[Stroke always with an emergency physician? - Pro]

Good management of acute stroke is dependent on time and expertise. In Germany emergency medical care by ambulance services sometimes occurs without an emergency physician being sent to the scene. By reviewing current literature the question of patient care in the ambulance with or without an emergency physician is discussed. Presence of an emergency physician at the scene results in high diagnostic accuracy, allows for invasive procedures to be carried out, and enables referral to a specialist centre with a stroke-unit. The "rendezvous" system of separate deployment of patient ambulance and emergency physician allow flexible assignment of the physician resulting in short response times. Current research does not support a turn away from the deployment of an emergency physician in cases of acute stroke.

[Reducing medical error and improving patient safety]

Within the last years in the public discussion medical error became a new issue. Several studies have addressed problems in the delivery of medical services, which create a breakdown of trust in doctors and the health care system. One of the reasons may be a broader and faster (global) information network system together with media which search extensively for mistakes and problems, despite the fact that diagnostic and therapeutic methods, skills and accuracy could be improved. Nevertheless, the medical system has to address these challenges in order to definitively reduce medical errors and improve patient safety. In contrast to the discussion about quality assurance and management systems in health care, medical errors and patient safety do not have the smell of expensive or not really necessary products, but they are urgent and very important. So the topics "medical error" and "patient safety" have in fact the potential to enhance quality management systems (QMS), which are an accepted technology to solve these problems.

Early intravenous thrombolysis for acute ischemic stroke in a community-based approach

BACKGROUND AND PURPOSE

Controlled multicenter studies have demonstrated the efficacy of systemic recombinant tissue-type plasminogen activator (rtPA) treatment in selected cases of acute ischemic stroke. The feasibility of this therapeutic option in clinical practice was assessed in a community-based approach.

METHODS

We offered rtPA treatment to stroke patients in a prospective open-label monocenter study applying inclusion criteria similar to those of the National Institute of Neurological Disorders, and Stroke study. In order to treat patients within 3 hours of symptom onset, a referral system was used by which eligible patients from all over the city of Cologne, Federal Republic of Germany, were rushed to the Department of Neurology of the University Hospital. We present data on the effectiveness of the referral system and the outcome results of the first 100 consecutive patients treated within an 18-month period.

RESULTS

Of 453 consecutive patients with a presumed diagnosis of acute stroke referred to our department between March 1996 and August 1997, 100 patients (22%) were treated with intravenous thrombolysis, 26% of them within 90 minutes of symptom onset. The average time from stroke onset to arrival at our department was 78 minutes, and from arrival to treatment 48 minutes. After 3 months, 53 patients recovered to fully independent function. The rates of total, symptomatic, and fatal intracerebral hemorrhage were 11%, 5%, and 1%, respectively. Overall mortality was 12%.

CONCLUSIONS

Thrombolysis with rtPA was effectively applied in routine management of stroke patients in a community-based approach with acceptable efforts and without additional costs. Under these circumstances, outcome and complication rates were comparable to those of multicenter trials.

[Recommendations for the conversion of scientific information into practice-relevant guidelines for emergency care in the city of Cologne. Conception of an 8-step program]

Guidelines for prehospital emergency care within the chain of rescue are recommended. At the scene, information about the patient and therapeutical tools are limited. Accidents and emergencies happen outside of hospitals and doctor's offices, while environmental factors and logistic problems strongly determine the rescue process. The sequence of interventions or the choice of the right hospital with specific triage criterias are only examples for these problems. There is only limited scientific evidence for therapies performed prehospitally. However, scientific material for the preparation of guidelines should be evaluated by using standardized criteria. The rules of evidence based medicine according to Cook are a practical way to evaluate and classify scientific material and to establish practical guidelines. In this paper, an 8-step-program is introduced to develop practical guidelines for the Emergency Medical Services Cologne.

H1-antagonism improves intestinal mucosal pH and heart function in porcine hypodynamic endotoxic shock

Porcine hypodynamic shock was induced by continuous infusion of 5 micrograms lipopolysaccharide/kg per hour. This resulted in a decrease of cardiac output from baseline values of 3.5 +/- .9 L/min to 1.5 +/- .8 L/min and a reduced left ventricular stroke work index in the endotoxin-group (n = 6 animals). Pretreatment with the H1-antagonist dimethindene (2 mg/kg) in a second group (n = 6) significantly prevented these effects. Furthermore animals pretreated with the H1-antagonist showed a stable mean arterial blood pressure, whereas the control endotoxin-treated group revealed a drastic reduction in mean arterial blood pressure (99 +/- 4.7 mmHg versus 65.8 +/- 10 mmHg after 240 min, respectively). Pulmonary function and systemic vascular resistance were not ameliorated by the H1-antagonist in hypodynamic shock. Gastrointestinal mucosal pH (pHi), which indicates oxygenation of the mucosa, was decreased by endotoxin-infusion (7.45 +/- .32 baseline value to 6.92 +/- .24 after 120 min). This parameter as well as base excess values and lactate levels were significantly improved by dimethindene-pretreatment (p < .05). These results may indicate a beneficial effect of H1-antagonist-pretreatment on endotoxin-induced deterioration of the microcirculation. Furthermore our results clearly demonstrated that only pretreatment before endotoxemia with H1-antagonism is effective, since infusion of H1-antagonist in hypodynamic shock 45 min after addition of endotoxin (n = 6 animals) did not improve the cardiovascular system or the microcirculation.

Resuscitative hypothermia

Resuscitative (postinsult) hypothermia is less well studied than protective-preservative (pre- and intra-arrest) hypothermia. The latter is in wide clinical use, particularly for protecting the brain during cardiac surgery. Resuscitative hypothermia was explored in the 1950s and then lay dormant until the 1980s when it was revived. This change occurred through the discoveries of brain damage mitigating effects after cardiac arrest in dogs, and after forebrain ischemia in rats, of mild (34 degrees C) hypothermia (which is safe), and of benefits derived from moderate hypothermia (30 degrees C) after traumatic brain injury or focal brain ischemia in various species. The idea that protection-preservation or resuscitation by hypothermia is mainly explained by its ability to reduce cerebral oxygen demand has been replaced by an increasingly documented synergism of many beneficial mechanisms. Deleterious chemical cascades during and after these insults are suppressed even by mild hypothermia. Prolonged moderate hypothermia carries some risks, e.g., arrhythmias, infection and coagulopathies. These side effects need further study. In global brain ischemia, protective-preservative mild hypothermia provides lasting mitigation of brain damage. Resuscitative mild hypothermia, however, may be beneficial in terms of long-term outcome or may merely delay the inevitable loss of selectively vulnerable neurons. Even if the latter is true, mild hypothermia may extend the therapeutic window for other interventions. This extension of the therapeutic window requires further documentation. After normothermic cardiac arrest of 11 mins in dogs, mild resuscitative hypothermia from 15 mins to 12 hours after reperfusion plus cerebral blood flow promotion normalized functional recovery with the least histologic damage seen thus far. Optimal duration of, and rewarming methods from, resuscitative hypothermia need clarification. The earliest possible induction of mild hypothermia after cardiac arrest seems desirable. Head-neck surface cooling alone is too slow. Among many clinically feasible rapid cooling methods, carotid cold flush and peritoneal cooling look promising. After traumatic brain injury or focal brain ischemia, which seem to still benefit from even later cooling, surface cooling methods may be adequate. Resuscitative hypothermia after cardiac arrest, traumatic brain injury, or focal brain ischemia should be considered for clinical trials.

Duration of antibiotic treatment in surgical infections of the abdomen. Minimal antibiotic therapy: technology assessment instead of clinical trials

In modern medicine which already uses maximal resources, additional improvements involve huge extra efforts. With increasing complexity of diseases, specific treatments have only a limited influence on the "whole process". In complex clinical situations (including sepsis and SIRS) the available methodology to identify groups of patients who may benefit from a specific treatment are weak. This is why prospective randomised "megatrials" may be needed to detect small differences in outcome. We suggest that careful prospective assessment of cohorts of well stratified patients, subjected to a specific and standardised treatment, may replace prospective controlled trials.

[Assessment of critical care costs of an intensive care unit with TISS (Therapeutic Intervention Scoring System)--an economic analysis of intensive care]

The parallel documentation of Apache II and TISS scores on a surgical intensive care unit allows detailed cost-effectiveness analyses. 929 patient were observed over 18 months with an average Apache score of 12.8 and 32.3 TISS points per patient-day. A value of 44.46 DM per TISS point resulted from a detailed cost analysis.

Effect of H1-antagonism on cardiovascular, pulmonary, and immunological dysfunction in porcine endotoxic shock

The definite role of histamine in early hyperdynamic septic shock is not yet clear. Therefore a randomized, controlled, blind trial was performed to investigate the effect of the H1-antagonist dimethindene in hyperdynamic porcine shock. Lipopolysaccharide (LPS) infusion (5 micrograms/kg/h) in anesthetized pigs (n = 6) in the control-group induced a hyperdynamic shock state with a decrease in mean arterial blood pressure, and systemic vascular resistance (SVR), and an increase in mean arterial pulmonary pressure and pulmonary vascular resistance (PVR). In the verum group (n = 6) dimethindene (2 mg/kg) administered 15 min before LPS application prevented the decrease in SVR significantly (p < .05) and ameliorated the increase in MPAP and PVR. The impairment in pulmonary function, as measured by the oxygenation ratio (PaO2/FiO2) in LPS-treated animals, was reduced by the H1-antagonist (p = .01). Tissue oxygenation was ameliorated by the H1-antagonist treatment, as demonstrated by plasma lactate levels and base excess values (p < .05, control group versus dimethindene group). The increase in tumor necrosis factor alpha by LPS infusion was not influenced by H1-antagonist pretreatment. The early decrease in SVR did not correlate with an enhanced nitric oxide formation, as measured by nitrate/nitrite plasma levels.

Helicopters as part of a regional EMS system--a cost-effectiveness analysis for three EMS regions in Germany

With increasing health care costs the use of rescue helicopters is being questioned on the grounds of expense. No data exist on the cost-effectiveness of the use of rescue helicopters as part of a regional EMS. The end-point of this study was to analyse the cost-effectiveness of a 15 min response time (state regulation) of advanced life support (ALS) equipment provided by helicopter (1,575,000 DM annual costs) versus a ground-based ambulance (1,004,000 DM annual costs) in three EMS systems (50 km radius) with differing demographic and geographic features in Germany. The effect of varying the ratio of helicopters to ground-based vehicles (ALSC) has also been considered using two additional models. In model 1 each region was allocated one additional helicopter and had six ALS cars removed (daytime only). This improved the response times and saved nearly 1,500,000 DM per year. In model 2 each region had its existing helicopter withdrawn and replaced with six ALS cars. This made response times longer and increased expenditure. In conclusion, the additional use of rescue helicopters in EMS regions (50 km radius) remains cost-effective up to an ALSC:helicopter cost ratio of 1:6.

Beneficial effect of H2-agonism and H1-antagonism in rat endotoxic shock

Although histamine release is generally considered harmful in endotoxic shock, several data exist to doubt this view. Own previous studies in rats let us assume a possible beneficial effect only with H1-antagonists, however a detrimental effect on survival with H2-antagonists. Consequently H1- and H2-agonists and antagonists were studied to prove the hypothesis of a beneficial H2-agonistic and H1-antagonistic effect. Two randomized studies were performed in a standardized rat endotoxic shock model (45 mg of Escherichia coli endotoxin/kg body weight (b.w.)). In both, methylprednisolone (50 mg/kg b.w.) and saline were used as positive and negative controls, respectively. Study I compared the effects of H1- and H2-agonists (betahistine, .1 mg/kg/h, and impromidine, 100 micrograms/kg/h) with H1- and H2-antagonists (astemizole and famotidine both 1 mg/kg b.w.; 20 rats/dose). Study II was performed to estimate the dose-response relationship of a new, highly potent H2-agonist with additional H1-antagonistic features (BU-E 75: .01, .1, 1.0, 10, and 100 micrograms/kg/h; 20 rats/dose). Animals receiving impromidine or BU-E 75 all received omeprazole (1 mumol/kg b.w.) to suppress gastric acid secretion. In study I impromidine significantly increased the survival-time and -course compared to famotidine treated animals (p = .01 and p < .05). Study II showed a positive dose-response relationship of BU-E 75 with an increase in survival rates from 30% (.01 microgram/kg/h) to 70% (100 micrograms/kg/h). These data strongly support the hypothesis of a beneficial effect of H2-agonism and H1-antagonism on survival parameters in rat endotoxic shock.

Evolution of rescue systems: a comparison between Cologne and Cleveland

INTRODUCTION

Comparisons of different emergency medical services (EMS) systems often are reduced to simple comparisons between distinct facilities or strategies (e.g., prehospital physician versus paramedic, "scoop and run" versus "stay and play").

METHODS

The EMS systems of similar cities (Cologne and Cleveland) in two different countries (Germany and the United States) are compared. The comparison is seen from the perspective of an evolutionary standpoint that reflects the development of the EMS system in connection with the special environments. Data on rescue times, facilities, and (trauma) outcomes are compared.

RESULTS

No statistically significant differences in outcome between the systems were detected.

CONCLUSION

Both systems are developed in special environments and are optimized over decades, which explains the similarities in outcome.

Prehospital detection of uncontrolled haemorrhage in blunt trauma

The field strategy for trauma victims is still controversial. The first randomized study in penetrating truncal trauma by Martin et al. (1992) supported experimental findings (Gross et al., 1988, 1989; Kowalenko et al., 1992; Krausz et al., 1992b) that fluid therapy in uncontrolled haemorrhage increases mortality. No controlled data in blunt trauma are available. In this retrospective analysis of blunt trauma victims (n = 353), the parameters systolic blood pressure, capillary refilling time and Traumascore (Champion et al., 1981) were evaluated in the prehospital detection of uncontrolled bleeding. With the CART methodology (Breiman et al., 1984) systolic blood pressure (BP) was the most sensitive parameter. Uncontrolled haemorrhage was found in nearly 50% of patients whose BP was below 90 mmHg and in 66% of those whose BP was below 50 mmHg. An accompanying traumatic brain injury (TBI) impaired the ability of BP to detect uncontrolled bleeding. Future studies evaluating prehospital fluid therapy in severe blunt trauma with a mixture of injuries, should take into account that BP in our study population classified less than 50% patients with uncontrolled haemorrhage.

Prehospital care of burns: an analysis of 3 years use of the emergency physician system (EPS) Cologne

Little information is available about the vital parameters of burns victims shortly after the accident. Therefore cases of burns, electrical and caustic injuries presenting to the Cologne Emergency Physician System over 3 years (n = 262) were prospectively studied and analysed. The average incidence in Cologne, Germany (population 1 million), of burns victims attended by the Emergency Medical System and emergency physicians at the scene was 74 adults and 14 children per year. Children are mainly injured by scalds (41.4 per cent); adults by fire accidents (43 per cent). A classification of the victims at the site of the accident according to their vital signs (Trauma Score (TS) after Champion H. R., Sacco W. J. and Carnazzo A. J. et al. (1981) Trauma Score. Crit. Care Med. 9, 672) showed, that in spite of a major burn injury, the vital signs were usually not or only slightly impaired. Subsequent measurements instituted by the emergency physician at the scene increased with decreasing initial TS. With TS = 14, 50 per cent of the patients were intubated; below 14 points nearly 100 per cent. The fluid administered also increased with a decreasing TS.

Assessment of emergency care in trauma patients

There are many reasons for evaluation of an emergency care system, such as expenses (1.035 Bio. DM in 1985) and quality control. From January 1, 1987 to December 31, 1987 information on all patients seen by an emergency physician in the field have been recorded prospectively in a standard form by the Cologne emergency medical services. Cologne has 1,000,000 inhabitants and covers an area of 405 km2. The patients' status, diagnosis and therapeutic interventions were recorded. Trauma patients were further assessed as to time of accident, cause of accident, and trauma score. All trauma patients with a trauma score < 16 were followed up to their discharge from the hospital. In 1987, 2,073 trauma patients were treated. Overall mortality at the time of discharge was 9.2%. This result alone, however, is not sufficient for assessment of the trauma system. It is important to provide better information on the patient. The trauma evaluation score already used in the US became also a valid instrument in West-Germany. It shows a high correlation between survival and the patients' physiological status in the field. Standard curves could be established for comparing individual or regional trauma systems.

[Multiple trauma: preclinical needs, transportation, time sequences]

Compared to the magnitude of the trauma problem few precise data exist on prehospital care of trauma patients. The aim of the study was the collection and careful evaluation of prehospital data on trauma patients concerning time sequences, patients' status and prehospital interventions. From 1. 1. 1987 to 31. 12. 1990 all 49,045 prehospital emergencies in Cologne were prospectively registered. 8792 trauma patients were treated by an emergency physician in the field. 9.5% were severely injured, defined by a trauma score less than or equal to 12. 9.9% of the trauma patients were intubated, 54.9% received an i.v. line, and 20.6% were triaged to a trauma center. Our data form a valid base for analysis of the effectiveness of prehospital trauma care.

Pharmacotherapy in shock syndromes: the neglected field of pharmacokinetics and pharmacodynamics

Promising effects of adjuvant drugs in experimental shock models often are not confirmed in subsequent clinical trials, e.g., steroids, fibronectin, naloxone, immunotherapeutics. A key difficulty in establishing a therapeutic benefit in clinical studies, apart from study design shortcomings, is the lack of knowledge and application of principles of clinical pharmacokinetics and -dynamics. In shock states the relationship between an administered fixed dose regimen and the drug effect is strongly influenced by dynamic changes in absorption, distribution, metabolism, and elimination of the drug, all of which vary between individual patients. This article describes several neglected aspects of clinical pharmacology relevant to shock research under clinical conditions and discusses the indications, prerequisites, and limitations of "applied pharmacokinetics." The inclusion of therapeutic drug monitoring in clinical shock studies should be applied more frequently to establish experimental results in the "real world" of ICU settings.

Nonsuture microsurgical vessel anastomosis using an absorbable cuff

The nonabsorbable cuff used for nonsuture anastomosis can cause residual vessel stenosis as well as regional wall rigidity. Resulting disturbances in laminar flow promote the development of irregularities in the intimal endothelial vessel lining distal to the anastomosis. Using absorbable cuffs, the degree of stenosis can be appreciably reduced, thereby diminishing thrombogenic flow turbulence. The absorbable cuff can thus facilitate clinical application of nonsuture microsurgical vessel anastomosis.

Atresia of the right atrial ostium of the coronary sinus

A case of asymptomatic congenital occlusion of the ostium of the coronary sinus is described. The myocardial venous drainage was maintained via a persistent left superior vena cava as well via ectatic, widened atrial veins of the dorsal wall of the left atrium. The study shows that complete ostial occlusion of the coronary sinus does not reduce cardiac venous drainage. The view of the literature allows a comparison with the comprehensive classification of coronary sinus anomalies.