Today for intern report, Dr. Nelson walked us through a case of an older gentleman with COPD, chronic back pain, and tobacco use who presented with progressive abdominal pain, bloody stools, and unintentional weight loss, found to have rectal adenocarcinoma. His hospital course was c/b hypoxia, which was the focus of our discussion.

pulse ox.png

Learning Points:

  1. Hypoxemia has a large ddx including:

    • Hypoventilation (CNS depression, obesity hypoventilation, impaired neural conduction, muscular weakness, poor chest wall elasticity)
    • V/Q mismatch (obstructive lung diseases, pulmonary vascular diseases, interstitial diseases)
    • Right-to-left shunt (anatomic shunts and physiologic shunts)
    • Diffusion limitation
  2. Always evaluate the patient at bedside to assess their vitals (is the pulse ox wave form accurate?), work of breathing/use of accessory muscles, cardiac and lung exams, etc.

  3. Our patient was worked up with an basic labs, ABG, CXR, CT angiography, which were all unrevealing. Ultimately, it was felt that his hypoxia was related to pain with increased splinting in the setting of underlying kyphosis and COPD. His hypoxia improved with pain control.