PubMed Health⌕ Search

Biomedical subjects

Lawrence H Muhlbaier

Publications and source records attributed to Lawrence H Muhlbaier.

16 recordsLinked to original sources
PubMed2007

Is early too early? Effect of shorter stays after bypass surgery.

BACKGROUND: Postoperative stays after coronary artery bypass graft surgery (CABG) decreased substantially in the 1990s. Although shorter stays offer clinical benefits, premature discharge could increase adverse events and offset initial savings. This study examined the effect of early discharge after CABG on readmission/death and cost within 60 days of discharge home. Variability in hospitals' tendencies for early discharge and adverse outcomes was also explored. METHODS: Analyses were based on clinical and claims data for 55,889 New York CABG patients discharged home 1995 to 1998. Early discharge was defined as a postoperative stay below the 15th percentile for patients with similar risk. The likelihood of early discharge and its effect on readmission/death were examined using hierarchical logistic regression, accounting for patient risk and within-hospital correlation. The correlation between early discharge and adverse outcomes at the hospital level was assessed. The effect of early discharge on subsequent inpatient, outpatient, skilled nursing, and home health costs was examined in the Medicare subset. RESULTS: Overall, 17% of patients were discharged early, with increasing prevalence over time. The tendency to discharge early varied widely among hospitals (2% to 42% of patients). We found no association between hospitals' tendencies for early discharge and adverse outcomes. Lower postdischarge costs among patients discharged early (mean = 3,491 dollars versus 5,246 dollars for typical stays) resulted in average cumulative savings of 6,309 dollars. CONCLUSIONS: Patients selected for earlier discharge after CABG did not have increased adverse event rates or higher costs. Variation among hospitals in early discharge suggests that more efficient patient management could be achieved at some hospitals.

Aged↗
PubMed2006

Long-term adherence to evidence-based secondary prevention therapies in coronary artery disease.

BACKGROUND: Studies have examined the use of evidence-based therapies for coronary artery disease (CAD) in the short term and at hospital discharge, but few have evaluated long-term use. METHODS AND RESULTS: Using the Duke Databank for Cardiovascular Disease for the years 1995 to 2002, we determined the annual prevalence and consistency of self-reported use of aspirin, beta-blockers, lipid-lowering agents, and their combinations in all CAD patients and of angiotensin-converting enzyme inhibitors (ACEIs) in those with and without heart failure. Logistic-regression models identified characteristics associated with consistent use (reported on > or =2 consecutive follow-up surveys and then through death, withdrawal, or study end), and Cox proportional-hazards models explored the association of consistent use with mortality. Use of all agents and combinations thereof increased yearly. In 2002, 83% reported aspirin use; 61%, beta-blocker use; 63%, lipid-lowering therapy use; 54%, aspirin and beta-blocker use; and 39%, use of all 3. Consistent use was as follows: For aspirin, 71%; beta-blockers, 46%; lipid-lowering therapy, 44%; aspirin and beta-blockers, 36%; and all 3, 21%. Among patients without heart failure, 39% reported ACEI use in 2002; consistent use was 20%. Among heart failure patients, ACEI use was 51% in 2002 and consistent use, 39%. Except for ACEIs among patients without heart failure, consistent use was associated with lower adjusted mortality: Aspirin hazard ratio (HR), 0.58 and 95% confidence interval (CI), 0.54 to 0.62; beta-blockers, HR, 0.63 and 95% CI, 0.59 to 0.67; lipid-lowering therapy, HR, 0.52 and 95% CI, 0.42 to 0.65; all 3, HR, 0.67 and 95% CI, 0.59 to 0.77; aspirin and beta-blockers, HR, 0.61 and 95% CI, 0.57 to 0.65; and ACEIs among heart failure patients, HR, 0.75 and 95% CI, 0.67 to 0.84. CONCLUSIONS: Use of evidence-based therapies for CAD has improved but remains suboptimal. Although improved discharge prescription of these agents is needed, considerable attention must also be focused on understanding and improving long-term adherence.

Aged↗
PubMed2006

Effects of decreased preoperative endotoxin core antibody levels on long-term mortality after coronary artery bypass graft surgery.

HYPOTHESIS: Decreased preoperative levels of antiendotoxin core antibody (EndoCAb) in patients undergoing cardiac surgery with cardiopulmonary bypass are associated with increased long-term mortality. DESIGN: Observational study. SETTING: Academic medical center. PATIENTS: A total of 474 patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass. INTERVENTIONS: Preoperative serum IgM EndoCAb levels were determined, and established preoperative risk factors were assessed. Patients were assigned a risk score using a validated method. MAIN OUTCOME MEASURES: The primary end point was mortality. Statistical analysis used the Cox proportional hazards regression model with log EndoCAb as the predictor of interest and Parsonnet additive risk score as a covariate. Kaplan-Meier survival curves were generated to visually compare groups with high vs low EndoCAb levels. RESULTS: Forty-six deaths occurred in 5 years. Annual follow-up rates during the 5 years were 100%, 94%, 93%, 98%, and 98% for the 1-, 2-, 3-, 4-, and 5-year periods, respectively. Parsonnet additive risk score (hazard ratio, 1.07; 95% confidence interval [CI], 1.04-1.11; P < .001) and log EndoCAb (hazard ratio, 0.73; 95% CI, 0.53-0.99; P = .04) were independent predictors of long-term mortality in the final model. Kaplan-Meier analysis revealed that the preoperative EndoCAb level was significantly associated with mortality up to 5 years (P = .01 by log-rank test). CONCLUSION: Lower preoperative serum EndoCAb level is a significant predictor of long-term mortality independent of other known risk factors.

Biomarkers↗
PubMed2006

Multifaceted intervention to promote beta-blocker use in heart failure.

BACKGROUND: Despite a survival benefit and guideline recommendation for beta-blockers in left ventricular systolic dysfunction, beta-blockers are underused in clinical practice. METHODS: Medical practices with > or = 15 patients with heart failure (HF) in the Duke Databank for Cardiovascular Disease (DDCD) were identified for a prospective, randomized study using a multifaceted intervention to improve beta-blocker use. Intervention practices received provider education, patient education materials, feedback on beta-blocker use of their patients with HF, and access to telephone consultation with an HF expert. The primary outcome was a comparison between intervention and control practices of the proportion of patients with HF self-reporting beta-blocker use on their first routine DDCD follow-up in the postintervention year. A random effects model was used for the analysis. RESULTS: Post intervention, 2631 patients (1701 in 23 intervention practices and 930 in 22 control practices) completed DDCD follow-up. No significant difference in the proportion of patients with HF reporting beta-blocker use was found in the intervention versus control groups (OR 1.16, 95% CI 0.94-1.43, P = .2), although more patients in the intervention group started a beta-blocker than stopped a beta-blocker during the study period (P = .02). CONCLUSIONS: This multifaceted intervention did not significantly increase the mean proportion of patients taking beta-blockers within practices exposed to the intervention, although favorable trends were observed. Further studies are needed to identify and evaluate strategies for translating evidence into clinical practice to reduce the global health burden associated with HF.

Adrenergic beta-Antagonists↗
PubMed2006

Trends in postoperative length of stay after bypass surgery.

BACKGROUND: Although single-site studies have reported reductions in coronary artery bypass graft (CABG) surgery length of stay (LOS) over the last 15 years, less information is available regarding overall temporal trends and interhospital variability. This study examined trends in postoperative LOS, associated rates of transfer at discharge and variation among hospitals in LOS at CABG hospitals in New York State. METHODS: Trends in postoperative LOS and transfers at discharge for 105,842 CABG patients treated in 30 hospitals in New York between 1992 and 1998 were first described graphically. Mixed models were then used to assess temporal trends and interhospital variability in LOS, accounting for differences in patient risk and within-hospital correlation in outcomes. Clinical and LOS data were obtained from the Cardiac Surgery Reporting System. Additional information was extracted from the New York Statewide Planning and Research Cooperative System. RESULTS: Postoperative LOS decreased 30% between 1992 and 1998 after adjusting for patient risk. A concurrent increase in the probability of nonacute patient transfers occurred over time, with the most pronounced increase in patients with stays exceeding 5 days. Underlying the downward trend in LOS was substantial interhospital variability that peaked in 1994 and remained significant in 1998. Stays were longer at hospitals located in New York City. CONCLUSIONS: The downward shift in LOS observed in the 1990s was achieved in part by an increase in nonacute care transfers, reflecting a shift in care setting. After decreasing trends in postoperative stays tapered off, significant variability among hospitals remained.

Aged↗
PubMed2005

Impact of mitral valve regurgitation evaluated by intraoperative transesophageal echocardiography on long-term outcomes after coronary artery bypass grafting.

BACKGROUND: It is unclear if mild or moderate mitral valve regurgitation (MR) should be repaired at the time of coronary artery bypass grafting (CABG). We sought to determine the long-term effect of uncorrected MR, measured by intraoperative transesophageal echocardiography (TEE), in CABG patients. METHODS AND RESULTS: Between May 1999 and September 2003, data were gathered for 3264 consecutive patients who underwent isolated CABG and had MR graded by intraoperative TEE. MR was graded on the following 5 levels: none, trace, mild, moderate, and severe. Patients who had severe MR or who underwent mitral valve surgery were eliminated from the analysis. The remaining patients were combined into the following 3 groups: none or trace, mild, and moderate MR. Preoperative and follow-up data were 99% complete. The median length of follow-up was 3.0 years. Multivariable analysis controlling for important preoperative risk factors was performed to determine predictors of death and death/hospitalization for heart failure. Increasing MR was a risk factor for death [hazard ratio (HR), 1.44; P<0.001] and death/heart failure hospitalization (HR, 1.34; P<0.01). When patients with moderate MR were eliminated from the analysis, mild MR was a risk factor for death (HR, 1.34; P=0.011) and death/hospitalization for heart failure (HR, 1.34; P<0.001). CONCLUSIONS: Even mild MR, identified by intraoperative TEE, predicts worse outcomes after CABG. Revascularization alone did not eliminate the negative long-term effects of mild MR. CABG patients with uncorrected mild or moderate MR are at increased risk for death and heart-failure hospitalization; consideration for surgical repair or more aggressive medical management and follow-up is warranted.

Aged↗
PubMed2005

Clinical predictors of major infections after cardiac surgery.

BACKGROUND: Major infections are infrequent but important complications of cardiac surgery. Predicting their occurrence is essential for future prevention. The objective of the current investigation was to create and validate a bedside scoring system to estimate patient risk for major infection (mediastinitis, thoracotomy or vein harvest site infection, or septicemia) after coronary artery bypass grafting. METHODS AND RESULTS: Using the Society of Thoracic Surgeons National Cardiac Database, we analyzed 331 429 coronary artery bypass grafting cases from January 1, 2002, to December 31, 2003, to identify risk factors for major infection. Using logistic regression, 2 models were generated and validated using split-sample validation: (1) One limited to preoperative characteristics (preop model) and (2) one model including both preoperative and intraoperative characteristics (combined model). Major infection occurred in 11 636 patients (3.51%) (25.1% mediastinitis, 32.6% saphenous harvest site, 35.0% septicemia, 0.5% thoracotomy, 6.8% multiple sites). Patients with major infection had significantly higher mortality (17.3% versus 3.0%, P<0.0001) and postoperative length of stay >14 days (47.0% versus 5.9%, P<0.0001) than patients without major infection. Both the preop model (c-index 0.697) and combined model (c-index: 0.708) successfully discriminated between high- and low-risk patients. A simplified risk scoring system of 12 variables accurately predicted risk for major infection. CONCLUSIONS: We identified and validated a model that can identify patients undergoing cardiac surgery who are at high risk for major infection. These high-risk patients may be targeted for perioperative intervention strategies to reduce rates of major infection.

Aged↗
PubMed2005

Risk-adjusted short- and long-term outcomes for on-pump versus off-pump coronary artery bypass surgery.

BACKGROUND: Surgeons have adopted off-pump coronary artery bypass grafting (OPCAB) in an effort to reduce the morbidity of surgical revascularization. However, long-term outcome of OPCAB compared with conventional coronary artery bypass grafting (CABG) remains poorly defined. METHODS AND RESULTS: Using logistic regression analysis and proportional hazards modeling, short-term and long-term outcomes (perioperative mortality and complications, risk-adjusted survival, and survival/freedom from revascularization) were investigated for patients who underwent OPCAB (641 patients) and CABG-cardiopulmonary bypass (5026 patients) from 1998 to 2003 at our institution. For these variables, follow-up was 98% complete. OPCAB patients were less likely to receive transfusion (odds ratio for OPCAB, 0.80; P=0.037), and there were trends toward improvement in other short-term outcomes compared with CABG-cardiopulmonary bypass. Long-term outcomes analysis demonstrated no difference in survival, but OPCAB patients were more likely to require repeat revascularization (OPCAB hazard ratio, 1.29; P=0.020). CONCLUSIONS: OPCAB patients were less likely to receive transfusion during their hospitalization for surgery but had higher risk for revascularization in follow-up. These results highlight the need for a large randomized, controlled trial to compare these 2 techniques.

Aged↗
PubMed2005

Surgeons' economic profiles: can we get the "right" answers?

Hospitals and payers use economic profiling to evaluate physician and surgeon performance. However, there is significant variation in the data sources and analytic methods that are used. We used information from a hospital's cardiac surgery and cost accounting information systems to create surgeon economic profiles. Three scenarios were examined: (1) surgeon modeled as fixed effect with no patient-mix adjustment; (2) surgeon modeled as fixed effect with patient-mix adjustment; (3) and surgeon modeled as random effect with patient-mix adjustment. We included 574 patients undergoing coronary artery bypass surgery at Baptist Medical Center, Oklahoma City, OK between July 1, 1995 and April 30, 1996. We found that profiles reporting unadjusted average surgeon costs may incorrectly identify high- and low-cost outliers. Adjusting for patient-mix differences and treating surgeons as random effects was the preferred approach. These results demonstrate the need for hospitals to reexamine their economic profiling methods.

Aged↗
PubMed2005

Immunotherapy for refractory pulmonary infection after adult cardiac surgery: immune dysregulation syndrome.

BACKGROUND AND AIM OF THE STUDY: Pulmonary dysfunction/multiorgan failure (PD/MF), usually due to refractory pulmonary infection, is an important cause of mortality and morbidity after cardiac operations. Moreover, the incidence of PD/MF may be increasing due to the emergence of antibiotic-resistant pathogens. METHODS: Fifteen consecutive patients (median age 69 years) who were developing antibiotic-refractory PD/MF were administered 24 g per day intravenous immunoglobulin (IV-IgG; Carimune) for five days. Ten patients had undergone complex valve surgery, and five coronary bypass. Preoperatively, 93% of patients had significant comorbidity, 73% presented acutely, 53% were hypoalbuminemic and 47% had antecedent acute pulmonary derangement. Clinical variables were assessed by retrospective chart review for three days prior to (-3) the start of IV-IgG (day 0) and for five days afterwards (+5). A postoperative morbidity index (PMI) was generated as a weighted sum of: worsening lung infiltrates (I); leukocytosis (L); pulmonary dysfunction (P); ventilator requirement (V); septic shock (S); renal (R), gastrointestinal (G), or hepatic (H) dysfunction; thrombocytopenia (T); and delirium (D). RESULTS: At day 0, all patients were refractory to major antibiotics, with morbidities of: 1-100%, L-93%, P-93%, V-60%, S-27%, R-67%, G-40%, H-13%, T-27%, and D-20%. Using regression analysis, IV-IgG administration was associated with a statistically significant fall in white blood count and improvement in PMI (p <0.006). Fourteen patients (93%) recovered uneventfully, and one patient (7%) died from progressive sepsis. No complications of IV-IgG therapy occurred. CONCLUSION: Given the high predicted mortality of PD/MF patients, these data suggest that IV-IgG is a safe and efficacious adjunct to antibiotics in this setting. Further studies, including a randomized trial and investigation of immunomodulatory mechanisms, seem indicated.

Adult↗
PubMed2004

Cost analysis of aprotinin for coronary artery bypass patients: analysis of the randomized trials.

BACKGROUND: The full kallikrein-inhibiting dose of aprotinin has been shown to reduce blood loss, transfusion requirements, and the systemic inflammatory response associated with cardiopulmonary bypass graft surgery (CABG). A half-dose regimen, although having a reduced delivery cost, inhibits plasmin and fibrinolysis without substantially effecting kallikrein-mediated inflammation associated with bypass surgery. The differing pharmacologic effects of the two regimens impact the decision-making process. The current study assessed the medical cost offset of full-dose and half-dose aprotinin from short- and long-term perspectives to provide a rational decision-making framework for clinicians. METHODS: To estimate CABG admission costs, resource utilization and clinical data from aprotinin clinical trials were combined with unit costs estimated from a Duke University-based cost model. Lifetime medical costs of stroke and acute myocardial infarction were based on previous research. RESULTS: Relative to placebo, the differences in total perioperative cost for primary CABG patients receiving full-dose or half-dose aprotinin were not significant. When lifetime medical costs of complications were considered, total costs in full-dose and half-dose aprotinin-treated patients were not different relative to that of placebo. Total perioperative cost was significantly lower for repeat CABG patients treated with aprotinin, with savings of $2,058 for full-dose and $2,122 for half-dose patients when compared with placebo. Taking lifetime costs of stroke and acute myocardial infarction into consideration, the cost savings estimates were $6,044 for full-dose patients and $4,483 for half-dose patients, due to substantially higher lifetime stroke costs incurred by the placebo patients. CONCLUSIONS: Using this cost model, use of full-dose and half-dose aprotinin in primary CABG patients was cost neutral during hospital admission, whereas both dosing regimens were significantly cost saving in reoperative CABG patients. Additional lifetime cost savings were realized relative to placebo due to reduced complication costs, particularly with the full-dose regimen. As the full kallikrein-inhibiting dose of aprotinin has been shown to be safe and effective, the current results support its use in both primary and repeat CABG surgery. No demonstrable economic advantage was observed with the half-dose aprotinin regimen.

Adult↗
PubMed2004

Laparoscopic appendectomy in the elderly.

BACKGROUND: Evidence suggests that laparoscopic appendectomy (LA) has advantages over open appendectomy (OA) in the treatment of appendicitis. It remains, however, unclear whether LA is indicated in the elderly patient population. METHODS: Patients with primary International Classification of Diseases, revision 9, procedure codes for LA (n=32406 patients) and OA (n=112884 patients) were selected from the 1998, 1999, and 2000 Nationwide Inpatient Samples. The end points that were under investigation were the length of hospital stay, the rate of routine discharge, and in-hospital morbidity and mortality rates. Multiple linear and logistic regression analyses were performed to assess the risk-adjusted association between the surgery type and the patient outcomes. Stratified analyses were performed according to age (65 years and older; less than 65 years old) and to the presence of appendiceal perforation or abscess. RESULTS: After risk adjustment, patients who underwent LA had a significantly shorter mean length of stay (LA, 2.45 days; OA, 3.71 days; P <. 0001), higher rate of routine discharge (odds ratio, 2.80; P <.0001), lower overall complication rate (odds ratio, 0.92; P=.03), and mortality rate (odds ratio, 0.23; P=.001) compared with OA patients. Similar benefits of LA were found in the strata of patients who were less than 65 years old, in elderly patients, and in patients with appendiceal perforation or abscess. CONCLUSION: LA has statistically significant advantages over OA with respect to the length of hospital stay, the rate of routine discharge, and postoperative morbidity and mortality rates for patients who are less than 65 years old, in elderly patients, and in patients with appendiceal abscess or perforation.

Abdominal Abscess↗
PubMed2004

Laparoscopic versus open appendectomy: outcomes comparison based on a large administrative database.

OBJECTIVE: To compare length of hospital stay, in-hospital complications, in-hospital mortality, and rate of routine discharge between laparoscopic and open appendectomy based on a representative, nationwide database. SUMMARY BACKGROUND DATA: Numerous single-institutional randomized clinical trials have assessed the efficacy of laparoscopic and open appendectomy. The results, however, are conflicting, and a consensus concerning the relative advantages of each procedure has not yet been reached. METHODS: Patients with primary ICD-9 procedure codes for laparoscopic and open appendectomy were selected from the 1997 Nationwide Inpatient Sample, a database that approximates 20% of all US community hospital discharges. Multiple linear and logistic regression analyses were used to assess the risk-adjusted endpoints. RESULTS: Discharge abstracts of 43757 patients were used for our analyses. 7618 patients (17.4%) underwent laparoscopic and 36139 patients (82.6%) open appendectomy. Patients had an average age of 30.7 years and were predominantly white (58.1%) and male (58.6%). After adjusting for other covariates, laparoscopic appendectomy was associated with shorter median hospital stay (laparoscopic appendectomy: 2.06 days, open appendectomy: 2.88 days, P < 0.0001), lower rate of infections (odds ratio [OR] = 0.5 [0.38, 0.66], P < 0.0001), decreased gastrointestinal complications (OR = 0.8 [0.68, 0.96], P = 0.02), lower overall complications (OR = 0.84 [0.75, 0.94], P = 0.002), and higher rate of routine discharge (OR = 3.22 [2.47, 4.46], P < 0.0001). CONCLUSIONS: Laparoscopic appendectomy has significant advantages over open appendectomy with respect to length of hospital stay, rate of routine discharge, and postoperative in-hospital morbidity.

Adult↗
PubMed2002

Patient-reported frequency of taking aspirin in a population with coronary artery disease.

Despite the established benefits of antiplatelet agents in coronary artery disease (CAD), many appropriate patients are not receiving them. We investigated the prevalence of and factors associated with aspirin use and nonuse within a large referral population with CAD. The goal was to identify an approach to increase the use of antiplatelet agents by such patients. We surveyed a subset (n = 2,694) of a large CAD referral population (n = 16,174) to determine the use of aspirin and factors associated with its use or nonuse. The subset was made up of all of the CAD referral population who were considered nonusers of aspirin and a 5% sample of those considered aspirin users. We then extrapolated survey data to the overall population to estimate how many eligible patients were not taking antiplatelet agents. In all, 1,626 (63%) of the surviving patients responded to the survey. Of these, 948 (58%) reported taking aspirin, and 678 (42%) reported no aspirin use. The extrapolated rate of aspirin use in the overall population was 85%. Of 2,367 nonusers, 998 (42%, or 6% of the overall cohort) were eligible for antiplatelet agents but were not taking such therapy. Although the rate of aspirin use in this population was higher than previously reported, an estimated 6% of eligible patients were not receiving antiplatelet therapy.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2002

Underuse of aspirin in a referral population with documented coronary artery disease.

Despite substantial evidence that antiplatelet therapy saves lives and reduces adverse events in patients with coronary artery disease (CAD), use of the most widely available and lowest cost antiplatelet agent, aspirin, continues to be disappointingly low. In a large database of patients with known CAD, we (1) explored trends in the use of aspirin over time, (2) characterized patients most likely to take aspirin regularly, and (3) estimated the effectiveness of aspirin use by examining long-term outcomes. Using patients entered in the Duke Databank for Cardiovascular Diseases, we explored the use of aspirin from 1969 to 1999. More than 25,000 patients were sent a questionnaire that included several questions about medication use, including 1 question specifically about aspirin. Patients who failed to respond to the questionnaire received a follow-up telephone call. Aspirin use increased substantially over the most recent 4 years in the study, from 59% in 1995 to 81% in 1999. Predictors of aspirin use included younger age, male sex, being a nonsmoker, and having had a myocardial infarction or revascularization procedure. Patients who never took aspirin had a risk ratio for death of 1.85 compared with patients who regularly took aspirin. Despite the well-known beneficial effects of aspirin, too many patients without contraindications to aspirin fail to take it regularly. The health care system currently lacks effective methods to ensure that patients who have CAD have adequate follow-up concerning aspirin use.

Adult↗