Subinternship Medicine · Year 4 · from Subinternship Medicine

Case 3: Diabetic Ketoacidosis Requiring Prioritization Skills

Clinical Presentation

Patient Demographics: 28-year-old male

Chief Complaint: "I've been vomiting for 2 days and feel terrible"

History of Present Illness: Mr. Williams is a 28-year-old male with type 1 diabetes mellitus who presents with 2 days of nausea, vomiting, abdominal pain, and generalized weakness. He reports that he ran out of insulin 3 days ago and could not afford to refill his prescription. He has had polyuria and polydipsia for the past week with a 5-pound unintentional weight loss. He denies fever, cough, dysuria, or recent illness that may have precipitated his symptoms.

Past Medical History:

  • Type 1 diabetes mellitus (diagnosed age 12)
  • No other medical conditions

Medications:

  • Insulin glargine 24 units at bedtime (when available)
  • Insulin lispro sliding scale with meals

Social History:

  • Works part-time at a warehouse
  • Lost health insurance 2 months ago
  • Lives alone in an apartment
  • No tobacco, alcohol, or drug use

Physical Examination:

  • Vital Signs: Temperature 36.8C, HR 118 bpm, BP 98/62 mmHg, RR 28/min (Kussmaul respirations), SpO2 99% on room air
  • General: Ill-appearing, appears dehydrated, fruity odor on breath
  • HEENT: Dry mucous membranes, sunken eyes
  • Cardiovascular: Tachycardic, regular rhythm
  • Lungs: Clear to auscultation, deep rapid breathing
  • Abdomen: Diffuse mild tenderness, no rebound or guarding
  • Neurologic: Alert and oriented, no focal deficits
  • Skin: Poor turgor, dry

Inpatient Workup

Laboratory Studies:

  • Glucose 486 mg/dL
  • Sodium 128 mEq/L (corrected Na: 134 mEq/L)
  • Potassium 5.8 mEq/L
  • Chloride 94 mEq/L
  • Bicarbonate 8 mEq/L
  • BUN 38 mg/dL, Creatinine 1.9 mg/dL
  • Anion gap: 26
  • Serum ketones: Large
  • Beta-hydroxybutyrate: 6.2 mmol/L
  • pH 7.18, pCO2 18 mmHg
  • Lactate 2.4 mmol/L
  • WBC 14,200/uL
  • Hemoglobin 16.2 g/dL (hemoconcentration)

Diagnosis

Primary Diagnosis: Diabetic ketoacidosis (moderate severity)

  • pH 7.18 (moderate: 7.0-7.24)
  • Anion gap 26
  • Mental status intact

Precipitating Factor: Insulin non-adherence due to cost/access

Treatment Plan

Immediate Management (First 2 hours):

  1. Admit to step-down unit or ICU depending on institutional protocol
  2. IV access x 2 large bore
  3. Normal saline 1L bolus, then 500 mL/hr for first 4 hours
  4. Regular insulin IV infusion 0.1 units/kg/hr (no bolus needed with glucose < 500)
  5. Hold potassium replacement until K < 5.2 and urine output confirmed
  6. Monitor glucose hourly, BMP every 2-4 hours
  7. Search for precipitating infection (UA, CXR, blood cultures)

Ongoing Management:

  1. When glucose < 200, add D5 to fluids and reduce insulin to 0.02-0.05 units/kg/hr
  2. Transition to subcutaneous insulin when anion gap closes and patient eating
  3. Social work consult for insulin assistance programs
  4. Diabetes education before discharge

Sub-Intern Learning Points: This case emphasizes prioritization in the sub-intern role:

  1. Critical Task Recognition: DKA is a medical emergency requiring immediate intervention
  2. Time Management: This admission takes priority over non-urgent tasks
  3. Protocol Application: Following DKA protocol while individualizing care
  4. Anticipating Needs: Setting up frequent lab monitoring, calculating transition timing
  5. Patient Advocacy: Involving social work for medication access issues
  6. Documentation: Writing detailed admission note with clear assessment and plan

Clinical Image

Image Description: Fingerstick glucose testing demonstrating significantly elevated blood glucose, as seen in diabetic ketoacidosis.

Image Source: Wikimedia Commons - "Glucose test"

  • URL: https://commons.wikimedia.org/wiki/File:Glucose_test.JPG
  • License: Creative Commons Attribution-Share Alike 3.0
  • Author: David-i98

Discussion Questions

  1. Time Management: In Case 1, if you were simultaneously paged about a stable patient requesting sleep medication, how would you prioritize your tasks?
  1. Supervision Seeking: In Case 2, at what points in the patient's care would you absolutely need to staff with your senior resident or attending before acting?
  1. Autonomy Building: In Case 3, how might you demonstrate increasing independence over the course of managing the DKA, from initial presentation to discharge planning?
  1. Communication: How would you present Case 1 to your attending in a focused, efficient manner while ensuring all critical information is conveyed?
  1. Professional Development: What specific skills from these cases should you focus on improving before starting internship?

All cases for this lecture as Markdown