Veterinary Clinics of North America: Large Animal Practice
Fluid Therapy in Horses with Acute Diarrhea
Section snippets
Fluid Balance and Compartmental Distribution
The total body water of a 450 to 500 kg horse is approximately 300 liters. The total body water is divided into two major compartments, the intracellular fluid volume which consists of approximately 200 liters, and the extracellular fluid volume which equals approximately 100 liters. Although these two compartments differ markedly in electrolyte composition, they are in osmotic equilibrium and water is freely diffusible between them. The distribution of body water between these two compartments
Evaluation of Accumulated Deficits
It is convenient to visualize fluid and electrolyte alterations during dehydration as primary water deficits or primary electrolyte deficits. In acute diarrhea, large amounts of both water and electrolytes are lost. The clinicopathologic consequences of these losses depend upon the composition of the fluid lost by all routes as well as the patient’s intake and absorption during the clinical course. The following discussion will describe an approach to evaluating the existing deficits of fluid
Fluid Therapy
Formulation of a plan for fluid therapy for a dehydrated horse consists of four basic elements: the replacement of existing deficits; the satisfaction of daily requirements; the replacement of anticipated additional losses; and the monitoring of the patient’s response to therapy.
The therapeutic plan is designed for a specific period of time, generally 12 to 24 hours. At this time, the plan is reevaluated and may be modified according to the monitored response to therapy. This allows some
Route and Rate of Administration of Fluids
Replacement of initial deficits of fluids should be accomplished through an intravenous route. The rate of administration of fluids should be varied according to the clinical circumstances. Flow rates of 10 liters per hour or more may be necessary in patients with marked contraction of fluid volume and impending hypovolemic shock. These patients may also benefit from the early infusion of 2 to 3 liters of plasma or plasma expanders. Many clinicians recommend rapid intravenous infusions of 5 per
Clinical Examples: Fluid Therapy for Acute Diarrhea
The three horses presented in Table 2 all have acute diarrhea but with varying alterations of fluid and electrolytes. The accumulated deficits were estimated on the basis of the discussion in previous sections. Briefly stated the basic assumptions and formulas are:
The water deficit is equal to 0.9 liters per kg × weight loss (kg), the initial weight being 450 kg.
The sodium deficit is estimated on the basis of increased packed cell volume and plasma protein which serve as indexes of decreased
References (10)
- et al.
Anatomy of body water and electrolytes
Am. I. Med.
(1959) Functions of the equine large intestine and their interrelationships in disease
Cornell Vet.
(1975)- et al.
Interrelationships between serum sodium concentration, serum osmolality and total exchangeable sodium, total exchangeable potassium and total body water
J. Clin. Invest.
(1958) A practical approach to fluid therapy in the horse
Aust. Vet. J.
(1972)- et al.
Plasma clearance of [51Cr] albumin into the intestinal tract of normal and chronically diarrheal horses
Am. J. Vet. Res.
(1977)
Cited by (24)
Water
2013, Equine Applied and Clinical Nutrition: Health, Welfare and PerformanceWater Homeostasis and Diabetes Insipidus in Horses
2011, Veterinary Clinics of North America - Equine PracticeCitation Excerpt :Although providing supplemental salt (NaCl) in the diet has been advocated to increase water intake, no increase in water consumption or urine volume was observed in ponies fed 5 to 10 times the daily salt requirement (equivalent to about 350 g of sodium chloride for a 500-kg horse).28 Horses with medical problems causing greater daily water loss, including chronic diarrhea, renal insufficiency, diabetes mellitus (DM), or DI, also have comparably greater water intake to maintain water balance.1 The manner in which both water and feed are provided to horses can affect drinking behavior and water balance.
Fluid, Electrolyte, and Acid-Base Balance
2008, Clinical Biochemistry of Domestic Animals, Sixth EditionFluid therapy in horses with gastrointestinal disease
2003, Veterinary Clinics of North America - Equine PracticeHaematological responses of repeated large volume blood collection in the horse
2000, Research in Veterinary Science