Fluid therapy the basic and applied knowledge

This presentation is on fluid therapy of large animals in case of dehydration

1. FLUID THERAPY THE BASIC AND APPLIED KNOWLEDGE Submitted to: Dr. Arslan Ahmed Submitted by: Dr. Sadia Sanaullah Subject: PG Clinic II

2. What is fluid? Any liquid or gas or generally any material that cannot sustain a tangential, or shearing, force when at rest and that undergoes a continuous change in shape when subjected to such a stress . What is Fluid Therapy? Fluid Therapy is the administration of fluids to a patient as a treatment or preventative measure. It can be administered via an intravenous, intraperitoneal , intraosseous , subcutaneous and oral routes. What is Fluid Therapy?

3. F luid Distribution in Body

4. Types of fluid disturbances Dehydration Electrolyte Imbalance Acid-base Imbalance Disturbance in Oncotic Pressure

5. Intravenous fluids Intravenous fluids are chemically prepared solutions that are administered to the patient. They are tailored to the body’s needs and used to replace lost fluids and/or aid in the delivery of IV medications.

6. Indications of fluid therapy For rapid restoration of fluid and electrolytes in dehydration due to vomiting, diarrhoea , shock due to haemorrhage or sepsis or burns. Total parenteral nutrition. Anaphylaxis, cardiac arrest, hypoxia. Post gastrointestinal surgeries. For maintenance, replacement of loss or as a special fluid.

7. Advantages of fluid therapy Provides the patient with life-sustaining fluids, electrolytes, and drugs. Immediate and predictable therapeutic effects. Preferred for administering fluids, electrolytes, and drugs in emergency situation . Allow fluid intake when patient has GI malabsorption . Permit accurate dosage titration for analgesics and other drugs.

8. Disadvantages Needs hospitalization, costly. Infection Pyrogenic reaction. Discomfort, poor patient compliance. Fluid overload- chance.

9. IV Fluids The majority of an IV solution is sterile water. Solvent and solute Solvent is water Solutes can be molecule called electrolytes or other large compounds such as proteins or molecules.

10. Intra venous Fluids IV fluids come in three different forms Colloids Crystalloids Blood and blood products

11. Colloidal Solutions Colloid solutions are IV fluids containing large proteins and molecules that tends to stay within the vascular space ( blood vessels). They shift the fluids from interstitial to intravascular compartment Colloids are useful in maintaining blood volume. Colloids are expensive, have specific storage requirements, and have a short shelf life. Commonly used colloids includes plasma proteins, salt poor albumin, dextran.

12. Crystalloid Solution Crystalloid solutions are primarily fluids used for IV therapy. Contain electrolytes but lack the large proteins and molecules found in colloids. Crystalloids come indifferent preparations and classified according to their “tonicity”. A crystalloid’s tonicity describes concentration of electrolytes dissolved in water, as compared with that of body plasma.

13. Blood and Blood Products W hen PCV decreases than there is need of blood transfusion. In severe anemia : where there is extreme depletion of oxygen carrying capacity of the blood occurs & life is threatened. PCV between 10 & 15% will benefit from a transfusion. Normal PCV of Ruminants is 24-46% and of equines 32-48%.

14. Isotonic Solutions Tonicity equal to plasma Even distribution between intravascular space and plasma. 5% dextrose Lactated ringer Normal saline

15. Hypotonic Solutions Tonicity lower than body plasma Shift from intravascular space to extravascular space and then to cell. 0.45% NaCl Used for dehydration

16. Hypertonic Solutions Tonicity higher than body plasma Cause the water to shift from extravascular space into bloodstream, increasing intravascular volume. 5% dextrose in 0.45% NaCl

17. Dehydration

18. Types of dehydration Isotonic Dehydration Hypotonic Dehydration Hypertonic Dehydration

19. Commonly Used Fluids Normal Saline Dextrose Saline Balanced Electrolyte S olutions Sodium Bicarbonate Solution Mixture of KCl and Dextrose Saline Dextrose Solution Plasma Expanders Mannitol 20%

20. Normal Saline Composition Indications: Expand Blood Circulating Volume Severe Sweating Pyloric obstruction Abomasal disorder Vomiting

21. How N/S helps in Expansion of Blood Volume Fluid therapy with N/S Increase stroke volume due to increased diastolic and decreased systolic volume Decreased Blood viscosity Decreased vascular resistance/expansion of volume N/S is isotonic with blood composition. Insert a 308mosmol/liter pressure. Na is main electrolyte of extracellular fluids, integral in distribution of fluids and other electrolytes. Chloride ion is 2 nd most important ion, serves as buffering agent in lungs and tissues. Helps to bind CO2and O2 to hemoglobin

22. NaCl is mild acidifying as effective SID=0mEq/L. Has little merit in routine treatment of ruminants, as ruminants develop hypokalemia and hypocalcemia when inappetent . Can act as vehicle for adding other electrolytes and dextrose.

23. Contraindications to the Use of N/S Impaired Kidney Functions Congestive heart failure as can lead to pulmonary edema If infused in too much large quantities can lead to a net acidosis

24. Dextrose Saline Composition Indications Indications Sodium Chloride 0.9% Dextrose 5% Dehydration Vomiting Heat Stroke Mild Diarrhoea

25. Dextrose injected parenterally oxidized to carbon dioxide and water. Sodium chloride provides sodium and chlorine. Used in mild diarrhoea as in this case loss of sodium ions occurs. Na is principal cation of extracellular fluid

26. Balanced Electrolyte Solutions Ringer’s Solution Mildly acidifying isotonic solution. Composition: NaCl 0.9g, KCl 0.03g, CaCl2 0.03g, Distilled water 100mL Indications: Dehydration Alkalosis Electrolyte loses Lactated Ringer’s Solution Alkalinizing hypotonic solution. Composition: NaCl 0.6g, KCl 0.03g, CaCl2 0.02g, sodium Lactate 0.31g (D- and L- lactate), DW 100mL Indications: Mild to moderate acidosis with dehydration

27. Mechanism of Action of Ringer Solution SID ( Effective strong ion difference): it is the strong difference between the cation and strong anion concentration after metabolized anions have been completely metabolized to produce bicarbonate. Solutions having SID greater than 27mEq/L are alkalinizing. Solutions having SID=0 are acidifying. Ringer solution SID= 0mEq/L. so acidifying in nature. A dult ruminants tends to get alkalemic when inappetent so this solution will be preferred. As containing major electrolytes required by body so helps in electrolyte balance. Helps in rehydration as containing sodium helps in expansion of blood volume.

28. Mechanism of action of Lactated Ringer Solution Osmolality 275 mOsmol /L. It is alkalinizing as lactate metabolize into bicarbonate ion. Standard intravenous solution for neonates and horses, as these become acidemic when inappetent .

29. Sodium Bicarbonate Solution Sodium bicarbonate Composition: 1.3% isotonic solution of sodium bicarbonate Indications: Acidosis Sodium bicarbonate Composition: 5% Hypertonic Solution of sodium bicarbonate Indications: Severe Acidosis

30. Sodium bicarbonate solution mechanism of action By alkalinizing serum indirectly cause moment of potassium into cells via an H+/K+ exchange mechanism. Administration of sodium bicarbonate Increase plasma bicarbonate level Buffer excess H + concentration Raise in solution pH

31. Mixture of Isotonic KCl (1.1%) and Dextrose saline Indications: Alkalosis Indications: Parenteral nutrition Liver disorder Hypoproteinemia Extensive burns Amino acid solution

32. Amino acids helps in synthesis of protein. In liver amino acids helps in detoxification. Amino acids are building blocks of proteins. In case of burn inflammatory mediators such as cytokines release results in vasodilation due to which edema develops. So amino acids as building blocks of protein helps to keep fluid in vessel and prevent edema formation.

33. Dextrose Solutions Dextrose 5% Isotonic solution Indications: High fever starvation decreased water intake Dextrose 20%, 25% Hypertonic solution Indications: Parenteral nutrition Ketosis Hypoglycemia

34. Dextrose 5% only purpose is to supply free water Dextrose 25% or 50% provide glucose ( a carbohydrate) which acts as a source of energy.

35. Plasma Expander Dextran 70mL, 500mL How to use? Dextran 6% in normal saline/ 5% dextrose Dose: 10-20mL/kg/day IV Indications: Shock Haemorrhage Burns Endotoxic shock Haemacel 500mL Composition: Polymer form degraded gelatin 3.5% + Electrolytes Na+ K+Ca+Cl Indications: Hypovolemic Shock Haemorrhage Burn Endotoxic Shock

36. Dextran High molecular weight glucose polymers formed by fermentation of sucrose. As mol. Wt. is similar to albumin therefore limited diffusion into interstitial spaces. Results in increase oncotic pressure in blood vessels, due to which fluid stay in vessels. Act as plasma volume expander in contrast to crystalloids, which expand extracellular fluid volume. Haemacel Shorter plasma half life than dextran

37. Mannitol 20% Indications: Cerebral Edema Dose: 0.5g/kg IV

38. Mechanism of action of mannitol It elevates blood plasma osmolality, resulting in enhanced flow of water from tissues, including the brain and cerebrospinal fluids, into interstitial fluids and plasma.

39. Fluid Calculations Replacement = % Dehydration x Bodyweight (kg) x 10 Ongoing losses = Amount per loss (ml/kg) x Bodyweight (kg) x No. of losses Example of overall fluid requirements for 50kg calf: 10 per cent dehydration will result in a deficit of 50 × 0.10 = 5 litres Maintenance fluids for a calf = 50ml/kg/day = 2.5 litres Ongoing losses approximately = 80mls/kg/day = 4 litres Total fluid volume required over 24 hours = 5 + 2.5 + 4 = 11.5 litre

40. Serum calculations by taking FMD as an example 1500g IgG ’s required to produce enough immunity against FMD. If IgG’s checked in serum of a donor cow, found to be 25g then how much blood will be transfused to produce immunity. 25g IgG’s in serum= 1mL serum 1g IgG’s in how much serum= 1/25 1500 IgG’s in how much serum=1/25*1500=60mL Serum is almost 50% of whole blood so 120mL blood will be infused.

41. Blood transfusion calculations Total Volume Infused= ([Patient PCV-Minimum PCV ]/Patient PCV)*Blood Volume Blood Volume is 7-9% of body weight.

42. References Veterinary Medicine by Constable 11 th Edition Volume 1. https://www.succeed-equine.com/succeed-blog/2014/02/05/anemia-horses-part-1-just-equine-anemia/#:~:text=A%20normal%20PCV%20for%20horses,the%20horse%20may%20be%20anemic . https://www.ncbi.nlm.nih.gov/books/NBK545210 /