Evaluation of intercostal cryoanalgesia versus conventional analgesia in postthoracotomy pain.

The objective of the study was to evaluate the effects of cryoanalgesia in patients undergoing posterolateral thoracotomy. A double-blind randomized and prospective study was performed in 100 patients undergoing thoracotomy. They were randomized into two groups: Group A, 55 patients, who had undergone an intercostal cryoanalgesia and group B, control, 45 patients treated only with pharmacological analgesia ad libitum. In both groups we assessed pain in the first 7 postsurgical days, the amount of analgesia required, electromyography of the intercostal muscles involved and recording of maximal static respiratory pressures. Postsurgical pain was significantly lower (p < 0.001) in group A. No patient in group A needed major analgesia and the amount of aminopyrines required was significantly lower (p < 0.001) than those used in group B. Maximal static inspiratory pressure (PImax) showed no significant changes and no significant differences were found between the two groups. Maximal static expiratory pressure (PEmax) significantly decreased (p < 0.001) in the 1st and 2nd week and it was not related to the type of analgesia used. We advocate the use of cryoanalgesia since it significantly reduces pain as well as the doses of analgesia.