Overview of Concepts
Shock is a SYNDROME resulting from a decrease in
a. ____________, that causes inadequate
b. __________ resulting in ischemic organs/tissues that cannot carry out cellular metabolism.
a. blood flow
b. oxygenation
Which of the following are assessment findings consistent with the compensatory stage of shock?
a. third spacing edema
b. weak pulses (1+)
c. tachypnea/acidosis
d. tachycardia with normal blood pressure
e. hypoglycemia
f. urine output decreasing; however, above 30mL/hr.
g. absent bowel sounds
h. capillary refill prolonged (>3 seconds)
b. weak pulses (1+)
d. tachycardia with normal blood pressure
f. urine output decreasing; however, above 30mL/hr.
h. capillary refill prolonged (>3 seconds)
**there is poor turgor in the compensatory stage, not third spacing edema (occurs in the progressive stage)
***while there is tachypnea, the patient is often alkalotic in the compensatory stage, acidosis occurs in the progressive stage due to anaerobic metabolism.
****hyperglycemia in the compensatory stage, not hypoglycemia (which occurs late stage shock)
*****bowel sounds are hypoactive, not absent which occurs later stages.
Why is serum lactate or lactic acid monitored for patients experiencing shock?
Lactic acid is the byproduct of anaerobic metabolism; therefore, elevated levels indicate profound cellular ischemia. It is an indicator of the severity of shock state.
A patient experiencing hypovolemic shock due to hemorrhage receives multiple transfusions of PRBCs in addition to FFP and Platelets. The HCT is now 35% and HGB is 12.8. What complication would be important to monitor for in a patient who has received multiple transfusions?
Hypocalcemia
Hypocalcemia as a result of transfusions occur due to the citrate anticoagulant contained in stored blood. The transfused citrate binds ionized calcium in the recipient, and the resultant hypocalcemia is thought to be most prominent after the transfusion of plasma and platelets, due to their high citrate concentration
When monitoring for effectiveness of treatment, which value is often used to titrate medications such as norepinephrine, as it is an indicator of tissue perfusion.
MAP >65 mmHg
These four (4) factors are necessary to maintain cellular metabolism and oxygen deliver. When one of these is disrupted, shock occurs.
1. Cardiac Output 2. Blood vessel diameter and tone 3. Blood volume 4. Tissues ability to extract and use O2.
What change is expected to LOC during the compensatory stage?
Confusion/restlessness or lightheadedness.
During the progressive stage the patient becomes more stuporous (deep state of unresponsiveness needing vigorous stimulation for any arousal/response, which occurs only briefly) and this progresses to a coma during the refractory stage.
How is base excess meaningful when evaluating a patient experiencing shock?
Base excess estimates the extent of acidosis at the tissue level. It is a measure of the severity of metabolic acidosis.
Which of the following would help to pull fluid into the intravascular space, increasing volume with less fluid resuscitation required (select all that apply)?
a. LR or 0.9% Sodium Chloride
b. Hespan 6%
c. 5% Albumin
d. 0.45% Sodium Chloride
e. 7.5% Sodium Chloride
b, c, and e are all hypertonic solutions. These will redistribute fluid into the vascular space, resulting in a reduced amount of fluid resuscitation being required.
a. LR or NS are isotonic, so fluid in and out would be nearly the same
d. 0.45% sodium chloride is a hypotonic solution which would result in fluid leaving the vascular space and redistributing into the extracellular/intracellular space.
If a vasoconstrictor type medication such as dopamine infiltrates in a peripheral site, which medication should be used as an antidote and how would it be administered?
Phentolamine diluted with 10 mL of NS, SQ injected directly into the infiltration. This will improve circulation in the area of the extravasation and thus decrease ischemia and cell death in the surrounding tissue.
Examples of Vasoconstrictor Medications: Dobutamine, Dopamine, Epinephrine, Metaraminol, Norepinephrine, Vasopressin, and Phenylephrine.
Administration: 5mg in 10mL of 0.9% sodium chloride Inject 1ml of the antidote SQ liberally to the infiltrated area within 12 hours of extravasation. DO NOT exceed 0.1- 0.2mg/kg or 5mg total. If dose is effective, normal skin color should return to the blanched area within 1 hour
Drawing a mixed venous O2 saturation (SVO2) from a PA catheter, is an invasive way to meticulously monitor what?
Oxygen consumption at the tissue level.
60-75% of the blood that returns to the heart should be oxygenated. Less than 60% indicates increased oxyen extraction at the tissue level indicating cardiac output is not high enough to meet the oxygen demands and needs of tissues.
Which findings indicate progression from the compensatory stage to the progressive stage?
Select all that apply:
1. Profound oliguria/anuria 2. increased lactic acid/ hyperkalemia 3. fluid shift from the interstitial space INTO the capillaries 4. Tachycardia with normal blood pressure
1. Profound oliguria/anuria 2. increased lactic acid/ hyperkalemia
What test might be used to diagnose septic shock (as opposed to cardiogenic shock)? 1. lactic acid level 2. BNP 3. blood cultures 4. EKG
Blood cultures.
How would blood cultures be used to diagnose? Determines the type of bacteria in the bloodstream and can assist with identifying the appropriate treatment.
When assessing a patient with cardiogenic shock what findings separate it from other types of shock?
Signs of L and R sided heart failure as well as myocardial ischemia.
Which type of shock would likely require short acting beta adrenergic medications in addition to antihistamines and epinephrine?
Anaphylactic
Short Acting Beta Adrenergic Medications include inhaled bronchodilators. Stimulates Beta-2 agonist receptors which cause smooth muscle relaxation in the airways.
When attempting to improve tissue perfusion, many interventions are aimed to increase cardiac output by either improving heart rate or stroke volume. What are the determinants of stroke volume and how would each affect stroke volume?
1. Preload (how much volume returns to heart) - Increasing preload, increases stroke volume (SV).
2. Contractility - (how effectively the myocardium squeezes) - increasing contractility, increases SV.
3. Afterload - (the amount of pressure L ventricle must overcome) - DECREASING afterload, INCREASES stroke volume.
A patient is involved in a MVC. Which finding would indicate neurogenic shock as opposed to hypovolemic shock?
1. Decreased hgb and hct
2. Bradycardia
3. Tachycardia
4. Hypotension
5. Hypertension
Bradycardia
Manifestations initially are related to “rest and digest” response - Hypotension, bradycardia, bradypnea, flushed skin (secondary to vasodilation).
CBC with differential is obtained and an eosinophil count is important for which specific type of shock?
Anaphylactic. Eosinophils are elevated with allergic reactions.
When assessing a patient with obstructive shock what findings separate it from other types of shock?
Very often a result of cardiac tamponade (muffled heart tones) requires a pericardiocentesis
Tension pneumothorax (asymmetric chest rise, deviated trachea) requires a thoracentesis.
While hypotension is often profound requiring the use of vasoconstrictor type critical care drip medications, this type of shock may also require vasodilator drip medication in order to decrease SVR and increase perfusion of the coronary arteries.
Cardiogenic shock.
Inotropic/vasoconstrictor medications increase cardiac output and contractility of the heart muscle, and vasodilators such as nitroglycerin may be added to decrease preload and afterload through arterial dilation.
When reviewing hemodynamic monitoring, what do each of the following values reflect?
a. Central Venous Pressure (CVP)
b. Mixed Venous Oxygen Saturation (SVO2)
c. Systemic Vascular Resistance (SVR)
d. Cardiac Output (CO)
a. CVP = R heart preload/R Vent. Filling Pressures
b. SVO2 = Oxygen consumption at tissue level.
c. SVR = Resistance the ventricles overcome to eject blood into circulation.
d. CO = Amount of blood heart pumps per minute
Poor turgor is common during the compensatory stage due to blood shifting into the capillaries to increase volume. As shock progresses, what causes the third spacing edema during the progressive stage?
Failure of the sodium/potassium pump causes cell rupture and ultimately shifts fluid back into the interstitial spaces.
Troponin and CPK (cardiac enzymes) laboratory levels would be monitored for which type of shock?
Cardiogenic
How does the assessment of the skin with distributive types of shock vary from hypovolemic, cardiogenic and obstructive types?
Vascular pooling causes skin to be warm/flushed with neurogenic and early septic shock. Anaphylactic shock often manifests with hives and itching also.
Which type of shock would likely require IV vancomycin?
Septic shock
What are two important assessment data available via arterial line monitoring?
1. Continuous (arterial) blood pressure measurements
2. Easy access for ABG samples
**Never use the line for infusing fluids or meds and protect it as there is an increased risk of bleeding if dislodged!!**
What is the most severe respiratory complication that may result due to shock?
ARDS (acute respiratory distress syndrome)
Septic Shock: MODS, Complication as a result of excessive inflammation associated with severe sepsis. Typically begins in the lungs with the development of ARDS.
What kind of data would the CMP (complete metabolic panel) contain that the BMP (basic metabolic panel) would not, and why would this be important for patients experiencing shock?
In addition to the electrolytes and kidney function values of the BMP, the CMP also reflects protein, albumin and liver enzyme counts. This can be important to detect organ failure.
Which type of shock may require atropine or pacemaker due to profound bradycardia?
Neurogenic
Beta-1 adrenergic receptors are found in this location and have this response when stimulated.
Found in the heart and kidneys and increase myocardial contractility and heart rate.