Monday, January 11, 2016

A Boo

A 60 year old man with severe COPD on multiple inhalers and home oxygen presents with shortness of breath, productive cough, and increased work of breathing. In the emergency department, he has respiratory distress and is intubated. The resident sets a high minute ventilation in order to "blow off his CO2" since he is worried that the blood gas will be very acidemic. The patient then develops hypotension.

Challenge: Assuming this is not related to the patient's disease process, what is the cause of the hypotension?

Image shown under Creative Commons Attribution Share-Alike License, from Wikipedia.

1 comment:

Craig Chen said...

oops - when i named the case, i was thinking of "peek a boo".... "peep a boo" makes a lot less sense. oh well!
-
A Boo

This is a case of auto-PEEP, also called intrinsic PEEP. This occurs when there is incomplete expiration prior to initiation of the next breath. Progressive air trapping (dynamic hyperinflation) leads to increased alveolar pressure at end expiration. The increased intrathoracic pressure decreases venous return and reduces cardiac output. In this case, auto-PEEP is a result of expiratory flow limitation from the patient’s COPD.

Source: UpToDate.