Fluid therapy is one of the most widely used and necessary therapies for critically ill patients and those who are not able to hydrate and feed themselves spontaneously. Fluid Therapy in dogs and cats summarizes the fundamentals for understanding the water and electrolyte requirements of critical patients, the types of fluids that can be administered, and the consequences that a decision may entail.

This handbook is published at a particularly relevant time, with the recent developments in orthogonal polarization spectral imaging; the advancements in hemodynamics, which have made it possible to assess the real efficacy of therapy and the side effects fluids can produce if not provided correctly; and the evidence-based advances that have changed the way fluid therapy in both human and veterinary medicine is now provided, which is very different from how it had been performed over the past 30 years.

An attempt has been made in this book to address the topics homogeneously, following a functional approach for readers. Every chapter ends with a clinical case, which is useful for putting into practice what has been explained in the text.

1. Fundamentals of Fluid Therapy, Hemodynamics and Compartmentalization of Fluids in the Body

Fabio Viganò

Introduction

Dynamics and hemodynamics of fluid compartments

Water

Blood volume and cardiac output

Parameters to evaluate the hemodynamic response

Blood volume

Evaluation of cardiac output and stroke volume

Central venous pressure and pulmonary artery occlusion pressure

Clinical hemodynamic monitoring

Water distribution in the body

Osmotic pressure

Colloid oncotic pressure

Glycocalyx

Clinical consequences of the glycocalyx model

Clinical Case: Dehydrated dog with respiratory alkalosis

 

2. Acid-Base Disorders

Fabio Viganò

Introduction

Chemical species involved in the acid-base balance

Traditional approach

Blood gas analyzers

Interpretation of blood gas analysis

Primary disorder

Compensatory responses

Base excess (BE)

Anion gap (AG)

Total oxygen content (CaO2)

Oxygen parameters to evaluate the effectiveness of oxygenation

Rule of 5

Rule of 120

Strong ion theory (Stewart’s approach)

Chemical species involved

Dependent and independent variables

Examples of pH variations according to the nontraditional approach

Fluid therapy and SID

Clinical case, example

Strong ion gap (SIG)

Correction of acid-base disorders

Metabolic acidosis

Metabolic alkalosis

Respiratory acidosis

Respiratory alkalosis

Mixed disorders

Clinical Case: The cat who couldn’t urinate

 

3. Fluids: when and how to administer them

Fabio Viganò

Introduction

Daily intravenous fluid therapy

Daily water requirements

Hypotonic solutions

Antidiuretic hormone and fluid therapy

Fluid therapy under general anaesthesia

Daily fluid therapy

Hydration

Calculation of daily fluid therapy

Hemodynamic monitoring

Heart rate and cardiac output

Pulse quality

Capillary refill time (CRT)

Mucous membrane colour

Body temperature

Jugular vein distension

Urine production

Parameters to evaluate the hemodynamic status

Invasive blood pressure (IBP) measurement

Measurement of lactatemia

Fluid resuscitation

Goal-directed therapy

ROSE model (Resuscitation, Optimization, Stabilization, Evacuation)

Crystalloids

Isotonic solutions

Hypertonic solutions

Colloids

Synthetic colloids

Natural colloids

Clinical Case: Consequences of gastroenteritis

 

4. Electrolyte Disorders

Fabio Viganò, Corinna Uboldi

Introduction

Osmosis

Osmolarity and osmolality

Sodium

Hyponatremia

Hypernatremia

Potassium

Hypokalemia

Hyperkalemia

Calcium

Hypocalcemia

Hypercalcemia

Phosphorus

Hyperphosphatemia

Hypophosphatemia

Chloride

Hyperchloremia

Hypochloremia

Magnesium

Hypomagnesemia

Hypermagnesemia

Clinical Case: Electrolyte and acid–base imbalances during vomiting

 

5. Hemorrhagic Shock

Brett Montague, Deborah C. Silverstein

Introduction

Pathophysiology of hemorrhagic shock

Compensatory shock

Early decompensatory shock

Late decompensatory shock

Metabolic sequelae of hemorrhagic shock

Aetiology of hemorrhagic shock

Diagnosis

Laboratory data

Monitoring

Shock index

Ultrasonography

Clinical management

Triage

Hypotensive resuscitation

Fluid therapy in hemorrhagic shock

Postresuscitation care

Reperfusion injury

Trauma-induced coagulopathy

Clinical Case: Hemorrhagic shock following a ruptured hepatocellular carcinoma

 

6. Microcirculation and Fluid Therapy

Deborah C. Silverstein

Introduction

Structure and function of the microcirculation

Microvascular perfusion – systemic control

Microvascular perfusion – local control

Microvascular changes with trauma and hemorrhagic shock

Microvascular changes with sepsis

Monitoring of the microcirculation vs. macrocirculation

Effects of fluid resuscitation on the microcirculation in trauma and hemorrhagic shock

Effects of fluid resuscitation on the microcirculation in sepsis

Conclusion

Clinical Case: Microcirculatory changes in a dog with sepsis secondary to bite wounds

 

Subject Index

Fabio Viganò

DVM, Cert. Emergency Medicine and Surgery, Specialist in Small Animal Diseases, ECVECC AM

Clinica Veterinaria San Giorgio, San Giorgio su Legnano (Italy)

 

Deborah C. Silverstein

DVM, DACVECC

Department of Clinical Sciences and Advanced Medicine

University of Pennsylvania School of Veterinary Medicine Philadelphia, Pennsylvania (USA)