The Effects Of Enteral Carbachol Plus Oral Rehydration Salt On Gastric Emptying In The Treatment Of Early Shock In Scalded Rats

Objective1. To define the dosage of carbachol in oral resuscitation with oral rehydration salt(ORS) by investigating carbachol on gastric emptying rate and gastric blood flow in early shock stage of scalded rats.2. To investigate the effects of enteral carbachol plus ORS orally on function of gastric emptying in early shock stage of scald rats by assaying gastric emptying rate and determining some elements that can affect function of gastric emptying,such as gastric blood flow,plasma motilin,the activity of ATPase and NOS in gastric tissue and the content of NO in the gastric tissue.MethodsExperiment 1: Male wistar rats were randomly divided into shame control groups,scalded group and enteral carbachol group. About 30%TBSA of scalded injury on back of rats were induced with boiling water(100 ,15s) in all groups except the shame control group.Phenol red were taken orally after making modol of rats, carbachol of different dosage (20 ug/kg, 40ug/kg, 60ug/kg, 80ug/kg, 100 ug/kg, 120 ug/kg) was infused by an oral tube about thirty minutes after scalded. All rats were sacrificed at two hours post scalded to calculate the gastric emptying rate and determine the gastric blood flow.Experiment 2: The wistar rats were randomly divided into five groups: shame control, scalded without fluid resuscitation ,scalded resuscitation with oral rehydration salt, scalded resuscitation with the enteral carbachol, scalded resuscitation with enteral carbachol plus ORS group. Rats inflicted with 30 % TBSA degree full-thickness scalded injury on back. the phenol red was taken as the indicator to assay the gastric emptying rate. In all groups except the shamecontrol.ORS was given by oral tube according to semi-dosage of Parkland' formula ( 4ml.kg^-1.1%TBSA ) at 30 min postinjury, and the dosage of carbachol was 60/kg.w . The rats were sacrificed at 2h,4h,6h post scalded to determine the gastric emptying rate after gastric blood flow was determined and to assay the value of plasma motilin, the activity of ATPase and NOS in gastric tissue and the content of NO in the gastric tussue. Result1. The gastric emptying rate and the gastric blood flow decreased apparently after scalded,which were promoted by carbachol of the defferent dosage taken orally and with 60ug/kg as the best dosage.2. In early shock stage after scalded, The gastric emptying rate, gastric blood flow and plasma motilin significantly decreased (p<0.01),activity of ATPase in gastric tissue significantly descented ,the content of NO and activity of NOS in gastric tissue increased apparently, which they were progressed by the deferent oral resuscitation at deferent degree ,but action of the carbachol plus ORS was notible.ConclusionCarbachol of proper dosage plus ORS in oral resuscitation can improve the function of gastric emptying and gastric blood flow, promote motility of gastrointestinal tract in early shock stage in scalded rats,and improve therapeutic effect of ORS in the resuscitation of burns shock, and can reduce the quantity of ORS at some degree.