BACKGROUND:To investigate the feasibility and efficacy of earlier induction of hypothermia already during the 'no-flow' period of cardiac arrest with non-invasive surface cooling or invasive aortic flush cooling.METHODS:This was a prospective randomized experimental study that included 14 pigs, Large White breed (30-38 kg), with ventricular fibrillation cardiac arrest plus blanket surface and an invasive cold saline flush cooling. The endpoint was a decline in brain temperature (T(br)) at 35 min after cardiac arrest.RESULTS:With surface cooling, T(br) decreased from 38.7+/-0.2 degrees C to 37.4+/-0.8 degrees C (P=0.02) and with invasive cooling T(br) decreased from 38.8+/-0.13 degrees C to 19.0+/-2.8 degrees C within 216+/-23 s (P=0.02) and increased back to 33.0+/-0.6 degrees C at 35 min of cardiac arrest (P=0.02 vs. T(br) at 15 min, P=0.002 vs. T(br) at 35 min in the surface cooling groups).CONCLUSION:Invasive cooling by aortic flush with cold saline rapidly induces deep cerebral hypothermia, whereas non-invasive surface cooling only marginally decreases brain temperature.

The aim of this prospective, randomized, experimental study was to develop a novel, highly observer-independent, neurologic examination procedure for a standardized evaluation of outcome in intensive care models of cardiac arrest in pigs. Anaesthetized Large White pigs (n = 22) weighing 27-37 kg were put into ventricular fibrillation cardiac arrest for various times of no-flow (0-15 min) followed by various times of low-flow (8-20 min) by chest compressions, ventilation, and vasopressors. After successful defibrillation, controlled ventilation was continued for 24 hrs, and intensive care for 72 hrs. Some animals were treated with mild hypothermia for 24 hours. At 24, 48, and 72 hrs, neurologic outcome of each pig was evaluated by 2 blinded investigators (with one repetition at each time point) by means of a newly designed neurologic deficit score (NDS) and overall performance category (OPC) classification scheme. The largest contribution to the total variability in the NDS as well as OPC was due to the different treatments (e.g. duration of cardiac arrest, hypothermia) and the time points of evaluation (i.e. 24, 48, and 72 hrs after resuscitation). There was only a marginal disagreement between investigators, and practically no variability between repetitions at each time point. Within the NDS, the evaluation of mental state and breathing pattern showed less corresponding results when compared to the evaluation of cranial nerve reflexes and peripheral motor as well as sensory functions. In addition, NDS correlated well with OPC. The neurologic examination procedure proved to be a reliable and highly observer-independent tool for the evaluation of the functional neurologic status in pigs resuscitated from cardiac arrest.

Introduction: We have shown previously that induction of deep cerebral hypothermia with ice-cold saline aortic flush during cardiac arrest (CA) just before resuscitation (i.e. EPR) improved neurological outcome in pigs. To avoid fluid overload we developed a cardiopulmonary bypass cooling system (CPBCS) for rapid induction of hypothermia. We hypothesised that different levels of hypothermia during cardiac arrest will affect neurological outcome after prolonged normovolemic CA in pigs.

Introduction: Rapid induction of therapeutic hypothermia might further improve neurological outcome after cardiac arrest. The preliminary safety and effectiveness of the RhinoChill device (BeneChill, Inc., San Diego, CA) was assessed in survivors of cardiac arrest.

Background In former studies we have shown that induction of deep cerebral hypothermia via ice cold saline aortic flush already during cardiac arrest (CA) no-flow to mitigate reperfusion injury (e....

s* * Alphabetisch nach Erstautor gereiht Novel simple and non-invasive surface cooling method for rapid induction of mild hypothermia in adult human-sized pigs K. Bayegan1, A. Janata1, W. Weihs1, A. Schratter1, R. Faworka3, M. Frossard1, M. Holzer1, F. Sterz1, U. Losert2, A. N. Laggner1, and W. Behringer1 1 Department of Emergency Medicine, 2 Core Center of Biomedical Research, Medical University of Vienna, Austria 3 Emcools – Emergency Medical Cooling Systems AG Purpose of the study: Neuroprotective effects of mild therapeutic hypothermia have recently been reported in several studies. Rapid and early induction is found to be crucial for best results. An array of cooling devices has since been under extensive exploration. The aim of the study was to investigate feasibility and safety of a new cooling device. Materials and methods: Six pigs (64–89 kg) were anaesthetized and mechanically ventilated. Brain temperature (Tbr) was measured in the parietal lobes, and core temperatures in the pulmonary artery (Tpa) and urinary bladder (Tbl). Pigs were cooled to 33.5 °C during spontaneous circulation with the external cooling device, consisting of multiple pre-cooled (–10 °C) metallic plates in different sizes attached to the skin (prototype by EMCOOLS, Vienna). Then, after re-warming and induction of cardiac arrest, pigs were cooled during no-flow. Results: During spontaneous circulation, external cooling decreased Tbr from 38.0 °C to 33.5 °C within 30 ± 5 minutes. Mean cooling rate was 9.3 ± 1.4°C/h. During the one hour observation period, lowest Tbr, Tpa, and Tbl were 32.5 ± 0.2 °C, 32.5 ± 0.3 °C, and 33.2 ± 1.0 °C, respectively. During cooling, heart rate decreased from 89 bpm (IQR 76–108) to 70 bpm (IQR 64–81) (p = 0.05), and mean arterial pressure decreased from 71 mmHg (IQR 65–82) to 53 mmHg (IQR 49–59) (p = 0.03). During no-flow, Tbr did not reach 33.5 °C in all pigs. Mean cooling rate was 4.1 ± 1.6 °C/h. During the one hour observation period, lowest Tbr, Tpa, and Tbl were 34 ± 1.6 °C, 36 ± 1.9 °C, and 37.7 ± 0.3 °C, respectively. No skin lesions were observed during either cooling phase. Conclusion: This novel external cooling device, independent of an energy source during cooling, proved feasible and safe for rapid induction of mild therapeutic hypothermia in human-sized pigs. Further investigation of this method is needed to evaluate its efficacy in the clinical setting, especially in the emergency setting, where simplicity and immediate availability are fundamental. Left ventricular pseudoaneurysm W. Dichtl1, J. Bonatti2, O. Pachinger1, and T. Bartel1 1 Clinical Department of Cardiology, 2 Clinical Department of Cardiac Surgery, Medical University Innsbruck, Austria Background: While free wall rupture occurs in up to 8% of patients with myocardial infarction and is responsible for nearly 20% of all infarction-related deaths, formation of a pseudoaneurysm is a rare event. Pseudoaneurysm develops in the softened necrotic area where hematoma, thrombus and pericardium originally sealed an incomplete rupture of the left ventricle. This condition has to be distinguished from a true aneurysm which has a wide base and contains myocardial elements in its wall. Case report: A 59-year old woman with diabetes mellitus type II presented with subacute myocardial infarction in a rural hospital. After two days of conservative treatment, she developed cardiogenic shock within few hours, and the patient was transfered to our department. Transthoracic echocardiography showed new onset pseudoaneurysma of the left ventricle, communicating through a narrow base of the anterolateral wall. Emergency operation with successful resection of the pseudoaneurysma was performed. Despite a prolonged postoperative stay in the intensive care unit complicated by wound infections and critical illness polyneuropathy, the patient finally recovered. Conclusions: As in this case, prompt echocardiographic diagnosis is essential, as pseudoaneurysms have a high risk of free rupture, leading to hemopericardium and in most cases death from cardiac tamponade. Patients can be salvaged only by emergency surgical repair. Ein gefährlicher und kostspieliger Zwischenfall im MR. Fallbericht und Literaturübersicht P. Eisenburger1, A. Herneth2, A. N. Laggner1 und H. Imhof 1 Universitätsklinik für Notfallmedizin, 2 Universitätsklinik für Radiodiagnostik, Medizinische Universität Wien, Wien, Österreich Eine Patientin wurde zur Diagnostik eines akuten ischämischen Insultes in den Magnetresonanztomographen gebracht. Es wurden alle metallischen Gegenstände von Personal und Patientin entfernt. Da die Patientin (85 kg) unruhig war, wurde sie mit 20 mg Propofol sediert. Für das Einfahren in den Untersuchungsraum wurde der Monitor diskonnektiert, die Sauerstoffflasche blieb im Steuerungsraum. Da die Patientin im Untersuchungsraum vor dem Umlagern zyanotisch wurde, wurde die wenige Meter entfernte Sauerstoffflasche vom begleitenden Notfallmediziner in einer Reflexhandlung in den Untersuchungsraum geholt. Sie wurde von einer Distanz von etwa 2–3 Meter vom 1.5 Tesla MRScanner angezogen und samt Rollwagen in die Röhre gehoben. Es kam zu keinem Personenschaden, aber der materielle Schaden (> 100.000,– €) machte eine Reparatur unrentabel, weshalb eine Neuanschaffung vorgezogen werden musste. In der Literatur finden sich nur wenige Fallberichte mit metallischen Objekten in MR-Scannern. Eine Serie beschreibt 5 Zwischenfälle; die amerikanische FDA listet nur Beispiele, aber keine Gesamtzahlen auf. Allerdings wurde bei einer Umfrage erhoben, dass in 52% aller in MR-Anlagen ein grober Zwischenfall stattgefunden hat. Sauersstoffflaschen sind dabei die häufigsten Projektile, andere sind Scheren, Infusionsständer, Defibrillatoren, Sandsäcke etc. Im Jahr 2001 gab es einen tödlichen Unfall, bei dem eine Sauerstoffflasche einen 6-jährigen Buben tötete. Auch ein Feuerwehrmann wurde beim Ein-

Aim The presence of a transcapillary arterial-interstitial gradient for glucose (AIG(glu)) in skeletal muscle may be interpreted as a consequence of intact cellular glucose uptake. We hypothesized that the AIG(glu) decreases in Type 2 diabetes mellitus as a consequence of insulin resistance, whereas it remains intact in Type 1 diabetes.Methods Glucose concentrations were measured in serum and interstitial space fluid of skeletal muscle during an oral glucose tolerance test (OGTT) in patients with Type 1 and Type 2 diabetes and in young and middle-aged healthy volunteers, using microdialysis.Results The area under the curve for glucose in serum (AUC(SE)) was higher than in interstitial space fluid of skeletal muscle (AUC(MU)) in healthy young (AUC(SE)=1147+/-332 vs. AUC(MU)=633+/-257 mM/min/ml; P=0.006), healthy middle-aged volunteers (AUC(SE)=1406+/-186 vs. AUC(MU)=1048+/-229 mM/min/ml; P=0.001) and in Type 1 diabetic patients (AUC(SE)=2273+/-486 vs. AUC(MU)=1655+/-178 mM/min/ml; P=0.003). In contrast, in Type 2 diabetic patients AUC(SE) (2908+/-1023 mM/min/ml) was not significantly different from AUC(MU) (2610+/-722 mM/min/ml; P=NS).Conclusions The present data indicate that AIG(glu) is compromised in Type 2 diabetes in contrast to Type 1 diabetes where it appears to be normal. Because no changes in muscle blood flow were detected, insulin resistance appears to be the main cause for the observed decreased AIG(glu) in skeletal muscle in Type 2 diabetic patients.

Objective: Induction of deep cerebral hypothermia before reperfusion might improve neurologic outcome after cardiac arrest. We hypothesized that an aortic flush with cold saline during cardiac arrest is able to induce deep cerebral hypothermia and that the cooling efficiency can be enhanced by a) increasing the arteriovenous pressure gradient during the flush with vasopressin; b) improving the cerebral microcirculation during the flush with the thrombolytic agent alteplase; and c) increasing the arteriovenous pressure gradient further with venting the right heart by draining blood during the flush.Design: Prospective randomized experimental study.Setting: University research laboratory.Subjects: Twenty-four pigs Large White breed (31-42 kg).Interventions: After 10 mins of ventricular fibrillation, pigs received an aortic flush (100 mL/kg, 4 degrees C, flow rate 35 mL/kg/min) into the descending aorta via a balloon catheter. The animals were subjected randomly to either an aortic flush with saline, saline plus vasopressin 1.2 IU/kg, saline plus alteplase 1 mg/kg, saline plus a combination of vasopressin 1.2 IU/kg and alteplase 1 mg/kg, or saline plus vasopressin 1.2 IU/kg and venting the right heart. Arterial and venous pressures and brain temperatures were recorded for an observation time of 10 mins after flush.Measurements and Main Results: A sufficient arteriovenous pressure gradient and deep cerebral hypothermia were only achieved with a flush containing vasopressin (brain temperature 16.1 +/- 1.3 degrees C in the vasopressin group vs. 35.4 +/- 1.5 degrees C in the saline group, p < .001); combining vasopressin with alteplase, or venting the right heart, did not further enhance the cooling efficiency of the flush.Conclusions: A cold saline aortic flush with vasopressin rapidly decreases brain temperature during prolonged normovolemic cardiac arrest in pigs. Whether deep cerebral hypothermia induced before reperfusion can improve neurologic outcome after cardiac arrest needs further investigation in large animal outcome studies.

C. pneumoniae does not play a clinically relevant role in acute and chronic aortic disease. The impact of other organisms of the family Chlamydiaceae needs further evaluation.

Background: Intra-aortic balloon pump (IABP) counterpulsation in cardiogenic shock (CS) is suggested as bridging therapy to definite emergency revascularization, heart transplantation and acute valvular repair. Data concerning the use of IABP counterpulsation in an emergency department (ED) are rare. Patients and Methods: We reviewed retrospectively the charts of patients who had been treated by IABP counterpulsation in the ED of a tertiary care university hospital during a 7-year period. We analyzed indications for IABP treatment, complications of IABP use and studied various predictors for 30-day survival. Results: Overall 88 (68 male) patients, median age 60 years (IQR 53-69 years) were treated with IABP counterpulsation. CS was caused by acute coronary syndrome (ACS), acute cardiomyopathy decompensation of (CMP) and aortic stenosis (AS) in 77 (87%), ten (12%) and one (1%) patients, respectively. Complications attributed to the insertion or maintenance of IABP were observed in nine (10%) patients. Thirty four patients (38%; 24 male) survived. Compared to non-survivors, these patients were younger (56 vs. 63 years; P < 0.023) and had significant lower serum lactate levels before IABP insertion (3 vs. 5.5 mmol/l; P < 0.002). Logistic regression analysis identified age (P < 0.04) and serum lactate serum level before IABP (P < 0.01) as independent predictors for survival. In the 77 patients with ACS PTCA tended to be associated with a higher rate of survival (P < 0.09). Conclusion: Initiation of IABP counterpulsation in patients with CS in an ED appears safe. Low levels of serum lactate and younger age were independent predictors of survival. In patients with ACS PTCA may contribute to improved outcome. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.

BACKGROUND Chlamydia species are suspected of being involved in the pathogenesis and progression of aortic aneurysms. We investigated serum levels of Chlamydia antibodies in patients with thoracic aortic aneurysms (TAA) and abdominal aortic aneurysms (AAA) compared to levels in healthy individuals. METHODS We included 35 consecutive patients with TAA, 42 patients with AAA and 42 age- and sex-matched healthy controls in a case control study. Serum antibodies (IgM and IgG) against Chlamydia lipopolysaccharide (LPS), Chlamydia pneumoniae and Chlamydia trachomatis were measured by recombinant ELISA and quantified by measurement of optical density. RESULTS Patients with TAA exhibited median immunoglobulin levels against Chlamydia LPS (IgM 0.090, IgG 0.266), C. pneumoniae (IgM 0.023, IgG 0.264) and C. trachomatis (IgG 0.247) comparable to those of healthy subjects [Chlamydia LPS IgM 0.209 (p = 0.1), IgG 0.301 (p = 0.2); C. pneumoniae IgM 0.051 (p = 0.07), IgG 0.516 (p = 0.1); C. trachomatis IgG 0.153 (p = 0.2)]. Patients with AAA had higher serum levels of IgG against Chlamydia LPS (0.560) compared to healthy individuals [0.301 (p = 0.04)], but no significant elevation of antibodies against C. pneumoniae [IgM 0.029 (p = 0.1), IgG 0.545 (p = 0.9)] and C. trachomatis [IgG 0.219 (p = 0.3)]. CONCLUSION Thoracic aortic aneurysms were not associated with signs of Chlamydia infection or immunopathogenicity. In contrast, patients with abdominal aortic aneurysms exhibited elevated levels of immunoglobulin against Chlamydia LPS, reflecting an unspecific Chlamydia immunopathogenicity. However, elevated levels of antibodies against distinct Chlamydia species were also not found in AAA patients.

Objective: Lipoprotein (a) is an independent risk factor for atherosclerosis. Atherosclerotic degeneration is usually found in abdominal aortic aneurysms (AAAs), whereas thoracic aortic aneurysms (TAAs) caused by aortic dissection are not suggested to be linked pathogenetically to atherosclerosis. Lipoprotein (a) was analyzed in patients with AAA and TAA and in healthy individuals in relation to the extent of atherosclerosis.Methods. Included in the case control study were patients with AAA (n = 75) and TAA with dissection (n = 39) and healthy control subjects (n = 43), for a total of 157 participants. Serum lipoprotein (a) was measured with nephelometry. Lipoprotein (a) levels were compared between age-matched and gender-matched paired samples of the three groups, and an association of lipoprotein (a), aortic aneurysm, and the extent of atherosclerosis was determined in multivariate analysis.Results. Median lipoprotein (a) levels of patients with AAA and TAA and of control subjects were 18.9 mg/dL (interquartile range [IQR] <9.6 to 40.5), less than 9.6 mg/dL (IQR <9.6 to 16.7), and less than 9.6 mg/dL (IQR, <9.6 to 16.3), respectively. Lipoprotein (a) was positively associated with the extent of atherosclerosis in patients and control subjects (P <.0001). Lipoprotein (a) levels of patients with AAA were significantly higher compared with patients with TAA (P <.0001) and control subjects (P <.0001). Multivariate analysis confirmed an independent association between lipoprotein (a) and AAA (P =.009). No significant differences of lipoprotein (a) were found between patients with TAA and control subjects (P =.3).Conclusion: The lipoprotein (a) serum level, an indicator of atherosclerosis, is significantly elevated in patients with abdominal aneurysms independently of cardiovascular risk factors and the extent of atherosclerosis. Patients with TAAs caused by dissection have lipoprotein (a) levels comparable with healthy individuals.

Background: There is increasing evidence that an inflammatory process is present in abdominal aortic aneurysms (AAAs) to varying degrees. The aim of this study was to compare acute phase reactants in patients with asymptomatic AAA, symptomatic AAA without rupture and ruptured AAA. Method: Two hundred and twenty-five consecutive patients treated because of AAA were included in this case-control study. Polynomial logistic regression analysis was applied to compare admission C-reactive protein (CRP) and white blood count (WBC) measured in I I I asymptomatic outpatients, 52 symptomatic patients without rupture and 62 patients with rupture of the aneurysm. We adjusted for the potentially confounding effect of age, sex, haemoglobin levels and aneurysm diameter. Results: Patients with symptomatic AAA and patients with ruptured AAA had significantly elevated CRP (p = 0.002) and WBC (p < 0.0001) levels compared to asymptomatic patients. There was no statistically significant difference in CRP and WBC between patients with symptomatic AAA and ruptured AAA. Median CRP values of asymptomatic, symptomatic and ruptured AAA were < 0.5 (interquartile range (IQR) < 0.5-0.85), 1.1(IQR < 0.5-4.0) and 2.4 mg/dl (IQR 0.65-8.6), respectively, and median WBC values were 6.5 (IQR 5.5-8.0), 8.7 (IQR 6.8-11.2) and 13.2 (IQR 10.5-17.0), respectively. Conclusion: A significant elevation of CRP and WBC could be found in patients who presented with symptoms or rupture of an AAA. These indicators of inflammation were not observed in asymptomatic patients with AAA. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.

Objective: Acute type A aortic dissection requires emergency surgery and is associated with considerable mortality. The aim of the study was to evaluate whether occurrence of preoperative cardiac tamponade with or without palpable pulses, in these patients is associated with higher incidence of multiple organ failure (MOF) and in-hospital mortality. Methods: A retrospective cohort study included 87 patients with acute type A aortic dissection, who were admitted via an emergency department between December 1991 and December 1999 for emergency surgery. Impending cardiac tamponade (with palpable pulses) and severe cardiac tamponade (without palpable pulses) were recorded and patients were followed for occurrence of MOF and/or in-hospital mortality. Results: Impending cardiac tamponade with palpable pulses was diagnosed in 33 patients (38%), signs of severe cardiac tamponade without palpable pulses were found in seven patients (8%). MOF occurred in 41 patients (47%); 32 patients (37%) died during the present stay, all of them had MOR Preoperative severe cardiac tamponade without palpable pulses was associated with a significantly increased risk for poor outcome (odds ratio (OR) = 16.1, 70% confidence interval (CI) 4.8-71.7, P = 0.04), particularly preoperative death (n = 6 of 7). Impending cardiac tamponade with palpable pulses (OR = 1.6, 70% CI 0.8-3.3, P = 0.2) was not associated with the occurrence of MOF/death. Hemodynamic shock (OR = 6.5, 70% CI 3.0-13.9, P = 0.01) was also associated with poor outcome. Conclusion: Patients with acute type A aortic dissection and signs of preoperative cardiac tamponade without palpable pulses had a 16-fold increased risk for poor outcome, particularly preoperative death. In contrast, cardiac tamponade with palpable pulses was not associated with increased frequency of MOF/in-hospital mortality. (C) 2001 Elsevier Science BN. All rights reserved.