Prevention of phantom sensations after spinal anesthesia.

ABSTRACT

BACKGROUND AND OBJECTIVES: Phantom limb sensation (PLS) after the spinal anesthesia is an unpleasant experience. The occurrence rate was 80 to 83 per cent from previous studies. The purpose of this study is to evaluate the incidence of PLS, comparing between placing the lower limbs in the neutral position when analgesic level reach L1 dermatome (L1 group) and T6 dermatome (T6 group). METHODS: Ninety ASA physical status I-II patients, 19-50 year of age, scheduled for lower abdominal surgery under spinal anesthesia were enrolled. Immediately after the spinal injection, the patients were placed supine with one of lower limbs flexed (both hip and knee) and the other kept straight in the neutral position. The analgesic levels were checked every minute; the flexed limbs were turned to the neutral position when the analgesic level reached L1 and T6, the L1 group and the T6 group respectively. The images of the lower limbs and patients' satisfactions were evaluated 15 minutes after the blockage. RESULTS: Twenty per cent of the patients in the L1 group experienced PLS of the flexed limbs while 82.2 per cent of the patients in the T6 group did (P<0.05). None of the patients in the L1 group felt unsatisfied with PLS, on the other hand, 11.1 per cent of the patients in the T6 group expressed their dissatisfaction and would like to have their limbs extended. CONCLUSIONS: This study revealed that by placing the lower limbs in the neutral position immediately after the spinal injection, before the unwanted positions are memorized, could effectively minimize phantom limb sensation after spinal anesthesia.