Alterations of conjunctival glycocalyx and microcirculation in non-septic critically ill patients

• Published in: Microvascular research Vol. 118; pp. 44 - 48
• Main Authors: Pranskunas, Andrius, Tamosuitis, Tomas, Balciuniene, Neringa, Damanskyte, Diana, Sneider, Edvin, Vitkauskiene, Astra, Sirvinskas, Edmundas, Pilvinis, Vidas, Boerma, E. Christiaan
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.07.2018
• Subjects: Aged; Biomarkers - blood; Cardiac Surgical Procedures - adverse effects; Case-Control Studies; Conjunctiva - blood supply; Conjunctival microcirculation; Critical Illness; Critically ill patients; Female; Glycocalyx; Glycocalyx - metabolism; Glycocalyx - pathology; Humans; Incident dark field-imaging; Male; Microcirculation; Microvessels - pathology; Microvessels - physiopathology; Middle Aged; Mouth Mucosa - blood supply; Nervous System Diseases - blood; Nervous System Diseases - pathology; Nervous System Diseases - physiopathology; Prospective Studies; Regional Blood Flow; Sublingual microcirculation; Syndecan-1 - blood; PBR; TVD; Conjunctival microcirculation; Critically ill patients; IDF; Sublingual microcirculation; MFI; Incident dark field-imaging; Glycocalyx; SDF; PPV; ICU; PVD
• ISSN: 0026-2862; 1095-9319; 1095-9319
• DOI: 10.1016/j.mvr.2018.02.004

As of now the relationship between glycocalyx degradation and microcirculatory perfusion abnormalities in non-septic critical ill patients is unclear. In addition, conjunctival sidestream dark field-imaging for the purpose of glycocalyx thickness estimation has never been performed. We aimed to investigate whether changes in glycocalyx thickness in non-septic patients are associated with microcirculatory alterations in conjunctival and sublingual mucosa. In this single-centre prospective observational study, using techniques for direct in-vivo observation of the microcirculation, we performed a single measurement of microcirculatory perfusion parameters and visualized glycocalyx thickness in both ocular conjunctiva and sublingual mucosa in mixed cardio surgical (n = 18) and neurocritical patients (n = 27) and compared these data with age-matched healthy controls (n = 20). In addition we measured systemic syndecan-1 levels. In the sublingual and conjunctival region we observed a significant increase of the perfused boundary region (PBR) in both neuro-critical and cardiac surgical ICU patients, compared to controls. There was a significant increase of syndecan-1 in ICU patients comparing with controls and in cardiac patients comparing with neurological (120.0[71.0–189.6] vs. 18.0[7.2–40.7], p < 0.05). We detected a weak correlation between syndecan-1 and sublingual PBR but no correlations between global glycocalyx damage and conjuctival glycocalyx thickness. We found significantly lower perfused vessel density (PVD) of small vessels in sublingual mucosa in patients after cardiac surgery in comparison with healthy subjects. In neuro-critical, but not cardiac surgery patients conjunctival TVD and PVD of small vessels were found to be significantly lower in comparison with controls. •Side-stream dark field-imaging of the conjunctiva is a suitable method for the evaluation of glycocalyx thickness.•Conjunctival glycocalyx thickness is impaired in non-septic ICU patients.•Conjunctival capillary density correlates with systemic markers of glycocalix shedding.•Conjunctival microcirculatory perfusion abnormalities were present in patients with cerebral pathology.•Sublingual microvascular alterations occured during systemic endothelial damage.