What type of adverse event may increase post-operative complications in recently abstinent smokers?

The correct answer is pneumonia because recently abstinent smokers are at an increased risk of respiratory complications following surgery. Smoking damages the respiratory system, affecting mucociliary function and increasing the likelihood of pulmonary infections. Upon quitting, the lungs begin to clear out accumulated toxins and debris, which can temporarily lead to increased susceptibility to infections such as pneumonia. This heightened risk is particularly relevant during the post-operative period when patients are already vulnerable due to anesthesia and potential immobility.

While dehydration, anemia, and diabetes can lead to complications in various clinical scenarios, they do not have the specific connection to post-operative respiratory issues that pneumonia does for recently abstinent smokers. Dehydration may be a concern in any surgical context, but it does not directly relate to the smoking status of the patient. Anemia might complicate recovery, but it is not directly influenced by the cessation of smoking in the same way. Diabetes is a chronic condition that can lead to complications but is not an immediate result of stopping smoking, nor is it specifically linked to increased post-operative pneumonia risk in this context.