OBJECTIVE:The induction of deep cerebral hypothermia via ice-cold saline aortic flush during prolonged ventricular fibrillation cardiac arrest, followed by hypothermic stasis and delayed ...resuscitation (emergency preservation and resuscitation), improved neurologic outcome after cardiac arrest in pigs, as compared to conventional resuscitation. We hypothesized that emergency preservation and resuscitation with chest compressions would further improve outcome in the same model.
DESIGN:Prospective experimental study.
SETTING:University research laboratory.
SUBJECTS:Twenty-four female, large, white breed pigs (27–37 kg).
INTERVENTIONS:Fifteen minutes of ventricular fibrillation cardiac arrest were followed by 20 mins of resuscitation with chest compressions (control, n = 8), deep cerebral hypothermia via 200 mL/kg 4°C saline aortic flush and hypothermic stasis (emergency preservation and resuscitation, n = 8), and emergency preservation and resuscitation combined with chest compressions (emergency preservation and resuscitation plus chest compressions, n = 8). At 35 mins after cardiac arrest, cardiopulmonary bypass was initiated, followed by defibrillation. Mild hypothermia was continued for 20 hrs. Pigs were evaluated after 9 days using a neurologic deficit (neurologic deficit score100% = brain dead; 0%–10% = normal) and an overall performance category score (overall performance category score1 = normal; 2 = slightly handicapped; 3 = severely handicapped; 4 = comatose; 5 = dead/brain dead).
MEASUREMENTS AND MAIN RESULTS:Brain temperature decreased from 38.5°C to 15.3°C ± 3.3°C in the emergency preservation and resuscitation group, and to 11.3°C ± 1.2°C in the emergency preservation and resuscitation plus chest compressions group. In the control group, restoration of spontaneous circulation was achieved in four out of eight pigs, and one survived to 9 days. In the emergency preservation and resuscitation group, restoration of spontaneous circulation was achieved in seven out of eight pigs and five survived; in the emergency preservation and resuscitation plus chest compressions group, all had restoration of spontaneous circulation and seven survived (restoration of spontaneous circulation, p = .08). Neurologic outcome for (median and interquartile range) the control group included overall performance category score of 3, neurologic deficit score of 45%; for the emergency preservation and resuscitation group, overall performance category score was 3 (2–5) and neurologic deficit score was 45% (36; 50) and in the emergency preservation and resuscitation plus chest compressions group, overall performance category score was 2 (1–3) and neurologic deficit score was 13% (5; 21) (overall performance category score, p = .04; neurologic deficit score emergency preservation and resuscitation vs. emergency preservation and resuscitation plus chest compressions, p = .003).
CONCLUSIONS:Emergency preservation and resuscitation by deep cerebral hypothermia combined with chest compressions during prolonged cardiac arrest in pigs are feasible and improve neurologic outcome.
Zusammenfassung
Akute Stoffwechselentgleisungen können für Erwachsene in Abhängigkeit von ihrem Ausmaß lebensbedrohlich sein. Dementsprechend sind eine rasche umfassende Diagnostik und Therapie sowie ...eine enge Überwachung der Vitalparameter und Laborbefunde erforderlich. Bei der Therapie, die sich bei der ketoazidotischen (DKA) und hyperglykämisch-hyperosmolaren (HHS) Form nicht wesentlich unterscheidet, kommt dem Ausgleich des meist beträchtlichen Flüssigkeitsdefizits mit mehreren Litern einer physiologischen kristalloiden Lösung eine vorrangige Rolle zu. Bei den Elektrolyten ist insbesondere auf eine ausgeglichene Serum-Kalium-Konzentration zu achten. Normal-Insulin oder rasch wirksame Analoga können initial als i.v.-Bolus verabreicht werden, in der Folge jedoch kontinuierlich über einen Perfusor. Die Umstellung auf eine subkutane Insulintherapie soll erst bei ausgeglichenem Säure-Basen-Haushalt und zufriedenstellender Glykämie erfolgen.
Background: Mild therapeutic hypothermia (MTH) improves neurological outcome in patients after cardiac arrest. From animal and human studies it appears that hypothermia impairs renal function. The ...aim of this study was to examine the effects of MTH on renal function in humans.
Methods: Patients were participants recruited in one of the centres of the hypothermia after cardiac arrest-multicenter trial. We measured serum creatinine and creatinine clearance (
C
Cr) within 24
h of MTH, at 4 hourly intervals. Patients were followed for acute renal failure and need for renal supportive therapy for 28 days.
Results: We included 60 patients (32 hypothermic, 28 normothermic). Median serum creatinine on admission was {119
μmol/l (IQR 108–133)} {1.35
mg/dl (IQR 1.22–1.50)} in hypothermic and {114
μmol/l (IQR 99–131)} {1.29
mg/dl (IQR 1.12–1.48)} in normothermic patients, and decreased to {69
μmol/l (IQR 62–84)} {0.78
mg/dl (IQR 0.70–0.95)} in the hypothermic group and to {88
μmol/l (IQR 71–123)} {1.00
mg/dl (IQR 0.80–1.39)} in the normothermic group within 24
h.
C
Cr was decreased on admission. Within 24
h
C
Cr improved to normal values in normothermic patients 1.53
ml/s (IQR 1.15–2.35) {92
ml/min (IQR 69–141)} and remained low in hypothermic patients 0.88
ml/s (IQR 0.63–1.38) {53
ml/min (IQR 38–83)} (
P=0.0006). No difference was found between the groups in the development of acute renal failure or the need for renal supportive therapy.
Conclusion: Twenty four hours of MTH was associated with a delayed improvement in renal function. This was not reflected in the serum creatinine values, which were low in the hypothermic group. This transient impaired renal function appeared to be completely reversible within 4 weeks.
Contexto: A terapêutica com hipotermia ligeira (MTH) melhora o prognóstico neurológico nos doentes após paragem cardı́aca. Dos estudos animais e humanos parece que a hipotermia afecta a função renal. O objectivo deste estudo é examinar os efeitos da MTH na função renal em humanos.
Métodos: Os doentes foram recrutados de um dos centros do ensaio multicêntrico de hipotermia após paragem cardı́aca. Foi medida a creatinina sérica e a clearance da creatinina (
C
Cr) durante 24
h de MTH, em intervalos de 4 horas. Os doentes foram seguidos durante 28 dias, durante os quais se observou o desenvolvimento de Insuficiência renal e a necessidade de terapêutica de suporte dialı́tico.
Resultados: Foram incluı́dos no estudo 60 doentes (32 hipotermicos, 28 normotermicos). A creatinina sérica média na admissão foi de (119
μmol/l (IQR 108–133) (1.35
mg/dl (IQR 1.22–1.50) no grupo hipotermico e (114
μmol/l (IQR 99–131) (1.29
mg/dl (IQR 1.12–1.48) nos doentes normotérmicos, e diminuı́da em 24
horas para (69
μmol/l (IQR 62–84) (0.78
mg/dl (IQR 0.70–0.95) no grupo hipotérmico e para (88
μmol/l (IQR 71–123) (1.00
mg/dl (IQR 0.80–1.39) no grupo normotermico. A
C
Cr estava diminuı́da na admissão. Após 24
h a
C
Cr melhorou para valores normais nos doentes normotermicos (1.53
ml/s(IQR 1.15–2.35) (92
ml/min(IQR 69–141)) e permaneceu baixa nos doentes do grupo hipotermico (0.88
ml/s(IQR 0.63–1.38) (53
ml/min(IQR 38–83) (
P=0.0006). Não foi encontrada nenhuma diferença entre os grupos no desenvolvimento de insuficiência renal aguda ou na necessidade de terapêutica de suporte renal.
Conclusão: As 24
h de MTH foi associada a um atraso na melhoria da função renal. Isto não se reflectiu nos valores séricos da creatinina, que foram baixos no grupo da hipotermia. Esta alteração transitória da função renal parece estar completamente revertida dentro de 4 semanas.
Antecedentes: La hipotermia terapéutica leve (MTH) mejora el resultado neurológico en pacientes después de paro cardı́aco. A partir de estudios humanos y en animales se ve que la hipotermia daña la función renal. El objetivo de este estudio fue examinar los efectos de la MTH sobre la función renal en humanos.
Métodos: los pacientes fueron los reclutados en uno de los centros para participar en el estudio multicéntrico de hipotermia después del paro cardı́aco. Medimos creatinina sérica y clearance de creatinina(
C
Cr) dentro de 24
h de MTH, en 4 intervalos horarios. Los pacientes fueron seguidos buscando falla renal aguda y necesidad de terapia de apoyo renal por 28 dı́as.
Resultados: Incluimos 60 pacientes (32 hipotérmicos, 28 normotérmicos). La mediana de creatinina sérica al ingreso fue {119
μmol/l (IQR 108–133)} {1.35
mg/dl(IQR 1.22–1.50)} en los pacientes hipotérmicos y {114
μmol/l (IQR 99–131)} {1.29
mg/dl (IQR1.12–1.48)} en pacientes normotérmicos, y disminuyó a {69
μmol/l (IQR 62–84)} {0.78mg/dl(IQR 0.70-0.95)} en el grupo hipotérmico y a {88
μmol/l (IQR 71–123)} {1.00mg/dl (IQR 0.80–1.39)} en el grupo normotérmico dentro de las 24
h. El
C
Cr estaba disminuido al ingreso. Dentro de 24
h mejoró hasta valores normales en pacientes normotérmicos 1.53
ml/s (IQR 1.15–2.35) {92
ml/min (IQR 69–141)} y se mantuvo bajo en los pacientes hipotérmicos 0.88ml/s (IQR 0.63–1.38) {53
ml/min (IQR 38–83)} (
P=0.0006). No se encontró diferencia entre los grupos en el desarrollo de falla renal aguda o en la necesidad de terapia de apoyo renal.
Conclusión: Se asoció las 24
horas de MTH con una demora en la mejorı́a de la función renal. Esto no se reflejó en los valores séricos de creatinina, que eran bajos en el grupo hipotérmico. Esta función renal transitoriamente dañada resultó estar completamente reversible dentro de 4 semanas.
We analyzed the medical records of patients with an established diagnosis of acute renal infarction to identify predictive parameters of this rare disease. Seventeen patients (8 male) who were ...admitted to our emergency department between May 1994 and January 1998 were diagnosed by contrast-enhanced computed tomography (CT) as having acute renal infarction (0.007% of all patients). We screened the records of the 17 patients for a history with increased risk for thromboembolism, clinical symptoms, and urine and blood laboratory results known to be associated with acute renal infarction. A history with increased risk for thromboembolism with 1 or more risk factors was found in 14 of 17 patients (82%); risk factors were atrial fibrillation (n = 11), previous embolism (n = 6), mitral stenosis (n = 6), hypertension (n = 9), and ischemic cardiac disease (n = 7). All patients reported persisting pain predominantly from the flank (n = 11), abdomen (n = 4), and lower back (n = 2). On admission, elevated serum lactate dehydrogenase was found in 16 (94%) patients, and hematuria was found in 12 (71%) of 17 patients. After 24 hours all patients showed an elevated serum lactate dehydrogenase, and 14 (82%) had a positive test for hematuria. Our findings suggest that in all patients presenting with the triad--high risk of a thromboembolic event, persisting flank/abdominal/lower back pain, elevated serum levels of lactate dehydrogenase and/or hematuria within 24 hours after pain onset--contrast-enhanced CT should be performed as soon as possible to rule out or to prove acute renal infarction.
OBJECTIVE:Monitoring of ventilation performance during cardiopulmonary resuscitation would be desirable to improve the quality of cardiopulmonary resuscitation. To investigate the potential for ...measuring ventilation rate and inspiration time, we calculated the correlation in waveform between transthoracic impedance measured via defibrillator pads and tidal volume given by a ventilator.
DESIGN:Clinical study.
SETTING:Emergency department of a tertiary care university hospital.
PATIENTS:A convenience sample of mechanical ventilated patients (n = 32), cardiac arrest patients (n = 20), and patients after restoration of spontaneous circulation (n = 31) older than 18 were eligible.
INTERVENTIONS:The Heartstart 4000SP defibrillator (Laerdal Medical Cooperation, Stavanger, Norway) with additional capabilities of recording thoracic impedance changes was used.
MEASUREMENTS AND MAIN RESULTS:The relationship between impedance change and tidal volume (impedance coefficient) was calculated. The mean (sd) correlations between the impedance waveform and the tidal volume waveform in the patient groups studied were .971 (.027), .969 (.032), and .967 (.035), respectively. The mean (sd) impedance coefficient for all patients in the study was .00194 (.0078) Ω/mL, and the mean (sd) specific (weight-corrected) impedance coefficient was .152 (.048) Ω/kg/mL. The measured thorax impedance change for different tidal volumes (400–1000 mL) was approximately linear.
CONCLUSIONS:The impedance sensor of a defibrillator is accurate in identifying tidal volumes, when chest compressions are interrupted. This also allows quantifying ventilation rates and inspiration times. However this technology, at its present state, provides only limited practical means for exact tidal volume estimation.
OBJECTIVE:Several cooling methods have been investigated for inducing mild hypothermia (33–36°C) after cardiac arrest, brain trauma, or stroke. To achieve its best effect, therapeutic hypothermia has ...to be applied very early after the ischemic insult; otherwise, the beneficial effect would be diminished or even abrogated. The aim of this study was to investigate the effectiveness and safety of extracorporeal venovenous cooling as compared with endovascular cooling.
DESIGN:Swine were cooled in a randomized crossover design from 38°C to 33°C brain temperature, either with extracorporeal venovenous cooling or with endovascular cooling.
SETTING:Laboratory investigation.
SUBJECTS:Six swine of human size (85 to 101 kg).
INTERVENTIONS:Swine were randomly cooled with the first device, and after achieving the target brain temperature, re-warmed via the same technique and with heating lamps to baseline temperature. Then the other catheter was inserted and cooling was performed with the second device.
MEASUREMENTS:Brain, pulmonary artery and tympanic temperature, blood pressure, and heart rate were recorded continuously. Laboratory samples, including free hemoglobin, were taken at predefined temperature points during cooling. Comparisons between and within (baseline vs. 33°C) the treatment groups were performed with the paired Student’s t-test.
MAIN RESULTS:The time needed to reduce brain temperature from 38.0°C to 33.0°C was 41 ± 17 mins with venovenous cooling and 126 ± 37 mins with endovascular cooling (p = .001). Heart rate and mean arterial pressure decreased moderately during cooling and were significantly lower at 33°C than at baseline in both groups, without differences between groups. None of the swine developed significant hemolysis, arrhythmias, or bleeding.
CONCLUSIONS:Extracorporeal venovenous cooling was an effective and safe method to rapidly induce therapeutic mild hypothermia in human-sized swine. It seems to be promising for further application and investigation in 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 I18-25 cm; group II25.1-33 cm; and group III33.1-47.5 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 ≥10 mm Hg and 34.2% (n = 512) exhibited a discrepancy of ≥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.
Summary
Background and aim
Systems of care to treat acute ST-elevation myocardial infarction (STEMI) have been developed world wide in the past decade. Their effectiveness can only be proven by ...including and analyzing outcome data of consecutive patients in registries, which is not the case in the majority of STEMI networks. This study investigates 1-year mortality in STEMI patients in Vienna included over a 14 months time interval. The Vienna STEMI network is organized by a specific rotational system and offers both, primary percutaneous intervention (PPCI) and thrombolytic therapy (TT) as reperfusion strategies according to the recent guidelines.
Methods
At the time of investigation, the Vienna STEMI network consisted of the Viennese Ambulance Systems and five high-volume interventional cardiology departments. This network has been organized in order to increase the number of STEMI patients admitted for PPCI and to offer the fastest available reperfusion strategy, in the majority PPCI but in selected patients also TT (STEMI of short duration, mainly anterior wall MI and mainly patients younger than 75 years), followed by rescue PCI in non-responders and elective angiography with/without PCI in responders to TT during the index hospital stay.
Results
One-year all-cause mortality rates in the Vienna STEMI network by use of the fastest available reperfusion strategy were 13.4 % in patients who received reperfusion therapy after 2 h of symptom onset and 7.4 % in patients treated within 2 h; (
p
= 0.017). Whereas PPCI and TT demonstrated a nonsignificant difference in 1-year mortality rates when initiated within 2 h of symptom onset (10.0 % vs 5.7 %;
p
= 0.59), PPCI was more effective in acute STEMI of > 2 h duration as compared to TT but this difference did not reach statistical significance (12.1 % vs 18.2 %;
p
= 0.07).
Conclusions
The reassuring long-term results of the Viennese STEMI network are another example of a specific regional system of care to offer timely diagnosis, transfer and reperfusion in patients with STEMI. In contrast to other metropolitan areas where TT has almost completely abandoned, we still use pharmacological reperfusion as a backup in case of expected and unacceptable time delays for PPCI in order to reduce myocardial damage especially in patients with larger infarctions of short duration with a low risk of bleeding complications.
Summary Background No accurate, independent biomarker has been identified that could reliably predict neurological outcome early after cardiac arrest. We speculated that brain natriuretic peptide ...(BNP) measured at hospital admission may predict patient outcome. Methods BNP-levels were measured in 155 comatose cardiac arrest survivors (108 male, 58 years IQR 49–68) (median time to ROSC 11 min; IQR 20–30) during a 6-year study period. Cardiovascular co-morbidities and resuscitation history were assessed according to the Utstein-style and patients were followed for 6-month neurological outcome measured by cerebral performance category (CPC) and survival. Results Seventy patients (45%) suffered from unfavourable neurological outcome and 79 deaths (51%) occurred during the first 6 months. BNP was significantly associated with an adverse neurological outcome and mortality, independent of the prearrest health condition and cardiac arrest characteristics (median 60 pg/ml; IQR 10–230). Adjusted odds ratios for poor neurological outcome at 6 months were 1.14 (95% CI 0.51–2.53), 1.76 (95% CI 0.80–3.88) and 2.25 (95% CI 1.05–4.81), for increasing quartiles of BNP as compared to the lowest quartile. Adjusted odds ratios for mortality until 6 months were 1.09 (95% CI 0.35–3.40), 2.81 (0.80–9.90) and 4.7 (1.27–17.35) compared to the lowest quartile, respectively. Conclusion Brain natriuretic peptide levels on admission predict neurological outcome at 6 months and survival after cardiac arrest.
