DO ELEVENTH: Hypoglycemia

secreted by the alpha cells of the islets of langerhans

glucagon

main function of glucagon

increase blood glucose concentration

glucagon promotes a _____ state

hyperglycemic

what is another hormone that counteracts insulin

epinephrine

Glucagon and Ephinephrine have counter regulatory effects within

minutes

these hormones can also promote gluconeogenesis but their effects are a bit more delayed in terms of hours to days

growth hormone and cortisol

T/F glucose is the only nutrient that normally can be used by the brain, retine and germinal epithelium of the gonads

T

most glucose formed by gluconeogenesis during interdigestive period is used for

brain

concerning hypoglycemia =

persistent values <60mg/dL

clinical signs of hypoglycemia are dependent on

severity of hypoglycemia

rate of glucose decrease

animals adaption

the first clinical sign of hypoglycemia that is often overlooked

hunger

why is there hunger with hypoglycemia

body is trying to comboat low level hypoglycemia

the clinical signs that occur related to release of adrenal catacholemines

tremors

hunger

nervousness

panting

tachycardia

neuroglycopenia clinical signs include

seizures

weakness

stupor

ataxia

T/F clinical signs of neuroglycopenia occur with sevre hypoglycemia

T

seizures/stupor/come is rare is BG>

45mg/dL

T/F BG<50-60 probably requires tretament because they are at risk of having clinical signs

T

in the acute setting of hypoglycemia how do we treat

dextrose bolus followed by some degree of dextrose in their IV fluids

the bottom line is you have to identify and address

the underlying cause of hypoglycemia

big categories for differentials of hypoglycemia

artifact

drug/toxin

excess glucose consumption

decreased glucose production

excess insulin

very common cause of non artifactual hypoglycemia

excess insulin or insulin like factors

T/F artifactual hypoglycemia is very common

T

what can cause artifactual hypoglycemia

serum harvest delay

extreme leukocytosis or erythrocytosis

false glucometer reading

one big cause for hypoglycemia hospitalization

insulin overdose, administered insulin dose too high

other drugs that can caus ehypoglycemia

oral hypoglycemic drugs

ethanol

major toxin that causes hypoglycemia

xylitol

why does xylitol cause hypoglycemia

dogs recognize it as sugar and hyper secrete insulin

a classic example of excess glucose consumption

sepsis

why does sepsis cause excess glucose consumption

big inflammatory response causes poor tissue perfusion and vasodilation and tissues have to do anaerobic metabolism which requires a lot of glucose

large ____ tumors consume large quantities of glucose

hepatocellular

this syndrome we are unclear if hypoglycemia is the cause of collapse

exercise induced hunting dog collapse

what is something that instead of increased glucose consumption we see decreased glucose production

transient juvenile hypoglycemia

who do we see transient juvenile hypoglycemia in

mini or toy breed puppies <6 months usually <3-4 months

what is the physiology behind toy breed puppy hypoglycemia

young growing dogs that do not have have adequate glycogen reserves

usually toy breed puppy hypoglycemia is seen in many dogs that are compromised by

comorbid conditions

what syndrome can we see decreased glucose production in

hypoadrenocorticism

the liver is the primary site for glycogen stoagre so with advanced liver disease what can we see

hypoglycemia

whata re some uncommon causes of decreased glucose production

fasting/malnutrition or pregnancy

hypopituitarism or growth hormone deficiency

glycogen storgae disease

what can cause excess secretion of insulin

extra pancreatic tumor

these are neoplastic proliferation of beta cell tissues

insulinomas

insulinomas secrete

insulin

what things can narrow down your differentials

good history

consideration of signalment

routine lab evaluation

in a normal dog or cat insulin secretion is inhibited when glucose is less than

60-80mg/dL

insulin secretion from neoplastic beta cells is independent of

blood glucose concentration and persist despite low blood glucose concentration

_______ neoplasia is the most common islet-cell neoplasia in dog

beta-cell

T/F beta cell neoplasia is still uncommon in the dog and rare in the cat

T

age we see beta cell neoplasia in

middle age to older dogs

most if not all insulinomas are

malignant

T/F no matter what we do we probably are not curing beta cell neoplasia

T

most common sites of metastases in this neoplasia

lymph nodes and liver

clinical signs of insulinoma

seizure

collapse

weakness

trembling

usually with insulinoma the initally signs are missed and most animals present for signs of

neuroglycopenia

clinical signs of insulinoma are

episodic

why are clinical signs of insulinoma episodic

insulinomas sporadically hypersecrete insulin, will have a period of neuroglycopenia and then be normal

some owners report feeding may _____ or ______ clinical signs

alleviate or exacerbate

why is diagnosing insulinomas hard

the dogs arent always hypoglycemic and often you have to fast the dog

on diagnosis of insulinomas what is diagnostic in terms of plasma insulin and glucose levels

low glucose with high insulin

T/F if a dog has normal to high insulin levels in the face of a hypoglycemia that is clearly inappropriate insulin secretion

T

it is critical that a _____ is present when measuring insulin levels to diagnose

hypoglycemia

most insulinomas are _____ size and may escape detection by US or CT

pea

T/F at the time of surgical removal micrometastasis has usually already occured

T

T/F just because you do not see evidence of a mass in the pancreas does not exclude the fact that a mass may be present

T

in the acute setting how do we treat insulinoma

dextrose IV, shoot for low-normal glucose conc

T/F in dogs with insulinomas we are very cautious to avoid overcorrection because if we overcorrect we are likely going to stimulate even more insulin hypersecretion

T

in the acute setting we are trying to alleviate

clinical symptomology

long-term management of insulinoma

removal of tumor

T/F despite metastases removal of the tumor is effective in the short term

T

10% of dogs develop ______ after tumor removal

diabetes

10% of dogs develop ______ post op

pancreatitis

why is removal of tumor recommended even though there is metastasis

by removing bulk of the disease you will dramatically improve clinical signs

what do we do to modify the diet of dogs with insulinomas

small frequent meals high in proteins fats and complex carbs

avoid sumple sugars

what is a mainstay of medical therapy for dogs with insulinoma that will counteract the effects of insulin

prednisone (stimulate glucagon secretion, increases gluconeogenesis)

when treating dogs with insulinomas with either post surgery or dogs not getting surgery it is

diet and prednisone

what is a second or tertiary option for dogs that start to fail other therapies

streptozocin

median survival time of dogs with insulinomas

6-14 months

if you only do diet and pred what is survival time

6 months

if you only do surgery what is ST

1 year

if you do surgery and diet and pred result in

longest survival times after diagnosis

dogs that are ______ generally have a poor prognosis

young, insulinomas are more aggressive

having _______ post op is a poor prognostic indicator

hypoglycemia

if dogs are hyperglycemia after surgery that is

a good prognostic indicator

T/F overall this is a fatal tumor animals are likely to die from but for 6months to a year we can get good clinical control

T