Obstructive sleep apnea syndrome and perioperative complications: a systematic review of the literature.

Obstructive sleep apnea syndrome (OSAS) is a common sleep related breathing disorder. Its prevalence is estimated to be between 2% and 25% in the general population. However, the prevalence of sleep apnea is much higher in patients undergoing elective surgery. Sedation and anesthesia have been shown to increase the upper airway collapsibility and therefore increasing the risk of having postoperative complications in these patients. Furthermore, the majority of patients with sleep apnea are undiagnosed and therefore are at risk during the perioperative period. It is important to identify these patients so that appropriate actions can be taken in a timely fashion. In this review article, we will discuss the epidemiology of sleep apnea in the surgical population. We will also discuss why these patients are at a higher risk of having postoperative complications, with the special emphasis on the role of anesthesia, opioids, sedation, and the phenomenon of REM sleep rebound. We will also review how to identify these patients preoperatively and the steps that can be taken for their perioperative management

The Determining Risk of Vascular Events by Apnea Monitoring (DREAM) Study: Design, Rationale and Methods

Purpose The goal of the Determining Risk of Vascular Events by Apnea Monitoring (DREAM) study is to develop a prognostic model for cardiovascular outcomes, based on physiologic variables—related to breathing, sleep architecture, and oxygenation—measured during polysomnography in US veterans. Methods The DREAM study is a multi-site, retrospective observational cohort study conducted at three Veterans Affairs (VA) centers (West Haven, CT; Indianapolis, IN; Cleveland, OH). Veterans undergoing polysomnography between January 1, 2000 and December 31, 2004 were included based on referral for evaluation of sleep-disordered breathing, documented history and physical prior to sleep testing, and ≥2-h sleep monitoring. Demographic, anthropomorphic, medical, medication, and social history factors were recorded. Measures to determine sleep apnea, sleep architecture, and oxygenation were recorded from polysomnography. VA Patient Treatment File, VA–Medicare Data, Vista Computerized Patient Record System, and VA Vital Status File were reviewed on dates subsequent to polysomnography, ranging from 0.06 to 8.8 years (5.5 ± 1.3 years; mean ± SD). Results The study population includes 1840 predominantly male, middle-aged veterans. As designed, the main primary outcome is the composite endpoint of acute coronary syndrome, stroke, transient ischemic attack, or death. Secondary outcomes include incidents of neoplasm, congestive heart failure, cardiac arrhythmia, diabetes, depression, and post-traumatic stress disorder. Laboratory outcomes include measures of glycemic control, cholesterol, and kidney function. (Actual results are pending.) Conclusions This manuscript provides the rationale for the inclusion of veterans in a study to determine the association between physiologic sleep measures and cardiovascular outcomes and specifically the development of a corresponding outcome-based prognostic model

Obstructive sleep apnoea in adults

Obstructive sleep apnoea (OSA) is characterised by repetitive closure of the upper airway, repetitive oxygen desaturations and sleep fragmentation. The prevalence of adult OSA is increasing because of a worldwide increase in obesity and the ageing of populations. OSA presents with a variety of symptoms the most prominent of which are snoring and daytime tiredness. Interestingly though, a significant proportion of OSA sufferers report little or no daytime symptoms. OSA has been associated with an increased risk of cardiovascular disease, cognitive abnormalities and mental health problems. Randomised controlled trial evidence is awaited to confirm a causal relationship between OSA and these various disorders. The gold standard diagnostic investigation for OSA is overnight laboratory-based polysomnography (sleep study), however, ambulatory models of care incorporating screening questionnaires and home sleep studies have been recently evaluated and are now being incorporated into routine clinical practice. Patients with OSA are very often obese and exhibit a range of comorbidities, such as hypertension, depression and diabetes. Management, therefore, needs to be based on a multidisciplinary and holistic approach which includes lifestyle modifications. Continuous positive airway pressure (CPAP) is the first-line therapy for severe OSA. Oral appliances should be considered in patients with mild or moderate disease, or in those unable to tolerate CPAP. New, minimally invasive surgical techniques are currently being developed to achieve better patient outcomes and reduce surgical morbidity. Successful longterm management of OSA requires careful patient education, enlistment of the family’s support and the adoption of self-management and patient goal-setting principles.Australian National Health and Medical Research Counci

Long-term CPAP use in obstructive sleep apnea : Effects on cardiovascular outcomes, weight control and motor vehicle accidents

Obstructive sleep apnea (OSA) is a common disorder associated with various adverse health effects, including an increased risk of cardiovascular disease (CVD) events, metabolic dysregulation, and motor vehicle accidents (MVA). This study evaluated the long-term effects of continuous positive airway pressure (CPAP), the primary treatment for OSA, in a large retrospective cohort of 1030 CPAP-adherent patients and 1030 controls matched for age, gender and apnea-hypopnea index (AHI). Controls had discontinued CPAP treatment despite their doctor’s advice. Approximately one half of the patients commencing CPAP had continued the treatment for 5 years, generally with good short- and long-term adherence. Only a weak positive correlation was found between AHI and long-term CPAP usage, while no association could be verified between AHI and the risk of CVDs or MVAs. CPAP-treated patients at the cohort level had a slight weight gain at a comparable rate to that observed in the general middle-aged Finnish population, while 10 % of the patients at the individual level had a significant weight gain. Those individuals, at baseline, were already more severely obese despite being younger than the rest of the cohort. An association between CPAP and a reduced risk of CVDs and all-cause mortality, in comparison to controls, was observed over a median follow-up of 9 years but only among those with CPAP use of >4–6 h/day. The incidence of MVAs did not change when compared 9 years before and after treatment or in CPAP-treated patients and controls regardless of the level of adherence. The results of the present study emphasize that OSA is a heterogeneous disease, and the use of AHI alone is insufficient to assess OSA severity or to identify highrisk patients for adverse outcomes. The results further imply that CPAP use of >4–6 h/day is needed to achieve potential improvements in CVD risk. Patients are more likely to gain than lose weight during CPAP treatment, underlying the urge for lifestyle interventions. The incidence of MVAs did not change after CPAP use, suggesting that the MVA risk is likely to be multifactorial, and even longer observation periods may be needed to detect a significant difference.Pitkäaikainen CPAP-hoito uniapneapotilailla: vaikutukset sydän- ja verisuonitautisairastavuuteen, painonhallintaan ja liikenneonnettomuusalttiuteen Obstruktiivinen uniapnea on yleinen sairaus, johon liittyy vakavia terveysriskejä, kuten sydän- ja verisuonisairaudet, aineenvaihdunnan toimintahäiriöt ja suurentunut liikenneonnettomuusalttius. Tämä tutkimus kartoitti takautuvasti obstruktiivisen uniapnean ensisijaisen hoitomuodon, ylipaine- eli CPAP-hoidon vaikuttavuutta. Tutkimuksessa oli mukana 1030 pitkäaikaisesti hoitoon sitoutunutta potilasta ja 1030 iän, sukupuolen ja apnea-hypopneaindeksin (AHI) suhteen kaltaistettua verrokkia, jotka olivat lopettaneet CPAP-hoidon lääkärin suosituksesta huolimatta. Keskimäärin puolet hoidon aloittaneista oli jatkanut hoitoa >-5 vuotta. Hoitoon sitoutuminen oli hyvällä tasolla sekä lyhyt- että pitkäaikaisesti. Heikko tilastollinen vastaavuus havaittiin AHI:n ja pitkäaikaisten käyttötuntien välillä, mutta yhteyttä AHI:n ja sydän- ja verisuonitautisairastavuuden tai liikenneonnettomuusriskin välillä ei todettu. Ryhmätasolla havaittiin vähäinen painonnousu, joka oli vastaava kuin suomalaisessa keski-ikäisessä väestössä yleensä. Yksilötasolla 10 % potilaista lihoi merkittävästi. Nuoremmasta iästään huolimatta he olivat jo lähtötilanteessa vaikeammin lihavia kuin muut tutkimuspotilaat. Verrokkiryhmään verrattuna CPAP-hoidon käyttö >4–6 tuntia päivässä liittyi pienempään sydän- ja verisuonitautisairastavuuteen ja kokonaiskuolleisuuteen 9 vuoden seuranta-aikana. Liikenneonnettomuuksien esiintyvyys ei muuttunut, kun potilaita verrattiin 9 vuotta ennen ja jälkeen hoidon, käyttötuntien perusteella tai suhteessa verrokkipotilaisiin. Tulosten perusteella obstruktiivinen uniapnea on monimuotoinen sairaus, jonka vaikeusastetta ei voida luotettavasti arvioida eikä suurimmassa terveysriskissä olevia tunnistaa pelkän AHI:n perusteella. Mahdollinen suotuisa vaikutus sydän- ja verisuonitautisairastavuuteen edellyttänee CPAP-hoidon käyttöä >4–6 tuntia päivässä. Lihominen hoidon aikana on todennäköisempää kuin laihtuminen painottaen elintapahoitojen tärkeyttä. Liikenneonnettomuuksien esiintyvyys ei muuttunut CPAP-hoidon myötä. Liikenneonnettomuuteen joutuminen on todennäköisesti monitekijäinen tapahtuma ja pidempi seuranta-aika saattaa olla tarpeen, jotta merkittävä ero voitaisiin havaita