Single domain spin manipulation by electric fields in strain coupled artificial multiferroic nanostructures.

We demonstrate in situ 90° electric field-induced uniform magnetization rotation in single domain submicron ferromagnetic islands grown on a ferroelectric single crystal using x-ray photoemission electron microscopy. The experimental findings are well correlated with micromagnetic simulations, showing that the reorientation occurs by the strain-induced magnetoelectric interaction between the ferromagnetic nanostructures and the ferroelectric crystal. Specifically, the ferroelectric domain structure plays a key role in determining the response of the structure to the applied electric field, resulting in three strain-induced regimes of magnetization behavior for the single domain islands.

Effect of exercise on transdermal nicotine release in healthy habitual smokers.

OBJECTIVE: Transdermal nicotine patches have become a frequently prescribed tool in smoking cessation programs during the past years. However, there is circumstantial evidence that transdermal nicotine release substantially varies with physical activity producing toxic plasma concentrations that may account for severe adverse events. METHODS: We, therefore, compared nicotine release from two different transdermal nicotine systems (TDNS) at rest and during strenuous physical activity in a two-period crossover study in healthy smokers (n = 10). The subjects were randomly assigned to receive either 21 mg/day of formulation A or B on study Day 1 and 2. Patches were applied eight hours before starting standardized physical activity, and nicotine concentrations were measured in plasma and topically in the tissue layers underneath the application site by microdialysis. RESULTS: There was no difference between groups in the mean values for area under the time-concentration curve at rest from 0 - 8 hours AUC(0-8) (p < 0.799) and during exercise from 8 - 11 hours AUC(8-11) (p < 0.878). C(max) values between groups with C(max) values of 16.4 +/- 9.5 ng/ml and 16.0 +/- 10.7 ng/ml at rest (p < 0.919, NS) and 10.05 +/- 6.8 ng/ml and 10.2 +/- 6.9 ng/ml (p < 0.959, NS) during exercise did not differ significantly. Nicotine tissue concentrations increased two-fold during exercise versus baseline (p < 0.878). Skin blood flow increased significantly during exercise compared with baseline (p < 0.001). No adverse events were observed. CONCLUSION: The present study provides evidence that transdermal nicotine release from TDNS increases during exercise. However, this increase has no significant effect on overall plasma pharmacokinetics. Our pharmacokinetic data further indicate that the two TDNS formulations are equivalent during conditions of rest and exercise.

[Effects of terazosine and atenolol on serum lipids in essential hypertension]. / Effekte von Terazosin und Atenolol auf die Serumlipide bei essentieller Hypertonie.

BACKGROUND: Only a few studies have evaluated the efficacy of alpha-blocking agents in combination with other classes of antihypertensive agents, especially in patients not adequately controlled by monotherapy. As alpha-blockers have an additional beneficial effect on serum lipids, it seems reasonable to use them instead of beta-blockers or diuretics in insufficiently treated hypertensive patients with hyperlipidemia. MATERIALS AND METHODS: All patients with insufficient blood pressure control with either a calcium channel blocker or an ACE inhibitor and evidence of hyperlipidemia (total serum cholesterol > 5.69 mmol/L) were included into an open, randomized and prospective study to evaluate the effects of terazosin and atenolol on lipid profile in hypertensive patients. The patients received either terazosin (n = 26; dose 1 to 10 mg) or atenolol (n = 28; dose 25 to 100 mg). Blood pressure was assessed by 24-hour ambulatory blood pressure measurement and serum lipids were evaluated at the time of inclusion and 12 weeks later. RESULTS: Blood pressure was similar after 12 weeks of treatment (atenolol: 129 (9)/75 (7) mm Hg; terazosin: 128 (11)/75 (9) mm Hg) and total cholesterol was significantly reduced after 12 weeks of treatment (atenolol: Diff 0-12 weeks: 7.29 (1.32) versus 6.62 (1.14 mmol/L, p = 0.006; terazosin: 7.34 (0.93) versus 6.67 (0.85) mmol/L, p = 0.002). In the terazosin group, HDL-cholesterol increased and triglycerides decreased significantly (Diff 0-12 weeks: HDL-chol: 1.55 (0.31) versus 1.63 (0.44) mmol/L, p = 0.04; TG: 1.93 (1.17) versus 1.34 (0.64) mmol/L, p = 0.03). Comparing both groups a significant difference was found with regard to HDL-cholesterol and triglycerides (atenolol versus terazosin: HDL-chol: -0.05 (0.12) versus +0.08 (0.1) mmol/L, p = 0.04; TG: -0.18 (0.61) versus--0.59 (0.6), p = 0.03). CONCLUSIONS: The alpha-blocker terazosin is as effective as atenolol when combined with either an ACE inhibitor or a calcium-channel blocker as a part of a multidrug regimen to achieve sufficient blood pressure control. In addition, terazosin is superior to atenolol with regard to the effect on the lipid profile of hypertensive and hyperlipidemic patients and seems therefore a reasonable alternative to beta-blockers in hypertensive patients with hyperlipidemia.

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.

Effects of bystander first aid, defibrillation and advanced life support on neurologic outcome and hospital costs in patients after ventricular fibrillation cardiac arrest.

OBJECTIVE: To evaluate the effects of basic life support, time to first defibrillation and emergency medical service arrival time on neurologic outcome and expenses for hospital care in patients after cardiac arrest. SETTING: Large urban emergency medical services system and emergency department in a 2000-bed university hospital. DESIGN: Outcome and cost benefit analysis of patients admitted to the hospital after witnessed, out-of-hospital, ventricular fibrillation cardiac arrest from October 1, 1991, until December 31, 1997. PATIENTS: Out of 1054 patients with out-of-hospital cardiac arrest, 276 were eligible. MEASUREMENTS AND RESULTS: The effects of basic and advanced life support measures on neurologic outcome and hospital expenses were evaluated. In contrast to intubation (odds ratio 1.08; 95% CI: 0.51-2.31; p=0.84), basic life support (odds ratio 0.44; 95% CI: 0.24-0.77; p=0.004) and time to first defibrillation (odds ratio 1.08; 95% CI: 1.03-1.13; p=0.001) were significantly correlated with good neurologic outcome. Among the patients who did not receive basic life support, the average cost per patient with good neurologic outcome significantly increased with the delay of the first defibrillation (p<0.001). CONCLUSIONS: In contrast to intubation, bystander basic life support and time to first defibrillation were significantly associated with good neurologic outcome and resulted in fewer expenses spent on in-hospital efforts.

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.

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.

Simultaneous comparison of thoracic bioimpedance and arterial pulse waveform-derived cardiac output with thermodilution measurement.

OBJECTIVE: To compare the accuracy and reliability of thoracic electrical bioimpedance (TEB) and the arterial pulse waveform analysis with simultaneous measurement of thermodilution cardiac output (TD-CO) in critically ill patients. DESIGN: Prospective data collection. SETTING: Emergency department and critical care unit in a 2,000-bed inner-city hospital. PATIENTS: A total of 29 critically ill patients requiring invasive hemodynamic monitoring for clinical management were prospectively studied. INTERVENTIONS: Noninvasive cardiac output was simultaneously measured by a TEB device and by analysis of the arterial pulse waveform derived from the finger artery. Invasive cardiac output was determined by the thermodilution technique. MEASUREMENTS AND MAIN RESULTS: A total of 175 corresponding TD-CO and noninvasive hemodynamic measurements were collected in 30-min intervals. They revealed an overall bias of 0.34 L/min/m2 (95% confidence interval, 0.24-0.44 L/min/m2; p < .001) for the arterial pulse waveform analysis and of 0.61 L/min/m2 (95% confidence interval, 0.50-0.72 L/min/m2; p < .001) for the TEB. In 39.4% (n = 69) of all measurements, the discrepancy between arterial pulse waveform analysis and TD-CO was >0.50 L/min/m2. The discrepancies of the arterial pulse waveform analysis correlated positively with the magnitude of the cardiac index (r2 = 0.29; p < .001). In 56.6% (n = 99) of all measurements, the discrepancy between TEB and TD-CO was >0.50 L/min/m2. The magnitude of the discrepancies of the TEB was significantly correlated with age (r2 = 0.17; p = .02). Measurements were in phase in 93.2% of all arterial pulse waveform analysis and in 84.9% of all TEB readings (p < .001). CONCLUSIONS: The arterial pulse waveform analysis exhibits a greater accuracy and reliability as compared with the TEB with regard to overall bias, number of inaccurate readings, and phase lags. The arterial pulse waveform analysis may be useful for the monitoring of hemodynamic changes. However, both methods fail to be a substitute for the TD-CO because of a substantial percentage of inaccurate readings.

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.

Accuracy of oscillometric blood pressure measurement according to the relation between cuff size and upper-arm circumference in critically ill patients.

OBJECTIVE: To evaluate the accuracy of oscillometric blood pressure measurement according to the relation between cuff size and upper-arm circumference in critically ill patients. DESIGN: Prospective data collection. SETTING: Emergency department in a 2,000-bed inner city hospital. PATIENTS: Thirty-eight patients categorized into three groups according to their upper-arm circumference (group I: 18-25 cm; group II: 25.1-33 cm; and group III: 33.1-47.5 cm) were enrolled in the study protocol. INTERVENTIONS: In each patient, all three cuff sizes (Hewlett-Packard Cuff 40401 B, C, and D) were used to perform an oscillometric blood pressure measurement at least within 3 mins until ten to 20 measurements for each cuff size were achieved. Invasive mean arterial blood pressure measurement was done by cannulation of the contralateral radial artery with direct transduction of the systemic arterial pressure waveform. The corresponding invasive blood pressure value was obtained at the end of each oscillometric measurement. MEASUREMENT AND MAIN RESULTS: Overall, 1,494 pairs of simultaneous oscillometric and invasive blood pressure measurements were collected in 38 patients (group I, n = 5; group II, n = 23; and group III, n = 10) over a total time of 72.3 hrs. Mean arterial blood pressure ranged from 35 to 165 mm Hg. The overall discrepancy between oscillometric and invasive blood pressure measurement was -6.7+/-9.7 mm Hg (p<.0001), if the recommended cuff size according to the upper-arm circumference was used (539 measurements). Of all the blood pressure measurements, 26.4% (n = 395) had a discrepancy of > or =10 mm Hg and 34.2% (n = 512) exhibited a discrepancy of > or =20 mm Hg. No differences between invasive and noninvasive blood pressure measurements were noted in patients either with or without inotropic support (-6.6 + 7.2 vs. -8.6 + 6.8 mm Hg; not significant). CONCLUSION: The oscillometric blood pressure measurement significantly underestimates arterial blood pressure and exhibits a high number of measurements out of the clinically acceptable range. The relation between cuff size and upper-arm circumference contributes substantially to the inaccuracy of the oscillometric blood pressure measurement. Therefore, oscillometric blood pressure measurement does not achieve adequate accuracy in critically ill patients.

Hypertension in patients presenting with epistaxis.

STUDY OBJECTIVE: We sought to evaluate whether patients with epistaxis in the emergency department have a higher arterial blood pressure compared with patients with other medical emergencies and to study the association of elevated blood pressure during epistaxis with sustained arterial hypertension. METHODS: In a prospective, cross-sectional, prevalence study we compared arterial blood pressure on admission in the ED in 213 consecutive patients treated for epistaxis with that of 213 sex- and age-matched control subjects. In 33 of those patients with elevated blood pressure during epistaxis, we evaluated the prevalence of sustained arterial hypertension. Main outcome measures were arterial blood pressure during epistaxis and evidence of sustained arterial hypertension, as determined by 24-hour ambulatory blood pressure measurement. RESULTS: Patients with epistaxis had significantly higher blood pressure values compared with those of control patients (systolic blood pressure 161+/-30 versus 144+/-22 mm Hg, P<.001; diastolic blood pressure 84+/-19 versus 75+/-15 mm Hg, P <.001). Of 33 (30%) of 108 patients with elevated blood pressure during epistaxis who were further evaluated, 26 (79%) patients were classified as having sustained arterial hypertension. Nine (27%) patients with sustained arterial hypertension were unaware of a history of hypertension. Patients with sustained arterial hypertension had significantly more episodes of epistaxis compared with patients with elevated blood pressure during epistaxis and no sustained arterial hypertension (mean 5 versus 1; P=.004). CONCLUSION: Patients with epistaxis have a higher blood pressure compared with that of control patients. Twenty-six (79%) of 33 patients with elevated blood pressure during epistaxis had sustained arterial hypertension. Nine (27%) of these patients were unaware of a history of hypertension. Continued management of patients with epistaxis and high blood pressure should include confirmation or exclusion of sustained arterial hypertension by 24-hour ambulatory blood pressure recording.

Mutations in the carboxy terminus of the beta and gamma subunits of the epithelial sodium channel are not present in patients with hypertensive crisis.

BACKGROUND: The pathophysiology of hypertensive crises is poorly understood. To date, no information is available about genetic determinants underlying the individual risk for development of hypertensive urgencies or emergencies. Recently, mutations in the beta subunit (h beta ENaC) and the gamma subunit (h gamma ENaC) of the human epithelial sodium channel (hENaC) have been shown to result in excessive elevation of blood pressure in patients with Liddle's syndrome. METHODS: Using polymerase chain reaction and direct sequencing of amplification products we have screened 90 consecutive out-patients with hypertensive urgency or hypertensive emergency for the presence of mutations in the carboxy terminus of these genes. Furthermore, serum potassium concentrations were determined in all 90 patients, and serum aldosterone levels and plasma renin activity were measured in a subset of 34 patients. RESULTS: Among 71 patients with hypertensive urgency (78.9%) and 19 patients with hypertensive emergency (21.1%) not one individual showed a mutation in genomic DNA extending from codon 532 to codon 637 of h beta ENaC and from codon 525 to codon 651 of h gamma ENaC. Twelve of 90 patients showed mild hypokalaemia (13.3%), 16 of 34 patients had a plasma renin activity below the lower normal range (47.1%) and one of 34 patients had a low serum aldosterone concentration (2.9%). CONCLUSIONS: The present study clearly demonstrates the absence of mutations in the carboxy terminus of the h beta ENaC and h gamma ENaC gene of hENaC in an Austrian cohort of 90 patients suffering from 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.

Noninvasive assessment of cardiac output in critically ill patients by analysis of the finger blood pressure waveform.

OBJECTIVE: To assess whether the measurement of cardiac output by computer-assisted analysis of the finger blood pressure waveform can substitute for the thermodilution method in critically ill patients. DESIGN: Prospective data collection. SETTING: Emergency department in a 2000-bed inner city hospital PATIENTS: Forty-six critically ill patients requiring invasive monitoring for clinical management were prospectively studied. INTERVENTIONS: Under local anesthesia a 7-Fr pulmonary artery catheter was inserted via the central subclavian or jugular vein. Cardiac output was determined by the use of a cardiac output computer and injections of 10 mL ice-cold glucose 5%. Noninvasive cardiac output was calculated from the finger blood pressure waveform by the use of the test software program. MEASUREMENTS AND MAIN RESULTS: Three hundred twenty-three pairs of invasive and noninvasive hemodynamic measurements were collected in intervals of 30 mins from 46 patients (mean age 61.9 +/- 12.4 yrs; 35 male, 11 female). The average cardiac index during the study period was 2.83 L/min/m2 (range 0.97 to 5.56). The overall discrepancy between both measurements was 0.14 L/min/m2 (95% confidence interval: 0.10-.018, p < .001). Seventy-five (23.2%) measurements had an absolute discrepancy > +/- 0.50 L/min/m2. Noninvasive and invasive comparisons of mean differential cardiac output were out of phase for 9.7% of all readings. CONCLUSION: Computer-assisted analysis of finger blood pressure waveform to assess cardiac output is not a substitute for the thermodilution method due to a high percentage (23.2%) of inaccurate readings; however, it may be a useful tool for the detection of relative hemodynamic trends in critically ill patients.

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.

Fatal pulmonary edema after nitric acid inhalation.

We report a case of acute inhalation injury of nitric acid in a 56-year old white male. The patient presented conscious and dyspnoic at the emergency department after cleaning a copper chandelier with nitric acid. He had to be intubated 2 h after admission and mechanically ventilated because of fulminant respiratory insufficiency. As all sources of mechanical ventilation failed, extracorporeal membrane oxygenation had to be established 7 h after admission. With the additional use of surfactant and low dose inhalation therapy with nitric oxide (NO), the patient could be stabilised for 3 days and lung function improved temporarily. Despite all efforts the patient died at the fourth day from refactory respiratory failure. Pathologic examination revealed massive pulmonary edema without signs of inflammation. Thus, nitric acid inhalation induced pulmonary edema appears to be a most severe situation in which even most modern therapeutic interventions fail. As, in respect of recent literature and our case no promising therapy for nitric acid inhalation pulmonary edema is available, our efforts have to be directed towards prevention of nitric acid exposure.

Cardiorespiratory consequences to hobble restraint.

UNLABELLED: Mechanical restraints in agitated, violent psychiatric patients are still sometimes in use in the initial phase of emergency treatment, especially when patients are taken to hospital by law enforcement. Sudden death has occurred in persons in hobble restraint. Cardiopulmonary response to prone or upright hobble restraint for three minutes was investigated in six male volunteers in randomised crossover trial. RESULTS: No change was observed in the investigated cardiopulmonary parameters after hobble restraint in the upright position. After hobble restraint in the prone position, mean forced vital capacity decreased by 39.6%, mean forced exspiratory volume by 41%, mean end-tidal carbon dioxide increased by 14.7%, mean heart rate decreased by 21.3%, mean systolic blood pressure decreased by 32.3%, mean diastolic blood pressure decreased by 26.1% and mean cardiac output decreased by 37.4% (P for all reported changes < 0.01). CONCLUSION: Hobble restraint in the prone position leads to a dramatic impairment of hemodynamics and respiration. Upright position and frequent control of vital parameters are necessary to prevent a possibly fatal outcome in persons in hobble restraint.

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.