Hemodynamics Part II: shock Flashcards
define shock
transition between illness and death
shock aka
cardiovascular collapse
clinical manifestations of the inability of the circulatory system to adequately supply tissues with nutrients and remove toxic waste
shock
inadequate blood flwo secondary to decreased CO or mal-distributed output that results in irreversible tissue damage
shock
sequela of shock
hypotension –> impaired tissue perfusion –> cellular hypoxia
three major classifications of shock
cardiogenic
hypovolemic
septic
neurogenic shock
neurogenic dysfunction causes loss of vascular tone and peripheral pooling of blood (severing above T6)
anaphlactic shock
genrealized IgE mediated hypersensitivity response associated with vasodilation and increased vascular permeability
etiological classificiation
SSHHOCCKE
septic spinal (neurogenic) hypovolemic hemorrhagic obstructive cardiogenic cellular toxins anaphylactic endocrine/adrenal crisis
common final pathway of shock
cellular injury
five unifying features of shock
intracelllular calcium overload
intracellular hydrogen ion
cellular and interstitial edema
catabolic metabolism
inflammation
rosen’s empiric criteria for the diagnosis of shock (need 4 out of 6)
- ill appearance of decreased LOC
- HR > 100
- RR> 22 or PCO2 < 32
- Base deficit < -5 or lactate > 4
- urine ouput < 0.5 ml/kg/hr
- hypotension > 20 min duration
can you be in shock without being hypotensive?
yes
what is the base deficit?
amount of base required to neutralize the pH (normal is > -2)
three stages of shock
nonprogressive stage
progressive stage
irreversible stage
reflex compensation
mechanisms maintain tissue perfusion
nonprogressive stage of shock
worsening circulatory/ metbolic imbalance
acidosis
progressive stage of shock
at what shock stage to arterioles dilate –> poolin gin microcirculation
microcirculation
define cardiogenic shock
decreased CO adn evidence of tissue hypoxia in presence of adequate intravascular volume
criteria for cardiogenic shock (4)
hypotension < 90 for 30 min
30 mmHg below baseline
cardiac index < 2.2. L/mi/m2
PCWP pulmonary capillary wedge pressure >15 mmHg
or 4/6 rosens
1500-2000 volume blood loss and patient is confused- what class of hemorrhagic shock ?
class III
what is the advantage of giving a colloid in hemorrhagic shock?
less fluid required
more volume in vascular space
potential to draw fluid in from tissues
what clinical characteristics define SIRS systemic inflammatory response syndrome
- Temp > 38 or < 36
- HR > 90
- RR >20 or PaCO2 12 or 10% bands
sepsis =
SIRS + documented infection
sever sepsis =
sepsis + multi-organ dysfunction
septic shock =
sepsis + hypotension refractory to volume resuscitation
neurogenic shock
loss of symphatetic autonomic function due to spinal cord injury
pathophysiology of neurogenic shock
hypotension (due to loss of sympathetic tone thus vasodilation and decreased SVR) and bradycardia (due to unopposed parasympathetic (vagal) tone to the heart)
lesion at or above T6
hypotension beacuse lower lesions leave enough of the body with intact sympathetics so that blood pressure doesnt drop
lesions at or above T4
bradycardia beacuse sympathetic innervation to heart is at T4
what type of hypersensitivity reactor is anaphylactic shock?
type 1 hypersensitivity rxn
IgE mast cells
