Equine Patient Assessment + Key Parameters Flashcards
1
Q
Adult temp
A
37.5 - 38.5 C
2
Q
Foal temp
A
37.2 - 38.9
3
Q
Total body water
A
62 - 67% BW
4
Q
Hypovolaemia
A
- Dec in CIRCULATING BLOOD VOL
- Loss of circulating IV fluid (plasma vol)
5
Q
Dehydration
A
- Loss of INTERSTITIAL/IC (intracellular) fluid
- No change in circulating vol
6
Q
Hypovolaemia -> dehydration
A
- E.g. H+ - blood loss from circulating blood/IV component -> draws additional fluid from interstitial fluid
- Severe cases -> H+ cannot be stopped, will draw from intracellular fluid
7
Q
Dehydration -> hypovolaemia
A
- E.g. Sweat - fluid loss from interstitial component of ECF
- If animal mildly dehydrated, can compensate + won’t draw upon other components if have access to water
- Profuse sweating - will draw fluid from intracellular component to compensate
- Severe cases - draw fluid from circulating blood vol
8
Q
HR
A
32 - 46 bpm
9
Q
Normal CVS parameters CE
A
- HR = 32 - 46
- Pulse quality (palp facial a.) = strong
- Jugular refill = rapid
- MM = pink
- CRT = < 2 s
10
Q
Mod endotoxaemic CVS CE
A
- HR = > 60
- Pulse quality = moderate
- Jugular refill = slow
- MM colour = dark pink -> red
- CRT = 2 - 3 s
11
Q
Severe endotoxaemia CVS CE
A
- HR = > 100
- Pulse quality = weak
- Jugular refill = sluggish
- MM colour = red -> purple
- CRT = > 3 s
- Sustained colour change = problem w/ peripheral perfusion
12
Q
Normal moisture MM
A
- Most
13
Q
Dehydration of MM
A
- Tacky/dry
14
Q
Patient evaluation - dehydration
A
- Tacky/dry mucous membranes
- Prolonged skin tent - older horses may have due to dec elasticity
- Sunken eyes (foals) - if in adults, then severe
- (Tear film)
15
Q
Patient evaluation - hypovolaemia
A
- Tachycardia
- Tachypnoea
- Weak Peripheral pulse
- Reduced Jugular refill
- Altered Mentation - quiet, dull
- Prolonged CRT - not refilled quickly
- Cold Extremities
- Decreased Urine output - lack of perfusion to kidneys
16
Q
Packed cell vol (PCV)
A
- Ref = 32 - 50%
- Inc w/ splenic contraction, exercise, colitis (stress induced)
- Dec w/ anaemia/whole blood loss
17
Q
Total solids/total serum protein (TSP)
A
- Refractometer for TS
- Normal, TP = 55 - 69 g/L
- Inc w/ inflam - heavy parasite burden, hypovolaemia
- Dec w/ hypoproteinaemia, colitis - GIT protein loss, PLE/PLN
18
Q
Blood lactate conc
A
- Normal < 1 mmol/L
- Lactate produced during anaerobic metabolism, sensitive indicator of altered tissue perfusion
- Excessive inc w/ hypovolaemia - inc lactate production in tissues, reduced lactate clearance in liver + kidneys
- Inc w/ sepsis or endotoxaemia
- Persistent hyperlactaemia = poor PX
19
Q
Renal indices for poor tissue perfusion
A
- Serum creatinine conc (80 - 177 µmol/L
- Pre-renal azotaemia - associated w/ dehydration/hypovolaemia
- Pre-renal azotaemia should respond to Tx but if not then IVFT to correct hypovolaemia/dehydration then renal dysfunc Tx
Urine output/USG - Inc USG = early indicator of dehydration
- Dec urine production/anuria = early indicator of hypovolaemia
20
Q
Arterial BP
A
- Direct/indirect estimate of perfusion
21
Q
Arterial blood gas
A
- Assessment of arterial oxygenation
- Identify any acid-base imbalances
- In states of hypovolaemia, metabolic acidosis will
inevitably be present - should be corrected w/ IVFT
22
Q
Central venous pressure (CVP)
A
- Indirect estimate of blood vol
23
Q
Fluid therapy
A
- Treat hypovolaemia and dehydration
- Prevent hypovolaemia + dehydration in horses that are unable to drink or to
absorb fluids from the GIT - Treat specific electrolyte or acid-base abnormalities
24
Q
Hypovolaemia lab parameters
A
- HR > 60 bpm
- CRT > 2 s
- PCV/TP > 70%/g/L
- Lactate > 2.5 mmol/L
- Creatinine > 177 µmol/L
25
Hypovolaemia - fluid admin route
- IVFT only option
26
Dehydration - fluid admin route
- 1). Oral (free choice)
- 2). Enteral (intragastric) - nasogastric tubing, intermittent, place tube at reg intervals/in-dwelling nasogastric tube attached to head collar + sutured for CRI
- 3). IV - most severely dehydrated/hypovolaemic
27
Enteral FT
- Correcting dehydration without need for voluntary intake
- Still requires normal GIT function
- Nasogastric intubation
Intermittent - 6 - 8 L every 40-60 mins bolus, can cause abdominal pain Indwelling
- CRI - Max 20 mL/kg/hr (10L/hr)
- Add electrolytes to make isotonic 4.9g/L Salt and 4.9g/L Lo-Salt
- Ideal for hydration of the GIT contents
- Management of impactions of the large intestine
28
IVFT
- Ideal for systemically ill horses & foals
- Only route recommended for; treatment of moderate to severe hypovolaemia; patients with GIT dysfunction (reflux/ileus post-Sx - guarantee fluid received directly into vascular system)
- IV catheter sites - jugular v; cephalic v - foal; lateral thoracic v if jugular not available
29
Crystalloid fluids
- Go-to
- Replacement solutions = isotonic, Hartmann's/Lactated Rigner's (closest to equine plasma), given large vols (40 - 50L, 5 L bags), rapid replacement of IV vol, only 25 - 30% of total vol will remain within circulation 30 min after admin
- Hypertonic solutions - smaller vols to rapidly encourage drawing of fluid into circulating blood vol, rapidly reverse hypovolaemia but rapid follow-up w/ isotonic to prevent dehydration e.g. 7.2% NaCl - max dos 4 mL/kg (2 L) IV bolus, acts within 30 min
- Hypotonic solutions - rarely used
30
Colloid fluids
- Biologic - whole blood, plasma, albumin
- Synthetic - hyroxyethylstarch, gelatins, dextrans
- Rarely used, expensive, AEs, allergic reactions/anaphylactic shock, less readily available
- Indicated in rapid restoration of IV col + crystalloid fluids
- Smaller vols + shorter infusions required for resuscitation
- Don't replace free water so not used alone
31
Replacement fluid rates - IV fluid bolus
= Shock dose - rapid correction of hypovolaemia, normalisation of physical perfusion parameters + inc urination
- 60 - 80 mL/kg
- Give all 1/2 replacement vol rapidly (20 L)
- 40 L bolus takes approx 2 - 3 h via gravity infusion
- +/- hypertonic saline - 4 mL/kg bolus
- Colloid fluids - 10 mL/kg/d - give 3 - 5 mL/kg hetastarch as slow bolus, admin remainder of dose over following in 24 h
32
Replacement fluid rates - 'fluid challenge'
- 10 - 20 mL/kg rapid IV bolus
- Foals (risk of over-hydrating) = 0.5 - 1L as bolus then reassess perfusion
- Repeat until signs of hypoperfusion resolve (3 - 4 times)
33
Maintenance fluid rates
- When already corrected deficit w/ replacement to maintain fluid content
- When not eating/drinking as well - maintains hydration status
- Adult = 2 - 3 mL/kg/h (50 - 70 mL/kg/d
- Neonatal foals - 4 - 6 mL/kg/h (8I 0 - 140 mL/kg/d (neonates have higher body water content)
- + Ongoing losses - D+. gastric reflux, 3rd space loss, sweating
- Discontinuation - look at perfusion parameters then gradual taper to < maintenance for 12 - 24 h before stopping
34
Complications of FT
- Thrombophlebitis
- Electrolyte / acid-base derangements
- Over-hydration (rare) - in foals
