Medical Legal Alert: Pain Medication May Trigger Cardiopulmonary Arrest in Patients With Sleep Apnea
Apnea is defined as the absence of airflow at the nose and mouth for longer than 10 seconds. Sleep apnea syndrome (SAS) is described as the occurrence of more than 30 apnea episodes over a seven-hour period of nocturnal sleep. The majority of sleep apnea cases are obstructive as opposed to central. The upper airway becomes impeded while respiratory effort and diaphragmatic contraction still occur. In the absence of formal sleep studies, the diagnosis can be made clinically by interviewing patients and their sleeping partners. Clinical signs include loud snoring, observed apneic episodes, and excessive daytime somnolence.
Physiologic studies have demonstrated that patients with SAS have narrowed upper airways to start with, so they are more susceptible than other patients to drugs or anesthetics that suppress pharyngeal muscle tone. In normal, awake patients, there is a process whereby the muscles in the throat contract immediately before each breath, helping to resist the negative pressure generated by the diaphragm and keeping the airway open and free from collapsing. This process of contraction of the pharyngeal muscles is significantly reduced during REM sleep and by the use of narcotic pain medications. Patients with sleep apnea appear to be much more sensitive than normal individuals, even to minimal levels of narcotic pain medications such as morphine. Because of the impact of anesthetic drugs and narcotic pain medications on the breathing process, high-risk patients that have sleep apnea or are at increased risk of that condition need to be carefully monitored during and after surgical procedures.
At Mishkind Law Firm Co., L.P.A., we have experience in handling post surgical cases involving respiratory arrest and respiratory depression in high-risk patients that have a confirmed diagnosis or physical characteristics of obstructive sleep apnea. The increased sensitivity of their hypoglossal nerves to low doses of anesthesia has been well-described in the literature and needs to be carefully monitored.
Nursing Protocols Are Inadequate
Literature review suggests that the traditional nursing measurement of respiratory rate is ineffective in SAS patients for a number of reasons. Critical hypoxemia occurred during sporadic episodes of obstruction with continued respiratory effort that could be difficult to differentiate from effective respiration. These episodes were only rarely associated with slow respiratory rates (fewer than 10 breaths per minute), making rate alone an insensitive indicator of compromise. One solution would be to use audible pulse oximeter monitoring on the ward. Although this is not currently the standard of care, the apparent high incidence of respiratory obstruction in SAS patients should make this a strong consideration, especially if narcotic analgesics are to be used.
Diagnosing Sleep Apnea and Medical-Legal Implications
Sleep apnea should be suspected in patients with the classical body habitus of obesity with a short, thick neck. A history of loud snoring as reported by the sleeping partner is a cardinal sign mentioned in almost all case reviews. One study has suggested that snoring should be considered significant if any signs of obstruction were noted by a spouse or partner, including episodes of gasping and choking while asleep, the noise resulted in the need for the couple to sleep in different rooms or the snoring was associated with excessive daytime somnolence.
Although these signs are noted in a number of studies, these are not questions routinely asked by anesthesiologists. Perhaps not all patients exhibiting these symptoms will have sleep apnea if evaluated by formal sleep studies, but it might be safer to treat them as if they did until proven otherwise. Failure to recognize the potential signs of sleep apnea and risk associated with this condition in the face of surgery can lead to sudden and potentially catastrophic outcomes. If you or a loved one might have sleep apnea, be cautious about any upcoming surgery and do research on the signs and symptoms and the impact of anesthesia and pain medications on the breathing process. Make sure that you give a detailed medical history to your doctor, surgeon, anesthesiologist and nursing staff. Take the time to advise everyone involved ahead of time to avoid a potential disastrous outcome.
The medical legal team at Mishkind Law Firm Co., L.P.A. can help you or a loved one if you experience complications due to sleep apnea that were ignored or overlooked by the healthcare team. Let us help you. We will get your questions answered.
