Presentation on Shock

DR. SHAHED IQBAL

Definition

SHOCK: Inadequate organ perfusion to meet

the tissue’s oxygenation demand.

Types of shock

Hypovolemic shock

Cardiogenic shock

Distributive shock

Obstructive shock

Septic shock

Decreased intravascular volume

Cardiac output

Shift of interstitial fluid

Aldosterone, ADH

Splenic dischargeVolume

Cardiac output

More volume loss

Tissue perfusion

Cardiac output

Impaired cellular metabolism

SVR, heart rate Catecholamine

release

Systemic and pulmonic

pressures

Disruption of sympathetic nervous system

Loss of sympathetic tone

Venous and arterial vasodilatation

Decreased venous return

Decreased stroke volume

Decreased cardiac output

Decreased cellular oxygen supply

Impaired tissue perfusion

Impaired cellular metabolism

Pathophysiology of Neurogenic

Shock

Antigen (allergen)Antibody (IgE)

Complement, histamine,

Kinins, prostaglandins

Capillary permeability

Tissue perfusion

Extravasation of

intravascular fluidsSVR

Edema

Peripheral

Vasodilation

Relative hypovolemia

Cardiac Output

Impaired cellular

metabolism

Constriction of extravascular

Smooth muscle (bronchoconstriction

Larygospasm, gastrointestinal

Cramps)

METABOLISM

AEROBIC METABOLISM

6 O₂

GLUCOSE

6 CO₂

6 H₂O

36 ATP

HEAT (417 kcal)

GLUCOSE

HEAT (32 kcal)

2 ATP

2 LACTIC ACID

ANAEROBIC METABOLISM

METABOLIS

M

ANAEROBIC? So What?

Inadequate

Energy

Production

Anaerobic

Metabolism

Lactic Acid

Production

Metabolic

Failure Cell Death!Metabolic

Acidosis

Inadequate

Cellular

Oxygenation

PATHOPHYSIOLOGY OF SHOCK SYNDROME

Cells switch from aerobic to anaerobic metabolism

lactic acid production

Cell function ceases & swells

membrane becomes more permeable

electrolytes & fluids seep in & out of cell

Na+/K+ pump impaired

mitochondria damage

cell death

Compensated

The body’s compensatory mechanisms are able

to maintain some degree of tissue perfusion.

Decompensated

The body’s compensatory mechanisms fail to

maintain tissue perfusion (blood pressure falls).

Irreversible

Tissue and cellular damage is so massive that the

organism dies even if perfusion is restored.

Stages of Shock

• Inadequate systemic oxygen delivery activates autonomic

responses to maintain systemic oxygen delivery

• Sympathetic nervous system

• NE, epinephrine, dopamine

• Causes vasoconstriction, increase in HR, and increase of cardiac contractility

(cardiac output)

• Renin-angiotensin axis

• Water and sodium conservation and vasoconstriction

• Increase in blood volume and blood pressure

Compensate ? How?

Hormonal: Antidiuretic Hormone

Osmoreceptors in hypothalamus stimulated

ADH released by Posterior pituitary gland

Vasopressor effect to increase BP

Acts on renal tubules to retain water

COMPENSATION CONTINUE

SEPTIC SHOCK

CardiogenicDistributive

Hypovolemic

Insult, injury or infection

Local inflammatory reaction

Release of mediators

Systemic inflammatory response

Diffuse endothelial injury,

vasodilatation

and increased capillary permeabilityProgressive vasodilatation and maldistribution of blood flow

Organ hypoperfusion

Multiple organ dysfunction syndrome

PATHOGENESIS OF SEPTIC SHOCK

Sepsis or tissue hypoxia with lactic acidosis

Nitric oxide synthase ATP, H⁺, lactate

In vascular smooth muscleVasopressin secretion

Nitric oxide

Open Kca

cGMP Cytoplasmic Ca²⁺

Phosphorylated myosin

Vasodilation

Open KᴀᴛᴘVasopressin stores

Plasma

Vasopressin

CRITERIA FOR ORGAN DYSFUNCTION

Cardiovascular

Respiratory

Neurologic

Hematologic

Renal

Hepatic

Despite administration of isotonic intravenous fluid bolus > 60

ml/kg in 1 hour: Decrease in BP ( hypotension) <5th percentile

for age or systolic BP <2 SD below normal for age

OR

Need for vasoactive drug to maintain BP in normal range

(dopamine>5μg/kg/min or dobutamine,epinephrine,or

norepinephrine at any does)

OR

Two of the following:

Unexplained metabolic acidosis: base deficit >5.0 mEq/L

increased arterial lactate:>2X upper limit of normal

Oliguria: urine output <0.5ml/kg/hr

Prolonged capillary refill:>5 sec

Core to peripheral temperature gap >3⁰C

Cardiovascular

MAP <5th PERCENTILE FOR AGE

LOWEST ACCEPTABLE SBP = 70 + [2x AGE IN YEARS]

AGE LOWEST ACCEPTABLE SBP

TERM NEONATE 60

INFANT 1-12 MONTHS 70

CHILDREN 1-10 YRS 70 +[2x AGE IN YEARS]

CHILDREN >10 YRS 90

HYPOTENSION

• Do you remember how to

quickly estimate blood

pressure by pulse?

60

80

70

90

• If you palpate a pulse,

you know SBP is at least this number

Shoc

k

Pa0₂/Fi0₂ ratio <300 in absence of cyanotic heart disease or

pre-existing lung disease

OR

PaC0₂ >65 torr or 20 mm Hg over baseline PaC0₂

OR

Proven need for >50% Fi0₂ to maintain saturation >92%

OR

Need for nonelective invasive, noninvasive mechanical

ventilation

Respiratory

GCS Score <11

OR

Acute change in mental status with a decrease in GCS score

>3 points from abnormal baseline.

Neurologic

EYE OPENING

SPONTANEOUS 4

TO VOICE 3

TO PAIN 2

NONE 1

VERBAL RESPONSE

OLDER CHILDREN INFANTS & YOUNG CHILDREN

ORIENTED 5 APPROPIATE WORDS; SMILE,

FIXES,FOLLOWS

5

CONFUSED 4 CONSOLABLE CRYING 4

INAPPROPIATE 3 PERSISTENTLY IRRITABLE 3

INCOMPREHENSIBLE 2 RESTLESS, AGITED 2

NONE 1 NONE 1

MOTOR RESPONSE

OBEYS 6

LOCALIZES

PAIN

5

WITHDRAWS 4

FLEXION 3

EXTENSION 2

NONE 1

Platelet count <80,000/mm³ or a decline of 50% in the platelet

count from the highest value recorded over the last 3 days (for

patients with chronic hematologic or oncologic disorders)

OR

INR>2

Hematologic

Serum creatinine >2X upper limit of normal for age or 2-fold

increase in baseline creatinine value

Renal

Total bilirubin >4 mg/dL (not applicable for newborn)

Alanine transaminase level 2x upper limit of normal for age.

Hepatic

INTERNATIONAL CONSENSUS

DEFINITIONS

FOR

PEDIATRIC SEPSIS

MODS

INFECTION

SIRS

Sepsis

Severe Sepsis

Septic Shock

MODS

Suspected or proven infection or a clinical syndrome

associated with high probability of infection

INFECTION

2 out of 4 criteria, 1 of which must be abnormal temperature

or abnormal leukocyte count:

1. Core Temperature >38.5°C or <36°C

(rectal, bladder, oral, or central catheter)

2. Tachycardia:

Mean heart rate >2 SD above normal for age in

absence of external stimuli, chronic drugs or painful

stimuli

OR

Unexplained persistent elevation over 0.5-4 hr

OR

In children <1 year old, persistent bradycardia over 0.5

hour (mean heart rate <10th percentile for age in absence

of vagal stimuli, β-blocker drugs, or congenital heart

disease)

Systemic inflammatory response syndrome (SIRS)

Systemic inflammatory response syndrome (SIRS)

3. Respiratory rate >2 SD above normal for age or acute

need for mechanical ventilation not related to

neuromuscular disease or general anesthesia

4. Leukocyte count elevated or depressed for age (not

secondary to chemotherapy) or >10% immature

neutrophils

SIRS plus a suspected or proven infection

Sepsis

Sepsis plus 1 of the following:

1. Cardiovascular organ dysfunction, defined as:

Despite >40 ml/kg of isotonic intravenous fluid in 1 hour:

Hypotension <5th percentile for age or systolic blood pressure <2 SD

below normal for age

OR

Need for vasoactive drug to maintain blood pressure

OR

2 of following:

Unexplained metabolic acidosis: base deficit >5 mEq/L

Increased arterial lactate: > 2 times upper limit of normal

Oliguria: urine output <0.5 ml/kg/hr

Prolonged capillary refill:> 5 sec

Core to peripheral temperature gap >3°C

Severe Sepsis

2. Acute respiratory distress syndrome (ARDS) as defined by the

presence of a PaO₂/Fi₀₂ ratio ≤300 mm Hg, bilateral infiltrates on

chest radiograph, and no evidence of left heart failure.

OR

Sepsis plus 2 or more organ dysfunctions (respiratory, renal, neurologic,

hematologic, or hepatic)

Severe Sepsis

Sepsis plus cardiovascular organ dysfunctions as defined above

Septic Shock

Presence of altered organ function such that homeostasis cannot be

maintained without medical intervention.

Multiple organ dysfunction syndrome (MODS)

Clinical diagnosis of septic shock

Suspected infection

Decreased perfusion

altered mental status

decrease urine output

prolong CRT or flash CR

diminished or bounding peripheral pulses

mottled cool extremities

What is the first physiological factor in the development of

shock?

?

So, what are the first symptoms you would expect to find?

↑ respiratory rate

↑ heart rate

Clinical Findings

What is often the second physiological response to

the development of shock?

Peripheral vasoconstriction

What symptoms would you expect to see?

pale skin

cool skin

weakened peripheral pulses

Clinical Findings

As shock progresses, what physiological effects are seen?

End-organ perfusion falls

What symptoms would you expect to see?

altered mental status

decreased urine output

Clinical Findings

As compensatory mechanisms fully engage, what signs

and symptoms would you expect to see?

tachycardia

tachypnea

pupillary dilation

decreased capillary refill

pale cool skin

Clinical Findings

When compensatory mechanisms fail, what signs and symptoms would you expect to see?

hypotension

falling SpO2

bradycardia

loss of consciousness

dysrhythmias

Mods

Clinical

Findings

Cold Shock Warm Shock

Heart rate Tachycardia Tachycardia

Peripheries Cool Warm

Pulses Difficult to palpate Bounding

Skin Mottled, pale Flushed

Capillary refill Prolonged Blushing

Mental state Altered Altered

Urine Oliguria Oliguria

Recognize

ShockCold Shock

Skin and extremities:

Cool

Pale

Mottled

Cyanotic

Poor cap refill

Recognize

ShockWarm Shock

Skin and extremities:

Warm

Flushed

Flash Capillary Refill

Recognize

ShockPoor Capillary Refill

Anything longer than

2 seconds is delayed

If you get as far as 5 sec,

you’d better be calling for help

Blood Count & film

Anemia

Leucocytosis

Leucopenia

Neutropenia

Thrombocytopenia

Immature Neutrophil

Vaculation of neutrophil

Toxic granulation

Döhle Bodies

Blood Culture

Lab Results

Blood Glucose

CRP

Lab Results

LFT

↑ PT, PTT

↑ SBR

↑ ALT

↓ ALB

RFT

Urine R/E

Urine C/S

Creatinine

Electrolyte

CXR

ABG

HEMODYNAMIC VARIABLES IN DIFFERENT SHOCK STATES

TYPES OF

SHOCK

CARDIA

C

OUTPU

T

SYSTEMIC

VASCULAR

RESISTANC

E

MEAN

ARTERIAL

PRESSURE

CAPILLARY

WEDGE

PRESSURE

CENTRAL

VENOUS

PRESSURE

HYPOVOLEM

IC

↓ ↑ ↔ OR↓ ↓↓↓ ↓↓↓

CARDIOGENI

C

SYSTOLIC

↓↓ ↑↑↑ ↔ OR↓ ↑↑ ↑↑

DIASTOLIC

↔ ↑↑ ↔ ↑↑ ↑

OBSTRUCTIV

E

↓ ↑ ↔ OR↓ ↑↑ ↑↑

DISTRIBUTIV

E

↑↑ ↓↓↓ ↔ OR↓ ↔ OR↓ ↔ OR↓

SEPTIC

EARLY

↑↑↑ ↓↓↓ ↔ OR↓ ↓ ↓

↓↓ ↓↓ ↓↓ ↑ ↑OR↔

HEART RATE, RESP RATE AND BLOOD PRESSURE

VALUES BY AGE

AGE HEART

RATE/MIN

RESPIRATORY

RATE/MIN

SBP

NEONATE 120-180 40-60 60-80

1M-1YEAR 110-160 30-40 70-90

1-2YEAR 100-150 25-35 80-95

2-7YEAR 95-140 25-30 90-110

7-12YEAR 80-120 20-25 100-120

Fluid-refractory Shock:

Shock despite 60 cc/kg in 1st hour

Dopamine-resistant Shock:

Shock despite adequate fluid resuscitation and 10

mcg/kg/minCatecholamine-resistant Shock:

Shock despite epinephrine or norepinephrine

Refractory Shock:

Shock despite goal-directed use of inotropic

agents, vasopressors, vasodilators, and

maintenance of metabolic and hormonal

homeostasis