Thoracic Spinal Versus Thoracic Epidural Anesthesia for Patients with Chronic Obstructive Pulmonary Disease Undergoing Supine Percutaneous Nephrolithotomy for Management of Renal Stones. a Prospective Double-blind Randomized Clinical Trial.

Owing to the elevated risk of perioperative comorbidities, chronic obstructive and restrictive pulmonary disorders can be a challenging task for the anesthetist. Endotracheal intubation and intermittent positive pressure ventilation (IPPV), two hallmarks of general anesthesia (GA), are known to increase the risk of serious complications such as barotrauma, laryngospasm, and bronchospasm. Patients who had neuraxial anesthesia had a lower rate of pulmonary and cardiac problems and deep venous thrombosis after surgery compared to those who received GA. Global Initiatives for Chronic Obstructive Lung Disease (GOLD) described COPD as a pulmonary disease with an inflammatory process that affects both the central and peripheral tracheobronchial tree, the pulmonary vasculature, and the pulmonary parenchyma. This persistent and cumulative process leads to the narrowing of the small airways, which is difficult to reverse, along with changes in the smooth muscle of the airway, increased secretion of mucus-secreting glands and goblet cells, and the development of perivascular pulmonary fibrosis. These changes contribute to the development of pulmonary hypertension and increase the workload on the right ventricle. Ultimately, COPD is characterized by the obstruction of airflow during expiration. When the small airway becomes inflamed, the condition is called "obstructive bronchiolitis," and when the lung tissue becomes destroyed, the condition is called "emphysema.". Impairment in ventilation and perfusion (V/Q) ratios and pulmonary mechanics come from air trapping and dynamic hyperinflation caused by obstruction in small airways.

Patients with COPD have a wide range of options for anesthesia, depending on illness stage, type of surgery, and length of operation. General anesthesia (GA) is known to increase the risk of problems for patients with COPD, especially when paired with endotracheal tube insertion and mechanical ventilation. Increased risk of hypoxemia and intra- and postoperative pulmonary complications; laryngospasm; bronchospasm; lung barotrauma; hemodynamic instability; hypercarbia; prolonged postoperative mechanical ventilation; and difficulty in weaning. To address these challenges, there has been a growing inclination towards employing various forms of regional anesthetic techniques whenever possible, including central neuraxial block. This approach aims to minimize the risks associated with general anesthesia and its potential complications, providing a safer alternative for COPD patients undergoing different types of surgical procedures. Regional blocking, as opposed to GA, has been found to improve pulmonary outcomes in patients with severe COPD and patients with normal lung function.