Selective use of single-photon emission computed tomography myocardial perfusion imaging in a chest pain center.

Emergency department chest pain centers (CPCs) vary in their approach to patients with chest pain and nonischemic electrocardiograms (ECG). Although single-photon emission computed tomography (SPECT) myocardial perfusion imaging has been evaluated in this setting, both acutely at rest and after stress, we questioned its application in all patients. We prospectively evaluated the utility of selective SPECT imaging in a CPC (i.e., rest SPECT for ongoing pain, stress SPECT if unable to undergo exercise electrocardiography) and its impact on the overall disposition of all emergency department chest pain patients. Over 3 years, 2,601 patients were evaluated in a CPC (2,211 [85%] were sent home, 390 [15%] were hospitalized). Of 390 CPC patients hospitalized, 182 (47%) were diagnosed with coronary artery disease at the time of hospital discharge. Only 28 patients (1.1%) had an acute myocardial infarction. After 3 years, the proportion of all chest pain patients hospitalized and those diagnosed as "rule-out myocardial infarction" decreased from 53% to 41% and 32% to 18% of all chest pain patients, respectively (both p <0.0001). Overall, 906 patients (35%) required SPECT imaging to complete the CPC evaluation. Had SPECT imaging not been performed selectively, and all 906 patients been admitted, 762 (29%) would have been hospitalized unnecessarily based on the final diagnoses. Alternatively, sending all these patients home would have resulted in 144 (6%) inappropriate discharges of patients with coronary artery disease. A CPC protocol using the selective use of SPECT imaging permits the complete evaluation of all patients in the CPC, significantly reduces hospitalizations for chest pain, and restricts hospital admission to more appropriate patients.

Care and outcome of out-of-hospital deliveries.

OBJECTIVES: To identify interventions by paramedics in out-of-hospital deliveries and predictors of neonatal outcome. METHODS: A prospective case series of consecutive out-of-hospital deliveries at Yale-New Haven Hospital from January 1991 to January 1994. Data describing out-of-hospital interventions, demographics, maternal risk factors, and neonatal outcomes were collected from out-of-hospital, emergency department (ED), and hospital records. Subgroups defined by source of prenatal care were compared using a multiple-logistic regression model to determine predictors of poor neonatal outcome. RESULTS: Ninety-one patients presented to the hospital after delivery. Paramedics attended 78 (86%) of the cases. Paramedics performed endotracheal intubation in one neonate and supported ventilation in four others. Suctioning and warming of the neonate were documented in 58% and 76%, respectively, and hypothermia was common (47%) in the paramedic-attended deliveries. There were 9 neonatal deaths. Eight (89%) of the neonatal deaths were in the group with no prenatal care (p < 0.0001). Lack of prenatal care (RR 304, 95% CI = 5.0 to 18,472) and history of poor prenatal care (RR 22.5, 95% CI = 1.19 to 427) were significant predictors of poor neonatal outcome. Sixteen percent of all study patients and 43% of those with no prenatal care were treated in the ED during their pregnancies. Eighteen percent of the patients had had no prenatal care during previous pregnancies. CONCLUSIONS: Paramedics manage labor and delivery of a high-risk population. Fundamental aspects of care were not universally documented. Lack of prenatal care was associated with high neonatal morbidity and mortality. Nearly half of the mothers who went on to deliver without prenatal obstetric care saw emergency physicians during their pregnancies.

Pattern-Based Interactive Diagnosis of Multiple Disorders: The MEDAS System.

A knowledge-based interactive sequential diagnostic system is introduced which provides for diagnosis of multiple disorders in several body systems. The knowledge base consists of disorder patterns in a hierarchical structure that constitute the background medical information required for diagnosis in the domain under consideration (emergency and critical care medicine, in our case). Utilizing this knowledge base, the diagnostic process is driven by a multimembership classification algorithm for diagnostic assessment as well as for information acquisition [1]. A key characteristic of the system is congenial man-machine interface which comes to expression in, for instance, the flexibility it offers to the user in controlling its operation. At any stage of the diagnostic process the user may decide on an operation strategy that varies from full user control, through mixed initiative to full system control. Likewise, the system is capable of explaining to the user the reasoning process for its decisions. The model is independent of the knowledge base, thereby permitting continuous update of the knowledge base, as well as expansions to include disorders from other disciplines. The information structure lends itself to compact storage and provides for efflcient computation. Presently, the system contains 53 high-level disorders which are diagnosed by means of 587 medical findings.

A survey of prehospital care paramedic/physician communication for Multnomah County (Portland), Oregon.

All field paramedic/patient encounters requiring advanced life support management in Multnomah County, Oregon, required radio/telephone communications with the emergency department physicians of the county's single medical resource hospital for a period of 6 months. A survey of these communications (compliance estimated to be 75% to 80%) demonstrated that paramedics established contact during management or transport in one-half of instances and after transport in the remainder. Consultation was estimated to be helpful in 12% to 17% of cases and of critical importance rarely. Additional benefits were seen in hospital notification, education, and as an adjunct to the medical record; and the concept of a single centralized resource hospital was established in this community.

Multicenter HIV and hepatitis B seroprevalence study.

Prior single institutional investigations have found unrecognized HIV seroprevalence in emergency department (ED) patients to range from 0.38% to 4%. A prospective, anonymous study of HIV and hepatitis B (HB) seroprevalence was performed on excess serum of all ED patients over two 48-hour periods in May and August, 1988, from 7 hospitals in the Portland metropolitan area. Demographics were known for 338/444 (76%) of patients. Forty-six percent were male, 85% white, with a median age group of 30-39 years. Ambulance transport, trauma, external blood, presentations requiring ED procedure(s), and acuity resulting in ICU admission were present on 21%, 7%, 10%, 34%, and 14% of patients, respectively. Two of 444 (.45%) patients were HIV +, one previously undiagnosed. Fifty-five of the 444 (12%) and 3 of 444 (0.6%) samples were positive for HBcAB and HBsAG respectively. Risk factor assessment was possible on 180/444 (40%) patients. HBcAB seroprevalence correlated with race (P less than 0.01), IV drug use (P less than 0.0001), and hospital location, (P less than 0.006) but were sensitive in detecting only 14%, 18%, and 38%, respectively, of HBcAB+ patients. HBcAB was not associated with the following factors: sex, area of residence, presence of blood externally, trauma, acuity of illness, ED procedures, or mode of transport. This data strongly support the use of universal body fluid precautions. Hepatitis B poses a significant and distinct risk to all emergency care providers. HB vaccination should be strongly advocated for all ED health care workers (HCWs). Emergency medicine multicenter studies are both desirable and feasible.

Computerized hospital on-line resources allocation link (CHORAL): a mechanism to monitor and establish policy for hospital ambulance diversions.

Ongoing monitoring of the availability of hospital critical care resources is necessary to assure patients in the emergency medical services (EMS) system reach appropriate care. In this densely populated area Multnomah County, Oregon, ambulances have been diverted by radio from several hospitals before finding one that would accept the patient. Dispatch centers and base-stations had no reliable method to monitor the availability of hospital resources. Data were not available for use in establishing policy. In response, this community developed an on-line, computerized system known as Computerized Hospital On-Line Resources Allocation Link (CHORAL) that visually displays the resource status of all hospitals to the 911 center, base station, and participating hospitals. A change of status requires simple keystrokes for entry into the computer which in turn transmitted automatically to all other CHORAL computers. Six patient care resources are monitored: Adult Ward (AW); Computerized Axial Tomography Scan (CT); Critical Care (CC); Labor and Delivery (LD); Pediatric (PEDS); and Psychiatric Secure Beds (PSB). Paramedics use protocol to determine if a particular patient fits one of these categories. Availability is relayed to paramedics by the 911 center and the base-station. During the first three months of system operation, there were 337 diversions representing 4,527 hours among 10 of the 12 participating hospitals. The most common resource resulting in diversion was PSB, which was unavailable for 2,195 hours (48.5%). Unavailability of CT resulted in the lowest number of diversions (1.3%, 60.3 hours).(ABSTRACT TRUNCATED AT 250 WORDS)