A thorough evaluation in the preoperative setting is essential to decreasing the intraoperative risk of anesthetic complications in adult CF patients. Assessment of the patient’s respiratory function is the top priority due to the progression of small-airway obstruction from air trapping and increased lung volumes. Pulmonary function test (PFT) provides essential information to the anesthesia provider evaluating the patient’s functional residual capacity, peak expiratory-flow rate, and vital capacity. If the results of one specific component of the PFT, the forced expiratory volume in one second (FEV-1), shows a value less than 10ml/kg, the patient may have chronic respiratory failure. This information will elucidate the severity of the disease and help the anesthesia provider make a patient-specific plan of care for ventilator settings and intraoperative crisis management.
The CF patient who presents for surgery with a cough, difficulty with respiration, activity intolerance, decreased baseline oxygen saturation, or current active infection needs to be pretreated to optimize pulmonary status before surgery. A sputum culture and sensitivity should be obtained. Additionally, allow sufficient time for the patient to complete a prescribed course of antibiotic therapy. This may be difficult because as CF patients grow into adulthood, they develop sensitivities to many antibiotics. Patients may require desensitization therapy for certain antibiotics before surgery to tolerate treatment or prevention. These interventions are time-consuming and demand planning.
Surgery should be scheduled for late in the day to allow the patient to fully maximize morning hours to mobilize pulmonary secretions. Also, the patient should be prepared for surgery at the beginning of the week. This will ensure the availability of proper support staff, such as physical therapists, dieticians, social workers, and pulmonary experts, for the postoperative period.
CF patients have a decreased ability to synthesize clotting factors due to the body’s reduced ability to absorb vital nutrients and vitamin K from the gastrointestinal tract. Pancreatic dysfunction in CF patients also contributes to this malabsorption, and these patients require pancreatic enzyme replacement in their diets. This decreased absorption may lead to a prolonged prothrombin time and partial thromboplastin time. Therefore, in addition to coagulation laboratory values, it is imperative to obtain a thorough history, particularly inquiring for increased bleeding, bruising, petechiae, and the presence of bloody sputum, to evaluate for any potential bleeding problems.
A preoperative review of the patient’s current medications assists the anesthesia provider in treating this patient population. Medications must be continued into the preoperative period, particularly considering cardiac medications, corticosteroids, and bronchodilators. The use of a steroid-stress dose preoperatively may benefit the patient.
During the preoperative period, the use of anxiolytics or sedatives is not beneficial. The risk of decreasing the patient’s respiratory drive is greater than the therapeutic benefit of antianxiety medications. Because of their sedating effects, antianxiety medications can eliminate or severely compromise the benefit of sputum clearance during the preoperative period.
The CF patient’s mucous can be highly viscous, which makes clearing the airways more difficult. The use of anticholinergic/antimuscarinic agents is contraindicated for routine use. If necessary, occasional anticholinergic/antimuscarinic agents should be limited to atropine because it has minimal antisaligogue effects compared to scopolamine and glycopyrrolate. An additional benefit of atropine is it increases bronchodilation compared to scopolamine and glycopyrrolate.
Preoperative use of osmotic laxatives can be beneficial to decrease opioid-induced constipation. Also, gastroesophageal reflux, shared in this patient population, should be pretreated with an H2 blocker and a promotility drug such as metoclopramide. Bicitra may be administered to increase the gastric pH, thus decreasing parenchymal pulmonary tissue damage should aspiration occur.
