Rebreathing and anaesthetic type oxygen masks Partial rebreathing masks incorporating non-rebreathing valves and reservoir bags are not in common use but can provide concentrations greater than 60% at low oxygen flow rates. In cardiac or respiratory arrest, tight fitting anaesthetic-type masks can achieve 100% oxygen, but prolonged use risks oxygen toxicity and reabsorption atelectasis.
Non-rebreathing mask
FiO2: 80%~90% ; O2: set to prevent collapse of bag
優點
可提供超過80%的氧 氣 有一單向瓣膜防止 吐出之空氣混入
缺點
面罩太緊會不舒服 患者產生恐怖感 妨礙進食吐痰 眼睛乾燥與刺激 易造成二氧化碳滯留
1、流量是0.5~1升/分,湿化瓶内气泡连续 出现,但听不到气泡破裂声。 2、流量是1~2升/分,气泡连续出现加快。 3、流量是3~5升/分,水面沸腾,离1米便可 听到气泡破裂声。
Nasal Cannula
FiO2= 20% + O2 L/min (1~6 L/min) × 4%
優點
可加熱加濕
低流量面罩 Typical low flow mask. This mask is ideal for providing high concentrations of oxygen (40-60%). The flow rate of oxygen required to achieve an approximate FiO2 is shown on the mask packaging