Intern Report 8.13

internreport

Case Presentation by Lauren Kroll, MD

Chief complaint: “I can’t breathe.”

HISTORY OF PRESENT ILLNESS
This patient is a 49 year old female with a past medical history of alcohol abuse who presents to the Emergency Department as a medical code for difficulty in breathing. The patient states her difficulty in breathing started gradually last night, and that it is getting progressively worse. She has never experienced anything like this before. She denies fever, chills, cough, congestion, chest pain, and leg swelling. She does admit to some mild epigastric pain, which has been present for the past two days. The epigastric pain is accompanied by nausea and multiple episodes of non-bloody, non-bilious vomiting.

Past medical history: Hypothyroidism, seizure disorder, deep venous thrombosis (diagnosed in December 2014), alcoholism.
Past surgical history: None.
Medications: None (the patient does state she is supposed to be on both levothyroxine and coumadin).
Allergies: Dilantin, phenobarbital.
Social history: Significant for both tobacco and heavy alcohol abuse. No intravenous drug abuse.

PHYSICAL EXAM
Vitals: BP 119/84, HR 126, RR 38, T 35.4, SaO2 99% (room air)

General: Well developed African American female in respiratory distress.

HEENT: Normocephalic, atraumatic. No conjunctival pallor. No scleral icterus. Dry mucous membranes. No pharyngeal erythema. The patient’s breath has a fruity odor.

Cardiovascular: Tachycardic, regular rhythm. No murmurs. No jugular venous distention, no edema.

Respiratory: Tachypnic. Lungs clear to auscultation bilaterally, no wheezes or crackles. No accessory muscle use, no retractions.

Gastrointestinal: Abdomen soft, slightly tender to palpation in the epigastric area, and non-distended. No rebound tenderness, no guarding. Bowel sounds present.

Neurologic: Alert and oriented x 3. Strength equal in all four extremities.

Skin: Warm, dry.

DIAGNOSTIC STUDIES
EKG:
ecg kroll

Laboratory studies:

Basic metabolic panel: Na 137, K 4, Cl 98, HCO3 5, BUN 13, Cr 1.06, glucose 122

Complete blood count: WBC 15.7, Hb 14.2, Hct 43.5, platelets 338

Coagulation studies: PT 10.9, PTT 29.2, INR 1.03

Arterial blood gas: pH 6.879, pCO2 22.1, pO2 95, HCO3 4

Beta-hydroxybutyrate 77.5 (normal 0.2 – 2.8)

Troponin <0.017

NT-PRO BNP 162

Liver function tests: amylase 97, lipase 888, total bilirubin 0.4, direct bilirubin 0.1, ALT 21, AST 68, alkaline phosphatase 98, albumin 2.9

EtOH 151

Urinalysis: 2+ ketones, 2+ protein, specific gravity 1.010, otherwise unremarkable

Chest x-ray:
cxr kroll

Questions:
1.
The patient’s acid base status is best described as which of the following?
A) anion gap metabolic acidosis (with complete respiratory compensation)
B) non-anion gap metabolic acidosis (with complete respiratory compensation)
C) anion gap metabolic acidosis (with incomplete respiratory compensation)
D) non-anion gap metabolic acidosis (with incomplete respiratory compensation)

2. Initial Emergency Department fluid management for this patient should include which of the following?
A) 5% dextrose in normal saline + insulin
B) 5% dextrose in normal saline + thiamine
C) 5% dextrose in water + thiamine
D) 5% dextrose in water + 3 amps of NaHCO3

3. As the patient is treated in the Emergency Department, which of the following would be expected with repeat blood draws and urinalysis?
A) beta-hydroxybutyrate will decrease; urine ketones will decrease
B) beta-hydroxybutyrate will decrease; urine ketones will remain unchanged
C) beta-hydroxybutyrate will increase then decrease; urine ketones will decrease
D) beta-hydroxybutyrate will decrease; urine ketones will increase then decrease

Answers & Discussion
1) C
2) B
3) D

1. The patient’s acid base status is best described as which of the following?
A) anion gap metabolic acidosis (with complete respiratory compensation)
B) non-anion gap metabolic acidosis (with complete respiratory compensation)
C) anion gap metabolic acidosis (with incomplete respiratory compensation)
D) non-anion gap metabolic acidosis (with incomplete respiratory compensation)

1) In interpreting this patient’s arterial blood gas, we first look at the pH. pH is 6.879; this is an acidosis.

2) Next, in order to determine whether this is a metabolic or a respiratory acidosis, we look at the pCO2. pCO2 is 22.1 (low); therefore, this is a metabolic acidosis.

3) Next, we calculate the patient’s anion gap (anion gap = Na – Cl – HCO3). Anion gap is 34 (high); therefore, this is an anion gap metabolic acidosis. Don’t forget, the patient’s expected anion gap can be determined by multiplying her albumin by three; given her albumin of 2.9, we would expect her anion gap to be approximately 8.7.

4) Next, we can use Winter’s formula (expected pCO2 = 1.5(HCO3) + 8 +/-2) to determine whether or not the patient’s respiratory status is completely compensating for her metabolic derangements. This patient’s expected pCO2 is 15.5, but her actual pCO2 is 22.1; therefore, her respiratory compensation is incomplete.

This patient’s diagnosis is alcoholic ketoacidosis (AKA). Like patients with diabetic ketoacidosis (DKA), those with AKA often also present with nausea and vomiting, which leads to a concomitant metabolic alkalosis. Therefore, it is important to remember that, while the patient’s primary acid base disturbance is an anion gap metabolic acidosis, it is possible for their serum pH to be acidemic, normal, or even alkalemic.

2. Initial Emergency Department fluid management for this patient should include which of the following?
A) 5% dextrose in normal saline + insulin
B) 5% dextrose in normal saline + thiamine
C) 5% dextrose in water + thiamine
D) 5% dextrose in water + 3 amps of NaHCO3

Again, this patient’s diagnosis is alcoholic ketoacidosis (AKA). AKA most commonly occurs in patients who chronically abuse alcohol and abruptly stop drinking; malnutrition and dehydration lead to ketone body formation. Initial Emergency Department management of AKA should include 5% dextrose in normal saline with thiamine added (to prevent Wernicke-Korsakoff Syndrome).

Insulin, although it is an important component of the Emergency Department management of diabetic ketoacidosis (DKA), is contraindicated in the treatment of AKA. Most patients with AKA do not demonstrate hyperglycemia (this patient’s glucose is 122). A bicarbonate drip can be considered in patients with pH < 7.1 (this patient’s pH is 6.879), but is not usually necessary and would not be the first step in managing this patient.

3. As the patient is treated in the Emergency Department, which of the following would be expected with repeat blood draws and urinalysis?
A) beta-hydroxybutyrate will decrease; urine ketones will decrease
B) beta-hydroxybutyrate will decrease; urine ketones will remain unchanged
C) beta-hydroxybutyrate will increase then decrease; urine ketones will decrease
D) beta-hydroxybutyrate will decrease; urine ketones will increase then decrease

In the body, beta-hydroxybutyrate is metabolized to acetoacetate and acetone. Urine dipsticks detect only acetoacetate (not beta-hydroxybutyrate). In alcoholic ketoacidosis (AKA), the initial ratio of beta-hydroxybutyrate to acetoacetate is high. However, as the patient receives treatment, beta-hydroxybutyrate will be metabolized and its serum concentration will decrease. Because beta-hydroxybutyrate is metabolized to acetoacetate and acetone, urine concentrations of acetoacetate (and, thereby, urine ketones) will transiently increase, then decrease.

Teaching Pearls

  1. Suspect alcoholic ketoacidosis in a patient with a history of alcohol abuse who presents to the Emergency Department with an anion gap metabolic acidosis, ketonuria, elevated beta-hydroxybutyrate, and a normal blood glucose.
  1. In addition to an anion gap metabolic acidosis (the primary acid base disturbance in alcoholic ketoacidosis), patients often also present with nausea and vomiting, which leads to a concomitant metabolic alkalosis.
  1. Treatment of alcoholic ketoacidosis includes 5% dextrose in water, with thiamine added. A bicarbonate drip can be used in cases where the patient’s pH is less than 7.1.

 

References

Marx JA, Hockberger RS, Walls RM, et al. Rosen’s Emergency Medicine Concepts and Clinical Practice. 8th edition. 2014.

Rosh Review.

UpToDate. Fasting ketosis and alcoholic ketoacidosis. http://www.uptodate.com/contents/fasting-ketosis-and-alcoholic-ketoacidosis. Accessed January 2015.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: