E. Francis Cook

Derivation and Prospective Validation of a Simple Index for Prediction of Cardiac Risk of Major Noncardiac Surgery

BACKGROUND Cardiac complications are important causes of morbidity after noncardiac surgery. The purpose of this prospective cohort study was to develop and validate an index for risk of cardiac complications. METHODS AND RESULTS We studied 4315 patients aged > or = 50 years undergoing elective major noncardiac procedures in a tertiary-care teaching hospital. The main outcome measures were major cardiac complications. Major cardiac complications occurred in 56 (2%) of 2893 patients assigned to the derivation cohort. Six independent predictors of complications were identified and included in a Revised Cardiac Risk Index: high-risk type of surgery, history of ischemic heart disease, history of congestive heart failure, history of cerebrovascular disease, preoperative treatment with insulin, and preoperative serum creatinine >2.0 mg/dL. Rates of major cardiac complication with 0, 1, 2, or > or = 3 of these factors were 0.5%, 1.3%, 4%, and 9%, respectively, in the derivation cohort and 0.4%, 0.9%, 7%, and 11%, respectively, among 1422 patients in the validation cohort. Receiver operating characteristic curve analysis in the validation cohort indicated that the diagnostic performance of the Revised Cardiac Risk Index was superior to other published risk-prediction indexes. CONCLUSIONS In stable patients undergoing nonurgent major noncardiac surgery, this index can identify patients at higher risk for complications. This index may be useful for identification of candidates for further risk stratification with noninvasive technologies or other management strategies, as well as low-risk patients in whom additional evaluation is unlikely to be helpful.

A computer protocol to predict myocardial infarction in emergency department patients with chest pain.

To achieve more appropriate triage to the coronary care unit of patients presenting with acute chest pain, we used clinical data on 1379 patients at two hospitals to construct a simple computer protocol to predict the presence of myocardial infarction. When we tested this protocol prospectively in 4770 patients at two university hospitals and four community hospitals, the computer-derived protocol had a significantly higher specificity (74 vs. 71 percent) in predicting the absence of infarction than physicians deciding whether to admit patients to the coronary care unit, and it had a similar sensitivity in detecting the presence of infarction (88.0 vs. 87.8 percent). Decisions based solely on the computer protocol would have reduced the admission of patients without infarction to the coronary care unit by 11.5 percent without adversely affecting the admission of patients in whom emergent complications developed that required intensive care. Although this protocol should not be used to override careful clinical judgment in individual cases, the computer protocol for the most part yields accurate estimates of the probability of myocardial infarction. Decisions about admission to the coronary care unit based on the protocol would have been as effective as those actually made by the unaided physicians who cared for the patients, and less costly. Whether physicians who are aided by the protocol perform better than unaided physicians cannot be determined without further study.

Clinical characteristics and natural history of patients with acute myocardial infarction sent home from the emergency room

In a prospective multicenter investigation of emergency room patients with acute chest pain, physicians admitted 96% of patients with acute myocardial infarction (AMI) and discharged 4%. Of 35 patients who were sent home with AMI, only 11 (31%) returned to the same hospital because of persistent symptoms. Compared with a control group of 105 randomly selected patients with AMI who were admitted from the emergency room, patients in whom AMI was missed were significantly younger, had less typical symptoms and were less likely to to have had prior AMI or angina or to have electrocardiographic evidence of ischemia or infarction not known to be old. Despite the less typical presentations of patients in whom AMI was missed, after controlling for age and sex, the short-term mortality rate was significantly higher among patients in whom AMI was missed but in whom it was detected through our follow-up procedures than in admitted AMI patients. As determined by independent reviewers, 49% of the missed AMIs could have been diagnosed through improved electrocardiographic reading skills or by admission of patients with recognized ischemic pain at rest or ischemic electrocardiographic changes not known to be old.

Evaluation and outcome of emergency room patients with transient loss of consciousness.

We identified 198 patients who presented to our emergency room with transient loss of consciousness. Seizures (29 percent of patients) and vasovagal/psychogenic episodes (40 percent of patients) were the most common presumptive causes of loss of consciousness, but the cause of loss of consciousness remained uncertain even at follow-up in 11 +/- 6 months in 13 percent of the patients. The history and physical examinations were sufficient for diagnosis in 85 percent of the patients in whom a diagnosis could be established. These data guided inpatient and outpatient with potentially dangerous causes of loss of consciousness except for one patient who had pulmonary embolism. In selected patient, diagnostic tests such as blood chemistries (three patients), electrocardiograms (four patients) electroencephalograms (three patients), and Holter monitoring (four patients) provided crucial information, and CT scans identified new brain tumors in four patients with focal neurologic presentations. At the time of follow-up, 7.5 percent of patients had suffered either major morbidity or death related to the cause of the index episode of loss of consciousness. Patients with cardiac causes represented a high risk (33 percent) group for such poor outcome, whereas patients who were under age 30, or who were under age 70 and had loss of consciousness on a vasovagal/psychogenic or unknown basis, constituted a low risk (1 percent) subgroup.

Is the Professional Satisfaction of General Internists Associated with Patient Satisfaction

AbstractBACKGROUND: The growth of managed care has raised a number of concerns about patient and physician satisfaction. An association between physicians’ professional satisfaction and the satisfaction of their patients could suggest new types of organizational interventions to improve the satisfaction of both. OBJECTIVE: To examine the relation between the satisfaction of general internists and their patients. DESIGN: Cross-sectional surveys of patients and physicians. SETTING: Eleven academically affiliated general internal medicine practices in the greater-Boston area. PARTICIPANTS: A random sample of English-speaking and Spanish-speaking patients (n=2,620) with at least one visit to their physician (n=166) during the preceding year. MEASUREMENTS: Patients’ overall satisfaction with their health care, and their satisfaction with their most recent physician visit. MAIN RESULTS: After adjustment, the patients of physicians who rated themselves to be very or extremely satisfied with their work had higher scores for overall satisfaction with their health care (regression coefficient 2.10; 95% confidence interval 0.73–3.48), and for satisfaction with their most recent physician visit (regression coefficient 1.23; 95% confidence interval 0.26–2.21). In addition, younger patients, those with better overall health status, and those cared for by a physician who worked part-time were significantly more likely to report better satisfaction with both measures. Minority patients and those with managed care insurance also reported lower overal satisfaction. CONCLUSIONS: The patients of physicians who have higher professional satisfaction may themselves be more satisfied with their care. Further research will need to consider factors that may mediate the relation between patient and physician satisfaction.

Drug Complications in Outpatients

OBJECTIVE: Outpatient drug complications have not been well studied. We sought to assess the incidence and characteristics of outpatient drug complications, identify their clinical and nonclinical correlates, and evaluate their impact on patient satisfaction. DESIGN: Retrospective chart reviews and patient surveys. SETTING: Eleven Boston-area ambulatory clinics. PATIENTS: We randomly selected 2,248 outpatients, 20 to 75 years old. MEASUREMENTS AND MAIN RESULTS: Among 2,248 patients reporting prescription drug use, 394 (18%) reported a drug complication. In contrast, chart review revealed an adverse drug event in only 64 patients (3%). In univariate analyses, significant correlates of patient-reported drug complications were number of medical problems, number of medications, renal disease, failure to explain side effects before treatment, lower medication compliance, and primary language other than English or Spanish. In multivariate analysis, independent correlates were number of medical problems (odds ratio [OR] 1.17; 95% confidence interval [95% CI] 1.05 to 1.30), failure to explain side effects (OR 1.65; 95% CI, 1.16 to 2.35), and primary language other than English or Spanish (OR 1.40; 95% CI, 1.01 to 1.95). Patient satisfaction was lower among patients who reported drug complications (P < .0001). In addition, 48% of those reporting drug complications sought medical attention and 49% experienced worry or discomfort. On chart review, 3 (5%) of the patients with an adverse drug event required hospitalization and 8 (13%) had a documented previous reaction to the causative drug. CONCLUSIONS: Drug complications in the ambulatory setting were common, although most were not documented in the medical record. These complications increased use of the medical system and correlated with dissatisfaction with care. Our results indicate a need for better communication about potential side effects of medications, especially for patients with multiple medical problems.

Prognostic Value of Quantitative Contrast-Enhanced Cardiovascular Magnetic Resonance for the Evaluation of Sudden Death Risk in Patients With Hypertrophic Cardiomyopathy

Background— Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden death in the young, although not all patients eligible for sudden death prevention with an implantable cardioverter-defibrillator are identified. Contrast-enhanced cardiovascular magnetic resonance with late gadolinium enhancement (LGE) has emerged as an in vivo marker of myocardial fibrosis, although its role in stratifying sudden death risk in subgroups of HCM patients remains incompletely understood. Methods and Results— We assessed the relation between LGE and cardiovascular outcomes in 1293 HCM patients referred for cardiovascular magnetic resonance and followed up for a median of 3.3 years. Sudden cardiac death (SCD) events (including appropriate defibrillator interventions) occurred in 37 patients (3%). A continuous relationship was evident between LGE by percent left ventricular mass and SCD event risk in HCM patients (P=0.001). Extent of LGE was associated with an increased risk of SCD events (adjusted hazard ratio, 1.46/10% increase in LGE; P=0.002), even after adjustment for other relevant disease variables. LGE of ≥15% of LV mass demonstrated a 2-fold increase in SCD event risk in those patients otherwise considered to be at lower risk, with an estimated likelihood for SCD events of 6% at 5 years. Performance of the SCD event risk model was enhanced by LGE (net reclassification index, 12.9%; 95% confidence interval, 0.3–38.3). Absence of LGE was associated with lower risk for SCD events (adjusted hazard ratio, 0.39; P=0.02). Extent of LGE also predicted the development of end-stage HCM with systolic dysfunction (adjusted hazard ratio, 1.80/10% increase in LGE; P<0.03). Conclusions— Extensive LGE measured by quantitative contrast enhanced CMR provides additional information for assessing SCD event risk among HCM patients, particularly patients otherwise judged to be at low risk.

The association of intraoperative factors with the development of postoperative delirium

PURPOSE To examine the association of intraoperative factors, including route of anesthesia, hemodynamic complications, and blood loss, with the development of postoperative delirium. PATIENTS AND METHODS We studied 1,341 patients 50 years of age and older admitted for major elective noncardiac surgery at an academic medical center. Data on route of anesthesia, intraoperative hypotension, bradycardia and tachycardia, blood loss, number of blood transfusions, and lowest postoperative hematocrit were obtained from the medical record. Delirium was diagnosed by using daily interviews with the Confusion Assessment Method, as well as from the medical record and the hospitals nursing intensity index. RESULTS Postoperative delirium occurred in 117 (9%) patients. Route of anesthesia and intraoperative hemodynamic complications were not associated with delirium. Delirium was associated with greater intraoperative blood loss, more postoperative blood transfusions, and postoperative hematocrit <30%. After adjusting for preoperative risk factors, postoperative hematocrit <30% was associated with an increased risk of delirium (odds ratio = 1.7, 95% confidence interval 1.1-2.7). CONCLUSIONS Further study is required to determine whether transfusion to keep postoperative hematocrit above 30% can reduce the incidence of postoperative delirium.

Identification and preliminary validation of predictors of major bleeding in hospitalized patients starting anticoagulant therapy

Among 617 hospitalized patients who started long-term anticoagulant therapy, major bleeding developed before discharge in 28 (5 percent) and minor bleeding in another 38 (6 percent), with daily incidence rates of 0.4 and 0.5 percent, respectively. The most common site of bleeding was gastrointestinal, and one patient died from bleeding. Four independent risk factors for major in-hospital bleeding were identified and weighted using multivariate discriminant analysis in a randomly chosen group of 411 patients: co-morbid conditions other than the indication for anticoagulant therapy (specific signs of heart, liver, or kidney dysfunction, cancer, and severe anemia); the use of heparin to begin therapy in patients age 60 years or older; the intensity of therapy (measured by the maximal prothrombin time or partial thromboplastin time); and liver dysfunction that worsened during treatment. These findings were validated in an independent testing group of 206 patients; the risk factors identified 151 patients at low (1 percent) risk of major bleeding, 33 at moderate (6 percent) risk, and 22 at high (23 percent) risk. The accuracy and clinical impact of this prediction rule should be evaluated further in other hospitals.

Clinical Characteristics and Outcome of Acute Myocardial Infarction in Patients with Initially Normal or Nonspecific Electrocardiograms (A Report from the Multicenter Chest Pain Study)

To determine the prevalence and characteristics of acute myocardial infarction (AMI) patients who present to emergency departments with normal or nonspecific electrocardiograms (ECGs), data were analyzed from 7,115 consecutive patients in the Multicenter Chest Pain Study. AMI patients with normal or nonspecific initial ECGs (n = 107) were less likely to have a past history of coronary artery disease or to be diaphoretic on presentation (p less than 0.01) than AMI patients with initial ECGs highly suggestive of AMI (n = 811). The overall probability of AMI among patients with chest pain and initially normal or nonspecific ECGs was 3%, but ranged from less than 1 to 17% depending on the patients age and sex and whether the patient had pressure-type pain or pain radiating to the shoulder, neck or arms. Among initially admitted patients, the time elapsed between onset of pain and presentation was similar in both groups. However, the time between onset of pain and definitive diagnosis of AMI by enzymes or clinical course was longer in patients with initially normal or nonspecific electrocardiograms (8.3 vs 7.5 hours, p less than 0.05), their peak creatine kinase levels were lower (mean 643 vs 1,032 mg/dl, p less than 0.001) and their mortality was slightly lower (6 vs 12%, p = 0.10). These findings suggest that AMI patients with initially normal or nonspecific ECGs may have a less severe short-term clinical outcome.