Convalescent Plasma Therapy in Late-State, Severe COVID-19 Infection.

OBJECTIVES: Current evidence favors plasma to be effective against coronavirus disease 2019 (COVID-19) in critically ill patients in the early stages of infection. We investigated the safety and efficacy of convalescent plasma in specifically late-stage (designated as after 2 weeks of hospital admission) severe COVID-19 infection. We also conducted a literature review on the late-stage use of plasma in COVID-19. METHODS: This case series examined eight COVID-19 patients admitted to the intensive care unit (ICU) who met criteria for severe or life-threatening complications. Each patient received one dose (200 mL) of plasma. Clinical information was gathered in intervals of 1 day pretransfusion and 1 hour, 3 days, and 7 days posttransfusion. The primary outcome was effectiveness of plasma transfusion, measured by clinical improvement, laboratory parameters, and all-cause mortality. RESULTS: Eight ICU patients received plasma late in the course of COVID-19 infection, on average at 16.13 days postadmission. On the day before transfusion, the averaged initial Sequential Organ Failure Assessment (SOFA) score, PaO2:FiO2 ratio, Glasgow Coma Scale (GCS), and lymphocyte count were 6.5, 228.03, 8.63, and 1.19, respectively. Three days after plasma treatment, the group averages for the SOFA score (4.86), PaO2:FiO2 ratio (302.73), GCS (9.29), and lymphocyte count (1.75) improved. Although the mean GCS improved to 10.14 by posttransfusion day 7, the other means marginally worsened with an SOFA score of 5.43, a PaO2:FiO2 ratio of 280.44, and a lymphocyte count of 1.71. Clinical improvement was noted in six patients who were discharged from the ICU. CONCLUSIONS: This case series provides evidence that convalescent plasma may be safe and effective in late-stage, severe COVID-19 infection. Results showed clinical improvement posttransfusion as well as decreased all-cause mortality in comparison to pretransfusion predicted mortality. Randomized controlled trials are needed to conclusively determine benefits, dosage, and timing of treatment.

Conjunctival Vessels in Diabetes Using Functional Slit Lamp Biomicroscopy.

PURPOSE: This study used functional slit lamp biomicroscopy (FSLB) to quantify conjunctival microvessel parameters in individuals with and without diabetes and examined whether these metrics could be used as surrogate markers of diabetes-related complications. METHODS: A cross-sectional study of 98 controls (C), 13 individuals with diabetes without complications (D-C), and 21 with diabetes and related complications (D+C), which included retinopathy, nephropathy, neuropathy, and cardiovascular-, peripheral vascular-, and cerebrovascular diseases, was performed. Bulbar conjunctival metrics (venule diameter, length, axial velocity [Va], cross-sectional velocity [Vs], flow [Q], and branching complexity) were measured using FSLB (digital camera mounted on traditional slit lamp). RESULTS: The mean age was 60 ± 11 years, and demographics were similar across the groups. Va and Vs significantly differed between groups. Va was 0.51 ± 0.17 mm/s, 0.62 ± 0.17 mm/s, and 0.45 ± 0.17 mm/s in the C, D-C, and D+C groups, respectively (P = 0.025). Similarly, Vs was 0.35 ± 01.12, 0.43 ± 0.13, and 0.32 ± 0.13 mm/s in the C, D-C, and D+C groups, respectively (P = 0.031). Black individuals had increased Va, Vs, and Q compared with White individuals (P < 0.05), but differences in velocities persisted after accounting for race. Among patients with diabetes, Va and Vs correlated with number of organ systems affected (Va: ρ = -0.42, P = 0.016; Vs: ρ = -0.41, P = 0.021). Va, Vs, and Q significantly (P ≤ 0.005) discriminated between diabetic patients with and without complications (area under the receiver operating curve for Va = 0.81, Vs = 0.79, Q = 0.81). CONCLUSIONS: Bulbar conjunctival blood flow metrics measured by FSLB differed between controls, diabetic patients without complications, and diabetic patients with complications. FSLB is a quick, easily accessible, and noninvasive alternative that might estimate the burden of vascular complications in diabetes.

Functional slit lamp biomicroscopy metrics correlate with cardiovascular risk.

PURPOSE: Our aim was to correlate cardiovascular risk factor estimation with bulbar conjunctival blood flow metrics as measured through Functional Slit Lamp Biomicroscopy (FSLB). METHODS: Cross-sectional study of individuals with otherwise healthy eyelid and corneal anatomy recruited from the Miami Veterans Affairs (VA) Healthcare System eye clinic. We measured conjunctival microvascular hemodynamics by mounting a camera on a slit lamp and cardiovascular risk using the Framingham risk score. Our main outcome measures were correlations between conjunctival vessel parameters (axial and cross-sectional blood flow velocity, blood flow rate) and Framingham score. RESULTS: We included 84 patients who underwent FSLB. The mean age was 60 years, the majority were male (88%) and approximately half the patients were black (54%). Mean vessel diameter was similar between all Framingham score categories. Axial and cross-sectional blood flow velocities and blood flow rate were lower in individuals with higher Framingham risk score. Specifically, mean cross-sectional blood flow velocity in individuals with a low Framingham risk score was 0.37 ±â€¯0.0.9 mm/s, with an intermediate score was 0.30 ±â€¯0.09 mm/s, and with a high score was 0.29 ±â€¯0.10 mm/s, p = 0.04. Mean blood flow rate in individuals with a low Framingham risk score was 133.4 ±â€¯59.6 pl/s, with an intermediate score was 123.6 ±â€¯39.3 pl/s, and with a high score was 121.9 ±â€¯52.6 pl/s, p = 0.04. The beta coefficient of the blood flow rate for change in Framingham score was -0.73; 95% CI-1.34-0.13, p = 0.02, adjusted for race. CONCLUSION: FSLB correlates with cardiovascular risk estimation. Future studies should evaluate if FSLB can predict cardiovascular outcomes.