabilities are available and have already enabled quality improvement in dozens of hospitals across the U.S.

Accreditation↗