Hypoglycemia

Question 1

reduced metformin clearance is worsened by

Answer 1

lactic acidosis, metabolic acidosis, renal impairment (AKI), poor perfusion

Question 2

what is the relationship between metformin clearance and creatinine clearance?

Answer 2

proportionally decrease

Question 3

metformin toxicity symptoms

Answer 3

non-specific
ab pain, N/V, malaise, myalgia
blindness, hypothermia, hypotension, respiratory insufficiency

Question 4

mechanisms of metformin metabolic acidosis

Answer 4

1. interfere with cellular aerobic metabolism by inhibiting ETC, thus shifting to anaerobic metabolism –> lactic acidosis
2. suppresses hepatic gluconeogenesis from pyruvate, decreases hepatic pH and lactate uptake –> lactic acidosis

Question 5

metformin toxicity treatment

Answer 5

ABCDs, vasopressors, fluids
Extracorporeal treatment (intermittent hemodialysis preferred)

Question 6

When is extracorporeal treatment recommended for metformin toxicity?

Answer 6

1. lactate concentration > 20 mmol/L
2. pH =< 7
3. failure of standard supportive measures
4. comorbid conditions - shock, liver/kidney failure, decreased consciousness

Question 7

How long should ECTR be done?

Answer 7

until lactate conc < 3 mmol/L
AND
pH > 7.35

Question 8

insulin toxicity management

Answer 8

initial bolus (D10W at 75 mL/hr and titrate)
maintenance infusion (D5W or D10W)

Question 9

how to proceed transitioning off dextrose in insulin toxicity management?

Answer 9

consider measuring C-peptide (bc insulin will not be accurate)
or trial octreotide

Question 10

target BG range for maintaining euglycemia

Answer 10

100-150 mg/dL

Question 11

when to consider central venous access

Answer 11

1. dextrose conc greater than or equal to D10W
2. large volume administrations

Question 12

what to monitor for peripheral

Answer 12

glucose every 30 min to 1 hr initially, then less frequently
serum phosphate levels
serum potassium levels

Question 13

maximum peripheral dextrose concentrations (IV bolus)

Answer 13

adult = D50W
children = D25W
infants = D10W

Question 14

which hypoglycemia causing agents are highly protein bound and cannot be removed via dialysis?

Answer 14

sulfonylurea (glimepiride, glipizide, glyburide)

Question 15

sulfonylurea MoA

Answer 15

1. inhibit K+/ATP channels on beta cells –> prevents efflux of K
2. cellular depolarization
3. calcium influx via opening of Ca channels
4. insulin release

Question 16

how does sulfonylurea toxicity cause prolonged hypoglycemia?

Answer 16

long duration of action causes prolonged cell depolarization, thus prolonged insulin release

Question 17

in sulfonylurea toxicity, how long is the delayed onset of hypoglycemia

Answer 17

1st gen = up to 48 hrs
2nd gen = up to 24 hrs

Question 18

sulfonylurea toxicity: further insulin release after dextrose infusion can cause

Answer 18

rebound hypoglycemia

Question 19

sulfonylurea toxicity causes failure of counterregulatory mechanisms such as

Answer 19

adrenalin, cortisol, growth hormone, glucagon

Question 20

sulfonylurea toxicity management

Answer 20

ABCDs, activated charcoal, dextrose (only for correction), octreotide (for maintenance)

Question 21

octreotide MoA

Answer 21

mimics somatostatin, inhibits release of insulin, glucagon, secretin, motilin by decreasing cytoplasmic calcium

Question 22

octreotide dosing

Answer 22

50 mcg as single dose SUBQ/IV
repeatable every 6 hours

Question 23

octreotide dosing for refractory hypoglycemia

Answer 23

continuous infusion up to 125 mcg/hr

Question 24

when to use octreotide

Answer 24

when euglycemic and high risk for prolonged, delayed, or rebound hypoglycemia

Question 25

octreotide AE

Answer 25

N/V/D, ab pain, injection site pain, sinus bradycardia, hypertension, cholelithiasis, necrotizing enterocolitis, glucose dysregulation

Question 26

octreotide monitoring

Answer 26

observe patient up to 24 hrs after last dose
if asymptomatic, observe in hospital 12-24 hrs
do not discharge pt at night

Question 27

conditions that cause hypoglycemia

Answer 27

hepatic cirrhosis, chronic kidney disease, alcoholism, sepsis, burns, AIDS, Addison’s Disease, sarcomas/carcinomas

Question 28

xenobiotics that cause hypoglycemia

Answer 28

beta blockers, ethanol, fluoroquinolones, GABA agonists, haloperidol, MAOis, salicylates, sulfonamides

Question 29

glucagon dosing

Answer 29

1 mg IM/IV/SUBQ

Question 30

glucagon AE

Answer 30

N/V (IV more than IM)
adrenergic surge - tachycardia, hypertension

Question 31

dextrose bolus dosing

Answer 31

0.5-1 g/kg IV bolus

Question 32

maximum peripheral dextrose bolus concentration (adults and pediatrics)

Answer 32

D10W

Question 33

rule of 15

Answer 33

15 g of glucose intake, wait 15 min, recheck blood glucose
improvement seen in 15 minutes, if not, repeat

Question 34

risk factors of hypoglycemia

Answer 34

age over 65
polypharmacy (for diabetes, coingestions)
frequent hospitalizations
long-acting agents
impaired drug clearance

Question 35

in hypoglycemia, BG level is

Answer 35

< 60 mg/dL

Question 36

symptoms of hypoglycemia

Answer 36

decreased alertness, fizziness, confusion, seizures, tachycardia, pallor, bizarre behavior

Question 37

ABCDs

Answer 37

airway, breathing, circulation, disability, exposure