Effects of ethanol and naltrexone in a model of traumatic brain injury with hemorrhagic shock.

BACKGROUND: Ethanol predisposes to traumatic injury and causes respiratory depression and cardiovascular compromise in models of traumatic brain injury (TBI) and hemorrhagic shock (HS). Endogenous opioids may play a role in ethanol intoxication and TBI. We studied the effects of ethanol and the opiate antagonist agent naltrexone (NTX) in a TBI/HS model. METHODS: Fifty-six pigs (20 kg) were anesthetized with isoflurane, intubated, instrumented, and subjected to fluid percussion TBI with concurrent 30 ml/kg hemorrhage over 30 min. Seven groups were studied: Control, EtOH, NTX, INJ, INJ/EtOH, INJ/NTX, and INJ/EtOH/NTX. Ethanol (2 g/kg IV) was given preinjury, followed by infusion of 0.4 g/kg/hr. NTX 0.3 mg/kg intravenous was given 5 min postinjury. Parameters monitored for 120 min postinjury included minute ventilation (VE), blood pressure (MAP), cerebral perfusion pressure (CPP), cerebral venous lactate (Lac), arterial and cerebral venous blood gases, and brain tissue PtiO2. RESULTS: Ethanol levels at injury were 220 mg/dL. Ethanol-treated animals had depression of hypercapnic ventilatory response, which was reversed by administration of naltrexone. MAP and CPP were significantly lower in injured animals, but were not significantly improved by NTX. Cerebral venous pH was lower and lactate was higher in ethanol-treated animals. CONCLUSION: In this TBI/HS model, NTX reverses ethanol-induced depression of hypercapnic ventilatory response but does not improve MAP, CPP, or metabolic acidosis. This suggests that the respiratory effects of ethanol in TBI, but not the hemodynamic effects, may be mediated by opiate receptor activation.

Under-resuscitation of near-lethal uncontrolled hemorrhage: effects on mortality and end-organ function at 72 hours.

Laboratory studies of uncontrolled hemorrhage demonstrate that under resuscitation (UR) improves short-term survival, but at the expense of tissue perfusion. The long-term effects of UR have not been studied. The purpose of this study was to evaluate survival and the incidence of end-organ injury (EOI), 3 days following moderate and severe UR of uncontrolled hemorrhage. Thirty-four swine (14-24 kg) were assigned to 4 groups: Groups I, II, and III were hemorrhaged to a pulse pressure = 5 mmHg in the presence of a 4-mm aortic tear: Group I (control; n = 6) was not resuscitated; Group II (n = 11) was severely under resuscitated (MAP [mean arterial pressure] = 40 mmHg) for 75 min; Group III (n = 9) was moderately under resuscitated (MAP = 60 mmHg) for 75 min. After 75 min, the aortotomy was repaired, and animals were resuscitated to baseline physiologic parameters. Group IV (sham; n = 8) was instrumented, but not hemorrhaged. Seventy-two-hour mortality was 100%, 36%, 22%, and 0% for Groups I through IV (P = .001 Fisher's exact). Cardiac indices, serum bicarbonate, and systemic oxygen delivery were significantly lower in Group II as compared to Group III during the 75 min of UR (P < 0.05; repeated measures ANOVA). By 72 h, physiologic parameters in surviving animals had returned to baseline levels. Measures of kidney, liver, neurologic, and pulmonary function did not change from baseline. There was no histologic evidence of EOI. In this model, 75 min of UR did not result in EOI. There was a trend toward greater survival, and tissue perfusion was better preserved with moderate as compared to severe UR.

Development of three African language translations of the FACT-G.

This pilot study investigated the feasibility of translating a quality of life instrument, the Functional Assessment of Cancer Therapy--General version (FACT-G) and the breast cancer version (FACT-B), which consists of the FACT-G plus 10 additional items, into three South African languages (Pedi, Tswana, and Zulu). The international, interdisciplinary research team hypothesized that we could develop reliable and valid translations, and that valuable information could be gleaned from the responses of the three groups of traditional African people, which could inform the Western-trained medical profession. Understanding of cross-cultural views of cancer including its diagnosis and treatment could lead to better communication between the two cultures (Western and Traditional) resulting in increased utilization of Western medical treatment and increased treatment compliance by three of the underserved black populations. A total of 167 respondents completed one of three translated questionnaires, which assessed the patients' quality of life in 5 domains: Physical Well-Being, Social and Family Well-Being, Relationship with Doctor, Emotional Well-Being, and Functional Well-Being, plus for breast cancer patients the additional items on the FACT-B. However, only the items from the FACT-G (the 'core' of the FACT-B) were statistically analyzed for this pilot project. Results showed that it was possible to develop a reliable instrument in the three languages by modifying the standard translation methodology. Translation of physical and functional concepts was most straightforward. Translation of emotional items posed some difficulty. As expected, based upon observations about cultural differences in social values and functioning, the Social/Family Well-Being subscale was problematic. Analysis of this subscale provides information on cultural differences which may be important to physicians desiring to effectively treat this population with sensitivity and dignity. Methodology may be generalizable to other third world patient populations in translation of existing health status questionnaires.

Effect of initially limited resuscitation in a combined model of fluid-percussion brain injury and severe uncontrolled hemorrhagic shock.

OBJECT: Studies of isolated uncontrolled hemorrhage have indicated that initial limited resuscitation improves survival. Limited resuscitation has not been studied in combined traumatic brain injury and uncontrolled hemorrhage. In this study the authors evaluated the effects of limited resuscitation on outcome in combined fluid-percussion injury (FPI) and uncontrolled hemorrhage. METHODS: Twenty-four swine weighing 17 to 24 kg each underwent FPI (3 atm) and hemorrhage to a mean arterial pressure (MAP) of 30 mm Hg in the presence of a 4-mm aortic tear. Group I (nine animals) was initially resuscitated to a goal MAP of 60 mm Hg; Group II (nine animals) was resuscitated to a goal MAP of 80 mm Hg; and Group III (control; six animals) was not resuscitated. After 60 minutes, the aortic hemorrhage was controlled and the animals were resuscitated to baseline physiological parameters and observed for 150 minutes. Mortality rates were 11%, 50%, and 100% for Groups I, II, and III, respectively (Fisher's exact test; p = 0.002). The total hemorrhage volume was greater in Group II (69+/-32 ml/kg), as compared with Group I (41+/-18 ml/kg) and Group III (37+/-3 ml/kg) according to analysis of variance (p < 0.05). In surviving animals, cerebral perfusion pressure, cerebral blood flow (CBF), cerebral venous O2 saturation (ScvO2), and cerebral metabolic rate of O2 did not differ among groups. Although CBF was approximately 50% of baseline during the period of limited resuscitation in Group I, ScvO2 remained greater than 60%, and arteriovenous O2 differences remained within normal limits. CONCLUSIONS: In this model of FPI and uncontrolled hemorrhage, early aggressive resuscitation, which is currently recommended, resulted in increased hemorrhage and failure to optimize cerebrovascular parameters. In addition, a 60-minute period of moderate hypotension (MAP = 60 mm Hg) was well tolerated and did not compromise cerebrovascular hemodynamics, as evidenced by physiological parameters that remained within the limits of cerebral autoregulation.

The effect of a new tissue-adhesive wound dressing on the healing of traumatic abrasions.

BACKGROUND: Octylcyanoacrylate is a new medical-grade adhesive with antimicrobial properties. It forms a thin, flexible, occlusive bandage. OBJECTIVE: To determine the gross and histological effects of the spray bandage when treating abrasions. METHODS: Abrasions were produced on the flanks of 18 albino guinea pigs and randomized to treatment with a control (Biobrane) or octylcyanoacrylate dressing. The wounds were assessed with digital photography using a previously validated method. Histopathological analysis was done on day 14. RESULTS: There were no differences in the mean wound-healing ratios on days 1 (1.25 vs. 1.23, p = 0.61), 7 (1.15 vs. 1.13, p = 0. 14) and 14 (1.03 vs. 1.02, p = 0.63) for tissue adhesive and Biobrane, respectively. There were no differences found on histopathological analysis either. CONCLUSIONS: This external spray bandage was well tolerated and did not show any signs of histotoxicity or adverse wound healing.

Effects of ethanol on brain lactate in experimental traumatic brain injury with hemorrhagic shock.

OBJECTIVE: Previous studies of traumatic brain injury (TBI) and hemorrhagic shock (HS) models, have shown cardiorespiratory depression in ethanol-treated animals. This study investigated the effects of ethanol (ET) on brain lactate concentrations and acidosis in a TBI/HS model. METHODS: Anesthetized swine were instrumented and subjected to injury (INJ) consisting of fluid percussion TBI of 3 atm with concurrent 30 ml/kg graded hemorrhage over 30 min. Three groups were studied: Sham, INJ and INJ/ET. ET was given preinjury as a 2-g/kg i.v. bolus over 30 min, and an infusion of 0.4 g kg(-1) h(-1). Cardiorespiratory and cerebral physiologic data were monitored continuously for 150 min postinjury. Cerebral and renal blood flow was measured with colored microspheres. Brains were frozen in situ with liquid nitrogen. Lactate was measured with an enzymatic method. RESULTS: ET levels at injury were 219+/-24 mg/dl. The INJ/ET group had increased mortality, impaired ventilation, and reduced renal blood flow. Brain (cortical) lactate levels were significantly higher and cerebral venous lactate concentrations were increased in the INJ/ET group during the postinjury period. Cerebral venous glucose was significantly higher in the INJ/ET group, and cerebral venous pH was significantly lower. CONCLUSION: In this TBI/HS model, ethanol-induced increases in lactate concentrations in brain tissue and cerebral venous blood are associated with respiratory depression and reduced organ blood flow.

The impact of environmental factors on emergency medicine resident career choice.

OBJECTIVE: To evaluate the impact of environmental factors on emergency medicine (EM) resident career choice. METHODS: Program directors of all U.S. EM residencies were surveyed in November 1997. A 22-item questionnaire assessed resources allocated to research, fellowship availability, academic productivity of faculty and residents, and career choices of residency graduates. RESULTS: The response rate was 83%. The program director (mean+/-SD) estimates of resident career choice were as follows: 27.8+/-19.1% pursued academic positions with emphasis on teaching, 5.4+/-9.8% pursued academic positions with emphasis on research, and 66.8+/-23.1%, pursued private practice positions. In addition, 5.70+/-6.13% of the residency graduates were estimated to seek fellowship training. Univariate analyses demonstrated that increasing departmental funding for research, having substantial resource availability (defined as having at least two of the following: dedicated laboratory space; support for a laboratory research technician/assistant, a clinical research nurse or study coordinator, a statistician, or an assistant with a PhD degree), a greater number of peer-reviewed publications by residents (r = 0.22; p = 0.08), and a greater number of peer-reviewed publications by faculty (r = 0.26; p = 0.04) positively correlated with the percentage of graduates who pursue academic research careers. Using multiple regression, however, increasing intramural funding and the presence of substantial resource availability were the only variables predictive of resident pursuit of an academic research career. CONCLUSION: Modification of the EM training environment may influence the career choices of graduates. Specifically, greater commitment of departmental funds and support of resources for research may enhance the likelihood of a trainee's choosing an academic research career.

ByOPHTEL: a Bavarian project for rapid telemedical exchange of knowledge, files and skills between practitioners and hospitals in eye care.

ByOPHTEL, part of the Bavarian initiative Bayern Online, derived its name from the European project OPHTEL, to which it is closely linked and which, in Bavaria, is more or less worked out and performed by identical persons and institutions. It provides a group of 7 practitioners in and around the city of Munich with the possibility of exchanging general ophthalmologic knowledge as well as patient-related information with anyone in the group, or with the related ophthalmologic, internal, resp. scientific centers at the TU Munich and the GSF Neuherberg. Connections are routinely performed in the asynchronous or in the synchronous mode, and all partners participate in the scientific projects Knowledge Based Information System, Glaucoma Monitor, and Diabetic Retinopathy Monitor--as well as in the enhancement of a trustful patient-physician relationship ("second opinion") and a closer cooperation in out-patient and in-patient ophthalmical surgery and medical treatment.

Acute ethanol intoxication in a model of traumatic brain injury with hemorrhagic shock: effects on early physiological response.

OBJECT: Traumatic brain injury (TBI) is exacerbated by hypotension and hypoventilation. Because previous studies have shown a potentiating effect of ethanol (EtOH) on TBI and hemorrhagic shock (HS), the authors investigated the effects of EtOH on the early physiological response to TBI with and without HS. METHODS: Anesthetized swine, weighing approximately 20 kg each, underwent fluid-percussion TBI of 3 atm with or without 30 ml/kg hemorrhage for a period of 30 minutes. The mean arterial blood pressure, intracranial pressure, cerebral perfusion pressure (CPP), cardiac output, cerebral venous oxygen saturation, and metabolic parameters were monitored for 3 hours postinjury. Ventilation and the response to hypercapnia were also measured. Regional cerebral blood flow and renal blood flow were measured using dye-labeled microspheres. Five groups were studied: control, TBI, TBI/EtOH, TBI/HS, and TBI/HS/EtOH. The EtOH (3.5 g) was given intragastrically 100 minutes preinjury. The TBI/HS/EtOH group demonstrated a 3-hour mortality rate of 56% and postinjury apnea requiring ventilation in 44% of animals compared with 0% in all other groups. Minute ventilation and the hypercapnic ventilatory response were significantly reduced in the postinjury period in the TBI/HS/EtOH group. The animals in this group had significantly lower CPP and cardiac output in the first 60 minutes postinjury, as well as lower renal and cerebral blood flow. Postinjury cerebral venous lactate levels were higher, and cerebral venous pH was lower in the TBI/HS/EtOH group. CONCLUSIONS: In this model of TBI, acute EtOH intoxication in the presence of HS potentiates the physiological and metabolic alterations that may contribute to secondary brain injury.

[Teleconsultation network for ophthalmology--experiences and results]. / Telekonsultationsnetzwerk für die Ophthalmologie--Erfahrungen und Ergebnisse.

MOTIVATION: Telemedical services for ophthalmology are developed within the OPHTEL project, which has been funded by the European Union and by the Bavarian government in the Bavaria-online initiative. METHODS: Seven private ophthalmologists, one university eye clinic, one clinical Diabetes center and an informatics research institute are connected within a teleconsultation network. Asynchronous (based on Internet E-Mail) and synchronous (based on ISDN-mediated videoconferencing tools) types of teleconsultations are realized. RESULTS: 86 teleconsultations (62 asynchronous, 23 synchronous) took place within the first 10 months. Complex and rare eye diseases as well as interdisciplinary questions (ophthalmology--diabetology) are the main area of medical communication interest. Legal and security problems are discussed. CONCLUSIONS: Telemedical services must be understood as a complete process of medical care on the basis of modern communication technologies, which influences also the management of this process.

[Scientific role of German ophthalmology in the European telecommunication project OPHTEL]. / Wissenschaftliche Rolle der deutschen Ophthalmologie im europäischen Telekommunikationsprojekt OPHTEL.

BACKGROUND: In Denmark, France, Germany, Great Britain and Italy, the OPHTEL project combines clinical centers of ophthalmology and internal medicine, an institute for medical informatics and health services research, a publishing company and different industrial partners in the EDP market. AIMS: With the aid of visual telecommunication and rapid data transfer, methods and conditions will be developed and proved so that any physician can very easily obtain sufficient information for treating his patient. Thus, the regional differences in the quality of structured health service (e.g., urban/ rural) will be overcome throughout Europe. SCIENTIFIC TASKS: A multilingual diagnostic and therapeutic thesaurus has to be worked out in order to create standards for communication and quality control. Based on literature, images and image analysis in a knowledge-based data bank, a monitoring system (containing watch-dog functions) and the basic aspects of an ophthalmological patient/disease register will be investigated. (In parallel, a technical development of synchronous and asynchronous telecommunication between eye physicians is taking place in close cooperation with the regional Bavarian project Teleopathalmology in Bavaria on-line). RESULTS: State of the art 6 months after starting the project:the knowledge-based image data bank has been founded and also an ophthalmological 8 language thesaurus and definition standard. All data transfer lines are installed. DISCUSSION: The project is taking place amid diverging sections of medicine: ophthalmology and internal medicine, health politics and data protection, individual treatment and common interest (health care), product management and office organization. Thus, the scientific quality of the transferred ophthalmological content must undergo sophisticated controls. FUTURE STEPS: Intense cooperation with the big German associations for ophthalmology (DOG, BVA) and the European ophthalmological societies concerning EDP, classification and quality control.

[Development and organization of a knowledge-based documentation system for ophthalmologic video documentation]. / Entwurf und Realisierung eines wissensbasierten Dokumentationssystems für ophthalmologische Videodokumentation.

We introduce a system for documentation of ophthalmological video tapes. This system can be implemented without regarding the German data security law (Bundesdatenschutzgesetz), because the documentation of the patient identification and the video tape identification number is done manually and separated from the EDP-supported documentation of the video tape identification number and the contents of the tape. But the use of a controlled vocabulary framework for diagnosis and surgery can be considered as the main advantage of this system. This enables a complete and fast retrieval to all records containing the terms searched for. Our system provides additional space for non-standardized text-documentation, e.g. comments etc... The implemented search-editor allows a fast retrieval to all records by input of strings, which can be connected by boolean expressions.

[A new laser scan system for video ophthalmoscopy. Initial clinical experiences also in relation to digital image processing]. / Ein neues Laser-Scan-System für die Fernseh-Ophthalmoskopie. Erste klinische Erfahrungen auch in Verbindung mit der digitalen Bildverarbeitung.

The clinical advantages of a scanning laser ophthalmoscope (SLO) and video imaging of fundus pictures are described. Image quality (contrast, depth of field) and imaging possibilities (confocal stop) are assessed. Imaging with different lasers (argon, He-Ne) and changes in imaging rendered possible by confocal alignment of the imaging optics are discussed. Hard copies from video images are still of inferior quality compared to fundus photographs. Methods of direct processing and retrieval of digitally stored SLO video fundus images are illustrated by examples. Modifications for a definitive laser scanning system - in regard to the field of view and the quality of hard copies - are proposed.