Clinical practice guideline for diagnostic testing for adult obstructive sleep apnea: an American Academy of Sleep Medicine clinical practice guideline

INTRODUCTION: This guideline establishes clinical practice recommendations for the diagnosis of obstructive sleep apnea (OSA) in adults and is intended for use in conjunction with other American Academy of Sleep Medicine (AASM) guidelines on the evaluation and treatment of sleep-disordered breathing in adults. METHODS: The AASM commissioned a task force of experts in sleep medicine. A systematic review was conducted to identify studies, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) process was used to assess the evidence. The task force developed recommendations and assigned strengths based on the quality of evidence, the balance of benefits and harms, patient values and preferences, and resource use. In addition, the task force adopted foundational recommendations from prior guidelines as "good practice statements", that establish the basis for appropriate and effective diagnosis of OSA. The AASM Board of Directors approved the final recommendations. RECOMMENDATIONS: The following recommendations are intended as a guide for clinicians diagnosing OSA in adults. Under GRADE, a STRONG recommendation is one that clinicians should follow under most circumstances. A WEAK recommendation reflects a lower degree of certainty regarding the outcome and appropriateness of the patient-care strategy for all patients. The ultimate judgment regarding propriety of any specific care must be made by the clinician in light of the individual circumstances presented by the patient, available diagnostic tools, accessible treatment options, and resources. Good Practice Statements: Diagnostic testing for OSA should be performed in conjunction with a comprehensive sleep evaluation and adequate follow-up. Polysomnography is the standard diagnostic test for the diagnosis of OSA in adult patients in whom there is a concern for OSA based on a comprehensive sleep evaluation.Recommendations: We recommend that clinical tools, questionnaires and prediction algorithms not be used to diagnose OSA in adults, in the absence of polysomnography or home sleep apnea testing. (STRONG). We recommend that polysomnography, or home sleep apnea testing with a technically adequate device, be used for the diagnosis of OSA in uncomplicated adult patients presenting with signs and symptoms that indicate an increased risk of moderate to severe OSA. (STRONG). We recommend that if a single home sleep apnea test is negative, inconclusive, or technically inadequate, polysomnography be performed for the diagnosis of OSA. (STRONG). We recommend that polysomnography, rather than home sleep apnea testing, be used for the diagnosis of OSA in patients with significant cardiorespiratory disease, potential respiratory muscle weakness due to neuromuscular condition, awake hypoventilation or suspicion of sleep related hypoventilation, chronic opioid medication use, history of stroke or severe insomnia. (STRONG). We suggest that, if clinically appropriate, a split-night diagnostic protocol, rather than a full-night diagnostic protocol for polysomnography be used for the diagnosis of OSA. (WEAK). We suggest that when the initial polysomnogram is negative and clinical suspicion for OSA remains, a second polysomnogram be considered for the diagnosis of OSA. (WEAK).

Rates of sensor loss in unattended home polysomnography: the influence of age, gender, obesity, and sleep-disordered breathing.

OBJECTIVES: To evaluate study failure and sensor loss in unattended home polysomnography and their relationship to age, gender, obesity, and severity of sleep-disordered breathing (SDB). DESIGN: A cross-sectional analysis of data gathered prospectively for the Sleep Heart Health Study (SHHS). SETTING: Unattended polysomnography was performed in participants' homes by the staff of the sites that are involved in SHHS. PARTICIPANTS: 6,802 individuals who met the inclusion criteria (age >40 years, no history of treatment of sleep apnea, no tracheostomy, no current home oxygen therapy) for SHHS. RESULTS: A total of 6802 participants had 7151 studies performed. 6161 of 6802 initial studies (90.6%) were acceptable. Obesity was associated with a decreased likelihood of a successful initial study. After one or more attempts, 6440 participants (94.7%) had studies that were judged as acceptable. The mean duration of scorable signals for specific channels ranged from 5.7 to 6.8 hours. The magnitudes of the effects of age, gender, BMI, and RDI on specific signal durations were not clinically significant. CONCLUSION: Unattended home PSG as performed for SHHS was usually successful. Participant characteristics had very weak associations with duration of scorable signal. This study suggests that unattended home PSG, when performed with proper protocols and quality controls, has reasonable success rates and signal quality for the evaluation of SDB in clinical and research settings.

Effects of varying approaches for identifying respiratory disturbances on sleep apnea assessment.

Varying approaches to measuring the respiratory disturbance index (RDI) may lead to discrepant estimates of the severity of sleep-disordered breathing (SDB). In this study, we assessed the impact of varying the use of corroborative data (presence and degree of desaturation and/or arousal) to identify hypopneas and apneas. The relationships among 10 RDIs defined by various definitions of apneas and hypopneas were assessed in 5,046 participants in the Sleep Heart Health Study (SHHS) who underwent overnight unattended 12-channel polysomnography (PSG). The magnitude of the median RDI varied 10-fold (i.e., 29.3 when the RDI was based on events identified on the basis of flow or volume amplitude criteria alone to 2.0 for an RDI that required an associated 5% desaturation with events). The correlation between RDIs based on different definitions ranged from 0.99 to 0.68. The highest correlations were among RDIs that required apneas and hypopneas to be associated with some level of desaturation. Lower correlations were observed between RDIs that required desaturation as compared with RDIs defined on the basis of amplitude criteria alone or associated arousal. These data suggest that different approaches for measuring the RDI may contribute to substantial variability in identification and classification of the disorder.

Association of hypothyroidism and obstructive sleep apnea.

Obstructive sleep apnea (OSA) and hypothyroidism are relatively common disorders that have similar clinical features and are thought to be causally linked. We sought to determine the prevalence of previously unrecognized hypothyroidism in a series of patients evaluated for OSA and whether an association between hypothyroidism and OSA was present. Chart review was used to obtain information on thyroid function status, polysomnography results, levothyroxine use, and clinical signs and symptoms in 336 consecutive adult patients who underwent polysomnography for suspected OSA. In addition, levothyroxine use was determined in age- and sex-matched control subjects for the purposes of a case-control study. Among the patients without prior history of hypothyroidism who underwent polysomnography and thyroid function testing, four new cases or 1. 41% (95% CI 0.04-2.78) were found to have subclinical hypothyroidism. Our findings do not support routine thyroid screening by specialists in patients referred for polysomnography. The odds ratio of the association of prior history of hypothyroidism to OSA was 1. 47 (95% CI 0.8-2.8). Limitations in study design may have limited our ability to detect a statistically significant association between OSA and hypothyroidism.

Association of extrarenal Wilms' tumor with a horseshoe kidney.

Nephroblastoma (Wilms' tumor) is the most common renal malignancy in childhood. Extrarenal Wilms' tumor is uncommon, and the diagnosis is almost always postsurgical. The authors report two cases, located in the sigmoid mesocolon, one of these having an associated horseshoe kidney. Both were treated with excision followed by chemotherapy. They are now 36 months and 7 months postchemotherapy, respectively, and are symptom and recurrence free. Both had favorable histological findings. Association with a horseshoe kidney raises an important issue regarding the histogenesis of these tumors. The authors believe that there is a nexus between the fusion of metanephric blastema during the sixth to seventh week of intrauterine life and the "ectopic" metanephric blastema cells that may give rise to extrarenal Wilms' tumor. Association with a horseshoe kidney with an extrarenal Wilms' tumor has been reported on five previous occasions. The authors closely examine the link between the two.

Asymmetric conjoined twins.

Despite recent advances in diagnosis, particularly organ-imaging, and therapeutic options, the management of conjoined twins is still very challenging. We report conjoined twins attached ()end-on" at the lumbo-sacral level and describe the anatomical findings, methods of investigation, and management.

Short colon variant.

A one day old neonate with a short colon, associated exomphalos minor; bifid scrotum and ileovesical fistula is reported.

Tropical enterocolitis in children.

Besides classical necrotizing enterocolitis (in neonates), which is seen in India as elsewhere in the world, we observe sporadic cases of tropical enterocolitis, i.e. segmental jejunitis, ileitis or colitis and rarely duodenitis. This is a distinct clinico-pathological entity presenting as "acute abdomen", with pain, bilious vomiting, constipation or bloody diarrhoea. The clinical course is not as fulminating as neonatal necrotizing enterocolitis. Most cases are salvaged by conservative treatment especially after the confidence brought by laparoscopic vision of the abdomen, thus excluding perforation or gangrene of the bowel involved. Without laparoscopy, most of the cases end up in laparotomy. The pathology appears to be a kind of local hyperimmune reaction in the segment of bowel involved, ranging from punctate haemorrhages in the seromuscular layer of the bowel to a generalized red fiery look or perforation due to mucosal ulceration. Whatever the causative agent, the pathogenesis is of local vasculitis leading to ischemia and various patterns of disease.

Endodermal sinus tumor: report of 12 cases.

Twelve cases of endodermal sinus tumor were reviewed. There were 10 females and 2 males with a median age at presentation of 3 years. The primary site was sacrococcygeal in 4 patients, vaginal in 3, retroperitoneal in 2, and testicular, ovarian and left chest wall in one each. The diagnosis rested on histopathological examination and elevation of serum alfa feto protein levels (median 46,200 ng/ml). Two patients had Stage I disease, 9 had Stage III and one had Stage IV disease. Patients were managed by surgery and chemotherapy (BVP regime). All patients on BVP (even those lost at later stages), had achieved clinical remission with the first cycle of treatment.

Neonatal gastrointestinal perforations.

Fourteen neonates presented with clinical and radiological evidence of gastrointestinal perforation, of which 13 were treated by operative intervention. No infant was formula fed, had rectal bleeding or radiological evidence of pneumatosis intestinalis. Operative findings revealed localized perforation in ten of which three were gastric, two distal ileal, three cecal and two in sigmoid colon. Gangrene with extensive perforation of jejunum, ascending colon and transverse colon were seen in one each. Blood cultures were positive in four, one grew E. coli and three Klebsiella while peritoneal cultures were positive in six, one grew E. coli and five Klebsiella. Ten neonates survived and are being followed up. Three of the four cases who died had white blood cell count greater than 25 x 109/L and grew Klebsiella on peritoneal culture. Factors predisposing to gastrointestinal perforations in neonates are discussed, emphasis is made on the cautious use of umbilical, gastric and rectal catheters, and the need for early surgical intervention.

Posterior midline cervical fetal cystic hygroma.

Posterior midline cervical cystic hygromas (PMC) are frequently found associated with chromosomal aberrations and usually do not survive. The present report illustrates diagnosis of this condition by sonography in an 18 weeks old fetus and an amniocentesis revealed 45 x0 karyotype and increased concentration of alpha-fetoproteins. Pregnancy was terminated in view of Turner's syndrome. The etiology and natural history of the condition is reviewed.

Abdominal tuberculosis in children.

Fifty cases of abdominal tuberculosis, seen over a 10-year period, are reviewed. A mass in the abdomen, with or without intestinal obstruction, was the commonest mode of presentation. Biochemical, haematological and bacteriological tests were of limited help in making a definite diagnosis, which was largely based on laparoscopic findings or on biopsy material obtained at operation. Laparoscopy was considered a simple, safe and reliable method for diagnosis, and it was at times possible to avoid a laparotomy. At operation, only the minimum of surgery was attempted. Division of bands, adhesiolysis, and conservative resection were performed, according to the intraoperative findings. Bypass operations are reserved for duodenal obstruction or extensively involved bowel. The prognosis was found to be excellent and the mortality negligible.