Donaldson L L, Trostle S S, White N A
Marion duPont Scott Equine Medical Center, Virginia-Maryland, Regional College of Veterinary Medicine, Leesburg 20177, USA.
Equine Vet J. 1998 Mar;30(2):144-51. doi: 10.1111/j.2042-3306.1998.tb04474.x.
The use of laparoscopy for the diagnosis or therapeutic management of abdominal disease in the horse has distinct advantages when it allows the horse to remain standing. However, distending the abdomen by insufflation of a biologically active gas in an anaesthetised horse may add to the physiological challenge of general anaesthesia and recumbency. The cardiopulmonary responses to abdominal insufflation with carbon dioxide (CO2) to 15 mmHg pressure were evaluated in 6 horses in dorsal recumbency anaesthetised with halothane in oxygen and subjected to laparoscopic colopexy. Vaporiser settings targeted a fractional expired halothane of 1.5 MAC and a clinically acceptable depth of anaesthesia. Pressure and rate controlled positive pressure ventilation was adjusted to an ETCO2 of 35 mmHg before abdominal insufflation and was not changed thereafter. Cardiopulmonary data were collected before, at 30 and 60 min during and 30 min after CO2 insufflation. ANOVA for repeated measures followed by Tukey's protected t test were used to determine differences. Partial pressure of oxygen and pH of arterial blood, tidal volume and systemic vascular resistance decreased during abdominal insufflation and laparoscopic surgery whereas mean arterial blood pressure, right atrial pressure, cardiac index, stroke index, partial pressure of CO2 in arterial blood and end tidal respiratory gases, and calculated physiological shunt increased significantly. Only systemic vascular resistance returned to the pre-insufflation level after desufflation. The hypercapnia, acidosis and apparent increase in cardiac work that accompany CO2 pneumoperitoneum for laparoscopic surgery could place the anaesthetised horse at additional risk of perioperative complications.
在马站立状态下使用腹腔镜诊断或治疗腹部疾病具有明显优势。然而，在麻醉的马体内注入生物活性气体使腹部膨胀，可能会增加全身麻醉和卧地带来的生理挑战。对6匹在氧气中用氟烷麻醉并处于背卧位接受腹腔镜结肠固定术的马，评估了二氧化碳（CO₂）充气至15 mmHg压力时腹部充气对心肺的影响。蒸发器设置目标是使呼出的氟烷分数达到1.5 MAC以及达到临床上可接受的麻醉深度。在腹部充气前将压力和速率控制的正压通气调整至呼气末二氧化碳分压（ETCO₂）为35 mmHg，此后不再改变。在CO₂充气前、充气期间30分钟和60分钟以及充气后30分钟收集心肺数据。采用重复测量方差分析，随后进行Tukey's保护t检验以确定差异。腹部充气和腹腔镜手术期间，动脉血氧分压和pH值、潮气量及全身血管阻力下降，而平均动脉血压、右心房压力、心脏指数、每搏指数、动脉血二氧化碳分压及呼气末呼吸气体、计算得出的生理分流显著增加。放气后只有全身血管阻力恢复到充气前水平。腹腔镜手术中CO₂气腹伴随的高碳酸血症、酸中毒以及心脏做功明显增加，可能会使麻醉的马面临额外的围手术期并发症风险。
