Chairman Rounds Medicine I Jesse Lester, Kannan Samy, Matt Skomorowski, Dan Verrill

Patient Presentation 54 year old African American female presents to the ED with vomiting and depression on 12/3 Vitals: BP 103/62, HR 119, RR 20, T 98F Her symptoms began four days ago. What else would you like to ask her?

History of Present Illness Patient reports a recent increase in her alcohol intake and depressed mood. Her sister recently died and the patient is having difficulty coping with the loss. What things would you suspect knowing this information?

Past Medical History Non-insulin dependent diabetes mellitus Alcoholic Hepatitis Hypertension s/p C-section Medications: –ASA 81mg –Nexium 40 mg –Januvia 100mg –Diovan 80 mg –Magnesium Oxide 400mg BID

Social History Current smoker Patient reports occasional alcohol consumption. Daily alcohol use is approx. 1/4c gin. Not employed, single and lives alone

Review of Systems Patient denies fever, diarrhea, abdominal pain, ill contacts, change in bowel movements, problems with urination. Patient does report orthostatic weakness/dizziness, and feels she cannot eat and continues to vomit because of emotional upset. Whatever she puts in comes back up.

Physical Exam Gen: No acute distress, appears moderately ill, alert and oriented ENT: Neck is supple, no adenopathy, sclerae are non icteric Pulmonary: Unlabored respiration, good breath sounds bilaterally CV: RRR, no murmors, normal S1S2 Abd: soft, nontender, no organomegaly, normal bowel sounds Psych: Flat affect, poor eye contact

Labs CBC: WBC 2.4, HGB 11.1, HCT 31.9, MCV 116.5, Plt 81 BMP: Glucose 74, BUN 14, Creatinine 1.20, Na 138, K 3.8, Cl 97, HCO3 8, Ca 7.3 ABG: 7.12/21/98/7/95% Blood Osmolality 350 Ethanol: Lactate: 4.4

Labs, continued Urinalysis: Nitrite negative, leukocyte esterase trace, glucose negative Utox Panel: negative

Differential Diagnosis?

Step 1: Determine the primary insult 1)pH – acidosis or alkalosis? - normal 7.4 2) Metabolic or respiratory? - Normal bicarbonate=24 >24=alkalosis <24=acidosis -Normal pCO2=40 >40 acidosis <40 alkalosis Our patient: pH=7.12 pCO2=21 pO2=98 Bicarbonate=7 O2 sat=95%

Step 2: Compensation 1)Respiratory compensation for primary metabolic disorder Acidosis: Winter’s formula:1.5 * HCO /-2 = PCO2 (if compensated) Another method:1.2 *∆HCO3 +/-2 = ∆PCO2 (if compensated) Alkalosis:0.6 *∆HCO3 +/-2 = ∆PCO2 (if compensated) Our patient: 1.5 * (7) + 8 +/- 2 = Patient’s pCO2 = 21, therefore the metabolic acidosis is compensated

Step 2: Compensation 2) Metabolic compensation for primary respiratory disorder Acidosis: Acute:0.1 * ∆PCO2 +/- 2= ∆HCO3 Chronic:0.3 * ∆PCO2 +/- 2= ∆HCO3 Alkalosis: Acute:0.2 * ∆PCO2 +/- 2= ∆HCO3 Chronic:0.4 * ∆PCO2 +/- 2= ∆HCO3

Step 3: Anion Gap 2) Will be elevated if there is another serum anion creating the acid-base disturbance 1)Only applicable with metabolic acidosis Normal AG = Na - (Cl+HCO3) = 12 +/- 2 (or 6-12 depending on who you are asking) Our patient = 138 – (97+7) = 138 – 104 = 34 Therefore the patient has an elevated anion gap metabolic acidosis

Step 4: ∆/ ∆ Gap 2) Will be abnormal if a mixed disorder is present 1)Only applicable with an anion gap metabolic acidosis In a sole AG metabolic acidosis ∆AG = ∆HCO3 should hold true Our patient: ∆AG = 34 – 12 = 22 the predicted HCO3 = 24 – 22 (AG) = 2 Patient’s bicarb = 7, there is a base excess of 5 Therefore there is a coexisting metabolic alkalosis, possibly due to her nausea/vomiting or contraction alkalosis.

Step 5: Osmolal Gap 2) Will be abnormal if there is another electrolyte or ion present in serum 1) Calculated when there is an anion gap metabolic acidosis OG = 2 * Na + glucose/18 + BUN/2.8 The calculated number should be compared to the patient’s serum osmolality - if the gap is greater than 10 it is abnormal Our patient = / /2.8 = Serum osmolality (lab value) = 350 Therefore the patient has an elevated osmolal gap

Step 6: Urine Anion Gap 2) Will be abnormal if there is another electrolyte or ion present in serum 1) Can be used to differentiate between gastrointestinal or renal cause of metabolic acidosis UAG = (Na + K) – Cl The normal urinary anion gap is near zero or positive. A positive value indicates a renal insult, such that there is a problem with acidification of urine. A negative value indicates a gastrointestinal insult, such as the loss of bicarbonate in diarrhea.

Differential Diagnosis Differential for anion gap metabolic acidosis: –Methanol –Uremia –DKA –Paraldehyde –Infection, Iron, INH –Lactic Acidosis –Ethylene Glycol –Salicylates, Sepsis

Differential Diagnosis Differential Diagnosis for elevated osmolar gap: –Methanol –Ethylene Glycol –Ethanol –Isopropyl Alcohol What tests would you order to differentiate these conditions?

Calcium oxalate crystals

Differential Diagnosis Differential diagnosis for non-anion gap metabolic acidosis: –Diarrhea –Uremia –RTA –Addison’s Disease –Acetazolamide

Differential Diagnosis Differential diagnosis for metabolic alkalosis: –Vomiting –NG suction –Contraction alkalosis

Differential Diagnosis Differential diagnosis for respiratory acidosis: –Hypoventilation or other conditions that interfere with respiratory drive –Obstructive and restrictive lung disorders

Differential Diagnosis Differential diagnosis for respiratory alkalosis: –Hypoxia leading to hyperventilation –Primary hyperventilation