Quantifying the usefulness of CT in evaluating seniors with abdominal pain.

OBJECTIVES: (1) Determine if older patients with abdominal pain who receive emergency department (ED) abdominal CT have changes in diagnosis and/or disposition more often than similar patients without CT; (2) compare physician confidence in diagnosis and disposition for patients with versus without CT; (3) document factors that most influence physician's decision to order abdominal CT in this population. METHODS: ED patients 60 years of age or older, with acute non-traumatic abdominal pain were enrolled over a 6-week period. Physicians documented a preliminary and final ED diagnosis and disposition, along with pre- and post-evaluation confidence levels. Decision to order CT, along with clinical information most influencing that decision, was noted. Physician confidence levels and percent change in diagnosis and disposition were compared for patients with versus without CT. RESULTS: One hundred and twenty-six patients comprised study sample. Abdominal CT rate was 59% (95%CI, 50-67%). CT was associated with an increased change in diagnosis (46%; 95%CI, 4-58% versus 29%; 95%CI, 16-42%), but no change in disposition between patients with versus without CT. Preliminary diagnostic confidence was lower for EPs who ordered a CT than for those who did not (p<0.001). Patient history most influenced ordering CT, whereas prior lab/imaging results most influenced not ordering CT. CONCLUSION: Patients with CT had a change in diagnosis more often than those without. Preliminary diagnostic confidence was lower in CT group. Percent change in disposition did not differ between groups. Physicians most often ordered CT based on history and did not order CT when other diagnostic evaluation supported a specific diagnosis.

Effects of implementing computerized practitioner order entry and nursing documentation on nursing workflow in an emergency department.

Nurses'perceptions of effective use of their time are critical to the successful implementation of information system changes. We examined the effects of implementing computerized practitioner order entry and nursing documentation in our emergency department with an anonymous survey of nurses and repeated time-motion studies. Emergency care nurses were positive about effects of CPOE, reporting needing less time to complete medication, laboratory, and radiology orders and less time spent clarifying orders. Their perceptions of time spent were congruent with observations from time-motion studies where combined computer-and-paper time and direct-patient-care time did not change significantly. Nurses also reported supplementing template options with free text, and those who were more comfortable using computers reported supplementing template options more often than their counterparts, suggesting that assessments of users' expertise in computer use may influence their ability to maximize their use of the functionality of emergency department information systems.

Etiology and clinical course of abdominal pain in senior patients: a prospective, multicenter study.

BACKGROUND: The authors describe the epidemiology and clinical course of older persons examined in emergency departments (EDs) for abdominal pain. METHODS: This was a prospective, multicenter, observational study of older persons (>or=60 years) examined in participating EDs for nontraumatic abdominal pain. Medical records were reviewed for demographics, ED diagnoses, findings of radiographic imaging, disposition, operative procedures, length of hospitalization, and final diagnoses. Patients were interviewed at 2 weeks to determine clinical course, final diagnoses, and mortality status. The authors compared ED diagnoses with final diagnoses, reporting the percentage change in aggregate and for the 12 most common diagnoses. RESULTS: Of 360 patients (mean age, 73.2+/- 8.8 years; 66% women; 51% white) who met selection criteria, 209 (58%) were admitted to the hospital and 63 (18%) required surgery or an invasive procedure. For patients with complete follow-up information (n=337), 37 (11%) had repeated ED visits and 23 (7%) were readmitted to the hospital. The case-fatality rate was 5%. Leading causes of abdominal pain were nonspecific (14.8%), urinary tract infection (8.6%), bowel obstruction (8%), gastroenteritis (6.8%), and diverticulitis (6.5%). The ED and final diagnoses matched 82% of the time. Older patients had higher mortality rates (odds ratio, 4.4; 95% confidence interval, 1.4--14) and lower diagnostic concordance rates (76% vs 87%; p=.01). Study limitations include inability to enroll all eligible persons and possible inaccuracies in participant-reported follow-up interviews. CONCLUSIONS: Abdominal pain in older patients should be investigated thoroughly as, in this study, nearly 60% of patients were hospitalized, 20% underwent operative or invasive procedures, 10% had return ED visits, and 5% died within a 2-week follow-up period.

The use of abdominal computed tomography in older ED patients with acute abdominal pain.

The objectives of this study were to determine the prevalence of use of abdominal computed tomography (CT) in older ED patients with acute nontraumatic abdominal pain, describe the most common diagnostic CT findings, and determine the proportion of diagnostic CT results. This was a prospective, observational, multicenter study of 337 patients 60 years or older. History was obtained prospectively; charts were reviewed for radiographic findings, dispositions, diagnoses, and clinical course, and patients were followed up at 2 weeks for additional information. The prevalence of use of abdominal CT was 37%. The most common diagnostic findings were diverticulitis (18%), bowel obstruction (18%), nephrolithiasis (10%), and gallbladder disease (10%). Eight percent of patients had findings suggestive of neoplasm. Overall, 57% of CT results were diagnostic (95% confidence interval [CI], 49%-66%), 75% (95% CI, 63%-84%) for patients requiring acute medical or surgical intervention, and 85% (95% CI, 62%-97%) for patients requiring acute surgical intervention. CT use is highly prevalent in older ED patients with acute abdominal pain. CT results are often diagnostic, especially for patients with emergent conditions.

Effect of warfarin nonadherence on control of the International Normalized Ratio.

OBJECTIVE: The frequency and causes of ab- errant International Normalized Ratios (INRs) in warfarin recipients and the percentage explainable by warfarin nonadherence were studied. METHODS: The medical records of patients whose warfarin therapy was monitored by a telephone-based anticoagulation service in a Midwestern urban hospital between March 2000 and March 2001 were reviewed for causes of out-of-range INRs, the percentage of out-of-range INRs attributable to warfarin nonadherence, and demographic and clinical variables predictive of nonadherence. RESULTS: Data from 347 patients were studied. The cohort yielded 4305 INRs, of which 1002 (23%) were out of range (lower than 1.8 or higher than 3.4). Thirty-six percent of the out-of-range INRs were due to warfarin or dietary nonadherence, 9% were due to medical systems problems (including drug interactions), 18% were due to a change in clinical status, and 38% were idiopathic. Age younger than 65 years, age greater than 80 years, and living closer to the laboratory were predictive of warfarin nonadherence. CONCLUSION: Warfarin nonadherence was the most common cause of explainable aberrant INRs in patients taking warfarin. Age younger than 65 years, age greater than 80 years, and living close to the laboratory were predictive of warfarin nonadherence.

Colonic ischemia: an under-recognized cause of lower gastrointestinal bleeding.

We described signs and symptoms of patients who present to an Emergency Department (ED) with intestinal ischemia and compare clinical course and outcomes of patients with mesenteric vs. colonic ischemia. We retrospectively reviewed charts of 100 patients discharged from our hospital with an ICD-9 code for mesenteric or intestinal ischemia. Compared to patients with mesenteric ischemia, those with colonic ischemia were older (61 vs. 77 years, respectively; p = 0.002), were more likely to present with gastrointestinal (GI) bleeding (11 vs. 90%, respectively; p < 0.001), but were less likely to report abdominal pain as their primary complaint (89% vs. 10%, respectively; p < 0.001) or to receive a correct ED diagnosis (75% vs. 9%, respectively; p < 0.001). Patients with colonic ischemia frequently presented with gross GI bleeding, and were often misdiagnosed in the ED. For timely treatment of a potentially serious condition, the diagnosis of intestinal ischemia should be considered in ED patients presenting with GI bleeding and appropriate risk factors.

Use of pharmacogenetics and clinical factors to predict the maintenance dose of warfarin.

Knowledge of pharmacogenetics may help clinicians predict their patients' therapeutic dose of warfarin, thereby decreasing the risk of bleeding during warfarin initiation. Our goal was to use pharmacogenetics to develop an algorithm that uses genetic, clinical, and demographic factors to estimate the warfarin dose a priori. We collected a blood sample, demographic variables, laboratory values, smoking status, names of medications, and dietary history from 369 patients who were taking a maintenance dose of warfarin. Using polymerase chain reaction, we genotyped each participant for the presence of 8 polymorphisms in the cytochrome P450 2C9 system. Using multiple regression, we quantified the association between warfarin dose and all factors. Advanced age, lower body surface area (BSA), and the presence of cytochrome P450 2C9 *2 or *3 single nucleotide polymorphisms were strongly associated (P < 0.001) with lower warfarin dose: the maintenance dose decreased by 8% per decade of age, by 13% per standard deviation decrease in BSA, by 19% per 2C9*2 allele, and by 30% per 2C9*3 allele. Warfarin doses were 29% lower in patients who took amiodarone, 12% lower in patients who took simvastatin, 21% lower in patients whose target INR was 2.5 rather than 3.0, and 11% lower in white rather than African-American participants (P < 0.05 for these comparisons). An algorithm that included these factors and one of borderline significance (sex), explained 39% of the variance in the maintenance warfarin dose. Use of this pharmacogenetic model had potential to prevent patients from being overdosed when initiating warfarin: we estimate that only 24 (6.5%) patients would have been over- dosed by >2 mg/day with pharmacogenetic dosing compared to 59 (16%) patients who would have been overdosed if they had been prescribed the empirical dose of 5 mg/day (P < 0.001). In conclusion, the maintenance warfarin dose can be estimated from demographic, clinical, and pharmacogenetic factors that can be obtained at the time of warfarin initiation.

Warfarin dose reduction vs watchful waiting for mild elevations in the international normalized ratio.

BACKGROUND: Whether clinicians should decrease the warfarin dose in response to a mild, asymptomatic elevation in the international normalized ratio (INR) is unknown. OBJECTIVES: The study objectives were as follows: (1) to evaluate the safety of an anticoagulation service (ACS) policy advocating that the warfarin dose not be changed for isolated, asymptomatic INRs of < or = 3.4; (2) to compare the dosing strategies of an ACS and primary care providers (PCPs); and (3) to quantify the relationship between reduction of the warfarin dose and the subsequent fall in the INR. DESIGN AND SETTING: Randomized controlled study of health maintenance organization outpatients who were receiving warfarin. PATIENTS: We identified 231 patients with a target INR of 2.5 and an isolated, asymptomatic INR between 3.2 and 3.4. Our ACS monitored 103 of the patients; PCPs monitored the remaining 128 patients. MEASUREMENTS: From all 231 patients, we obtained INRs and warfarin dosing history. From the 103 ACS enrollees, we also recorded adverse events. RESULTS: One ACS patient had epistaxis in the 30 days after the elevated INR. Twenty-three percent of ACS enrollees and 47% of PCP patients reduced their warfarin dose (p < 0.001). The median follow-up INRs were similar in both cohorts: 2.7 in the ACS enrollees and 2.6 in the PCP patients. However, in a subgroup analysis of 190 patients who presented with an INR of 3.2 or 3.3, ACS enrollees were more likely to have a follow-up INR in the range of 2 to 3 (p = 0.03). The median follow-up INR was 2.7 in 148 patients who maintained their warfarin dose, 2.5 in 77 patients who decreased their dose by 1 to 20%, and 1.7 in 6 patients who decreased their dose by 21 to 43% (p < 0.001). CONCLUSIONS: These findings support maintaining the same warfarin dose in asymptomatic patients with an INR of < or = 3.3, and reducing the dose for patients who have a greater INR or an increased risk of hemorrhage. Warfarin dose reductions > 20% should be avoided for mildly elevated INRs.

Substitution of generic warfarin for Coumadin in an HMO setting.

BACKGROUND: Substitution of generic warfarin for Coumadin presents safety concerns due to warfarin's narrow therapeutic index and because a prior generic formulation was removed from the US market after it was associated with adverse events. OBJECTIVE: To determine whether a health maintenance organization (HMO) can add generic warfarin to its formulary without adversely affecting warfarin management or increasing adverse events. DESIGN: In a prospective, observational study, an HMO that formerly dispensed only Coumadin added a generic warfarin preparation (Barr Laboratories, Pomona, NY) to its formulary. SETTING: An anticoagulation service (ACS) affiliated with an HMO that was based in St. Louis, MO. PARTICIPANTS: The cohort consisted of 182 enrollees in the ACS as of May 1, 1999. At the start of the study, these participants were taking Coumadin; by October 31, 2000, all had switched to Barr warfarin. MEASUREMENTS AND MAIN RESULTS: We collected data 8 months prior to and 10 months after the introduction of generic warfarin for the following endpoints: international normalized ratio (INR) control, frequency of INR monitoring, number of dose changes, and rate of thrombotic and hemorrhagic events. Statistical process control charts were used to differentiate between random variation in the endpoints and changes due to different warfarin formulations, and we used the Wilcoxon signed-rank test to look for a change in any endpoint after patients changed to generic warfarin. No significant differences were found in any endpoint. CONCLUSIONS: Substitution of Barr warfarin for Coumadin did not significantly affect INR control, warfarin management, or adverse events. Our findings suggest that HMOs can safely substitute at least 1 generic formulation of warfarin without extra monitoring.