Prospective multicenter evaluation of the pulmonary embolism rule-out criteria.

BACKGROUND: Over-investigation of low-risk patients with suspected pulmonary embolism (PE) represents a growing problem. The combination of gestalt estimate of low suspicion for PE, together with the PE rule-out criteria [PERC(-): age < 50 years, pulse < 100 beats min(-1), SaO(2) >or= 95%, no hemoptysis, no estrogen use, no surgery/trauma requiring hospitalization within 4 weeks, no prior venous thromboembolism (VTE), and no unilateral leg swelling], may reduce speculative testing for PE. We hypothesized that low suspicion and PERC(-) would predict a post-test probability of VTE(+) or death below 2.0%. METHODS: We enrolled outpatients with suspected PE in 13 emergency departments. Clinicians completed a 72-field, web-based data form at the time of test order. Low suspicion required a gestalt pretest probability estimate of <15%. The main outcome was the composite of image-proven VTE(+) or death from any cause within 45 days. RESULTS: We enrolled 8138 patients, 85% of whom had a chief complaint of either dyspnea or chest pain. Clinicians reported a low suspicion for PE, together with PERC(-), in 1666 patients (20%). At initial testing and within 45 days, 561 patients (6.9%, 95% confidence interval 6.5-7.6) were VTE(+), and 56 others died. Among the low suspicion and PERC(-) patients, 15 were VTE(+) and one other patient died, yielding a false-negative rate of 16/1666 (1.0%, 0.6-1.6%). As a diagnostic test, low suspicion and PERC(-) had a sensitivity of 97.4% (95.8-98.5%) and a specificity of 21.9% (21.0-22.9%). CONCLUSIONS: The combination of gestalt estimate of low suspicion for PE and PERC(-) reduces the probability of VTE to below 2% in about 20% of outpatients with suspected PE.

Clinical criteria to prevent unnecessary diagnostic testing in emergency department patients with suspected pulmonary embolism.

Overuse of the d-dimer to screen for possible pulmonary embolism (PE) can have negative consequences. This study derives and tests clinical criteria to justify not ordering a d-dimer. The test threshold was estimated at 1.8% using the method of Pauker and Kassirer. The PE rule-out criteria were derived from logistic regression analysis with stepwise backward elimination of 21 variables collected on 3148 emergency department patients evaluated for PE at 10 US hospitals. Eight variables were included in a block rule: Age < 50 years, pulse < 100 bpm, SaO(2) > 94%, no unilateral leg swelling, no hemoptysis, no recent trauma or surgery, no prior PE or DVT, no hormone use. The rule was then prospectively tested in a low-risk group (1427 patients from two hospitals initially tested for PE with a d-dimer) and a very low-risk group (convenience sample of 382 patients with chief complaint of dyspnea, PE not suspected). The prevalence of PE was 8% (95% confidence interval: 7-9%) in the low-risk group and 2% (1-4%) in the very low-risk group on longitudinal follow-up. Application of the rule in the low-risk and very low-risk populations yielded sensitivities of 96% and 100% and specificities of 27% and 15%, respectively. The prevalence of PE in those who met the rule criteria was 1.4% (0.5-3.0%) and 0% (0-6.2%), respectively. The derived eight-factor block rule reduced the pretest probability below the test threshold for d-dimer in two validation populations, but the rule's utility was limited by low specificity.

Contribution of indirect computed tomography venography to computed tomography angiography of the chest for the diagnosis of thromboembolic disease in two United States emergency departments.

Recent reports suggest that physicians in non-ambulatory settings can use indirect CT venography (CTV) of the lower extremities immediately following spiral CT angiography (CTA) of the chest to identify patients with a negative CTA who have thromboembolic disease identified on CTV. We sought to determine the frequency of isolated deep venous thrombosis (DVT) discovered on CTV in emergency department (ED) patients with complaints suggestive of pulmonary embolism (PE) yet having a negative CTA. This study was conducted in a suburban and urban ED where patients with symptoms suspicious for PE were primarily evaluated with CTA and CTV. A total of 800 patients were studied, including 360 from the suburban ED and 440 from the urban ED. 88 (11%) patients were diagnosed with thromboembolic disease by CTA, or CTV, or both. Seventy-three patients had a CTA of the chest that was positive for PE, 42 (5.2%) of whom had evidence of both PE on CTA and DVT on CTV. Fifteen patients (2%, 95% CI = 1-3%) had a negative CTA and were subsequently found to have isolated DVT on CTV, all of whom received anticoagulation therapy. These data suggest that indirect CT venography of immediately following CT angiography of the chest significantly increased the frequency of diagnosed thromboembolic disease requiring anticoagulation in ED patients with suspected PE.

Triage nurse application of the Ottawa knee rule.

OBJECTIVE: To determine interobserver agreement between triage registered nurses (RNs) and emergency physicians (EPs) regarding indication for knee radiographs by applying the Ottawa knee rule (OKR) and individual components of the rule. METHODS: This was a prospective, observational study in a suburban, teaching emergency department. The study enrolled a convenience sample of patients aged >17 years with traumatic knee injuries less than one week old. Patients with prior knee surgery or distracting conditions were excluded. Before study initiation, the RNs and EPs were in-serviced in the OKR. Nurses and EPs independently examined each patient for OKR criteria, blinded to the other's assessment. Knee radiographs were ordered at the discretion of the EP and were interpreted by board-certified radiologists. All patients received follow-up with a structured telephone interview to identify any undetected fractures. Kappa was calculated for each component and the overall application of the OKR to assess interobserver agreement. RESULTS: Ninety-six patients were enrolled. The mean age was 39.6 +/- 18.7 years; 50% were male. Eight patients (8%) had knee fractures. Interobserver agreements between the RNs and EPs for individual components of the OKR were: age > or =55 years (kappa = 0.97); inability to weight bear (kappa = 0.51); inability to bend knee to 90 degrees (kappa = 0.52); fibular head tenderness (kappa = 0.45); and isolated patellar tenderness (kappa = 0.40). The EPs and RNs agreed with OKR criteria for x-ray 71% of the time (kappa = 0.41). CONCLUSIONS: The only criterion that resulted in almost perfect agreement between the RNs and EPs was patient age; agreement for the other four criteria and the overall decision to order x-rays was moderate.

Oral antibiotic use without consulting a physician: a survey of ED patients.

The purpose of our study was to determine the extent to which patients use antibiotics without consulting a physician and to examine patient characteristics associated with such oral antibiotic misuse. The study design was a prospective survey. The setting was a suburban, community, emergency department (ED). The participants were a convenience sample of oriented, ED patients who were enrolled during an 8-week period. Subjects provided written answers to standardized questions regarding their use of oral antibiotics over the 12 months preceding their ED visit. Categorical and continuous data were analyzed by chi-square and t-tests respectively. All test were 2-tailed with alpha set at 0.05. One thousand three hundred sixty three subjects were enrolled; 80% were White, 54% were female, 58% had attended college, 85% had a private physician, and 88% had health insurance. The mean age was 45 +/- 19 years. 43% of patients had used oral antibiotics within the past year. Twenty-two percent of patients indicated that their physicians routinely prescribed antibiotics for their cold symptoms. Seventeen percent of patients had taken "left-over" antibiotics without consulting their physician, most commonly for a cough (11%) or sore throat (42%), and much less frequently for urinary tract infection symptoms (0.7%). Women (19% versus 15% men; P =.04) and patients who attended college (19% versus 14% no college; P =.01) were more likely to have taken "left-over" antibiotics. A significant percentage of our ED patients had taken oral antibiotics without consulting a physician for symptoms frequently caused by viruses. Further study is warranted to examine whether local patterns of outpatient self-prescribing affect community oral antibiotic resistance.

The emergency department as a potential site for smoking cessation intervention: a randomized, controlled trial.

OBJECTIVE: To assess the effect of physician counseling and referral on smoking cessation rates and attendance at a smoking cessation program. METHODS: This was a prospective, randomized clinical trial set in a suburban, community teaching hospital emergency department (ED). During study hours, dedicated research associates enrolled consecutive, stable, oriented patients who were smokers. Eligible, consenting patients were randomized to one of two intervention groups. The control group received a two-page "Stop Smoking" pamphlet from the American Heart Association (AHA). Patients in the intervention group were given the AHA pamphlet along with pharmacologic information and standardized counseling by the attending emergency physician, including written and oral referral to a smoking cessation program. The primary outcome measures were telephone contact/attendance at the smoking cessation program by the intervention group and the rate of smoking cessation in both study groups at three months post-ED visit. Categorical data were analyzed by chi-square and Fisher's exact tests. Rank data were analyzed by Mann-Whitney tests and continuous data by t-tests. All tests were two-tailed with alpha set at 0.05. RESULTS: One hundred fifty-two patients were enrolled; 78 were randomized to the intervention group. Nearly 70% of patients (103) were available for telephone follow-up. The study groups were statistically similar with regard to baseline demographic characteristics and the prevalence of moderate or severe nicotine addiction. None of the patients (0%) in the intervention group contacted or attended the smoking cessation program during the study period (95% CI = 0-4%). The percentages of patients who stopped smoking after three months were similar in the two groups [10.4% (5/48) control vs 10.9% (6/55) intervention; p = 1]. CONCLUSION: The authors found no difference in the smoking cessation rates between ED patients who received written material and those who were counseled by emergency physicians. Referral of patients who smoked to a cessation program was unsuccessful.

Do diabetic patients have higher in-hospital complication rates when admitted from the emergency department for possible myocardial ischemia?

OBJECTIVE: To compare in-hospital complication rates for diabetic and nondiabetic patients admitted from the emergency department (ED) for possible myocardial ischemia. METHODS: This was a prospective, observational study of consecutive consenting patients presenting to a suburban university hospital ED during study hours with typical and atypical symptoms consistent with cardiac ischemia. Demographic, historical, and clinical data were recorded by trained research assistants using a standardized, closed-question, data collection instrument. Inpatient records were reviewed by trained data abstractors to ascertain hospital course and occurrence of complications. Final discharge diagnosis of acute myocardial infarction (AMI) was assigned by World Health Organization criteria. Categorical and continuous data were analyzed by chi-square and t-tests, respectively. All tests were two-tailed with alpha set at 0.05. RESULTS: There were 1,543 patients enrolled who did not have complications at initial presentation; 283 were diabetic. The rule-in rate for AMI was 13.8% for nondiabetic patients and 17.7% for diabetic patients (p = 0.09). Times to presentation were similar for nondiabetic vs diabetic patients [248 minutes (95% CI = 231 to 266) vs 235 minutes (95% CI = 202 to 269); p = 0.32]. Nondiabetic patients tended to be younger [56.6 years (95% CI = 55.8 to 57.4) vs 61.6 years (95% CI = 60.2 to 63.1); p = 0.001] and were less likely to be female (34.3% vs 48.1%; p = 0.001). The two groups had similar prevalences for initial electrocardiograms diagnostic for AMI (5.5% vs 7.4%; p = 0.21). There was no significant difference between nondiabetic and diabetic patients for the occurrence of the following complications after admission to the hospital: congestive heart failure (1.3% vs 1.1%, p = 0.77); nonsustained ventricular tachycardia (VT) (1.3% vs 1.2%, p = 0.93); sustained VT (1.2% vs 1.1%, p = 0.85); supraventricular tachycardia (1.7% vs 3.2%, p = 0.12); bradydysrhythmias (1.9% vs 1.1%, p = 0.33); hypotension necessitating the use of pressors (0.9% vs 1.1%, p = 0.76); cardiopulmonary resuscitation (0.2% vs 0.7%, p = 0.10); and death (0.3% vs 0.7%, p = 0.34). One or more complications occurred with similar frequencies for patients in the two groups (6.3% vs 5.7%; p = 0.70). CONCLUSIONS: No statistically significant difference was found in the postadmission complication rates for initially stable diabetic vs nondiabetic patients admitted for possible myocardial ischemia. Based on these results, the presence or absence of diabetes as a comorbid condition does not indicate a need to alter admitting decisions with respect to risk for inpatient complications.

Prevalence of smokers and nicotine-addicted patients in a suburban emergency department.

OBJECTIVE: To define the prevalence of smokers and nicotine-addicted patients in a suburban, community ED. METHODS: This was a prospective survey of consecutive ED patients seen in a suburban ED with an annual patient census of 48,000. Medically stable patients aged 18 years or older were eligible for inclusion. Patients were excluded if they had predominantly psychiatric complaints or were critically ill. Patients were queried about their smoking habits by a closed-question survey, which included the previously validated Fagerstrom Test for Nicotine Dependence. The study was conducted during a six-week period, only at times when there were dedicated research associates available to ensure consecutive patient entry. Continuous variables were analyzed by Student's t-tests. Clinical variables were analyzed by chi-square tests. All tests were two-tailed with alpha at 0.05. RESULTS: 1,515 patients comprised the study group. The mean age (+/-SD) was 45.6 (+/-18.9) years; 52% were female, 25% were nonwhite, and 47% were college graduates. There were 317 (21%) smokers. Patients having private physicians were less likely to smoke (18% vs 29%, p = 0.001). Of all smokers, 46% were moderately to severely nicotine-dependent, 69% wanted to quit, and 30% expressed an interest in joining a smoking cessation program. CONCLUSION: A substantial percentage of ED patients smoke, many of them are nicotine-addicted, and the majority would like to quit. Randomized, controlled trials are needed to determine whether interventions by physicians in the ED can have an impact on the smoking habits of these patients.

Droperidol for acute migraine headache.

The use of intramuscular droperidol to treat acute migraine headache has not been previously reported in the emergency medicine literature. It is a promising therapy for migraine. The authors performed a pilot review of all patients receiving droperidol for migraine in our emergency department (ED) to evaluate its efficacy. We used a retrospective case series, in a suburban ED with an annual patient census of 48,000. All patients with a discharge diagnosis of migraine headache who were treated with i.m. droperidol during a consecutive 5-month period in our ED were identified. All patients received droperidol 2.5 mg intramuscular. As per ED protocol, their clinical progress was closely followed and documented at 30 minutes after drug administration (t30). Demographic and clinical variables were recorded on a standardized, closed-question, data collection instrument. The primary outcome measurement was relief of symptoms at t30 to the point that the patient felt well enough to go home without further ED intervention (symptomatic relief). Thirty-seven patients were treated (84% female), with an ED diagnosis of acute migraine with droperidol during the study period. The mean age was 36 +/- 12 years. Analgesics had been used within 24 hours before ED presentation by 62% of patients. At t30, 30 (81%) patients had symptomatic relief, 2 (5%) felt partial relief but required rescue medication, and 5 (14%) had no relief of symptoms. Drowsiness (14%) and mild akathisia (8%) were the only adverse reactions observed following drug administration. Droperidol 2.5 mg intramuscular may be a safe and effective therapy for the ED management of acute migraine headache. Randomized, controlled trials are warranted to further validate the findings of this preliminary study.

Clinical characteristics of diabetic vs nondiabetic patients who "rule-in" for acute myocardial infarction.

OBJECTIVE: To compare the clinical characteristics of diabetic vs nondiabetic patients who present to the ED with acute myocardial infarction (AMI). METHODS: This was a prospective, observational study at a suburban, university hospital ED of patients presenting to the ED during study hours between December 1993 and October 1996 with typical and atypical symptoms consistent with cardiac ischemia. Diabetic and nondiabetic patients with AMI were compared. Demographic, historical, and clinical data were recorded by trained research assistants using a standardized, closed-question, data collection instrument. Final discharge diagnosis of AMI was assigned by WHO criteria. Continuous variables were analyzed by t-tests. Clinical variables were analyzed by chi-square tests. All tests were two-tailed with alpha preset at 0.05. RESULTS: There were 216 patients with AMI during the study period; 51 of these patients (24%) were diabetic. For diabetic vs nondiabetic patients with AMI, there was no significant difference in age (64.0 +/- 13 vs 60.0 +/- 14 years, p = 0.13), female gender (37% vs 26%, p = 0.13), and time to presentation from symptom onset (192 +/- 238 vs 251 +/- 456 minutes, p = 0.41). Hypertension was the only cardiac risk factor significantly more prevalent in diabetic vs nondiabetic patients with AMI (77% vs 50%, OR = 1.54, 95% CI = 1.24 to 1.91, p = 0.001), though elevated cholesterol (48% vs 33%, OR = 1.47, 95% CI = 1.02 to 2.12, p = 0.06) tended to be more prevalent in the diabetic group. There was no statistically significant difference between the two groups in terms of the frequency of chest pain (OR = 1.04, 95% CI = 0.95 to 1.14, p = 0.30), associated symptoms, and diagnostic ECGs (OR = 1.16, 95% CI = 0.76 to 1.79, p = 0.53). CONCLUSION: Diabetic patients with AMI may have similar symptoms upon presentation as do nondiabetic patients with AMI. Of the cardiac risk factors, hypertension is more prevalent in diabetic vs nondiabetic patients with AMI.

The effectiveness of ice as a topical anesthetic for the insertion of intravenous catheters.

In a paired clinical trial, the effectiveness of ice in reducing the pain of intravenous catheter placement was assessed in 28 adult volunteers. An ice pack was placed over one arm for 10 minutes, followed by insertion of an 18-gauge angiocatheter in both arms. Patients recorded their pain assessment after each venipuncture on a previously validated 100-mm visual analog scale (VAS) and identified their preferred method for the procedure (pretreatment with ice or no pretreatment). The mean pain score for catheter placement on arms pretreated with ice was 27.5+/-15.9 mm; the mean pain score for the control arms was 34.2+/-21.6 mm (P = .17). Most patients (61%) preferred no pretreatment (P = .014). Although most men (75%) preferred no pretreatment, 75% of women preferred pretreatment with ice (P = .014). Future studies should examine whether ice is effective at reducing pain from other more painful procedures and whether the response to ice is gender-related.

The etiology of cardiac arrest in children and young adults: special considerations for ED management.

Children and young adults rarely present to the emergency department (ED) in cardiac arrest. This review examines published series on nontraumatic, cardiac arrest for patients aged 1 to 45 years and discusses the differential diagnosis for cardiovascular collapse. Among the most common entities encountered are cardiac diseases (hypertrophic cardiomyopathy, myocarditis), airway diseases (pneumonia, epiglottitis, and asthma), epilepsy, hemorrhage (gastrointestinal bleeding, ectopic pregnancy), and drug toxicity (tricyclic antidepressants, cocaine). ED management of children and young adults in cardiac arrest requires an understanding of the heterogeneous pathophysiologic mechanisms and etiologies leading to cardiopulmonary dysfunction in these patients. The emergency physician should give particular focus to airway management for toddlers and preadolescents, because respiratory diseases predominate. When treating an adolescent or young adult, the resuscitation team should also consider toxic causes as well as occult hemorrhage. Management considerations unique to this patient population are discussed.

Comparison of patient and practitioner assessments of pain from commonly performed emergency department procedures.

STUDY OBJECTIVE: To compare patient and practitioner assessments of pain associated with commonly performed emergency department procedures and use of anesthetics before these procedures. METHODS: This was a prospective, observational, cross-sectional study conducted at a university-based ED with a convenience sample of ED patients. Research assistants recorded the procedure performed and historical and demographic information on standardized data collection instruments. After each procedure, both the patient and practitioner independently recorded assessments of patient pain on a 100-mm visual analog scale (VAS). Use of preprocedure anesthetics and patient preferences regarding their use were also identified. Categorical variables were analyzed by chi(2) tests. Patient and practitioner VAS scores were compared using a paired t test; alpha was preset at .05. Correlation coefficients were calculated to assess correlation between patient and practitioner pain scores. RESULTS: A total of 1,171 procedures were evaluated for the 15 most common procedures performed. The mean patient age was 42.8+/-18.7 years and 46.1% were male. Overall, the mean patient VAS was 20.8 mm+/-25.1 mm; the mean practitioner VAS was 23.5 mm+/-20.3 mm. The mean difference between groups was 3.0 mm (95% confidence interval [CI], 1.3 to 4.1). Correlation between patient and practitioner pain scores for individual procedures was poor to fair (r=.26 to.68). The most painful procedures according to patients in descending order were nasogastric intubation, abscess drainage, fracture reduction, and urethral catheterization. Local anesthetics were administered in 12.8% of procedures yet would be requested before similar future procedures by 17.1% of patients. Patients who would choose local anesthetics in the future gave higher pain scores than those who would not (43.3 mm versus 16.3 mm; mean difference=27.0 mm, 95% CI, 22.2 to 31.8 mm). CONCLUSION: The most painful procedures for ED patients were nasogastric intubation, incision and drainage of abscesses, fracture reduction, and urethral catheterization. Although practitioners also identified these procedures as most painful, the correlation between patient and practitioner pain assessments in individual patients was highly variable. Overall use of anesthetics before these procedures was low. Practitioners should be attentive to their patients' individual anesthetic needs before performing painful procedures.

Irrigation in facial and scalp lacerations: does it alter outcome?

STUDY OBJECTIVE: Animal and human studies suggest that irrigation lowers the infection rate in contaminated wounds, but there is no evidence that this common practice is beneficial for "clean" lacerations. We tested the null hypothesis that there is no difference in the infection rate for noncontaminated lacerations to the face and scalp that are irrigated before primary closure compared with similar wounds that are closed primarily without irrigation. METHODS: We performed a cross-sectional study of consecutive patients presenting to a suburban, academic emergency department between October 1992 and August 1996. Patients with nonbite, noncontaminated facial skin or scalp lacerations who presented less than 6 hours after injury were included. Structured, closed-question data collection instruments were completed at the time of laceration repair and at suture removal. The primary outcome parameters were the incidence of wound infection and the short-term cosmetic appearance of lacerations in patients who did or did not receive irrigation. RESULTS: A total of 1,923 patients were included in the study group; 1,090 patients received saline irrigation, and 833 patients did not. The irrigation and nonirrigation groups were similar with regard to time from injury to presentation (1.56 versus 1.42 hours, respectively), frequency of linear wound morphology (82% versus 88%), frequency of smooth wound margins (72% versus 82%), number of layers of closure (1.14 versus 1.26), number of skin sutures applied (4.98 versus 4.65), number of deep sutures applied (.70 versus 1.05), and use of oral antibiotic prophylaxis (2.8% versus 4.0%). With respect to outcomes, the incidence of wound infection was not significantly different between the two treatment groups (.9% versus 1.4%, respectively; P = .28). Likewise, the percentage of patients who had an "optimal" cosmetic appearance was similar in the two groups (75.9% versus 81.7%, respectively; P = .07). CONCLUSION: Irrigation before primary closure did not significantly alter the rate of infection or the cosmetic appearance in our study population with clean, noncontaminated facial and scalp lacerations.

Performance of two clinical decision rules for knee radiography.

We designed a prospective observational study to attempt to validate two recently described clinical decision rules for knee radiography. Consecutive patients aged > or = 15 yr with acute knee injuries occurring less than 1 wk prior to presentation were included for study. Patients with distracting conditions, open knee injuries, or previous surgery were excluded. Each patient was assessed for 7 historical and 15 physical examination criteria that were recorded on a standardized data collection instrument. Radiographs were ordered at the discretion of the attending physician and were read by two board-certified radiologists. When radiographs were not ordered, structured telephone follow-up was performed after 3 wk. The main outcome parameter was the presence or absence of a clinically significant fracture. There were 351 patients in the study; 26 (7%) had knee fractures. Fractures were significantly associated with an increased prevalence for two of the three criteria in the rule derived by Bauer: inability to weight bear immediately or in the emergency department (ED; 76.9% of patients with a fracture vs. 29.8% of patients without a fracture) and effusion (53.8% vs. 28.9%, respectively). Ecchymosis was not significantly associated with fracture (19.2% with fracture vs. 9% with no fracture). Use of the Bauer rule would have led to a radiographic evaluation of 22 of the 26 patients with knee fractures (sensitivity = 84.6%, specificity = 48.9%). Fractures were associated with a significantly increased prevalence for three of the five criteria in the decision rule proposed by Stiell: isolated patella tenderness (30.8% with fracture vs. 14.5% with no fracture), inability to flex the knee to 90 degrees (42.3% vs. 19.7%, respectively), and inability to weight bear immediately and in the ED (57.7% vs. 18.8%, respectively). Age > or = 55 yr (23.1% vs. 12.0%, respectively) and fibula head tenderness (11.5% vs. 5.5%, respectively) were not significantly associated with fracture. Use of the Stiell rule would have led to radiographic evaluation of 22 of the 26 patients with knee fractures (sensitivity = 84.6%, specificity = 49.8%). We conclude that neither clinical decision rule is 100% sensitive. Further refinement will be necessary to identify all patients with knee fractures.