shock Flashcards
essentials of shock dx
Hypotension
Tachycardia—often first symptom
Oliguria (dec. urine output)
AMS-very common
Peripheral hypoperfusion and impaired O2 delivery : why tx is set up: to inc. perfusion
*shock is important because regulated tightly by CMS (compensated-need to meet medicare guidelines) prevent ppl from dying of shock
Flow chart for the basics of shock
Arterial blood flow can not keep up demand of tissues metabolic needs
- ->resulting in hypoxia to the body as a whole
- ->Resulting in anaerobic metabolism to kick in at peripheral tissues (bad!)
- ->Resulting in lactic acidosis (lab test: lactate) do not want!! (TEST: prognostic indicator of “badness”)
shock: AMS Marshall stat
60-70% nursing home pts w. AMS have UTI, may not have fever, but hypothermia: poor px
types of shock
Hypovolemic
Cardiogenic
Obstructive
Distributive
hypovolemic shock
Decreased intravascular volume-Due to loss of blood, fluid, electrolytes (Clinical setting tells all here usually)
-Blood loss from whatever reason (trauma, ruptured ectopic pregnancy, GI bleed, etc)
-Loss of fluid and electrolytes (N/V/D)
-Body will compensate by vasoconstricting, but after 15% loss of volume, shock sets in : Oliguria, AMS, cool extremities, diaphoresis, pale
Narrow pulse pressure (reduced SV, clinically relevant)
Decreased PCWP, CO, venous return; Elevated TPR (low cardiac output failure)
-Improves with fluids
Cardiogenic shock
Results from cardiac failure (MI, CHF)
Heart cannot maintain necessary CO
Defined as evidence of tissue hypoxia due to decreased CO in the presence of adequate intravascular volume.
-due to: MI, cardiomyopathy, valve dysfunction, arrhythmias (unstable VT, SVT (fine in younger pts, not in 70+)
-presentation: Oliguria, mental status changes, diaphoresis, cool extremities, jugular venous pressure is elevated, pulmonary edema might be present with respiratory failure, Low output failure (elev TPR, Low CO, venous return), Elev PCWP, BP improves with fluids
How to differ between cardiogenic and hypovolemic shock
test question
Cardiac ECHO (and history, duh!!)
Hypovolemic shock: LV will be small due to poor filling, but maintains contractility
(doing what it should, not enough fluid to pump)
Cardiogenic shock: decrease in LV contractility
(problem with heart)
Obstructive shock
Cardiac tamponade
Tension pneumothorax (needle first remember, not chest tube)
Massive PE
Distributive shock (septic, SIRS, neurogenic, anaphylaxis) (CMS worries about THIS one)
Also known as vasodilatory shock
Produces a decreases in systemic vascular resistance…resulting tissue hypoperfusion (volume is there, just very vasodilated)
Normal circulatory volume
Low TPR, PCWP
Elevated CO, venous return (high output failure)
Vasodilation (warm dry skin) (not cold, pale, diaphoretic)
SIRS
Systemic Inflammatory Response Syndrome
Can occur from an infectious cause, or noninfectious (burns, pancreatitis, trauma, ischemia)
“baby sepsis”
SIRS: need to have at least 2 of the following:
- Temp more than 100.4, or less than 96.8
- HR more than 90
- RR more than 20 or hyperventilation with a CO2 on abg less than 32
- WBC more than 12 or less than 4 or greater than 10% bands
Septic shock
The new rage!!!!
SIRS + a source (UTI, pneumonia, cellultis, meningitis)
-Most common type of distributive, 20-50% mortality
-Risks are age, DM, immunosupression (AIDs, steroids), recent invasive procedures
-Most common due to gram negatives (E coli, Pseudomonas*, Klebsiella)
Shock in setting of DIC from trauma often is from sepsis
Neurogenic shock
Caused by traumatic spinal cord injury or by effects of an epidural, or spinal anesthetic
Loss of sympathetic tone and systemic vascular resistance
Hypotension WITHOUT a compensatory tachycardia
A benign other type of neurogenic shock which can result in syncope is “vasovagal syncope”—caused by pain, gastric dilatation, or fright, producing hypotension, bradycardia, and syncope. (may get better with laying down, in contrast to septic shock)
shock s/s
- Hypotension: may be masked in early stages by compensatory mechanisms such as tachycardia, increased cardiac contractility, and vasoconstriction
- Cool and mottled extremities
- Splanchnic vasoconstriction can lead to oliguria (lead to renal failure), bowel ischemia, hepatic dysfunction, MSOF, AMS is very very common
sepsis lab markers
lactate (draw serial lactates to monitor how well tx is working)
procalcitonin
General treatment measures
what type of acid/base imbalance??
ABC’s with prompt intervention
- Respiratory failure not uncommon—due to existing metabolic acidosis (can’t compensate with respiratory hyperventilation, still tachypnic)
- Intubation can reduce O2 demand of respiratory muscles and allow improved oxygen delivery to other hypoperfused tissues.
Monitor urinary output (bad if nothing coming out while giving fluids), possibly foley
IV fluids for hypotension
Hemorrhagic shock: Volume tx
IVF to an extent
BLOOD!: need the O2 carrying capacity vs. saline (just fluid volume, but body need O2 carrying capacity!!–>blood)
O neg (universal if no time)
Type and Cross if have time (30-45-60 min)
Hypovolemic shock volume tx
.9NS 1 L increments usually
Cardiogenic shock volume tx
.9NS 250ml boluses—be careful here not to fluid overload—pressers (inc. BP)
“baby boluses”, not giving Liters here (contractility issue), the heart is failing, will put in CHF–>use pressors
Septic shock (i.e. SIRS + source) volume tx
30ml/kg .9NS to start off
WITHOUT exception
100 kg guy: 3L! (tons of fluid, hard to do)
main enemy is hypotension, not necessarily HF
Early Goal Directed Therapy for septic shock
test question
.9NS to achieve CVP (central venous pressure) 8-12 mm Hg
Vasopressors to achieve MAP 65 mm Hg or greater
PRBCs (packed RBCs) to achieve Hgb of 10 or greater
Results in lower mortality and morbidity
When fluids don’t work to maintain blood pressure ??
PRESSORS!
Need central line to give (not IV, localized inc. in pressure–>necrosis (story: lost leg)
Dobutamine, Norepinephrine (Levophed), vasopressin, dopamine
DO NOT place central line in artery: how to tell in vv vs. aa: ABG should be a lot different (higher O2) than values measured in vein (problem if same!! implies you are in artery)
Corticosteriods used in shock when due to ??
adrenal insufficiency
Otherwise, not shown to be beneficial
abx for ??
Septic shock
SIRS
Vancomycin for MRSA in oldies
Narrow pulse pressure (reduced stroke volume)
Decreased PCWP
decreased CO
decreased venous return Elevated TPR
hypovolemic shock
low output failure
Normal circulatory volume Low TPR low PCWP Elevated CO elevated venous return
distributive shock (sepsis, SIRS, neurogenic, anaphylaxis) high output failure
Low output failure elevated TPR Low CO low venous return Elev PCWP
cardiogenic shock
low output failure
