脊髓麻醉般是以腰椎穿刺法進行注射，接受此類手術的病人，頭痛為其術後常見副作用之，常規術後平躺8小時的臥床休息，為國內主要的頭痛預防法，但病人常不耐久躺且其預防效果並不明確。本文以實證醫學觀點為基礎，探討脊髓麻醉術後常規平躺8小時以預防頭痛之合理性。並以PICO的架構將問題勾勒出來，進行文獻搜尋與評讀及結果討論。根據文獻提供的證據顯示躺床時間長短似乎與頭痛發生機率無顯著相關性，甚至可鼓勵病人提早下床活動，有助於降低頭痛發生率，為改善臨床措施多添幾分支持度。

Spinal anaesthesia is a kind of regional anesthesia by lumbar puncture. After lumbar puncture, headache is one of the most common complications. Therefore, the patient is commanded to take the eight-hour bed rest to prevent headache after procedure. However, the effect of bed rest is still unclear. On the other hand, longer bed rest is uncomfortable for patient. Accordingly, it is required to review the available evidence to rationalize that bed rest for eight hours is effective to prevent headache after spinal anesthesia. We use the method of Evidence-Based Medicine including asking, acquiring, appraising, applying and auditing to look for a valid paper to support the benefit of bed rest. In the systemic reviews we found, no evidence in the trial has been shown that longer bed rest is significantly to decrease risk of headache. In fact, some evidence support that early mobilization after procedure could decrease risk of headache. Overall, these proofs support us to improve clinical care.