Cryoanalgesia

Abstract

SummaryThe introduction of cryoanalgesia has reawakened interest in the therapeutic use of cold as a means of producingpain relief: The historical background to both local cooling and nerve freezing is recorded and the advances since the introduction of cryoprobes in 1961 are described. The possible mechanisms of freeze damage, the physical changes occurring in tissues as a result of ice crystal formation and the influence of the probe design on the size of individual cryolesions are all discussed. Gas expansion cryoprobes are described and the application of nerve freezing in the control of both post operative and chronic pain reported. Key wordsPain. Analgesia; cryotherapy.The analgesic effect of low temperature has been known to man since earliest times. Hippocrates (460-377 BC)' left the first written record of the use of ice and snow packs as a local pain-relieving technique when applied before surgery, and similar reports can be traced through history. Such early physicians as Avicenna of Persia (980-1070 AD)^ and Severino of Naples (1580-1656)3 recorded their use of cold for pre-operative analgesia. Later on, the military surgeon Dominique Jean LarrC described his experience of operating, in ambient temperatures of -1 9 T , during the retreat from Moscow in 1812.4 He was amazed to find that painless amputations could be performed on the half-frozen soldiers of Napoleon's army. Simple cooling was still in use during limb surgery as recently as 1941, and the technique, consisting of local ice packs placed around the limb, proved effective even if time-consuming.'Probably the greatest pioneer of local cooling was James Arnott (1797-1883). He devoted the last 50 years of his life to its advancement and to a campaign against the dangers of inhalational anaesthesia.6 Arnott described the use of cold for such varied conditions as headache, erysipelas and other cutaneous and neuralgic affections.' He was the first to recognise the value of cold in the treatment of cancer and in a long treatise on the subject he stated: 'Z shall show by the reports of cases of cancer treated by an anaesthetic temperature that it furnishes us with a perfect means of relieving the pain of that dreadful disease, without producing the stupefaction and disturbance of the system which attends the use of narcotics. . . and holds out greater promise of proving permanently curative than any means hitherto brought forward'.8 His apparatus, a soft cushion through which chilled fluids were passed, was applied over the painful area.

Coding and Plasticity in the Mammalian Thermosensory System

“…A remarkable feature of ongoing pain following burn is that it can be significantly alleviated by cooling; this is one of the oldest known analgesic therapies (Evans, 1981). This effect has been suggested to rely primarily on central inhibition of pain by stimulation of cold sensing neurons(Proudfoot et al, 2006).…”

Ice Reduces Needle-Stick Pain Associated With Local Anesthetic Injection

“…It reduces inflammation and swelling, which facilitates cell oxygenation (14, 15, 18, 20, 23, 26). Cryotherapy also slows the cellular metabolic rate, thereby reducing oxygen demand in an environment of reduced oxygen accessibility (14, 15), and limits the production of tissue-damaging free radicals via suppression of exotoxins.…”

“…Additionally, cryotherapy can prevent neural plasticity and chronic pain by decreasing free nerve ending sensitivity, increasing nerve firing thresholds, and slowing synaptic activity (23, 26, 27). These neural effects increase the patient’s pain threshold and can diminish the need for pharmacologic interventions, such as narcotics or local anesthetics (18, 19, 27). While only a few studies have focused solely on the effect of cryotherapy on abdominal incisions, there is also a paucity of randomized controlled trials.…”

“…It has been used in sports medicine to relieve pain caused by soft tissue injuries due to the relatively small number of side effects (7, 16, 19, 21, 22, 24). Cryotherapy can also be used to reduce postoperative pain (13, 18, 20, 25, 26). …”

Clinical benefits of early cold therapy in accident and emergency following ankle sprain.

“…Its use appears to have been documented first by Hippocrates (460-377 BC), who described its pain-relieving effects (Hippocrates, 1931 translated by W. H. S. Jones). This analgesic effect has since been well documented (Evans, 1981). Other effects are less clear.…”