shock Flashcards
what is shock
Impaired O2 delivery/utilization
Increased O2 consumption
asymmetry in supply and demand
why do we care about shock
hypo-perfusion
When it becomes irreversible (cells start to die) > multi-organ failure and death
what decreases supply
Pump failure
Decreased total blood volume
Poor vascular tone (vessels can’t be leaky)
What can increase demand?
Exercise
Infection
Meds/toxins
Hypermetabolic states (hyperthyroidism, pregnancy, anemia)
poor vascular tone
leaky blood vessels
kidney failure looks like
increase in Cr
fluid retention
(urine output is decreased)
might need a catheter
loss of perfusion to the brain looks like
altered mental state agitation loc confusion intracerebral bleeding coma
loss of perfusion to the lungs can result in
acute respiratory distress
drugs that cause shock
prescription medications
toxins
BP
CO times SVR (systemic vascular resistance)
co
SV (amt of blood you are pushing out)
times HR
anaphylaxis and toxins have a direct effect on
SVR (systemic vascular reserve)
What happens when we don’t have O2
We go through the process of fermentation. We get a build up of lactate
what happens when you get a lactic acid build up?
You get lactate build up bc it disrupts the electrolyte balances in the cell. We see influx of Ca++ and it triggers a process called apoptosis.
respiratory complications of
tachypnea
SOB
can go into ARDS
(lungs fill with fluid and lungs are crying bc they are not getting enough oxygen),
The normal blood lactate concentration in unstressed patients is
0.5-1 mmol/L.
something around 2
Early sign shock
MAP decreased 10 mmHG
effective compensation
O2 is still getting to vital organs and
increased heart rate
what are compensatory signs
MAP down 10-15 mm Hg
increased RENIN and ADH
–>vasoconstriction
decreased PP increased HR decreased pH restless apprehensive
progressive signs (intermediate)
decreased MAP 20 mm Hg
tissue organ hypoxia
decreased UO
decreased pH
weak rapid pulse
sensory changes
refractory signs irreversible
excessive cell organ damage
multisystem failure and decreased pH
this is where you start to see cellular damage. Kidneys start to fail
Progressive signs of shock
Coagulation of shock
PT/INR will be elevated, DIC is present (purpura, INR will be through the roof)
effect on kidneys
decreased urine output, get creatinine
cardiac markers of shock
tachycardia, chest pain, EKG disturbances
Liver effects
hypotensive, LFTs (AST/ALT in the 1000s –> this is shock liver), bilirubin and albumin can be high
your vascular tone is failing (leaky blood vessels)
i. Distributive shock
Distributive shock what is happening
Something is telling them to dilate and it causes leakage of nutrients into the interstitium. So even though your blood volume is good, your blood vessels are leaky so they are not getting the nutrients
SUPPLY
hypovolemic
not enough gas in your tank. Pump is working and vascular tone is good but don’t have enough volume
SUPPLY
Cardiogenic shock
DEMAND
pump failure can’t get the blood where it needs to be
NO FLUIDS
fluid in lungs–> need to intubate–> sedation drops pressure–> coding
obstructive shock
SUPPLY
everything is working but there is something blocking and you’re not getting O2
peritoneal signs of hypovolemic shock
rigid abdomen
blood is irritating
hemorrhagic hypovolemic shock can look like
- Trauma
- GI Bleed
- AAA rupture
- Ruptured ectopic pregnancy (call the OB)
- Post-partum hemorrhage
hypovolemic tx can look like
pressor
fluids
blood
Non-hemorrhagic causes of hypovolemic (4)
- GI loss (vomiting/diarrhea)
- Inadequate intake
- Environmental/neglect
- Burns
if you loose 700 mL of blood or 15% BV you are what class of shock
class I
normally HR increased
class 3 of shock
1500-2000 loss of 30-40% BV HR >120 RR 30-40 decreased systolic blood pressure urine output decreased 5-15 mL
class 2 of shock
750-1500 15-30% >100 20-30 rr NORMAL bp
20-30mL UO
class IV of shock
>2000 mL >40% >140 >35 RR greatly decreased systolic BP UO minimal
in hypovolemic shock you want to start IV with a
crystalloid
maybe colloid for cardiac and pulmonary complications
TX of hypovolemic shock
- ABCs
- Good IV access
- VOLUME – start with crystalloid
- Blood if bleeding (massive transfusion protocol)
- Pressors - Norepinephrine
- Definitive management (stop bleeding, OR/endoscopy if needed, treat underlying condition)
71 y/o M, hx of HTN, DM, prior stents with CP/SOB/dizziness/weakness for the last 5 hours
VS: 96.2 104 72/50 27 91% 4L NC
what type of shock would you suspect
i. Ill appearing, dyspneic
ii. Tachycardic
iii. Crackles in both lungs
iv. 2+ pitting edema to knees bilaterally
cardiogenic shock picture
need an ECG
bedside echo
causes of cardiogenic shock (5)
MI or infarction valvular disease cardiomyopathy myocarditis toxins
Tx of cardiogenic shock
i. ABCs (C also for Call Cardiology!!)
ii. Oxygenation/Intubation
iii. IV access
iv. Careful fluid resuscitation
v. Inotropes/Vasopressors (Dobutamine/Norepinephrine)
vi. Definitive management (cath lab for stent/balloon pump vs. OR for CABG/valve replacement)
a. A 23 y/o healthy M presents with weakness, chills, nausea and abdominal pain for 3 days
b. VS: 103.2 117 71/45 22 100% on RA
c. Exam
i. Ill appearing, +rigors
ii. Dry MM
iii. Abdomen uncomfortable to palpation, particularly in the lower quadrants, +rebound/guarding
i. WBC 29
ii. Creatinine 2.9
iii. Lactic acid 4
iv. UA: no signs of infection
distributive shock
WBC normal
4.5-11
normal creatinine
.8-1.4
reasons for distributive shock
septic shock
anaphylactic shock
neurogenic shock
what is the reason for septic shock
Overwhelming systemic infection
common causes of Anaphylactic shock
a. Food
b. Medication
c. Contrast
d. Insects
reasons for neurogenic shock
spinal cord injury is an example
in general how should we treat distributive shock
- ABCs
- IV access
- Fluids
- Vasopressors (Norepinephrine)
septic shock tx
- Look for source!
- Antibiotics (broad)
- Source control (surgery if needed)
anaphylactic shock tx
- Epinephrine (0.3mg IM)
- Steroids
- H1/H2 blockers
- Decontamination
neurogenic shock tx
- C collar/stabilize spine
- Atropine/pressors
- Steroids controversial
- NSG intervention
what would obstructive shock look like on a ecg
on CXR
on echo
low voltage
CXR shows – cardiomegaly
ECHO shows — large pericardial effusion w/ cardiac tamponade
causes of obstructive shock
- Cardiac tamponade
- Tension pneumothorax
- Pulmonary embolism
- Severe aortic stenosis
how does Cardiac tamponade create shock
TX
Tamponade = can’t fill the heart
Obstruction = pericardial effusion
• Pericardiocentesis
how does tension pneumothorax cause shock
can’t fill the heart
Obstruction = air in chest; with mediastinal shift and tracheal deviation
• Chest tube
Pulmonary embolism as a cause of shock
can’t fill the heart
a. Obstruction = large clot in PA
• Thrombolytics/anticoagulation
Severe aortic stenosis
can’t pump out into aorta
a. Obstruction = stenotic aortic valve
• Valve replacement
what does a pt in shock look like ?
i. Ill appearing
ii. Abnormal vitals (hypotension, tachycardia)
iii. Weak pulses
iv. Mental status changes
v. Cool/clammy extremities
what does assessment look like in a pt with shock
i. BP (?Art line/central line for CVP)
ii. Lactate clearance
iii. Hemoglobin (>10)
iv. Urine output (>0.5 ml/kg/hr)
SNS neurotransmitters
noraderenaline and adrenaline
B1 receptor
both increases heart rate and contractility and speed
B2
stimulation leads to vasodilation
A1
stimulation causes vasoconstriction
catecholamine release that in response to a drope in CO
epinephrine
norepinephrine
septic shock
LPS toxins cause
nitric oxide release from cell damage
compliment cascade triggered causing mor vasodilation
TNF causes more release of inflammatory chemicals
damagining the endothelial cells and making them leaky
procoagulant-TF also released leads to clotting and bloackages and further decreased profusion
how does distributive shock look different
MVO2 shock can be normal
