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.

Ultrasound-guided Kopans' needle location and removal of a retained foreign body.

Penetrating injury with retained foreign body is a common problem. Location of the foreign body and surgical excision may be difficult. Ultrasound can be a sensitive and cost-effective tool in both the detection and surgical removal of retained foreign bodies in soft tissue. We report a case in which ultrasound-guided needle localization was used for removal of a wooden foreign body

Biliary dyskinesia: a study of more than 200 patients and review of the literature.

The diagnosis and treatment of biliary dyskinesia, defined as symptoms of biliary colic in the absence of gallstones, remains controversial and has been the subject of several previous retrospective reviews. The diagnosis and treatment of biliary dyskinesia based on the CCK-HIDA scan, and the outcome with cholecystectomy for billary dyskinesia, are reviewed. We add more than 200 cases of cholecystectomy for biliary dyskinesia, and compare our results with those of previous reports. We retrospectively reviewed 295 patients with biliary dyskinesia who underwent cholecystectomy at three military hospitals between 1988 and 1995. All patients had symptoms consistent with biliary colic and preoperative evaluations that revealed no evidence of cholelithiasis. Pathology specimens were reviewed for cholelithiasis and pathologic changes. Data were retrieved by chart review and clinic evaluation of new patients. Individual follow-up of each patient was attempted. Follow-up was achieved in 218 of the 295 patients for a rate of 74%. The mean duration of follow-up was 506 days with a range of 22 days to 6 years. Two hundred patients (92%) had CCK-HIDA scans with an ejection fraction (EF) >=<50%. Eighteen patients (8%) had an EF >50% but did have reproduction of their symptoms with CCK injection. In the group with an EF <50%, 94.5% were improved or cured with cholecystectomy. In the group with an EF >50% and pain reproduction, the improved or cured rate was 83.4%. CCK-HIDA scans are useful for diagnosing biliary dyskinesia and predicting improvement after cholecystectomy. Patients presenting with biliary dyskinesia and an EF <50% on CCK-HIDA scan have 94% improvement or resolution of their symptoms after cholecystectorny. CCK-HIDA scans should be employed early in the evaluation of billary colic with no evidence of cholelithiasis (i.e., with a normal ultrasound scan). When test results are abnormal, cholecystectomy should be performed, since the results in this setting approach those of cholecystectomy for stone disease (>90% cured/improved). In the current climate of cost containment, these excellent results would obviate the need for extensive and expensive medical testing before surgical therapy is recommended.

Emergency department patients with assault injuries: previous injury and assault convictions.

STUDY OBJECTIVE: To compare the incidence of previous assault injury and assault conviction of patients presenting to the ED with assault injuries and the incidence of assault injury and conviction in nonassaulted control patients. METHODS: We conducted a retrospective, medical record-based case-control study of ED patients with assault injuries and matched controls presenting with medical and surgical problems unrelated to assault. The setting was the ED of a 900-bed teaching hospital and Level I trauma center in an urban area. Our subjects were 50 patients who presented as victims of blunt trauma, 50 patients who presented with penetrating trauma, and 100 control subjects matched by age, sex, and ZIP code who presented concurrently with nonassault complaints. RESULTS: The overall rate of previous assault injury was 35% and did not differ between cases and controls. Fifty-three patients had a history of criminal conviction, and 23 had a history of conviction for assault. Fewer patients presenting with assault injuries than controls had a history of conviction for assault (odds ratio [OR], .3; P < .02). Patients with penetrating injuries had the lowest incidence of assault conviction (OR, .13; P < .02). The subgroup of case subjects with criminal records had a higher rate of previous injury than those without records (P < .003). CONCLUSION: ED patients with assault injuries did not have a history of assault injuries exceeding that of controls and were less likely to have been convicted of assault. Violence-prevention programs should be directed toward a broader population of ED patients instead of narrowly focusing on victims of assault.

Paramedic field instructors: an approach to training the newest paramedics while maintaining the interest of the most successful senior paramedics.

A unique approach to providing orientation and supervised field experience for newly graduated paramedics and for the continuing education and recognition of experienced, skilled, operational paramedics is described. A group of 30 paramedic field instructors (PFI) was selected following application, development of criteria for selection, and interviews. This program had a positive effect in both realms during its first year of operation in the emergency medical services system in which it was implemented.

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)

The effect of base station contact on ambulance destination.

Concern has been raised that a single medical control base station serving a metropolitan area may preferentially divert ambulance patients to the base station hospital. Such concern may discourage the development of regional medical control systems. During the first six months of 1988, a retrospective cross-sectional analysis was made of all advanced life support (ALS) ambulance transports and all contacts to the single base station, known as Medical Resource Hospital (MRH). Destinations of all ALS ambulance calls dispatched through the county's 911 dispatch center were analyzed to determine whether the destinations were affected by MRH contact. There were 12,396 transports to 17 area hospitals with 1,272 (10.3%) of these requiring MRH contact. We hypothesized that if MRH contact did not affect destination, the proportion of all non-MRH ALS ambulance patients received by each hospital from the 911-dispatched group would equal the proportion of patients received by each hospital after MRH contact. Five hospitals received a statistically significant (P less than .003) different percentage of MRH contact patients than their proportion of 911-dispatched patients would have predicted. The three that received more were community hospitals in outlying areas. The remaining two were a large referral hospital and a smaller community hospital located in the urban area. The MRH hospital did not have a significantly different percentage of 911-dispatched patients after MRH contact. Similarly, destinations of specific ALS ambulances (two serving in the MRH ambulance catchment area and four in distant catchment areas) were evaluated.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

Immigration issues in hiring alien physicians as teachers.

Although U.S. immigration laws give favorable treatment to college and university teachers, hiring of alien physicians by medical schools and health sciences universities remains problematic, reflecting the impact of the 1976 Health Care Professions Act and the Immigration Control and Reform Act of 1986. The authors outline the steps in the hiring process to provide a useful reference for department chairpersons and division heads and to help them deal with the school administrators, attorneys, and immigration officials they will encounter during the hiring process. Of particular importance is understanding recruiting procedures, visa classifications, and the prohibition in hiring physicians directly from their U.S. residency and fellowship positions without having them first return for two years to their home countries. A common error is to recruit medical school faculty without first considering that the final candidates might be aliens; when they are, the process of hiring aliens must be dealt with retroactively. Immigration law currently does allow hiring an alien physician (as a teacher) if that physician is the most qualified candidate.

The effect of on-line medical control centralization on ambulance destination.

Controversy regarding the establishment of on-line medical control in a single hospital in a regional Emergency Medical Service System is based, in part, upon the suspicion that ambulances might be diverted to that hospital. Ambulance transports to the University Hospital of Portland, Oregon, were studied over a six year period coinciding with that facilities' assumption of on-line medical control functions. No increases in ambulance transports to that facility could be demonstrated. Other variables resulted in absolute decreases in the number of these transports.

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.

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.