Carpal ligament decompression under local anaesthesia: the effect of lidocaine warming and alkalinisation on infiltration pain.
ABSTRACT This study investigated the effects of alkalinization and warming of lidocaine 1% on injection pain in patients undergoing carpal tunnel decompression. Sixty-four adult patients were randomly allocated into one of three groups: Group A (n=20) received plain lidocaine 1%, Group B (n=22) alkalinized lidocaine and Group C (n=22) warmed and alkalinized lidocaine. Pain on needle insertion and on infiltration was assessed using a 100mm Visual Analogue Scale (VAS). There was no significant difference regarding pain on needle insertion whereas significant differences were noted in reference to infiltration pain. In Groups B and C (alkalinized lidocaine) the VAS scores on skin infiltration were significantly lower than in Group A, while the pain score in Group C (alkalinized and warmed lidocaine) was significantly lower than in Group B.
Article: Alkalinisation of local anaesthetics prescribed for pain relief after surgical decompression of carpal tunnel syndrome.[show abstract] [hide abstract]
ABSTRACT: To compare the duration of analgesia achieved following administration of buffered prilocaine versus plain prilocaine to patients undergoing surgical decompression of the median nerve. 40 (32 female and 8 male; mean age, 50.5 years) patients who underwent surgical decompression of carpal tunnel syndrome were recruited. Patients were randomly allocated to 2 groups: the alkalinised group was given 10 ml of prilocaine hydrochloride 2% buffered with 1 ml of sodium bicarbonate 8.4%, whereas the non-alkalinised group received 10 ml of plain prilocaine hydrochloride 2% solution. Patients were asked to rate their comfort level at the operation site in the first 6 hours following surgery and after discharge from hospital using a visual analogue scale (VAS). The duration of analgesic effect was evaluated every 3 hours. Additional oral analgesia in the form of paracetamol 500 mg tablets was available to patients if required for break-through pain. Significantly lower VAS scores were reported by the alkalinised group during the first postoperative 12 hours. The change of VAS scores over time was significantly higher in the non-alkalinised group. The mean analgesic requirement for paracetamol tablets in the alkalinised and non-alkalinised groups was 4 and 34, respectively. Buffered prilocaine provided a longer postoperative pain-free period for patients undergoing surgical decompression of the median nerve. It is easy, safe, and cost-effective.Journal of orthopaedic surgery (Hong Kong) 01/2006; 13(3):285-9.