shock lecture.ppt

shock lecture.ppt

1. SHOCK
Objectives: at the end of this
lecture you would be able to :
1-define shock
2-recognize types of shock and their causes
3-correlate pathophysiologicchanges with
clinical features .
4-know the broad lines of monitoring and
treatment of shock patients .

2. Shock
A physiological state characterized
by a significant, systemic reduction
in tissue perfusion, resulting in
decreased tissue oxygen delivery and
insufficient removal of cellular
metabolic products, resulting in
tissue injury.

3. Shock is not a synonym to hypotension!
SHOCK
Definition:
SHOCKisanacutecirculatoryfailure,
characterizedbydysfunctionofthe
microcirculation,inadequatebloodflowto
vitalorgansandinabilityofthebodycell
masstometabolizethenutrientsnormally.

4. Whatarethefunctionsofthe
cardio-vascularsystem?

5. Definition of Shock
Cellular level:
Reduction of mitochondrial oxygen
Anaerobic glycolysisof ATP
Accumulation of pyruvateLactaticAcidosis

6. SHOCK
Classification of Shock
A-Classification of Shock by Causes
(1) Hypovolemicshock
(2) Cardiogenicshock
(3) Neurogenicshock
(4) Anaphylactic shock
(5) Septic shock

7. B. Classification of Shock according to
hemodynamic changes:
⑴HypodynamicShock: Cardiac Output ,
Vascular Resistace,
Cold Skin;
⑵HyperdynamicShock: Cardiac Output ,
Vascular Resistace,
Warm Skin;

8. Metabolic Disturbances
Inadequate Blood Flow
Circulatory Failure
Different kind of Reason
Special Clinical Syndrome

9. Low blood flow
Skin,fat,skeletal
muscls,kidney,intestines
Heart,brain normal or
Systemic pathophysiologic responces of Shock
Redistribution of blood flow

10. Etiology & Hemodynamic
Changes in Shock
VO2satSVRCOCVPexampleEtiology of
shock
lowhighlowlowhypovolemicpreload
lowhighlowhighcardiogeniccontractility
distributiveafterload

11. Etiology & Hemodynamic Changes
in Shock (Afterload)
VO2 SATSVRCOCVPEXAMPLEETIOLOGY
OF SHOCK
DISTRIBUTIVEAFTERLOAD
HighLowHighLow/HighHyperdynamic
Septic
Low/HighHighLowLow/HighHypodynamic
Septic
LowLowLowLowNeurogenic
LowLowLowLowAnaphylactic

12. HypovolemicShock
Decreased preload→smallventricular end-
diastolic volumes →inadequate cardiac
generation of pressure and flow
Causes:
--bleeding: trauma, GI bleeding, ruptured
aneurysms, hemorrhagic pancreatitis
--protracted vomiting or diarrhea
--adrenal insufficiency; diabetes insipidus
--dehydration
--third spacing: intestinal obstruction,
pancreatitis, cirrhosis

13. Classes of acute hemorrhage
Class I Class II Class IIIClass IV
Blood
loss
< 750 cc
0-15%
750-1500
15-30%
1500-2000
30-40%
>2000cc
>40%
HRNormal
PPNormal
BPNormal Normal
UOP Normal Normal DecreasedNegligible
MentalNormal Anxious Confused Lethargic
FluidCrystalloidCrystalloidCrys+bloodCrys+blood
*ATLS; 2004. 70kg male

14. Signs & Symptoms:Hypotension, Tachycardia,
change, Oliguria, DeminishedPulses.
Markers: monitor urine output UOP, central
venous pressure CVP, blood pressure BP, heart
rate HR, hemaocritHct, mental state MS,
cardiac outputCO, lactic acid and pulmonary
capillary wedge pressurePCWP
Treatment: IVF (crystalloid), Trasfusion,
Stem ongoing Blood Loss

15. TRUE OR FALSE ?
The earliest sign of hypovolemic
shock is hypotension .

16. TRUE OR FALSE
In early stage of hypovolemic
shock the skin would be warm
due to vaso-dilation .

17. Septic/InflammatoryShock
This type is due to infection/sepsis: G(-/+ )
speticemia, pneumonia, peritonitis, meningitis,
cholangitis, pyelonephritis, necrotic tissue,
pancreatitis, wet gangrene, toxic shock
syndrome, etc.
Mechanism:
It is due to release of inflammatory mediators
which leads to
1-Disruption of the microvascular endothelium
2-Cutaneous arteriolar dilation and sequestration
of blood in cutaneous venules and small veins

18. Signs:
Early–warm with vasodilation(hyper dynamic
circulation), often adequate urine output, fever and
tachypnea.
Late--vasoconstriction, hypotension, oliguria,
altered mental status (hypodynamiccirculation).
Findings:
Early: hyperglycemia, respiratory alkalosis,
hemoconcentration, WBC typically normal or low.
Late: Leukocytosis, lactic acidosis
VeryLate:Disseminated Intravascular Coagulation &
Multi-Organ System Failure.

19. Treatment:
Intravenous fluid IVF, Blood
transfusion, antibiotics, Drainage (ie
abscess) vasopressoragents .

20. TRUE OR FALSE
In hyperdynamicstate of septic
shock there is rapid washout of
metabolites because of increased
blood supply to the tissues

21. CardiogenicShock
Mechanism: Intrinsic abnormality of heart →
inability to deliver blood into the vascular
tree with adequate power
Causes:
1. Cardiomyopathies: myocardial ischemia,
myocardial infarction, cardiomyopathy,
myocardiditis, myocardial contusion
2-Mechanical: cardiac valvularinsufficiency,
papillary muscle rupture, septaldefects,
aortic stenosis

22. 3-Arrythmias: bradyarrythmias(heart
block), tachyarrythmias(atrial
fibrillation, atrialflutter, ventricular
fibrillation)
4-Obstructive disorders: pulmonary
embolism PE, tension peneumothorax,
pericardial tamponade, constrictive
pericaditis, severe pulmonary
hypertension

23. Signs and symptoms : Dyspnea, rales, gallop, low
BP, oliguria
Monitor/findings: CXR pulmonary venous
congestion, elevated CVP, Low CO.
Treatment : this will be according to cause eg
Congestive heart failure CHF–diuretics &
vasodilators +/-pressors.
Left ventricular LV failure –pressors,
decrease afterload, intraaorticballonpump &
ventricular assist device.

24. Neurogenic Shock
Mechanism: Loss of autonomic innervation
of the cardiovascular system (arterioles,
venules, small veins, including the heart)
Causes:
*Spinal cord injury
*Regional anesthesia
*Drugs
* Neurological disorders

25. Characterized by loss of vascular
tone & reflexes.
Signs: Hypotension, Bradycardia,
Accompanying Neurological
deficits.
Treatment : IVF, vasoactive
medications if refractory

26. Anaphylactic shock:
This type occurs due to binding of a foreign
antigen to immunogloinE (IGE) on the
mast cells and basophils, releasing large
amounts of histamineand SRS-A( slow-
release substance-anaphylaxis) which will
produce bronchospasm, laryngeal edema
and respiratory distress with hypoxia ,
massive vasodilatation hypotension and
shock.Thistype occurs on exposure to
penicillin, anestheticdrugs, serum
injectionsand stings.

27. Monitoring of shock
1-General monitoring
Heart rate
Breathing

28. Monitoring of shock
2．Colour and temprature
of skin

29. Monitoring of shock
3．BP
Systolic Pressure was
lower than 12kPa(90mmHg)
4. Urina
Oliguria

30. Special monitoring
1.CVP 5-10cmH2O
CVP<5cmH2O Inadequecyof blood volume
CVP>12cmH2O Cardiac dysfunction
2.Lung arterial pressure
3.Cardiac output
4.Blood gas PO275-100mmHg
Pco240mmHg
PH 7.35—7.45
5.Coagulation test
Monitoring of shock

32. Treatment of the shock
Position of Body 30。

33. TRUE OR FALSE
* shock in intestinal obstruction
is multifactorial.