PubMed Health⌕ Search

Biomedical subjects

L K Smith

Publications and source records attributed to L K Smith.

At least 19 recordsLinked to original sources
PubMed1992

Medical treatment after myocardial infarction. Results of studies using various methods.

Patients who have had myocardial infarction and are at risk for continued problems may benefit from several treatment methods (table 1). Beta-adrenergic blockers reduce subsequent cardiovascular morbidity and mortality through their effect on the myocardial supply-demand balance. Administration of angiotensin-converting enzyme inhibitors reduces morbidity and mortality rates in myocardial infarction survivors who have diminished left ventricular ejection fraction. Aspirin and other anticoagulants are beneficial through their antiplatelet effects. Cardiac rehabilitation methods and aggressive management of lipids levels are also useful.

Adrenergic beta-Antagonists↗
PubMed1992

Comparison of three progressive exercise protocols in peripheral vascular occlusive disease.

Although claudication pain and hemodynamic responses to exercise are usually clinically assessed via graded treadmill walking, measuring these responses to other commonly performed tasks may yield a more nearly complete evaluation of peripheral vascular occlusive disease. Thus, the purpose of this study was twofold: (1) to determine the reliability of claudication and hemodynamic responses to level walking and stairclimbing and (2) to compare these responses with those obtained with graded walking at similar oxygen consumption. Ten patients with stable claudication symptoms performed graded walking, level walking, and stairclimbing progressive protocols with respective increases in grade, walking speed, and stepping rate on a modified stairclimbing device every two minutes. Similar peak oxygen consumption (13.60 to 14.18 mL/kg/min) was attained with the three protocols (P = NS). Reliability coefficients for the times to onset and to maximal claudication pain during level walking (R = 0.95 and 0.95, respectively) and during stairclimbing (R = 0.92 and 0.82, respectively) were similar to those previously obtained during graded walking. Reliability coefficients for foot transcutaneous oxygen tension during and following level walking (R = 0.78 to 0.96) and stairclimbing (R = 0.65 to 0.98) and for ankle systolic blood pressure following level walking (R = 0.95 to 0.97) and stairclimbing (R = 0.90 to 0.98) were also similar to those previously found with graded walking. Additionally, claudication and hemodynamic measurements were similar among the three exercise protocols. Thus, because graded walking, level walking, and stairclimbing progressive exercise protocols yield reliable and similar information about the hemodynamic severity of peripheral vascular occlusive disease, only one is needed for evaluation.

Aged↗
PubMed1992

The impact of a family-centered case management approach.

Two urban programs of family-centered case management services were established for families of children with both a developmental disability and a chronic health condition. These are children who present significant caregiving demands due to the long-term and severe nature of their disabilities. Thirty-two mothers were interviewed within the family's first month in the project and reinterviewed approximately one year later. The results indicate that more families received respite care, nursing services, training in the care of the child, educational services and transportation to school at follow-up than had been receiving those services at baseline. However, families still indicated high service needs for recreational activities, life planning, regular day care, legal services, and speech therapy at follow-up. Mothers indicated that program services were helpful in obtaining services, financing, information, support, and advocacy. Although maternal life satisfaction improved with program participation, non-handicapped siblings continued to have difficulties coping. The model employed is described and the practice and policy implications of the findings discussed.

Adolescent↗
PubMed1992

Prediction of claudication pain from clinical measurements obtained at rest.

The ability to predict claudication pain during single-stage (S) and progressive (P) treadmill protocols from clinical measurements obtained at rest was examined. Peripheral hemodynamic measurements from the more severely diseased lower limb and medical history data were obtained from 56 claudicant patients during supine rest immediately preceding S (1.5 mph and 7.5% grade) and P (2 mph, 0% grade with 2% increase every 2 min) treadmill protocols. Distance walked to onset of claudication pain (CPD) and to maximal pain (MPD) during both protocols were recorded. The claudication distances during the S protocol were not correlated with either the peripheral hemodynamic or medical history variables. In contrast, CPD and MPD during the P protocol were predicted (P less than 0.05) by ankle/brachial systolic blood pressure index (ABI) (quadratic relationship), laterality of claudication pain (1 = unilateral, 2 = bilateral), and gender (1 = female, 2 = male) from the following regression equations: CDP (m) = 159.9 - (321.8 x ABI) + (445.6 x ABI2) - (93.5 x laterality) + (99.0 x gender), R = 0.74, R2 = 0.55, adjusted R2 = 0.53, SEE = 110.5, P less than 0.0001; and MPD (m) = 83.1 + (195.0 x ABI) + (174.0 x ABI2) - (76.4 x laterality) + (114.2 x gender), R = 0.76, R2 = 0.58, adjusted R2 = 0.55, SEE = 138.3, P less than 0.0001. It is concluded that the regression equations for the prediction of CPD and MPD may be used to quickly estimate the functional severity of peripheral vascular occlusive disease in clinical settings where treadmill testing is not feasible or is impractical.

Aged↗
PubMed1991

Effects of handrail support on claudication and hemodynamic responses to single-stage and progressive treadmill protocols in peripheral vascular occlusive disease.

Because handrail support reduces the energy cost of treadmill walking, claudication and hemodynamic responses of patients with peripheral vascular occlusive disease should also be affected. Furthermore, the reliability of the test results may be reduced unless the same pressure is applied to the handrails over repeated tests. The effect of handrail support on claudication and hemodynamic responses, and on their reliability, were examined during single-stage (2 mph, 12% grade) and progressive (2 mph, 0% grade with 2% increase every 2 minutes) treadmill protocols. Ten patients with stable disease performed both protocols 3 times, separated by 1 week, with and without handrail support. Claudication pain distance and maximal walking distance were greater (p less than 0.05) when handrail support was permitted, and they increased (p less than 0.05) over repeated tests of each protocol. No increase was noted over the tests without support. The responses and reliability of foot transcutaneous oxygen tension, ankle systolic pressure and ankle/brachial systolic pressure index after exercise to maximal tolerable pain were not affected by handrail support. Because claudication distances were altered, it is concluded that handrail support should not be allowed when assessing claudicants, unless balance cannot otherwise be maintained.

Aged↗
PubMed1991

Relationship between foot transcutaneous oxygen tension and ankle systolic blood pressure at rest and following exercise.

To determine whether foot transcutaneous oxygen tension (TcPO2) and ankle systolic blood pressure (SBP) measure similar aspects of peripheral vascular occlusive disease (PVOD), the authors examined their relationship at rest and following treadmill exercise. Thirty-seven PVOD patients (mean age 69.2 +/- 0.8 years) rested supine for twenty minutes, followed by a progressive treadmill walking test at a constant speed of 2 mph. The initial grade was 0%; this increased 2% every two minutes until maximal claudication pain (n = 19) or until the occurrence of such limiting symptoms as volitional fatigue (n = 6), ST segment depression (n = 4), dyspnea (n = 3), multiple premature ventricular contractions (n = 2), and angina (n = 2). Patients then rested supine for fifteen minutes. Foot TcPO2 was recorded before, during, and after exercise, whereas ankle SBP was measured before and after exercise. At rest, a curvilinear relationship was found between foot TcPO2 and ankle SBP (foot TcPO2 = 41.89 + 0.22(ankle SBP) + 0.0005 (ankle SBP2); SEE = 9.2, R = 0.64, R2 = 0.41, p less than 0.001). In contrast, the relationship was stronger and more linear during recovery, particularly at the sixth minute (foot TcPO2) = 8.33 + 0.35 (ankle SBP); SEE = 13.6, R = 0.86, R2 = 0.73, p less than 0.001). At rest, foot TcPO2 and ankle SBP characterized different aspects of PVOD because they shared only 41% common variance. During recovery, they provided similar information because up to 73% of the variance was shared. It is concluded that foot TcPO2 should also be used to assess PVOD patients because unique information is obtained at rest and values can be recorded during exercise.

Aged↗
PubMed1991

Exercise training in patients with impaired left ventricular function.

Advances in the understanding of the pathophysiology of congestive heart failure have guided efforts in formulating effective treatment strategies. The epidemiology, etiology, and medical management of congestive failure are reviewed. The changing approaches to exercise and exercise training in patients with heart failure are discussed. Recent studies of the impact of exercise training in this important patient group are presented.

Adaptation, Physiological↗
PubMed1991

Progressive vs single-stage treadmill tests for evaluation of claudication.

The reliability of claudication pain and the metabolic and hemodynamic measurements of the lower limbs of patients with stable peripheral vascular occlusive disease (PVOD) were compared during and following single-stage (S) and progressive (P) treadmill tests. Ten patients (69.8 +/- 1.8 yr; X +/- SE) walked to maximal claudication pain twice a month for 4 months. Patients walked at 1.5 mph up a 7.5% grade (S test) and at 2 mph on a 0% grade, increasing by 2% every 2 min (P test). Distance walked to the onset of claudication pain (CPD) and maximal walking distance (MWD) were recorded. Foot transcutaneous oxygen tension (TcPO2) was measured before, during, and after exercise, while ankle systolic blood pressure (SBP) and the ankle-to-brachial SBP index (ABI) were measured before and after exercise. Intraclass correlation coefficients (R) of CPD and MWD during S tests were R = 0.53 and R = 0.55, respectively. In contrast, the respective R values during P tests were R = 0.89 and R = 0.93. Higher R values of foot TcPO2 were also obtained during and following P tests, while ankle SBP and ABI were highly reliable following both tests. It is concluded that the severity of PVOD is better assessed by P treadmill tests because clinical measurements are more reliable during exercise and recovery.

Aged↗
PubMed1990

Effect of phospholipase C from Bacillus cereus on the release of membrane-bound choline-O-acetyltransferase from rat hippocampal tissue.

Some of the enzyme choline-O-acetyltransferase (ChAT) associated with central cholinergic nerve terminals appears to be non-ionically associated with membranes. In the present study, we tested the possibility that some membrane-bound ChAT might be anchored to membranes by a phosphatidylinositol linkage by incubating rat hippocampal tissue with phospholipase C (PLC) from Bacillus cereus. The PLC selectively augmented the release of ChAT; also, the glycosylphosphatidylinositol-PLC inhibitor, zinc, blocked this increase in release. When control and PLC-treated hippocampal tissues were subjected to Triton X-114 phase separation, a procedure that separates amphiphilic from hydrophilic proteins, the detergent-soluble, membrane-bound fraction of tissue ChAT appeared to be the source of the ChAT released by PLC into the incubation medium. Zinc also blocked the temperature-dependent release of ChAT, but not lactic dehydrogenase, from hippocampal tissue. Extracellular membrane-bound ChAT appeared to be the source of the ChAT released by a low exogenous concentration of PLC, as well as that released by a temperature-dependent process during tissue incubation. Phosphatidylinositol-specific PLC from Bacillus thuringiensis released ChAT, but not lactic dehydrogenase, from a crude synaptosomal fraction prepared from rat hippocampal tissue. These results suggest that some of the membrane-bound ChAT in rat hippocampal tissue may be extracellular and anchored to the membrane by phosphatidylinositol, and also that an endogenous factor in hippocampal tissue may function to remove this extracellular ChAT from the membrane.

Animals↗
PubMed1988

Medical clearance for vigorous exercise. Clinical evaluation and exercise testing.

The practitioner plays an important role in providing guidance for exercise. Physical activity is one component of a life-style aimed at enhancing the health of the individual. When entered into with appropriate understanding and with reasonable expectations and goals, exercise can also be a major source of enjoyment. The role of the practitioner is to guide the patient to an appropriate level and intensity of exercise carried out in a suitable setting. In identifying the health habits and risk factors of the patient seeking clearance for an exercise program, physicians can do more than simply address the exercise issue. They can seize the opportunity to take a broader look at the patient's entire cardiovascular status and guide the patient into a generally beneficial program of health enhancement.

Coronary Disease↗
PubMed1988

Cardiac disorders: a guide to assessing risk in the elderly.

Coronary artery disease can have various clinical manifestations, from the presence of "silent" ischemia to the occurrence of an acute myocardial infarction and congestive myopathy. At each point in the clinical manifestation of coronary artery disease, the practitioner has an evolving number of techniques available to guide decisions regarding prognosis and therapy. Guidelines exist for defining which patients with "silent" ischemia need further evaluation. The clinically manifested occurrence of angina pectoris is commonly encountered in the elderly. Prognostic stratification can occur using both invasive and non-invasive techniques. Even patients with unstable angina have different outcomes depending upon clinical presentation and therapeutic management. Finally, a large pool of patients who survive an acute myocardial infarction have a varied prognosis depending upon certain risk markers as documented with widely available non-invasive testing. This article summarizes the evaluations and decisions the physician can make regarding patients who present with the various manifestations of coronary artery disease and provides a summary of recent data supporting decisions regarding prognosis and therapy.

Aged↗
PubMed1987

Comparison of hydrochlorothiazide and sustained-release diltiazem for mild-to-moderate systemic hypertension.

The safety and efficacy of sustained-release diltiazem, 120 to 180 mg twice daily, was compared with those of hydrochlorothiazide, 25 to 50 mg twice daily, in 207 patients with mild-to-moderate hypertension (supine diastolic blood pressure [BP] 95 to 114 mm Hg) using a baseline, placebo, parallel-design study protocol. All patients received placebo for 2 to 4 weeks, followed by either study drug during the double-blind phase, titrated over 8 weeks to achieve a goal of supine diastolic BP reduction of at least 10 mm Hg and/or a diastolic BP of less than 90 mm Hg. Patients not achieving the treatment goal with either drug alone received the other drug in combination. Both drugs produced significant decreases in supine and upright BP throughout the 26-week study. The magnitude of decrease in mean supine diastolic BP was similar for both drugs as monotherapy at week 14 (-11.4 and -12.1 mm Hg, respectively). Hydrochlorothiazide produced significantly greater reductions at week 14 in mean supine systolic BP than sustained-release diltiazem (-19.5 and -12.7 mm Hg, respectively). The difference in mean supine diastolic BP reduction with the 2 drugs diminished when hydrochlorothiazide (50 mg/day) was compared with sustained-release diltiazem. The BP effects were sustained for 6 months with both drugs. The 2 drugs appeared to lower BP more in patients older than 60 years and more in black than in white patients. The combination of the 2 drugs decreased supine diastolic BP to goal levels in about 56% of the patients not achieving goal with either drug alone. Adverse effects were minimal with either drug alone and in combination, except for hypokalemia, which increased with thiazide alone and in combination.

Adult↗
PubMed1985

Diuretics versus calcium-channel blockers in systemic hypertension: a preliminary multicenter experience with hydrochlorothiazide and sustained-release diltiazem.

The safety and efficacy of sustained-release diltiazem 120 to 180 mg, 2 times a day, were compared with hydrochlorothiazide 25 to 50 mg, 2 times a day, and the combination of diltiazem and hydrochlorothiazide in 56 patients with mild to moderate hypertension (supine diastolic blood pressure between 95 and 114 mm Hg) using a placebo-controlled, parallel-design protocol. Data from an additional 21 patients were evaluated for safety only. The data reported herein represent the preliminary experience from a larger 200-patient multicenter study. All patients received placebo for 4 weeks, followed by either hydrochlorothiazide or diltiazem titrated to achieve a diastolic blood pressure reduction of greater than or equal to 10 mm Hg to reach a goal supine diastolic blood pressure of less than 90 mm Hg. Patients not achieving the treatment goal received hydrochlorothiazide plus diltiazem. At week 14, on maintenance monotherapy, diltiazem and hydrochlorothiazide produced comparable reductions in blood pressure from placebo baseline (160.3 +/- 24.3/101.7 +/- 5.5 to 145.2 +/- 24.1/89.8 +/- 7.4 mm Hg with diltiazem, 156.0 +/- 15.6/103.7 +/- 4.7 to 134.1 +/- 12.5/89.2 +/- 9.5 mm Hg with hydrochlorothiazide, p less than 0.001 for both). Diltiazem and hydrochlorothiazide achieved goal blood pressure in 42% and 45% of patients, respectively. The effects in responders were sustained for 6 months. In patients who did not achieve the treatment goal, 63% responded to diltiazem plus hydrochlorothiazide.No clinically significant postural hypotension was observed on any regimen. Heart rate was slightly lower with diltiazem than with hydrochlorothiazide. Adverse effects were minimal with diltiazem, hydrochlorothiazide and diltiazem plus hydrochlorothiazide but more hypokalemia occurred with hydrochlorothiazide.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1979

Mexican-American views of Anglo medical and dietetic practices.

Institutions involved in health care delivery and foodservice to a population with large ethnic communities might increase their effectiveness if they knew the possible influences of the folklore or local customs of these groups on the attitudes of their patients. The observations and survey of Spanish-speaking patients by the Department of Food Services at the University of Arizona Health Science Center should be a stimulus for further study of ethnic groups by health professionals.

Arizona↗
PubMed1978

Management of hypercholesterolemia: evaluation of practical clinical approaches in healthy young adults.

A work site-located clinic screened 6,000 employees (91 percent participation) and identified 146 hypercholesterolemic subjects (100 percent initial participation, 12 percent subsequent dropout rate). The subjects, aged 20 to 50 years, were randomly classified into four groups: Group A, treatment in a lipid intervention clinic with diet for 6 weeks, then diet plus clofibrate for the subsequent 18 weeks; Group B, diet treatment from a clinic nutritionist with the cooperation of the subject's private physician; Group C, referral for treatment by a private physician; and Group D, no intervention. Initial mean cholesterol was 294 mg/100 ml. At 24 weeks, all intervention groups had decreases in serum cholesterol (Group A, 12 percent; Group B, 15 percent; Group C, 17 percent; P less than 0.001). The control group (D) had a small decrease in cholesterol (4 percent). Decreases in cholesterol were correlated with weight loss and decrease in fasting serum triglycerides but not with the use of clofibrate. Serum cholesterol can be reduced in healthy young adults by several practical methods.

Adult↗