Critical Care

  1. What is a Swann-Gans catheter?
    a pulmonary artery catheter
  2. What is stroke volume (SV)?
    the volume of blood ejected during systole
  3. What is cardiac output?
    HR x SV (L/min)
  4. What is Cardiac Index?
    total blood flow from the heart (L/min) divided by BSA (Body Surface Area)
  5. What is Systemic Vascular Resistance (SVR)
    estimates the degree of peripheral vascular contraction/dilation (vascular tone)
  6. What is Pulmonary Capillary Wedge Pressure (PCWP)?
    measures the left ventricular end diastolic volume
  7. What is Central Venous Pressure (CVP)?
    • can be used to estimate fluid status of a patient, although affected by pulmonary vascular resistance changes
    • most commonly used to measure the LV preload
  8. What is Mean Arterial Pressure (MAP)
    • more reliable measure of perfusion of blood in the organs than blood pressure
    • calculated: [systolic BP + 2(diastolic BP)]/3
  9. What is the normal range and goal for MAP
    • 80-100 mmHg
    • goal: at least 65 mmHg
  10. What is ischemia?
    • organs need more O2 than they are getting
    • lactate levels are a good marker of O2 deficiency
    • keep liver fx in mind
    • once blood flow is returned to an organ, you will see a spike in lactate b/c it's being cleared now
  11. What is hemodynamic shock?
    • unsufficient circulating volume
    • Hypovolemic Shock
  12. What are the causes of hemodynamic shock?
    • dehydration
    • bleeding (gunshot would is most common cause)
    • diuretics
    • fluid shifts (3rd spacing: burns, cirrhosis, CHF)
  13. What are the effects of hemodynamic shock?
    • PCWP: down
    • SVRI: up or same
    • MAP: down
    • CVP: down
    • CI: down
  14. What is the treatment for hemodynamic shock?
    • fluids
    • crystalloids (usually first-line)
    • colloids (only if there is 3rd spacing occuring - to draw fluids into the vascular space)
  15. What crystalloids can be used to treat hemodynamic shock?
    • 0.9% saline
    • 3% saline
    • lactated ringers solution
  16. What colloids can be used to treat hemodynamic shock?
    • 5% albumin
    • 25% albumin
    • Hetastarch in 0.9% NS
    • blood
  17. What is cardiogenic shock?
    • ticker ticking poorly
    • may be combined with other types of shock
    • this is the only shock syndrome that you don't jump to adding fluids
  18. What are the effects of cardiogenic shock?
    • PCWP: up
    • SVRI: up
    • MAP: down
    • CVP: down or up
    • CI: down
  19. How do you treat cardiogenic shock?
    • dobutamine (B1 specific)
    • milrinone (potent inotrope, potent vasodilator - probably need a vasopressor, usually NE, to stop this from causing hypotension)
    • vasopressors (NE, phenylephrine - usually only with milrinone)
    • dopamine (not specific enough)
    • avoid fluids in most cases
  20. What is anaphylactic shock?
    often associated with peanuts and bee stings
  21. What are the effects of anaphylactic shock?
    • PCWP: up or same
    • SVRI: down
    • MAP: down
    • CVP: same
    • CI: up or same
  22. How do you treat anaphylactic shock?
    • epinephrine followed up by antihistamines and/or steroids
    • very acute and short-lived
  23. What is septic shock?
    • Sepsis + hypotension despite adequate fluid resuscitation(adding fluids)
    • release of cytokines (TNF-a, IL-1, IL-6) d/t damage to tissues or response to toxins
    • cytokines mediate inflammation and may activate coagulation (chemotaxis of leukocytes, vasodilation, capillary leak, activation of coag. cascade)
  24. What are the criteria for SIRS?
    • 3 of the following
    • hyper/hypothermia (>38 or <36)
    • tachycardia (HR > 90 bpm)
    • tachypnea (RR > 20 bpm or PaCO2 < 32 mmHg)
    • leukocytosis/leucopenia (WBC >12,000/mm3; <4,000/mm3 or >10% bands)
  25. What are the sequelae of SIRS?
    • may progress to shock
    • may progress to Acute Respiratory Distress Syndrome (ARDS)
    • may progress to Multiple Organ Dysfunction Syndrome (MODS)
  26. What is sepsis?
    infection + 2 SIRS criteria
  27. What is the definition of severe sepsis?
    • sepsis + organ dysfunction
    • hypotension
    • hypoxemia
    • acute lung injury (ALI)
    • PaO2/FiO2 <200 w/ pneumonia or <250 w/o pneumonia
    • Oliguria (UO < 0.5 mL/kg for > 2h
    • metabolic acidosis
    • platelets < 100,000/mm3
    • obtundation
  28. How do you treat septic shock?
    • antibiotics (will usually get worse initially d/t toxin release)
    • check CVP
    • check MAP
    • check Scv O2
  29. Norepinephrine
    • a and B agonist
    • 1st-line, especially in septic shock
    • by far, the most effective vasoconstrictor
    • dose-dependent increase in SVR
    • does not adversely effect CO
    • more potent than dopamine
    • can cause arrhythmias, but not as bad as other catecholamines
  30. dopamine
    • dose-dependent action of adrenergic and dopaminergic receptors
    • gets kidneys back online quickly
    • increase in CO and SVR before you see a1 effects (DA -> B -> a1)
    • 1-3 mcg/kg/min = dopaminergic activity
    • 3-10 mcg/kg/min = B activity
    • 10-20 mcg/kg/min = a activity
    • arrhythmogenic effects often precede sufficient vasopressor effects
    • tachyarrhythmias
  31. epinephrine
    • primarily B agonist at low doses and a agonist at high doses
    • used for pulseless cardiac arrest to restore perfusion
    • most arrhythmogenic and can shut off areas of periphery completely!
    • coronary eschemia - can cause MI
  32. phenylephrine
    • the only pure a agonist
    • little or no effect on HR - good option if severe tachycardia or tachyarrythmias
    • dose-related increase in MAP and SVR
  33. vasopressin
    • V1 receptor agonist
    • increases response to catecholamines
    • will increase urine output despite it being an ADH b/c it increases blood flow to the kidneys
    • coronary steal
    • CAD
    • myocardial dysfunction
    • used for septic shock
    • highly increases SVR
  34. dobutamine
    • mainly B1 but some B2 agonism
    • inotrope with vasodilatory properties
    • used for distributive and cardiogenic shock
    • increases CO, SV and DO2
    • tachyarrhythmias
  35. milrinone
    • PDE inhibitor
    • far more vasodilatory than dobutamine (nearly always requires concurrent vasopressor to maintain pressure)
    • inotrope with vasodilatory properties
    • used for cardiogenic shock
    • increases CO, SV, and DO2
    • highly decreases SVR
    • Hypotension
  36. steroids
    • consider when hypotension does not respond to fluids
    • hydrocortisone has the best data
    • remove as soon as not needed
    • relative adrenal insufficiency
  37. Drotrecogin alpha (Xigris) (activated protein C = APC)
    • anti-inflammatory
    • anti-coagulation
    • pro-fibrinolytic
    • very expensive
    • must start within 48h of organ dysfunction/failure starting
    • benefit: may not die
    • prophylactic UFH can be co-administered with APC (do not dc heparin)
    • can increase PT, aPTT times and increase INR
  38. How is a stress ulcer created?
    d/t shunting away of blood from the GI tract
  39. When should stress ulcer prophylaxis be given?
    • coagulopathy > 24h (plt < 50,000, INR > 1.5) or any 2 of the following:
    • neurologic trauma
    • hypoperfusion (sepsis, shock)
    • severe burns (> 35% BSA)
    • multiple organ failure
    • PMH GI ulcers/bleed within 1 yr
    • high dose steroids (> 200mg HCT eq.)
    • multiple trauma
    • postoperative transplant
  40. What agents are used in stress ulcer prophylaxis?
    • H2 blockers
    • PPIs
    • sucralfate
  41. How do pts get deep venous thrombosis (DVT)?
    damage done to vessel endothelium during invasive monitoring
  42. What agents are used in DVT prophylaxis?
    • heparin 5,000u q 8
    • LMW heparin 40mg qd (usually enoxaparin)
    • fundaparinox
    • coumadin
    • sequential compression devices
    • IVC (intravena caval) filter to catch embolism before it gets to the lungs
  43. What risks can cause ileus?
    • opioid use
    • immobilization
    • decreased blood flow
  44. What agents are used in bowel prophylaxis to prevent ileus?
    • docusate sodium
    • senna
    • bisacodyl
    • polyethylene glycol
    • Milk of Magnesia, etc.
  45. What are the stages of sedation?
    • analgesia
    • conscious sedation
    • amnesia
    • paralysis
  46. What is analgesia in the sedation cascade?
    • first and primary goal before instituting a sedative (want to know the pain is being blocked before we make them unable to tell us so)
    • always reassess before increasing any other sedative
  47. What is conscious sedation?
    • comfortable but interactive
    • anxiolysis
    • ICU psychosis
  48. What is amnesia in the sedation cascade?
    • mandatory for paralysis
    • utilize for procedures which may be unpleasant
  49. What is paralysis in the sedation cascade?
    • NOT a sedative!!!!
    • used only for rare indications
    • necessary for intubation and difficult ventilation
  50. What agents are used in sedation?
    • Morphine
    • hydromorphone
    • fentanyl
    • methadone
    • lorazepam
    • midazolam
    • diazepam
    • chlordiazepoxide
    • succinyl choline
    • pancuronium
    • vecuronium
    • cisatracurium
    • ketamine
    • chloral hydrate
    • propofol
  51. Morphine
    • agent of choice
    • onset < 5 min
    • peak in 1/2 to 1 hr
    • duration 3-7h (mostly 3)
    • may exacerbate hypotension d/t histamine release
    • may cause itching
    • decreases respiratory drive
    • decreases GI motility
  52. hydromorphone
    • not used much
    • no histamine release
    • no active metabolites
    • little cross-reactivity w/morphine
    • greater potency than morphine
    • onset 15-30 min
    • peak 1/2 to 1h
    • duration 4-5h (mostly 5)
  53. fentanyl
    • #2 analgesic (for CV unstable instead of morphine)
    • less histamine release
    • short DOA
    • no cross-reactivity w/morphine
    • lipophilic
  54. methadone
    • long terminal half-life
    • dose q 6h at low doses but may decrease to bid or qd after prolonged tx
    • lipophilic
    • high inter-patient variability
    • high risk for overdose
  55. What are the advantages of benzodiazepines in sedation?
    • sedation
    • anxiolysis
    • hypnosis
    • some amnesia
    • multiple routes of administration
    • intermittent dosing possible
  56. lorazepam
    • DOC for long-term sedation
    • glucuronidated in liver
    • good amnestic qualities
    • poor solubility
    • no active metabolites
  57. midazolam
    • preferred benzo for short-term sedation (< 72h)
    • water soluble/ lipid soluble (long term sedation if used over 72h - can't get out of it d/t depot effect)
    • quick onset 1-3 min
    • short DOA 1-3h
  58. diazepam
    • generally reserved for status epilepticus
    • very poor solubility
  59. chlordiazepoxide
    • generally used for alcohol w/d
    • many active metabolites - long DOA
  60. When are neuromuscular blockers used?
    when pt is breathing against intubation to prevent pneumothorax
  61. What concurrent therapies should be used with NM blockers?
    • eye lubrication
    • body repositioning
    • suction
    • train of four monitoring
    • anticoagulation
    • adequate sedation!!!!
  62. succinyl choline
    • depolarizing NM blocker
    • causes contraction and then you're stuck there
    • mimics ACh
    • lasts 3-5m (ideal for intubation)
    • CI in renal failure, burns, trauma
    • tachyphylaxis
    • bradycardia
    • fasciculation
  63. pancuronium
    • nondepolarizing NM blocker
    • generally 1st line agent
    • many patients cannot tolerate CV effects (hypotension and reflex tachycardia)
    • very cheap
  64. vecuronium
    • MOST USED nondepolarizing NM blocker
    • hepatically eliminated
  65. cisatracurium
    • nondepolarizing NM blocker
    • for patients with multiple organ dysfunction
    • Hoffman degradation
    • patients often require far higher doses than those recommended for infusion
  66. What is the Train of 4 testing?
    • twitch response
    • goal is 2 twitches per 4 shocks
  67. What are the other problems associated with NM blockers?
    • prolonged myopathy (inability to move)
    • critical illness myopathy (incoordination - increased risk with steroids and AGs)
  68. ketamine
    • NMDA antagonist
    • useful in peds (adults get emergence phenomenon - hallucinations, altered mood)
    • causes less respiratory depression
    • some bronchodilation (useful in asthmatics)
  69. chloral hydrate
    • NOT an ideal agent (many cases of overdose)
    • often used for conscious sedation in peds
  70. propofol
    • extremely short DOA
    • must be given as infusion - titrate to effect
    • in a lipid base - infections, pancreatitis a problem
    • used in pts needing frequent removal of sedation (brain injury pts)
    • not much amnesia
    • very sedative at proper doses
    • hypertriglyceridemia
    • hypotension
  71. What are the treatments for delirium in the ICU?
    • haloperidol
    • AAP
    • etomidate
    • dexmedetomidine
Author
giddyupp
ID
45786
Card Set
Critical Care
Description
Critical Care
Updated