Prediction of the haemodynamic response to tracheal intubation: comparison of laser-Doppler skin vasomotor reflex and pulse wave reflex

Abstract

Background. The laser-Doppler skin vasomotor reflex (SVmR) caused by tetanic stimulation of the ulnar nerve may be a test that can predict the haemodynamic response to tracheal intubation. A decrease in pulse wave amplitude (pulse wave reflex, PWR) may be an alternative index of this response. We compared the abilities of PWR and SVmR to predict the haemodynamic response to tracheal intubation and studied how alfentanil, muscle relaxation, stimulation site and stimulation pattern affected the two reflexes.

Tetanic stimulus of ulnar nerve as a predictor of heart rate response to skin incision in propofol–remifentanil anaesthesia †

“…In previous trials, rather short-lasting (5 or 10 s) tetanic stimuli have been used as an experimental non-invasive test stimulus to cause nociception during general anaesthesia. 27 Our study supports the previous finding that a short tetanic stimulus relatively poorly reflects the physiological response caused by a surgical stimulus. 21 It has been presumed that short electrical stimulus elicits mainly cutaneous pain mechanisms, whereas surgical tissue damage also contains deeper components.…”

Heart rate variability does not discriminate between different levels of haemodynamic responsiveness during surgical anaesthesia †

“…Before induction, the patients were randomly assigned to five treatment groups differing in target BIS level, and in remifentanil bolus and infusion rates using a stratified randomization protocol. In Groups 1 -3, a propofol targetcontrolled infusion (Diprifusorw, AstraZeneca, Grafenau, Switzerland) was titrated to achieve a BIS level of 45 (5), whereas in Groups 4 and 5 the target BIS levels were 30 (5) and 60(5), respectively. In Groups 1 -3, remifentanil was administered with an initial bolus of 0.2, 0.4, and 0.8 mg kg 21 immediately followed by an infusion of 0.04, 0.08, and 0.2 mg kg 21 min 21 , respectively.…”

Performance of Surgical Stress Index during Sevoflurane-Fentanyl and Isoflurane-Fentanyl Anesthesia

“…Some electroencephalographic (EEG)-derived parameters, such as Entropy, are suggested to reflect also the nociceptive component of anesthesia [3–5]. Changes in skin conductivity and suppression of photoplethysmographic pulse wave amplitude (PPWA) have also been proposed as indicators of nociception [6, 7]. Recently, Surgical Stress Index (SSI), based on a sum of normalized pulse beat interval (PBI) and PPWA, was introduced for the assessment of surgical stress or nociception [8].…”