Dirk Elich

Active compression-decompression resuscitation: a prospective, randomized study in a two-tiered EMS system with physicians in the field

Improved cardiopulmonary circulation with active compression-decompression cardiopulmonary resuscitation (ACD-CPR) has been demonstrated in studies using different animal models and a small number of humans in cardiac arrest (CA). However, prehospital studies have shown both positive and no extra benefit of ACD-CPR on return of spontaneous circulation (ROSC), hospital admission and discharge rates. The aim of our prospective study was to compare standard manual CPR (S-CPR) with ACD-CPR as the initial technique of resuscitating patients with out-of-hospital CA, with respect to survival rates and neurological outcome. Patients with out-of-hospital CA treated by emergency medical services (EMS) personnel were randomly assigned to one of two groups (ACD-CPR versus S-CPR). Time intervals to key measures were documented by means of on-line tape-recording. Neurological outcome was assessed using standard scoring systems (cerebral and overall performance categories (CPC and OPC)). A total of 220 patients (S-CPR, n = 114: ACD-CPR, n = 106) were included in the study in a random order. The treatment groups were similar with respect to age, sex, time interval from collapse to CPR, defibrillation and first adrenaline medication. There was no difference between the ACD group and the standard CPR group in terms of ROSC (50.9% vs. 59.6%), hospital admission (33% vs. 33.3%), hospital discharge (16% vs. 14%), or CPC and OPC (1.82 vs. 2.13 and 2.06 vs. 2.25, respectively). Concerning complications of CPR, there was no difference between the groups. In our two-tiered EMS system with physician-staffed ambulances, ACD-CPR neither improved nor impaired survival rates and neurological prognosis in patients with out-of-hospital cardiac arrest. The new CPR technique did not increase the complications associated with the resuscitation effort.

Carbon dioxide levels during pre-hospital active compression-decompression versus standard cardiopulmonary resuscitation

In a prospective randomised study we investigated end-tidal carbon dioxide levels during standard versus active compression-decompression (ACD) cardiopulmonary resuscitation (CPR) assuming that the end-tital carbon dioxide reflects cardiac output during resuscitation. In each group 60 patients with out-of-hospital cardiac arrest were treated either with the standard or the ACD method. End-tidal CO2 (p(et)CO2, mmHg) was assessed with a side-stream capnometer following intubation and then every 2 min up to 10 min or restoration of spontaneous circulation (ROSC). There was no difference in p(et)CO2 between both patient groups. However, CO2 was significantly higher in patients who were admitted to hospital as compared to patients declared dead at the scene. All of the admitted patients had a p(et)CO2 of at least 15 mmHg no later than 2 min following intubation, none of the dead patients ever exceeded 15.5 mmHg. From these data we conclude that capnometry adds valuable information to the estimation of a patients prognosis in the field (threshold, 15 mmHg), but we could not detect any difference in p(et)CO2 between ACD and standard CPR.

Continuous registration of expired alcohol: a monitor of irrigation fluid absorption in transurethral prostatic surgery

Zusammenfassung. Die Einschwemmung großer Volumina von Spülflüssigkeit stellt bei der transurethralen Prostataresektion das Hauptproblem dar. Bisher verwendete Methoden weisen die Einschwemmung unzureichend nach. Erstmals setzten Hulten et al. der Spülflüssigkeit 2%igen Alkohol zu und wiesen diesen exspiratorisch diskontinuierlich mittels eines Alkoholtestgeräts nach. In dieser Studie entnahmen wir 17 Patienten unter Spinalanästhesie über eine Nasensonde kontinuierlich Exspirationsluft aus dem oberen Nasen-Rachen-Raum, die wir mittels eines NormacTM-Anästhesiegasmonitors (Fa. Datex, Helsinki) auf Alkohol untersuchten. Es sollte festgestellt werden, ob diese Methode mit klinisch ausreichender Genauigkeit eine Einschwemmung des Alkohols, der der Spülflüssigkeit zugemischt wird, aufzeigen kann. Dazu wurden neben der kontinuierlichen exspiratorischen Alkoholmessung folgende Meßwerte erhoben: Blutalkoholspiegel, endexspiratorischer Alkohol mittels Alcotest 7110, Hämatokrit, Serumnatrium und Blutgasanalyse. Bei 17 Patienten wurden 68 Messungen durchgeführt (je ein Leerwert, in 10minütigem Abstand). Erwartungsgemäß korrelierten das Serum-Natrium (r2 = 0,68) und der Hämatokrit (r2 = 0,39) schlecht mit der durch Blutalkoholbestimmung ermittelten Einschwemmung. Die Ergebnisse der exspiratorischen Alkoholbestimmung mit dem Alcotest-Gerät (r2 - 0,93) und die kontinuierliche Messung mit dem Normac (r2 = 0,85) ergaben gute Übereinstimmungen mit den Blutalkoholkontrollen. Im klinisch interessanten Bereich ab 0,3‰ Blutalkoholspiegel (entsprechend 500 bis 1000 ml Einschwemmvolumen) erreicht das kontinuierliche Monitoring der exspiratorischen Alkoholkonzentration mit einem NormacTM eine ausreichende Genauigkeit und liefert früzeitig einen zuverlässigen Hinweis für eine Einschwemmung. Abstract. The absorption of large volumes of irrigation fluid is a major problem in transurethral prostatic surgery (TUR-P). Various indicators have been tested to monitor fluid absorption with regard to continuous registration and sufficient accuracy. The volumetric fluid balance is not suitable as a routine method because of its inaccuracy. Easily accessible parameters are unspecific because of surgical bleeding (haematocrit [Hct]), or are interfered with by physiological counter-regulatory actions (serum sodium [Na] concentration). In 1986 Hulten et al. suggested adding 2% ethanol to the irrigation fluid as a marker and investigated it intermittently in the expired air with an alcohol-test appliance. In a prospective clinical study of 17 patients undergoing TUR-P under spinal anaesthesia, expiratory concentrations of alcohol that was added to the irrigation fluid (2% ethanol in Purisole, Fresenius, Bad Homburg) were monitored. Gas was continuously sampled from the nasopharynx through a nasal cannula and the ethanol concentration was measured using a modified diverting anaesthetic gas monitor (Normac, Datex, Helsinki) that allows continuous as well as early detection of the absorbed irrigation fluid with reliable accuracy for clinical use. In addition, at intervals of 10 minutes we measured blood alcohol, endtidal alcohol (Alcotest 7110, Drauml;ger, Lübeck), haematocrit, serum Na concentration, and blood gases. Sixty-eight measurements were obtained from the 17 patients. As shown in other studies, serum Na (r2 = 0.68) and Hct (r2 = 0.39) correlated poorly with the irrigation fluid as determined by serum alcohol levels. In contrast, the expiratory alcohol measurements with the alcotest 7110 (r2 = 0.93) and Normac devices (r2 = 0.85) were closely related. Continuous monitoring of the expiratory alcohol concentration with a Normac monitor closely reflects blood alcohol concentrations, and may hence serve as a useful semiquantitative monitor of irrigation fluid absorption during TUR-P.

Aktive Kompressions-Dekompressions-Reanimation (ACD-CPR)

Zusammenfassung□ HintergrundAktive Kompression, kombiniert mit aktiver Dekompression (ACD-CPR) mit Hilfe einer Druck-Saugglocke (Cardio Pump®, Ambu Int.), führt zu einer verbesserten Organdurchblutung während der kardiopulmonalen Reanimation im Vergleich zur Standardreanimationstechnik. Die Ergebnisse präklinischer Studien differieren in den verschiedenen Zentren und sind von den logistischen Gegebenheiten des jeweiligen Rettungssystems abhängig: Die Einführung der ACD-CPR führte in einigen Zentren zu einer signifikanten Erhöhung der Überlebensrate, während sie in anderen, Zentren das Reanimationsresultat nicht beeinflußte.□ Material und MethodenZiel unserer prospektiven, randomisierten Untersuchung war es, den Einfluß der aktiven Kompressions-Dekompressions-Reanimation (ACD-CPR) auf die Überlebensrate und die neurologische Langzeitprognose von Patienten mit außerklinisch aufgetretenem Kreislaufstillstand in einem notarztgestützten Rettungssystem zu untersuchen.□ ErgebnisseDie beiden Untersuchungsgruppen waren vergleichbar bezüglich Alter, Geschlecht, Vorerkrankungen, primärer Rhythmusdiagnose, Anteil an Ersthelferreanimation und der Zeitintervalle bis zum Beginn der einzelnen Reanimationsmaßnahmen. Im Gesamtkollektiv, gab es keine signifikanten Unterschiede in der Überlebensrate und der neurologischen Langzeitprognose zwischen den Gruppen. Die Nebenwirkungsrate durch das jeweilige Reanimationsverfahren war nicht unterschiedlich.□ SchlußfolgerungIn unserem notarztgestützten Rettungssystem mit relativ langen Einsatzzeiten führte die aktive Kompressions-Dekompressions-Reanimation weder zu eine rsignifikanten Erhöhung der Überlebensrate noch zu einer verbesserten neurologischen Langzeitprognose bei Patienten mit präklinischem akutem Kreislaufstillstand. Unsere Resultate stehen im Einklang mit den Ergebnisse aus Zentren mit vergleichbaren Einsatzzeiten.Summary□ BackgroundImproved cardiopulmonary circulation with active compression-decompression resuscitation (ACD-CPR) has been demonstrated in studies using different animal models and a small number of humans in cardiac arrest (CA). However, prehospital studies have shown both positive and no extra benefit of ACD-CPR on survival rates and neurologic outcome.□ Material and MethodsThe aim of our prospective study was to compare standard manual CPR (S-CPR) to ACD-CPR as the initial technique of resuscitating patients with out-of-hospital CA with respect to survival rates and neurological outcome in our two-tiered EMS system with physicians in the field.□ ResultsPatients with out-of-hospital CA treated by emergency medical services (EMS) personnel were randomly assigned to 1 of 2 groups (ACD-CPR versus S-CPR). The treatment groups were similar with respect to age, sex, time interval from collapse to CPR, defibrillation and first epinephrine medication. There was no difference between the ACD group and the standard CPR group in terms of survival rates and neurologic outcome. No differences occured concerning complications of CPR.□ ConclusionIn our two-tiered EMS system with physician-staffed ambulances ACD-CPR neither improved nor impaired the survival rates and the neurological prognosis in patients with out-of-hospital cardiac arrest. Our results are in accordance with other studies carried out in EMS systems, with first tier call-response intervals between 4 and 6 min.BACKGROUND Improved cardiopulmonary circulation with active compression-decompression resuscitation (ACD-CPR) has been demonstrated in studies using different animal models and a small number of human in cardiac arrest (CA). However, prehospital studies have shown both positive and no extra benefit of ACD-CPR on survival rates and neurologic outcome. MATERIAL AND METHODS The aim of our prospective study was to compare standard manual CPR (S-CPR) to ACD-CPR as the initial technique of resuscitating patients with out-of-hospital CA with respect to survival rates and neurological outcome in our two-tiered EMS system with physicians in the field. RESULTS Patients with out-of-hospital CA treated by emergency medical services (EMS) personnel were randomly assigned to 1 of 2 groups (ACD-CPR versus S-CPR). The treatment groups were similar with respect to age, sex, time interval from collapse to CPR, defibrillation and first epinephrine medication. There was no difference between the ACD group and the standard CPR group in terms of survival rates and neurologic outcome. No differences occurred concerning complications of CPR. CONCLUSION In our two-tiered EMS system with physician-staffed ambulances ACD-CPR neither improved nor impaired the survival rates and the neurological prognosis in patients with out-of-hospital cardiac arrest. Our results are in accordance with other studies carried out in EMS systems, with first tier call-response intervals between 4 and 6 min.