肥胖对术后患者氧储备的影响  

Effects of Obesity on Postoperative Oxygen Reserve

作　　者：赵鲁燕 蔡宏伟[2] 任飞[2] 郭曲练[2] 

机构地区：[1]山西省三人民医院重症监护科,大同037008 [2]中南大学湘雅医院麻醉科,长沙410008

出　　处：《麻醉与监护论坛》2010年第4期289-290,共2页Forum of Anesthesia and Monitoring

摘　　要：目的：许多研究表明书后患者的氧储备差，肥胖是影响氧储备的一个因素，这个研究通过观察不同体重指数患者，在术后吸100%的氧时，无通气期间耐受缺氧的安全时间，以探讨不同体重指数对禾后患者氧储备的影响。方法：首次行四肢或头颈部择期全麻手术后病人根据体重指数分为三组：A组（BMI≤25kg·m^-2，标准体重）B组（25kg·m^2〈BMI〈30kg·m^2，超重）；C组（BMI；≥30kg·m^2．肥胖）。进入PACU后，接呼吸机（Crager Evitallventilator（德国）行同步间歇指令通气（SIMV）调节吸入氧浓度为100%，潮气董为7-10ml／kg,呼吸频率10—12次／分，呼吸来正庄采用3cmH2O，持续监测心电图及脉搏血氧饱和度；持续监测呼气未二氧化碳分压及呼气末氧浓度。保持呼气末二氧化碳描记图章常及呼吸末二氧化碳分压维持于33-46mmHg之间，通气直到呼气末氧浓度达到稳定。断开呼吸机接头，持续记录氧饱和度的变化，这个研究中反映氧储备的指标为无通气时限。无通气时定义从停止通气开始到血氧饱和度下降至90%时所需的时间。当血氧饱和度下降至90％时接上呼吸机，调节吸入氧浓摩为40％。潮气最为10ml／kg，呼吸频率为12次／分。此前如出现心率。心律．血压的明显变化时则放弃观察。当血氧饱和度上升至96%时，调节潮气量为7—10ml／kg,呼吸频率10—12次／分。病人气道压根据体重指数，最大不超过30cmH2O.结果：B组和C组的无通气时限明显低于A组，C组的无通气时限低于B组，但差异无统计学意义；相关性：无通气时限与体重指数成负相关，Rs=-0.556（P＜0.005）,有统计学意义。三组患者基础平均动脉压和心率无明显差别．在无通气期间心率明显加快．以C组最明显．并且C组平均动脉压显著高于A组，结论：术后患者的氧储备羞，而肥胖进一步减少氯储备．无通气期间心Background：Postoperative patients had less oxygen reserves compared with usual. Obesity is an influencing factor. The research investigated how body mass index（BMI,calculated by weight（kg）/height（m2） affected postoperative patients＇safety margin before pulse oxygen saturation desaturated to 90% when ventilation by 100% oxygen was withheld. Methods： 52 patients are assigned to three groups according to BMI：A group（BMl〈25.0kg/m2,n=17）,B group（25.0 kg/m^2〈BMl〈30 kg/m^2,n=24）,C group（BMI〉30.0 kg/m^2,n=11）.They had been operated through general anaesthesia for elective surgery of extremities. After entering PACU,all patients were mechanically ventilated with SIMV model. I：E ratio on 1：2, tidal volumes of 7-10 ml/kg body weight. PETCO2 was kept at 40±5mmHg by adjusting respiratory frequency. The oxygenation continued until a stable state of end-tidal oxygen concentration is achieved. Ventilation was then withheld until the oxygen saturation, assessed by pulse oximetry, decreased to 90%.The oxygen saturation was continuously registered. The patients were ventilated by adjusted breathing frequency to 12 bpm and vital volume to 10ml per kg. The vital volume was lowered to approximately 7ml/kg body weight and breathing frequency was lowered to approximately 10 bpm to avoid hyperventilation, as soon as SpO2 was raised to 96% and end-tidal carbon dioxide was normalized. Airway pressure did not exceed 30 cm H2O in any patient. Blood samples were taken from dorsal artery of foot for blood-gas analysis. Results： The times of oxygen saturation dropping to 90% were 519±30s, 328±85s, 290±54s corresponding in A group ,B group and C group. Apnoea tolerance in the A group was significantly longer compared with B and C group. Apnoea tolerance in the B group was longer than C group but without statistically significant. Apnoea tolerance was positively correlation with body mass index. MBP in three groups was higher after apnea, which C group was significantly higher. Heart rates in thre

关 键 词：肥胖 氧储备 无通气时限 

分 类 号：R454.1[医药卫生—治疗学]