BACKGROUND The number of skin conductance fluctuations (NSCF) expresses sympathetic skin nerve activity. The response entropy (RE) measures electromyographic and electroencephalographic activity in the forehead. The state entropy (SE) measures mainly electroencephalographic activity. When the suppression of frontal muscular activity is complete, RE is equal… (More)
BACKGROUND State entropy (SE) measures electroencephalographic signals, whereas response entropy (RE) also includes frontal electromyographic activity. In the presence of electromyographic activity, the RE index is larger than the SE index, the difference being denoted as RE-Delta (RE-Delta= RE - SE). Skin conductance (SC) may be expressed by a slow… (More)
BACKGROUND Monitoring of analgesia remains a challenge during general anaesthesia. The surgical stress index (SSI) is derived from the photoplethysmographic waveform amplitude and the heart beat-to-beat interval. We evaluated the ability of SSI to measure surgical stress in patients undergoing gynaecological laparoscopy. Our hypothesis was that while… (More)
The performance of recently introduced Surgical Stress Index (SSI), based on heart rate and photoplethysmography, was estimated during sevoflurane-fentanyl and isoflurane-fentanyl anesthesia during surgical procedures. Forty ASA I-III patients were enrolled. Anesthesia was induced with fentanyl 2 mug kg(-1) and thiopentone 3-5 mg kg(-1). Tracheal intubation… (More)
BACKGROUND To study adequate antinociception during general anaesthesia, tetanic stimulus of 5-10 s duration has been used previously as a standardized nociceptive stimulus. However, such stimuli have been found to correlate poorly with intraoperative nociception. We hypothesized that an electrical tetanic stimulus of the ulnar nerve, lasting 30 s, would… (More)
Background. Inadequate analgesia during general anaesthesia may present as undesirable haemodynamic responses. No objective measures of the adequacy of analgesia exist. We aimed at developing a simple numerical measure of the level of surgical stress in an anaesthetized patient.