Heart rate variability analysis for arterial hypertension etiological diagnosis during surgical procedures under tourniquet

Abstract

Pneumatic tourniquets are widely used to provide a bloodless operative field during upper or lower limb surgery. If tourniquet inflation during general anesthesia is initially a mild stimulus, a long duration of inflation can imply heart rate and blood pressure increasing. However, heart rate or blood pressure increasing can also be caused by other external stimuli. Indeed, in the case of an insufficient analgesia, painful surgical stimuli can also cause an increase in heart rate and blood pressure. Therefore, in the case of the use of a tourniquet during surgery, it's very difficult for the anesthesiologist to distinguish hypertension caused by pain from hypertension caused by tourniquet inflation. In such a case, an efficient and reliable hypertension diagnosis could help the anesthesiologist in the medication choice. We have previously developed and evaluated an Analgesia / Nociception Index (ANI) based on the magnitude analysis of the respiratory patterns on the RR series. We hypothesize that the use of such an index could help in the arterial hypertension etiological diagnosis during surgical procedures under tourniquet.

Analgesia nociception index: evaluation as a new parameter for acute postoperative pain

“…The ANI has been shown to potentially be of value in predicting an imminent haemodynamic stress reaction, 6 and it has also been described to predict treatment success for tourniquet-related hypertension. 10 Under general anaesthesia with desflurane and remifentanil, ANI was found to be more reactive than skin conductance monitoring to different levels of remifentanil infusions in children. 11 The latter suggests that different monitors are not simply exchangeable, even though they may also be based on the assessment of autonomic responses to acute pain/nociception.…”

Automated system for measuring integral pain index of patients during general anesthesia

“…The main drawback of methods "2" and "3" is the use of data only from the sympathetic component of the ANS, which is also influenced by other physiological factors [18,26].…”

Automated analgesic drugs delivery guided by vagal tone evaluation: Interest of the Analgesia Nociception Index (ANI)

“…The ANI ability for the analgesia / nociception balance evaluation has been established during a large number of clinical validations [9,11,12,13] which showed that the index was able to detect noxious stimulus with increase sensitivity and specificity than usual clinical parameters (Arterial Blood Pressure and Heart Rate). Furthermore, we showed that, in case of insufficient analgesia, ANI decreases 10 minutes before the occurrence of hemodynamic impairment [13,14].…”