MEDICINE

GENERAL MEDICINE

Differential Diagnoses

Dyspnea Pulmonary causes Asthma COPD Pneumonia Pneumothorax Idiopathic pulmonary fibrosis PTE Upper airway obstruction Pleural effusion Cardiovascular causes Ischemia CHF Valvular disease Cardiomyopathy Hypertension Arrhythmias Pericarditis Metabolic acidosis Anemia Anxiety	Hemoptysis (rule out hematemesis and pulmonary edema) Lung cancer Infection (bacterial, fungal) Arteriovenous malformations PTE Vasculitis (Wegener’s, Goodpasture’s) Bronchiolitis/bronchiectasis Mitral valve stenosis Trauma Coagulopathies Drugs	Generalized Edema Congestive heart failure Renal causes (nephrotic syndrome, glomerulopathies) Cirrhosis Inflammation Malnutrition GI / protein losing enteropathies
Localized Edema Lymphatic obstruction Venous insufficiency / deep venous thrombosis Infection / inflammation	Exudative pleural effusions Bacterial pneumonias Metastatic disease PTE Tuberculosis Mesotheliomas	Transudative pleural effusions <Rx with diuretics> Congestive heart failure Cirrhosis Nephrotic syndrome PTE
Nausea V = Vestibular causes O = Obstruction M = Motility problems (opiates), metabolic problems I = Infection / inflammation T = Toxins

Treatment of Hyperkalemia

1. Repeat potassium level to rule out lab error.

2. Obtain EKG to look for peaked T waves, flattened P waves, AV block, and ventricular arrhythmias.

3. Stop any IV or PO potassium intake.

4. Start continuous EKG monitoring.

5. In the case of hyperkalemia with EKG changes, give calcium gluconate (10%) 5-10 mL IV over 3 minutes to stabilize the myocardium. Depending on severity, additional measures may be necessary:

a. Glucose, 50 g IV bolus, or infusion of 500 mL of 10% dextrose, plus 10 units of regular insulin IV.

b. NaHCO₃, 1 amp over 5 minutes.

c. Kayexalate, 20-50 g plus 100-200 mL or 20% sorbitol, given PO or NG.

d. Lasix, 40-160 mg IV over 30 minutes.

e. Dialysis.

6. Check electrolytes and pH. Correct electrolyte abnormalities and acidosis if present.

7. Identify and treat underlying cause of hyperkalemia (renal failure, potassium-sparing diuretics, exogenous potassium administration).

Hypokalemia

1. Before giving potassium, make sure that the patient can urinate!

2. For every 10 mEq KCl given, expect an increase in serum K⁺ of 0.1 mEq/L (except in renal failure).

3. Patients with heart failure should have K⁺ maintained > 4.0, as K⁺ is a good antiarrhythmic.

Hypocalcemia

1. Check Albumin

2. If Albumin is low (<4), then actual Ca⁺⁺= Correction Factor + Measured Ca⁺⁺

Ø Correction Factor = (4 – measured Albumin) * 0.8

3. Can treat with oral CaGluconate

Diabetic Ketoacidosis (DKA)

DKA is a potentially life-threatening complication of diabetes, usually seen in Type I (IDDM) diabetics. DKA is usually the result of an infectious process, but it can also occur due to poor compliance with insulin or after acute medical illness. Symptoms include nausea and vomiting, polyuria, polydispia, abdominal pain, malaise, and altered mental status.

Work-up

1. Serum glucose level (usually > 300 mg/dL).

2. ABGs (usually a pH < 7.3, and Pa_CO2 < 40 mmHg).

3. Serum electrolytes (HCO₃ < 15 mEq/L, decreased sodium (pseudohyponatremia secondary to hyperglycemia), increased anion gap, decreased total body K⁺ (initial K⁺ may be low, normal, or high)).

4. CBC & differential, U/A, urine and blood cultures, and CXR to rule out an infectious cause.

5. Calcium, magnesium, and phosphate (may be depressed, and will drop further with correction of DKA).

6. BUN and creatinine (typically show dehydration).

7. Amylase and LFTs (in a patient complaining of abdominal pain).

Treatment

1. Patients in DKA should be admitted to the ICU for close monitoring.

2. Replace fluids with normal saline until the glucose level is below 300 mg/dL, then switch to D₅W to avoid hypoglycemia. Fluid replacement strategies vary between residents; a common method is to replace 1/3 of the total deficit in the first 8 hours, 1/3 in the next 16 hours, and then the last 1/3 over the next 24 hours, in addition to maintenance fluids.

3. Administer regular insulin as an initial IV bolus of 0.15-0.2 U/kg, followed by a constant infusion at 0.1 U/kg/hr. Monitor serum glucose hourly for the first few hours, and then q2-4 hours. You would like to see the serum glucose decrease by about 80 mg/dL/hr.

4. When the serum glucose reaches 250 mg/dL, the insulin infusion rate should be slowed to around 2-3 U/hr until the HCO₃ level is close to normal and the urinalysis is free of ketones. Around an hour before stopping the infusion, administer an appropriate dose of subcutaneous insulin to cover the patient when the infusion stops. Restart the patient on sliding scale insulin when they are able to eat.

5. Serum potassium levels in patients with DKA may be low, normal or high. Do not replace the patient’s potassium until the patient’s DKA has resolved and you have rechecked the patient’s potassium.

6. Phosphate should only be replaced when the serum phosphate is less than 1.5 mEq/L. In this case, you should give 2.5 mg/kg of elemental phosphate intravenously over 6 hours.

7. Mg replacement is only needed in cases of significant hypomagnesemia or refractory hypokalemia.

8. Bicarbonate replacement is contraindicated because it can result in cerebral edema.