1. Shock

2. Anatomy and Physiology of Cardiovascular System
CO = SV * HR (Normal = l/min)
MAP = Dist. Pressure + 1/3 Pulse Pressure (Normal = mmHg)
Preload (volume)
After load (SVR)
Contractility

3. Shock
It is a state of generalized cellular hypoperfusion in which delivery of oxygen at the cellular level is inadequate to meet metabolic needs.

4. Signs and Symptoms of Shock
Decreased LOC, anxiety, disorientation.
Tachycardia, decreased SBP and pulse pressure
Rapid shallow breathing
Cold, pale, clammy, diaphoretic, cyanotic skin, decreased capillary refill time.
Decreased urine output

5. Classification of Shock
Hypovolemic shock (blood)
Distributive shock (vasogenic)
Cardiogenic (heart)

6. Severity of Shock
Compensated shock: patient is developing shock but body still able to maintain perfusion.
Decompensated shock: patient developed shock but body no longer can compensate.
Irreversible shock: patient developed shock but body is unable to maintain perfusion to organs.

7. Hypovolemic Shock
It is the most common cause of shock in trauma patients.
Causes:
External: bleeding (trauma), GI bleeding, ruptured aneurysms, hemorrhagic pancreatitis. vomiting or diarrhea, adrenal insufficiency, diabetes insipidus, dehydration
Internal: third spacing: intestinal obstruction, pancreatitis, cirrhosis

8. Hypovolemic Shock Markers: UOP,CVP, BP, HR, Hct, CO
Treatment: ABCs, IVF (crystalloid), Blood Transfusion.
Patients on β-blockers, or with spinal shock & athletes may not be presented with tachycardia.

9. Categories of Hemorrhagic Shock
Class I
Class II
Class III
Class IV
Blood Loss %
< 750 ml
< 15 %
ml (15-30 %) ml
(30-40 %)
> 2000 ml
> 40 %
HR (b/min)
Normal or minimally ↑
> 100
> 120
> 140
Ventilatory R. (breath/min)
Normal
20 – 30
30 – 40
> 35
SBP
Decreased
Greatly Decreased
Urine Output
(ml/hr)
5 – 15
Minimal

10. Distributive (Vasogenic) Shock
It occurs when vascular container enlarges without a proportional increase in fluid volume.
Septic Shock
Neurogenic Shock
Psychogenic (vasovagal) Shock

11. Septic Shock
Caused by cytokines release in response to infection, sepsis: G(-/+ ) septicemia, e.g. pneumonia, peritonitis, etc.
S & S: cool, clammy, pale, mottled skin, BP drop, altered LOC, slowed capillary refill.
Markers: Temp, WBC count, …
Rx: ABCs, IVF, Drainage (ie abscess).

12. Neurogenic Shock
It occurs when injury interrupts the spinal cord sympathetic nervous system pathway.
S & S: warm, dry, pink skin, bradycardia, BP drop, lucid LOC, normal capillary refill.
Rx: IVF, vasoactive medications if refractory

13. Psychogenic Shock
It is mediated through parasympathetic nervous system. (stimulation of vagal nerve)
It is temporary state lasts for few minutes.

14. Cardiogenic Shock Failure of the heart’s pumping activity.
Intrinsic Causes:
Heart muscle damage
Dysrhythmia
Valvular disruption
Extrinsic Causes:
Cardiac tamponade
Tension pneumothorax

15. Cardiogenic Shock
S & S: cool, clammy, pale, cyanotic skin, BP drop, altered LOC, slowed capillary refill.
Markers: CXR, CVP, CO.
Rx: diuretics & vasodilators +/- pressures, decrease after load, intraaortic balloon pump

16. Complications of Shock
Acute Renal Failure
Acute Respiratory Distress Syndrome
Hematologic Failure
Hepatic Failure
Multiple Organ Failure

17. Volume Resuscitation Enteral Route Vascular Access Intravenous route
Intraosseous route

18. Intravenous Solutions
Crystalloids Solutions
Hypotonic solutions
Isotonic solutions
Hypertonic solutions
Colloids Solutions
Blood Substitutes

19. Colloids
High molecular weight substances so do not cross capillary membranes.
Used as volume or plasma expanders
They include:
Albumin
Hetastarch
Dextran

20. Blood
It is given as packed RBCs, which should be cross-matched, but in an urgent situation, 1 to 2 units of type O Rh-negative blood are an acceptable alternative.
When > 1 to 2 units are transfused (eg, in major trauma), blood is warmed to 37° C.
Patients receiving > 8 to 10 units may require replacement of clotting factors with infusion of fresh frozen plasma or cryoprecipitate and platelet transfusion.