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D DeBehnke

Publications and source records attributed to D DeBehnke.

14 recordsLinked to original sources

Potential errors in the diagnosis of pericardial effusion on trauma ultrasound for penetrating injuries.

OBJECTIVE: To evaluate ultrasound error in patients presenting with penetrating injury with a potential for pericardial effusion. METHODS: Residents and faculty from an emergency medicine training program at Level 1 trauma center with an active ultrasound program were asked to view digitized video clips of subxiphoid cardiac examinations in patients with chest trauma. Participants were asked to fill out a standardized questionnaire on each video clip asking whether a pericardial effusion was present. Other questions included size of effusion and presence of tamponade. The study also asked participants to rate their confidence in their impressions. Data were analyzed using interquartile ranges and confidence levels. RESULTS: All participants had difficulty distinguishing between epicardial fat pads and true pericardial effusions. The overall sensitivity was 73% and specificity was 44%. Confidence shown by participants in their answers increased with level of training or experience, regardless of whether they were correct or incorrect. Additional views were frequently requested to help decide whether an effusion was present. CONCLUSIONS: A serious potential exists for misdiagnosing epicardial fat pads as pericardial effusion in critically ill trauma patients. Emergency physicians need to be aware of this and should consider one of two suggested alternative methods to improve the accuracy of diagnosis.

Adult↗

The effects of graded doses of endothelin-1 on coronary perfusion pressure and vital organ blood flow during cardiac arrest.

BACKGROUND: Endothelin-1 (ET-1) is a potent vasoconstrictor and has been shown to improve coronary perfusion pressure (CPP) during arrest. The effects of ET-1 on organ blood flow during arrest have not been extensively studied. OBJECTIVE: To investigate the effects of ET-1 on myocardial and cerebral blood flow during cardiac arrest. METHODS: Sixty immature swine were anesthetized and instrumented. The animals were randomized to receive one of three doses of ET-1 (50, 150, or 300 microg) or placebo with/without standard-dose epinephrine (SDE) during cardiac arrest. After a 10-minute period of no-flow ventricular fibrillation (VF), cardiopulmonary resuscitation (CPR) was performed for 3 minutes, followed by drug administration. Placebo or SDE was given every 3 minutes. Myocardial and cerebral blood flow was measured using a fluorescent microsphere technique. RESULTS: Prearrest and CPR variables were not different between groups. Beginning 4 minutes after giving 300 microg ET-1 with or without SDE, CPP was significantly increased compared with SDE alone. Total myocardial blood flow following ET-1 administration was no different than myocardial blood flow following SDE alone. Cerebral blood flow increased 3.5 minutes after administration of 300 microg ET-1 with SDE and reached significance 9.5 minutes after drug administration when compared with SDE alone [92.5 (48.8-117.9) vs 15.6 (7.7-23) mL/min/100 g]. CONCLUSIONS: Three hundred microg ET-1 with SDE increases CPP and improves cerebral blood flow but does not improve myocardial blood flow during cardiac arrest. The peripheral effects of ET-1 significantly improve CPP and cerebral blood flow, but myocardial blood flow is not increased due to coronary vasoconstriction.

Animals↗

Comparison of esophageal Doppler monitor generated minute distance and cardiac output in a porcine model of ventricular fibrillation.

The primary goal of cardiopulmonary resuscitation (CPR) is to increase cardiac output (CO), providing adequate tissue perfusion and oxygenation to maintain normal organ function. A non-invasive, easy to use, commercially available esophageal doppler monitor (EDM, Deltex) has been found to provide minute distance (MD), which is the distance moved by a column of blood through the aorta in 1 min. The goal of our study was to determine if CO measurements correlate with the EDM MD, before and during cardiac arrest, in a porcine model of ventricular fibrillation. Twenty pigs were anesthetized and an EDM was placed. MD measurement using EDM, and CO measurement using florescent microsphere injections were compared before and during CPR. MD correlated well with CO (r2 = 0.96) before and during CPR. Based on the excellent correlation between MD as determined by EDM and CO by florescent microsphere technique, it appears that the non-invasive use of the EDM may play a valuable role in determination of CO during CPR.

Animals↗

Comparison of prehospital monomorphic and polymorphic ventricular tachycardia: prevalence, response to therapy, and outcome.

OBJECTIVE: Monomorphic ventricular tachycardia (MVT) is the most common form of prehospital ventricular tachycardia (VT). Recent literature suggests that polymorphic ventricular tachycardia (PVT) is more common during cardiopulmonary arrest than previously thought but responds poorly to advanced cardiac life support (ACLS) therapy. We undertook this study to determine the prevalence, response to therapy, and outcome of both MVT and PVT in the prehospital sudden cardiac death victim. DESIGN: Retrospective prehospital chart review from 1987 to 1991. SETTING: Municipal, fire department-based, multitiered emergency medical system serving a population of approximately one million. PARTICIPANTS: Adult patients older than 18 years experiencing prehospital, nontraumatic cardiopulmonary arrest with VT occurring at any time during the resuscitation. VT was defined as PVT if the QRS-complex configuration was not stable when viewed in a single electrocardiographic lead (ie, episodic changing of the QRS-complex electrical axis, amplitude, or both or the presence of more than two QRS-complex morphologies). Outcome was defined in terms of both the presence or absence of spontaneous circulation at the end of the prehospital phase of care and ultimate outcome (survival to hospital discharge or death). Four hundred seventy-six patients met entry criteria; 37 patients were excluded because of incomplete medical records, and 439 patients were used for data analysis. INTERVENTIONS: ACLS therapy based on the 1987 American Heart Association guidelines. RESULTS: MVT occurred in 323 patients (73.6%), with 119 (36.8%) showing return of spontaneous circulation (ROSC) in the prehospital setting; 35 MVT patients (10.8%) survived to hospital discharge. PVT occurred in 116 patients (26.4%), with 48 (41.4%) showing ROSC in the prehospital setting; 15 PVT patients (12.9%) survived to hospital discharge. The use of ACLS therapy (defibrillation, endotracheal intubation, medication usage) between the two rhythm groups was not statistically different. The P values for ROSC, ultimate outcome, and use of ACLS therapy were all not significant. CONCLUSION: We conclude that PVT is a common rhythm occurring in prehospital cardiopulmonary arrest that responds as well as MVT to ACLS therapy. Until prospective data are available, standard ACLS therapy should be used in all forms of prehospital VT occurring during cardiopulmonary arrest.

Adult↗

A case-based emergency medicine curriculum for senior medical students.

OBJECTIVE: To determine the effects of a case-based, core content-oriented emergency medicine (EM) curriculum on the basic EM knowledge of senior medical students. METHODS: All senior medical students rotating through the Milwaukee County EM elective during the 1992-1993 academic year were assigned specific chapter readings from a case-oriented EM textbook. A course curriculum consisting of goals and objectives for each chapter and two to three representative cases for the discussion topic also was distributed to each student. Interspersed with the cases was a series of questions directed at pathophysiology, diagnosis, management, and disposition. The EM faculty and residents conducted case discussions three times per week. All students completing the rotation were given a pretest at the beginning and a final examination at the end of the rotation. In addition, the students rated the textbook, coursebook, and lecture series at the end of the rotation using a five-point Likert scale. RESULTS: Seventy-five students rotated through the elective. The students showed a significant improvement in their EM knowledge base as judged by improvement in final examination scores compared with pretest scores (pretest score 62.2 +/- 7.1%; final examination score 76.2 +/- 6.3%; p < 0.0001). The mean change in scores was 14.8%, with a range of -1.6% to 34%. The students also rated the textbook, coursebook, and lecture series as effective, as shown by high median scores on a Likert scale. CONCLUSIONS: A case-based EM curriculum coupled with ED clinical experience improves basic EM diagnostic and management knowledge of senior medical students.

Analysis of Variance↗

Resuscitation time limits in experimental pulseless electrical activity cardiac arrest using cardiopulmonary bypass.

STUDY OBJECTIVE: The objective of this study was to determine the time limits of resuscitation following increasing intervals of untreated pulseless electrical activity using cardiopulmonary bypass as the resuscitation tool. DESIGN: Prospective controlled laboratory investigation using a canine model of pulseless electrical activity. SUBJECTS: 20 mechanically ventilated mongrel dogs of either sex under Halothane anesthesia. INTERVENTIONS: Pulseless electrical activity was produced by clamping the endotracheal tube. The ECG and hemodynamics were monitored until loss of pressure fluctuations by aortic catheter. Animals were then randomized to remain in untreated pulseless electrical activity for 10 min (Group I), 15 min (Group II) or 20 min (Group III). Following each interval, resuscitation was begun using fixed-flow closed-chest cardiopulmonary bypass (50 ml/kg/min) and an epinephrine infusion (4 micrograms/kg/min). Cardiopulmonary bypass was continued for 30 min or until return of spontaneous circulation. Following return of spontaneous circulation, animals were weaned from bypass and observed for 1 h. MEASUREMENTS AND MAIN RESULTS: Return of spontaneous circulation was achieved in 100% (7/7) Group I, 50% (3/6) Group II and 29% (2/7) Group III animals (P < or = 0.02, Group I vs. Group III). One-hour survival was achieved in 71% (5/7) Group I, 33% (1/3) Group II and 0% (0/2) Group III animals (P > 0.05). Coronary perfusion pressure, bypass flow and arterial blood gases during reperfusion were similar between groups. CONCLUSION: Cardiopulmonary bypass is effective at restoring spontaneous circulation when used early in asphyxial pulseless electrical activity cardiac arrest. Cardiopulmonary bypass is less effective when used after 15 min of pulseless electrical activity with no survivors following 20 min of arrest.

Animals↗

Reversible neurological deficits in a chronic alcohol abuser: a case report of Wernicke's encephalopathy.

The abuse of alcohol presents daily challenges for the emergency medicine physician. Wernicke's encephalopathy represents one of the metabolic complications associated with alcoholism. A classic presentation of Wernicke's encephalopathy is reported. The patient presented to the emergency department with the chief complaint of confusion, difficulty ambulating, and visual disturbances. Following administration of intravenous thiamine, the patient's symptoms spontaneously resolved. The pathophysiology, clinical presentation and therapy of this classic disorder are discussed.

Adult↗