内镜下甲状腺切除术中高碳酸血症的预防

Prevention of hypercarbia during endoscopic thyroidectomy

目的 :探索防止内镜下甲状腺切除术中出现高碳酸血症的方法。方法 :用皮下扩张器在胸前区和双侧颈阔肌分离皮肤与皮下组织 ,以 5 mm Hg(1mm Hg=0 .133k Pa)的 CO2 充气压力维持外科操作空间 ,共实施内镜下单侧单纯性甲状腺腺瘤切除术 8例。 结果 :CO2 充气时间为 (99.6 3± 19.34) m in,分钟通气量维持在 12 0 m l/ (kg· min) ;CO2 充气期间 ,动脉血 CO2分压 (Pa CO2 )无明显上升 ,平均为 (33.19± 2 .15 ) mm Hg,呼气末 CO2 分压 (PETCO2 )为 (2 9.0 6± 1.5 5 ) mm Hg,Pa CO2 和PETCO2 的差值为 (4.0 9± 1.79) mm Hg。结论 :采用 5 m m Hg的 CO2 充气压力 ,在正常的分钟通气量下便可维持正常的 CO2 分压 ,避免了因手术区域组织明显的 CO2 吸收而导致的高碳酸血症的发生 ,同时又能保持足够大的手术操作空间。

Objective:To prevent severe hypercarbia during endoscopic thyroidectomy. Methods:Eight patients(ASAⅠ Ⅱ) underwent selective endoscopic thyroidectomy for benign thyroid adenoma were included. A long subcutaneous dissector was applied to create a subcutaneous space in the precordial area and the platysmal area, CO 2 was insufflated to the space at a pressure of 5 mmHg. Then endoscopic thyroidectomy was performed. Results:The duration of CO 2 insufflation was (99.63±19.34) min;Minute ventilation was 120 ml·kg -1 ·min -1 .PaCO 2 gradually increased during CO 2 insufflation,and the average PaCO 2 was (33.19±2.15) mmHg.The P ET CO 2 was (29.06±1.55) mmHg and PaCO 2-P ET CO 2 gradient was (4.09±1.79) mmHg. Conclusion:The insufflation pressure of 5 mmHg is high enough to maintain the surgical space and low enough to avoid significant hypercarbia. When the insufflation pressure is down to 5 mmHg, normal minute ventilation is sufficient to maintain normocarbia.