Recently, in the Respiratory and Critical Care Medicine ward of Hunan Aerospace Hospital, a patient who was already in a stable condition experienced a sharp decrease in blood oxygen saturation. What is going on? After repeated examination and analysis by doctors, it turned out to be caused by a often overlooked "hidden killer" - sleep apnea syndrome. What is sleep apnea syndrome? What are the hazards and causes of it? What aspects of prevention should we start from? Zhou Zhiping, Director and Chief Physician of the Department of Respiratory and Critical Care Medicine at Hunan Aerospace Hospital, explains and clarifies doubts for everyone. The patient's condition is stable, but the blood oxygen saturation suddenly drops. Recently, in the Respiratory and Critical Care Medicine ward of Hunan Aerospace Hospital, the sharp alarm sound of the monitor suddenly sounded, and the eye-catching "70%" flashing on the screen. The blood oxygen saturation of a 42 year old female patient dropped sharply. The on duty doctor's heart tightened. This middle-aged woman who was hospitalized due to a "lung infection" was supposed to be in a stable period after treatment, but her blood oxygen saturation repeatedly fell into the abyss of "70%"? What is the reason? The doctor focused on scanning the monitoring data and found that the pulse oximeter was correctly worn on her finger, not due to measurement errors. In the end, his gaze fell on the patient's face, with a furrowed brow and purple lips. Although she was struggling to breathe, she did not actually wake up. Surprisingly, her snoring was intermittent, and after holding her breath, she suddenly took a deep breath... Finally, the truth was revealed: this heart stopping "blood oxygen alarm" was not caused by a lung infection, but by a hidden "killer" in the late night - sleep apnea syndrome. Sleep apnea syndrome, explained by Zhou Zhiping, a healthy "all rounder killer", refers to the cessation of respiratory airflow during sleep due to obstruction or other reasons, that is, holding breath or stopping breathing during sleep, lasting for more than 10 seconds or air flow lower than 20% of normal, which is known as sleep apnea syndrome. Its pathogenesis may be complete or incomplete upper airway obstruction, which can cause intermittent hypoxia, hypercapnia and sleep structure disorder, and can lead to multiple organ and multiple system damage such as hypertension, coronary heart disease, arrhythmia, cerebrovascular disease, cognitive dysfunction, type 2 diabetes, so it is called the "all-around killer" of sleep and health. As a chronic progressive disease, the sudden death rate of the patient population is three times higher than that of the population without the disease. Its typical symptoms include snoring during sleep, accompanied by repeated episodes, and the state of holding one's breath and then suddenly taking a deep breath; Dry mouth and headache in the morning; Daytime fatigue, drowsiness, increased nocturia, etc; Mental symptoms such as lack of concentration, decreased memory, irritability, anxiety or depression. Accompanied by symptoms, patients may exhibit symptoms of multiple system damage. In the cardiovascular system, there may be elevated blood pressure, arrhythmia, and even sudden cardiac death; The endocrine system may experience insulin resistance, abnormal glucose metabolism, metabolic syndrome, etc; The respiratory system can induce respiratory failure, worsen asthma, and also cause refractory chronic cough, pulmonary hypertension, pulmonary embolism, interstitial lung disease, etc. Patients may experience chest discomfort and suffocation; The urinary and reproductive system may experience increased nocturia, decreased adult libido, erectile dysfunction, etc; The digestive system may experience acid reflux, liver dysfunction, etc; The nervous system may experience a decline in children's attention and cognitive abilities, while adults may experience emotional states such as anxiety and depression. Obesity is an important triggering factor for sleep apnea syndrome. Zhou Zhiping introduced that multiple factors causing upper airway stenosis or decreased ability to maintain open function are the causes of sleep apnea syndrome. If the airway is completely blocked, it can cause respiratory arrest. The main triggering factors that affect this process include obesity, which is an important triggering factor for the disease, especially centripetal obesity, and the disease itself can exacerbate obesity. Diseases related to the nose are also contributing factors, such as deviated nasal septum, enlarged nasal turbinates, nasal polyps, nasal tumors, adenoid hyperplasia, soft palate laxity, uvula hypertrophy, and pharyngeal stenosis; Enlarged tongue body and posterior drooping of tongue base; Softening of laryngeal and tracheal cartilage; Maxillofacial developmental abnormalities, etc. The incidence of adult diseases increases with age and gender; The ratio of male to female disease incidence is about 2:1, with a significant increase in incidence among postmenopausal women. Family history, this disease has familial clustering. Genetic predisposition can manifest in children with excessive adenoid hyperplasia, enlarged mandibular tonsils, structural variations in the maxillofacial region, obesity, and respiratory center sensitivity. Individuals with a family history have a 2-4 fold increased risk of developing the disease. Drinking alcohol and medication, as well as taking sedatives and hypnotic drugs, can induce sleep apnea syndrome. Smoking can trigger or worsen the disease through chronic inflammation of the upper airway and transient withdrawal effects from sleep; Environmental pollutants and second-hand smoke are also triggering factors for children to develop this disease. Other related diseases, such as cerebrovascular disease, congestive heart failure, endocrine disorders (hypothyroidism and acromegaly, etc.), vocal cord paralysis, brain tumors, neuromuscular diseases, pharyngeal reflux, upper mediastinal masses, etc., can cause or worsen the disease by affecting airway structure or nerve function. Prevention: lose weight, quit smoking and drinking, try to sleep on your side. What should you do if you suspect you have sleep apnea syndrome? Zhou Zhiping stated that it is necessary to go to the hospital to improve multi-channel sleep monitoring, which is the gold standard for diagnosing this disease. It can record physiological signals such as electroencephalography, electrocardiography, electromyography, electrooculography, chest and abdominal breathing, snoring, mouth and nose airflow, blood oxygen saturation, limb movement, and body position during sleep, as well as audio and video data, to determine the presence of hypoventilation, apnea, and other conditions. After diagnosis, mild patients are recommended to manage their diet, posture, and other aspects, such as weight loss, quitting smoking and drinking, using sedative and hypnotic drugs with caution, and other drugs that may cause or worsen respiratory pauses, avoiding excessive fatigue, etc. They can also reduce tongue heaviness by lying on their side. For moderate to severe patients, professional doctors need to fully evaluate the condition and choose different treatment methods. Currently, treatment methods include mechanical ventilation, surgical treatment, and orthodontic treatment. In terms of prevention, we can start from the following aspects: managing weight well: Obesity is the primary modifiable risk factor, especially central obesity. Fat accumulation can compress the upper airway, leading to collapse. The body mass index (BMI) should be between 18.5-23.9, with a waist circumference of less than 90 centimeters for males and less than 85 centimeters for females. Abstain from smoking and alcohol: Try to avoid sedatives as tobacco can damage respiratory mucosa, exacerbate inflammation and edema; Alcohol and sleeping pills cause relaxation of the throat muscles, exacerbating airway obstruction; Abstain from alcohol within 4 hours before bedtime. Pay attention to sleeping position: Training in a lateral sleeping position can reduce the fall of the tongue and improve ventilation (gravity can easily cause airway collapse when lying down), and can also be assisted by specialized position pillows. Disease management and intervention for high-risk factors: such as nasopharyngeal diseases, deviated nasal septum, nasal polyps, adenoid/tonsillar hypertrophy requiring surgical correction; Endocrine diseases and hypothyroidism require supplementation with thyroid hormone; Acromegaly requires control of growth hormone and other factors. (New Society)