卡巴胆碱改善犬50%TBSA烧伤胃内补液时氧动力学指标

目的:研究卡巴胆碱(CAR)对50%TBSA烧伤休克期胃内补液时氧动力学指标的影响。方法:成年雄性Beagle犬12只,先期无菌手术行颈动、静脉置管和肠造口术,24h后用凝固汽油燃烧法造成50%体表面积Ⅲ度烧伤。随机分为2组(n=6):胃内补液组和胃内补液+CAR组。伤后第一个24h从胃内分别输注葡萄糖-电解质溶液(GES)和含CAR的GES液(20μg/kgCAR溶于GES);伤后24h起实施静脉延迟补液,补液量和速率均根据Park-land公式确定。测定动物非麻醉状态下的平均动脉压(MAP)、肠粘膜血流量(IMBF)和血乳酸(LAC)含量,通过血气分析测定动、静脉氧分压和血氧含量、计算氧供量(DO2)、氧耗量(VO2)和氧摄取(Oext),并统计动物72h死亡数。结果:两组犬MAP和IMBF伤后均显著降低,LAC显著升高;伤后72hMAP回升至0h水平,但IMBF和LAC仍低于或高于0h水平。伤后2h胃内补液+CAR组MAP显著高于胃内补液组(P0.01),但之后两组MAP水平无统计学差别。胃内补液/CAR组IMBF伤后高于胃内补液组,伤后8h起LAC也显著低于胃内补液组(P0.05或P0.01)。伤后两组犬DO、VO2和Oext水平较伤前均显著降低(P0.01),伤后72hDO2恢复至0h水平,但VO2和Oext仍显著低于0h。胃内补液/CAR组DO2、VO2和Oext水平伤后8h起始终高于胃内补液组(P0.05或P0.01)。伤后72h胃内补液组死亡数为3/6,胃内补液/CAR为2/6。结论:50%TBSA烧伤胃内补液时加入卡巴胆碱能显著改善氧动力学指标,降低高乳酸血症,提高口服液体复苏的疗效。

Carbachol improve oxygen dynamic parameters during orally fluid resuscitation of a 50% TBSA full-thickness burn in dogs

Objective：To investigate the effect of carbachol（CAR） on oxygen dynamic parameters and hyperlactacidemia during oral fluid resuscitation of burn shock.Methods：Twelve male Beagle dogs were surgically prepared for cannulation of carotid and jugular vein,and enterostomy,24 hours later they were subjected to a 50%（total body surface area,TBSA） full-thickness flame injury under a 10～15 minute anesthesia by IV injection of propofol.The dogs were randomized to gastric fluid infusion group（GI group）and gastric fluid infusion plus CAR group （GI＋CAR）.Either a glucose-electrolyte solution（GES） or GES containing CAR （20 μg/kg） were intragastricly given to animals in GI group or GI＋CAR groups.The delivery rate and volume of GES was in accordance with that of Parkland formula.Mean arterial pressure（MAP）,intestinal mucosal blood flow（IMBF） and blood lactic acid were determined,and blood gas analysis evaluated for oxygen delivery（DO2）,oxygen consumption（VO2） and oxygen uptake（O2ext） at 0,2,4,8,24,48 and 72 hours after injury.Results：The levels of MAP and IMBF markedly reduced,and LAC obviously increased in both groups after burn.MAP returned to 0 h level at 72 h post burn,while IMBF,and LAC were still higher or lower than 0 h levels.The level of MAP of GI＋CAR group was significantly higher than that of GI group at 2 h,and those showed no significant differences between two groups after then.Carbochol administration led to a markedly higher levels of IMBF,and significant lower levels of LAC from 8 h after burn compared with those of GI group（P0.05 or P0.01）.The levels of DO2 VO2 and Oext were reduced markedly after burn in both groups.At 72 h after burn,DO2 returned to 0 h level;while VO2 and Oext though still much lower than 0 h levels.The level of DO2.VO2 and Oext of GI＋CAR group were significantly higher than those of GI group from 8 h after burn（P0.05 or P0.01）.Three of six animals died in GI＋CAR group,which was lower than two of six in GI group.Conclusion：The results indicates that carbachol promotes intragastric fluid resuscitative effect of burn shock by increasing oxygen delivery and decreasing hyperlactacidemia.