Physiology Clinical Rounds

Front 1

What effect will tetrodotoxin have on the body's excitable cells?

Back 1

The voltage sensitive sodium channels will be blocked and action potentials will not be produced.

Front 2

What are some o fthe symptomatic effects of hyperkalemia?

Back 2

High serum potassium concentrations and muscle weakness.

Front 3

If a solution is added to RBCs and they lyse, what can be said of the osmolarity of the solution?

Back 3

It is hypotonic.

Front 4

What quality must a drug have if it is to be used intracellularly?

Back 4

In order to improve the permeabilty through the lipid bilayer it must have an oil/water coefficient partition.

Front 5

If an individual is poisoned by a substance that inhibits the cells Na+-K+-ATPase, what will become of the Na, K and Ca+ concentrations?

Back 5

There will be:
1. Increase in sodium intracellular
2.Decrease in intracellular K+
3. Increase in intracellular calcium from a decreased sodium gradient.

Front 6

What would be the effect on an animals vision if a transection is made in the single optic nerve?

Back 6

Ipsilateral blindness

Optic tract- Homonymous contralateral hemianopia
Geniculocalcarine tract- Homonymous hemianopia with macular sparing

Front 7

In muscular tetanic contractions of skeletal muscle, which ion is responsible for this?

Back 7

Ca+ is responsible for the tetany. It would have to be at very high levels due to constant release by the sarcoplasmic reticulum from the constant stimulation the muscle fibers are receiving, and it is not being reaccumulated.

Front 8

What is the effect of an acetylcholinesterase inhibitor?

Back 8

Acetylcholine degradation would be blocked. It would produce a larger end plate potential.

Front 9

What is Rigor mortis?

Back 9

Rigor mortis is brought on due tot he lack of ATP. After death, the regeneration of ATP is halted. The myosin and actin in skeletal muscles remain tightly bound, resulting in a very rigid state.

Front 10

When a substance blocks a potential propagation at an autonomic ganglia but is not blocked at the neuromuscular junction, what type of substance is this likely to be?

Back 10

Hexamethonium. It is a nicotinic antagonist at the ganglion, but has no effect at the neuromuscular junction.

Front 11

What is the symptomatic result if the left thalamic nucleus is destroyed?

Back 11

There will be no sensation on the right side of the body.

Front 12

On an MRI scan a mass is found on the sella turcica. The patient is complaining of headaches and blurry vision. Which structure is likely involved to produce these symptoms?

Back 12

The optic chiasma.

Front 13

Amiddle age man presents with with a new vision deficit in the right eye. When the left eye is examined, both pupils constrict, while on exam of the right eye both pupils dilate. When the light is moved from the left eye to the right, the right eye dilates. Where is the lesion likely to be?

Back 13

The right retina or optic nerve.

Front 14

What is the result of a severe Vitamin A deficiency?

Back 14

Night blindness (Nyctolopia)

Front 15

If you spin sharply to the right,"", stop and then fall, what immediately happens in the vestibular system?

Back 15

The cupula in the left horizontal semicircular canal moves towards the utricle and bends the stereocilia toward the kinocilium, resulting in the depolarization of the hair cells.

Front 16

What is a Pancoast tumor?

Back 16

These can be found on chest X ray and CT scans. They are lesions on the right apex. These are carcinomas. Patients present with a cough which is dry, weight loss, lack of sweating and vision problems. The tumor is compressing her sympathetic cervical ganglion causing Horner's syndrome, miosis, ptosis and anhydrosis.

Front 17

If the cribiform plate is fractured, one may lose the sense of smell, known as hyposmia. Why is this?

Back 17

The fractured cribiform plate has likely severed some of the input fibers to the olfactory bulb and produced the hyposmia.

Front 18

If one listens to very loud music often, with heavy bass, which part of the basilar membrane in the ear is at risk for damage?

Back 18

The apices, which detect lower frequencies.

Front 19

If one burns a finger, what causes the extension of the other arm?

Back 19

The cross extension reflex, which is part of the flexor withdrawal reflex and helps to maintain balance.

Front 20

A young man injures his spine. As a result his legs are flaccid and reflexes cannot be obtained. What has happened?

Back 20

The patient is experiencing spinal shock. he has lost excitatory stimulation from both alpha and gamma motorneurons. He may gain partial recovery in time.

Front 21

A middle aged man slips and hits his head hard. He is examined and cannot speak or write, but understands commands. What type of injury has occurred?

Back 21

He has motor aphasia, as a result of damage to Broca's area.

Front 22

A patient has a mean arterial pressure(MAP) of 70mm/Hg, a right atrial pressure(RAP) of 10mm/Hg and a total peripheral resistance(TPR) is determined to be 10mm/Hg. What is his cardiac output(CO)?

Back 22

CO= MAP-RAP
_____________
TPR

CO= 70-10
-----------
10mm Hg min/L = 6L/min

Front 23

An elderly woman has bilateral carotid bruits that are audible with auscultation. What is the physiological mechanism for the increased turbulence that creates this phenomenon?

Back 23

Increased blood viscosity due to the narrowed vessel will increase the turbulence.
In comparing older patients to younger ones, the stressed volume will decrease since the capacitance of the arteries decreases with age.

Front 24

What type of heart block is present when an ECG shows P waves that are unassociated with the QRS complexes?

Back 24

Third degree block.

Front 25

If an ECG reveals no P wave, but normal QRS and T complexes, where is the pacemaker of the heart located?

Back 25

The A-V node.

Front 26

A man working with a live wire shocks himself. Just before the shock his ventricles were in systole. Why do they not contract again from the shock?

Back 26

The ventricles are in the absolute refractory period.

Front 27

What type of effects will an ACh-anaolgue drug have on an individuals heart rate and conduction rates?

Back 27

Parasympathetic stimulation will be mimicked.
Decreased heart rate
Decreased conduction through the A-V node
Increased P-R interval.

Front 28

An individual is accidently stabbed in the abdomen. What will be the response of his autonomic nervous system?

Back 28

Increased sympathetic stimulation of the heart and vasculature
Decreased parasympathetic stimulation of his heart.

Front 29

If a baby is born with a ventricular septal defect, what can one conclude about the blood flow out of the heart, if the left ventricular pressure is greater thasn that of the right?

Back 29

Pulmonary blood flow is greater than aortic blood flow from the left to right shunt that is present.

Front 30

After angioplasty a patients left anterior descending coronary artery,it is observed that the radius has doubled. What will be the change in resistance?

Back 30

It will decrease by a factor of 16.
Remember:
Hypothetically, a 1mm size artery moves blood at 1mm/sec.
A 2mm artery will move blood at 16mm/sec (2(4).
A 3mm artery will move blood at 81mm/sec (3(4).

Front 31

After suffering from severe total body burns a young woman is brought into emergency with grossly edematous limbs. What is causing the edema?

Back 31

Increased permeability of the capillaries to water(increased K+) from damage suffered by the burns.

Front 32

After being put on a certain medication, a patient experiences orthostatic hypotension. Why is this happening?

Back 32

This is a result of a carotid sinus bradycardia response.

Front 33

After a patient has a stroke, what is the stimulus that causes the body's response to preserve blood flow to the brain?

Back 33

PCO2 in brain tissue, which increases with cerebral ischemia.

Front 34

In a 5 year old patient on a heart exam, should a third heart sound be suspicious?

Back 34

No. It is normal in children, but suspicious in adults.

Front 35

Describe the symptoms of atrial fibrillation in a middle aged woman.

Back 35

Possible chest discomfort and a feeling of light headedness. There is usually as well an irregularly irregular pulse.

Front 36

After being stabbed in the chest, a young man begins to bleed into his pericardium. What happens to the cardiac output and pressure in his heart chambers?

Back 36

Cardiac output decreases. The pressure equalizes in all 4 chambers.

Front 37

What happens in emphysema within the lungs?

Back 37

As an obstructive lung disease, there is a reduction in lung diffusion capacity for CO. (DLCO)

Front 38

What would pulmonary function tests look like(PFTs) in a 75 year old ex smoker?

Back 38

Decreased FEV
Decreased FEV1
Decreased forced vital capacity(FVC)
Increased total lung capacity

Front 39

A 50 year old female with severe scoliosis and no history of tobacco use complains of dyspnea. What category of lung disease does she have?

Back 39

Restrictive lung disease.

Front 40

A 45 minute old neonate born to an 18 year old at 27 weeks gestation is noted to have central cyanosis. respirations are shallow and rapid at 65/min. There is nasal flaring, audible grunting and duskness with intercostals and subcostal retractions. Fine rales are heard over both lung bases. His cyanosis is not improved with nasal O2. A chest X-ray reveals fine granularity, especially in the lower lobes. Arterial blood gases reveal hypoxemia with metabolic acidosis. What is the cause of this condition?

Back 40

Decreased production and secretion of surfactant resulting in atalectasis and shunting(perfused but not ventilated alveoli).

Front 41

How do pulmonary function tests differ in a patient with scoliosis from those with parenchymal disease and associated restrictive lung disease?

Back 41

The DLCO(diffusion capacity for CO) is normal in a patient with scoliosis, whereas it is reduced in a patient with parynchemal disease.

Front 42

What class of antihypertensive drugs should patients with asthma avoid?

Back 42

Non selective beta blockers (atenolol).

Front 43

A 52 year old male with interstitial lung disease with resting ABG: pH 7.45, PaO2-60mm/Hg and PaCO2-30mm/Hg. after walking on a treadmill for 5 minutes , another ABG was taken with PaCO2 30mm/Hg. what is causing the worsening hypoxemia?

Back 43

Diffusion abnormalities. In interstitial lung disease, where lung parynchyma is affected, diffusion is important during exercise.

Front 44

A young man is in an auto accident and suffers trauma leading to diaphragmatic paralysis. What changes occur in his blood gases during his injury?

Back 44

Global hypoventilation
pH decreases
PaO2 decreases
PaCO2 increases
A-a gradient is unchanged.

Front 45

What is a very frequent cause of hypoxemia found in the clinical setting?

Back 45

ventilation-Perfusion mismatch (V/Q).

Front 46

An elderly female, hospitalized for knee replacement surgery, was found on post-op day 5 with a 3 day fever, productive cough, and upper airway congestion. An X-ray finds localized infiltrates in the right middle lobe suggestive of pneumonia. What would the resting ABG look like if one were done?

Back 46

This patient likely has shunting due to probable pneumonia.
Increased pH
PaO2 decreased
PaCO2 decreased
A-a gradient is widened.
Hypoxemia does not respond to increased FiO2.

Front 47

An X-ray is done on a 22 year old who suddenly is complaining of sharp chest pain and some dyspnea. He says there have been no recent fevers or coughs. There is a moderate size pneumothorax at the left apex. What happened to the lung?

Back 47

The lung collapsed inward and the chest wall shifted outward.

Front 48

How does CO poisoning affect arterial O2 concentration?

Back 48

It decreases it.

Front 49

A 68 year old male is suffering from severe dyspnea. he was a very heavy smoker. he is using his accessory muscles to breath. Pulse oximetry reveals a reading of 86%. Why must O2 be cautiously administered in this patient?

Back 49

This patient has severe COPD. He is also hypercapneic. he is probably dependent on his hypoxic drive(via the carotid and aortic chemoreceptors) to stimulate respiration rather than CO2 level. If the hypoxic drive is withdrawn by giving o2, the patient may become apneic, causing the arterial PO2 to drop and increase PCO2. breathing may not restart because the increase in PCO2 will further depress his respiratory center.

Front 50

How does anemia affect PO2?

Back 50

Decreased mixed venous PO2.

Front 51

How may mixed venous PO2 be increased?

Back 51

Increase O2 delivery
Increase O2 content of inspired air
Increase myocardial work(Increase stroke volume)
Increase intravascular volume.

Front 52

A young woman returns from South America. On her returning home she developed some diarrhea. How will this affect her fluid distribution?

Back 52

Diarrhea:- ECF decreases with no change in the osmolarity. No change in the volume of the intracellular fluid.

Front 53

What will happen if John gives his healthy friend injections of isotonic saline. Consider the fluid compartments.

Back 53

The osmolarity of the fluid isd the same compared to that of the body fluids, so it will stay in the ECF. The volume of the ECF increases with no noted change in the ICF.

Front 54

How are body fluid compartments affected if one consumes many salted snacks with minimal to no water intake?

Back 54

Too much salt(NaCl) intake, this will increase the osmolarity of the ECF, thus drawing the fluid out of the ICF into the ECF. The result will be a decrease in volume of the ICF and an increase in volume of the ECF, while augmenting the osmolarity of both ICF and the ECF.

Front 55

What type of fluid changes are noted with adrenal insufficiency?

Back 55

Adrenal insufficiency results in a loss of NaCl, so ECF osmolarity decreases and the volume of the ECF also diminishes. Water will now move into the ICF until the osmolarity of the ICF and ECF are the same, raising the volume of the ICF and decreasing the ECF.

Front 56

What is the fluid versus osmolarity body composition of a patient with SIADH?

Back 56

SIADH-syndrome of inappropriate antidiuretic hormone, results in the retention of free water by the kidneys. This will cause a net decrease of osmolarity of both the ICF and ECF. Both volumes increase equally.

Front 57

Describe the chasnge in body fluid dynamics when does little drinking and due to high environmental temperatures sweats profusely.

Back 57

Sweat contains more water than salt, so there will be a net hyperosmotic volume contraction. The ECF volume will diminish, and the water will move out of the ICF leading to increased ICF osmolarity until it is the same as the ECF osmolarity. There is still a net ICF and ECF volume loss with increased osmolarity of ICF and ECF.

Front 58

In which syndrome is the charge barrier lost and what are the consequences?

Back 58

Nephrotic syndrome with resulting albuminuria, hypoproteinemia, generalized edema and hyperlipidemia.

Front 59

A young lady returns from a trip overseas. She returns home with severe diarrhea. An ABG is done and shows the following values: pH= 7.2, PCO2=25, HCO3=8mEq/l.More tests show Na+ to be at 135 and Cl to be 118. What is the anion gap of theis patient? What is this patient suffering from?

Back 59

Anion gap= Na+ - Cl- + HCO3.
135-115+8 =12. This anion gap result is actually normal. With a low pH, it is either metabolic or respiratory acidosis. Since the PCO2 is normal and the HCO3 is low, it is a metabolic acidosis that is probably secondary to her diarrhea.

Front 60

A middle aged man that is complaining of frequent urination with infrequent headaches visits her PCP. His plasma osmolarity is found to be 270mOsm/L, Can a diagnosis be made?

Back 60

Yes. It is SIADH. The plasma osmolarity is lower than normal yet the urine osmolarity is still is high. This is not a normal physiological response and is suggestive of SIADH.

Front 61

A research volunteer is injected with PAH(paraaminohippuric acid) for the purpose of measuring renal plasma flow.Plasma concentration of PAH is 2mg/ml, urine concentration of PAH is 500mg/ml and the urine flow rate is 1 mL/min. Determine the RPF.

Back 61

Equation for calculation is:
RPF=C(PAH)=U(PAH) X V/P(PAH).
RPF= 500mg/ml X 1mL/min/2mg/mL =250mL/min

C= urine concentration
U= Urine flow rate
P=Plasma concentration

Front 62

A 50 year old man is complaining of a severe left sided flank pain. he has a ureteral stone. hoe will this stone affect his GFR, RPF and filtration fraction?

Back 62

GFR will decrease due to the increased pressure in Bowman's space. There is no change in RPF because there is no change in the blood flow to or from the kidneys. The filtration fraction will decrease because GFR has decreased and RPF has remained unchanged.

Front 63

Regarding a drug that causes constriction of afferent renal arterioles, how will this affect the filtration fraction?

Back 63

It will remain unchanged. Even though there will be a decrease in renal plasma flow (RPF) there will be also a decrease in GFR from a drop in P(gc).
Pgc = hydraulic P in glomerular capillary (pushing blood out of capillary)

Front 64

Name a frequently use cardiac drug that that can cause hyperkalemia?

Back 64

Digitalis. It blocks the Na+-K+ pump.

Front 65

When a patient is on loop diuretics, how does this affect the urinary secretion of calcium?

Back 65

It increases. Loop diuretics inhibit Na+ reabsorption, which is coupled to Ca+ reabsorption.

Front 66

If a persdon consumes excess water, what effect does this have on the osmoreceptors in the anterior hypothalamus?

Back 66

They are inhibited.

Front 67

List one condition where ADH would be ineffective.

Back 67

Nephrogenic diabetes insipidus.

Lithium can also cause ADH to become ineffective.

Front 68

A 60 year old man presents to his doctor with severe tinnitus. On exam, he has rapid breathing, and an ABG showed a PCO2 of 24. Labs were as follows:
Na+ 140
K-5Cl-105
HCO3-15
BUN-43
Creatinine-1.7
Determine the acid base disturbances. Can drugs cause these disturbances?

Back 68

Calculate anion gap
Na+-Cl + HCO3 =140 (-105 +15 =20==metabolic acidosis with anion gap.

Calculate response to acidosis
For every mEq/Ldrop in HCO3, there should be a compensatory drop of 1.3mm/Hg of PCO2.
Normal bicarbonate is 24 so there is a drop of 7 mEq/L, so there should be a drop of 9.1mm PCO2(normal value of PCO2 is -40mm/Hg. Therefore PCO3 should be 40-9 =31mm/Hg.
The lower pCO2 then calculated indicates that she also has a respiratory alkalosis. Salicylates can cause both of these conditions.

Front 69

A patient with constant rflux. tests show a decrease in pH of the stomach and hypertrophy and hyperplasia of the gastric mucosa. A certain tumor is diagnosed that secrets a certrain hormone. What hormone is being secreted?

Back 69

Gastrin. Gastrin increases H+ secretion by the gastric parietal cells and to stimulate the groth of the gastric mucosa.

Front 70

The following mixtures are ingested by a volunteer:Mixture 1-small peptide and amino acids,Mixture 2-Fatty acids, 3-Triglycerides.After each mixture, the patients level of CCK is measured. Which mixture will have no effect on CCK levels?

Back 70

Mixture 3, because triglycerides do not cross the intestinal cell membranes.

Front 71

What effect does somatostatin have on GI hormones?

Back 71

Somatostain inhibits the release of all GI hormones and also inhibits gastric hydrogen ion secretion.

Front 72

A 40 year old doctor is telling her doctor that she is having between 8 and 10 watery stool bowel movements per day. she has pain in her upper abdomen and back. She is hypercalcemic, hyperglycemic and has hypokalemia. She has a hormone secreting tumor. What hormone is being secreted?

Back 72

VIP. This is a VIPoma. VIP is a strong stimulator of cAMP productionin the gut. This leads to a large secretion of water and electrolyte(potassium). This may be associated with multiple endocrine neoplasia, (MEN) 1 syndrome.

Front 73

What substance results in a powerful contraction of the gallbladder?

Back 73

CCK. It also is responsible for the relaxation of the sphincter of Oddi.

Front 74

A certain toxic substance has been found to inhibit the Na+ K+ pump in the basolateral membrane of the GI tract. How will this affect the absorption of glucose and galactose?

Back 74

Glucose and galactose are absorbed through the sodium dependent cotransporter in the luminal membrane. if the Na+ potassium pump is inhibited, then the sodium gradient is destroyed, resulting in inhibition of glucose and galactose absorption.

Front 75

How exactly does V. cholerae cause diarrhea?

Back 75

It secretes a toxin that activates adenylate cyclase which increases cAMP. The increased intracellular cAMP results in the opening of the Cl- channels in the luminal membrane. The flow of Cl- out of the cell into the GI tract is accompanied by Na+ and H2O. The result is secretory diarrhea,

Front 76

if a toxin is accidently ingested that damages the epithelial cells of the intestinal brush border. Which enzymes will be affected?

Back 76

Trehalase
Peptidase
a-Dextrinase
Isomaltase/sucrase
Lactase
Maltase
Proelastase

Pepsin is found in the stomach. Trypsin is found in pancreatic secretions. neither of these enzymes will be affected.

Front 77

What is the Schilling test?

Back 77

This test is conducted to determine the etiology of vitamin B12 deficiency. When a patient swallows a pill, and 24 hours later the patients urine is negative for this vitamin, this may suggest a lack of intrinsic factor, which can be verified with an oral dose of IF(intrinsic factor) and radioactive vitamin B12.

Front 78

Night blindness and dry skin may suggest a deficiency of vitamin A. True/False

Back 78

True.
Bending of bones in children-Vit. D deficiency
Hypoprothrombinemia- Vit. K. deficiency
Increased fragility of RBCs- Vit. E. deficiency

Front 79

What is Celiac disease due to?

Back 79

It is caused by the toxic effects of gluten, a protein constitiuent of wheat flour, which changes the architecture of the small intestinal mucosa. In susceptible people the villi are lost and the surface epithelium are immature. This leads to loss of absorptive surface and deficiency of mucosal enzymes.

Front 80

Can Achalasia be a secondary effect of Chagas disease?

Back 80

Yes.

Front 81

A 20 year old is showing signs of unusual behavior and dysarthria> She has an increased level of Ceruloplasmin. She was diagnosed with Wilson's disease.

Back 81

Ceruloplasmin is the end product of copper that is incorporated into the liver and into the apoceruloplasmin.
Ceruloplasmin is elevated in wilson's disease because the transport of copper from the liver into bile is diminished leading to copper or rather excess ceruloplasmin.

Front 82

What is Zenker's diverticulum/

Back 82

It is a form of outpouching that results from a defect in the muscular wall of the hypopharynx in a natural area of weakness known as Killian's hiatus, which is formed by the oblique fibers of the inferior pharyngeal constrictor muscle and the cricopharyngeal sphincter.

Front 83

A 40 year old alcoholic presents with foul smelling stool and epigastric pain that extends to the back and is relieved by sitting upright or leaning forward. He has some pallor. He has normal lipase with elevated glucose. Why is the glucose elevated/

Back 83

Glucose intolerqnce occurs frequently in chronic pancreatitis, which is often due to a decrease in pancreatic reserve or in insulin responsiveness,

Front 84

A youn man goes to his physician for impotence. he also has galctorrhea. he is diagnosed with a prolactinoma. what medication is used for treatment?

Back 84

Bromocriptine. It is a dopamine agonist. this enhances the action of dopamine on the anterior pituitary, which results in a suppression of prolactin secretion.

Front 85

An elderly man goes to his doctor complaining of straining to urinate. He has a benign prostatic hypertrophy. What medications will the doctor likely prescribe?

Back 85

5 alpha reductase inhibitors. They block the activation of testosterone to dihydrotestosterone in the prostate.

Front 86

Which other hormones have similar structures to GH?

Back 86

prolactin and human placental lactogen.

Front 87

Why is Propylthiouracil best prescribed for hyperthyroidism?

Back 87

It inhibits the peroxidase enzyme.

Front 88

What would the TSH be in Grave's disease?

Back 88

Decreased TSH
Increased T3
Increased T4

Front 89

A patient with poorly controlled Atrial fib is about to start a regimen of Amiodarone for rhythm control. What tests should be ordered before this medication is administered?

Back 89

Pulmonary, Liver and Thyroid function tests

Front 90

Acth is high in Cushing's disease. True/False

Back 90

True. It is low in Cushing's syndrome.
Cushing's syndrome results from either administration of Glucocorticoids, or not as likely, bilateral hyperplasia of the adrenal gland.

Front 91

What medication can be employed to treat Cushing's disease?

Back 91

Ketoconazole. It inhibits steroid hormone synthesis.

Front 92

What is Conn's syndrome?

Back 92

It is hyperaldosteronism. This results in:
Increased sodium reabsorption, which augments the ECF hypertension
Increased potassium secretion
Increased H+ secretion
Increased ECF and blood pressure. This leads to inhibition of renin secretion.

Front 93

Which enzyme is likely responsible for an 8 year old boy going into premature puberty?

Back 93

21 Beta hydroxylase deiciency. without this enzyme there is an excess secretion of aldosterone and sex hormones, but no production of cortisol and estradiol.

Front 94

A 16 year old woman comes to the ED with syncope. The patient is found tobe hypertensive and has no axillary hair. The syncope is found to be secondary to her hypoglycemia.She is also hypokalemic, and has metabolic alkalosis. What enzyme deficiency is likely responsible for these signs?

Back 94

17 alpha hydroxylase deficiency. The lack of hair is due to the absence of androgens. The hypoglycemia is from the decreased glucocorticoids. The metabolic alkalosis, hypokalemia, and hypertension are all a result of the increased aldosterone.

Front 95

During a pancreatic study, a researcher injects CCK into onr of his patients. What hormone from the pancreas will be found at a higher level post injection?

Back 95

Glucagon.

Front 96

A young girl is found unconscious in her room. EMT technicians find that she has a glucose of 30. She is given infusional glucose as she is taken to the hospital. She has very high insulin levels, but very low protein C levels. What is likely causing this episode?

Back 96

Exogenous injection of insulin. protein C is a marker for insulin production. If this were from an insulinoms, the protein C level would also be very high.

Front 97

A young man is poorl responsive. he is hypotensive and tachypneic. His breath has a fruity smell. he is severely hyperglycemic, with hyperkalemia and metabolic acidosis. What is going on?

Back 97

The patient has diabetic ketoacidosis from uncontrolled diabetes mellitus.Hyperglycemia-insulin deficiency
Hypotension- ECF volume contraction resulting from high filtered load of glucose exceeds the kidneys reabsorptive capacity.
Metabolic acidosis, secondary from the excess production of ketoacids.
Hyperkalemia- lack of insulin
Insulin promotes K+ reabsorption.

Front 98

If one wanted to study the hormones involved in ovulation, during what day of the menses would the researcher have to study in order to investigate the day of ovulation?

Back 98

14 days before menses.

Front 99

Which hormones would be involved after a loss of GnRH in a female?

Back 99

LH
FSH

Front 100

A 29 year old female is studying her ovulation cycle by measuring her body temperature. After ovulation, her body temperature starts to rise. Which hormone is responsible?

Back 100

Progesterone.It affects the hypothalamic thermoregulatory center.

Front 101

During menses, the endometrium tends to slough off. Which 2 hormones have a role in this mechanism?

Back 101

The lack of estradiol and progesterone.

Front 102

A 5 year old boy is brought to his pediatrician. His parents believe that he is considerably smaller than his schoolmates. The parents are average in height. What blood tests might rule out an endocrine cause of his short stature?

Back 102

GH and Insulin like growth factor(IGF).
TSH and T4.

Front 103

A 24 year old pregnant women with hypothyroidism asks her doctor if levothyroxine is safe to take during the course of her pregnancy. What will the doctor say?

Back 103

It is safe and in fact essential to continue this medication. Thyroid hormones are very important for normal nervous system development.

Front 104

How are steroid hormone levels affected in liver disease?

Back 104

The liver metabolizes many steroid hormones. In liver disease, the steroid levels tend to increase due to the rate of reduced hepatic metabolism.

Front 105

A 10 year old boy is seen by his doctor, because he has recently undergone many changes that strongly resemble the signs of puberty. What potential problems along the line of the hypothalamic pituitary-adrenal-gonadal axis could be explained?

Back 105

Hypothalamus- excess GnRH
Pituitary-Excess FSH and LH
Testes-excess testosterone
Adrenal glands- excess steroid hormones
Excess steroid hormones are generally due to a hormone secreting tumor in the involved organ.

Front 106

Considering the above example, what adrenal enzymes may result in similar symptoms?

Back 106

21-Hydroxylase dieiciency, which are common causes of congenital adrenal hyperplasia(CAH). This is demonstrated by deficient cortisol and/or aldosterone and an excess of sex hormones. These deficiencies result in excessive steroid hormone precursors, which then enter into the androgen pathway and lead to excess sex hormones.

Front 107

Describe the weight and serum glucose changes in an insulinoma and a glucagonoma.

Back 107

Insulinoma-weight gain, hypoglycemia
Glucagonoma-weight loss, and hyperglycemia.

Front 108

A pregannt 29 year old woman in her third trimester has not felt any fetal movement over the last couple of days. What hormone can be measured to determine the health of the fetus?

Back 108

Serum or urinary estriol. Estriol is made by the placenta from dehydroepiandrosterone-S(DHEA-S) which is made by fetal adrenal glands.

Front 109

An elderly man complains of muscle twitches, with numbness and a tingling sensation around his mouth. He lost his wife about 9 months prior, and his diet has been quite off. He doesn't even go out much. What would be an apprpriate lab test?

Back 109

Serum Ca+ and Vit. D levels, may help establish a diagnosis of hypocalcemia. Poor diet= poor calcium intake coupled with minimal Vit. D levels due to little sun exposure. Muscle cramps , tetany and seizures with osteoporosis are copossible findings.

Front 110

A 73 year old woman with hypertension tells her doctor that she has been experiencing abdominal discomfort, constipation, heartburn and joint pain. She takes hydrochlorothiazide and TUMS. Hoe might one explain these symptoms?

Back 110

Hypercalcemia which is secondary to thiazide and antacid (calcium carbonate)use. Hypercalcemia symptoms include, posible calcium oxylate kidney stones, osteoporosis or pseudogout, constipation, peptic ulcer disease, depression with possible altered consciousness.
Her PTH is likely decreased
Calcitriol-decreased
Calcitonin increased, respectively.

Front 111

A 3 year old female known with a deletion of phenylalanine at the position F508 presents with a 14 day history of, foul smelling, large and fatty stools, with difficulty gaining weight. What is possibly the underlining cause of her malabsorption?

Back 111

Most patients with cystic fibrosis have a pancreratic insufficiency that results in thickened mucus in the pancreatic ducts, which causes obstruction and eventual autodigestion of the pancreas by activated enzymes.