Laboratory basis for the medical management of necrotizing enterocolitis (NEC)

Necrotizing enterocolitis (NEC) is a serious condition affecting the neonate that may be responsive to medical management. This study evaluates the efficacy of supplemental oxygen (FiO2 40% and 50%), systemic antibiotics (ampicillin and gentamicin, cephamandole) and oral antibiotics (trimethoprimsulfamethoxazole, neomycin and gentamicin) in a weanling rat bowel ischemia model induced by a transient (one minute) occlusion of the superior mesenteric artery. Animals were evaluated for overall survival, duration of survival, presence of bowel necrosis or perforation at seven days. Mortality in ischemic controls was 83.8%. This was reduced to 52% by FiO2 of 50%, and 40% with systemic ampicillin and gentamicin (with or without FiO2 50%) (P<.001). Length of survival was 3.4 days in controls and increased from 5.4 to 5.9 days in rats given FiO2 50% and/or ampicillin and gentamicin (P<.001). The incidence of bowel necrosis in controls was 60% and was reduced to 25% in rats given systemic ampicillin and gentamicin and 23.3% with 50% FiO2 and the same antibiotics (P<.001). Systemic cephamandole and oral antibiotics had no beneficial effects.

坏死性小肠结肠炎（NEC）是一种影响新生儿的严重疾病，可能对医疗处理有反应。本研究在由肠系膜上动脉短暂（1分钟）闭塞诱导的断奶大鼠肠道缺血模型中评估了补充氧气（吸入氧浓度为40%和50%）、全身性抗生素（氨苄西林和庆大霉素、头孢孟多）以及口服抗生素（复方磺胺甲恶唑、新霉素和庆大霉素）的疗效。在7天时对动物的总体存活率、存活时间、肠道坏死或穿孔情况进行评估。缺血对照组的死亡率为83.8%。吸入氧浓度为50%时死亡率降至52%，使用全身性氨苄西林和庆大霉素（无论是否同时给予吸入氧浓度50%）时死亡率降至40%（P<0.001）。对照组的存活时间为3.4天，给予吸入氧浓度50%和/或氨苄西林和庆大霉素的大鼠存活时间从5.4天增加到5.9天（P<0.001）。对照组肠道坏死的发生率为60%，给予全身性氨苄西林和庆大霉素的大鼠以及同时给予吸入氧浓度50%和相同抗生素的大鼠肠道坏死发生率降至25%和23.3%（P<0.001）。全身性头孢孟多和口服抗生素没有有益效果。