La polisomnografía de siesta (PSG-S) es un método abreviado de diagnóstico en el síndrome de apnea-hipopnea del sueño (SAHS). Aunque el diagnóstico de SAHS se establece con un índice de apnea-hipopnea (IAH) mayor de 10, el tratamiento con ventilación a presión positiva continua nasal (CPAP) se inicia con un IAH superior a 30

Conocer la rentabilidad diagnóstica de la PSG-S para iniciar el tratamiento con CPAP y evaluar los diferentes tipos de registros polisomnográficos hallados

A 296 pacientes con sospecha clínica de SAHS se les realizó una PSG-S de 3 h de duración. Las PSG-S se consideraron: a) positivas cuando el IAH era mayor de 30; b) normales cuando el IAH era inferior a 10 con sueño NREM y REM (mayor del 10%); c) nulas si el paciente durmió menos de 60 min, y d) no concluyentes, donde se definieron 3 subgrupos: IAH entre 10 y 30 con REM; IAH menor de 30 sin REM y sospecha de síndrome de resistencia aumentada de la vía aérea superior (SRAVAS)

La suma de las polisomnografías positivas y las normales se consideró diagnóstica; la suma de las nulas y las no concluyentes se consideró no diagnóstica. Según el episodio respiratorio más frecuente, las polisomnografías de siesta positivas fueron consideradas obstructiva predominante, hipopnea predominante, central-mixta, central-obstructiva y miscelánea

En un 70% las PSG fueron diagnósticas (55% positivas más 15% normales), y el 30% no diagnósticas (12% nulas más 18% no concluyentes). Las PSG-S positivas se desglosaron en obstructivas predominantes (55%), hipopneas predominantes (29%), central-mixta (8%), central-obstructiva (4%) y miscelánea (4%)

La rentabilidad diagnóstica de la PSG-S para iniciar tratamiento con CPAP es elevada y existe una notable frecuencia del subgrupo definido como “hipopneas predominantes”

Nap polysomnography (NPSG) is a technique for rapid diagnosis of sleep apnea-hypopnea syndrome (SAHS). Although an apnea-hypopnea index (AHI) over 10 indicates a diagnosis of SAHS, treatment with nasal continuous positive airway pressure (CPAP) starts when the AHI exceeds 30

To determine the diagnostic yield of NPSG for initiating CPAP and to evaluate the different types of polysomnographic findings

Two hundred ninety-six patients suspected of having SAHS underwent NPSG lasting three hours. NPSG findings were considered positive at AHI > 30; normal at AHI < 10 with non-REM and REM sleep (more than 10%); invalid if the patient slept less than 60 minutes; and inconclusive if AHI was between 10 and 30 with REM, if AHI was < 30 without REM, or if upper airway resistance syndrome (UAS) was suspected

Positive and normal polysomnographic findings were considered diagnostic and the invalid and inconclusive findings were considered non-diagnostic. We also observed whether SAHS was predominantly obstructive, predominantly hypopneic, central-mixed, central-obstructive or miscellaneous, based on the type of event detected mot often during NPSG

Seventy percent of the NPSG were diagnostic (55% positive and 15% normal) and 30% were not (12% invalid and 18% inconclusive). Fifty-five percent of the positive NPSGs were predominantly obstructive, 29% were predominantly hypopneic, 8% were central-mixed, 4% were central-obstructive and 4% were miscellaneous

The diagnostic value of NPSG for initiating CPAP treatment is high. Predominantly hypopneic forms are particularly common