Selection of a surgical facility

Once a decision is made to perform surgery on a patient with obstructive sleep apnea, the surgeon must then select an operating room facility with personnel and equipment adequate for an elective and controlled management of the patient’s airway before and after the procedure. Unfortunately, the literature is insufficient to offer guidance regarding which patients can be safely managed as an outpatient as opposed to an inpatient basis or how long the patient should be monitored in the surgical facility .

Upper airway surgery in sleep apnea patients can temporarily worsen the sleep apnea and lead to serious and potentially fatal complications. Early detection of pending airway problems may prevent these complications. Although there are insufficient published data, it is assumed that patients with more severe sleep apnea are at greater risk for perioperative complications.

Surgical setting options may include use of an outpatient surgery center or a hospital operating room. Following the surgery in either location, the patient may be discharged to home after a short recovery room observation, observed for several hours in the recovery room, transferred to a 23- to 48-hour observation unit, transferred to the hospital by ambulance, admitted to a regular hospital room, admitted to a hospital room with telemetry, or admitted to some form of ICU. The decision about which surgical setting to use should be made with consideration of associated comorbidities, severity of apnea, sites of airway narrowing, type of anesthesia, length of anesthesia, need for postoperative narcotic agents, and type of surgery being performed. This determination is best made preoperatively . In a recent report of the American Society of Anesthesiologists , consultants were surveyed using a nonvalidated scoring system about opinions regarding outpatient surgery in patients with obstructive sleep apnea syndrome (OSAS). The consultant’s opinions suggested that a patient with mild sleep apnea undergoing uvulopalatopharyngoplasty (UPPP) or nasal surgery was not at increased risk for complications, whereas a patient with moderate sleep apnea undergoing UPPP was at increased risk of complications . The literature is confusing, however, because the term “outpatient” may be used to refer to a recovery room stay of less than 2 hours, a surgical stay less than 24 hours, or a surgical stay that does not go past midnight.

In theory, before discharging a patient after surgery, it should be known how well the patient can sleep in their usual way (typically flat in a normal bed, in their preferred sleeping position, and without supplemental oxygen or intravenous or intramuscular narcotic agents) and to know that their sleep apnea is not any worse than preoperatively. In reality, postoperative monitoring is never set up to simulate the home environment. Some monitoring situations tend to improve the sleep apnea (head of bed elevation, use of supplemental oxygen, use of steroids, frequent patient checks and alarms that disturb sleep and reduce deep sleep), whereas others tend to worsen the apnea (laying supine, receiving intravenous or intramuscular narcotics). Given the limitations that the monitored setting is not really like the home, the importance of the postoperative observation period is to document the presence or absence of sleep apnea and oxygen desaturation in the patient while sleeping without supplemental oxygen.

The need for postoperative monitoring depends on the procedure performed and associated comorbid conditions. The hospital policies and protocols and quality of the hospital nursing care also have an impact on the level and type of postoperative monitoring. For example, some facilities can perform continuous pulse oximetry in the extended recovery unit or regular nursing unit, whereas others require an ICU to administer this same level of care. It is this author’s opinion that most patients with mild or moderate sleep apnea undergoing nonairway surgery or nasal surgery only may safely be done as an outpatient, whereas those with severe sleep apnea may require some observation, preferably with some time asleep, before discharge. Most patients with mild obstructive sleep apnea hypopnea syndrome undergoing UPPP or other pharyngeal airway surgeries should at least be observed for several hours before discharge, whereas those with moderate or severe obstructive sleep apnea hypopnea syndrome should stay in some type of observation unit for a longer period of time, typically to include an observation of sleep.

Choice of anesthesia technique (local, general, or monitored anesthesia care)

The literature is insufficient to evaluate the effects of different anesthetic techniques on surgical complications after surgery in patients with OSAS. Because airway reconstructive surgery for sleep apnea causes blood to enter the airway, it is believed to be safest to perform these surgeries under general anesthesia, to control and protect the airway. When a patient with sleep apnea is undergoing nonairway surgery, local anesthesia or monitored anesthesia care is preferred. Sedation during a nonairway surgery must be performed carefully, to allow the patient to stay awake and maintain an adequate airway. With any sedation, oximetry and CO ₂ monitoring should be used. General anesthesia with a secure airway is preferred if the patient is going to require moderate or deep sedation.

Use of preoperative continuous positive airway pressure

Before any surgical procedure, the patient is often sleep deprived because of anxiety about the upcoming surgery. In addition, if the patient has poor continuous positive airway pressure (CPAP) compliance, sleep deprivation may persist . Once surgery is completed, however, the patient is more likely to enter delta and rapid eye movement sleep and may be predisposed to more severe sleep apnea . It is likely that any measures that can improve sleep quality before surgery might reduce the increase in deep sleep postoperatively. Although most patients who are undergoing upper airway surgery are doing so because they refuse or are poorly compliant with CPAP, even modest use of CPAP before surgery may be beneficial. Whenever possible, a patient should be asked to use CPAP for several weeks before and after surgery and to bring their machine into the hospital for perioperative use.

Use of narcotics and sedative agents

Use of sedative hypnotics, anxiolytic agents, and narcotics should be avoided before surgery in patients with OSAS. These agents have been reported to lead to sudden death, even in the preoperative holding area . Narcotics suppress respiratory drive, blunt the arousal response, and may lead to life-threatening hypoxemia. Benzodiazepine agonists effect upper airway dilator muscle tone and worsen sleep-disordered breathing . Flurazepam has been shown to increase the apnea index and triazolam reduces oxygen saturation and the arousal response, and increases the durations of respiratory events . If a sleep apnea patient requires sedation or an anxiolytic immediately before surgery, these patients should be given supplemental oxygen and monitored with continuous pulse oximetry.

Reflux and aspiration precautions

Obesity is common in patients with sleep-disordered breathing leading to increased intra-abdominal fat, intra-abdominal pressure, and higher incidence of hiatal hernia and an increased risk of gastroesophageal reflux . Obese patients tend to have a larger volume of gastric fluid, a lower gastric pH, and are at increased risk of aspiration during anesthesia induction or on extubation. To reduce these risks, obese patients should receive an H ₂ blocker, proton pump inhibitor, or esophageal motility stimulant before surgery . Following surgery, the stomach should be suctioned out.

Preoperative medical clearance

A consultation with the primary physician, cardiologist, anesthesiologist, or other appropriate specialists should be considered in patients with complicated comorbid conditions or multiple comorbidities. For example, a patient with hypertension requiring three antihypertensive agents or a patient with poorly controlled diabetes may benefit from a preoperative medical evaluation. The selection of an internist, cardiologist, or anesthesiologist for medical clearance should be based on availability and expertise of the consultant and the nature of the comorbid conditions. The purpose of the preoperative clearance is to optimize control of the comorbidities before surgery and to reduce the risk of surgical complications.

Patients with OSAS are at increased risk of hypertension because of an increased sympathetic drive . Because undiagnosed hypertension is common in the sleep apnea patient, blood pressure screening should be done before surgery in these patients. If blood pressure is elevated, these patients should be referred for treatment before surgery.

Communication with the anesthesia team

As the head of the surgical team, it is the responsibility of the surgeon to advise the anesthesia team about any potential difficulties that may arise during surgery. The anesthesiologist should be made aware about the presence and severity of the sleep apnea. Although it should be assumed that all OSAS patients may be more difficult to ventilate or intubate, there are some with macroglossia, retrognathia, or micrognathia who present a challenge to secure an airway. In these patients, the surgeon may request to have a difficult airway set or tracheostomy set in the operating room or to be ready to assist with a fiberoptic intubation.

Postoperative monitoring

Several studies have shown that the severity of the sleep apnea is typically unchanged or worse for the first 2 nights after UPPP . The first 24 hours after surgery are probably the most critical time for complications, although deaths from complications have occurred later, potentially from the accumulated effects of sleep deprivation, narcotic agents, and rapid eye movement rebound . Unfortunately, the literature is insufficient to offer guidance about how long monitoring is needed or if there is any real value from telemetry monitoring, ICU, or intermediate ICU monitoring units versus monitoring in a standard hospital room .

Postoperative monitoring is typically performed for early detection or prevention of complications. Continuous pulse oximetry is believed to be the easiest and most reliable method for early detection of postoperative hypoventilation because it can alert the nursing staff and physician of a pending airway complication. Continuous pulse oximetry with an audible alarm that can be heard by the nursing staff should be used for all OSAS patients following nonairway or upper airway surgery. Intermittent checks of oxygen saturation typically have no benefit because the patient usually is awakened by putting on the oximetry probe. Although there is no consensus about whether electrocardiographic monitoring affords any protection to the patient with sleep apnea, it should be considered in those with significant cardiac disease or arrhythmias.

ICU monitoring has been suggested to try to decrease the risk of complications after OSAS surgery . Most older publications have recommended the ICU to monitor oxygen saturation and cardiac arrhythmias , whereas others have advocated ICU monitoring because of the high reported incidence of serious airway complications (13%–25%) following UPPP . Newer publications have noted a much lower risk of airway complications (1.4%), likely caused by more aggressive perioperative treatment of tissue edema and avoidance of excessive sedation . Except for the sickest of sleep apnea patients, ICU monitoring is rarely required.

Most surgeons, anesthesiologists, and hospitals have standard protocols governing their preoperative and postoperative standard of care and orders for surgery . Institution and anesthesia protocols should be examined to ensure that routine recovery room, surgical ward, or extended recovery unit orders are appropriate for sleep apnea patients ( Boxes 1 and 2 ). In general, monitoring of vital signs for the sleep apnea patient should be more frequent. Nursing checks should specifically monitor for respiratory rate, depth of breathing, presence of snoring, and to verify that there is no apnea, hypopnea, or labored breathing.

Patient positioning

The apnea-hypopnea index and hypoxemia tend to improve when sleep apnea patients sleep in the lateral or prone position, or with the head of bed elevated. Sleep apnea is usually worse when supine, because of posterior collapse of the base of tongue. Following surgery, elevation of the head of the bed reduces soft tissue edema, turbinate swelling, and typically improves the nasal airway. Because there are no valves in the veins of the head and neck, lying flat increases venous pressure and worsens tissue edema. Although the literature is insufficient to provide definitive guidance in the postoperative period, most physicians agree that after airway surgery, the head of bed should be elevated and the supine position should be avoided .

Postoperative analgesia

All opiates including morphine, meperidine, hydromorphone, and fentanyl lead to a dose-dependent reduction of respiratory drive, respiratory rate, and tidal volume, which can cause hypoventilation, hypoxemia, and hypercarbia . These agents are of particular concern in the patient with sleep apnea because the frequency and severity of the respiratory events worsen after administration. This poses a dilemma for these patients because upper airway reconstructive surgeries are often quite painful and typically require narcotic agents for 10 to 14 days for adequate pain control . It has been assumed that the stronger narcotic agents, which are administered through intramuscular or intravenous routes, cause more respiratory suppression that those given by an oral route. Nonetheless, the literature is insufficient to evaluate the effects of different analgesic techniques and there is no agreement about the safety of nurse-administered versus patient-controlled analgesia with systemic opioids .

In general, narcotic agents should be titrated for pain severity and used only when nonnarcotic agents are ineffective. Stronger narcotic agents should be used only when weaker analgesic agents are not adequate. Mild to moderate pain can be treated with oral opioid agents, such as codeine, hydrocodone, oxycodone, and propoxyphene, because these agents have only mild effects on the respiratory system. Nonnarcotic options include acetaminophen or the centrally acting agents, such as tramadol hydrochloride. Nonsteroidal anti-inflammatory agents (ibuprophen, naproxen, ketorolac tromethamine) or the cyclooxygenase-2 agents (celecoxib) may also be helpful but should be used with caution because of the potential for increased bleeding. Topical anesthetics, such as benzocaine, are also useful supplements to control pain.

Use of continuous positive airway pressure and supplemental oxygen

Maintaining adequate oxygenation is important following any surgery. Oxygen desaturation can lead to cardiac arrhythmias or serious cardiac and neural complications. In patients without sleep apnea, supplemental oxygen is used following surgery to maintain the oxygen saturation above 90%. Typically, supplemental oxygen is discontinued when the patient is able to maintain their baseline waking oxygen saturation while breathing room air. In the sleep apnea patient, the goal is not just to normalize the waking oxygen saturation but also the sleeping oxygen saturation. CPAP can be safely used after most upper airway surgeries to prevent respiratory events and oxygen desaturation during sleep and should be used in all patients who were able to use it before surgery. Following surgery, CPAP may also reduce the risk of gastroesophageal reflux . Patients should be instructed to bring their own positive airway pressure machine to the surgery facility for postoperative use. The CPAP or BiPAP machine should be used during sleep at the preset pressure. The CPAP pressure may be changed if needed, either to a higher pressure in the presence of tissue edema or persistent desaturations during sleep, or a lower pressure following enlargement of the upper airway, or if the patient is unable to tolerate a higher pressure. Another option is an autoadjusting CPAP machine, which adjusts according to a preset paradigm based on the presence of respiratory events or airflow limitation. The only limitations of CPAP use are after maxillary advancement because of the potential of subcutaneous emphysema and after nasal surgery because of nasal congestion or bleeding. Following nasal surgery, however, CPAP can be used with a full face mask instead of a nasal mask or nasal pillows.

Reducing airway edema

Edema caused by upper airway surgery or a difficult intubation may cause airway compromise, especially in those with severe apnea, multiple sites of airway compromise, or those undergoing multiple airway surgeries. Tissue edema occurs in all surgeries, even after laser and radiofrequency procedures . Administration of systemic steroids is a reliable method of reducing edema in the upper airway . The preferred corticosteroid agent is dexamethasone (10–15 mg/dose in adults) because it has the lowest sodium retention of all of the steroid agents. For optimal effect, dexamethasone should be administered before surgery and several times postoperatively.

Soft tissue edema may be reduced by cooling of the tissue, either before incision or after surgery. Application of external ice packs or sucking on ice chips tends to reduce pain and swelling. Tissue precooling with ice has been shown to reduce edema in thermal wounds from lasers or cautery units. Topical or systemic antibiotic prophylaxis given within 1 hour of incision reduces the risk of infection in contaminated surgeries and has been shown to reduce pain after procedures, such as tonsillectomy. Antibiotics may also limit edema by reducing bacterial contamination of the surgical wound. For oropharyngeal transmucosal surgeries, preoperative and postoperative topical chlorhexidine rinses reduces bacterial counts in the oral cavity. Perioperative use of a broad-spectrum antibiotic agent with aneurobic coverage should be considered for sleep apnea patients undergoing any upper airway surgery.

Nasal obstruction and nasal packing may cause or worsen sleep apnea and improving the nasal airway can reduce the severity of sleep apnea . Following septoplasty, the best options are to use quilting septal sutures; septal splints; nasal tubes, such as Doyle splints; or nasopharyngeal airways sewn into place. Nasal packing should be avoided in patients undergoing nasal surgery. A decongestant nasal spray, such as oxymetazoline, or a systemic decongestant is also effective in reducing nasal obstruction following nasal surgery or nasal intubation.

Postoperative sedatives

Many patients complain of insomnia following surgery, and it has been a common practice to prescribe sedative hypnotics to help the patient sleep. Sedative hypnotics and anxiolytics should be avoided, however, because of their negative effects on arousal thresholds, apnea duration, apnea severity, and oxygen desaturation. If a sleep aid is necessary, short-acting nonbenzodiazepine hypnotic agents are considered safer than benzodiazepine hypnotics. Two nonbenzodiazepine hypnotic agents have been shown to have minimal effect on sleep apnea severity. Administration of zaleplon (half-life 1 hour) and zolpidem tartrate (half-life 2.5 hours) had no significant effect on the apnea-hypopnea index compared with placebo in mild to moderate sleep apnea patients . Zaleplon had no effect on the oxygen saturation, yet zolpidem reduced the lowest oxygen saturation and the total time with arterial oxygen saturation less than 90% and 80% .

Deep vein thrombosis prophylaxis

Obesity, advanced age, long surgical procedures, and prolonged bed rest predispose to deep vein thrombosis and pulmonary emboli. The risk of deep vein thrombosis can be reduced by application of sequential compression stockings, elastic stockings, or subcutaneous heparin. Deep vein thrombosis prophylaxis is indicated for most patients undergoing surgery for sleep apnea.

Blood pressure control

Hypertension is more common in OSAS patients and these patients are at increased risk of postoperative hypertension because of increased sympathetic tone . To maintain a postoperative systolic blood pressure below 160 mm Hg and diastolic below 90 mm Hg, over one half of the patients undergoing upper airway surgery for OSAS require treatment with an antihypertensive agent in the recovery room (S. Mickelson, unpublished data, 2006). Blood pressure control is most important after any osteotomies, because postoperative bleeding from bone is blood pressure dependent and bleeding cannot be controlled easily. Blood pressure control is important to reduce the risk of postoperative bleeding, hematoma, and secondary tissue edema.

Criteria for discharge

The literature is insufficient to offer guidance about the appropriate time for discharge of these patients. Consultants to the American Society of Anesthesiologists agreed that the room air oxygen saturation should return to its preoperative baseline, that patients should not be hypoxemic or develop airway obstruction when left undisturbed, and that these patients should be monitored for 7 hours after the last episode of airway obstruction or hypoxemia while breathing room air in a nonstimulating environment . Although these recommendations are commendable, they are not practical for many patients. Most patients with sleep apnea are undergoing surgery because they will not or cannot use CPAP. Because surgery is not successful in all patients, many continue to have apnea following surgery. A more practical recommendation is for respiratory events and hypoxemia to be no worse at discharge as compared with baseline (preoperative sleep study). There are certainly some patients with persistent sleep apnea who may need supplemental oxygen at home or who should be instructed to sleep with their head of bed elevated. Home measures to reduce edema may need to be continued.

Patients should not be discharged home until they can swallow adequately so that they can maintain hydration and adequate nutrition at home. Pain should be adequately controlled with oral analgesics. In addition, the patient’s vital signs (temperature, pulse, blood pressure, respiratory rate) should be stable before discharge.