Ch13: Shock Flashcards
what is shock
inadequate cellular perfusion
perfusion
the circulation of blood to tissues to meet the cells’ needs and remove waste
perfusion triangle
heart
vessels
blood
how does the body compensate for hypoperfusion?
it redirects blood flow from organs that can withstand more time without oxygen such as skin and intestines
how to calculate pulse pressure
systolic – diastolic pressure
what does a wide pulse pressure tell us?
the heart is working harder, arteries have become less flexible or both. very high pulse pressures may indicate heart disease
what are sphincters in the capillary bed controlled by?
autonomic nervous system
factors affecting adequate perfusion
1) adequate blood flow
2) adequate gas exchange and oxygenation of the blood
3) adequate glucose level
4) adequate removal of waste
(think ab aerobic respiration)
which part of the nervous system controls the flight or flight response?
sympathetic (part of autonomic peripheral NS)
3 causes of shock (hint: perfusion triangle)
- pump failure - cardiogenic shock, and obstructive shock (like pulmonary embolism, cardiac tamponade, tension pneumothorax)
- poor vessel function + excessive vasodilation - distributive shock like sepsis, anaphylactic shock, neurogenic shock, psychogenic shock)
- low fluid volume - hypovolemic shock (including hemorrhagic and non-hemorrhagic shock)
4 types of shock
cardiogenic
obstructive
distributive (sepsis, anaphylactic, neurogenic, psychogenic)
hypovolemic (hemorrhagic and non-hemorrhagic)
how does cardiogenic shock –> pulmonary edema
cardiogenic shock damages heart muscle so it does not pump as well. because of the less efficient pumping, blood is backed into the pulmonary vessels. this pressure pushes fluid into the alveoli, causing pulmonary edema and inefficient oxygenation (tachypnea, crackles, rales).
*note: edema = excessive fluid build up
myocardial contractibility
ability of the heart to contract
preload
the pressure increase as blood fills the heart during diastole
blood enter the heart in diastole –> stretch walls + preload –> ? myocardial contractibility
increases myocardial contractibility
afterload
the pressure/force of the heart when pumping out the blood (systole)
consequences of increased afterload
heart overworks –> heart failure in the long term (similar to the idea of wide pulse pressure)
factors that lead to cardiogenic shock
low cardiac output (stroke volume x HR)
high preload
low preload
poor myocardial contractility
pericardial effusion
fluid going into pericardial sac
pericardial tamponade / cardial tamponad
excessive build up of fluid in pericardial sac, preventing blood from filling up ventricles
signs and symptoms of cardiac tamponade
BECK TRIAD
1) jugular vein distention
2) muffled heart soudns
3) narrowing pulse pressure (why? because heart cannot pump properly in systole and and there is A LOT of preload pressure during diastole because of resistance from fluid in pericardial sac when blood tries to flow into the ventricles)
pulmonary embolism
fluid bulid up
signs of neurogenic shock
no sweat below injury site
hypothermia
hypotension
skin pink, warm and normal
signs of anaphylactic shock
skin:
- flushed, itchy or burning sensation on face and upper part of face
- pallor
- cyanosis
- hives
- edema on face, lips
circulatory system:
- vasodilation
- drop in BP
- BP barely palpable
respiratory system:
- stridor
- itching or sneezing in nasal passages
- tightness in chest with dry cough
- dyspnea
- bronchi constriction
- secretion of mucus into lower airway
- cessation of breathing
other:
- abdominal cramping
- nausea
- vomiting
- altered mental status
- dizziness
- fainting and coma
Compensated shock
early stages of shock where the body’s homeostasis is still able to compensate for changes
signs of compensated shock
anxiety
restlessness
feeling of impending doom
weak, thready pulse
clammy skin
pallor
cyanosis at lips
shallow, rapid breathing
nausea or vomiting
CRT > 2 seconds
marked thirst
narrowing pulse pressure
signs of decompensated shock
BP falling
declining mental status
labored, irregular breathing
ashen, cyanotic skin
thready or absent peripheral pulse
dull eyes, dilated pupils
poor urinary output
how to deal with a patient with suspected shock
1) primary assesment
2) history taking - more abt chief complaint
3) secondary assessment
4) reassessment
*same as patient assessment without scene size-up
primary assessment of patient with suspected shock
- scan for bleeding
- assess LOC
- airway
- breathing
- circulation - both distal & central pulses, mental status, CRT
what to look for in history taking
SAMPLE
signs & symptoms (chief complaint)
allergies
meds
past med history (e.g. anticoagulants?)
last oral intake
events leading up to injury
what is secondary assessment for
uncover injuries that were not found in primary assessment
general emergency medical care for shock patients
- check for bleeding; manage by applying pressure and tourniquet if needed
- ABCs
- spinal motion restriction if there is possibility of spinal injury
- if there is enough time, splint any fractures or broken bones
- consider calling ALS backup
- reassessment every 5 mins for unstable patients
potential causes of cardiogenic shock
inadequate heart function
something abnormal with electrical impulses
disease of muscle tissue
disease/injury
signs and symptoms of cardiogenic shock
chest pain
cyanosis
cool clammy skin
weak pulse
BP low
pulmonary edema
anxiety
crackles
how to treat cardiogenic shock
administer high-flow oxygen (e.g. NR mask)
assist ventilations if needed
position comfortably
consider ALS
causes of obstructive shock
obstruction of cardiac muscle leading to decreased CO:
pulmonary embolism
pericardial tamponade
tension pneumothorax
how to treat obstructive shock
administer oxygen
ALS assist, rapid transport
for pericardial tamponade: the only thing can be done is provide oxygen to prevent hypoxia. blood needs to be drained from pericardial sac but that is an ALS skill so CONSIDER ALS ASSIST
symptoms of obstructive shock
dyspnea
cyanosis
rapid, weak pulse
rapid, shallow respirations
decreased lung compliance
jugular vein distention
cyanosis
Beck triad (cardial tamponade): muffled heart sounds, narrowing pulse pressure, JVD
cause of septic shock
severe infection
symptoms of sepsis
fever
tachycardia
low BP
how to treat septic shock
it is a complex condition to take care of because it needs antibiotics so what an EMT can do is ADMINISTER OXYGEN!!
assist ventilations
keep patient warm
consider ALS
what causes neurogenic shock
damaged cervical spine that causes excessive vasodilation
symptoms of neurogenic shock
bradycardia
low BP
no sweating below site of injury
signs of neck injury
how to treat neurogenic shock
secure airway
administer oxygen
consider ALS
preserve body heat
rapid transport
*the most important thing is maintaining good blood flow bc neurogenic shock patients usually have enough blood but extreme vasodilation
what is anaphylactic shock
shock caused by life-threatening allergic reaction
symptoms of anaphylactic shock
burning, itching skin
constriction of airways
vascular dilation
edema
coma
rapid death
how to treat anaphylactic shock
administer oxygen
identify cause
assist with epinephrine injection
consider ALS
what is psychogenic shock?
lack of blood flow to brain causing syncope/fainting
treatment for psychogenic shock
determine duration of unconsciousness
patient supine position
record vital signs and initial mental status
transport promptly
assess and observe for any sign of head injury
symptoms of psychogenic shock
normal or low BP
rapid pulse
what causes hypovolemic shock
loss of blood volume = 1) fluid in blood or 2) the whole blood
signs of hypovolemic shock
low BP
rapid, weak pulse
increased RR
change in mental status
cyanosis
cool, clammy skin
treatment for hypovolemic shock
control external bleeding
secure airway
assist with breathing
administer oyxgen
rapid transport
consider ALS
nitroglycerin is usually administered for chest pain because it dilates the arteries. should it be given for cardiogenic shock?
NO. blood pressure is already low, nitroglycerin will exacerbate it
