Chronic Obstructive Pulmonary Disease (COPD) is characterized by obstructed airflow, making breathing difficult. When surgery is necessary for an individual with COPD, it introduces unique risks due to the body’s impaired ability to manage the stress of an operation and anesthesia. While COPD increases the chance of complications, proper pre-surgical preparation and meticulous perioperative management often make surgery a safe option. Safety is highly dependent on the severity of the lung disease and the nature of the planned surgical procedure.
Evaluating the Risk
The safety of surgery for a patient with COPD is determined through a detailed assessment of their baseline lung function and the invasiveness of the procedure. COPD significantly elevates the risk of Post-operative Pulmonary Complications (PPCs), which include pneumonia, acute exacerbation of COPD, and respiratory failure requiring mechanical support. Patients with COPD have an increased risk of all-cause mortality in the year following a major surgical procedure.
The severity of the underlying COPD, often measured by spirometry, is a major factor in risk stratification. However, the type and location of the surgery are often more predictive of complications than lung function numbers alone. Procedures closest to the diaphragm, such as upper abdominal or thoracic surgeries, carry the highest risk, with upper abdominal surgeries posing up to a 20-fold increased risk of PPCs compared to other procedures.
The duration of the operation also correlates directly with complication rates; surgeries lasting more than four hours have a significantly higher rate of PPCs. Pre-operative testing, which may include spirometry or arterial blood gas analysis, helps the medical team establish a patient’s respiratory reserve and identify those most likely to need intensive post-operative care.
Optimization Before Surgery
The period leading up to surgery is focused on optimizing a patient’s respiratory health to minimize the potential for post-operative complications. For patients who smoke, cessation is the single most effective intervention, and patients are strongly advised to stop at least four to eight weeks before an elective procedure. Quitting smoking for at least eight weeks can nearly halve the risk of respiratory complications, as this timeframe allows for improved ciliary function and clearance of mucus. Even shorter periods of abstinence can reduce carbon monoxide levels in the blood, but longer cessation is necessary to improve lung function.
Pharmacological management involves optimizing the use of inhaled bronchodilators, such as long-acting beta-agonists (LABAs) or long-acting muscarinic antagonists (LAMAs), to achieve the best possible baseline lung function. If a patient is experiencing an active exacerbation or infection, the surgery should be postponed until the condition is treated with appropriate antibiotics or corticosteroids. Pulmonary rehabilitation is a beneficial non-pharmacological strategy that can improve exercise capacity and respiratory muscle strength before the operation.
Managing the Procedure
During the operation, the anesthesia and surgical team employ specific techniques to protect the patient’s lungs. When possible, regional or local anesthesia is preferred over general anesthesia, as it avoids the need for a breathing tube and mechanical ventilation, which reduces the incidence of PPCs. If general anesthesia is necessary, the team uses ventilation strategies designed to prevent air-trapping. This includes utilizing lower tidal volumes and a slower respiratory rate to allow more time for exhalation, minimizing pressure buildup in the lungs.
Careful fluid management is utilized, as excessive fluid can lead to pulmonary edema and worsen lung function. Studies suggest a restricted fluid infusion strategy may help reduce the risk of PPCs. The duration of the procedure is also managed, with surgical teams working efficiently to minimize operative time, as longer procedures are known to increase the risk of complications.
Preventing Post-Surgical Complications
Post-surgery, a vigilant approach to recovery is necessary to prevent respiratory complications. Effective pain management is paramount because adequate pain relief allows the patient to take deeper breaths and cough effectively to clear secretions. Early mobilization, which involves getting the patient out of bed and walking soon after the procedure, helps improve lung volumes and reduce the risk of blood clots.
Patients are often instructed to perform deep breathing exercises and utilize an incentive spirometer. While the evidence supporting incentive spirometry is mixed for the general surgical population, it shows potential for benefit in high-risk groups, such as those with COPD. Vigilant monitoring in the recovery unit is maintained to quickly identify early signs of respiratory distress. Patients with more severe COPD or those undergoing high-risk procedures may be managed in a high-dependency setting where arterial blood gases can be regularly monitored.