Analysis of the upper-airway collapsibility in patients with renal disease in hemodialysis: preliminary results

Introduction: Currently, end stage renal disease (ESRD) is one of the most serious public health problems, becoming a global epidemic. It is also known that the amount of nocturnal rostral fluid shift from the lower limbs is related to increased neck circumference and the severity of obstructive sleep apnea (OSA) in ESRD patients. Objectives: To verify the degree of upper-airway collapsibility through the negative expiratory pressure test (NEP) in ESRD patients. Methods: A clinical trial study was carried out to verify the degree of upper-airway collapsibility in patients with ESRD. NEP test and nocturnal home polygraphy was be performed before and after the hemodialysis (HD) session. Results: There was a significant difference in pre and post HD in the apnea/hypopnea index (AHI), neck circumference, waist circumference, and percentage of exhaled breath at the time of 0.2 seconds (V0.2) sitting and lying down. The V0.2 pre-HD in sitting position presented a correlation with pre-AHI (p = 0.047, r = -0.953) and post-HD (p = 0.010; r = -0.990). In addition, V0.2 post-HD showed a correlation with AHI post-HD (p = 0.029; r = -0.971). Conclusion: The NEP test was promising for clinical use, because it has a rapid application and presents information relevant to the collapse of the airway of ESRD patients with suspected OSA.