簡易手術之脊椎麻醉使用長效麻醉劑後應勿需置放導尿管

Urinary Catheterization May Not Be Necessary in Minor Surgery under Spinal Anesthesia with Long-acting Local Anesthetics

背景：本前瞻性研究為比較脊椎麻醉所使用之兩種長效局部麻醉劑（0.5％ bupivacaine及tetracaine） ，使用於簡易骨科及一般外科手術，探討其術後尿液滯留的發生機率及導尿管是否應常規置放。方法：以八十位進行簡易手術的年輕病患，隨機分為兩組，於脊椎麻醉時各別給予bupivacaine或tetracaine，記錄脊椎麻醉的最高位置、感覺恢復退至L5的時間、脊椎麻醉後首次自解小便的時間、手術中失血量及靜脈輸液總量等。結果：兩組病患間的性別比例、年齡、身高、體重及手術種類皆無明顯差異。兩組的手術中失血量皆少於100毫升，其靜脈輸液總量均少於800毫升。雖然感覺恢復退至L5的時間上，tetracaine組（259.3 ± 39.6分鐘）明顯較bupivacaine組（225.0 ± 38.6分鐘，P< 0.01）為長，但兩組於脊椎麻醉後首次自解小便的時間並無統計上差異，分別為433.9 ± 89.1及411.0 ± 98.3分鐘（P = 0.286）。兩組皆有一名病患出現尿液滯留的情形，發生率為2.5％，單次導尿後就未再出現尿液滯留的情形。結論：本研究結果顯示年輕病患接受簡易手術，靜脈輸液量不多時，即便在眾多麻醉方法中被認為尿液滯留發生率最高的脊椎麻醉方式，又使用長效局部麻醉劑後，尿液滯留發生率仍偏低，亦不需常規置放留置式導尿管。在考量成本及導尿管併發症的前提下，謹慎注意膀胱腫脹的症狀即可，此研究可望幫助外科醫師消除在脊椎麻醉後擔憂是否應常規置放導尿管的困擾。

Background: This prospective study was designed to compare the incidence of urinary retention after spinal anesthesia between 0.5% hyperbaric bupivacaine and 0.5% hyperbaric tetracaine in patients who underwent minor orthopedic and general surgeries. Methods: Eighty patients aged 18-40 were randomly assigned to receive either hyperbaric bupivacaine or tetracaine for spinal anesthesia. Intravenous fluids were administered for maintenance of basal requirement, replacement of blood loss and prevention of hypotension. The highest level of analgesia, regression time of sensory block to L5 level, length of time from spinal injection to spontaneous urinary voidance, and volume of perioperative fluid administered were recorded. Results: Of the 80 patients who received either hernioplasty, fistulectomy, hemorroidectomy or orthopedic surgery, two were catheterized (2.5%) because of urinary retention. They were administered less than 800 mL of fluid intraoperatively. Intraoperative blood loss was less than 100 mL in all cases. There were no statistical differences in demographic data, types of surgery, sensory blockade and perioperative fluid administration between the two groups. Although the regression time of sensory blockade with tetracaine (means ± SD, 259.3 ± 39.6 min) was significantly longer than that of bupivacaine (225.0 ± 38.6 min, P < 0.01), the time elapsing from the spinal injection to the first spontaneously voiding after surgery did not show statistical difference between two groups (433.9 ± 89.1 vs. 411.0 ± 98.3 min, P = 0.286). Conclusions: Our results show that, in younger surgical patients who did not receive large amount of fluid intraoperatively, the incidence of urinary retention was low, although prolonged sensory blockade by both long-acting local anesthetics was evident. Thus, urinary catheterization should not be a routine must for every patient undergoing minor surgery with long-acting spinal local anesthetics. From the viewpoint of financial expense, avoidance of complication and annoyance of urinary catheterization, careful observation of urinary bladder fullness in the form of lower abdominal distension, discomfort, bradycardia, or vomiting after surgery is superior to routine retention urinary catheterization just for ease with work in younger patients undergoing minor surgery under longacting spinal local anesthetics.