Hypertonic saline-dextran

However, in the horse, the administration of a highly concentrated formula of hypertonic saline-dextran 70 resulted in clinically apparent intravascular hemolysis and hemoglobinuria (Moon et al 1991). Whether less-concentrated formulas are suitable for the horse remains to be investigated. The combination of an alternative colloid, hetastarch (lOml/kg), and hypertonic saline (4 ml/kg) may be an appropriate solution for the resuscitation of horses that are both hypovolemic and dehydrated. Clinical experience suggests that hypertonic-saline-hetastarch is particularly useful in horses with marked hypovolemia and hypoproteinemia, such as those with severe colitis, but this has not been formally evaluated in experimental studies or clinical cases. 

Constable P D, Gohar H M, Morin D E et al 1996 Use of hypertonic saline-dextran solution to resuscitate hypovolemic calves with diarrhea. American Journal of Veterinary Research 57 97-104 Constable P D, Hinchcliff K W, Muir W W 1998 Comparison of anion gap and strong ion gap as predictors of unmeasured strong ion concentration in plasma and serum from horses. American Journai of Veterinary Research 59 881-887... 

McKirnan M D, Williams R L, Limjoco U et al 1994 Hypertonic saline/dextran versus lactated Ringer s treatment for hemorrhage in dehydrated swine. Circulatory Shock 44 238-246... 

Moon P F, Snyder J R, Haskins S C et al 1991 Effects of a highly concentrated hypertonic saline-dextran volume expander on cardiopulmonary function In anesthetized normovolemic horses. American Journal of Veterinary Research 52 1611-1618... 

Therapeutic fluids include crystalloid and colloid solutions. The most commonly used crystalloids include normal saline, hypertonic saline, and lactated Ringer s solution. Examples of colloids include albumin, the dextrans, hetastarch, and fresh frozen plasma. 

Tlie combination of dextran 70 (a colloid) with hypertonic saline resulted in acceptable resuscitation in experimental dehydration in calf and swine models (Constable et al 1996, McKiman et al... 

In humans, dextran administration is associated with a decrease in factor VIII activity, decreased fibrin clot formation and dilutional coagulopathy (Roberts Bratton 1998). Dextran 70 inhibits equine platelet aggregation in vitro (Heath et al 1998) but other effects on hemostasis have not been investigated. Dextran 70 has been used for its presumed antithrombotic properties in horses with a clinical diagnosis of verminous aneurysm (Table 17.9) (Greatorex 1977). Dextran 70, when combined with hypertonic saline, resulted in a... 

Unfortunately, beneficial outcome data attributable to administration of these hypertonic solutions also have been lacking. Most of these studies were conducted in prehospital and emergency department settings using 250 mL 7.5% sodium chloride with or without 6% dextran-70. A meta-analysis of randomized, controlled trials found no statistical difference between the survival rates of patients receiving the hypertonic saline solutions and those receiving standard isotonic crystalloid solutions.Part of the explanation for this finding may... 

For example, 7.5% NaCI in 6% dextran-70 (hypertonic saline-dextrose) has been studied in a variety of animal models and in human trauma patients with some success. Particularly promising are animal studies of closed head injury, which suggest not only a hemodynamic benefit but also a sustained decrease in intracranial pressure. Studies in this system as well as in burn and trauma patients are ongoing. 

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