General Surgery

Question 1

What happens to intestinal blood flow during shock?

Answer 1

Large arteriolar vasoconstriction and small arteriolar vasodilatation which provides preservation of flow the mucosa but decrease flow the muscularis propria.

Question 2

What happens to intestinal perfusion after initial resuscitation after shock?

Answer 2

Intestinal perfusion is still diminished

Question 3

What is the order of highest to lowerst potassium secreting organs?

Answer 3

Colon > Saliva > Gastric > Bile

Question 4

What patient medical history would make you not want to use succinylcholine for fear of hyperkalemia?

Answer 4

Burns, Trauma, spinal cord injury, and neurogenic disorders

Question 5

How much potassium is in the body?

Answer 5

50meq/kg which equals about 3500meq.

Question 6

How much potassium loss occurs when there are only 3meq/L on labs? 2meq/L?

Answer 6

Deficit of 100-200 meq/L for K of 3, and 300-600 meq/L for K of 2

Question 7

What are the clinical manifestations of metabolic acidosis?

Answer 7

Oxygen dissociation curve shift to the right, increased catecholamine release, decreased cardiac contractility, peripheral arterial dilatation

Question 8

What are the ECG changes for hypokalemia?

Answer 8

ST depression, flattening T waves, U waves

Question 9

When do ECG changes occur for hypokalemia?

Answer 9

Under 3meq/L

Question 10

What is the concentration of NA, K and Bicarb in the pancreas?

Answer 10

140, 5, and 100 because it has the same concentration of Na and K as there is in plasma and its alkalotic due to the centroacinar and intercalated duct cells

Question 11

Can you get hyperkalemia in a patient with normal kidney function?

Answer 11

No because 90% of ingested potassium is excreted in urine

Question 12

What muscles are affected by potassium changes?

Answer 12

Cardiac, skeletal and smooth muscle

Question 13

What does hyper and hypokalemia interfere with?

Answer 13

membrane depolarization and repolarization

Question 14

What ECG changes can you see with mild hyperkalemia?

Answer 14

Peaked T waves and shortened QT interval

Question 15

What ECG changes can you see with severe hyperkalemia?

Answer 15

Flattened P waves, prolongation of QRS complex, deep S waves

Question 16

What is the feared complication of hyperkalemia?

Answer 16

Ventricular fibrillation and cardiac arrest

Question 17

What can you do to treat hyperkalemia temporarily?

Answer 17

10-20% calcium gluconate, glucose and insulin, or Sodium bicarbonate

Question 18

What is the dosing for calcium gluconate and calcium chloride for hyperkalemia?

Answer 18

1000mg over 2-3minutes with cardiac monitoring. Lasts for 60 minutes

Question 19

Which calcium can go in the periphery and which in central vein for hyperkalemia?

Answer 19

Calcium chloride goes in the central vein and calcium gluconate goes in the periphery

Question 20

How do u dose the insulin and glucose for hyperkalemia?

Answer 20

10U regular insulin and 25g of glucose (50amps of D50) or 10U in 500ml of 10% dextrose

Question 21

What is considered hypophosphatemia?

Answer 21

0.8 mmol/L

Question 22

What conditions are at risk for hypophosphatemia?

Answer 22

DKA, alcoholism, Sepsis, malnutrition with carbohydrate feeding

Question 23

How does hypophosphatemia manifest?

Answer 23

Affects diaphragm contractility leading to respiratory failure

Question 24

Who should you evaluate for hypophosphatemia?

Answer 24

Patients you are weaning from vent and those with COPD

Question 25

What is the formula for FeNA?

Answer 25

(UNa x Pcr/Pna x Ucr) x 100

Question 26

What value of UNa suggests hypovolemia?

Answer 26

Una of 10-15 mEq/L

Question 27

What value of UNa suggests ATN?

Answer 27

UNa of 20meq/L

Question 28

What FeNa is considered for prerenal azotemia?

Question 29

What is the physiological response of renal hypoperfusion

Answer 29

Renin secretion from juxtaglomerular cells on afferent arterioles which produces angiotensin II, which promotes Na and H2o resorption and aldosterone secretion, and arteriolar vasoconstriction

Question 30

What fluid is best for hemorrhagic shock?

Answer 30

isotonic crystalloid solution

Question 31

What are the main symptoms of hyperkalemia of 7 or 8 meq/L

Answer 31

muscle weakness and cardiac arrhythmias

Question 32

What are the primary causes for decreased urinary excretion of potassium?

Answer 32

hypovolemia, hypoaldosteronism, renal failure, and drugs like spironolactone and NSAIDs

Question 33

Why do you get peaked T waves with hyperkalemia?

Answer 33

The increase potassium concentration causes a faster repolarization

Question 34

Why do you get flattened P waves with hyperkalemia?

Answer 34

Hyperkalemia prevents the Na channels from opening to get depolarization by decreasing the membrane potential

Question 35

What are the three things that will counterbalance hyperkalemia?

Answer 35

hypercalcemia, hypernatremia, and alkalosis

Question 36

How long does it take for IV sodium bicarb work to antagonize hyperkalemia?

Answer 36

30-60 minutes to raise pH

Question 37

How long does it take for IV insulin and glucose to work? and how much does it bring the potassium down?

Answer 37

1 hour for 0.5-1meq/L decrease

Question 38

How long does kayexalate take to work and how much does it decrease the potassium?

Answer 38

2-4 hours and by 0.5 - 1 meq/L with 50g of kayexalate.

Question 39

How does the kidney compensate for acid load? and how long does it take?

Answer 39

secreting ammonia and 2-4 days

Question 40

How long does ventilatory compensation for metabolic acidosis occur?

Answer 40

12 to 24 hours

Question 41

What should you do while treating a DKA patient with insulin and fluids?

Answer 41

Replace potassium

Question 42

How much albumin ends up in the interstitial space?

Answer 42

50%

Question 43

Why is dextrose added to hypotonic solutions?

Answer 43

to increase their tonicity and prevent red blood cell lysis

Question 44

How many meq of Sodium is in lactated ringers?

Answer 44

130meq/L