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Early defibrillation clearly improves survival from malignant arrhythmia. However, in some cases the cause of death will only be altered from arrhythmic to nonarrhythmic. We evaluated the impact of left ventricular ejection fraction (LVEF) on trend and recovery profile of beat-to-beat cardiac output (CO) and mean arterial blood pressure (MAP) after successful defibrillation.We investigated 63 NYHA class I-III patients undergoing threshold testing in the course of insertion of an implantable cardioverter defibrillator (ICD) in monitored anaesthesia care. Preoperatively, LVEF was classified as either normal (50%), moderately (30-50%) or severely impaired (30%). CO and MAP were measured continuously throughout the implantation procedure.Arrest time and body mass index were not different between groups. CO in patients with severely and moderately reduced LVEF dropped 21% and 13% below baseline (P0.05), respectively. MAP also decreased by 26% and 17%, respectively. In contrast, 45% of patients with LVEF50% showed sympathetic activation that resulted in a 12% and 2% increase in mean values for CO and MAP, respectively. In relation to patients with LVEF50%, CO and MAP values were significantly higher after defibrillation (P0.05). Additionally, recovery of CO was prolonged in the groups with ventricular dysfunction (P0.05). Temporary post-shock pacing was observed in 40% of patients.A large number of ICD patients with restricted LVEF appears to lack the ability to quickly restore CO and MAP after successful defibrillation. Organ reperfusion may thus still be compromised.

High-dose remifentanil (1-5 microg kg-1 min-1), commonly used for cardiac surgery, has been associated with muscle rigidity, hypotension, bradycardia, and reduced cardiac output. The aim of this study was to determine an optimal lower remifentanil dose, which should be accompanied by fewer adverse events, that still effectively suppresses haemodynamic responses to typical stressful stimuli (i.e. intubation, skin incision, and sternotomy).Total i.v. anaesthesia consisted of a target-controlled propofol (2 microg ml-1) and a remifentanil infusion. Forty patients were allocated to receive either a constant infusion of remifentanil at 0.1 microg kg-1 min-1 or up-titrations to 0.2, 0.3, or 0.4 microg kg-1 min-1, respectively, 5 min before each stimulus. Subsequently, changes in heart rate and mean arterial blood pressure were recorded for 8 min. Increases exceeding 20% of baseline were considered to be of clinical relevance. Patients who exhibited these alterations were termed responders.The number of responders was less with the two higher remifentanil dosages (P0.05) while propofol target doses could either be kept at the same level or even be reduced without affecting the plane of anaesthesia. Although single phenylephrine bolus had to be applied more frequently in these two groups (P0.05), no severe haemodynamic depression was observed.Remifentanil at 0.3 and 0.4 microg kg-1 min-1 in combination with a target-controlled propofol infusion in the pre-bypass period is well tolerated. It appears to mitigate potentially hazardous haemodynamic responses from stressful stimuli equally well as higher doses when compared with data from the literature.