Case 3

A 76-year-old man presents to the ED with increasing shortness of breath which has worsened over the preceding 24 hours. He is known to have chronic obstructive pulmonary disease (COPD).

Which of the following historical factors would make a diagnosis of infective exacerbation of COPD more likely?

On further questioning, he has had a productive cough with green sputum and intermittent fever over the last 2-3 days. He has no chest pain. He has had similar presentations in the past and is a persistent smoker.

Which one of the following examination findings would you least expect to find in this patient?

On examination he has: P = 110, RR = 26, BP = 160/95, peripheral cyanosis, normal heart sounds, bilateral coarse expiratory crackles and wheeze, and a temperature of 38.5^oC. His SaO₂ on air by pulse oximetry is 90%. You decide to administer controlled supplemental oxygen therapy (40%) and his SaO₂ increases to 95%.

Arterial blood gas analysis on supplemental oxygen reveals the following:

• pH = 7.30

• pCO₂ = 8.6 kPa
• pO₂ = 9.4 kPa
• HCO3^- = 30mmol/l
• BE = 5
• Lactate = 2.4 mmol/l

This ABG profile is consistent with his clinical presentation: True or False?