Circulating P-Selectin Glycoprotein Ligand 1 and P-Selectin Levels in Obstructive Sleep Apnea Patients.

PURPOSE: Obstructive sleep apnea (OSA) is characterized by chronic intermittent hypoxia which induces inflammation in blood vessels leading to the development of cardiovascular comorbidities. Several studies implicated the role of P-selectin in vascular inflammation of OSA. P-selectin glycoprotein ligand 1 (PSGL-1) is the main activator for P-selectin and is involved in immune cell trafficking. However, PSGL-1 has not been analyzed in OSA. The aim of the study was to investigate plasma PSGL-1 and P-selectin levels to have a deeper understanding on their interaction in obstructive sleep apnea. METHODS: Fifty-one untreated patients with OSA and 42 non-OSA controls were recruited. Plasma PSGL-1 levels were determined in evening and morning samples, P-selectin levels were analyzed in morning samples using commercially available ELISA kits. Polysomnography was performed in all participants. OSA was defined by an apnea-hypopnea index ≥ 5/h. RESULTS: PSGL-1 levels did not differ between controls and OSA patients either in the evening or in the morning. Although, there was no difference between controls (16.9/6.8-40.8 ng/ml) and patients with OSA (19.6/8.4-56.8, p = 0.24), patients with severe OSA had increased plasma P-selectin levels (25.6/8.4-56.8 ng/ml) compared to mild OSA patients (14.1/8.5-35.3 ng/ml, p = 0.006) and controls (p = 0.03). CONCLUSIONS: P-selectin expression relates to disease severity suggesting a pathophysiological role in endothelial cell activation. PSGL-1 levels are unaltered in OSA, suggesting an alternative activation pathway for P-selectin in OSA.

Severe mixed sleep apnea after bilateral lung transplantation in a cystic fibrosis patient: a case report.

BACKGROUND: Lung transplantation is the only treatment for end-stage lung disease in selected patients. After lung transplantation, patient recovery is often slow owing to severe underlying diseases in the patient producing hypoxemia before, during, and after surgery, as well as infections and rejection episodes. Postoperative breathing and ventillatory disorders are also associated with diaphragmatic dysfunction and/or phrenic nerve damage. METHODS: Herein we have reported a case of a 35-year-old man undergoing bilateral lung transplantation owing to worsening of chronic respiratory failure from cystic fibrosis. After uncomplicated surgery, weaning was delayed due to nighttime dyspnea and hypoxemia attributed to diaphragm dysfunction. After improvement of diaphragm function, the symptoms persisted, requiring noninvasive nocturnal ventilatory support. Polysomnography confirmed severe mixed sleep apnea. RESULTS: Effective treatment with noninvasive bi-level positive airway pressure spontaneous/timed mode (BiPAP S/T) ventilation during the nights rendered the patient symptom free. Polysomnography confirmed successful treatment. CONCLUSION: Disordered breathing while sleeping is common after solid organ transplantation. BiPAP S/T ventilator therapy was effective to the treat dominantly central sleep apnea in our patient.