Critical care Flashcards
Describe propofol infusion syndrome
- Caused by high dose propofol drip for >24 hours, esp seen in kids
- Impairs aerobic metabolism. This then leads to skeletal and cardiac tissue injury
- Rhabdo, cardiac failure
- pancreatitis from high TG
Describe the triad for hepatopulmonary syndrome
- Intrapulmonary vascular dilation
- liver failure
- Increased A-a gradient
- PVR and PAP will not increase
- ** NO increases in these patients
What is the treatment for botulism in people > 1 year and for infants?
- > 1 year: equine serum antitoxin
2. < 1 year: human derived IG
What are conditions that are associated with an increased mixed venous O2 saturation?
- Septic shock
- cirrhosis
- Hyopthermia
- Hyperoxia
- AV fistulas (seen in late cirrhosis)
Describe the mechanism for metabolic compensation following respiratory acidosis
- In the acute phase, CO2 and H20 form HCO3 and H+. The HCO3- is exchanged for Cl-, which increases the plasma concentration of bicarbonate
- Over a longer period of time, the kidneys excrete Cl-, which then leads to reabsorption of bicarbonate
What are the metabolic changes seen with septic shock?
- Metabolic acidosis
- Increased metabolism/02 demand
- Increased cortisol –> hyperglycemia
- Decreased EtCO2 due to respiratory alkalosis
What metabolic changes are seen with initiation of TPN?
- Hyperglycemia, hyperinsulinemia
- Hypercarbia: as the body breaks down the nutrition, it can produce CO2
- Hepatic steatosis
- Hypokalemia, Hypomagnesemia, Hypophosphatemia
How do you treat TCA toxicity?
Sodium Bicarbonate, which shifts the equilibrium to the non-ionized form of the drug, making it less likely to bind to voltage gated Na channels
How does steroid myopathy present?
With proximal muscle weakness and normal CK
What drugs most commonly cause a drug fever?
- Amphotericin
- Cephalosporins
- PCN, procainamide, phenytoin
- Quinidine
What is one complication of NG tube feeds that can cause a fever and leukocytosis?
Sinusitis
When is it indicated to use hydrocortisone in septic shock?
When patients are NOT responsive to fluids or vasopressin
What effect does hypophosphatemia have on the Hemoglobin oxygen dissociation curve?
It shifts the curve to the LEFT
Does dopamine for renal protection in septic shock show a benefit of improved mortality?
NO
What are the two groups that you should NOT use colloid for resuscitation.
- Definitely in TBI patients
2. Confers no change in mortality in trauma patients, so you can use it, but there’s no benefit
What is the MOA of botulism?
Destroys the SNARE proteins that release Ach from the prejunctional membrane
When should parenteral nutrition be started? Why is enteral nutrition preferred over TPN?
What are the most common complications of TPN?
- Start TPN after 7 days
- Enteral, aka via NGT, is better because it maintains the integrity of the gut. It has a lower risk of infection and no risk of cholestasis
- TPN is associated with infection and thrombophlebitis, it is also associated with cholestasis, which isn’t as common and thrombophlebitis
Why does abrupt cessation of TPN lead to hypoglycemia?
The TPN is high in carbs, which leads to high levels of insulin. Upon cessation of the TPN, the carbs will no longer be present, and the insulin will cause hypoglycemia. It is recommended that you continue TPN in the perioperative period. If need be, you can stop the TPN, but start a glucose infusion and do frequent glucose checks.
What are the lung protective ventilator settings for ARDS?
TV 6ml/kg
Plateau pressures < 30
How do you calculate the amount of bicarbonate necessary to correct an acidosis?
- Bicarbonate = 0.2 * patient weight * base deficit (leave out the negative)
What is the treatment for hypermagnesemia?
- Stop Magnesium
- Antagonize the magnesium that is in the system with calcium
- Remove the magnesium with loop diuretics or dialysis
What are the advantages and disadvantages of ph-stat management during cooling?
Advantages: increased cerebral blood flow due to vasodilation, counteraction of the leftward shift of the O2 curve, increased speed of cerebral cooling due to the increased CBF
Disadvantages: increased risk for cerebral emboli due to vasodilation
How do you treat methemoglobinemia? How about in patients with G6PD deficiency?
- Normal patients: methylene blue
2. G6PD deficient patients: use ascorbic acid
What are the recommendations for sepsis management in regards to MAP goals, fluid management, and antimicrobial management?
- MAP goals at least 65
- Fluid: AT LEAST 30 ml/kg within THREE hours
- Antimicrobial coverage within the FIRST hour
How do you treat cyanide poisoning?
Hydroxycobalamin
What are the criteria to diagnose septic shock?
- Lactate > 2 despite fluid resuscitation
2. dependence on vasopressors to maintain a MAP of > 65
Why can antibiotics used to treat gram negative bacteria lead to hypotension?
Hypotension is caused by cleaving of the outer shell of the gram negative bacteria (lipopolysaccharide). This leads to increased antigen and an increased septic response
What is the fastest way to diagnose C. Diff?
- Toxin assay! Stool culture will take 1-2 days
