recent concepts including scvo2, IVC collapsibility index, self descriptive figures, concepts made simpler.

1. PATHOGENESIS OF SHOCK

2. DEFINITION OF SHOCK
• PALS DEFINITION
Physiologic state characterized by inadeqaute
tissue perfusion to meet metabolic demand
and tissue oxygenation
Shock vs blood pressure vs cardiac output
- Shock can be present with normal, decreased
or increased BP.

3. Similarly shock can have low or high cardiac output
SHOCH – INADEQUATE SUPPLY OF NUTRIENTS,
INCREASED TISSUE DEMAND, OR COMBINATION
OF BOTH FACTORS.
Discussion – does not include for DKA, SAM,
dengue

4. Understanding Shock
• Inadequate systemic oxygen delivery activates
autonomic responses to maintain systemic
oxygen delivery
• Sympathetic nervous system
•NE, epinephrine, dopamine, and cortisol
release
•Causes vasoconstriction, increase in
HR, and increase of cardiac contractility
(cardiac output)

5. • Renin-angiotensin axis
•Water and sodium conservation and
vasoconstriction
•Increase in blood volume and blood pressure
• Cellular responses to decreased systemic oxygen
delivery
• ATP depletion → ion pump dysfunction
• Cellular edema
• Hydrolysis of cellular membranes and cellular
death

7. • Goal is to maintain cerebral and cardiac
perfusion
• Vasoconstriction of splanchnic,
musculoskeletal, and renal blood flow
• Leads to systemic metabolic lactic acidosis that
overcomes the body’s compensatory
mechanisms

8. Case scenario 1
1 yr old child, complaints of
• Loose stools – 8 to 10 episodes from 1 day,
• Vomiting - 3 to 4 episodes from past 4 hrs
• Decreased activity from past 4 hrs
• Decreasd urine output past 4 hrs

10. • ABCs
• Cardiorespiratory monitor
• Pulse oximetry
• Supplemental oxygen
• IV access
• ABG, labs
• Foley catheter
• Vital signs including rectal temperature
Approach to the Patient in Shock

13. Based on initial impression and primary
assessment, should be able to
• Recognise type of shock
• Stage of shock
• Intervene to halt progression of shock

14. Types of shock

16. PVR

20. Blood
pressure
low
Blood
pressure
normal
MODS

24. Repeating once again………..
• Single differentiating point
between compensated and
decompensated –
BLOOD PRESSURE
Of course, ScvO2

26. • Broadly classified into non hemorrhagic and
hemorrghagic
• Importance to recognise extent of volume
depletion and type to volume loss.
• Shock is usually present @ greater than 100
ml/kg of deficits.

28. Case scenario 2
2 yrs old with complaints of fever- 3 days
• Cough, wet type – 3 days
• Hurried breathing- 1 day
• Decreased activity- 1 day
• Decreased urine out -8 hrs
• O/E – febrile 102F, tachycaediac 140,
tachypneic 40, spo2 86, hypotension with
narrow pulse pressure

29. • Peripheral pulses- feeble volume,
not bounding ; central pulses – weak
• CRT- prolonged
• Extremities- pale, mottled ; central to
peripheral temp > 3 C
• RS- b/l crepts
• CNS- lethargic
What are we dealing with ????

30. Challenges in septic shock
1. Wide clinical spectrum – warm VS cold shock
2. Combination of hypovolemic, distributive and
cardiogenic shock
3. Early hypotension in septic shock
4. Variable degrees of inadequate perfusion and
microvascular thrombosis leading to ischemia
5. Adrenal insuffiency

34. Criteria for organ dysfunction

39. Concept of SCVO2
• Svo2 - measures venous oxygen saturation @
pulm artery.
• Scvo2 – measures venous oxygen saturation
@ superior venacava.
• Continuous ScvO2 monitoring triple-lumen
central venous catheter

40. Hallmark of uncompensated shock
If the body is unable to compensate
because of disease processes or
other physiologic problems, tissues
extract more than one oxygen
molecule, resulting in lower venous
oxygenation saturation as evidenced
by a decrease in ScvO2

41. Case scenario 3
12 yr old girl with h/o consumption of unknown
poisonous pellets, brought to ER
O/E – agitated, diaphoretic
Tachycardiac 120, hypotensive 80/62
spO2 – 86%, tachyneic with increased resp
efforts.
RS- b/l diffuse crepts; CVS- s1 and s2 normal
P/A – tender hepatomegaly

42. ECG – broad QRS complexes with features of
anterolateral wall MI
ABG- met acidosis with poor oxygenation
GRBS- 24, Serum Ca – 5 mg/dl, RFT – 43/1.21
S. Lactate levels- 15 mg/dl
DIAGNOSIS
Anterolateral MI with CCF with Cardiogenic
shock ?? Aluminum phosphide

43. Case scenario 4
4 day old term gestation male baby born to
NCM, apparently normal till 3 days, brought
with
Sudden onset resp distress- tachypneic with
retractions; Cyanotic, lethargic –from past 6
hrs
O/E- tachycardiac 180, spo2 –
CRT > 3 sec 80
86 82
78

44. Absence of femoral pulses, tender congested
hepatomegaly.
Metabolic acidosis with elevated lactate levels.
DIAGNOSIS-
Obstructive shock due to left ventricular
outflow obstruction ?? COA

45. Cardiogenic shock-
•CHD
•Myocarditis
•Cardiomyopathy
•Arrhytnmias
•Sepsis
•Myocardial injury
•Poisoning or drugs

46. Obstructive shock
• Cardiac tamponade
• Tension pneumothorax
• Duct dependent CHD
• Massive PE
• Abd compartment syndrome

48. Effusion around
the pump
Squeeze of the
pump
Strain of the
pump

49. Fullness of the
tank
Leakiness of the
tank
Tank compromise

50. Rupture of the
pipes
Clogging of the
pipes

51. IVC Assessment for Fluid
Responsiveness
1. Position the patient supine.
2. Obtain a subxyphoid view of the heart.
• The ultrasound indicator should be directed toward the
patient’s left flank.
3. Once identified the right atrium, turn the ultrasound
probe 90 degrees counterclockwise.
• The indicator should now be directed toward the
patient’s head.

52. 4. Identify the IVC as it enters the right atrium.
5. Put the ultrasound into M-mode.
6. Place the M-mode cursor cross the IVC
approximately 2 cm inferior to the junction
with the RA.

53. 7. In spontaneously breathing patients, the
following measurements suggest a patient is
likely to be fluid responsive:
• a. IVC measuring < 2 cm in diameter coupled
with IVC collapse
• > 50% with each breath or
• b. IVC collapsibility > 12%
IVC collapsibility = (max diameter – min diameter) /
(mean diameter) x 100

54. 8. In mechanically ventilated patients who are
passive on the venti, fluid responsiveness is
likely if the IVC distensibility > 18%.
IVC distensibility = (max diameter – min
diameter) / (min diameter) x 100