预充氧化亚氮/异氟醚低流量吸入麻醉

Low Flow Anesthesia with Primed Nitrous Oxide and Isoflurane

报告预充氧化亚氮(N_2O)/异氟醚低流量吸入麻醉经验。30例ASA Ⅰ～Ⅱ级择期全麻下手术患者接受预充N_2O/异氟醚低流量吸入麻醉。静脉诱导期,以10L/min(N_2O 7.0 L/min,O_2 3.0 L/min)快速向回路内预充以2.0％～2.5％的异氟醚。病人气道接麻醉机后,总气流量改为1.0 L/min(N_2O 700ml/min,O_2 300ml/min)维持15min。15min后,总气流量减至600ml/min(N_2O/O_2各300ml/min),同时给予0.8％～1.2％的异氟醚吸入维持麻醉。结果发现:吸入麻醉后5～8min出现一过性MAP降低、HR增快,仅尚未超出正常范围。从吸入氧分数(FiO_2)、吸入/呼出1/E)气中N_2O、O_2、异氟醚浓度(％)监测结果表明,无缺氧也无CO_2蓄积和麻醉药物过最,从而证明本文提供的低流最吸入麻醉方法安全、简便、易行。

The experience of low flow rate anesthesia with primed nitrous oxide (N2O)and oxygen was reported. Thirty cases of ASA physical status Ⅰ-Ⅱ,who received general anesthesia with primed N2O/ isoflurane during induction were studied. Total gas flow rate of 10L/min was primed into the circuit (N2O 7. 0L/min and O2 3. OL/min)companied with the isoflurane of 2- 0% to 2. 5% during induction and tracheal intubations,then reduced to 1. 0L/min at first 15 mins after the tracheal tube of the patient was connected with the anesthesia machine,ratio of N2O to O2 7/3,companied with the concentration of isoflurane 0. 8%-1. 2%. During maintenance total gas flow was reduced further to 600ml/ min,either N2O or O2 half of the totals,and isoflurane inhaled. MAP decreasing and HR increasing were found in all the cases at the very begining of 5-8 mins after the inhalation anesthesia,but both were under normal conditions. No hypoxia and superanesthetic occurred during the maintenance period.