Objective and subjective cognition in survivors of COVID-19 one year after ICU discharge: the role of demographic, clinical, and emotional factors.

BACKGROUND: Intensive Care Unit (ICU) COVID-19 survivors may present long-term cognitive and emotional difficulties after hospital discharge. This study aims to characterize the neuropsychological dysfunction of COVID-19 survivors 12 months after ICU discharge, and to study whether the use of a measure of perceived cognitive deficit allows the detection of objective cognitive impairment. We also explore the relationship between demographic, clinical and emotional factors, and both objective and subjective cognitive deficits. METHODS: Critically ill COVID-19 survivors from two medical ICUs underwent cognitive and emotional assessment one year after discharge. The perception of cognitive deficit and emotional state was screened through self-rated questionnaires (Perceived Deficits Questionnaire, Hospital Anxiety and Depression Scale and Davidson Trauma Scale), and a comprehensive neuropsychological evaluation was carried out. Demographic and clinical data from ICU admission were collected retrospectively. RESULTS: Out of eighty participants included in the final analysis, 31.3% were women, 61.3% received mechanical ventilation and the median age of patients was 60.73 years. Objective cognitive impairment was observed in 30% of COVID-19 survivors. The worst performance was detected in executive functions, processing speed and recognition memory. Almost one in three patients manifested cognitive complaints, and 22.5%, 26.3% and 27.5% reported anxiety, depression and post-traumatic stress disorder (PTSD) symptoms, respectively. No significant differences were found in the perception of cognitive deficit between patients with and without objective cognitive impairment. Gender and PTSD symptomatology were significantly associated with perceived cognitive deficit, and cognitive reserve with objective cognitive impairment. CONCLUSIONS: One-third of COVID-19 survivors suffered objective cognitive impairment with a frontal-subcortical dysfunction 12 months after ICU discharge. Emotional disturbances and perceived cognitive deficits were common. Female gender and PTSD symptoms emerged as predictive factors for perceiving worse cognitive performance. Cognitive reserve emerged as a protective factor for objective cognitive functioning. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04422444; June 9, 2021.

Thenar oxygen saturation (StO2) alterations during a spontaneous breathing trial predict extubation failure.

BACKGROUND: Weaning from mechanical ventilation (MV) is a cardiovascular stress test. Monitoring the regional oxygenation status has shown promising results in predicting the tolerance to spontaneously breathe in the process of weaning from MV. Our aim was to determine whether changes in skeletal muscle oxygen saturation (StO2) measured by near-infrared spectroscopy (NIRS) on the thenar eminence during a vascular occlusion test (VOT) can be used to predict extubation failure from mechanical ventilation. METHODS: We prospectively studied 206 adult patients with acute respiratory failure receiving MV for at least 48 h from a 30-bed mixed ICU, who were deemed ready to wean by their physicians. Patients underwent a 30-min spontaneous breathing trial (SBT), and were extubated according to the local protocol. Continuous StO2 was measured non-invasively on the thenar eminence. A VOT was performed prior to and at 30 min of the SBT (SBT30). The rate of StO2 deoxygenation (DeO2), StO2 reoxygenation (ReO2) rate and StO2 hyperemic response to ischemia (HAUC) were calculated. RESULTS: Thirty-six of the 206 patients (17%) failed their SBT. The remainder 170 patients (83%) were extubated. Twenty-three of these patients (13.5%) needed reinstitution of MV within 24 h. Reintubated patients displayed a lower HAUC at baseline, and higher relative changes in their StO2 deoxygenation rate between baseline and SBT30 (DeO2 Ratio). A logistic regression-derived StO2 score, combining baseline StO2, HAUC and DeO2 ratio, showed an AUC of 0.84 (95% CI 0.74-0.91) for prediction of extubation failure. CONCLUSIONS: Extubation failure was associated to baseline and dynamic StO2 alterations during the SBT. Monitoring StO2-derived parameters might be useful in predicting extubation outcome.

Trends in the incidence and mortality of patients with community-acquired septic shock 2003-2016.

PURPOSE: To evaluate the incidence and mortality of adult patients with community-acquired septic shock (CASS) and the influence of source control (SC) and other risk factors on the outcome. MATERIAL AND METHODS: The study included patients with CASS admitted to the ICU at a university hospital (2003-2016). Multivariate analyses were performed to identify risk factors of ICU mortality. RESULTS: A total of 625 patients were included. The incidence showed an average annual increase of 4.9% and the mortality an average annual decrease of 1.4%. The patients who required SC showed a lower mortality (20.4%) than patients who did not require SC (31.3%) (p = 0.002). However, the evolution in mortality was different: Mortality decreased in patients who did not require SC (from 56.3% to 20%; p = 0.02), but did not differ in those who required SC (from 21.4% to 27.6%; p = 0.43). In the multivariate analysis, severity at admission, age, alcoholism, cirrhosis, ARDS, neutropenia and thrombocytopenia were associated with worse outcome, whereas appropriate antibiotic treatment and adequate SC were independently associated with better survival. CONCLUSIONS: The incidence of CASS increased and the ICU mortality decreased during the study period. The mortality was mainly due to a decrease in mortality in infections not requiring SC.

Central venous-to-arterial carbon dioxide difference combined with arterial-to-venous oxygen content difference is associated with lactate evolution in the hemodynamic resuscitation process in early septic shock.

INTRODUCTION: Since normal or high central venous oxygen saturation (ScvO2) values cannot discriminate if tissue perfusion is adequate, integrating other markers of tissue hypoxia, such as central venous-to-arterial carbon dioxide difference (PcvaCO2 gap) has been proposed. In the present study, we aimed to evaluate the ability of the PcvaCO2 gap and the PcvaCO2/arterial-venous oxygen content difference ratio (PcvaCO2/CavO2) to predict lactate evolution in septic shock. METHODS: Observational study. Septic shock patients within the first 24 hours of ICU admission. After restoration of mean arterial pressure, and central venous oxygen saturation, the PcvaCO2 gap and the PcvaCO2/CavO2 ratio were calculated. Consecutive arterial and central venous blood samples were obtained for each patient within 24 hours. Lactate improvement was defined as the decrease ≥ 10% of the previous lactate value. RESULTS: Thirty-five septic shock patients were studied. At inclusion, the PcvaCO2 gap was 5.6 ± 2.1 mmHg, and the PcvaCO2/CavO2 ratio was 1.6 ± 0.7 mmHg · dL/mL O2. Those patients whose lactate values did not decrease had higher PcvaCO2/CavO2 ratio values at inclusion (1.8 ± 0.8vs. 1.4 ± 0.5, p 0.02). During the follow-up, 97 paired blood samples were obtained. No-improvement in lactate values was associated to higher PcvaCO2/CavO2 ratio values in the previous control. The ROC analysis showed an AUC 0.82 (p < 0.001), and a PcvaCO2/CavO2 ratio cut-off value of 1.4 mmHg · dL/mL O2 showed sensitivity 0.80 and specificity 0.75 for lactate improvement prediction. The odds ratio of an adequate lactate clearance was 0.10 (p < 0.001) in those patients with an elevated PcvaCO2/CavO2 ratio (≥1.4). CONCLUSION: In a population of septic shock patients with normalized MAP and ScvO2, the presence of elevated PcvaCO2/CavO2 ratio significantly reduced the odds of adequate lactate clearance during the following hours.

Thenar oxygen saturation and invasive oxygen delivery measurements in critically ill patients in early septic shock.

This prospective study was aimed to test the hypothesis that tissue hemoglobin oxygen saturation (StO2) measured noninvasively using near-infrared spectroscopy is a reliable indicator of global oxygen delivery (DO2) measured invasively using a pulmonary artery catheter (PAC) in patients with septic shock. The study setting was a 26-bed medical-surgical intensive care unit at a university hospital. Subjects were adult patients in septic shock who required PAC hemodynamic monitoring for resuscitation. Interventions included transient ischemic challenge on the forearm. After blood pressure normalization, hemodynamic and oximetric PAC variables and, simultaneously, steady-state StO2 and its changes from ischemic challenge (deoxygenation and reoxygenation rates) were measured. Fifteen patients were studied. All the patients had a mean arterial pressure above 65 mmHg. The DO2 index (iDO2) range in the studied population was 215 to 674 mL O2/min per m. The mean mixed venous oxygen saturation value was 61% ± 10%, mean cardiac index was 3.4 ± 0.9 L/min per m, and blood lactate level was 4.6 ± 2.7 mmol/L. Steady-state StO2 significantly correlated with iDO2, arterial and venous O2 content, and O2 extraction ratio. A StO2 cutoff value of 75% predicted iDO2 below 450, with a sensitivity of 0.9 and a specificity of 0.9. In patients in septic shock and normalized MAP, low StO2 reflects extremely low iDO2. Steady-state StO2 does not correlate with moderately low iDO2, indicating poor sensitivity of StO2 to rule out hypoperfusion.