L11: Hypotension + Shock Flashcards
1
Q
First thing to do in a case of hypotension
A
give a small fluid bolus to check responsiveness
2
Q
____ determines systemic tissue perfusion, and normal values are _____-
A
Mean arterial pressure (MAP)
Normal: 60-80
3
Q
MAP=
A
CO x SVR
Inversely related per chart at end– if one is increased, the other is decreased to compensate, etc.
This is to keep MAP constant.
4
Q
Decreased systemic tissue perfusion might be due to either ____ or ____, which ______
A
Decrease CO and/or SVR
Determines the etiology of shock
5
Q
CO=
A
HR x SV
6
Q
SVR is influenced by
A
Vessel
length and diameter,
blood viscosity
7
Q
4 ways you can assess adequate global (brain) perfusion
A
Mental status
Urine Output (exception: renal failure pts)
Serum lactate/acidosis
Peripheral perfusion assessment
8
Q
The 3 stages of shock
A
- Pre-Shock
- Shock
- End-organ dysfunction
9
Q
Warm shock/compensated shock
Tachycardia, peripheral vasoconstriction, decreased blood pressure
A
Pre-shock
stage 1
10
Q
Compensatory mechanisms overwhelmed→ signs/symptoms of organ dysfunction
Tachycardia, dyspnea, metabolic acidosis, oliguria, confusion, cool clammy skin
A
Shock
stage 2
11
Q
Progressive end organ dysfunction→ irreversible organ damage, coma, death
A
End organ dysfunction
stage 3
12
Q
Is all hypotension an indicator of shock?
A
No
13
Q
5 Etiologies of Shock
A
Distributive=vasodilatory shock Hypovolemic Cardiogenic Neurogenic Obstructive
14
Q
Arterial lines may be placed in the ______ (3)
A
Radial artery
Brachial artery
Femoral artery
15
Q
Arterial lines are used for _______ and _______, but NOT used for ______
A
Used for:
Invasive arterial blood pressure monitoring
Recurrent ABGs
Not used for:
Medications
16
Q
Indications for a central line
A
delivery of caustic or critical medications and measurement of CVP
Appropriate for determining fluid status (CVP) and resuscitation in non-cardiogenic shock
17
Q
5 types of central lines
A
Triple lumen Double lumen Dialysis catheters Swan-Ganz Catheter PICC Line
18
Q
PICC line
A
Peripherally Inserted Central Line Catheter
Goes from arm→ heart
19
Q
Goes through heart and sits in pulmonary artery
Gives RA, RV, Pulmonary artery, or pulmonary artery wedge pressures depending on where it is
A
Swan-Ganz (PA) Catheter
20
Q
Most appropriate in cardiogenic shock→ improve patient outcomes
A
Swan-Ganz (PA) Catheter
21
Q
Central venous pressure (CVP)
A
5 – 15 mmHg
22
Q
Pulmonary capillary wedge pressure
PCWP
A
5-15 mmHg
23
Q
Cardiac Output (CO): blood flow/min
A
4-8 L/min
24
Q
Systemic vascular resistance (SVR)
A
1000-1500 dynes/sec/cm5
25
Clinical Presentation for ***ALL TYPES*** of shock
```
Hypotension
Tachycardia (except neurogenic)
```
****
Tachypnea
Oliguria
Mental status changes (confusion, lethargy)
Metabolic acidosis
****
Cool clammy skin (exception: early distributive and neurogenic shock)
Later: multi-organ failure, coagulopathy
26
Hypotension is defined as
SBP<90, or decreased in SBP of >40 mmHg
27
Who can compensate in shock for a while due to their increased CO?
Pregnant patients
28
Which kind of shock doesn't have tachycardia?
Exception: neurogenic shock = decreased HR
29
Which kind of shock doesn't have cool clammy skin?
Exception: early distributive and neurogenic shock have flushed, warm
30
inadequate intravascular volume→ decreased CO→ decreased oxygen delivery
Hypovolemic shock
31
Etiology of hypovolemic shock (2)
1. Blood loss (hemorrhagic)
| 2. Fluid loss
32
Causes of blood loss
Trauma
GI bleeding
Internal hemorrhage
Post-surgical
33
Causes of fluid loss
Dehydration
Protracted nausea, vomiting, diarrhea
Burns
Acute pancreatitis
34
Anytime you're taking care of a trauma patient, you must ______
rule out hemorrhagic shock first
35
Hypovolemic shock pathophysiology
Decreased blood volume (decrease preload due to intravascular volume loss) → decreased stroke volume→ decreased CO + BP
Decreased BP and volume→ impaired oxygen carrying capacity and inadequate tissue perfusion→ increased SVR to compensate for decreased CO
Switch from aerobic to anaerobic metabolism
Compensatory response→ decreased BP detected by
baroreceptors→ activation of the
sympathetic nervous system→ vasoconstriction→ blood is preferentially shunted and redistributed
36
Hemodynamic parameters in hypovolemic shock
```
HR: high
CVP: low
PCWP: low
CO: low
SVR: high
```
37
Cardiogenic shock symptoms
Chest pain, Dyspnea
| Palpitations, Fatigue
38
Cardiogenic shock signs
Tachycardia, tachypnea, hypotension
| Extremities: cool, clammy
39
Cardiogenic shock cardiac exam
JVP
| Heart sounds: muffled, new murmur, tachycardia
40
Main treatment for hypovolemic shock
Replace volume and/or blood products
41
Hemodynamic parameters for cardiogenic shock (including obstructive)
```
HR: high
CVP: high
PCWP: high
CO: low
SVR: high
```
42
Hemodynamic parameters for EARLY septic shock (and other vasodilatory causes: adrenal insufficiency, anaphylaxis, liver disease, medication)
```
HR: high
CVP: low
PCWP: +/-
CO: high or normal
SVR: low
```
43
Hemodynamic parameters for LATE septic shock
```
HR: high
CVP: low
PCWP: +/p
CO: low
SVR: high
```
44
Hemodynamic parameters for neurogenic shock
Everything is normal or low
| SVR: low
45
Main treatment for cardiogenic shock (including obstructive)
Fix underlying cause
Relieve obstruction (if needed)
Caution with fluids
+/- inotropes
46
Main treatment for early septic shock (and other vasodilatory causes: adrenal insufficiency, anaphylaxis, liver disease, medication)
Give fluids
Treat infection
Vasopressors
47
Main treatment for late septic shock
Treat infection
| Vasopressors
48
Main treatment for neurogenic shock
Neurosurgery
49
Early vs Late septic shock
| Early=warm shock
(Late=cold shock)
Both:
HR: high
CVP: low
PCWP: +/-
CO:
Early: high or normal
Late: low
SVR:
Early: low
Late: high
50
Hypovolemic shock presentation depends on
1. Amount of loss
2. Rate of loss
(slow can be compensated)
51
Main laboratory indicator of hypovolemic shock
```
***Lactate***
increases (>4) during
anaerobic metabolism,
derangements affecting O2 utilization and decreased hepatic clearance→ increased
mortality
```
52
Vasopressors should be used to treat hypovolemic shock IF:
If situation is dire SBP<70, use while restoring volume
| but this is a volume problem, so fixing that is #1
53
Hypovolemic shock symptoms
Hematemesis, hematochezia, melena
N/V/D
Abdominal pain
Evidence of trauma, Post-operative
54
Hypovolemic shock signs on exam
```
Physical signs
Dry oral mucosa
Hypotension, tachycardia, tachypnea,
Decreased JVP, CVP
*Decreased Urine Output*
Extremities: cool, clammy, decreased skin turgor
Confused
```
55
Don't ignore ______ because it's often the earliest indicator of hypovolemic shock
***Decreased urine output***
56
decreased CO secondary to heart failure
Cardiogenic shock
57
IF found, deviated trachea or crackles consistent with diffuse pulmonary edema would indicate ________
Cardiogenic origin of shock
58
Cardiogenic shock pathophysiolgoy
1. Pump failure→ decreased BP and decreased CO→ activation of the sympathetic nervous system
2. Hypotension and deceased CO→ decreased renal perfusion→ sodium and fluid retention
3. Secondary response: increased filling pressures
(CVP/PCWP) → volume overload in the lungs
4. Increased SVR to compensate for decreased CO
59
Possible etiologies of cardiogenic shock
Ischemia:
MI, cardiomyopathy
Valvular heart disease:
Ruptured papillary muscle or chordae tendineae, critical
AS, ventricular septum rupture
Arrhythmias:
Vfib, Vtach, complete heart block, Afib, Aflutter
OBSTRUCTIVE:
(extracardiac) (subclassification)
Massive PE, cardiac tamponade, tension pneumothorax
60
MI tx
O2, cath lab
61
Vtach/Vfib tx
ACLS
62
Tension pneumothorax tx
Decompression
63
Cardiac tamponade tx
Pericardiocentesis
64
First line inotrope for cardiogenic shock
Dobutamine +/- vasopressors
65
Distributive (Vasodilatory) Shock→ Decreased SVR
Etiologies:
```
Etiologies:
*Sepsis*
Adrenal insufficiency
Liver disease
*Anaphylaxis*
Drugs/medications
*Neurogenic*
```
66
Be cautious giving fluids in cardiogenic shock because _____
Hypotension and deceased CO→ decreased renal perfusion→ *sodium and fluid retention*
67
Tissues in septic shock have increased O2 demand due to
combating systemic infection
| and septic endotoxins
68
Get _____ labs for septic shock
*Lactate*
Cultures before abx:
blood x2, urine, sputum
69
***When should you suspect septic shock***
Suspect septic shock in the elderly or immunocompromised for unexplained hypotension, mental status changes, or signs of organ system dysfunction.
70
Pathophysiology of EARLY septic shock
Meet increased demand for oxygen by cells→ vasodilation→ decreased SVR→ hypotension→ detected by baroreceptors→ increased HR, contractility and CO.
Hyperdynamic response→ well compensated but difficult to maintain:
Circulating endotoxins aggravate cellular
hypoxia and exert toxic effects on the soft tissues and organs→ signs of organ impairment→ stampede:
pro-inflammatory cells outnumber anti-inflammatory cells.
“Malignant intravascular inflammation” → profound vasodilation
71
Pathophysiology of LATE septic shock
Capillary leakage and loss of vascular tone→
relative hypovolemia and hypotension→ further stimulate the sympathetic nervous system→ increased HR and SVR
Vasoconstriction→ compromised tissue perfusion aggravating cellular hypoxia→ to organ system malfunction:
Poor perfusion of the extremities
Poor perfusion of internal organs
72
Physical signs of septic shock
Fever, decreased BP, increased HR and RR
Extremities: warm (early), cool (late)
Confused (especially elderly)
73
*NEVER ignore _____*→ often the initial physiological response in septic shock
Tachypnea
74
First line vasopressor in septic shock
Norepinephrine
75
Acute, potentially life-threatening,
multisystem syndrome caused by the sudden release of mast cell mediators into the systemic circulation.
IgE mediated reactions
to foods, drugs, insect stings, or any agent capable of inciting a sudden, systemic
degranulation of mast cells
Anaphylaxis
76
Anaphylaxis presentation
Skin/mucosal involvement: hives, rash, itching/flushing, periorbital edema, lip edema, conjunctival swelling
Respiratory: nasal discharge/congestion, change in voice quality, sensation of “throat swelling”, stridor, shortness of breath, wheezing, cough
GI: N/V, diarrhea, crampy abdominal pain
CV: syncope, dizziness, tachycardia, hypotension
Death→ asphyxiation due to upper or lower airway
obstruction or from cardiovascular collapse/shock.
77
Main management of anaphylaxis
Start with the “ABCs!”
Oxygen, airway management
IM Epinephrine 1:1000 (1 mg/ml prep): 0.01mg/kg IM q 5-15 min PRN
78
Adjunct therapies for anaphylaxis
IV meds
H1 blocker (diphenhydramine)
H2 blocker (ranitidine)
+/- steroids (methylprednisolone)
79
Loss of sympathetic tone,
| leading to vasodilation, Bradycardia + hypotension
Neurogenic shock
80
Causes of neurogenic shock
Spinal cord injury
Disruption between brain and spinal cord
Closed head trauma
Injury to brain stem
81
Make sure to get ______ if you suspect neurogenic shock
X- rays→ Cervical spine (C7-T1 to clear the c-spine)
Head CT
R/o structural lesions, evidence of shift or
herniation
Spinal CT/MRI
82
Neurogenic shock pathophysiology
1. Sympathetics leave brain stem and travel down through
cervical spinal cord when they exit out the thoracolumbar
regions
2. Sympathetic nervous system is responsible for release of
epinephrine and norepinephrine, which cause increased HR,
myocardial contractility and peripheral vasoconstriction.
3. Disruption of sympathetic nervous system→ unopposed parasympathetic action
4. Hypotension with decreased SVR and normal to low HR
83
Neurogenic shock presentation
VS: HR normal/low, low BP
Neuro exam:
Mental status: +/- altered LOC
Motor exam: para-/quadriplegic
Sensory exam: depends on level affected
DTRs: absent/hyperreflexia
Extremities: warm (vasodilation)
Rectal exam: decreased sphincter tone
