The relation between skin temperature increase and sensory block height in spinal anaesthesia using infrared thermography

Abstract

The varying baseline temperatures across the trunk, the limited sympathetic block-induced increase in skin temperature at the trunk and the difficult control of influences from the surroundings partly obscured the extent of the skin temperature increase and its correlation to sensory block height. These factors have to be controlled to improve the use of infrared cameras as an easy bedside tool for predicting the cranial extent of (sympathetic blockade during) spinal anaesthesia.

Skin temperature measured by infrared thermography after ultrasound‐guided blockade of the sciatic nerve

“…More proximal skin temperatures, as those on the lateral side of the knee, do not change significantly. The same phenomenon can be seen with neuraxial blocks, where almost no temperature rise occurs on the abdomen and proximal parts of the legs …”

Cutaneous innervation of the hand: clinical testing in volunteers shows high intra- and inter-individual variability

“…11e13 Alternative methods, such as evaluation of skin temperature (which is also a factor of skin sensitivity), were not performed because of conflicting results in the literature and various factors influencing the measurements. 14 In addition, the sympathetic portion of the three investigated nerves is not described (different to, e.g. the sciatic nerve, where a large portion of sympathetic fibres can be assumed 15 ) and may differ between the three nerves.…”

Evaluation of the success of sciatic nerve blockade by skin temperature measurement through infrared thermography

“…The same phenomenon can be seen with neuraxial blocks, were almost no temperature rise occurs on the abdomen and proximal parts of the legs. [9] In all cases, temperature rise precedes a negative pinprick, in slow as well as in fast arising blockades. This seems in accordance with the differences in speed of blockade of nerve fibers involved in this process, the fast blockade being in sympathetic C-fibers (with consequent temperature rise) compared to the slower blockade of the A-δ-fibers (with consequent fading of sensitivity for temperature and pain).…”