Presentation on clinical signs of hypovolemic shock and the best ways to approach stabilizing these patients before sending them on to a referral center with more sophisticated equipment for treating such cases.

1. HYPOVOLEMIC SHOCK
By: Abigail Schmidt

2. What is shock?
 Shock is a syndrome that is the clinical result
of oxygen delivery insufficiency to the cell
requirements of the body
 Hypovolemic
 Absolute: loss of blood volume or fluid
 Relative: cardiogenic problem or venous
obstruction
 OR
 Hyperdynamic
 Most common in septic animals

3. HYPOVOLEMIC SHOCK
 Most common type
 Inadequate circulating volume to deliver
oxygen effectively to tissues
 Loss of intravascular volume
 Dehydration i.e. vomiting
 Blood loss i.e. splenic rupture
 3rd spacing of fluids i.e. into distended stomach

4. Signs of Hypovolemic Shock
 Compensatory events take place:
 Tachycardia (low preload = reduces cardiac output)
 Peripheral vasoconstriction
 Hypotension
Decreased perfusion to essential organs,
development of acidosis

5. Primary Clinical Signs
 Pale MMs
 Prolonged CRT
 Tachycardia
 Tachypnea
 Cool extremities
 Poor peripheral pulses
(bounding in early stage)

6. Triage Primary Assessment
ABCD:
 AB: Airway & Breathing
 Is P breathing? Is airway patent?
 Is P working too hard to breathe?
 C: Circulation
 Is heart beating effectively?
 ASSESS FOR SHOCK
 MM/CRT, BP, Pulse Assessment
 D: Debilitating Disease
 Neuro assessment
 Minimum BW: renal parameters, PCV/TP, ALT,
Glucose, E-lytes

7. Triage 2
 Secondary Survey
 Respiratory
 RR, RE, MM, URT (inspiratory) vs LRT (expiratory)
 LOCALIZE
 Cardiovascular
 Arrhythmias, tissue perfusion (BP, lactate, CRT, MM)
 SHOCK
 Neurological
 Abdominal

8. VITAL 1st STEPS
 Necessary to increase tissue perfusion via
fluids
 NEED to exclude:
 Heart disease
 Respiratory disease
 Intracranial disease
BEFORE loading patient with shock-dose rate fluids

9. Heart Disease
 Failure of pump, caused by:
 Heart disease
 Cardiac tamponade
 Arrhythmias
 Thoracic auscultation
 Murmurs
 Pulmonary edema heard as crackles
 Ascites/Jugular distension
Large volume fluid
administration
contraindicated!!!

10. Respiratory Disease
 Tachypnea/Dyspnea with increased sounds
heard on auscultation
 Crackles, wheezes, etc.
 ALTERNATIVELY: dullness indicates pleural
effusion, another contraindication to shock fluids
 Altered mentation/increased ICP
 Neurologic signs
 Seizures, Blindness, Absent PLR, Incoordination etc.
Intracranial Disease

11.  Low BP  activation of sympathetic nervous
system
 Tachycardia
 PeripheralVasoconstriction
 Fluid retention
 Protective response may make patients seem
more stable than what they truly are.
Pathological Consequences
In attempt to
maintain BP and
perfusion

12. What to do BEFORE referring
 Check important parameters:
 HR, BP, temperature
 BP may initially be normal due to sympathetic NS
 Then decline/drop low
 MM, CRT, Pulse rate/quality, RR
 Cats vs. Dogs
 Dogs: bradycardia
 worsening “shock” state = worse prognosis
 Cats often don’t present tachycardic (less scary)
 Cats more susceptible to fluid overload
 Monitor respiratory rate/effort!
 Cats more prone to hypothermia  active warming

13. Circulatory & Hypovolemic Shock
Clinical Sign Vasodilatory Vasoconstrictory
Mild/ Moderate Severe/ Compensated Decompensated
Heart rate 130-150 150-170
170-200, may become
bradycardic
Pulse strength
Bounding (due to dilated
blood vessels)
Weak becoming absent.. …
Mm colour Bright red (hyperemic) Pink to Pale becoming.. White/grey
CRT
<1sec (blood pooling in
vessels)
~2 seconds >2 seconds
Temperature of
Extremities
Warm (vasodilation)
Cooler
(vasoconstriction)
Cool
Metatarsal pulse
palpable
Easily Just Absent

14. WHY give Fluids for
Hypovolemic Shock
- Lack of perfusion can kill animals quickly
OR
- Shock consequences can cause significant
mortality in the days following insult/injury
Cellular
Hypoxia
Free radical
generation
Inflammatory
Mediators

15. SIRS  MODS  DIC
 Systemic Inflammatory Response Syndrome
 Inflammatory mediators cause disruption of
homeostasis
 Loss of vascular tone
 Endothelial permeability barrier disruption
 Stimulation of coagulation
 Microvascular thrombosis resulting in…
 Multiple Organ Dysfunction Syndrome
 Disseminated Intravascular Coagulation
 IV activation of coagulation with loss of localization
DIC aka

16. Shock Treatment Aims
 Provide oxygen support
 Connect to appropriate monitoring
 Vascular access and BP
 Shock fluid boluses to restore vascular perfusion
and oxygen delivery to tissues
 Pain medications if needed
 Stabilize the patient and send to IndyVet! 

17. Isotonic Crystalloids
i.e. Hartmann’s aka LRS,
0.9% Sodium Chloride
 Same concentration of solutes as blood; same
osmotic pressure
 Small molecules freely pass out of BVs, able
to enter all body compartments
 1/5 of total volume given = actually remain in BVs
1-2 hrs later

18. Crystalloids 2
 “Shock doses” = 60-90 ml/kg, but given in
incremental boluses delivered over 15-20 min
 Assess P after each bolus; repeat if necessary
**Rapid expansion of blood volume with
crystalloids may worsen blood loss
**Risk of interstitial edema, dilution of RBCs
and clotting factors with repeated boluses

19. Colloids
i.e. Hetastarch, Dextran 70
 Large molecules which do NOT pass out of BVs
 Expand IV space by increasing oncotic pressure
 “Shock doses” = 20 ml/kg
 Given as boluses of 5-10 ml/kg
 Cons
 Synthetic can cause
acquired coagulopathy
 Expensive, not multi-
purpose
 Pros
 Less volume needed
 Useful with large Ps
 IV expansion lasts longer
(up to 12 hrs)

20. Hypertonic Saline
i.e. 7% NaCl
 Rapid expansion of IV compartment
 Draws H2O into vascular space from interstitial
compartment, endothelial cells, and RBCs
 “Shock dose” = 4-7ml/kg of 7% hypertonic saline
 Given over 20 min
 Cons
 Short-acting, benefits last
<1 hr
 Administration may result
in bradycardia &
arrhythmias
 CANNOT BE USED if P is
dehydrated or has marked
electrolyte disturbances
 Pros
 Small volumes needed
 CV function improvements
 Myocardial contraction,
 Head trauma, penetrating
wounds, reduces
inflammation

21. Blood Products
 NOT the 1st line of treatment for
shock
 Can’t be given fast enough
 Risk transfusion reactions
 Animals in shock don’t die of
anemia
 They die of LACK of vascular volume
 Transfusion may be needed after
initial resuscitation to keep
HCT > 20-25%
***Expensive

22. Pain Medications
 Avoid NSAIDs
 Opioids *critically ill patient
 Torb (Butorphanol) – 0.1-0.5 mg/kg,
IV, IM, SC q 2-6 hrs
 Buprenex (Buprenorphine) – 0.005-0.02 mg/kg,
IV, IM, SC q 4-12 hrs
 Hydromorphone – 0.05 to 0.2 mg/kg,
IV, IM q 1-4 hrs
 Injectable, varying effects (partial vs. full agonist)
 Partials better for respiratory compromised
 Reversible with Naloxone

23. Questions?