Shock

Question 1

Shock definition:

Answer 1

Inadequate oxygen delivery to meet metabolic demands… results in… global tissue hypoperfusion and metabolic acidosis

Question 2

Shock can/ can not occur with a normal BP:

Answer 2

Can

Question 3

Pathophysiology:

Answer 3

The lack of adequate energy supply leads to a build up of waste products and failure of energy-dependent functions, release of ccellular enzymes, accumulation of calcium and ROS -> cellular injury and cell death

Question 4

Stages of shock:

Answer 4

• Initial compensated stage - sympathoadrenal system, cortisol secretion, ACTH, vasopressin, RAAS, endothelin and vasoconstrictor production
• Decompensated reversible stage - organ damage symptoms appear - hypotension, hypoxia, tachypnea, oliguria, acidosis, altered mentation
• Decompensated irreversible stage - Multi-organ faliure

Question 5

Organ response (microcirculation):

Answer 5

Systemic vascular resistance rises - NE acts on a-1 receptors as a VC

Reduced filtration

Question 6

Organ response (cellular response):

Answer 6

Decreased ATP
Accumulation of H+, lactate

Question 7

Organ response (neuroendocrine response):

Answer 7

Vasoconstriction
Reduced vagal activity
ACTH release
Increased renin release

Question 8

Organ response (Cardiovascular response):

Answer 8

Decreased ventricular filling (decreased preload)
Impaired myocardial contractility which reduced SV
Elevated systemic vascular resistance

Question 9

Organ response (Pulmonary response):

Answer 9

Increased pulmonary vascular resistance (septic shock)
Tachypnoea but restricted ventilation
Atelectasis
ARSD

Question 10

Organ response (renal response):

Answer 10

Reduced renal blood flow and reduced GFR
Reduced urine volume, oliguria, ARF
Acute tubular necrosis

Question 11

Organ response (Inflammatory responses):

Answer 11

Activation of coagulation cascade causes microvascular thrombosis
TNF-a
IL-8
Thromboxan A2

Question 12

Compensation:

Answer 12

1. Mobilization of 11L interstitial fluids
2. SNS activation
3. RAAS activation, ADH secretion

Question 13

Types of distributive shock:

Answer 13

Septic
SIRS
Neurogenic
Anaphylatic
Drug-/toxin-induced
Endocrine

Question 14

Mild shock:

Answer 14

Loss of 10-15%
Collapse of subcutaneous vv. of extremities
Patient is thirsty and cold

Question 15

Moderate shock:

Answer 15

Loss of 20-30%
Mild tachycardia
Narrow pulse pressure
Tachypnea
Anxiety
Oliguria
Drowsy
Confused

Question 16

Severe shock:

Answer 16

Unconscious
Loss of >40%
Anuria
Rapid pulse
Hypotension

Question 17

ET Intubation can _____ hypotension

Answer 17

worsen

Question 18

Shock treatment goals:

Answer 18

BP (MAP>65mmhg)
CVP (8-12mmh2O)
Urine (>0.5ml/kg/hr)
Central venous O2 sat. > 70%, or mxed venous sat. >65%

Question 19

Maintain Hg>__d/l

Answer 19

10

Question 20

First step in treatment of shock:

Answer 20

Crystalloids 1000ml or
colloids 300-500ml in 30m

Question 21

Hypovolemic shock treatment:

Answer 21

Crystalloids
- normal saline or lactate ringers
- up to 2-2.5L
- Consider catecholamines

Question 22

Sepsis criteria:

Answer 22

HR > 90
RR > 20
WBC >12,000 or <4,000

Question 23

Sepsis initial treatment:

Answer 23

20-40mL/lg bolus

Question 24

Cardiogenic shock parameters:

Answer 24

SBP <90mmhg
CI < 2.2L/m/m2
PCWP > 18mmHg

Question 25

Loss of __% LV function causes clinical shock

Answer 25

40

Question 26

Intubation will ______ preload

Answer 26

decrease

Question 27

Anaphylaxis is ___ mediated

Answer 27

IgE

Question 28

How to distinguish anaphylaxis from anaphylactoid rxn clincally?

Answer 28

You can't dumbass

Question 29

Cause of anyphylactoid rxn?

Answer 29

Anasthetics, stings, food, AB

Question 30

Anaphylactic shock treatment?

Answer 30

0.3mg IM Epi-pen Repeat every 5-10mins as needed Caution w/ beta-blockers > HTN due to unopposed alpha stimulation CV collapse 1mg IV 1:10,000 If refractory, start IV drip

Question 31

Injury above __ can cause neurogenic shock

Answer 31

T1

Question 32

In neurogenic shock keep MAP at _______

Answer 32

85-90

Question 33

For blunt spinal cord injury consider

Answer 33

methylprednisolone

Question 34

Infusion of one litre of 0.9% NaCl adds ___mL to the plasma volume and ___mL to the interstitial volume

Answer 34

275 825

Question 35

Crystalloids

Answer 35

Contain electrolytes First line 25% in plasma, 75% in interstitial volume short HL: 30-60mins

Question 36

Colloids:

Answer 36

Large solute molecules do not pass readily from plasma to interstitial fluid 75% expands plasma volume 25% expands interstitial volume HL 2-4h Suitable for small-volume rescuscitation

Question 37

Indications for whole blood:

Answer 37

Hemorrhage (25% or more volume loss) Exchange transfusion Patients who bleed after 4 units of packed RBC's

Question 38

Indications for packed cell transfusion:

Answer 38

Symptomatic chronic anemia w/o hemorrhage Acute sickle cell crisis Cardiac faliure Acute blood loss Perioperative anemia

Question 39

Autologous vs Allogenic blood transfusion:

Answer 39

Autologous - same person Allogenic - another person