Prehospital initiation of thrombolytic therapy by paramedics, if both feasible and safe, could considerably reduce the time to treatment and possibly decrease the extent of myocardial necrosis in ...patients with acute coronary thrombosis. Preliminary to a trial of such a treatment strategy, paramedics evaluated the characteristics of 2,472 patients with chest pain of presumed cardiac origin; 677 (27%) had suitable clinical findings consistent with possible acute myocardial infarction and no apparent risk of complication for potential thrombolytic drug treatment. Electrocardiograms (ECGs) of 522 of the 677 patients were transmitted by cellular telephone to a base station physician; 107 (21%) of the tracings showed evidence of ST segment elevation.
Of the total 2,472 patients, 453 developed evidence of acute myocardial infarction in the hospital; 163 (36%) of the 453 had met the strict prehospital screening history and examination criteria and 105 (23.9%) showed ST elevation on the ECG and, thus, would have been suitable candidates for prehospital thrombolytic treatment if it had been available. The average time from the onset of chest pain to prehospital diagnosis was 72 ± 52 min (median 52); this was 73 ± 44 min (median 62) earlier than the time when thrombolytic treatment was later started in the hospital.
Paramedic selection of appropriate patients for potential prehospital initiation of thrombolytic treatment is feasible with use of a directed checklist and cellular-transmitted ECG and saves time. This strategy may reduce the extent and complications of infarction compared with results that can be achieved in a hospital setting.
Predictors of outcome in pediatric submersion victims treated by Seattle and King County's prehospital emergency services were studied. Victims less than 20 years old were identified from hospital ...admissions and paramedic and medical examiners' reports. The proportion of fatal or severe outcomes in patients were compared with various risk factors. Of 135 patients, 45 died and 5 had severe neurologic impairment. A subset of 38 victims found in cardiopulmonary arrest had a 32% survival rate, with 67% of survivors unimpaired or only mildly impaired. The two risk factors that occurred most commonly in victims who died or were severely impaired were submersion duration greater than 9 minutes (28 patients) and cardiopulmonary resuscitation duration longer than 25 minutes (20 patients). Both factors were ascertained in the prehospital phase of care. Submersion duration was associated with a steadily increasing risk of severe or fatal outcomes: 10% risk (7/67) for 0 to 5 minutes, 56% risk (5/9) for 6 to 9 minutes, 88% risk (21/25) for 10 to 25 minutes, 100% risk (4/4) for greater than 25 minutes. None of 20 children receiving greater than 25 minutes of cardiopulmonary resuscitation escaped death or severe neurologic impairment. Our rates for saving all victims, particularly victims in cardiopulmonary arrest, are considerably higher than has been reported before the children. Prompt prehospital advanced cardiac life support is the most effective means of medical intervention for the pediatric submersion victim. Prehospital information provided the most valuable predictors of outcome.
To assess the relationship between CSF creatine kinase BB isoenzyme activity (CSF CKBB) and neurologic outcome after cardiac arrest in clinical practice.
CSF CKBB reflects the extent of brain damage ...following cardiac arrest.
To help with prognosis, treating physicians ordered CSF CKBB tests on 474 patients over 7.5 years; 351 of these patients had experienced a cardiac arrest. Assays were performed in one laboratory using agarose electrophoresis. By chart review, we determined awakening status for all patients, defined as the patient having comprehensible speech or following commands.
CSF CKBB was usually sampled 48 to 72 hours after cardiac arrest and was strongly associated with awakening (p < < 0.001). The median was 4 U/l for 61 patients who awakened and 191 U/l for 290 who never awakened. For those who awakened, 75% of CKBB levels were < 24 U/l, and for those who never awakened, 75% were > 86 U/l. The highest value in a patient who awakened was 204 U/l, a cutoff that yielded a specificity of 100% of never awakening but a sensitivity of forty-eight percent. Only nine patients who awakened had CSF CKBB values greater than 50 U/l, and none regained independence in activities of daily living. Only three unconscious patients were still alive at last contact, with follow-up of 63, 107, and 109 months. Using logistic regression, the probability of never awakening given a CSF CKBB result can be estimated as: 1/(1 + L), where L = e raised to (0.1267 - 0.0211 x CSF CKBB U/l).
CSF CKBB measurement helps to estimate degree of brain damage and thus neurologic prognosis after cardiac arrest. However, results of this retrospective study could reflect in part a self-fulfilling prophecy.
The risk of acquiring a sexually transmitted disease as a result of rape is not known, in part because it is difficult to ascertain whether infections were present before the assault or acquired ...during it. To investigate this question, we examined female victims of rape within 72 hours of the assault and again at least one week after the assault. Of the 204 girls and women initially examined within 72 hours of the rape, 88 (43 percent) were found to have at least one sexually transmitted disease. These diseases included infections caused by Neisseria gonorrhoeae (6 percent of those tested), cytomegalovirus (8 percent), Chlamydia trachomatis (10 percent), Trichomonas vaginalis (15 percent), herpes simplex virus (2 percent), Treponema pallidum (1 percent), and the human immunodeficiency virus type 1 (HIV-1; 1 percent) and bacterial vaginosis (34 percent). Among the 109 patients (53 percent) who returned for at least one follow-up visit (excluding those who were found to be infected at the first visit or who were treated prophylactically), the incidence of new disease was as follows: gonorrhea, 4 percent (3 of 71); chlamydial infection, 2 percent (1 of 65); trichomoniasis, 12 percent (10 of 81); and bacterial vaginosis, 19 percent (15 of 77). There were no new infections with herpes simplex virus, cytomegalovirus, Trep. pallidum, or HIV-1, but follow-up serologic testing was performed in only 26 percent of the patients. On the basis of our assumptions that most venereal infections present within 72 hours of a rape were preexisting and that new infections identified 1 to 20 weeks later were acquired during the assault, we conclude that the prevalence of preexisting sexually transmitted diseases is high in victims of rape and that they have a lower but substantial additional risk of acquiring such diseases as a result of the assault.
Genetic factors may influence outcome from cardiac arrest. In Seattle, WA, paramedics collected blood specimens from patients who had suffered cardiac arrest outside of a medical institution (out of ...hospital cardiac arrest). We examined associations between apolipoprotein E (APOE) genotype and outcome in 134 who died “in the field”, 131 who died in the hospital, 198 patients who were discharged from hospital alive, and 64 control subjects. APOE genotype was not significantly related to outcome, including being alive at and being independent by 3 months after the arrest. Specifically, having one or two alleles of APOE ε4 or having APOE ε3/ε3 was not related to outcome, even after controlling for age, sex, race, and initial rhythm. We failed to confirm previous studies and found no significant associations between APOE genotype and outcome from out of hospital cardiac arrest.
Does the common practice of infusing small amounts of glucose after cardiopulmonary arrest worsen neurologic outcome?
A community-based randomized trial in Seattle, WA. Paramedics treated all ...patients with out-of-hospital cardiac arrest in a standard fashion except that the intravenous infusion did or did not contain glucose; ie, patients received either usual treatment, with 5% dextrose in water (D5W), or alternative, with half normal saline (0.45S).
The main outcome was awakening, defined as the patient having comprehensible speech or following commands as determined by chart review. Other outcomes were survival to hospital admission and to discharge.
Over 2 years, paramedics randomized 748 patients. The type of fluid administered was not significantly related to awakening (16.7% for D5W versus 14.6% for 0.45S), admission (38.0% for D5W versus 39.8% for 0.45S), or discharge (15.1% for D5W versus 13.3% for 0.45S). As in previous studies, patients whose arrest had likely been on a cardiac basis with initial rhythms of ventricular fibrillation or asystole had admission blood glucose levels significantly related to awakening: mean = 309 mg/dl for never awakening and 251 mg/dl for awakening. Of note, the relation between glucose and awakening was reversed in the remaining patients, who had electromechanical dissociation or noncardiac mechanisms of arrest.
Current practices of using limited amounts of glucose-containing solutions after cardiopulmonary arrest do not need to be changed. Blood glucose level on admission is a prognostic indicator but depends on the type of arrest.
Abstract The advent and incorporation of the air bag into motor vehicles has resulted in the mitigation of many head and truncal injuries in motor vehicle collisions. However, air bag deployment is ...not risk free. We present a case of sodium azide-induced laryngospasm after air bag deployment. An unrestrained male driver was in a moderate-speed motor vehicle collision with air bag deployment. Medics found him awake, gasping for air with stridorous respirations and guarding his neck. The patient had no external signs of trauma and was presumed to have tracheal injury. The patient was greeted by the Anesthesiology service, which intubated him using glidescope-assisted laryngoscopy. The patient was admitted for overnight observation and treatment of alkaline ocular injury and laryngospasm. Although air bags represent an important advance in automobile safety, their use is not without risk. Bruising and tracheal rupture secondary to air bag deployment have been reported in out-of-position occupants. Additionally, alkaline by-products from the combustion of sodium azide in air bags have been implicated in ocular injury and facial burns. Laryngospasm after sodium azide exposure presents another diagnostic challenge for providers. Therefore, it is incumbent to maintain vigilance in the physical examination and diagnosis of occult injuries after air bag deployment.
One hundred ninety-nine patients with out-of-hospital cardiac arrest persisted in ventricular fibrillation after the first defibrillation attempt and were then randomly assigned to receive either ...epinephrine or lidocaine before the next two shocks. The resulting electrocardiographic rhythms and outcomes for each group of patients were compared for each group and also compared with results during the prior 2 years, a period when similar patients primarily received sodium bicarbonate as initial adjunctive therapy. Asystole occurred after defibrillation with threefold frequency after repeated injection of lidocaine (15 of 59, 25%) compared with patients treated with epinephrine (four of 55, 7%) (p less than 0.02). There was no difference in the proportion of patients resuscitated after treatment with either lidocaine or epinephrine (51 of 106, 48% vs. 50 of 93, 54%) and in the proportion surviving (18, 19% vs. 21, 20%), respectively. Resuscitation (64% vs. 50%, p less than 0.005) but not survival rates (24% vs. 20%) were higher during the prior 2-year period in which initial adjunctive drug treatment for persistent ventricular fibrillation primarily consisted of a continuous infusion of sodium bicarbonate. The negative effect of lidocaine or epinephrine treatment was explained in part by their influence on delaying subsequent defibrillation attempts. Survival rates were highest (30%) in a subset of patients who received no drug therapy between shocks. We conclude that currently recommended doses of epinephrine and lidocaine are not useful for improving outcome in patients who persist in ventricular fibrillation.
Survival to hospital discharge was related to the clinical history and emergency care system factors in 285 patients with witnessed cardiac arrest due to ventricular fibrillation. Only the emergency ...care factors were associated with differences in outcome. Both the period from collapse until initiation of basic life support and the duration of basic life support before delivery of the first defibrillatory shock were shorter in patients who survived compared with those who died (3.6 ± 2.5 versus 6.1 ± 3.3 minutes and 4.3 ± 3.3 versus 7.3 ± 4.2 minutes; p < 0.05).
A linear regression model based on emergency response times for 942 patients discovered in ventricular fibrillation was used to estimate expected survival rates if the first-responding rescuers, in addition to paramedics, had been equipped and trained to defibrillate. Expected survival rates were higher with early defibrillation (38 ± 3%; 95% confidence limits) than the observed rate (28 ± 3%).
Because outcome from cardiac arrest is primarily influenced by delays in providing cardiopulmonary resuscitation and defibrillation, factors affecting response time should be carefully examined by all emergency care systems.
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