Case History:

It is 2 am on June 23rd, your first night on call, and you are paged to see a cross cover patient who is complaining of shortness of breath. The patient is a 65-year-old male who had been admitted earlier in the day with a diagnosis of a "COPD exacerbation." The patient reports no improvement since admission in spite of standard management including bronchodilators, corticosteroids, and supplemental oxygen. He is now in obvious distress, using his accessory muscles, and unable to speak in complete sentences. Vitals reveal a BP = 180/110, RR = 32, HR = 128, and T = 36 8 . Notable physical findings include neck veins which fill to the angle of the jaw during expiration and collapse on inspiration, poor air exchange with prolonged expiration, wheezing, distant heart sounds, and obvious diaphoresis. Pulse oximeter reveals an oxygen saturation of 93%.

You rapidly assess the patient as being in respiratory failure and order continuous nebulized albuterol/ipratropium, a CXR, ABG, and ECG, and ask for respiratory therapy and anesthesia to be paged for assistance with an urgent intubation.

Case References:

Mechanical Ventilation Principles

• Mechanical Ventilatory Support. Harrison 's Textbook of Medicine. 15 th Edition. New York : McGraw Hill, 2001, pp 1526-1531.
• Mechanical Ventilatory Support, in Harrison 's On-Line:
  http://harrisons.accessmedicine.com/server-java/Arknoid/amed/harrisons/co_chapters/ch266/ch266_p01.html
• Tobin MJ: Mechanical ventilation. N Engl J Med 1994:330:1056-60.
• http://www.lumen.luc.edu/lumen/MedEd/medicine/pulmonar/lecture/vent/case_f.htm
  • A nice PowerPoint presentation available on LUMEN summarizing many aspects of mechanical ventilation.

Weaning

• Yang KL, Tobin MJ: A prospective study of indexes predicting the outcome of trials of weaning from mechanical ventilation. N Engl J Med 1991:324:1445-50.
• Esteban A, Frutos F, Tobin MJ, Alia I, Solsona J, Valverde I, Fernandez R, DeLaCal MA, Benito S, Tomas R, Carriedo D, Macias S, Blanc J: A comparison of four methods of weaning patients from mechanical ventilation. N Engl J Med 1995:332:345-50.

CPAP/BiPAP

• Keenan SP, et al. Which patients with acute exacerbation of chronic obstructive pulmonary disease benefit from noninvasive positive-pressure ventilation? A systematic review of the literature. Annals of Int Med 2003; 138(11); 861-871. http://www.annals.org/issues/v138n11/pdf/200306030-00007.pdf
  • A meta-analysis describing the benefit of CPAP/BiPAP in exacerbations of COPD.
• Esteban A, et al. Noninvasive Positive-Pressure Ventilation for Respiratory Failure after Extubation. NEJM 2004;350:2452-60.
• F/U editorial by Truwit JD and Bernard GR. Noninvasive Ventilation – Don't Push Too Hard. NEJM 2004;350:2512-15.

Mechanical Ventilation in Specific Disease States

• UpToDate ® has very nice succinct summaries of treatment strategies for Non-Cardiogenic Pulmonary Edema (i.e. ARDS), Cardiogenic Pulmonary Edema, and Status Asthmaticus.