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R A Swor

Publications and source records attributed to R A Swor.

35 records · Page 2Linked to original sources

Characteristics of fatal ambulance crashes during emergency and non-emergency operation.

OBJECTIVE: To analyze the characteristics of fatal ambulance crashes to assist emergency medical services (EMS) directors in objectively developing their EMS system's policy governing ambulance operations. HYPOTHESIS: No difference exists between the characteristics of fatal ambulance crashes during emergency and nonemergency use. DESIGN: Retrospective, cross-sectional, comparative analysis of ambulance crashes resulting in fatalities reported to the Fatal Accident Reporting System (FARS) from 1987 to 1990. METHODS: Twenty variables, representing characteristics of fatal ambulance crashes, were selected from the National Highway Traffic Administration FARS Codebook and were evaluated using tests of significance for categorical data grouped by emergency use and nonemergency use. Crash variable categories examined included demographics, accident configuration, accident severity, vehicle description, and ambulance operator action. RESULTS: During the four-year study period, 109 fatal ambulance crashes occurred producing 126 deaths. Four states, New York, Michigan, California, and North Carolina, accounted for 37.5% of all fatal crashes. Seventy-five fatal crashes (69%) occurred during emergency use (EU) and 34 fatal crashes (31%) occurred during nonemergency use (NEU). The total number of fatal crashes varied in a downward trend (1987:32; 1988:24; 1989:28; 1990:25). The number of fatal EU crashes also varied in a downward trend (1987:28; 1988:16; 1989:19; 1990:12), while the number of fatal NEU crashes increased each year [1987:4; 1988:8; 1989:9; 1990:13](p = .016). Most EU fatal crashes occurred between 1200 h and 1800 h (p = .009). Most NEU fatal crashes occurred during times when light conditions were poor (p = .003). When a violation was charged to the ambulance driver (17 cited), the vehicle was more likely to be in EU (p = .056). No statistically significant differences between EU and NEU were identified by: 1) day of week; 2) season; 3) atmospheric conditions; 4) roadway surface type; 5) roadway surface condition; 6) speed limit; 7) roadway alignment; 8) relationship to junction; 9) manner of collision; 10) year manufactured; 11) vehicle role; 12) vehicle maneuver; 13) manner leaving scene; 14) extent of deformation; 15) violations charged; or 16) number of persons killed in accident. CONCLUSION: Few characteristics differentiate between fatal ambulance crashes during EU and NEU. The difference between EU and NEU were statistically significant in only three out of the 20 variables examined: 1) year occurred; 2) time of day; and 3) light condition. These data provide few objective measures that may be used to develop ambulance operation policies to decrease fatal ambulance crashes.

Accidents, Traffic↗

Impact of lay responder actions on out-of-hospital cardiac arrest outcome.

INTRODUCTION: Little peer-reviewed literature exists regarding the actions of the person who recognized and called 911 at the time of an out-of-hospital cardiac arrest (OHCA). OBJECTIVES: To describe the characteristics of persons who recognized OHCAs and to assess the impact of their actions on survival. METHODS: Subjects were a convenience sample of individuals who called 911 after a case of home OHCA in which the victim was transported to one of two suburban community teaching hospitals. A retrospective mail survey was conducted asking demographics, including age, race, educational level, prior first aid training, and actions upon recognition of OHCA, including phone calls made and caller estimate from collapse to 911 call. Callers whose initial action was calling 911 were compared with those who made other calls first. Outcomes (discharged alive, DC) were obtained from hospital records. Fisher's exact test and chi-square tests were used for analysis. RESULTS: Of 378 cases, 173 (45.8%) responded to the mail survey. The lay responders (LRs) who called 911 were younger than the victims (59.9 vs 68.0, p < 0.001) and were most commonly spouses (65.3%) or adult children (22.0%) of the patient. Most (84.7%) called 911 first at the time of recognition of arrest. A first call to 911 tended to predict DC (11.0% vs 0.0%, p = 0.13). When a phone call other than 911 was made first, there were no survivors (0/23). An estimated delay to 911 call of >4 minutes was not associated with an adverse outcome (10.5% vs 6.9%, p = 0.49). There was no difference in demographic variables between immediate and delayed 911 callers. CONCLUSION: Lay responder demographics are similar to those of patients. In this study, an LR call to 911 first appears to be associated with improved OHCA survival. The LR estimates of delay to 911 call were not associated with increased mortality. The authors identified no patient or witness characteristics that were associated with a delay to calling 911 first.

Adult↗

Acute coronary syndrome: pharmacotherapy.

Acute coronary syndrome (ACS) refers to the spectrum of cardiac disease, from unstable angina to ST-segment-elevation myocardial infarction. In the emergency medical services (EMS) setting, ACS may be more broadly thought to include patients with chest pain or other symptoms believed to have a cardiac origin who have evidence of ischemia or acute myocardial infarction on a 12-lead electrocardiogram, or symptomatic patients with a previous cardiac event or known cardiac disease. Pharmacologic management of these patients is based on the use of three primary classes of drugs: those that affect clotting, those that establish and maintain hemodynamic control, and those that relieve pain. Many of these agents have been evaluated in large clinical trials for in-hospital use, and a number of ongoing studies are assessing their efficacy in the prehospital setting. The appropriateness of prehospital use of specific agents within each class depends on proper patient selection, the necessity of immediate intervention, ease of use in the field, expertise of EMS personnel, and cost-effectiveness of therapy. This consensus group reviewed agents from all three classes (including aspirin, GPIIb/IIIa inhibitors, unfractionated and low-molecular-weight heparins, fibrinolytics, beta-adrenergic blockers, calcium antagonists, nitrates, and morphine) for their overall indication, applicability to the prehospital setting, and current prehospital use.

Acute Disease↗

Optimal prehospital cardiovascular care.

Optimal prehospital cardiovascular care may improve the morbidity and mortality associated with acute myocardial infarctions (AMIs) that begin in the community. Reducing the time delays from AMI symptom onset to intervention begins with maximizing effective patient education to reduce patient delay in recognizing symptoms and seeking assistance. Transportation delays can be minimized by appropriate use of 911 systems and improving technological 911 support. Patient triage to heart centers from the prehospital setting requires strict and comprehensive definition of the criteria for these centers by competent, unbiased clinical societies or governmental agencies. Prehospital 12-lead electrocardiograms and initiation of thrombolytic therapy can provide acute diagnosis and early treatment, thus facilitating faster processing and more directed in-hospital intervention. They also minimize over- and undertriage of patients to cardiac centers. Although evidence from investigational trials suggests that many of these procedures are effective, more research is required to ensure correct implementation and quality assurance at all emergency service levels.

Chest Pain↗

Concepts and application of prehospital ventilation.

Airway management and optimal ventilation are crucial aspects of managing out-of-hospital medical emergencies. The goals in these situations are controlled ventilation and optimized inspiratory time, expiratory time, and airflow. Numerous techniques and devices are available to deliver oxygen-enriched air to patients during resuscitation. The bag-valve-mask (BVM) is one of the most common devices used to provide ventilation, although the American Heart Association ranks BVM devices lower in preference than other ventilation adjuncts, such as emergency and transport ventilators (ETVs) and pocket masks. The clearly documented limitations of BVM ventilation and its widespread use in the United States underscore the need to improve ventilation practices during care provided by emergency medical services (EMS) personnel. As part of that improvement, ETVs clearly have a role in the prehospital setting. These devices should be available on every ambulance, and the ability to use ETVs should be part of each EMS provider's skill set. Furthermore, all patients requiring emergency ventilation must be adequately monitored, including continuous monitoring of end-tidal carbon dioxide concentrations. As with any other skill, ventilation requires attention during initial training, continuing education and skill reinforcement, and quality review.

Carbon Dioxide↗

Resuscitation in the out-of-hospital setting: medical futility criteria for on-scene pronouncement of death.

The complete and irreversible cessation of life is often difficult to determine with complete confidence in the dynamic environment of out-of-hospital emergency care. As a result, resuscitation efforts often are initiated and maintained by emergency medical services (EMS) providers in many hopeless situations. Medical guidelines are reviewed here to aid EMS organizations with respect to decisions about: 1) initiating or waiving resuscitation efforts; 2) the appropriate duration of resuscitation efforts; and 3) recommended procedures for on-scene or prehospital pronouncement of death (termination of resuscitation). In cases of nontraumatic cardiac arrest, few unassailable criteria, other than certain physical signs of irreversible tissue deterioration, exist for determining medical futility at the initial encounter with the patient. Thus, the general medical recommendation is to attempt to resuscitate all patients, adult or child, in the absence of rigor mortis or dependent lividity. Conversely, wellfounded guidelines now are available for decisions regarding termination of resuscitation in such patients once they have received a trial of advanced cardiac life support. In practice, however, the final decision to proceed with on-scene pronouncement of death for these patients may be determined more by family and provider comfort levels and the specific on-scene environment. For patients with posttraumatic circulatory arrest, the type of injury (blunt or penetrating), the presence of vital signs, and the electrocardiographic findings are used to determine the futility of initiating or continuing resuscitation efforts. In general, patients who are asystolic on-scene are candidates for on-scene pronouncement, regardless of mechanism. With a few exceptions, blunt trauma patients with a clearly associated mechanism of lethal injury are generally candidates for immediate cessation of efforts once they lose their pulses and respirations. Regardless of the medical futility criteria, specialized training of EMS providers and targeted related testing of operational issues need to precede field implementation of on-scene pronouncement policies. Such policies also must be modified and adapted for local issues and resources. In addition, although the current determinations of medical futility, as delineated here, are important to establish for societal needs, the individual patient's right to live must be kept in mind always as new medical advances are developed.

Adolescent↗

Spinal immobilization in the field: clinical clearance criteria and implementation.

Awareness of the health and financial repercussions of unnecessary immobilization has made cervical spinal immobilization controversial in out-of-hospital care. Clinical criteria for clearance of the cervical spine in the hospital based on mechanism of injury have been supported by many trauma centers. However, implementation of clinical criteria for cervical spinal clearance in out-of-hospital settings is not as well validated by multicenter studies or accepted by many emergency departments. This consensus group recommends that clinical criteria to determine "low-risk" patients be available for use by emergency medical services providers in out-of-hospital settings; however, training, audits, quality management, integration into the medical community, and extent of program implementation should be decided based on individual emergency medical services systems.

Age Factors↗

Prehospital clinical findings associated with spinal injury.

OBJECTIVE: The objective of this study was to identify clinical findings that are associated with spinal fracture and/or spinal cord injuries in prehospital trauma patients. METHODS: A retrospective chart review was performed at three tertiary referral centers in Southeastern Michigan. All charts of patients with spinal fractures or spinal cord injuries during 1992 and 1993 were reviewed. Patients with available prehospital records were included in the study analysis. Prehospital data points included documentation of head injury; altered mental status; neurologic deficit; evidence of intoxication; cervical, thoracic, and lumbar pain or tenderness; nonspecified back pain or tenderness; and a narrative for all other documented injuries. Hospital data collected included type and level of spinal injury and age and sex of the patient. RESULTS: Of 867 injury patients identified, 536 were excluded, leaving 346 analyzable fractures in 331 patients. The 346 spinal fractures/spinal cord injuries were distributed as: 100 (29%) cervical, 83 (24%) thoracic, 128 (37%) lumbar, and 35 (10%) sacral. Prehospital documentation of altered mental status, neurologic deficit, evidence of intoxication, spinal pain, or suspected extremity fracture was found for every patient with a cervical injury, 82/83 patients with thoracic injuries (99%), and 124/128 patients with lumbar injuries (97%). All five patients who were not documented as having one of the predictors had stable injuries. CONCLUSION: Prehospital clinical findings of altered mental status, neurologic deficit, evidence of intoxication, spinal pain, and suspected extremity fracture were documented for all patients with significant spinal injuries in this series. These findings may be useful to identify patients who require prehospital spinal immobilization.

Adult↗

Outcomes of cardiac arrest in the nursing home: destiny or futility? [see comment].

OBJECTIVE: To compare EMS system characteristics and outcomes between nursing home (NH) patients and out-of-hospital cardiac arrest (OHCA) patients whose arrests occurred in a residence (home). DESIGN: Prospective cohort study reviewing OHCA from July 1989 to December 1993. Variables were age, witnessed arrest, response intervals, automated external defibrillator (AED) use, and arrest rhythms. Outcomes were hospital admission and discharge. Pearson chi-square was used for analysis. SETTING: Suburban EMS system. SUBJECTS: Patients > or = 19 years old with arrest of presumed cardiac cause, with locations at home or at a NH. RESULTS: 2,348 total arrests were complete for analysis, 182 at a NH and 2,166 at home. BLS and ALS response intervals were shorter for the NH patients. The NH patients were more likely to receive CPR on collapse, were older (73.1 vs 67.5 years, p < 0.001), were less likely to have had an AED used (9.9% vs 30.0%, p < 0.001), and were more likely to have an arrest bradyasystolic rhythm (74.7% vs 51.5%, p < 0.001). They were less likely to survive to hospital admission (10.4% vs 18.5%, p < 0.006) and discharge (0.0% vs 5.6%, p < 0.001). CONCLUSION: During this four-and-a-half-year study period, no NH patient survived, even though % CPR was increased. Arrest rhythm is an important factor in this finding. EMS initial care for ventricular tachycardia/fibrillation NH patients, with less application of AEDs, was identified. This different response may adversely contribute to dismal NH outcome.

Adult↗

Derivation and validation of criteria for determining the appropriateness of nonemergency ambulance transports.

OBJECTIVE: Nonemergency ambulance transports (NETs) represent a substantial proportion of all ambulance transports. Recently, the medical necessity of a substantial number of NETs has been questioned. The purpose of the study was threefold: 1) to formulate criteria for NET using a multidisciplinary panel; 2) to develop a structured implicit review instrument (SIRI) for the evaluation of NET from the criteria formulated; and 3) to evaluate the reliability and validity of the SIRI. Previously, a validated instrument has not been available to assess NET appropriateness. METHODS: Using a modified Delphi process and scale development techniques, a panel of ten multidisciplinary health care professionals determined criteria for NET and developed a SIRI consisting of two dimensions: 1) ambulation status and 2) medical care requirements. A convenience sample of 50 cases (occurring January through May 1996) were retrospectively reviewed by individual panel members and two panels, and categorized as either: 1) definitely appropriate NET; 2) possibly appropriate NET; 3) patient did not require ambulance transport; 4) patient required emergency transport; and 5) indeterminate. Reliability of the SIRI was assessed using percent agreement among individual panels and weighted kappa for the two panels. Interitem consistency of the SIRI was measured by Cronbach's alpha. Criterion validity was assessed by comparing percent agreements between the SIRI and Medicare reimbursement guidelines. RESULTS: Percent agreement among individual panel members was 62%. Percent agreement among the two panels was 74%, with a kappa of 0.43. Cronbach's alpha for individual panel member item response ranged from 0.647 to 0.960. Percent agreement with Medicare reimbursement guidelines was 92%. CONCLUSION: Consensus criteria and an associated SIRI were developed for determining the appropriateness of NETs. Further research is needed to build on the validity and reliability of this instrument.

Aged↗

A preliminary study of the reliability of immediate vs. delayed interviews of cardiac arrest witnesses.

INTRODUCTION: Methods to characterize the interval between a collapse from cardiac arrest until a 911 call is made have not yet been developed. OBJECTIVE: To determine the concordance of cardiac arrest data obtained by two methods: an immediate nurse interview of out-of-hospital cardiac arrest (OHCA) witnesses, and a follow-up phone interview performed two weeks later. METHODS: This was a prospective study of OHCA witnesses dating from January 1997 to May 1998. Witnesses were briefly interviewed at the time of emergency department presentation, and two weeks later a more lengthy structured phone interview was performed. The authors identified key data elements: 1) was the arrest witnessed? (Wit); 2) was CPR administered prior to EMS arrival? (BCPR); 3) was the first call placed to 911? (c911); and 4) was the estimated collapse to call interval <4 minutes? (ECCI). The analysis utilized Cohen's kappa statistic and Spearman's correlation coefficient. RESULTS: A convenience sample of 42 matched pairs of OHCA cases was analyzed. Kappa statistics for agreement between methods were: 1) Wit(kappa = 0.750), 2) BCPR(kappa = 0.892), 3) c911 (kappa = 0.892), and 4) ECCI(kappa = 0.571, Spearman's 0.528). CONCLUSION: There is good to excellent agreement between immediate and phone interview data retrieval methods. Phone interviews appear to yield data comparable to that with the more difficult and expensive, direct interview method.

Aged↗

The reliability of prehospital clinical evaluation for potential spinal injury is not affected by the mechanism of injury.

INTRODUCTION: Traditional EMS teaching identifies mechanism of injury as an important predictor of spinal injury. Clinical criteria to select patients for immobilization are being studied in Michigan and have been implemented in Maine. Maine requires automatic immobilization of patients with "a positive mechanism" clearly capable of producing spinal injury. OBJECTIVE: To determine whether mechanism of injury affects the ability of clinical criteria to identify patients with spinal injury. METHODS: In this multicenter prospective cohort study, EMS personnel completed a check-off data sheet for prehospital spine-immobilized patients. Data included mechanism of injury and yes/no determinations of the clinical criteria: altered mental status, neurologic deficit, evidence of intoxication, spinal pain or tenderness, and suspected extremity fracture. Hospital outcome data included confirmation of spinal injury and treatment required. Mechanisms of injury were tabulated and rates of spinal injury for each mechanism were calculated. The patients were divided into three different high-risk and low-risk groups. RESULTS: Data were collected for 6,500 patients. There were 209 (3.2%) patients with spinal injuries identified. There were 1,058 patients with 100 (9.4%) injuries in the first high-risk mechanism group, and 5,423 patients with 109 (2%) injuries in the first low-risk group. Criteria identified 97 of 100 (97%) injuries in the high-risk group and 102 of 109 (94%) in the low-risk group. Two additional data divisions yielded identical results. CONCLUSION: Mechanism of injury does not affect the ability of clinical criteria to predict spinal injury in this population.

Adult↗