Traumatic Shock in Mice

Abstract

A standardized burn or tourniquet shock was employed, 95-100% fatal in untreated mice. Therapy consisted of 1 ml./20 g. body wt. admd. 1 hr. after trauma in a single dose or 4 divided doses at 2-hr. intervals. The following intraven. fluids were employed: mouse whole blood or plasma, human serum albumin in glucose or 0.9% NaCl, or saline alone. One group received saline orally; controls received no treatment. Bleeding volume, hematocrit, plasma proteins, and rectal temp. were detd. at 0.25, 2, 4, 6.5 and 22 hrs. after therapy. At 0.25 hr. admd. colloids restored bleeding volumes to normal values while oral and intraven. saline had little or no effect. Corresponding effects on hematocrits occurred, with the exception of whole blood therapy. Plasma proteins from 0.25-6.5 hrs. were above normal in all groups except saline intraven. or orally, where decreases occurred throughout the expt. Within 2 hrs. after therapy the effects of plasma and albumin on bleeding vol. and hematocrit had decreased to the point where no differences between electrolyte and colloid therapy were present. With whole blood the bleeding vol. remained slightly higher and hematocrits remained near 85% for more than 7 hrs. Albumin in glucose approached values of untreated controls. Rectal temps. fell progressively, except for transitory rises coinciding with bleeding vol. increases. In the comparison of divided doses of plasma and saline, saline was admd. in a 50% greater vol. with each injn. to achieve survival responses similar to plasma. In general the above detns. indicated that the response of burned mice to divided-dose therapy was similar to single-dose therapy. Mortality studies showed plasma, whole blood, saline intraven. and orally, and albumin in saline equally effective; albumin in glucose was without effect. Thus, certain acute hemodynamic responses to therapy may be unreliable as criteria of therapeutic effectiveness. Following single intraven. injn. of plasma or saline, distr. of the fluid in the shocked mouse was measured. Within an hr. nearly all the fluid was recovered in the injured areas except for that part which corrected dehydration in the uninjured tissues. The rate of local accumulation following plasma was indistinguishable from that of saline.