Potential of mid-infrared spectroscopy to aid the triage of patients with acute chest pain.

A total of 1,429 serum samples from 389 consecutive patients with acute chest pain were analyzed with the goal to aid the rapid diagnosis of acute myocardial infarction. To the best of our knowledge this is the largest and most comprehensive study on mid-infrared spectroscopy in cardiology. We were able to identify those signatures in the mid-infrared spectra of the samples, which were specific to either acute myocardial infarction or chest pain of other origin (angina pectoris, oesophagitis, etc). These characteristic spectral differences were used to distinguish between the cause of the donor's acute chest pain using robust linear discriminant analysis. A sensitivity of 88.5% and a specificity of 85.1% were achieved in a blind validation. The area under the receiver operating characteristics curve amounts to 0.921, which is comparable to the performance of routine cardiac laboratory markers within the same study population. The biochemical interpretation of the spectral signatures points towards an important role of carbohydrates and potentially glycation. Our studies indicate that the "Diagnostic Pattern Recognition (DPR)" method presented here has the potential to aid the diagnostic procedure as early as within the first 6 hours after the onset of chest pain.

Creatine kinase-mb fraction and cardiac troponin T to diagnose acute myocardial infarction after cardiopulmonary resuscitation.

OBJECTIVES: This study sought to evaluate the diagnostic value of the biochemical markers creatine kinase (CK), creatine kinase-MB fraction (CK-MB) and cardiac troponin T (cTNT) to diagnose acute myocardial infarction (AMI) after cardiopulmonary resuscitation (CPR). BACKGROUND: Elevations of CK and CK-MB after CPR are a frequent finding and might be associated with ischemic myocardial injury, as well as physical trauma to the chest. METHODS: Patients who had cardiac arrest and primary successful resuscitation were included in the study. The diagnosis of AMI was confirmed or ruled out by means of typical electrocardiographic findings, thallium-201 myocardial scintigraphy or autopsy, if death occurred during the hospital period, in 39 primary survivors of sudden cardiac death. In 24 patients (62%) the diagnosis of AMI was established. Serum cTNT, CK and CK-MB were measured, and the CK-MB/CK ratio was calculated on admission and after 12 h. RESULTS: On admission all markers of myocardial injury proved to be weak methods for the diagnosis of AMI. After 12 h cTNT as well as CK-MB exhibited a similar diagnostic performance; CK and the CK-MB/CK ratio proved to be worthless. Sensitivity and specificity for a cTNT cutoff value of 0.6 ng/ml, 12 h after cardiac arrest, were 96% and 80%, respectively. For a CK-MB cutoff value of 26 U/liter, sensitivity was 96% and specificity was 73%. CONCLUSIONS: Cardiac TNT and CK-MB are valuable tools in detecting AMI as the cause of sudden cardiac death. However, there is a considerable lack of sensitivity and specificity. Cardiac injury is probably caused not only by AMI, but also by myocardial damage related to CPR efforts.

Clinical evaluation of different doses of intravenous enalaprilat in patients with hypertensive crises.

BACKGROUND: The appropriate dose of intravenous enalaprilat to be used in the treatment of hypertensive crisis is controversial. There has been no comparative study of the efficacy and safety of different dosages of enalaprilat in hypertensive patients. METHODS: Sixty-five consecutive patients with hypertensive urgencies (systolic blood pressure > 210 mm Hg and/or diastolic blood pressure > 110 mm Hg) or emergencies (diastolic blood pressure > 100 mm Hg and evidence of end-organ damage, ie, angina pectoris, hypertensive encephalopathy, or congestive heart failure) admitted to an emergency department from January 1, 1994, to September 30, 1994, were identified. The patients were randomized to receive different doses of enalaprilat (0.625, 1.25, 2.5, and 5 mg). Response to treatment was defined as a stable reduction of systolic blood pressure to below 180 mm Hg and diastolic blood pressure to below 95 mm Hg within 45 minutes after the start of treatment and relief of symptoms in patients with hypertensive emergencies. RESULTS: In 41 (63%) of 65 patients, the treatment goal was reached. Twenty-four patients (37%) failed to achieve the goal of treatment within 45 minutes after administration of enalaprilat. The response rates in the 0.625-mg, 1.25-mg, 2.5-mg, and 5-mg groups were 67%, 65%, 59%, and 62%, respectively. The proportion of patients initially randomized who responded to treatment was not different between any of the four groups of enalaprilat doses. There were no significant differences according to enalaprilat dose with respect to changes in systolic, diastolic, and mean arterial blood pressure. No severe side effects were observed. CONCLUSION: Enalaprilat is a safe antihypertensive drug with moderate efficacy in the treatment of hypertensive crisis. As doses above 0.625 mg alter neither response rates nor the magnitude of blood pressure reduction, we recommend 0.625 mg as the initial dose in the treatment of hypertensive crisis.

Course of blood pressure within the first 12 h of hypertensive urgencies.

OBJECTIVE: To evaluate the course of blood pressure within 12 h of a hypertensive urgency with or without oral antihypertensive treatment prior to discharge of patients from hospital. DESIGN: A prospective, double-blinded, placebo-controlled and randomized clinical trial. SETTING: Department of Emergency Medicine in a 2000-bed inner city hospital. PATIENTS: Forty patients successfully treated for a hypertensive urgency with intravenous administration of urapidil. INTERVENTIONS: We administered 60 mg urapidil orally or placebo prior to discharge of patients from hospital and evaluated the course of blood pressure within 12 h of the urgency by use of an ambulatory blood pressure measurement unit. MAIN OUTCOME MEASURES: Mean systolic and diastolic blood pressures within the first 12 h of a hypertensive urgency and the number of hypertensive and hypotensive episodes. RESULTS: Mean systolic and diastolic blood pressures were significantly lower in members of the urapidil group than they were in members of the placebo group (132 +/- 14 versus 147 +/- 18 mmHg, P = 0.003; 79 +/- 12 versus 87 +/- 14 mmHg, P = 0.047, respectively). The number of hypotensive episodes was similar for these two groups (three versus one, P = 0.32), whereas the number of hypertensive episodes was significantly lower for the urapidil group (13 versus 34, P = 0.001). CONCLUSIONS: Oral medication with urapidil prior to discharge results in lower overall blood pressure levels and reduces the risk of hypertensive episodes recurring within 12 h of a hypertensive urgency. Therefore, we recommend this therapeutic approach for patients with hypertensive urgencies, who are treated with an intravenous antihypertensive drug.

Use of an age-adjusted Doppler E/A ratio in patients with moderate to severe hypertension.

OBJECTIVE: To assess the ratio of early (E) to late atrial (A) mitral Doppler peak flow velocity (Doppler E/A ratio) before and after adjustment for age in patients with moderate to severe hypertension, in whom left ventricular diastolic dysfunction is an early finding. Mitral flow patterns can be used to assess diastolic filling characteristics, and the Doppler E/A ratio is the parameter most commonly used, although it is known to be strongly age dependent. There are no established normal values for this ratio. DESIGN: Retrospective data analysis. SETTING: A 2000-bed tertiary-care teaching hospital. PATIENTS: We studied 190 patients (99 women and 91 men; ages 55 +/- 13 years) with moderate to severe hypertension. INTERVENTIONS: The ratio of early (E) to late atrial (A) mitral Doppler peak flow velocity was measured. As this ratio depends on age, a Z score was calculated to control for this influence. The Z score is the standardized normal deviation of the mean, with a normal value of 0 +/- 2. MAIN OUTCOME MEASURES: Sensitivities and specificities for detecting an age-dependent reduction in Doppler E/A score (Z score less than -2) with a non-age-dependent Doppler E/A ratio (less than 1) were calculated. RESULTS: In 106 of the patients (56%) the Doppler E/A ratio was less than 1.0. Only nine patients (4.7%) had a Z score less than -2. The sensitivity of the Doppler E/A ratio threshold of 1.0 for detecting a Z score less than -2 was 0.89 and the specificity was 0.46. A Z score less than -2 was found only in patients younger than 45 years. CONCLUSIONS: The Doppler E/A ratio was reduced in a large proportion of our patients. However, after correction for age it was decreased in only 4.7% of these patients. The use of a single Doppler E/A ratio threshold value has a weak diagnostic power to detect age-independent changes in mitral flow patterns.

Increased blood pressure response to the cold pressor test in pregnant women developing pre-eclampsia.

OBJECTIVES: Recent data indicate an increased vascular reactivity due to an overactivity of the sympathetic nervous system in women with pre-eclampsia. We therefore evaluated whether this increased vascular reactivity can be detected prior to the clinical manifestation of preeclampsia by the use of a physiological stimulus. DESIGN: Prospective data collection. SETTING: Clinic of Obstetrics and Gynecology in a 2000 bed tertiary care hospital. PARTICIPANTS: One hundred and twenty-three pregnant women between the 16th to 20th week of gestation. INTERVENTIONS: A cold pressor test was performed by positioning an ice-bag on the forehead of the woman for 3 min. Blood pressure and heart rate were monitored by a continuous, noninvasive blood pressure measurement device during the stimulus and after removal of the icebag. A clinical follow-up was carried out by review of the charts after delivery to identify those women who have developed pre-eclampsia. RESULTS: Ten (8%) out of 123 pregnant women developed pre-eclampsia. During the cold pressor test systolic as well as diastolic blood pressure increased significantly and was more pronounced in women developing pre-eclampsia compared with healthy pregnant women (systolic blood pressure: 14.2 +/- 5.5 versus 8.5 +/- 7.2 mmHg, P= 0.02; diastolic blood pressure: 7.3 +/- 4.9 versus 3.9 +/- 4.7 mmHg, P=0.03). The change in heart rate was similar between both groups (8 +/- 2.6 versus 10.4 +/- 6.4 beats/min, not significant). CONCLUSIONS: An increased vasoconstrictive response to a physiological stimulus is present in women with pre-eclampsia as a sign of an increased vascular reactivity prior to clinical manifestation of the disease. The cold pressor test may be a suitable diagnostic tool to identify women, who will develop pre-eclampsia. However, future studies in larger cohorts are required to establish the final value of this test.

Attenuation of thrombolysis-induced increase of plasminogen activator inhibitor-1 by intravenous enalaprilat.

We examined the effect of intravenous enalaprilat on the course of PAI-1 plasma levels in 23 patients with acute myocardial infarction undergoing thrombolytic therapy. All patients received 100 mg aspirin, 1000 IU/h heparin, thrombolysis with 100 mg rt-PA within 90 min, and betablockers. Eleven out of 23 patients received 5 mg enalaprilat intravenously prior to thrombolysis. Blood samples for determination of PAI-1 plasma levels were collected on admission, 2, 4, 6, 12, and 24 h after thrombolysis. PAI-1 plasma levels in patients receiving enalaprilat were similar to those of the control patients before thrombolysis (5 ng/ml, 95% confidence interval: 2-10 vs. 7 ng/ml, 95% confidence interval: 2-10; p = 0.5). The PAI-1AUC was 9 ng/ml/h (95% confidence interval: 5-10) in the enalaprilat group and 19 ng/ml/h (95% confidence interval: 13-26) in the control group (p = 0.0006). The maximum difference was observed 6 h after thrombolysis (enalaprilat: 13 ng/ml, 95% confidence interval: 5-25, control: 42 ng/ml, 95% confidence interval: 18-55; p = 0.003). Our study clearly demonstrates that application of intravenous enalaprilat prior to thrombolysis attenuates the thrombolysis-related increase of PAI-1. This finding may suggest a possible therapeutic approach to influence the fibrinolytic system in patients with acute myocardial infarction after thrombolysis.

Creatine kinase and creatine kinase-MB release after nontraumatic cardiac arrest.

The aim of the study was to describe the course of serum creatine kinase (CK) and its MB fraction (CK-MB) in patients surviving cardiac arrest, and to identify factors influencing CK and CK-MB release. The study was set in the community of Vienna, Austria. Data concerning cardiopulmonary resuscitation, collected within a period of 33 months, were evaluated retrospectively and compared with laboratory blood investigations collected prospectively (on admission and after 6, 12, and 24 hours) in 107 adult patients surviving a witnessed cardiac arrest for 24 hours. CK and CK-MB were elevated in >75% of the patients within 24 hours. Release of CK and CK-MB was mainly associated with electrocardiographic evidence of acute myocardial infarction (AMI) cumulative energy administered during defibrillation, and duration of chest trauma by compression. The CK-MB/CK ratio was elevated in 32% of the patients. Of patients with electrocardiographic evidence of AMI, only 49% had an elevated CK-MB/CK ratio. In conclusion, the elevation in serum CK and CK-MB fraction in patients after nontraumatic cardiac arrest is a frequent finding, and is associated with ischemic myocardial injury, as well as physical trauma to the chest. This should be considered when interpreting the course of CK and CK-MB fraction for the diagnosis of AMI.

Guidelines for the drug treatment of hypertensive crises.

Hypertensive crises are a group of clinicopathological entities in which rapid reduction of hypertension is necessary to prevent serious end-organ damage. The diagnosis and treatment plan depends on the identification of specific end-organ dysfunction. The goal of treatment is to limit the progression of end-organ damage in patients with hypertensive crises. Several potent antihypertensive drugs, such as sodium nitroprusside, labetalol and urapidil, are available to produce an immediate fall in blood pressure. The choice of the drug should be made on the basis of its pharmacodynamic properties, clinical effects, advantages and contraindications. Additionally, rapid reduction of blood pressure carries a considerable risk, if it is performed in an uncontrolled manner, leading to further end-organ damage. The aim of the treatment is not just to reduce blood pressure, but to do so with minimal adverse effects while preserving organ function.

Inducible atrial flutter and fibrillation after orthotopic heart transplantation.

Inducible atrial flutter (two patients) and fibrillation (two patients) were observed in a series of 35 heart transplant patients who underwent evaluation of sinus node function including premature atrial stimulation. The sinus node function was entirely normal in both patients with inducible atrial flutter. In contrast it was profoundly abnormal in the patients with inducible atrial fibrillation. Atrial fibrillation was no longer inducible as the sinus node function became borderline normal. These observations suggest extensive electrical atrial abnormality, including the sinus node, in patients with atrial fibrillation, and temporary pacing should be available when considering cardioversion in patients with atrial fibrillation early after heart transplantation. Atrial flutter, in contrast, may be inducible in the absence of any sinus node abnormality and without any evidence of rejection.

Safety and efficacy of urapidil and sodium nitroprusside in the treatment of hypertensive emergencies.

OBJECTIVE: To assess the safety and efficacy of urapidil compared to sodium nitroprusside in the treatment of hypertensive emergencies. DESIGN: Randomized, prospective clinical study. SETTING: Emergency department in a 2000-bed inner city hospital. PATIENTS: Eighty-one patients with hypertensive emergencies defined as elevation of systolic blood pressure above 200 mmHg and/or diastolic blood pressure above 110 mmHg plus evidence of end-organ damage were included in the study protocol. The efficacy of therapy was defined as 1) blood pressure reduction below 180/95 mmHg within 90 min and 2) no re-elevation of blood pressure during a 4-h follow-up period in primary responders. The safety of both drugs was defined as the number of minor and major side effects during treatment. INTERVENTIONS: Patients received either sodium nitroprusside (n = 35; continuous intravenous administration with a starting dose of 0.5 microgram/kg per min; increase in increments of 0.5 microgram/kg per min every 15 min until response to treatment or a maximum of 3 micrograms/kg per min) or urapidil (n = 46; intravenous bolus; starting dose: 12.5 mg; repetitive administration of 12.5 mg every 15 min until response or a maximum dose of 75 mg). MEASUREMENTS AND RESULTS: Blood pressure was measured every 2.5 min by using a non-invasive oscillometric blood pressure measurement unit. Response to treatment within 90 min was observed in 75 (93%) patients (urapidil: n = 41 [89%]; nitroprusside: n = 34 [97%]; p = 0.18). During the follow-up period 8/34 (24%) patients in the nitroprusside group and 1/41 (2%) patients in the urapidil group exhibited blood pressure re-elevation. Major side effects were observed in seven patients receiving nitroprusside and two patients in the urapidil group (p = 0.04). CONCLUSION: Urapidil is equally effective, compared to sodium nitroprusside, in the treatment of hypertensive emergencies. Due to a smaller number of adverse events, urapidil is a reasonable alternative to nitroprusside in the treatment of hypertensive emergencies.

The nitura study--effect of nitroglycerin or urapidil on hemodynamic, metabolic and respiratory parameters in hypertensive patients with pulmonary edema.

OBJECTIVE: To assess the effects of nitroglycerin or urapidil on hemodynamic, respiratory and metabolic parameters in hypertensive patients with pulmonary edema. DESIGN: Open, randomized and prospective clinical study. SETTING: Out-of-hospital setting and Emergency Department in a 2000-bed hospital. PATIENTS: Hundred twelve patients with evidence of hypertensive crises with pulmonary edema (systolic blood pressure (SBP) > 200 mmHg and/or diastolic blood pressure (DBP) > 100 mm Hg and rales over both lungs) at the time when the emergency physician arrived. INTERVENTIONS: The out-of-hospital treatment consisted of oxygen via face mask, 80 mg furosemide i.v., 10 mg morphium s.c., and either nitroglycerin sublingually (initial dose: 0.8 mg; repetitive administration of 0.8 mg every 10 min to a cumulative dose of 3.2 mg) or urapidil (initial dose: 12.5 mg i.v.; repetitive administration every 15 min to a cumulative dose of 50 mg). If SBP was more than 180 mm Hg and/or DBP more than 90 mm Hg on admission, antihypertensive treatment was continued with nitroglycerin (0.3-3 mg/h) or urapidil (5-50 mg/h). MEASUREMENTS AND RESULTS: Blood pressure (BP) was measured every 5 min with the use of an automatic oscillometric device. Serum lactate, PO2, pH value, and base excess (BE) were evaluated on admission and 6 h later. Blood pressure, serum lactate and BE on admission were significantly lower (SBP: 155 +/- 30 vs 179 +/- 33 mm Hg; p = 0.0002; DBP: 82 +/- 17 vs 93 +/- 19 mmHg; p = 0.001; lactate: 2.2 +/- 1.6 vs 3.9 +/- 2.7; p = 0.0001; BE: -1.9 +/- 3.9 vs -4.4 +/- 1.7; p = 0.0005) and PO2 and pH values were significantly higher in the urapidil group compared to the nitroglycerin group (PO2: 75 +/- 25 vs 66 +/- 17; p = 0.036; pH: 7.33 +/- 0.08 vs 7.29 +/- 0.09; p = 0.042). After 6 h no differences between the two groups were observed. CONCLUSION: The more pronounced BP reduction in the urapidil group was associated with an improved respiratory and metabolic situation in hypertensive patients with pulmonary edema. Therefore, urapidil is a valuable alternative to nitroglycerin in patients with pulmonary edema and systemic hypertension.

Out-of-hospital diagnosis of cerebral infarction versus intracranial hemorrhage.

OBJECTIVE: To establish a model based on clinical and anamnestic data easily available in the out-of-hospital setting, which facilitates the differential diagnosis between cerebral infarction and intracranial hemorrhage. DESIGN: Retrospective study that simulates a prospective approach. SETTING: Emergency Department of the University Hospital in Vienna, Austria. PATIENTS AND PARTICIPANTS: Data of 224 patients with either intracranial hemorrhage or cerebral infarction were prospectively collected. Uni-and multivariate analysis was performed to identify neurological symptoms and anamnestic data, which were associated with either intracranial hemorrhage or cerebral infarction. MEASUREMENTS AND RESULTS: Unilateral weakness or sensory loss was observed more frequently in patients with infarction compared to hemorrhage (69.8 % vs 11.9 %, P < 0.001). The frequency of patients with impaired level of consciousness was significantly higher in the hemorrhage group compared to the infarction group (59.3 % vs 3.8 %, P < 0.001). A multivariate logistic regression analysis showed that hypertension (OR = 0.31, 95 % CI = 0.12-0.76, P = 0.01), diabetes (OR = 0.17, 95% CI = 0.04-0.68, P = 0.01), and unilateral weakness or sensory loss (OR = 0.10, 95 % CI = 0.04-0.26, P < 0.001) were significantly associated with cerebral infarction. Impaired level of consciousness was significantly related to hemorrhage (OR = 13.41, 95 % CI = 3.92-45.91, P < 0.001). On the basis of the logistic regression analysis, we generated a scoring system for the out-of-hospital diagnosis between infarction and hemorrhage. The values of the score lay between -3 and +3. The probability of infarction increases when the score becomes negative, and the probability for hemorrhage increases when the score becomes positive. CONCLUSION: Our model is a useful guideline for the differential diagnosis between cerebral infarction and intracranial hemorrhage in the out-of-hospital setting, as it is based on easily available clinical and anamnestic parameters.

After antagonization of acute opiate overdose: a survey at hospitals in Vienna.

This study describes the clinical management and characteristics of people who, following acute opioid overdose, are taken to hospital after efficient antagonization by the pre-hospital emergency service. In addition, it defines areas of interest for further research. Over a 4-month period (September-December 1993) we collected data by a structured protocol sheet on patients' characteristics, anamnestic data on abuse and emergencies, clinical presentation, treatment by specific antidote and routine laboratory investigations. Outcome was verified by retrospective review of prehospital and forensic data. We studied 77 subjects, predominantly young males, who were involved in 83 emergencies, mostly occurring at weekends. In more than 60% of cases a single administration of specific antidote sufficed to stabilize the patients; 64% of patients left hospital against medical advice after an average stay of less than 6 hours; 46% denied daily opioid abuse and half the subjects, especially younger drug-users, seemed interested in counselling. This hospital-based study did not provide reliable data on the epidemiology of opioid overdose. Clinical management is determined by experience, pragmatism and beliefs. Efforts towards secondary prevention of drug problems at emergency departments might be warranted, and further research on pattern and management of opioid overdose is needed.

Recalibration of the point-of-care test for CARDIAC T Quantitative with Elecsys Troponin T 3rd generation.

The rapid troponin T assay CARDIAC T Quantitative was recalibrated using Elecsys Troponin T 3rd Generation as a new reference method. This paper presents the method comparisons at six centres using the new reference method. Method comparison between CARDIAC T Quantitative versus Elecsys Troponin T 3rd Generation were performed using 319 samples from patients with acute coronary syndromes. The quality of the CARDIAC T Quantitative was controlled by a daily single determination of CARDIAC Control Troponin T, and for the Elecsys Troponin T 3rd Generation, the Elecsys controls were included in each run. The results for the control materials for the CARDIAC T Quantitative were between 93% and 107% of the target values. The CV ranged from 7% to 16%. From the regression analysis, according to Bablok and Passing (y=1.07x) and the Bland and Altman plot, the bias between CARDIAC T Quantitative and Elecsys Troponin T 3rd Generation is from +6% to +7%. The correlation coefficient is 0.93, and a 3x3 comparison of the clinical efficiency yielded 92% clinical concordance between CARDIAC T Quantitative and Elecsys Troponin T 3rd Generation. In conclusion, CARDIAC T Quantitative was in good agreement with the reference and calibration method Elecsys Troponin T 3rd Generation.

Efficacy of different antihypertensive drugs in the emergency department.

Hypertensive crises are a commonly observed problem in an emergency department. The aim of the study was to evaluate the efficacy and safety of different antihypertensive agents in the treatment of patients with hypertensive crises. 168 patients (mean age: 52 +/- 12 years) admitted to the emergency department with a hypertensive urgency (systolic (SBP) blood pressure > 210 mm Hg and/or diastolic (DBP) blood pressure > 110 mm Hg) or a hypertensive emergency (DBP > 100 mm Hg and evidence of end-organ damage) were included into the study protocol. Blood pressure (BP) was measured every 5 min automatically using a noninvasive BP measurement unit. After a resting period of 30 min the patients received the following drugs: 5 mg enalaprilat intravenous (n = 43) or 25 mg urapidil intravenous (n = 48) or 10 mg nifedipine-capsule sublingual (n = 47) or 2 x 5 mg nifedipine-spray sublingual (n = 30). The aim of treatment was to reduce SBP below 180 mm Hg and DBP below 95 mm Hg within 45 min after start of treatment. When evaluating the response rates the highest rate was observed in the urapidil group (96%). The response rate of enalaprilat and both preparations of nifedipine were similar (70-72%). The rate of major side effects was higher in the urapidil compared to the other drugs (4% vs 2% in the nifedipine-group or 0% in the enalaprilat-group). All four drugs are suitable in the treatment of patients with hypertensive crisis in the emergency department. Urapidil should be used as a first choice drug in critically ill patients with hypertensive crisis due to its higher response rate.

Impact of the renin-angiotensin-aldosterone system on blood pressure response to intravenous enalaprilat in patients with hypertensive crises.

The purpose of the study was to evalute the impact of the renin-angiotensin-aldosterone (RAA) system on blood pressure (BP) response in patients with hypertensive emergencies and urgencies treated with intravenous enalaprilat. Thirty-five patients with a systolic BP (SBP) >210 mm Hg and/or diastolic BP (DBP) >110 mm Hg received 5 mg enalaprilat intravenously. The extent of systolic and DBP reduction was correlated with pretreatment concentrations of angiotensin II (ANGII) (SBP: r = -0.47; P = 0.006; DBP: r = -0.55; P = 0.001) and plasma renin activity (PRA) (SBP: r = -0.49; P = 0.003; DBP: r = 0.48; P = 0.007). Non-responders to enalaprilat exhibited significant lower pretreatment levels of PRA, angiotensin-converting enzyme (ACE) and ANG II compared to responders (PRA: 5.5 +/- 3.7 vs 1.1 +/- 2.2 ng/ml/h, P < 0.001; ACE: 12.8 +/- 3.5 vs 8.2 +/- 4.8 U/l, P = 0.003; ANG 11:8.7 +/- 6.2 vs 5.0 +/- 3.8 pg/ml, P = 0.04). In patients with severe hypotension following application of enalaprilat ANG II concentrations were significantly higher compared to patients with mean arterial BP reduction <25% (12.3 +/- 6.7 vs 5.6 +/- 4.0 pg/ml,P = 0.013). These data indicate that PRA and ANG II are the major determinants for BP response to enalaprilat. This relation between BP response and RAA system activity have important clinical implications for the treatment of patients with severe hypertension. Primary therapeutic failure indicates that the RAA system contributes very little to the hypertensive status of the patient. Thus, repetitive application on an ACE inhibitor in primary responders is clinically unhelpful and may result in an unnecessary delay of an effective BP reduction. In contrast, high ANG II concentrations are associated with a considerable risk for severe hypotension after enolanalaprilat application. Therefore, the status of the RAA system determines the efficacy as well as the safety of ACE inhibitor treatment in patients with severe hypertension.

Tracheal rupture after emergency intubation during cardiopulmonary resuscitation.

We describe a case of tracheal rupture following an emergency intubation during cardiopulmonary resuscitation. This complication occurring during resuscitation has not apparently been reported previously. Possible causes during the management of cardiac arrest are discussed with references to previously described cases of tracheal rupture.

Clinical application of rapid quantitative determination of cardiac troponin-T in an emergency department setting.

OBJECTIVES: We analysed the clinical use of Troponin-T compared to creatine kinase MB in a non-trauma emergency department setting. BACKGROUND: A newly established single specimen quantitative Troponin T assay allows the clinical application of this parameter. METHODS. Five-hundred Troponin T tests were provided for use by emergency physicians who could combine them with the routine laboratory tests without restriction as to the indication or number of tests per patient. The number of tests per patient, time frame, final diagnosis and additional clinical information gained were recorded. All patients were followed for at least 6 months to verify the diagnosis and to assess the occurrence of cardiac events (nonfatal AMI or cardiac death). The ability of Troponin T and creatine kinase MB tests to predict cardiac events within 6 months were compared. RESULTS: The 500 Troponin T tests were used in 249 patients (median two tests per patient (range 1-5)) within 41 days. The final diagnosis revealed coronary heart disease in 85, non-coronary heart disease in 39, non-cardiac chest pain in 86 and other diagnoses in 39 of the patients. In 14 patients with an elevated creatine kinase MB, myocardial damage could safely be ruled out by a negative Troponin T, in six patients with a normal creatine kinase MB minor myocardial damage could be detected by a positive Troponin T. During follow up 28 cardiac events were recorded. Troponin T had a significantly higher specificity, positive predictive value and proportion of correct prediction for cardiac events within 6 months compared to creatine kinase MB. CONCLUSIONS: Troponin T has proved to be an useful method for diagnosing myocardial damage in routine clinical use in the non-trauma emergency department.

Usefulness of a new rapid bedside troponin T assay in patients with chest pain.

We evaluated the usefulness of a rapid, qualitative, bedside immunoassay for cardiac-specific troponin T in patients with chest pain. A concordant result between quantitative troponin T and qualitative troponin T assay was observed in 183 (96%) tests. The sensitivity of the rapid troponin T assay for detecting acute myocardial infarction increased significantly according to the number of hours elapsed after onset of chest pain from 17% for patients presenting within 4 h to 71% for patients presenting in the time interval of greater than 8 h from onset of chest pain (P < 0.001). Specificity ranged from 83 to 93% in the three time intervals evaluated. A concordant result between CK-MB-measurement and rapid troponin T assay was observed in 159 (83%) tests. In 14/191 tests a positive rapid troponin T and a negative CK-MB assay was observed. In 9/14 (64%) cases this result was true positive for the rapid troponin T assay and in 5/14 (36%) cases false negative. As sensitivity and specificity of the rapid troponin T assay are comparable with CK-MB measurements, rapid troponin T assay is a simple and useful laboratory tool for the bedside triage in patients with chest pain.