台灣硬膜外麻醉之學習曲線與建議執行例數之探討

The construction of learning curve and recommended case load for training of epidural anesthesia in Taiwanese patients

硬膜外麻醉為諸多麻醉技術中被報告為最困難之一，由於我們以硬膜外阻斷術作為麻醉或止痛的病患數相當多﹔因此設計此研究來建立學習曲線與探討技術成熟所須之執行例數。評估400人次由4位第一年住院醫師所執行之腰椎硬膜外麻醉，病患選擇為以脊椎骨突起分級屬第一與第二級之病例。所有的硬膜外麻醉均以標準程序，記錄每位住院醫師執行前100例硬膜外麻醉的下列資料：第一個腰椎定位節的置管成功率、嘗試次數（皮膚穿刺孔數）、消耗時間（由局部麻醉至硬膜外量管完成）。分析資料以評估硬膜外阻斷術之學習曲線及訓練需要例數。探討的結果是在執行三十例硬膜外麻醉之後，第一次量管成功率可穩定維持在90%附近。完成三十例硬膜外麻醉前後之第一次量管成功率分別為：72.57%與91.1%σ＜0.001）：而其他評估硬膜外阻斷術之成效指標如下：完成三十例硬膜外阻斷術前後之嘗試次數分別為1.26（95%信賴區間CI：1.18-1.34）與1.14（95%信賴區問：1.09-1.17）（P<0.05）﹔而執行平均消耗時間（標準差）分別為8.98（±0.89）與6.12（±1.21）分鐘（P<0.001）。因此，我們對硬膜外麻醉的建議訓練執行數量為至少三十例，訓練之住院醫師執行超過30例硬膜外麻醉之後，技術上便可驅於穩定。

Epidural anesthesia was reported to be the most difficult manual anesthetic procedures. There are a great amount of patients received epidural blocks for analgesia or anesthesia in our hospital; hence, we designed this study to construct learning curve for epidural block and investigate case load adequate to achieve acceptable maturity of this procedure.Our study was designed to evaluate 400 lumbar epidurals performed by 4 first-year residents. The study enrolled 400 cases classified as grade 1 and 2 of spinal process landmarks. We documented the first 100 performed epidural anesthesia for each resident. For each procedure, following data were recorded and analyzed to construct learning curve and evaluate case load for training, including first-level successful rate for catheter indwelling, trying attempts and consumption time. First level success rate maintained around 90% after thirty procedures of epidural anesthesia. Mean success rate before and after thirty procedures of epidural anesthesia were 72.57 % and 91.1 % respectively (P<0.001). The mean trying attempts were 1.26 (95% CI: 1.18-1.34) and 1.14 (95% CI: 1.09-1.17) for epidural anesthesia before and after 30 procedures respectively (P<0.05). The mean (SD) consumption time were 8.98 (0.89) and 6.12 (1.21) minutes for epidural anesthesia before and after 30 procedures respectively (P<0.001). We concluded that after practice more than thirty cases of epidural anesthesia residents can achieve maturity of the most difficult manual anesthesiological skill in our institution. Our recommended case load for training of epidural anesthesia was thirty at least.