Lecture 17 4/10/25 Flashcards
What should be considered when choosing an insulin for a patient?
-expense
-availability
-ease of use
-dosing accuracy
-owner goals; SID vs BID, remission, etc.
What is the expense breakdown for insulins used in dogs?
-glargine: $$$-$$$$
-prozinc: $$$
-vetsulin: $$
-degludec: $
-NPH: $
Which insulins are most to least likely to achieve SID dosing in dogs?
-degludec: 85%
-glargine: 50-72%
-prozinc: 60%
-vetsulin: 30%
What is the expense breakdown for insulins used in cats?
-glargine: $$$-$$$$
-prozinc: $$$
-vetsulin: $$
What considerations need to be made for cats?
-whether remission is likely
-whether a loose or tight control/monitoring strategy will be used
What are the characteristics of starting at home insulin?
-want a stable, uncomplicated patient that can tolerate outpatient SQ injections
-typically control dogs with 0.2 to 1 U/kg BID
-typically control cats with < 5U/cat BID
What are the starting insulin doses for cats and dogs?
cats:
-1 U/cat SQ BID
dogs:
-SID: 0.5 U/kg SQ
-BID: 0.25 to 0.5 U/kg SQ
What are the characteristics of follow up once a patient is started on at home insulin?
-takes time to adjust to a change in insulin dose/type
-can do monitoring after first dose and decrease if BG drops under 150 mg/dL
-should re-evaluate every 7 to 14 days until stable on dose; then every 3 months
-can use constant glucose monitoring devices to be more aggressive with dose escalation
-CGM must be used for animals on basal insulins
What clinical signs should be monitored in patients on insulin treatment?
-PUPD
-appetite
-weight
-attitude/activity
What are the characteristics of insulin dose changes?
-based on owners reports of clinical signs and/or vet’s perception of glycemic control
-typically increase or decrease dose by 10 to 20% at a time
What should NEVER be used as a measure of whether or not to change the insulin dose?
spot glucose checks
What is diabetic control?
-absence of clinical signs of hypoglycemia
-mean BG is lower than renal threshold
-NOT trying to get normal BG all the time; short periods of hyperglycemia are acceptable and expected
What are the characteristics of fructosamine measurement?
-glycosylated albumin that represents average BG for 1 to 2 weeks
-significant changes are >/= 50 umol/L
-normal ref. range is for non-diabetics; diabetics measuring in this range likely have chronic hypoglycemia
What are the limitations of fructosamine?
-can be falsely increased by hypothyroidism
-can be falsely decreased by hypoalbuminemia
-cannot identify hypoglycemia
-can be normal with early onset or mild DM
-might be discordant with clinical signs
-better for diagnosis of diabetes than determining glycemic control
What are the goals when assessing a BG curve?
-determine response to insulin/diet
-determine duration of insulin response
-identify risks of low BG
What is the glucose nadir on a BG curve?
the lowest glucose measurement throughout the curve
What is the time point at which the glucose nadir occurs called?
time to peak insulin effect
What are the limitations of an intermittent BG curve?
-affected by stress; hospitalization, restraint
-labor intensive
-multiple needle sticks
-questionable client compliance
-large day-to-day fluctuations; esp. with insulin suspensions
-can miss periods of hypoglycemia
What are the characteristics of the FreeStyle Libre CGM?
-small, lightweight sensor
-can detect glucose enzymatically or amperometrically
-measures interstitial glucose every minute
-detects a range of 40 to 400 mg/dL
-connects to phone app via bluetooth
-each sensor stays on 14 to 15 days
What are the most important points regarding monitoring in DM patients?
-interpret all monitoring modalities together
-DM is probably well controlled if no clinical signs and stable weight
-spot BG checks not reliable for monitoring; need at least an intermittent curve, CGM is best
-BG monitoring is only way to identify hypoglycemia
-insulin dose must be decreased if hypoglycemia exists
-stringent BG control is not as critical as in human medicine
What causes a shift to diabetic crisis?
-insufficient insulin
-increased glucagon
-shift to using fat instead of glucose for energy
What are the characteristics of diabetic ketosis?
-diabetes + ketones
-may have systemic illness or may be asymptomatic
What are the characteristics of diabetic ketoacidosis?
-diabetes + ketones + metabolic acidosis
-will have signs of systemic illness
-can occur in newly diagnosed DMS or previously stable DMs with complications
-should always look for pancreatitis, bacterial infections, and hormonal disorders
What are the characteristics of hyperglycemic hyperosmolar syndrome?
-diabetes + no/low ketones + severe hyperglycemia + high serum osmolality
-will have signs of systemic illness and neurologic signs
What are the treatment goals in diabetic crisis?
-restore fluids
-normalize electrolytes before giving insulin
-normalize metabolism/stop ketone production with insulin +/- dextrose
-frequently monitor
What is the ideal fluid therapy in a diabetic crisis?
aggressive rehydration for 6 to 8 hours with a balanced crystalloid and potassium +/- phosphorus supplementation
What are the benefits of fluid therapy in diabetic crisis?
-optimize cardiac output and tissue perfusion
-correct electrolytes before giving insulin
-promote glucosuria
-promote ketonuria to improve acidosis
What causes hypokalemia in diabetic crisis?
-decreased intake (anorexia)
-increased urinary loss from osmotic diuresis
-transcellular potassium shift
What are the side effects of hypokalemia?
-generalized muscle weakness
-cervical ventroflexion (cats)
-inability to stand
-difficulty expanding chest wall
-gastroparesis/ileus
-urine retention
-reduced cardiac function/arrhythmias
Why does diabetic crisis affect intracellular potassium?
acidosis causes H+ ions to shift into the cells in exchange for potassium
Why is it important to have a normal serum potassium before giving insulin?
insulin admin. will drive potassium intracellularly
What are the clinical signs of hypophosphatemia?
-weakness
-neurologic signs
-hemolysis
When can a decreased serum phosphate be anticipated?
-after insulin therapy
-with feeding
When does hypomagnesemia need treatment?
-severe DKA
-refractory hypokalemia
-arrhythmias
Why does acidosis not typically require special treatment?
it will often correct with fluid therapy
What are the characteristics of regular insulin use in diabetic crisis?
-crystalline insulin that is fast acting
-various protocols; hourly IM intermittent IM then SQ, or low dose IV CRI
-initial goal is slow decrease in BG
-want to decrease BG 50 to 100 mg/dl/hr
What is the consequence of reducing the BG too quickly?
cerebral edema
Why is dextrose given with insulin in patients with BG less than 250 mg/dL?
-insulin administration is needed to resolve ketotic state
-dextrose allows for insulin administration without driving patient’s BG too low
What are the steps to getting the diabetic crisis patient discharged?
-typically need 12 to 24 hours in hospital to correct hyperglycemia
-typically need 48 to 72 hours in hospital to correct ketosis
-want to transition patient to longer-acting insulin once stable, eating, and electrolytes are normal
