ABSTRACT
INTRODUCTION SARS-CoV-2 infection can produce endothelial injury and microvascular damage, one cause of the multiorgan failure associated with COVID-19. Cerebrovascular endothelial damage increases the risk of stroke in COVID-19 patients, which makes prompt diagnosis important. Endothelial dysfunction can be evaluated by using transcranial Doppler ultrasound to study cerebral hemodynamic reserve, but there are few of these studies in patients with COVID-19, and the technique is not included in COVID-19 action and follow-up guidelines nationally or internationally.
OBJECTIVE Estimate baseline cerebral hemodynamic patterns, cerebral hemodynamic reserve, and breath-holding index in recovered COVID-19 patients.
METHOD We conducted an exploratory study in 51 people; 27 men and 24 women 20–78 years of age, divided into two groups. One group comprised 25 recovered COVID-19 patients, following clinical and epidemiological discharge, who suffered differing degrees of disease severity, and who had no neurological symptoms or disease at the time they were incorporated into the study. The second group comprised 26 people who had not been diagnosed with COVID-19 and who tested negative by RT-PCR at the time of study enrollment. Recovered patients were further divided into two groups: those who had been asymptomatic or had mild disease, and those who had severe or critical disease. We performed transcranial Doppler ultrasounds to obtain baseline and post-apnea tests of cerebral hemodynamic patterns to evaluate cerebral hemodynamic reserve and breath-holding indices. We characterized the recovered patient group and the control group through simple descriptive statistics (means and standard deviations).
RESULTS There were no measurable differences in baseline cerebral hemodynamics between the groups. However, cerebral hemodynamic reserve and breath-holding index were lower in those who had COVID-19 than among control participants (19.9% vs. 36.8% and 0.7 vs. 1.2 respectively). These variables were similar for patients who had asymptomatic or mild disease (19.9% vs.19.8%) and for those who had severe or critical disease (0.7 vs. 0.7).
CONCLUSIONS Patients recovered from SARS-CoV-2 infection showed decreased cerebral hemodynamic reserve and breath-holding index regardless of the disease’s clinical severity or presence of neurological symptoms. These abnormalities may be associated with endothelial damage caused by COVID-19. It would be useful to include transcranial Doppler ultrasound in evaluation and follow-up protocols for patients with COVID-19.
Keywords: SARS-CoV-2; COVID-19; breath holding; ultrasonography, Doppler, transcranial; endothelium, vascular; cerebrovascular circulation; Cuba
INTRODUCTION Continuous venovenous hemodiafiltration, generally used in patients with acute renal failure, enables elimination of humoral mediators of systemic inflammatory response and sepsis from blood. This effect should improve treatment results in patients with multiple organ dysfunction, but evidence of improved survival is insufficient.
OBJECTIVES Describe the effect of continuous venovenous hemodiaflitration on patients with multiple organ dysfunction syndrome in terms of systemic and brain hemodynamics, oxygenation, metabolism and status on ICU separation.
METHODS An observational case series was done of 18 patients (11 men and 7 women) aged 24–78 years with multiple organ dysfunction syndrome treated with continuous venovenous hemodiafiltration in the Medical-Surgical Research Center’s ICU in Havana. General, systemic and brain hemodynamic, oxygenation and metabolic variables were assessed immediately before and 12 hours after starting the procedure; vital status on separation from intensive care was recorded. For analysis, patients were grouped by whether cause of multiple organ dysfunction syndrome was septic or nonseptic. Variable means before and after treatment were compared using the Wilcoxon matched pairs test. Standardized mortality ratios were calculated for both groups, with survival efficacy defined by a ratio of <0.9.
RESULTS After 12 hours continuous venovenous hemodiafitration, the septic group showed clinical improvement, with statistically significant improvement in all variables except mean arterial pressure and brain hemodynamics. Survival to discharge from ICU was 64%, with a standardized mortality ratio of 0.66. In the nonseptic group, survival was 0% and ratio was 2.13; temperature was the only variable found to improve significantly.
CONCLUSIONS Continuous venovenous hemodiafltration improved clinical parameters and survival in patients with multiple organ dysfunction of septic origin. Further studies are needed with larger numbers of patients to corroborate these results.
KEYWORDS Continuous renal replacement therapy, hemodiafiltration, multiple organ failure, septic shock, acute liver failure, MODS, Cuba
