fluids

Question 1

Fluid Composition for Orally Administered Fluid Therapy

Answer 1

FOR EVERY 21 L OF WATER

• NaCl 10 g
• NaHCO3 15g
• KCl 75 g
• K2HPO4 60g

Question 2

Advantages of hetastarch include maintenance of plasma oncotic effect for up to…

Disadvantages

Answer 2

up to 24 hours following administration and the ability to give as a rapid bolus

negative effect on coagulation has been demonstrated in healthy equids

in critically ill humans: increased risk of mortality and acute kidney injury in patients receiving hetastarch

Question 3

MAP can also be calculated by

Answer 3

MAP = 1 ⁄3 × (SAP − DAP) + DAP

Question 4

ideal cuff … ratio for BP measurement

Answer 4

width-to-circumference of 0.25 to 0.35

for use on the tail or limbs of horses

Question 5

Normal pleural fluid values

Answer 5

protein concentration <25 g/L and

total nucleated cell count <5000/μL.

Question 6

Pleural air is then evacuated via

Answer 6

placement of a cannula or 14-gauge catheter in the caudodorsal lung field.

The 12th or 13th intercostal space is a suitable location

Question 7

Excess EDTA in a low-volume sample of peritoneal fuid will

Answer 7

falsely increase the total protein on refractometry (often by 9–10 g/L higher)

Question 8

influence of abdominal surgery on abdo tap TP/TNCC

Answer 8

Typically, if no enterotomy was performed,

TNCC: increases for 4 to 7 days and normal by 14 days.

TP remain elevated for 3 to 4 weeks after surgery.

Question 9

how much urine do helthy horses produce?

Answer 9

1 to 2 mL/kg per hour of urine.

Question 10

What is Obstructive shock

Answer 10

from lack of blood flow through the heart or great vessels as a result of

• thrombosis (atrial or pulmonary),
• constrictive pericarditis,
• cardiac tamponade, or
• pleural space disease (e.g., pneumothorax).32

This condition is characterized by decreased preload OR increased afterload and results in circulatory failure.3

Question 11

Maldistributive shock

Answer 11

vasodilatory shock

endothelial dysfunction in response to neutrophil generated cytokines, proteases, lipid mediators, and oxygenderived free radicals

septic, anaphylactic, or neurogenic causes

Question 12

α1-Adrenergic receptor/ Alpha2-adrenergic stimulation have which effect on vascuature?

Answer 12

alpha1 - vasoconstriction

alpha2 - vasodilation

Question 13

Which effects do Beta 1 and 2 adrenergic stimulation have on the cardiovascular system?

Answer 13

β1-Adrenergic receptor stimulation

• primarily cardiac effects with
  
  • increases in heart rate (chronotropic effect) and
  • contractility (inotropic effect).

β2-Receptor stimulation

• vasodilation of the
  
  • arteries of coronary vessels,
  • visceral organs, and
  • skeletal muscle

Question 14

Effect of Dopaminergic stimulation on cardiovasc system

Answer 14

active at adrenergic (α and β) and dopaminergic receptors in a dose-dependent manner

• improves myocardial contractility,
• increases heart rate, and
• results in peripheral vasoconstriction.

low doses: rather Beta (pos inotropy)

high doses: rather Alpha (vasopressor ++)

Question 15

True or false?

Phenylephrine administration results in increased cardiac output.

Answer 15

False

α-agonist resulting in increased Systemic Vascular Resistance, MAP, and

decreased CO.

Question 16

Vasopressin works on which receptors?

Answer 16

promotion of water conservation in the collecting tubule of nephrons (V2 receptor)

vasoconstriction via V1 receptors

Question 17

Which signs indicate the limits to fluid resuscitation

Answer 17

60–80 mL/kg total volume,

CVP >15 mm Hg,

declining Pao2,

peripheral edema

Question 18

Difference between Type A and B lactic acidosis

Answer 18

A: inadequate delivery of oxygen to peripheral tissues resulting from hypovolemia, hypoxemia, anemia, or decreased perfusion pressure

B: abnormal tissue utilization of oxygen, including mitochondrial dysfunction, or abnormal clearance of lactate

Question 19

How is lactate eliminated from the circulation?

Answer 19

2% unchanged in urine

metabolisation in liver and kidney to glucose or

pyruvate –>> AcCoA

Question 20

treatment of hypoventilation secondary to head trauma, encephalitis, or hypoxic-ischemic encephalopathy

Answer 20

• Caffeine: most frequently used in practice because of ease of administration, cost, and wide therapeutic index.
• Doxapram has a short duration of action requiring frequent or CRI administration, which limits use despite evidence of improved ventilation. increase in myocardial oxygen consumption!!!
• Theophylline is similar to caffeine; however, it has a narrow therapeutic index with adverse effects

Question 21

Is rectal fluid administration useful? When and how?

Answer 21

rectal administration at a rate of 5 mL/kg/h TAP WATER

equivalent to more than twice the accepted maintenance fluid rate, was well tolerated by the horses and was technically easy to perform.

a significant decrease in albumin concentration was seen only with i.v. treatment,

not with NGT or rectal fluid treatment.

Question 22

Why is albumin a high contributor to oncotic pressure in the blood vessels?

Answer 22

Albumin,

• due to its small size (69 kDa),
• negative charge and
• high concentration,

exerts 60–80% of the oncotic pressure (Magdesian 2003).

Question 23

Size of particles in HES

Answer 23

Older products, such as hetastarch, have higher molecular weights, ranging from 450 kDa to 600 kDa,

whereas newer formulations have much lower molecular weights (e.g. tetrastarch, 130 kDa) only disadvantage: Tetrastarch is cleared quicker

Question 24

True or False?

The effect of a colloid on oncotic pressure is determined by the number of oncotically active particles in a solution, not the size of the particles.

Answer 24

True

Question 25

How is HES cleared from the blood?

Answer 25

1. Hydroxyethyl starch molecules are excreted primarily (approximately 70%) by the kidneys with a smaller portion being taken up from the plasma by the reticuloendothelial system. 2. Small molecules (45–60 kDa) are excreted rapidly into the urine, whereas larger molecules must first be broken down by amylase into a size that can be filtered through the glomeruli (\<60 kDa in humans)

Question 26

effects of HES solutions on the equine kidney

Answer 26

controversy in equids .No changes were identified in urine GGT:creatinine ratios after infusion of TES in healthy neonatal foals for 24 h after infusion and in healthy adult horses for 4 h after infusion of PES, respectively * **increased glomerular oncotic pressure** \> _decreased urine output_ (Honore et al. 2008). * **accumulation of starch molecules** within the nephrons, leading to _swelling of the proximal tubular epithelial cells, termed **osmotic nephrosis**_

Question 27

effects of HES on coagulation

Answer 27

* **Decreases in fibrinogen** have been repeatedly documented after HES administration in horses * incorporation into clots\>\> weaker clots * **binding of vWF and Factor VIII** by HES molecules

Question 28

which values of routine haematology and biochemistry measurands in the horse might vary more individually, which less?

Answer 28

High individuality * Haematology (red blood cell count, mean corpuscular haemoglobin and mean cell volume) and * biochemistry measurands (total protein, globulins, albumin, gamma-glutamyl transferase, aspartate aminotransferase) low individuality * Two haematology (mean corpuscular haemoglobin concentration and platelets) and * three biochemistry measurands (chloride, glucose and sodium)

Question 29

are there meds that can reduce lactate in the blood?

Answer 29

beta-adrenergic antagonists effectively reduce [LAC]. Increased lactate concentrations [LAC]

Question 30

effects of xylacine on cerebral perfusion and intracran pressure

Answer 30

**6 horses, 15 minutes,** **1 mg/kg** Administration of xylazine to anesthetized horses resulted in an * increased Cerebral Persuion Press due to * **decreased intracranial pressure** with * with concurrent increased MAP. * **\>\>\>\>suggesting vasoconstriction** Administration of xylazine to standing horses did not result in a change in ICP but it is likely to increase it with time

Question 31

How do Plasma-Lyte 148 and Normosol-R differ from LRS Indications?

Answer 31

more physiologic sodium:chloride ratio and contain magnesium rather than calcium INDICATED: may be administered concurrently with blood products and bicarbonate CONTRAINDICATED: in cases where neuromuscular blockade is a concern (e.g., botulism).

Question 32

Outcome and complications in horses administered sterile or non-sterile fluids intravenously

Answer 32

no difference in s_urvival to discharg_e Horses that received no sterile fluids were * _more likely to develop a jugular vein complication_ * more likely to have electrolyte abnormalities consistent with hyperchloremic metabolic acidosis

Question 33

prolonged treatment with balanced electrolyte solutions can result in which electrolyte derangements? how can these be avoided?

Answer 33

Hypernatremia hypo kalemia, magnesemia, calcemia start with adding 0,05meq Potassium/HOUR (max 0.5) add 1g MgSo4 per L add 10ml Calcium 23% per L

Question 34

Bicarb - how much and how to administer

Answer 34

Bicarbonate defcit= (Bicarbonate desired −Bicarbonate measured) × body weight (kilograms) × 0,3 (extracellular fuid compartment coeff) First, administer 50% of the bicarbonate deficit (see later) rapidly over 1 to 2 hours followed by the remaining 50% over 12 to 24 hours. DONT MIX WITH CALCIUM

Question 35

1 g NaHCO3 = ………….mEq

Answer 35

1 g NaHCO3 = 12 mEq NaHCO3

Question 36

dose and side effects of hypertonic saline administration

Answer 36

2 to 4 mL/kg, administered as rapidly as possible Iatrogenic metabolic acidosis, hypernatremia, and hypokalemia

Question 37

For horses with a pH ≤7.2 caused by metabolic derangements (nonrespiratory) following shock - which fluids are indicated?

Answer 37

**crystalloid dosing (80 mL/kg in 1 h)**, **isotonic bicarbonate (1.3%)** therapy is indicated. First, administer 50% of the bicarbonate deficit (see later) rapidly over 1 to 2 hours followed by the remaining 50% over 12 to 24 hours.

Question 38

vascular space (VS) and extracellular ECF space contain which amount of volume

Answer 38

ECF is roughly 30% of body weight, VS is roughly 8% of body weight

Question 39

administration of hypertonic fluid has which side effects

Answer 39

**Iatrogenic metabolic acidosis**, **hypernatremia, and hypokalemia** may occur after hypertonic saline administration

Question 40

metaanalyses in humans failed to support the theory of improved resuscitation through the use of colloids over crystalloids; however, colloids may be indicated in patients with

Answer 40

hypoproteinemia, severe blood loss, or those in need of clotting factors or immunoglobulins. (naturak) !!! side effects of synthetics!!!!!

Question 41

half life of hetastarch

Answer 41

24h

Question 42

True or False? Synthetic colloids do not register on a refractometer.

Answer 42

TRUE evaluation of oncotic pressure requires the use of a colloid osmometer

Question 43

Side effects of Hetastarch. Is there an alternative?

Answer 43

**increased risk of mortality** (human med) **coagulopathies** (Equine) **acute kidney injury** (human) use of hetastarch in horses with underlying renal insufficiency is cautioned, and its **use is restricted to those with clinical signs of acute hypoproteinemia.** Recently tetrastarch (6%) was evaluated and shown to have a _more sustained effect on COP with fewer adverse coagulopathic effects_ than hetastarch. Both hetastarch and tetrastarch can be dosed at 10 mL/kg.

Question 44

Blood transfusions: If cross-matching is unavailable, use a……as donor.

Answer 44

non-Thoroughbred gelding

Question 45

Abdominocentesis: Excess EDTA in a low-volume sample will falsely

Answer 45

increase the total protein on refractometry (often by 0.9–1.0 g/dL higher)

Question 46

With intestinal strangulation how does abdominal fluid change in the first 6 hours?

Answer 46

**first 1–2 hours**: TP increases such that the fluid is clear but more yellow. **After 3 to 4 hours:** red blood cells also leak, and the fluid is more orange or pink. **After 6 hours or more**, white blood cells increase gradually, with the progression of intestinal necrosis.

Question 47

Which percentage of neutros is in abdo fluid?

Answer 47

neutrophils make up approximately **40% to 50%** of cells, with the remainder being lymphocytes, macrophages and peritoneal cells.

Question 48

When does abdo fluid normalize post colic sx without enterotomy?

Answer 48

white blood cell count increases for 4 to 7 days and returns to normal by 14 days total protein elevated for 1 month

Question 49

Normal horses produce how much urine per hour?

Answer 49

1 to 2 mL/kg per hour of urine.

Question 50

Obstructive shock results from

Answer 50

lack of blood flow through the heart or great vessels as a result of thrombosis (atrial or pulmonary), constrictive pericarditis, cardiac tamponade, or pleural space disease (e.g., pneumothorax).

Question 51

Obstructive shock is characterized by which changes in pre- and afterload?

Answer 51

**decreased preload** **or** **increased afterload** and results in circulatory failure

Question 52

Administration of IV emergency boluses is stopped when normalization or plateau of perfusion parameters is observed or when limits to fluid resuscitation are reached. Name three reasons to stop bolusing

Answer 52

60–80 mL/kg total volume, CVP \>15 mm Hg, declining Pao2, peripheral edema

Question 53

Reihenfolge des einsatzes von vasoactive medication in equine patients

Answer 53

1. dobutamine (2–5 μg/kg/min) 2. Norepinephrine 3. Vasopressin

Question 54

types of lactic acidosis

Answer 54

_TYPE A :_ **inadequate delivery of oxygen to peripheral tissues** resulting from hypovolemia, hypoxemia, anemia, or decreased perfusion pressure _TYPE B:_ **abnormal tissue utilization of oxygen**, including mitochondrial dysfunction, or **abnormal clearance of lactate**

Question 55

Hypercapnia (elevated Paco2) is commonly observed in cases of

Answer 55

hypoventilation and V/Q mismatch

Answer 56

V/Q mismatch

Question 57

Oxygen supplementation is indicated when the Pao2 falls below

Answer 57

Pao2 falls below 60 mm Hg or Sao2 \< 90%

Question 58

Indications for mechanical ventilation include…. Name diseases where this might become necessary

Answer 58

**marked hypoxemia or hypoventilation** (pHa \<7.3 with **Paco2 \>65 mmHg** or **Pao2 \<60 mmHg**) despite maximal medical therapy, and **fatigue or excessive work of breathing:** botulism, hypoxemic-ischemic encephalopathy, or ARDS

Question 59

Delayed blood gas analysis may result in

Answer 59

increased PaCo2, decreased pH, decreased glucose, and increased lactate as blood cells continue to metabolize nutrients

Question 60

PAo2 and its relation to fraction of inspired oxygen (Fio2) in the horse

Answer 60

Pao2 = 5x Fio2 in the healthy standing horse; therefore, in a patient breathing room air at sea level (**Fio2 = 21%**), expected Pao2 concentration is approximately **100 mm Hg** with an Sao2 \>93%

Question 61

The causes of hypoxemia can be further differentiated through the administration of supplemental oxygen and evaluation of oxygen saturation. failure to increase Pao2 to 100 mm Hg suggests… Improvement of Pao2 above 100 mm Hg suggests

Answer 61

failure to increase Pao2 to 100 mm Hg: right-to-left shunting or massive pulmonary thromboembolism Improvement suggests: V/Q mismatch or a diffusion disturbance

Question 62

Nutritional Maintenance requirements for healthy adult horses at rest are estimated to be

Answer 62

30 to 40 kcal/kg per day