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D R Hess

Publications and source records attributed to D R Hess.

30 records · Page 2Linked to original sources

An evaluation of automated defibrillation and manual defibrillation by emergency medical technicians in a rural setting.

We show that automated external defibrillation training of emergency medical technicians (EMTs) is less time consuming than manual defibrillation training, and hypothesize that both improve survival from sudden cardiac death. Data on 91 cardiac arrests over 27 months among five basic life support services was collected before EMT-defibrillation (EMT-D) training. Subsequently, seven BLS services were trained in EMT-D using either manual difibrillation or automated external defibrillation technology, and 55 sudden cardiac death patients were entered after training. Manual defibrillation required 11 more hours per student in initial training. Survival to hospital discharge improved from two of 91 patients (2.2%) in the series before EMT-D training to nine of 55 patients (16.4%) after EMT-D training (P = .001). Improved survival was correlated with shorter prehospital defibrillation times, 8.84 minutes, when EMTs performed defibrillation versus 16.3 minutes before training when EMTs awaited advanced life support defibrillation (P < .001). To enhance equipment familiarity we allowed EMTs to apply three-lead electrode monitors to all medical/cardiac patients during transport (surveillance). There were six emergency medical service-witnessed "surveillance" arrests and three arrests survived to hospital discharge (50% survival). This group represented 33% of all survivors in the series. We recommend automated external defibrillation training for EMTs. Improved survival in sudden cardiac death cases in well-run emergency medical service systems should result from EMT-D training. Finally, we recommend that routine "surveillance" of high-risk patients during transport by defibrillation-capable EMTs be considered in EMT-D programs, rather than limiting EMT-D only to units capable of rapid "man-down" response.

Aged↗

Out-of-hospital cardiac arrest: a six-year experience in a suburban-rural system.

All out-of-hospital cardiac arrest advanced life support (ALS) trip sheets were collected from January 1980 through December 1985 for this suburban-rural system. Information was extracted according to a uniform reporting format. In our study, 18% of patients with early CPR (less than four minutes) and early ALS (less than ten minutes) survived to hospital discharge, compared with 7% with early CPR and late ALS, 6% with late CPR and early ALS, and 3% with both occurring late. Although 75% of the survivors had ventricular tachyarrhythmias as initial rhythms, bradyasystolic arrests were not uniformly lethal, even with long CPR and ALS times. This study supports the need for early CPR in the prehospital care of potential sudden-death victims. We recommend, with qualification, this reporting format to emergency medical services systems to describe their cardiac arrest experience.

Adult↗

Noninvasive transcutaneous cardiac pacing in prehospital cardiac arrest.

This study evaluated the efficacy of prehospital external cardiac pacing in cardiac arrest patients. From October 1984 to June 1985, 91 patients were paced. Mean time from cardiac arrest to advanced life support (ALS) intervention in this metropolitan-rural ALS system was 14.5 minutes. Electrical capture occurred in 85 (93%), mechanical capture (pulses) occurred in ten (11%), and a measurable blood pressure occurred in three (3%) of the 91 patients. Despite a high rate of electrical capture, palpable pulses were produced only in 11%, and no patients survived to be discharged from the hospital. There was no difference in the frequency of electrical capture, palpable pulses, or outcome for patients receiving pharmacologic intervention before or after pacing. Likewise there was no difference in the frequency of electrical capture, palpable pulses, or outcome for patients receiving ALS therapy within or after ten minutes of their arrest. Although we found that external cardiac pacing was easily used in the prehospital setting, pacing did not result in any increase in survival in cardiac arrest patients.

Adult↗

Continuous Fick cardiac output compared to thermodilution cardiac output.

A system has been developed to monitor continuously the components of the oxygen Fick equation: oxygen consumption by a gas exchange analyzer and arteriovenous oxygen difference by pulse and fiberoptic oximetry. A computer-based system was developed which calculates cardiac output and other variables every 20 sec. Continuous Fick (CF) cardiac output was compared to thermodilution (TD) cardiac output in 21 ventilated post-cardiac surgery patients. A total of 237 simultaneous cardiac output measurements had a range between 2 and 11 L/min. The correlation between CF and TD cardiac outputs was r = .86, with an equation of TD cardiac output = 0.92 CF cardiac output + 1.16. There was a significant (p less than .001) difference between the two methods of cardiac output estimation. The CF method was consistently lower than TD; this difference was greater at lower flows. CF cardiac output measurement is practical; it offers distinct advantages in viewing cardiac output together with oxygen demand and oxygen extraction.

Cardiac Output↗

Blunt trauma to the common femoral artery.

A patient with blunt trauma to the groin presented with pain and swelling and was noted to have a bruit and thrill over his right femoral artery. Arteriogram revealed a tear of the endothelium of the common femoral artery. Nonoperative therapy was initiated with continued improvement such that repeat arteriogram 2 months later showed only minimal intimal irregularity, and at 1 year postinjury the patient was asymptomatic.

Adult↗

Early defibrillation program: problems encountered in a rural/suburban EMS system.

Many studies have shown improved survival of cardiac arrest patients by the use of early defibrillation (EMT-D) in the field. This prospective study was the first in Pennsylvania and was undertaken to determine if an EMT-D program would be successful in our suburban/rural setting. One hundred two EMTs were trained to use a semi-automatic defibrillator and data were collected over 16 months. There were 96 cardiac arrests, with only 33 patients (34%) presenting with initially treatable dysrhythmias--ventricular fibrillation (VF) or tachycardia (VT). Twenty-three patients (24%) were admitted to the hospital; survival to hospital discharge occurred in only 5 patients (5.2%). Survival to hospital admission was higher among VF/VT presenting rhythms (36%) than for those with other rhythms (17%, P = 0.07), but survival to discharge among VF/VT rhythms (9%) was not statistically different from other rhythms (3%, P = 0.45). Among VF/VT patients, survival to discharge was correlated with shorter call to first defibrillation intervals. Mean call to response interval was longer than in other reported studies (7.2 +/- 4.3 minutes). In addition, there was a high drop-out rate of EMT participants, no central/uniform early access system (that is, 911), and a lower rate of CPR than reported in other studies. It is concluded that introduction of an EMT-D program without careful analysis of systems response factors will not lead to the improved cardiac arrest survival percentages that have previously been reported.

Adult↗

Prehospital use of a prototype esophageal detection device: a word of caution!

OBJECTIVE: To determine the effectiveness of a prototype esophageal detection device (EDD) during use in the prehospital setting. DESIGN/SETTING: Prospective convenience sample in a prehospital setting. POPULATION: Intubated adult patients. INTERVENTIONS: The study device was used to determine esophageal or endotracheal placement of endotracheal tubes in intubated patients. Clinical means were used to confirm tube location. A data sheet was completed for each patient. RESULTS: Of 105 uses of the device, 17 of 17 esophageal tubes were identified correctly (100% sensitivity). Sixty-five of 88 tracheal tubes were correctly identified (78% specificity). There was intermediate reinflation of the device on 13 of the 65 tracheal tubes. Five tests were indeterminate. There were no false negatives (negative predictive value 100%), but 18 false positives (positive predictive value 48%). CONCLUSION: This prototype EDD adequately identifies esophageally placed endotracheal tubes. Correct identification of endotracheally placed tubes was less sensitive. Much work needs to be done regarding the use of negative aspiration devices to identify placement of endotracheal tubes.

Adolescent↗

Pulmonary epitheloid hemangioendothelioma: a peculiar rare tumor of vascular origin.

An extremely rare case of pulmonary epitheloid hemangioendothelioma (PEH), previously known as intravascular bronchoalveolar tumor (IVBAT), in a 38-year-old female is presented. This patient had a history of rheumatoid arthritis and bilateral multiple small pulmonary nodules which progressed over the years. The histopathological diagnosis of PEH was confirmed by immunohistochemical stains. Prognosis of this tumor is very unpredictable. There is no effective treatment for pulmonary epitheloid hemangioendothelioma.

Adult↗