Thoracotomy increases peripheral airway tone and reactivity

Area of Science:

• Pulmonary Physiology
• Thoracic Surgery
• Respiratory Medicine

Background:

• Thoracotomy is a surgical procedure involving chest incision.
• Chronic instrumentation may affect lung function.
• Peripheral airway changes after thoracic surgery are not well understood.

Purpose of the Study:

• To determine if thoracotomy for chronic vascular instrumentation alters peripheral airway tone and reactivity.
• To compare changes in the left versus the right lung.
• To assess the impact on airway responses to various stimuli.

Main Methods:

• Utilized the wedged bronchoscope technique to measure peripheral airway resistance (RP).
• Studied anesthetized, ventilated dogs before and after left thoracotomy for instrumentation.
• Mapped airways to measure RP in identical sublobar regions of both lungs pre- and post-surgery.

Main Results:

• Baseline RP significantly increased in the left lung post-thoracotomy, but not in the right.
• Peripheral airway responses to acetylcholine, histamine, hypocapnia, and dry air challenges were heightened in the left lung.
• Total lung volume decreased similarly in both lungs, indicating no selective effect on overall lung size.

Conclusions:

• Left thoracotomy for chronic instrumentation selectively increases peripheral airway tone and reactivity in the ipsilateral (left) lung.
• The surgical procedure does not affect the contralateral (right) lung's airway function.
• These findings highlight localized pulmonary effects of thoracic surgery on airway dynamics.