The Study Of Gastrointestinal Function Protective Effection And Its Mechanisms Of Early Gastric Infusing Pyruvate Oral Rehydration Solution In Dogs With Burn Shock

Objective：1.To investigate the gastrointestinal function protectiveeffection and its mechansms of early gastrointestinal fluid resuscitation withpyruvate oral rehydration solution and HCO₃-oral rehydration solution on dogswith burn shock.2. Comparing the protective effect of pyruvate oralrehydration solution and HCO₃-oral rehydration solution on gastrointestinalfunction, so as to improve oral rehydration formula and provide experimentalevidence for appling in burn shock resuscitationMethod：Eighteen adult male Beagle dogs burned50%TBSAⅢ°bySolidification gasoline under anesthesia with IV injection of propofol wererandomly divided into three groups: non-resuscitation group （NR）,pyruvate-oral rehydration solution group （Pyr-ORS） and HCO₃-oralrehydration solution group（HCO₃-ORS）. NR group got no fluid resuscitationtreatment; the pyruvate-oral rehydration solution and HCO₃-oral rehydrationsolution were infused into dog’s stomach respectively with a infusion pumpaccording to Parkland formula (4ml·1%TBSA^-1·kg-1)30min after burn.Experimental observation end point was on6hours after burn. we measuredthe following parameters in experimental period:â‘ Arterial blood gas,hemodynamic parameters and blood flow under gastrointestinal mucousmembrane.â‘¡Gastric emptying rate in2hours after burned and the totalamount of intestinal absorption in6hours after burned.â‘¢Gut barrier function（DAO, bowel mucosa permeability） and Na⁺-K⁺-ATPase of intestinal mucosal.â‘£Changing of blood and bowel tissue inflammatory factors （TNF-α, NOS）and oxygen free radical products （XOD, MDA, MPO）.Result： Gastric emptying rate and the total amount of intestinalabsorption in Pyr-ORS group was significantly better than those in HCO₃-ORSgroup （P<0.05）；The level of Na⁺-K⁺-ATPase of intestinal mucosal in bothPyr-ORS group and HCO₃-ORS group were significantly higher than those in NR group.At the same time，The level of Na⁺-K⁺-ATPase of intestinal mucosalin Pyr-ORS group was significantly higher than those in HCO₃-ORS group（P<0.05）; The blood flow of gastrointestinal mucous membrane in NR groupwas significantly lower than those in both Pyr-ORS group andHCO₃-ORSgroup, and the blood flow of intestinal mucous membrane inPyr-ORS group was also significantly higher than those in HCO₃-ORSgroup（P<0.05or P<0.01）. The MAP, CI and dp/dtmaxwere droppedsubstantially and kept in low level continued in NR group, but those in bothPyr-ORS group and HCO₃-ORS group recovered gradually. At6hours afterburned, MAP,CI and dp/dtmaxwere better in Pyr-ORS group than those inHCO₃-ORS group （P<0.05）. The jejunum tissue levels of XOD, MPO, NOS,MDA, the plasma level of TNF-αand the bowel mucosa permeability werelower in Pyr-ORS group than those in HCO₃-ORS group （P<0.05or P<0.01）.Conclusion：1. This study copied amodel of oral fluid resuscitation inBeagle dogs with50%TBSAⅢ°burn shock successfully.2. Pry-ORS canincrease MAP, CI, plasma volume and blood flow of gastrointestinal mucousmembrane significantly, and also improve gastric emptying and intestinalabsorption disorder that resulted from serious burns.3. Pry-ORS can inhibitethe activity of bowel tissue peroxidase and nitric oxide synthase. It can alsoreduce the level of plasma TNF-α and lipid peroxide, and reduce the bowelmucosa damage pruoduced by inflammatory factors and oxygen free radicals.4. Pry-ORS can reduce the activity of plasma DAO, promote proteinexpression of intestinal epithelium tight junction, reduce the permeability ofbowel mucous membrane and protect the intestinal mucous function.5.Compare to WHO recommended HCO₃-ORS, Pry-ORS have better protectiveeffection on gastrointestinal function damage result from tissue ischemia inburn shock.