Altitude and Breathing during Sleep in Healthy Persons and Sleep Disordered Patients: A Systematic Review.

Objetive The aim of this systematic review is to analyze the recent scientific evidence of the clinical effects of altitude on breathing during sleep in healthy persons and sleep disordered patients. Material and Methods A search was carried out in PubMed and Scopus looking for articles published between January 1, 2010 and December 31, 2021, in English and Spanish, with the following search terms: "sleep disorders breathing and altitude". Investigations in adults and carried out at an altitude of 2000 meters above mean sea level (MAMSL) or higher were included. The correlation between altitude, apnea hypopnea index (AHI) and mean SpO2 during sleep was calculated. Results 18 articles of the 112 identified were included. A good correlation was found between altitude and AHI (Rs = 0.66 P = 0.001), at the expense of an increase in the central apnea index. Altitude is inversely proportional to oxygenation during sleep (Rs = -0.93 P = 0.001), and an increase in the desaturation index was observed (3% and 4%). On the treatment of respiratory disorders of sleeping at altitude, oxygen is better than servoventilation to correct oxygenation during sleep in healthy subjects and acetazolamide controlled respiratory events and oxygenation during sleep in patients with obstructive sleep apnea under treatment with CPAP. Conclusions Altitude increases AHI and decreases oxygenation during sleep; oxygen and acetazolamide could be an effective treatment for sleep-disordered breathing at altitude above 2000 MAMSL.

Quality of an ambulatory monitoring technique for diagnosing obstructive sleep apnea under conditions of limited resources.

OBJECTIVES: To: 1) evaluate the quality of an ambulatory monitoring technique for diagnosing Obstructive Sleep Apnea Syndrome (OSAS) while patients move through the city; and 2) identify factors that lead to data loss. METHODS: Clinical histories were reviewed and ambulatory portable monitorings of adults with high pretest probability for OSAS were included, the signals monitored were pulse oximetry, heart rate, nasal pressure, snoring, chest band and body position. The equipment was connected from 14:00-20:00 h and then patients moved through the city turning it off and on at home. Results were analyzed visually to record all the minutes lost. A good-quality study was defined as recording time 240 min and signal loss <20%. A cost/benefit analysis was performed using Golpe et al.'s methodology. RESULTS: A total of 70 recordings were analyzed. Most subjects were obese men with severe OSAS. Signal quality was determined to be good with a median signal loss of 4.9 min (0-405) that represented 1% (0-99) of total recording time. The signal lost most often was pulse oximetry at 1.8 min (0-403, p=0.0001). Of the 70 studies performed, 57 (81%) met the definition of good quality, while 13 (19%) had to be repeated. Men lost the pulse oximetry signal more often than women. This technique could represent savings of 65-75%. CONCLUSIONS: Placing a portable OSAS monitor during the day while patients move around the city turning it on and off at home does not affect the quality of the study results obtained and is a cost-effective method.

Síndrome de hipoventilación alveolar central congénita / Congenital central alveolar hypoventilation syndrome

ResumenIntroducción: El síndrome de hipoventilación alveolar central congénita (SHACC) es un raro trastorno respiratorio del dormir, aunque cada vez más frecuentemente diagnosticado en clínicas de sueño y servicios de neumología pediátrica. Si bien se desconoce su epidemiología, en la literatura médica existen cerca de 300 casos reportados, y su incidencia es de 1 caso por cada 200,000 recién nacidos vivos. Se caracteriza por hipoventilación alveolar que se presenta o empeora durante el sueño. Es secundario a la disminución/ausencia de la respuesta ventilatoria a la hipercapnia o hipoxemia, y en el 90% de los casos es debido a una mutación tipo PARM del gen PHOX2B. Su tratamiento incluye ventilación mecánica y marcapasos diafragmático. Si la terapéutica no se inicia en forma temprana, el paciente desarrollará insuficiencia respiratoria crónica, hipertensión arterial pulmonar, cor pulmonale y la muerte.Casos clínicos: Se presentan tres casos de SHACC diagnosticados, tratados y en seguimiento en la Clínica de Trastornos Respiratorios del Dormir del Instituto Nacional de Enfermedades Respiratorias.Conclusiones: El diagnóstico temprano es importante para el inicio del soporte ventilatorio, y para prevenir el desarrollo de complicaciones y reducir la mortalidad.

AbstractBackground: Congenital central alveolar hypoventilation syndrome (CCAHS) is a rare sleep-related breathing disorder. Although increasingly frequently diagnosed in sleep clinics and pediatric pulmonology services, its epidemiology is not known. There are about 300 reported cases reported in the literature with an incidence of 1 case per 200,000 live births. CCAHS is characterized by alveolar hypoventilation that occurs or worsens during sleep and is secondary to a reduction/absence of the ventilatory response to hypercapnia and/or hypoxemia. In 90% of the cases it is due to a PARM-type mutation of the PHOX2B gene. Treatment includes mechanical ventilation and diaphragmatic pacemaker. If therapy is not initiated promptly the patient can evolve to chronic respiratory failure, pulmonary hypertension, cor pulmonale and death.Case reports: In this paper we present three cases of CCAHS diagnosed, treated and followed up at the Sleep Disorders Clinic of the National Institute of Respiratory Diseases in Mexico.Conclusions: Early diagnosis is important to initiate ventilatory support so as to prevent any complications and to reduce mortality.

[Congenital central alveolar hypoventilation syndrome]. / Síndrome de hipoventilación alveolar central congénita.

BACKGROUND: Congenital central alveolar hypoventilation syndrome (CCAHS) is a rare sleep-related breathing disorder. Although increasingly frequently diagnosed in sleep clinics and pediatric pulmonology services, its epidemiology is not known. There are about 300 reported cases reported in the literature with an incidence of 1 case per 200,000 live births. CCAHS is characterized by alveolar hypoventilation that occurs or worsens during sleep and is secondary to a reduction/absence of the ventilatory response to hypercapnia and/or hypoxemia. In 90% of the cases it is due to a PARM-type mutation of the PHOX2B gene. Treatment includes mechanical ventilation and diaphragmatic pacemaker. If therapy is not initiated promptly the patient can evolve to chronic respiratory failure, pulmonary hypertension, cor pulmonale and death. CASE REPORTS: In this paper we present three cases of CCAHS diagnosed, treated and followed up at the Sleep Disorders Clinic of the National Institute of Respiratory Diseases in Mexico. CONCLUSIONS: Early diagnosis is important to initiate ventilatory support so as to prevent any complications and to reduce mortality.