IM 2 Flashcards
(158 cards)
CF-5 65 yo f brought to ER by family for increasing confusion and lethargy ofr the past week. She was recently diagnosed with small cell cancer of the lung. She is not taking any medications. Her BP 136/82 P84 R14 and labored, afebrile. On examination, difficult to arouse and reacts only to painful stimuli. No motor deficits, DTR are dec symetrically. Remander of exam is normal, normal JVP no edema. Labs sNa 108 sK 3.8 BC 24 BUN 5 Cr 0.5 SOsm 220 and UOsm 400 CT of brain WNL. Dx? next step? complication of therapy?
Dx: Coma/Lethargy 2’ to severe hyponatremia -> SIADH
NS: Hypertonic Saline
Complication: Osmotic Cerebral Demyelination (central pontine myelinosis)
S Osm?
280-300
Most common electrolyte disturbance among hospitals?
Hyponatremia <135
Clinical manefestation of hyponatremia?
Related to osmotic water shift leading to cerebral edema:
lethargy confusion siezures and coma
HyperOsm Hyponatremia
More dangerous and related to solute that is confined to extracellular space: glucose/mannitol.
Drawing solutes out and leadint to “relative” HypOnatremia.
Glucose HyperOsm State:
For every 100mg/dL increase, 1.6 mmol/L decrease in serum sodium.
Pseudohyponatremia?
sNa and tonicity are normal.
High serum protien levels or high lipid levels interfered with the measurement of serum sodium level.
Check the measured and calculated sOsm
Kidney free water excretion capacity?
kidney capacity to excrete free water is 20L/d
difficult to overwelm the system in primary polydipsia
Hypotonic Hyponatremia signs/symptoms of water loss?
vomiting, diarrhea, sweating/ dry MM, dimished U output, flat neck veins.
Hypervolemic signs/symptoms?
edema, elevated JVP, CHF, Cirrhosis, Nephrotic syndrome
Euvolemic hyponatremai?
Most commonly caused by SIADH -inapproprieate secreation seen in Pulm Dz, CNS Dz, Pain, Post OP, Paraneoplatic.
ADH?
Diagnose SIADH
Urine?
Labs?
ADH is a neuropeptide that concentrates urine. Water retention.
Exclusion, Hypoosmolar but Euvolemic:
Uosm >150 (non dilute)
UNa >20 and normal adrenal and thyroid function.
Other labs: low BUN low Uric Acid
Treat SIADH
unless severe: water restriction
Severe: symptomatic
Hypertonic saline
U Osm what does it tell you?
Kidney capable of excreating free water normally?
Max Dilute: 150-200: Urine max concentrated
Free water excretion is impaired you have a UOSm of >200? What does that mean?
1) Hypothyroidism
2) Adrenal Insufficiency
(Thyroid H and Cortisol are permissive for free water excretion)
NOTE: Addison’s Dz patient lack aldosterone.
Symptoms of osmotic cerebral demylination
Quadraplegic, pseudobulbar palsies and “locked-in” syndrom, coma or death
correct sodium by 0.5-1mEq/hr
mineralcorticoid def will do what to K?
K will be low.
24 year old man develops siezures following and emergent slenectomy after a car accident. sNA 116 and is corrected to 120mEq/L over the next three hours with hypertonic saline. Which factors led to his hyponatremia?
STRESS:
Elevation of serum vasopressin
56 yo M presents to the doctor for the first time complaining of fatigue and weight loss. He has never had any health problems, but he smoked a pack of cigs a day for 35 years. He is a day laborer and currently homeless and living in a shelter. PE: low normal blood pressure, skin hyperpigmentation, and digital clubbing. Appears euvolemic. Blood tests are drawn and follow up in 1 week. Lab calls that night and informes you that the patients sNa is 126 sK 6.7 Cr WNL BCb Low. Cause of hyponatremia?
Adrenal Insufficiency
83 yo F comes to your office complaining of headache and mild confusion. PMH is remarkable only for HTN, controlled with hydroclorothiazides. Her examination and lab test show no signs of infection, but her sNa 119 and plasma Osm 245 mOsm/kg she appears hypovolemic. Best initial therapy?
Infusion of normal saline.
Hypovolemic hyponatremia secondary to diuretic use.
58 yo man has undergone a lenghty colon cancer surgery. On the first day post op, he is noted to have significant hyponatremia with a Na 128. You suspect hyponatremia is due to intravenous infusion of hypotonic solution. Which of the following lab findings support your dx? uNa will be? uOsm? sOsm? sK?
1) kidneys excrete water retain Na: uNa low uOsm low 2) Excess water: sOsm low, low electrolytes -low K
CF-6 42 yo M in ER after sudden onset severe retrosternal chest pain that began an hour ago while he was at home mowing his lawn. He describes the pain as sharp, constant, unrelated to movement. It was not relieved by three doses of sublingual nitroglycerin administered by the paramedics while en route to the hospital. He has never ad symptoms like this before. His only medical history is hypertension, for which he takes enalapril. There is no cardiac dz in his family. He does not smoke, drink alcohol, or use illicit drug. He is a bball coach and very active. PE: tall long arms and legs, appears comfortable and diaphoretic; lying on the stretcher with eyes closed. afebrile P118 BP156/100RA 188/94LA chest: BCTA with pectus excavatum. HR tachy/regular with soft early diastolic murmur at right sternal border. Abd is benign and neuro is nonfocal. Xray show widened mediastinum. Dx? NS?
Aortic Dissection,
NS: control his BP
(IV-BB and perform noninvasive imaging, TEE, CT angio or MRI.)
Abdomial Aortic Aneurysm definition:
Dilation of >1.5 normal diameter of aorta. (nl: 1.5cm)
Most are abdominal below the renal arteries.
Aortic Dissection definition:
Tear or ulceration of aortic intima that allows pulsatile aortic flow to dissect longitudinally along elastic planes of media, creating false lumen or channel for blood flow. Sometimes reffered to as a dissecting aneurysm, although term is misleading because the dissection typically produces aneurysma dilation rather than the reverse.