胃肠道左旋精氨酸营养干预对严重烧伤患者休克期复苏的影响

目的观察严重烧伤患者休克期经胃肠道给予左旋(L)精氨酸对休克复苏的影响,探讨其机制。方法选取烧伤面积≥30%TBSA的患者20例,并随机分为:L-精氨酸组,伤后24h内开始从鼻肠管给予L-精氨酸;对照组,伤后24h内开始从鼻肠管给予50g/L葡萄糖盐水500ml/d,连续4d,每组10例。在伤后1、2、3、4d分别抽取两组患者静脉血,检测其血清超氧化物歧化酶(SOD)活性及丙二醛(MDA)和一氧化氮(NO)含量,并抽取患者动脉血检测其乳酸含量。结果L-精氨酸组患者SOD活性在伤后呈上升趋势,于伤后4d达峰值(68±23)U/ml,与对照组(31±9)U/ml比较,差异有统计学意义(P<0·01)。两组患者伤后MDA、NO含量均呈下降趋势,伤后2dL-精氨酸组NO(50±14)μmol/L]下降最明显,与对照组(78±22)μmol/L比较,差异有统计学意义(P<0.01)。伤后4d两组患者MDA下降最明显(3.4±0.8)、(3.5±1.3)μmol/L],L-精氨酸组血乳酸含量在伤后2、3d显著低于对照组(P<0.05或0.01)。结论严重烧伤患者休克期经胃肠道给予L-精氨酸可抑制其体内NO含量过度升高,使血乳酸含量降低,血清SOD活性增加,改善组织脏器血流灌注及氧合状态,减轻缺血再灌注损伤,有利于预防隐性休克的发生或减轻其损害。

Influence of the enteral feeding of levorotatory arginine on severely burned patients during shock stage

OBJECTIVE: To investigate the effects and the mechanism of action of postburn dietary supplementation of levorotatory arginine (L-Arg) on burn shock resuscitation in severely burned patients. METHODS: This study was designed to be a prospective, randomized, single blinded and controlled one. Twenty burn patients with total burn surface area (TBSA) more than 30% were enrolled and randomized into two groups; 1) Group A (n = 10): enteral feeding of 50 g/L glucose normal saline (GNS) 500 ml per day containing L-Arg (400 mg/kg.day) at equal pace with fluid infusion for shock resuscitation for 4 days. 2) Group C (n = 10): enteral feeding with only 50 g/L GNS 500 ml per day for 4 days. All of the twenty patients received equal amount of enteral feeding via an intra-gastric tube with the aid of an enteral feeding pump, started within 24 postburn hours (PBH). Venous blood was harvested from all the patients in both groups on 1, 2, 3 and 4 postburn day (PBD) for the determination of serum content of nitric oxide (NO), malondialdehyde (MDA) and the activity of serum superoxide dismutase (SOD). And the arterial content of lactate (BL) was also determined concomitantly. RESULTS: The results indicated that the serum SOD activity in group A was increased after burns, peaked on 4 PBD (68 +/- 23 U/ml), and it was obviously higher than that in group C (31 +/- 9 U/ml, P < 0.01). The serum contents of MDA and NO were decreased in both groups after burns. On 2 PBD, the serum NO level in group A decreased to the lowest level (50 +/- 14 micromol/L), which was obviously lower compared with group C (78 +/- 22 micromol/L, P < 0.01). On 4 PBD, serum MDA levels in group A (3.4 +/- 0.8 micromol/L) and group C (3.5 +/- 1.3 micromol/L) were decreased to the lowest level. The BL content in group A was obviously lower than that in group C on 2 and 3 PBD (P < 0.05 or 0.01). CONCLUSION: Enteral supplementation of L-arginine can decrease excessive NO production to a relatively normal level, and it might be beneficial to resuscitation of burn shock. It might also exert a protective effect against ischemia/reperfusion injury to burn patients.