Shock Flashcards
shock
= arterial blood flow inadequate to meet tissue needs for O2
- tissue perfusion depends on CO and SVR
- CO depends on preload, contractility, and afterload
- SVR depends on viscosity, vessel length and diameter (SVR=vL/r4)
hypovolemic shock
decreased CO and PCWP (CVP < 5 mmHg) with increased SVR.
- . Hemorrhage induced
- Fluid loss induced
- Poor intake
: blood vessels are empty, will have deceased CO, decreased central venous pressure because there isn’t volume, have decreased pulmonary capillary wedge pressure b/c there is no volume, have increased systemic vascular resistance (b/c blood vessels are clamped, trying to maintain CO)
cardiogenic shock
decreased CO (< 2.2 l/min/m2) with increased PCWP and SVR.
- Cardiomyopathies
- Arrhythmias
- Mechanical
4.Extracardiac/Obstruction
(tension pneumothorax, PE, cardiac tamponade)
: heart isn’t putting out blood, the CO will be decreased (aka cardiac index is low, this is CO divided by weight), preload and afterload are both increased b/c they are just sitting there, and not being pumped out. the increased PCWP and SVR.
obstructive shock
could be considered a type of cardiogenic - due to decreased blood flow
ex. tension pneumo, PE, cardiac temopnade
pulmonary capillary wedge pressure
is measured in left side of heart- it is in the left atria
central venous pressure
measured in right side of heart
distributive shock
“vasodilatory - warm shock”
- increased CO (> 4.0 L/min/m2)
- decreased SVR (< 800 dynes.S/cm-5) and decreased PCWP (can be normal)
- seen in sepsis, toxic shock syndrome, anaphylaxis, toxin reactions (heavy metal, insect bites, etc.), spinal cord injury (neurogenic), myxedema, or adrenal crisis.
- May also have normal (70%) to high central venous O2 saturation (CVOS) due to redistribution of flow.
has to do with blood distribution: all the blood is going to skin, no blood going to the vital organs – it is a distribution problem – it is all going to skin b/c afterload is reduced, vessels are all dilated and the skin and muscles is where all the blood goes. CO increases b/c there is no afterload – as it pumps it just blows it out t
what are clinical markers of shock?
- SBP < 90 mm Hg (or mean BP < 60-65 mm Hg)
- three “windows” of body:
- cutaneous - see mottled/blotchy extremities
- renal: 1.0 mmol/L
A 56 year old alcoholic patient with cirrhosis and ascites presents with vomiting, dry mucous membranes, clammy skin, oliguria, mental status change and BP of 70/50. This patient has which type of shock?
this patients fluid is all in abdomen, this patient is dehydrated = hypovolemic shock due to protein leaving blood (liver not making albumin) – all fluid is out in tissue
- Will see decreased CVP (central venous pressure)
normal CVP?
0-5 mm Hg
normal CO?
2-4 L/min/m2
normal PCWP?
8-12 mmHg
normal SVR?
800-1500 dyne-sec-cm-5
tx of hypovolemic shock?
CVP<5 mm Hg
- 0.9% saline – 1-2 liters wide open – continue based on BP, skin, urine and mentation
- PRBCs (packed red blood cells)
Goal to obtain CVP 8-12 mmHg
52 y/o female diabetic presents with dyspnea and BP of 65/50. History is positive for an old MI. The patient is on a loop diuretic, an aldosterone antagonist, an ACE inhibitor, and a beta blocker. Heart rate is 140. The skin is cool and clammy and the patient is restless. There are bilateral basilar crackles and the neck veins are distended. This patient most likely has which type of shock?
cardiogenic shock
CO is low, PCWP is high, afterload is high because the problem is the heart
tx or cardiogenic shock? first step…..
Upright, O2, NIPPV
tx or cardiogenic shock? for low BP?
Dobutamine (or milrinone w/ intraaortic balloon couterpulsation)
dobutamine: is mostly inotropic, If its cardiogenic shock not due to MI Then use dobutamine
tx or cardiogenic shock? for normal/high BP
IV nitroglycerine/nitroprusside with IV loop diuretic (furesomide)
tx or cardiogenic shock? for A fib….
esmolol
tx or cardiogenic shock? Post MI…
antiplatelets, norepinephrine* or dopamine** if hypotensive (dobutamine or milrinone# for those with vasoconstriction and not as severe hypotension)
- always use NE if its related with MI
- NE and dopamine are vasopressors
A 46 y/o female with lung cancer presents with dyspnea and cough. Heart sounds are distant and lungs are clear. Neck veins are distended. BP is 60/40. EKG shows QRS complexes that alternate in size….
patient has pericardial tamponade
small complex is called electrical alterans – the heart is swinging back and forth, its swinging out toward EKG and swings back because its in a bag of water – can’t get enough blood into heart to have effective blood pressure, this explains low blood pressure, the distended neck vv. is due to high preload, there is distension
Beck’s Triad for cardiac tamponade?
Distended neck veins
Distant heart sounds
Distressed BP (Hypotension)
cardiac tamponade
acute type of pericardial effusion in which fluid accumulates in percardium causing restriction of heart contraction - may be due to trauma, pericarditis, myocardial rupture, uremia, hypothyroidism.
TEE shows an echo free space anterior and posterior to the left ventricular wall. This represents which type of shock?
obstructive shock - there is a bag of water surrounding the heart - see Beck’s triad
causes of obstructive shock?
Tension pneumothorax Pericardial disease Disease of pulmonary circulation (PE) Cardiac tumor (myxoma) Left atrial mural thrombus Obstructive valvular disease
A 25 y/o HIV patient presents with cough, fever of 390C and heart rate of 98 beat/min. Respiratory rate is 26 breaths/min with WBC of 9,000 cells/mm3 with 15% bands. Glucose is 145 mg/dL. This patient most likely has:
patient has SIRS
SIRS
systemic inflammatory repsonse syndrome
- due to cytokine storm –> leads to sepsis –> leads to shock
Classification:
- body temp greater than 100.4 or less than 96.8
- heart rate greater than 90 bpm
- tachypnea (high resp. rate) gretaaer than 20 bpm
- leukocytes less than 4,000 or greater than 12,000; or presence of 10% immature neutrophils (band forms), bandemia or left shift
what is usual acid base imbalance during SIRS?
if have increased RR, then see respiratory alkalosis
What labs to order with SIRS pt?
CBC CMP- chemical profile ABGs Type and crossmatch Coagulation parameters Lactate Blood cultures
A gram stain sputum is obtained on the above patient and shows clusters of a gram positive cocci. One may now diagnose:
sepsis
PAMPs vs DAMPs
result in sepsis:
due to Pathogen-Associated Molecular Patterns (PAMPs), ie. glycolipids, glycoproteins, lipoproteins, peptidoglycans, lipopolysaccharides, mannoproteins, DNA, RNA, etc. which activate Pattern Recognition Receptors to release cytokines and chemokines and thus produce SIRS/Sepsis.
DAMPs = damage-associated molecular patterns, released due to pancreatitis, burns, auto accidents etc.
cytokines related to septic shock/
IL1, IL6, IL8, TNFalpha, IFGNgamma
What is sepsis?
infection +….
TPR changes –T > 38.3C or < 36C; HR > 90 bpm; RR > 20bpm
Glucose > 140 mg/dL
Altered mentation
Edema of > 20mL/kg over 24 hours
inflamm/ hemodynamic variables indicative of sepsis?
inflammatory variables:
- **WBC > 12,000 with bandemia > 10%
- ** WBC < 4,000
- increased CRP and procalcitonin
Hemodynamic variables: worsen with worsening sepsis!
SBP* < 90 mmHg; MAP < 70 mmHg
organ dysfunction variables seen in sepsis?
PaO2/FiO2 < 300 ( 0.5 *mg/dL (> 2 mg/dL)
INR > 1.5 or PTT > 60 seconds
Ileus – intestines are going
Platelets < 100,000 microl-1 – HGB is going
Bilirubin > 4 mg/dL – liver dysfunction
Hyperprolactinemia > 1 mmol/L (tissue hypoxia)
Decreased capillary refill (tissue hypoxia)
- these worsen with development of severe sepsis
how many factors needed to ddx severe sepsis?
1 (or more) organ dysfunction
The above patient is considered to have developed septic shock when unable to maintain a mean arterial pressure > 60 mmHg after:
fluid resuscitation
Distributive shock, including septic shock, anaphylaxis, or adrenal insufficiency is characterized by:
SVR < 800 dynes.s/cm-5.
In septic shock a redistribution of oxygen delivery or inability of tissues
to extract O2 can actually lead to a high central oxygen saturation of
greater than 70%, in the presence of increased serum lactate. Ultimately, however, the CVOS may drop and require fluid, RBCs, and vasopressors to maintain it above 70%.
early sepsis protocol
to be done within 2 hours of pt. with infection:
Serum lactate Two sets of blood cultures Two 18 gauge lines Start antibiotics Give 2 liters NS CBC and BMP O2 sat > 90% Start norepinephrine if shock is present. Transfer for lactate > 4 mmol/L, Systolic BP < 90 mm Hg, or MAP < 60 after 2 liters of NS.
Therapy of septic shok?
- maintenance of CVP at 8-12 mm: give 5 L fluid initially
- need to maintain MAP at >65 mm Hg, and CI at 2-4 l/min: give vasopressors
- use NE
- Phenylephrine for warm shock
- Epi for anaphylactic shock - maintain central venous O2 sat >70% by giving PRBC and dobutamine
- hope to reduce lactate levels by 20% in first 2 hours
maintain MAP at what?
need to maintain MAP at >65 mm Hg, and CI at 2-4 l/min: give vasopressors
- use NE
- Phenylephrine for warm shock
- Epi for anaphylactic shock
maintain CVP?
. Need to maintain CVP at 8-12 mm Hg. Fluids 5 liters in initial 6 hrs.
how do you maintain central venous O2 saturation with sepsis?
to maintain central venous O2 saturation at > 70%. For < 70% give PRBC* to obtain hemacrit of 30%. If still < 70%, then dobutamine as ionotropic therapy
why give steroids with septick shock?
Cortisol response of 9 ug/dL or less after 250 mcg of ACTH = relative adrenal insufficiency – use hydrocortisone 50 mg q 6 hrs.
