ABSTRACTS Peter Rosen,MD
--
editor
Director of the Division of Emergency Medicine, Denver General Hospital
Frank
J. B a k e r ,
II, MD
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assistant editor
Associate Professor and Director, Department of Emergency Medicine, University of Chicago Hospitals and Clinics
Handcuffs and cheiralgia paresthetica. Massey EW, Pleet AB, Neurology 28:1312-1313, (Dec) 1978. Two cases of neuritis of the superficial branch of the radial nerve produced by handcuffs are presented. Cheiralgia paresthetica (hand pain) is a mononeuropathy of the superficial branch of the radial nerve. Both cases presented with numbness over the ulnar aspect of the dorsum of the h a n d with an area of h y p e r p a t h i a along with the u l n a r aspect of the thumb. Both cases presented within 24 hours of the injury and at least one was permanent. The superficial branch of the radial nerve is purely sensory to the dorsal of the hand; it runs parallel to the radial artery on the lateral side until it crosses the pronator teres, where it turns posterior and crosses the dorsal carpal ligament where it divides to its terminal branches. (Editor's note: This syndrome may be more common than we are aware. A contributor may be the struggling drunk who ends up with very tight cuffs both because of swelling and a punitive desire to cause pain by the restrainer. We also tend tooverlook minor complaints in prisoners as part of their desire to get out of jail.) Hal Thomas, MD neuritis, hand; cheiralgia paresthetica
Bystander-initiated cardiopulmonary resuscitation in the management of ventricular fibrillation, Thompson R, Hallstrom A, Cobb L, Ann Intern Med 90:737-740, (May) 1979. More t h a n 200,000 residents of Seattle have been trained in basic CPR. Three hundred sixteen patients were analyzed retrospectively to assess the difference between bystanderinitiated CPR (BICPR) and CPR begun when firemen or paramedics arrived (PICPR). Of the 316, 28% were ultimately discharged home; 34% were initally resuscitated but eventually died in a medical facility. Of significance is the difference in survival and eventual neurologic status of survivors in the two groups. BICPR resulted in a 43% survival r a t e with 50% conscious by hospital arrival; only one of 27 was disoriented and three of the 38 survivors were comatose. Also reduced were intractable shock and neurologic sequelae. Education of all community members in basic CPR would significantly improve survival in cardiac arrest situations and is an important part of a total emergency medical system. (Editor's note: We think CPR should be taught in the school system. The best efforts in the ED are totally dependent on the prehospital care.) Ben Honigman, MD
cardiopulmonary resuscitation, bystander-initiated Lidocaine prophylaxis in acute myocardial infarction, Noneman JW, Rogers JF, Medicine 57:501-515, 1978. The use of lidocaine in the setting of acute myocardial infarction (AMI) is reviewed. Lown in 1967 advocated the use of lidocaine prophylaxis to prevent ventricular fibrillation (VF) in AMI patients in a critical care unit (CCU) who manifested premonitory or warning arrhythmias, specifically: (1) PVCs occurring early in the cycle with interruption of T wave (R' on T phenomenon); (2) two or more consecutive PVCs; (3) multifocal PVCs; (4) more than five PVCs per minute. Although this approach has been essentially standard therapy in most CCUs and in the field and emergency department more recently, investigations have raised the question of the reliability of warning arrhythmias as consistent predictors of VF or patients at risk, and actually failing to warn of impending primary VF in up to 80% of patients with AMI. The incidence of PVF in AMI is 3% to 10% or more, with 60% to 80% of all episodes occurring in the first six hours after onset of symptoms. For effective lidocaine therapy to be used, constant therapeutic blood levels of lidocaine must be achieved; the pharmacokinetics of lidocaine dictate that a loading dose and a constant infusion with monitoring of blood levels are n e c e s s a r y to p r o m p t l y a c h i e v e a n d m a i n t a i n a d e q u a t e therapy. The authors conclude from their review of the literature that lidocaine prophylaxis in all AMI patients, presumably from onset of symptoms, is indicated until more definitive data are available. (Editor's note: Other unanswered questions are the prophylactic use in the field and multiple bolus therapy versus bolus and drip. Our own practice is bolus and drip, but our ambulance runs are short. A higher incidence of lidocaine complications may well occur with longer runs.) Frederick K. Seydel, MD
myocardial infarction, fidocaine 9:2 (February) 1980
Ann
Value of "inconclusive lavage" in abdominal trauma management. Hornyak S, Shafton G, J Trauma 19:329333, (May) 1979. Peritoneal lavage is an important adjunct to physical examination in evaluating the need for exploratory laparotomy in a patient with blunt or penetrating abdominal trauma. Traditionally a red blood count of greater t h a n 100,000 RBC/cu m m of lavage fluid has been the threshold mandating exploration in an otherwise stable patient. The authors of this prospective study evaluated the results of 685 peritoneal lavages with subsequent laparotomy. Through a protocol mandating exploration for RBC counts greater than 5,000 RBC/cu mm they found serious injury in 23% of patients with cell counts from 0 to 20,000, 67% with cell counts from 20,000 to 50,000, 86% with cell counts from 50,000 to 100,000, and finally 95% with cell counts above 100,000. In a group of 398 patients with crystal clear lavage fluid, two patients were explored based on physical examination. Both were found to have serious intraperitoneal injury. John Hurst, MD
injury, abdominal, peritoneal iavage Historic and angiographic features of young adults surviving myocardial infarction. Warren SE, Thompson Sl, Vieweg VR, Chest 75:667-670, (Jun) 1979. Selective coronary cinearteriograms were performed on 68 survivors of myocardial infarction who were under 36 years of age. T h r e e g r o u p s of p a t i e n t s e m e r g e d : t h o s e w i t h atherosclerotic coronary arteries, those with normal coronary arteries, and those with coronary artery anomalies. Fifty-six
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patients (88%), 54 of whom were men, were in the first group. Only 29% had angina prior to the infarct, but 77% had postinfarction angina. Eighteen percent had late ventricular arrhythmias. The incidence of risk factors was high: 8(F/o were smokers, 21% had hypertension, and 52% had a positive family history. All but one of the nine patients with normal coronary arteries were men. Angina was frequent both before and after the infarct, as were ventricular arrhythmias. Risk factors were significant only for smokers (44%). Three patients had coronary artery anomalies: a single left, a single right, and a left coronary artery arising from the pulmonary trunk. The patients never had angina, but two of three developed ventricular arrhythmias. Risk factors were usually absent. The a v e r a g e age a t the time of infarct was 20. Myocardial infarction in young people differs from that in the elderly, for there is a more heterogeneous underlying coronary anatomy, overwhelmingly predominance of male patients, lower incidence of angina, and overall better prognosis. This study suggests that all myocardial infarction patients should be studied in the catheterization laboratory. (Editor's note: The significance for emergency medicine is the increasing numbers of young patients with life-threatening arrhythmias. Whether or not they have anatomical lesions is less important than the need for excellent prehospital care to improve salvage.) Ken Kulig, MD
diac rates. Other studies demonstrate a ventricular fibrillation threshold lowered by increased heart rate or a lower vagal tone. In addition, increased heart rates associated with myocardial ischemia were noted to increase refractory period disparity in contiguous areas of myocardium, resulting in establishment of multiple sites of reentrant activity. Myocardial infaction associated with mild bradycardia and hypotension without peripheral vasoconstriction has a relatively benign prognosis and the routine administration of atropine m a y r e s u l t in t h e e m e r g e n c y of l e t h a l v e n t r i c u l a r arrhythmias. (Editor's note: Although a direct causal relationship between atropine and lethal ventricular arrhythmias has not been demonstrated, the points of this article are well worth considering in patients with mild hypotension and bradycardia. Further research with animal models is necessary to det e r m i n e the f u l l effect of atropine on the ischemic myocardiumJ Steven Koenigsknecht, MD
myocardial infarction, young adults
The use of metronidazole (Flagyl) in a single 2-gm oral dose has recently been reported for the successful t h e r a p y of trichomonal vaginitis and urethritis. Because of the carcinogenicity and mutagenicity of metronidazole in laboratory animals and bacteria, the highest cure rate with the smallest possible dose is desirable. Three patient groups were treated w i t h 2.0 gm, 1.5 gm, or 1.0 gm single oral dose of metronidazole and were studied for effectiveness of eliminating infection and for the incidence of side effects. Cure rates were similar (91%) in all three groups, with fewer side effects in the 1.0 gm dosage group. (Editor's note: It should be remembered that metronidazole and alcohol may produce an antibuse-alcohol type reaction and therefore patients treated with metronidazole should avoid any alcoholic beverages for 24 hours after the last dose.) Brian Allen, MD
Clonazepam. Browne TR, N Engl J Med 299:812-815, (Oct) 1978. Clonazepam, a new antiepileptic drug of the benzodiazepine class, was approved in 1977. It is currently approved by the FDA for use in the following types of seizures: typical petit mal, infantile spasms, atypical petit mal, and myoclonic and atonic seizures. It is not approved for t r e a t m e n t of grand mal, psychomotor, or focal seizures. Intravenous clonazepam is effective for all types of status epilepticus. However it is probably no more effective than diazepam and has as its major toxicity sedation and cardiorespiratory depression. Most comm e n side effects are d r o w s i n e s s , a t a x i a , a n d b e h a v i o r changes. Tolerance with recurrence of seizures may occur after an initially good response. Overdosage can result in drowsiness, ataxia and cyclic coma. To date, all overdoses have recovered without sequelae. (Editor's note: We have seen a number of patients treated for grand mal epilepsy with this drug whose seizures are not well controlled. Perhaps this reflects their difficult seizure diathesis; perhaps a fad for a new drug improperly applied.) Hal Thomas, MD
epilepsy, drug treatment, clonazepam Atropine-induced ventricular fibrillation: case report and review of the literature. Cooper MJ, Abinader EG, Am Heart J 97:225-228, (Feb) 1979. This article presents a case report and review of the literature concerning bradycardia and hypotension in the early phases of myocardial infarction. The authors review a case of inferior diaphragmatic myocardial infarction in a patient with a pulse of 48 beats/min and a blood pressure of 95/70 mm Hg who was treated with 0.5 mg atropine intravenously. Over the following 5 min the pulse increased to a rate of 130 beats/min (sinus) and t h e n d e g e n e r a t e d into v e n t r i c u l a r tachycardia followed by ventricular fibrillation. Several similar case reports of ventricular dysrhythmias following the treatment of bradycardia with atropine are cited. They note t h a t bradycardia with myocardial infarction is associated w i t h a lower incidence of lethal ventricular d y s r h y t h m i a compared to patients with tachycardia or normal heart rates. In addition, recent reports do not demonstrate any increase in n u t r i e n t myocardial blood flow with atropine-induced rapid heart rates and diminished vagal tone. More than one third of patients given careful atropine titration in a Belfast coronary care unit demonstrated inappropriately rapid car-
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atropine, ventricular fibrillation; myocardial infarction, atropine Single-dose metronidazole for trichomonal vaginitis: patient and consort. Dykers JR Jr, Am J Obstet Gyneco/ 129:579-580, (Nov) 1978.
vaginitis, trichomonal, drug treatment The esophageal obturator airway, a clinical comparison to ventilation with a mask and oropharyngeal airway. Bryson TK, Benumof JL, Ward CF, Chest 74:537-539, (Nov) 1978. Comparison of controlled ventilation with the esophageal obturator airway (EOA) to the conventional system of rubber m a s k and o r o p h a r y n g e a l a i r w a y was m a d e in 10 anesthetized patients scheduled for elective surgery under general anesthesia. Values for tidal volume were in all cases smaller with the EOA and in two cases were inadequate for survival. Leakage from the face mask was similar or greater in all cases with the EOA and in edentulous patients was marginal or unacceptable. Supraglottic obstruction was equal or greater in all cases with the EOA. Two of the 10 patients had accidental endotracheal intubation with the airway and required eventual direct laryngoscopic visualization. Placemerit of the EOA was cancelled in a third patient because of resistance to passage. Endotracheal intubation is the procedure of choice for resuscitative airway management. In situations in which it cannot be used, the standard mask and oropharyngeal airway appears to be preferable to the EOA. (Editor's note: This article is intriguing because of the number of complications seen with the esophageal airway. One wonders i f the incidence was so high because of the patients being anesthetized, or i f the lack of familiarity with the equipment played a role. We prefer endotracheal intubation when possible, but see a role for the EOA in the patient with potential neck injury in whom nasotracheal intubation cannot be achieved.) David H. Craig, MD
esophageal obturator airway
Ann Emerg Med
9:2 (February) 1980