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T A Manolio

Publications and source records attributed to T A Manolio.

103 records · Page 6Linked to original sources

Regional versus general anesthesia in high-risk surgical patients: the need for a clinical trial.

Regional anesthesia is often preferred over general anesthesia for patients with cardiovascular disease because of presumed decreased risk of perioperative myocardial ischemia. However, few studies have addressed this issue directly. To determine whether the type of anesthesia is independently associated with myocardial ischemia, records of 134 patients undergoing peripheral vascular grafting under general or regional anesthesia were examined. There were no significant differences preoperatively between groups in ASA class, age, sex, or prevalence of angina, diabetes, or hypertension. Twelve patients developed myocardial ischemia or infarction within 7 days of operation; 11 of these 12 patients had received regional anesthesia (p less than 0.015). The association between anesthetic approach and perioperative myocardial ischemia or infarction remained after adjustment for preoperative factors associated with ischemia or with type of anesthesia. General anesthesia does not appear to be associated with increased risk of myocardial ischemia, and stringent recommendations to avoid it in this population may be unfounded. A clinical trial is needed to define more clearly the risks and benefits of different types of anesthesia in high-risk patients.

Anesthesia, Conduction↗

Handgrip strength after the Blalock-Taussig shunt: 14 to 34 year follow-up.

To determine the long-term functional impact of the Blalock-Taussig (BT) shunt, we studied handgrip strength in 56 patients (10-28 years) following total repair of tetralogy of Fallot. Of the 56, 16 (29%) had a previous right BT shunt, 5 of 56 (9%) had a previous left BT shunt, and the remaining 35 patients either had a Potts shunt or primary total repair. The mean age at the time of right BT was 2.8 +/- 1.6 (SD) years, left BT 1.7 +/- 1.2 years, and total repair for all patients was 7.1 +/- 2.2 years. Mean age at the time of study was 26 +/- 9 years. Right-and left-handgrip strength were measured with a Jamar dynamometer, averaging the results of grip position 2, 3, and 4 to accommodate variation in hand size. Since absolute values of hand strength were strongly associated with sex (p = 0.006) and body surface area (p = 0.016), we calculated the ratio of right-hand to left-handgrip strength (RL ratio). The RL ratios were: 0.98 +/- 0.13 (right BT), 1.21 +/- 0.11 (left BT), and 1.13 +/- 0.16 (no BT): (p = 0.004 right BT vs. no BT, p = 0.07 left BT vs. no BT, Wilcoxon rank sum test). Thus, although frequently clinically inapparent, handgrip strength tested many years post-BT shunt is reduced on the side of the shunt.

Adult↗

Evaluation of the Dinamap continuous blood pressure monitor.

The validity of the Dinamap automated oscillometric blood pressure monitor, an instrument frequently used for continuous monitoring in intensive care settings, was evaluated in comparison to two standard methods of blood pressure measurement. Oscillometric monitoring was compared to random-zero sphygmomanometry in 28 ambulatory subjects, using the instruments in a random order. The oscillometric monitor overestimated random-zero systolic pressure (mean difference = 5.7 mm Hg; P less than 0.001), but did not differ in diastolic pressure (difference = 1.3 mm Hg, P greater than 0.3). Correlation (r) between methods was 0.94 for systolic pressure and 0.83 for diastolic pressure. Repeatability of sequential measures did not differ between methods. To evaluate the oscillometric monitor in the intraoperative setting, it was used simultaneously with a radial artery catheter to measure blood pressure in 14 patients undergoing peripheral vascular or other major surgery. The oscillometric monitor underestimated intra-arterial systolic pressure (mean difference = -9.4 mm Hg; P less than 0.002), but overestimated intraarterial diastolic pressure (difference = 5.7 mm Hg; P less than 0.005). There was no difference in mean arterial pressure (P greater than 0.1). Correlation between methods was 0.88 for systolic, 0.71 for diastolic, and 0.79 for mean arterial pressure. The oscillometric instrument had a sensitivity of 63% and specificity of 97% in detecting intraarterial systolic pressures of 160 mm Hg or greater, and a sensitivity of 89% and specificity of 89% in detecting intraarterial systolic pressures of 100 mm Hg or less. These findings demonstrate differences between the oscillometric monitor and other standard methods of blood pressure measurement.(ABSTRACT TRUNCATED AT 250 WORDS)

Arteries↗

Hemodynamic effects of primary closure of omphalocele/gastroschisis in human newborns.

To determine whether they could establish reliable, objective criteria that would predict safe, primary closure of abdominal wall defects (omphalocele/gastroschisis) in newborn infants, the authors measured intraoperative changes in intra-gastric pressure (IGP), central venous pressure (CVP), cardiac index (CI), systolic arterial blood pressure (BP), and heart rate (HR). Eleven neonates, who averaged 2.7 kg (range 1.5-4.1 kg) and 36 weeks gestation (range 30-41 weeks) were anesthetized with fentanyl (7.5-12.5 micrograms/kg), metocurine (0.3 mg/kg), and oxygen. Three infants had defects that were too large to close primarily. Of the eight infants who underwent primary closure, four required re-operation within 24 h because of oliguria or poor peripheral perfusion. Infants who required re-operation had intra-gastric pressures of 20 mmHg or more, a decrease in CI of 0.78 1.min.m2 or more, and an increase in CVP of 4 mmHg or more. Heart rate, BP, and systemic vascular resistance did not differ in infants requiring and not requiring re-operation. The authors conclude that intraoperative measurement of changes in IGP, CVP, and/or CI can reliably predict success or failure of primary operative repair of abdominal wall defects in human neonates.

Abdominal Muscles↗

Long-term valvular function after total repair of tetralogy of Fallot. Relation to ventricular arrhythmias.

Patients with total repair of tetralogy of Fallot may have residual valvular dysfunction, the long-term effect of which is poorly defined. We prospectively studied 59 patients for 18 +/- 5 (mean +/- SD) years postoperatively by Doppler echocardiography and by 24-hour electrocardiographic monitoring. Right ventricular outflow gradients were estimated from the peak continuous-wave Doppler pulmonary artery velocity. The severity of valvular regurgitation was determined by mapping the proximal chamber by pulsed Doppler methods. Right ventricular diastolic cavity area was measured by planimetry of the apical image. The right ventricular outflow tract gradient had a mean value of 9.4 +/- 9.0 mm Hg (range, 0-58 mm Hg; median, 6.6 mm Hg). Pulmonary regurgitation was present in 78% of patients, with 59% of patients graded as mild and 19% as moderate. Tricuspid regurgitation was found in 65% of patients, with 56% of patients graded as mild, 7% as moderate, and 2% as severe. The severity of pulmonary regurgitation correlated with right ventricular cavity area (p less than 0.05). The severity of tricuspid regurgitation was not related to pulmonary stenosis or to the severity of pulmonary regurgitation. Aortic regurgitation is unusual (n = 11) and correlates with aortic root size. The frequency and type of ventricular arrhythmia were not related to the severity of pulmonary stenosis; however, ventricular bigeminy and couplets were related to the severity of pulmonary regurgitation (p less than 0.025). The majority of patients with total repair of tetralogy of Fallot have remarkably good long-term valvular function. For the minority with moderate or severe valvular dysfunction, pulmonary regurgitation is the best marker for ventricular arrhythmias.

Adult↗

Multivariate analysis of factors associated with unplanned admission in 'outpatient' ophthalmic surgery.

We performed a case-control study of patients undergoing planned "outpatient" ophthalmic surgery in order to identify risk factors associated with the need for unplanned admission to the hospital. factors associated with admission included time of completion of surgery, duration of operation, fentanyl dose, use of enflurane, and leukocytosis. A multiple logistic regression model found each of these variables except duration of operation to to be independently associated with unplanned admission with admission included age, present or past medical conditions, use of medications, blood pressure, hematocrit, serum sodium or potassium, and ASA Class. Identification and modification of these factors may help anticipate and/or reduced the incidence of unplanned admission to the hospital in patients undergoing planned outpatient surgery.

Ambulatory Care↗

The effects of age on outcome after coronary bypass surgery.

To study the effects of increasing age on outcome after coronary artery bypass grafting (CABG), 684 patients who underwent CABG from 1980 to 1985 were entered into a noncurrent prospective study. Patients were matched by date of operation and placed into three groups according to age: (1) 70 and older, (2) 55 to 69, or (3) less than 55. In addition to intraoperative and postoperative data collected on all patients, follow-up was obtained on 97% of the patients at a mean of 30 +/- 16 months. Older patients were more often female (p less than .002), and white (p less than .001) and had more preexisting cerebrovascular disease (p less than .0001), peripheral vascular disease (p less than .001), unstable angina (p less than .0001), and longer mean bypass pump times (p less than .001). Older patients had a higher hospital mortality (9.3% vs 2.2%), suffered more complications, including stroke, wound infection, reoperation for bleeding, need for intropic drug support, and prolonged ventilation, and had longer mean postoperative hospital stays (14 vs 9 days, p less than .0001). After discharge, mortality rates were similar in all groups, as was recurrence of symptoms and degree of rehabilitation. While patient age at operation significantly influenced hospital mortality and morbidity, this appeared to be a consequence of the greater frequency of risk factors in patients over 70 years of age. In addition, late follow-up failed to demonstrate any significant differences based on age alone in survival or functional status among patients undergoing CABG.

Activities of Daily Living↗

Major stroke after coronary artery bypass surgery: changing magnitude of the problem.

Between January 1974 and December 1984, 3816 patients underwent isolated CABG at this hospital. During this 11-year interval, the number of patients having operation annually as well as the mean age at operation of the patients have increased significantly. The increase in the mean age from 51.9 years in 1974 to 59.4 years in 1984 occurred while the operative mortality rate fell significantly from 3.9% in 1974 to 2.0% in 1984. Although the overall incidence of major stroke was 1.8%, the stroke rate increased during this interval to 2.4% from 1982 to 1984. This higher stroke rate correlates significantly with the increasing age of the CABG patients, with the stroke risk five times greater for patients in their 70s compared with patients between 51 and 60 years old. Specific risk factors for the development of stroke during CABG in addition to age were examined and discussed.

Aged↗

Stroke following coronary artery bypass grafting: a ten-year study.

To identify possible risk factors for the occurrence of stroke during coronary artery bypass grafting (CABG), the cases of 3,279 consecutive patients having isolated CABG from 1974 to 1983 were reviewed. During this period, the risk of death fell from 3.9% to 2.6%. The stroke rate, however, fell initially but then rose from 0.57% in 1979 to 2.4% in 1983. Adjustment of these data for age clearly demonstrated that the risk of stroke has increased largely because of an increase in the mean age of patients undergoing CABG procedures. A case-control study involving all 56 stroke victims and 112 control patients was used to identify those risk factors significantly associated with the development of stroke in univariate analysis: increased age (63 versus 57 years in stroke patients and controls, respectively; p less than 0.0001); preexisting cerebrovascular disease (20% versus 8%; p less than 0.03); severe atherosclerosis of the ascending aorta (14% versus 3%; p less than 0.005); protracted cardiopulmonary bypass time (122 minutes versus 105 minutes; p less than 0.005); and severe perioperative hypotension (23% versus 4%; p less than 0.0001). Other variables not found to correlate with postoperative stroke included previous myocardial infarction, hypertension, diabetes mellitus, lower extremity vascular disease, preoperative left ventricular function, and intraoperative perfusion techniques. Elderly patients who have preexisting cerebrovascular disease or severe atherosclerosis of the ascending aorta or who require extensive revascularization procedures have a significantly increased risk of postoperative stroke.

Age Factors↗

Cholesterol and heart disease in older persons and women. Review of an NHLBI workshop.

The value of serum total cholesterol measurement in predicting coronary heart disease (CHD) is well established in middle-aged men, but has been questioned in middle-aged women and older people of both sexes. To address this, the most recent follow-up data from 25 populations in 22 US and international cohort studies were presented and analyzed at a recent National Heart, Lung, and Blood Institute (NHLBI) workshop. Crude relative and absolute excess risks of fatal CHD were determined for individual studies and pooled across studies to determine pooled risk estimates. Serum total cholesterol and low-density-lipoprotein (LDL) cholesterol levels predicted fatal CHD in middle-aged (< 65 years) and older (> or = 65 years) men and women, though the strength and consistency of these relationships in older women were diminished. High-density-lipoprotein (HDL) cholesterol levels inversely predicted CHD in middle-aged men and women and in older women, but not in older men. Data for minority groups and for overseas populations were similar to those for white people in the United States. Relative risk estimates were generally lower for older than for middle-aged subjects, but absolute excess risk was greater. Older people and middle-aged women with elevated cholesterol levels are clearly at increased risk of coronary disease; whether this risk can be modified by dietary or drug therapy, and at what level intervention is appropriate, must not be determined.

Age Factors↗

Echocardiographic design of a multicenter investigation of free-living elderly subjects: the Cardiovascular Health Study.

The Framingham study has shown by M-mode echocardiography that left ventricular hypertrophy is a powerful, independent predictor for the development of coronary heart disease and that increased left atrial dimension has been associated with an increased risk of stroke. No previous population-based study has evaluated the risk factor correlates and predictive value for coronary heart disease and stroke of two-dimensional and Doppler, as well as M-mode, echocardiography. The Cardiovascular Health Study is a multi-year prospective epidemiologic study of 5201 men and women older than 65 recruited from four geographic sites in the United States. The main objectives of incorporating echocardiography were to determine whether echocardiographic indices, or changes in these indices, are (1) correlated with traditional risk factors for coronary heart disease and stroke; and (2) independent predictors of morbidity and mortality for coronary heart disease and stroke. Echocardiographic measurements of interest include those related to global and segmental left ventricular systolic and diastolic structure and function and left atrial size. For each subject, a baseline echocardiogram was recorded in super-VHS tape using a standard protocol and equipment. All studies were sent to a reading center where images were digitized and measurements were made using customized computer algorithms. Calculated data and images were stored on optical disks to facilitate retrieval and future comparisons in longitudinal studies. A second echocardiogram is scheduled in year 7, with a goal of determining whether changes in cardiac anatomy or function over a 5-year period are important predictors of morbidity or mortality from coronary heart disease and stroke. Quality control measures included standardized training of echocardiography technicians and readers, technician observation by a trained echocardiographer, periodic blind duplicate readings with reader review sessions, phantom studies, and quality control adults.

Allied Health Personnel↗

Clinical correlates of ventricular and sulcal size on cranial magnetic resonance imaging of 3,301 elderly people. The Cardiovascular Health Study. Collaborative Research Group.

To identify potential risk factors for and clinical manifestations of ventricular and sulcal enlargement on cranial magnetic resonance imaging (MRI), 3,301 community-dwelling people 65 years or older without a history of stroke or transient ischemic attack underwent extensive standardized evaluations and MRI. In the multivariate model, increased age and white matter grade on MRI were the dominant risk factors for ventricular and sulcal grade. For ventricular grade, other than race, for which non-Blacks had higher grades, models for men and women shared no other factors. For sulcal grades, models for men and women shared variables reflecting cigarette smoking and diabetes. Clinical features were correlated more strongly with ventricular than sulcal grade and more strongly for women than men. Significant age-adjusted correlations between ventricular grade and the Digit-Symbol Substitution Test were found for men and women. Prospective studies will be needed to extend findings of this cross-sectional analysis.

Age Distribution↗

Association of fasting insulin with blood pressure and lipids in young adults. The CARDIA study.

The association of insulin with cardiovascular disease (CVD) may be mediated in part by the associations of insulin with CVD risk factors, particularly blood pressure and serum lipids. These associations were examined in 4576 black and white young adults in the CARDIA Study. Fasting insulin level was correlated in univariate analysis with systolic blood pressure (r = 0.16), diastolic blood pressure (r = 0.13), triglycerides (r = 0.27), total cholesterol (r = 0.10), high density lipoprotein (HDL) cholesterol (r = -0.25), and low density lipoprotein (LDL) cholesterol (r = 0.14), and with age, sex, race, glucose, body mass index, alcohol intake, cigarette use, physical activity, and treadmill duration (all p less than 0.0001). After adjustment for these covariates, insulin remained positively associated with blood pressure, triglycerides, total and LDL cholesterol, and apolipoprotein B and was negatively associated with HDL, HDL2 and HDL3 cholesterol, and apolipoprotein A-I in all four race-sex groups. Higher levels of fasting insulin are associated with unfavorable levels of CVD risk factors in young adults; these associations, though relatively small, can be expected to increase the risk of atherosclerosis. Demonstration of these relationships in a large, racially diverse, healthy population suggests that insulin may be an important intermediate risk factor for CVD in a broad segment of the U.S. population.

Adolescent↗