ObjectiveDevelop and validate models that predict mortality of patients diagnosed with COVID-19 admitted to the hospital.DesignRetrospective cohort study.SettingA multicentre cohort across 10 Dutch ...hospitals including patients from 27 February to 8 June 2020.ParticipantsSARS-CoV-2 positive patients (age ≥18) admitted to the hospital.Main outcome measures21-day all-cause mortality evaluated by the area under the receiver operator curve (AUC), sensitivity, specificity, positive predictive value and negative predictive value. The predictive value of age was explored by comparison with age-based rules used in practice and by excluding age from the analysis.Results2273 patients were included, of whom 516 had died or discharged to palliative care within 21 days after admission. Five feature sets, including premorbid, clinical presentation and laboratory and radiology values, were derived from 80 features. Additionally, an Analysis of Variance (ANOVA)-based data-driven feature selection selected the 10 features with the highest F values: age, number of home medications, urea nitrogen, lactate dehydrogenase, albumin, oxygen saturation (%), oxygen saturation is measured on room air, oxygen saturation is measured on oxygen therapy, blood gas pH and history of chronic cardiac disease. A linear logistic regression and non-linear tree-based gradient boosting algorithm fitted the data with an AUC of 0.81 (95% CI 0.77 to 0.85) and 0.82 (0.79 to 0.85), respectively, using the 10 selected features. Both models outperformed age-based decision rules used in practice (AUC of 0.69, 0.65 to 0.74 for age >70). Furthermore, performance remained stable when excluding age as predictor (AUC of 0.78, 0.75 to 0.81).ConclusionBoth models showed good performance and had better test characteristics than age-based decision rules, using 10 admission features readily available in Dutch hospitals. The models hold promise to aid decision-making during a hospital bed shortage.
There is uncertainty whether bilateral near infrared spectroscopy (NIRS) can be used for monitoring of patients with acute stroke.
The NIRS responsiveness to systemic and stroke-related changes was ...studied overnight by assessing the effects of brief peripheral arterial oxygenation and mean arterial pressure alterations in the affected versus nonaffected hemisphere in 9 patients with acute stroke.
Significantly more NIRS drops were registered in the affected compared with the nonaffected hemisphere (477 drops versus 184, P<0.001). In the affected hemispheres, nearly all peripheral arterial oxygenation drops (n=128; 96%) were detected by NIRS; in the nonaffected hemispheres only 23% (n=30; P=0.17). Only a few mean arterial pressure drops were followed by a significant NIRS drop. This was however significantly different between both hemispheres (32% versus 13%, P=0.01).
This pilot study found good responsiveness of NIRS signal to systemic and stroke-related changes at the bedside but requires confirmation in a larger sample.
Cerebral perfusion may be altered in sepsis patients. However, there are conflicting findings on cerebral autoregulation (CA) in healthy participants undergoing the experimental endotoxemia protocol, ...a proxy for systemic inflammation in sepsis. In the current study, a newly developed near-infrared spectroscopy (NIRS)-based CA index is investigated in an endotoxemia study population, together with an index of focal cerebral oxygenation.
Methods:
Continuous-wave NIRS data were obtained from 11 healthy participants receiving a continuous infusion of bacterial endotoxin for 3 h (
ClinicalTrials.gov
NCT02922673) under extensive physiological monitoring. Oxygenated–deoxygenated hemoglobin phase differences in the (very)low frequency (VLF/LF) bands and the Tissue Saturation Index (TSI) were calculated at baseline, during systemic inflammation, and at the end of the experiment 7 h after the initiation of endotoxin administration.
Results:
The median (inter-quartile range) LF phase difference was 16.2° (3.0–52.6°) at baseline and decreased to 3.9° (2.0–8.8°) at systemic inflammation (
p
= 0.03). The LF phase difference increased from systemic inflammation to 27.6° (12.7–67.5°) at the end of the experiment (
p
= 0.005). No significant changes in VLF phase difference were observed. The TSI (mean ± SD) increased from 63.7 ± 3.4% at baseline to 66.5 ± 2.8% during systemic inflammation (
p
= 0.03) and remained higher at the end of the experiment (67.1 ± 4.2%,
p
= 0.04). Further analysis did not reveal a major influence of changes in several covariates such as blood pressure, heart rate, PaCO
2
, and temperature, although some degree of interaction could not be excluded.
Discussion:
A reversible decrease in NIRS-derived cerebral autoregulation phase difference was seen after endotoxin infusion, with a small, sustained increase in TSI. These findings suggest that endotoxin administration in healthy participants reversibly impairs CA, accompanied by sustained microvascular vasodilation.
Background
Cerebral autoregulation is increasingly recognized as a factor that requires evaluation when managing poor grade aneurysmal subarachnoïdal hemorrhage (aSAH) patients. In this single center ...pilot study, we investigated whether intraventricular intracranial pressure (ICP) derived when extraventricular drain (EVD) is open can be used to calculate dynamic autoregulation estimates in ICU aSAH patients.
Methods
Ten patients with the diagnosis of aSAH as confirmed by computed tomography (CT) and CT-angiography were enrolled. ICP was monitored via a transducer connected to the most proximal side exit of the EVD catheter. From at least 30 min periods of brain monitoring before, during, and after temporarily EVD closure, commonly used indexes of dynamic cerebral autoregulation were calculated.
Results
Preserved pulsatile ICP signals were seen with open EVD. There were no significant changes in parameters describing cerebral autoregulation between EVD open and closed conditions. Power spectra of ABP and ICP showed no significant changes for the selected frequency ranges. There was a small significant increase in absolute ICP 2.4 (3.8) mmHg,
p
< 0.001 upon short-term EVD closure. Cerebral spinal reserve capacity (RAP index) worsened significantly by short-term EVD closure.
Conclusions
Due to preserved slow fluctuations in the ICP signal, an open EVD system can be used to calculate dynamic autoregulation indices in aSAH patients requiring intensive care monitoring with the pressure measurement from the most proximal part of drain. If these results are confirmed in larger study, this technique can open the way for investigating the role of autoregulation disturbance in aSAH patients.
Impairments in cerebral autoregulation (CA) are related to poor clinical outcome. Near infrared spectroscopy (NIRS) is a non-invasive technique applied to estimate CA. Our general purpose was to ...study the clinical feasibility of a previously published ‘NIRS-only’ CA methodology in a critically ill intensive care unit (ICU) population and determine its relationship with clinical outcome. Bilateral NIRS measurements were performed for 1–2 h. Data segments of ten-minutes were used to calculate transfer function analyses (TFA) CA estimates between high frequency oxyhemoglobin (oxyHb) and deoxyhemoglobin (deoxyHb) signals. The phase shift was corrected for serial time shifts. Criteria were defined to select TFA phase plot segments (segments) with ‘high-pass filter’ characteristics. In 54 patients, 490 out of 729 segments were automatically selected (67%). In 34 primary neurology patients the median (q1–q3) low frequency (LF) phase shift was higher in 19 survivors compared to 15 non-survivors (13° (6.3–35) versus 0.83° (−2.8–13), p = 0.0167). CA estimation using the NIRS-only methodology seems feasible in an ICU population using segment selection for more robust and consistent CA estimations. The ‘NIRS-only’ methodology needs further validation, but has the advantage of being non-invasive without the need for arterial blood pressure monitoring.
Neurological complications in COVID-19 patients admitted to an intensive care unit (ICU) have been previously reported. As the pandemic progressed, therapeutic strategies were tailored to new ...insights. This study describes the incidence, outcome, and types of reported neurological complications in invasively mechanically ventilated (IMV) COVID-19 patients in relation to three periods during the pandemic.
IMV COVID-19 ICU patients from the Dutch Maastricht Intensive Care COVID (MaastrICCht) cohort were included in a single-center study (March 2020 – October 2021). Demographic, clinical, and follow-up data were collected. Electronic medical records were screened for neurological complications during hospitalization. Three distinct periods (P1, P2, P3) were defined, corresponding to periods with high hospitalization rates. ICU survivors with and without reported neurological complications were compared in an exploratory analysis.
IMV COVID-19 ICU patients (n=324; median age 64 IQR 57–72 years; 238 males (73.5%)) were stratified into P1 (n=94), P2 (n=138), and P3 (n=92). ICU mortality did not significantly change over time (P1=38.3%; P2=41.3%; P3=37.0%; p=.787). The incidence of reported neurological complications during ICU admission gradually decreased over the periods (P1=29.8%; P2=24.6%; P3=18.5%; p=.028). Encephalopathy/delirium (48/324 (14.8%)) and ICU-acquired weakness (32/324 (9.9%)) were most frequently reported and associated with ICU treatment intensity. ICU survivors with neurological complications (n=53) were older (p=.025), predominantly male (p=.037), and had a longer duration of IMV (p<.001) and ICU stay (p<.001), compared to survivors without neurological complications (n=132). A multivariable analysis revealed that only age was independently associated with the occurrence of neurological complications (ORadj=1.0541; 95% CI=1.0171–1.0925; p=.004). Health-related quality-of-life at follow-up was not significantly different between survivors with and without neurological complications (n = 82, p=.054).
A high but decreasing incidence of neurological complications was reported during three consecutive COVID-19 periods in IMV COVID-19 patients. Neurological complications were related to the intensity of ICU support and treatment, and associated with prolonged ICU stay, but did not lead to significantly worse reported health-related quality-of-life at follow-up.
•Neurological complications are common in mechanically ventilated COVID-19 patients.•The most common neurological complications are delirium and ICU-acquired weakness.•The incidence of neurological complications was highest early in the pandemic.•Neurological complications were related to the intensity of ICU support/treatment.
Three-component intravoxel incoherent motion (3C-IVIM) imaging with spectral analysis provides a proxy for interstitial fluid (ISF) (e.g., in perivascular spaces (PVS), granting a potential marker ...for altered cerebral clearance. When 3C-IVIM images are acquired with three orthogonal diffusion-sensitizing directions, these are often averaged into the Trace image. This may result in loss of valuable direction-specific information, particularly in PVS-rich regions (basal ganglia (BG) and centrum semiovale (CSO)). This study assessed the dependence of individual diffusion-sensitizing directions to the ISF fraction in PVS-rich regions. Additionally, we explored the value of diffusion direction-specific information on ISF characteristics in distinguishing thirty-one patients with cognitive impairment (CI) (Alzheimer's disease (n = 15) or Mild Cognitive Impairment (n = 16)) from thirty cognitively healthy elderly controls (CON). Multi-b-value diffusion-weighted images were acquired in three orthogonal directions (L-R (left-right), A-P (anterior-posterior) and S-I (superior-inferior)) at 3 T. Voxel-based spectral analysis using non-negative least squares was conducted to independently analyze the L-R, A-P, S-I, and Trace images. 3C-IVIM measures were first compared between diffusion-sensitizing directions and the Trace within the BG using repeated measures ANOVA. Subsequently, the 3C-IVIM measures were compared per direction between the CI and CSO group in the BG and CSO with multivariable linear regression. Our results show that the ISF fraction significantly differs between all diffusion-sensitizing directions and Trace in the BG, with the highest ISF fraction detected using S-I. Solely using S-I, a higher ISF fraction was identified in CI compared to CON in the BG (p = .020) and CSO (p = .046). Thereby, this study found that the measured ISF fraction depends on the acquired diffusion-sensitizing direction, where S-I is most sensitive to detect ISF and differences between CI and CON. The Trace approach is not always sensitive enough to ISF characteristics. Solely acquiring S-I may offer an alternative to reduce scanning time.
Background and purpose
Coronavirus disease 2019 (COVID‐19) affects the brain, leading to long‐term complaints. Studies combining brain abnormalities with objective and subjective consequences are ...lacking. Long‐term structural brain abnormalities, neurological and (neuro)psychological consequences in COVID‐19 patients admitted to the intensive care unit (ICU) or general ward were investigated. The aim was to create a multidisciplinary view on the impact of severe COVID‐19 on functioning and to compare long‐term consequences between ICU and general ward patients.
Methods
This multicentre prospective cohort study assessed brain abnormalities (3 T magnetic resonance imaging), cognitive dysfunction (neuropsychological test battery), neurological symptoms, cognitive complaints, emotional distress and wellbeing (self‐report questionnaires) in ICU and general ward (non‐ICU) survivors.
Results
In al, 101 ICU and 104 non‐ICU patients participated 8–10 months post‐hospital discharge. Significantly more ICU patients exhibited cerebral microbleeds (61% vs. 32%, p < 0.001) and had higher numbers of microbleeds (p < 0.001). No group differences were found in cognitive dysfunction, neurological symptoms, cognitive complaints, emotional distress or wellbeing. The number of microbleeds did not predict cognitive dysfunction. In the complete sample, cognitive screening suggested cognitive dysfunction in 41%, and standard neuropsychological testing showed cognitive dysfunction in 12%; 62% reported ≥3 cognitive complaints. Clinically relevant scores of depression, anxiety and post‐traumatic stress were found in 15%, 19% and 12%, respectively; 28% experienced insomnia and 51% severe fatigue.
Conclusion
Coronavirus disease 2019 ICU survivors had a higher prevalence for microbleeds but not for cognitive dysfunction compared to general ward survivors. Self‐reported symptoms exceeded cognitive dysfunction. Cognitive complaints, neurological symptoms and severe fatigue were frequently reported in both groups, fitting the post‐COVID‐19 syndrome.
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