Shock Syndromes Flashcards
Shock
What is the definition of shock?
- persistent hypotension (<90/70 mmHg) or acute decrease in SBP of 40 mmHg or more
- unresponsive to initial therapy
- clinical signs of end-organ dysfunction (hypoperfusion)
Shock
What are the signs of end-organ dysfunction?
- heart = tachycardia, hypotension
- brain= altered mental status
- kidneys= decreased urine output
- liver= increased INR or bilirubin
- skin= cool, cyanotic
Shock
What are the types of shock?
- hypovolemic
- distributive
- cardiogenic
- obstructive
Shock
What are the hemodynamic interactions of hypovolemic shock?
- primary problem: decreased preload
- other resulting problems: decreased stroke volume (SV), cardiac output (CO) and mean arterial pressure (MAP)
- compensation: heart rate (HR) and systemic vascular resistance (SVR)
Shock
What are the reasons for the volume depletion?
- acute hemorrhage/trauma
- GI disorders (vomiting, diarrhea, ascites)
- thermal injury
- enviromental exposures
- renal salt wasting
- third spacing
- septic shock
Shock
What are the signs/symptoms of hypovolemia?
- altered mental status, restlessness, agitation, obtundation
- decreased turgor, cool and clammy skin
- ashen, gray skin or pale extremeties
- rapid, thready, irregular pulse or not palpable
- dry mucus membranes
- delayed capillary refill
- hypotension
- decreased urine output, acute renal failure
Shock
What fluids are preferred for resuscitation?
1 L IV crystalloid, isotonic solutions such as LR (warmed and given as quickly as possible)
Shock
What are the goal endpoints for resuscitation?
- normalization of vital signs (BP, HR)
- clearing of sensorium
- good peripheral perfusion (warm fingers/toes, normal capillary refill)
- UOP > 0.5 mL/kg/hr
- resolution of metabolic acidosis, normalization of base deficit
- normal serum lactate
Shock
What is given to patients who are unresponsive to crystalloids with hypovolemic shock?
blood
cannot give in same line as LR
Shock
What is the goal central venous pressure (CVP) after resuscitation?
8-12 mmHg
Shock
What is the goal mean arterial pressure (MAP) after resuscitation?
65 mmHg +
Shock
What is the goal urine output (UOP) after fluid resuscitation?
UOP > 0.5 mL/kg/hr
Shock
What fluids are crystalloids?
- NS or 1/2 NS
- D5W
- LR
- normosol/plasma-lyte
Shock
What fluids are colloids?
- albumin
- hetastarch
- tetrastarch
- blood
Shock
Which crystalloids are considered balanced salt solutions?
- lactated ringers
- normosol-R
- plasma-lyte
Shock
What is the risk of using NS over a balanced salt solution (BSS)?
- increased mortality
- increased hyperchloremic metabolic acidosis
- increased blood transfusions
- increased renal injury
- increased hyperkalemia
- increased postoperative infection
Shock
When may it be appropiate to use NS for resuscitation?
traumatic brain injury/neurosurgical patients due to increased need for Na+
Shock
What is the use of colloids?
contain large solutes to exert oncotic pressure
Shock
What are the common indications of albumin?
- volume expansion
- shock
- burn
- acute respiratory distress syndrome (ARDS)
- intraoperative fluid repletion
Shock
What are the adverse effects of albumin?
- hypervolemia
- azotemia
- infusion-related reactions/anaphylaxis
Shock
When should synthetic colloids not be used?
severe sepsis
Shock
What is the black box warning associated with hydroxyethylstarch (HES), synthetic colloids?
associated with mortality and renal injury requiring renal replacement therapy in critically-ill patients, including patients with sepsis; avoid use in critically ill adult patients, including those with sepsis
Shock
What is the place in therapy for blood replacement?
- acute blood loss
- inadequate resusitation from fluids alone
- preoperatively
- low hemoglobin
Shock
How much does hemoglobin increase with 1 unit of packed red blood cells (PRBCs)?
1 g/dL
Shock
How is fluid status monitored?
- daily weight
- daily I/O
- volume status
- urine output (> 0.5 mL/kg/hr)
- vitals
- pulmonary edema
- abdominal compartment syndrome (bladder pressure)
- base deficit
- serum lactate
Shock
What additional fluid losses need to be taken into account that may not be easily measurable?
- burns
- NG output
- vomiting
- diarrhea
- fistulas
- drains
- bleeding
- large wounds
Shock
What are the hemodynamic interactions of septic shock?
- primary problem: decreased systemic vascular resistance (SVR)
- other problems: decreased preload, decreased mean arterial pressure (MAP)
- compensation: increased heart rate (HR) and increased cardiac output (CO)
Shock
What is septic shock?
sepsis (increase in SOFA score 2+ from basline) associated with circulatory, cellular, and/or metabolic dysfunction. vassopressor required to maintain MAP 65mmHg+ and serum lactate < 2
high mortality!
Shock
When should antibiotics be initiated for septic shock?
within 1 hour of recognition
Shock
When should resuscitation fluids be administered for septic shock?
within 3 hours
Shock
What is the first line fluid for resuscitation in septic shock?
crystalloid, balanced salt solutions > NS
Shock
When would albumin be utilized in septic shock?
used in addition if patients require large volumes of crystalloids
Shock
What is the first line vasoactive medication for septic shock?
norepinephrine
Shock
When may a second vasoactive medication be added to therapy for septic shock?
if MAP remains inadequate
Shock
Where are pressors administered?
central venous access, but short term peripheral is tolerated (risk of extravasation, local tissue ischemia, and injury)
Shock
What is the dosing of norepinephrine?
0.01-3 mcg/kg/min (usually 0.25-0.5) IV infusion, titrate to MAP goal, DO NOT BOLUS
Shock
What are the effects of norepinephrine?
- increases systemic vascular resistance (SVR)
- reduce techycardia
- decrease renal perfusion (ensure adequate fluid resuscitation)
- peripheral ishemia (consider fluid status)
Shock
What are the monitoring parameters for norepinephrine therapy?
extravasation and skin necrosis
Shock
What is the dosing of vasopressin?
0.03 units/min IV infusion, DO NOT TITRATE, DO NOT BOLUS
Shock
What are the effects of vasopressin?
peripheral vasoconstriction, higher doses are associated with coronary vasoconstriction, peripheral ischemia/necrosis, coronary or bowel ischemia
Shock
What is the dosing of epinephrine?
0.01-0.05 mcg/kg/min IV infusion, titrate to MAP goal, DO NOT BOLUS
Shock
What are the adverse effects of epinephrine?
- tachyarrhythmias
- increased blood glucose
- increased lactate (risk of lactic acidosis)
- monitor for extravasation and skin necrosis
Shock
What are the effects of dopamine?
dose-dependent receptor specific effects
- low doses = dialates mesenteric, renal, and cerebral vascular beds
- intermediate doses= beta-1 adrenergic (elevation in cardiac output and mean arterial pressure)
- high doses= alpha-1 adrenergic and NE release (increased systemic vascular resistance (SVR)) more SE
may also cause tachyarrythmias
Shock
What is the dosing of dopamine?
titrate to MAP goal, DO NOT BOLUS
Shock
What is the use of phenylephrine?
never used alone, and never firstline due to minimal cardiac activity
Shock
What is the dosing of angiotensin II?
20ng/kg/min to max of 80ng/kg/min in first 3 hours, MD max of 40 ng/kg/min
limited to no data for shock
Shock
What is the role of corticosteroids in shock?
septic shock with ongoing requirements for vasopressors, not for patients with sepsis alone
Shock
What is the role of sodium bicarbonate in shock?
septic shock + severe metabolic acidosis ( pH < 7.2) + AKI (AKIN score 2-3)
