Vergleich des Einflusses von Bispektral-Index (BIS) versus gewichtsadaptierter Dosierung von Propofol zur Einleitung der Allgemeinanästhesie bei Erwachsenen auf die Herzfrequenz

Introduction: During intravenous induction of general anesthesia using opioids with the initiator of hypnotic propofol, transient or prolonged circulatory depression in the form of arterial hypotension and bradycardia often occur, even in standard dosages. The con-tribution of an individual overdose of propofol to this phenomenon is unknown. Fur-thermore, especially in the case of insufficient depth of anesthesia, circulatory reactions in the form of hypertension and tachycardia are observed. Unlike clinical signs, electro-encephalogram (EEG)-based cerebral monitoring not only allows the detection of suffi-cient depth of anesthesia, but also the identification and quantification of deep anesthe-sia. The current state of the data, if it is possible to reduce the extent of the circulatory reactions and in particular the occurrence of bradycardia, by administering the propofol controlled by the Bispectral Index (BIS) at the initiation of general anesthesia, is incom-plete. Patients, Materials and Methods: In this study, 240 adult patients who underwent elective surgery were randomized to a BIS-guided (target range 40-60, BIS group) propofol dose or a weight-related (2 mg/kg; standard group) assigned propofol dosage. The primary target criterion was the incidence of bradycardia (heart rate < 60/min) dur-ing anesthesia induction. Among the secondary outcomes measures included the inci-dence of patients with tachycardia (heart rate > 100/min). Results: The patients in the BIS group (n = 120) and the standard group (n = 115) did not differ in the incidence of bradycardia (31 % vs. 39 %, p = 0.18). The number of pa-tients with tachycardia (3 % vs. 14 %, p = 0.001) as well as the number of tachycardiac events (1 % vs. 4 %, p = 0.002) was significantly lower in the BIS group compared to the standard group. Conclusion: The results of this study indicate that in non-geriatric patients, manual propofol administration through BIS monitoring using the induction regime chosen in this study does not reduce bradycardia compared to manual weight-adjusted propofol administration to induce general anesthesia.