OSA Protocol Promotes Safer Care

R. Deutscher, MD; D. Bell, MD; S. Sharma, MD

To the Editor

Sleep apnea can be a complicating factor in the administration of anesthesia, and in the provision of pain relief perioperatively. This document is designed to outline an approach to the perioperative management of surgical patients diagnosed or suspected of having sleep apnea. Signs and symptoms of sleep apnea are outlined in Table 1.

Table 1. Clinical Features of Obstructive Sleep Apnea

Symptoms Signs
Nocturnal Events
Witnessed loud snoring and apnea Short sleep latency
Restless sleep with frequent movements Obesity (BMI >30)
Sudden awakenings with choking or shortness of breath Hypertension
Nocturnal awakenings and insomnia Upper airway abnormalities
Nocturnal enuresis or frequent nocturia Pulmonary hypertension, RV hypertrophy on ECG, cardiomegaly
Nocturnal sweating Polycythemia
Diurnal History
Excessive daytime sleepiness
Poor memory or concentration
Morning headaches
Morning dry throat

The recommendations in this document are not intended to be absolute. Management of individual cases must be subject to the clinical judgment of the professionals involved in the care of the patient, and management may deviate from these guidelines if clinical circumstances warrant.

It is also recognized that this document will evolve. As our experience with these patients increases it is expected that these guidelines should change.

Perioperative Management

Patients presenting for elective surgery will usually have been seen in the preanesthetic clinic. There will be two major types of sleep apnea patients encountered in the clinic:

A. Patients previously diagnosed with sleep apnea syndrome (SAS)

  1. Patients treated with CPAP will need to bring their machines with them to the hospital when they are admitted for surgery.
  2. Risk stratification according to severity of sleep apnea and type of surgery will be conducted. The degree of compliance with treatment and the success of treatment should be assessed.
  3. Patients who are highly symptomatic despite diagnosis and treatment should be referred for Chest Medicine assessment and optimization before proceeding for elective surgery unless the urgency of the proposed surgical procedure is extreme. If surgery must proceed, Chest Medicine should be consulted to follow these patients during their hospital stay.
  4. Preliminary plans for the postoperative management of these patients will be made preoperatively. Options include admission to the ICU, admission to a monitored area on the ward, admission to a surgical ward, or discharge to home. If it is felt that the patient will require admission to a monitored area, the chart must be flagged so that the manager of the receiving unit can make appropriate arrangements prior to the date of surgery.

B. Patients with suspected SAS

  1. Formal risk stratification should be done in the preanesthetic clinic.
  2. Patients suspected of having severe sleep apnea should not necessarily proceed for elective surgery. These patients should have a [pulmonary] Chest Medicine consultation, a diagnostic polysomnographic study, and optimization with CPAP therapy prior to surgery unless the urgency of the proposed surgical procedure is extreme.
  3. Consideration should also be given to referring less severe patients for diagnosis before proceeding with elective surgery.
  4. Initial plans for the postoperative management of these patients will be made. Options include admission to the ICU, admission to a monitored area on the ward, admission to a surgical ward, or discharge home. If it is felt that the patient will require admission to a monitored area, the chart must be flagged so that the manager of the receiving unit can make appropriate arrangements prior to the date of surgery.

Postoperative Management of Previously Diagnosed and Suspected SAS

The principles of patient disposition take into account both the severity of SAS, the effects of the surgical procedure, and the postoperative analgesic regimen.

Procedures can be described as high, intermediate, and low risk. High risk procedures include all cases entering body cavities, all large joint replacements, upper airway cases, and/or cases requiring parenteral or long-acting neuraxial opioids. Intermediate risk procedures are those not included in the high-risk category that require parenteral or long-acting neuraxial opioids. Low risk procedures are the same as intermediate risk but for which postoperative pain can be managed with oral medications, codeine being the most potent. The Acute Pain Service should be consulted for all SAS patients having high and intermediate risk procedures.

Options for postoperative disposition are monitored area (M), standard ward bed (W), or home (H). The proposed disposition would be as in Table 2.

Table 2. Sleep Apnea Scale

Surgical Risk
Severe
Moderate
Mild
High
M
M
M/W*
Intermediate
M
M/W*
W
Low
W
W/H*
W/H*
*Cases where there is an option should be dealt with on an individual basis, and there should be agreement among the involved consultants.
M=monitored area
W=standard ward
H=home

The physicians involved in the patient’s care should ensure that an appropriate postoperative disposition is arranged prior to beginning the case.

Patients having low risk procedures performed under local or regional anesthesia with little or no sedation and no neuraxial opioids can be discharged home the same day.

After an overnight stay in a monitored area, if no respiratory interventions relating to SAS are required and the patient is otherwise stable, the patient can be transferred to a lower intensity nursing care unit.

R. Deutscher, MD
D. Bell, MD S. Sharma, MD
St. Boniface Hospital
Winnipeg, Manitoba