Neurological Complications and Noninvasive Multimodal Neuromonitoring in Critically Ill Mechanically Ventilated COVID-19 Patients

Stroke in critically ill patients with respiratory failure due to COVID-19: Disparities between low-middle and high-income countries

PURPOSE

We aimed to compare the incidence of stroke in low-and middle-income countries (LMICs) versus high-income countries (HICs) in critically ill patients with COVID-19 and its impact on in-hospital mortality.

METHODS

International observational study conducted in 43 countries. Stroke and mortality incidence rates and rate ratios (IRR) were calculated per admitted days using Poisson regression. Inverse probability weighting (IPW) was used to address the HICs vs. LMICs imbalance for confounders.

RESULTS

23,738 patients [20,511(86.4 %) HICs vs. 3,227(13.6 %) LMICs] were included. The incidence stroke/1000 admitted-days was 35.7 (95 %CI = 28.4-44.9) LMICs and 17.6 (95 %CI = 15.8-19.7) HICs; ischemic 9.47 (95 %CI = 6.57-13.7) LMICs, 1.97 (95 %CI = 1.53, 2.55) HICs; hemorrhagic, 7.18 (95 %CI = 4.73-10.9) LMICs, and 2.52 (95 %CI = 2.00-3.16) HICs; unspecified stroke type 11.6 (95 %CI = 7.75-17.3) LMICs, 8.99 (95 %CI = 7.70-10.5) HICs. In regression with IPW, LMICs vs. HICs had IRR = 1.78 (95 %CI = 1.31-2.42, p < 0.001). Patients from LMICs were more likely to die than those from HICs [43.6% vs 29.2 %; Relative Risk (RR) = 2.59 (95 %CI = 2.29-2.93), p < 0.001)]. Patients with stroke were more likely to die than those without stroke [RR = 1.43 (95 %CI = 1.19-1.72), p < 0.001)].

CONCLUSIONS

Stroke incidence was low in HICs and LMICs although the stroke risk was higher in LMICs. Both LMIC status and stroke increased the risk of death. Improving early diagnosis of stroke and redistribution of healthcare resources should be a priority.

TRIAL REGISTRATION

ACTRN12620000421932 registered on 30/03/2020.

The incidence of neurological complications in mechanically ventilated COVID-19 ICU patients: An observational single-center cohort study in three COVID-19 periods

BACKGROUND

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Cerebral hemodynamics and optic nerve sheath diameter acquired via neurosonology in critical patients with severe coronavirus disease: experience of a national referral hospital in Peru

Aim

We aimed to describe the neurosonological findings related to cerebral hemodynamics acquired using transcranial Doppler and to determine the frequency of elevated ICP by optic nerve sheath diameter (ONSD) measurement in patients with severe coronavirus disease (COVID-19) hospitalized in the intensive care unit of a national referral hospital in Peru.

Methods

We included a retrospective cohort of adult patients hospitalized with severe COVID-19 and acute respiratory failure within the first 7 days of mechanical ventilation under deep sedoanalgesia, with or without neuromuscular blockade who underwent ocular ultrasound and transcranial Doppler. We determine the frequency of elevated ICP by measuring the diameter of the optic nerve sheath, choosing as best cut-off value a diameter equal to or >5.8 mm. We also determine the frequency of sonographic patterns obtained by transcranial Doppler. Through insonation of the middle cerebral artery. Likewise, we evaluated the associations of clinical, mechanical ventilator, and arterial blood gas variables with ONSD ≥5.8 mm and pulsatility index (PI) ≥1.1. We also evaluated the associations of hemodynamic findings and ONSD with mortality the effect size was estimated using Poisson regression models with robust variance.

Results

This study included 142 patients. The mean age was 51.39 ± 13.3 years, and 78.9% of patients were male. Vasopressors were used in 45.1% of patients, and mean arterial pressure was 81.87 ± 10.64 mmHg. The mean partial pressure of carbon dioxide (PaCO2) was elevated (54.08 ± 16.01 mmHg). Elevated intracranial pressure was seen in 83.1% of patients, as estimated based on ONSD ≥5.8 mm. A mortality rate of 16.2% was reported. In the multivariate analysis, age was associated with elevated ONSD (risk ratio [RR] = 1.07). PaCO2 was a protective factor (RR = 0.64) in the cases of PI ≥ 1.1. In the mortality analysis, the mean velocity was a risk factor for mortality (RR = 1.15).

Conclusions

A high rate of intracranial hypertension was reported, with ONSD measurement being the most reliable method for estimation. The increase in ICP measured by ONSD in patients with severe COVID-19 on mechanical ventilation is not associated to hypercapnia or elevated intrathoracic pressures derived from protective mechanical ventilation.

Long-term outcomes of hospitalized patients with SARS-CoV-2/COVID-19 with and without neurological involvement: 3-year follow-up assessment

BACKGROUND

Acute neurological manifestation is a common complication of acute Coronavirus Disease 2019 (COVID-19) disease. This retrospective cohort study investigated the 3-year outcomes of patients with and without significant neurological manifestations during initial COVID-19 hospitalization.

METHODS AND FINDINGS

Patients hospitalized for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection between 03/01/2020 and 4/16/2020 in the Montefiore Health System in the Bronx, an epicenter of the early pandemic, were included. Follow-up data was captured up to 01/23/2023 (3 years post-COVID-19). This cohort consisted of 414 patients with COVID-19 with significant neurological manifestations and 1,199 propensity-matched patients (for age and COVID-19 severity score) with COVID-19 without neurological manifestations. Neurological involvement during the acute phase included acute stroke, new or recrudescent seizures, anatomic brain lesions, presence of altered mentation with evidence for impaired cognition or arousal, and neuro-COVID-19 complex (headache, anosmia, ageusia, chemesthesis, vertigo, presyncope, paresthesias, cranial nerve abnormalities, ataxia, dysautonomia, and skeletal muscle injury with normal orientation and arousal signs). There were no significant group differences in female sex composition (44.93% versus 48.21%, p = 0.249), ICU and IMV status, white, not Hispanic (6.52% versus 7.84%, p = 0.380), and Hispanic (33.57% versus 38.20%, p = 0.093), except black non-Hispanic (42.51% versus 36.03%, p = 0.019). Primary outcomes were mortality, stroke, heart attack, major adverse cardiovascular events (MACE), reinfection, and hospital readmission post-discharge. Secondary outcomes were neuroimaging findings (hemorrhage, active and prior stroke, mass effect, microhemorrhages, white matter changes, microvascular disease (MVD), and volume loss). More patients in the neurological cohort were discharged to acute rehabilitation (10.39% versus 3.34%, p < 0.001) or skilled nursing facilities (35.75% versus 25.35%, p < 0.001) and fewer to home (50.24% versus 66.64%, p < 0.001) than matched controls. Incidence of readmission for any reason (65.70% versus 60.72%, p = 0.036), stroke (6.28% versus 2.34%, p < 0.001), and MACE (20.53% versus 16.51%, p = 0.032) was higher in the neurological cohort post-discharge. Per Kaplan-Meier univariate survival curve analysis, such patients in the neurological cohort were more likely to die post-discharge compared to controls (hazard ratio: 2.346, (95% confidence interval (CI) [1.586, 3.470]; p < 0.001)). Across both cohorts, the major causes of death post-discharge were heart disease (13.79% neurological, 15.38% control), sepsis (8.63%, 17.58%), influenza and pneumonia (13.79%, 9.89%), COVID-19 (10.34%, 7.69%), and acute respiratory distress syndrome (ARDS) (10.34%, 6.59%). Factors associated with mortality after leaving the hospital involved the neurological cohort (odds ratio (OR): 1.802 (95% CI [1.237, 2.608]; p = 0.002)), discharge disposition (OR: 1.508 (95% CI [1.276, 1.775]; p < 0.001)), congestive heart failure (OR: 2.281 (95% CI [1.429, 3.593]; p < 0.001)), higher COVID-19 severity score (OR: 1.177 (95% CI [1.062, 1.304]; p = 0.002)), and older age (OR: 1.027 (95% CI [1.010, 1.044]; p = 0.002)). There were no group differences in radiological findings, except that the neurological cohort showed significantly more age-adjusted brain volume loss (p = 0.045) than controls. The study's patient cohort was limited to patients infected with COVID-19 during the first wave of the pandemic, when hospitals were overburdened, vaccines were not yet available, and treatments were limited. Patient profiles might differ when interrogating subsequent waves.

CONCLUSIONS

Patients with COVID-19 with neurological manifestations had worse long-term outcomes compared to matched controls. These findings raise awareness and the need for closer monitoring and timely interventions for patients with COVID-19 with neurological manifestations, as their disease course involving initial neurological manifestations is associated with enhanced morbidity and mortality.

Derivation and validation of a quantitative risk prediction model for weaning and extubation in neurocritical patients

Background

Patients with severe neurological conditions are at high risk during withdrawal and extubation, so it is important to establish a model that can quantitatively predict the risk of this procedure.

Methods

By analyzing the data of patients with traumatic brain injury and tracheal intubation in the ICU of the affiliated hospital of Hangzhou Normal University, a total of 200 patients were included, of which 140 were in the modeling group and 60 were in the validation group. Through binary logistic regression analysis, 8 independent risk factors closely related to the success of extubation were screened out, including age ≥ 65 years old, APACHE II score ≥ 15 points, combined chronic pulmonary disease, GCS score < 8 points, oxygenation index <300, cough reflex, sputum suction frequency, and swallowing function.

Results

Based on these factors, a risk prediction scoring model for extubation was constructed with a critical value of 18 points. The AUC of the model was 0.832, the overall prediction accuracy was 81.5%, the specificity was 81.6%, and the sensitivity was 84.1%. The data of the validation group showed that the AUC of the model was 0.763, the overall prediction accuracy was 79.8%, the specificity was 84.8%, and the sensitivity was 64.0%.

Conclusion

These results suggest that the extubation risk prediction model constructed through quantitative scoring has good predictive accuracy and can provide a scientific basis for clinical practice, helping to assess and predict extubation risk, thereby improving the success rate of extubation and improving patient prognosis.

The Use of Noninvasive Multimodal Neuromonitoring in Adult Critically Ill Patients With COVID-19 Infection

INTRODUCTION

Noninvasive neuromonitoring could be a valuable option for bedside assessment of cerebral dysfunction in patients with coronavirus disease-2019 (COVID-19) admitted to intensive care units (ICUs). This systematic review aims to investigate the use of noninvasive multimodal neuromonitoring in critically ill adult patients with COVID-19 infection.

METHODS

MEDLINE/PubMed, Scopus, Cochrane, and EMBASE databases were searched for studies investigating noninvasive neuromonitoring in patients with COVID-19 admitted to ICUs. The monitoring included transcranial Doppler ultrasonography (TCD), the Brain4care Corp. cerebral compliance monitor (B4C), optic nerve sheath diameter (ONSD), near infrared spectroscopy, automated pupillometry, and electroencephalography (EEG).

RESULTS

Thirty-two studies that investigated noninvasive neuromonitoring techniques in patients with COVID-19 in the ICU were identified from a systematic search of 7001 articles: 1 study investigating TCD, ONSD and pupillometry; 2 studies investigating the B4C device and TCD; 3 studies investigating near infrared spectroscopy and TCD; 4 studies investigating TCD; 1 case series investigating pupillometry, and 21 studies investigating EEG. One hundred and nineteen patients underwent TCD monitoring, 47 pupillometry, 49 ONSD assessment, 50 compliance monitoring with the B4C device, and 900 EEG monitoring. Alterations in cerebral hemodynamics, brain compliance, brain oxygenation, pupillary response, and brain electrophysiological activity were common in patients with COVID-19 admitted to the ICU; these abnormalities were not clearly associated with worse outcome or the development of new neurological complications.

CONCLUSIONS

The use of noninvasive multimodal neuromonitoring in critically ill COVID-19 patients could be considered to facilitate the detection of neurological derangements. Determining whether such findings allow earlier detection of neurological complications or guide appropriate therapy requires additional studies.

Neurological complications and effects of COVID-19: Symptoms and conceivable mechanisms

A novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in December 2019 in Wuhan, China. The new coronavirus disease (COVID-19) was declared a global pandemic by the World Health Organization (WHO) in March 2020. SARS-CoV-2 can invade the nervous system aside from infecting the respiratory system as its primary target. The most common nervous system symptoms of COVID-19 are stated as headache, myalgia, fatigue, nausea, vomiting, sudden and unexplained anosmia, and ageusia. More severe conditions such as encephalomyelitis, acute myelitis, thromboembolic events, ischemic stroke, intracerebral hemorrhage, Guillain-Barré-syndrome, Bell's palsy, rhabdomyolysis, and even coma have also been reported. Cohort studies revealed that neurological findings are associated with higher morbidity and mortality. The neurological symptoms and manifestations caused by SARS-CoV-2 and COVID-19 are examined and summarized in this article.

Neurological manifestations of COVID-19: a systematic review and detailed comprehension

The current pandemic caused by severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) is accompanied with a rapid increase of reports and papers detailing its neurological effects and symptoms. The virus infection causes respiratory illness named by the world health organization as corona virus 19 (COVID-19).This systematic review aims to study and summarize the different neurological manifestations of this virus. All articles published and indexed via Pubmed, Medline and Google Scholar databases between January 1st 2020 and February 28th 2021 that reported neurological symptoms of SARS-CoV-2 are reviewed following the Preferred Reporting Items for Systemic review and Meta-Analysis (PRISMA) guidelines.We included data from 113 articles: eight prospective studies, 25 retrospective studies and the rest were case reports/series. COVID-19 can present with central nervous system manifestations, such as headache, encephalitis and encephalopathy, peripheral nervous system manifestations, such as anosmia, ageusia and Guillian Barre syndrome, and skeletal muscle manifestations, such as myalgia and myasthenia gravis. Our systematic review showed that COVID-19 can be manifested by a wide spectrum of neurological symptoms reported either in the early stage or within the course of the disease. However, a detailed comprehension of these manifestations is required and more studies are needed in order to improve our scientific knowledge and to develop preventive and therapeutic measures to control this pandemic.

Neurorecovery after Critical COVID-19 Illness

With the hundreds of millions of people worldwide who have been, and continue to be, affected by pandemic coronavirus disease (COVID-19) and its chronic sequelae, strategies to improve recovery and rehabilitation from COVID-19 are critical global public health priorities. Neurologic complications have been associated with acute COVID-19 infection, usually in the setting of critical COVID-19 illness. Neurologic complications are also a core feature of the symptom constellation of long COVID and portend poor outcomes. In this article, we review neurologic complications and their mechanisms in critical COVID-19 illness and long COVID. We focus on parallels with neurologic disease associated with non-COVID critical systemic illness. We conclude with a discussion of how recent findings can guide both neurologists working in post-acute neurologic rehabilitation facilities and policy makers who influence neurologic resource allocation.

The importance of monitoring cerebral oxygenation in non brain injured patients

Over the past few years, the use of non-invasive neuromonitoring in non-brain injured patients has increased, as a result of the recognition that many of these patients are at risk of brain injury in a wide number of clinical scenarios and therefore may benefit from its application which allows interventions to prevent injury and improve outcome. Among these, are post cardiac arrest syndrome, sepsis, liver failure, acute respiratory failure, and the perioperative settings where in the absence of a primary brain injury, certain groups of patients have high risk of neurological complications. While there are many neuromonitoring modalities utilized in brain injured patients, the majority of those are either invasive such as intracranial pressure monitoring, require special skill such as transcranial Doppler ultrasonography, or intermittent such as pupillometry and therefore unable to provide continuous monitoring. Cerebral oximetry using Near infrared Spectroscopy, is a simple non invasive continuous measure of cerebral oxygenation that has been shown to be useful in preventing cerebral hypoxemia both within the intensive care unit and the perioperative settings. At present, current recommendations for standard monitoring during anesthesia or in the general intensive care concentrate mainly on hemodynamic and respiratory monitoring without specific indications regarding the brain, and in particular, brain oximetry. The aim of this manuscript is to provide an up-to-date overview of the pathophysiology and applications of cerebral oxygenation in non brain injured patients as part of non-invasive multimodal neuromonitoring in the early identification and treatment of neurological complications in this population.

Systemic and Cerebral Effects of Physiotherapy in Mechanically Ventilated Subjects

BACKGROUND

Physiotherapy may result in better functional outcomes, shorter duration of delirium, and more ventilator-free days. The effects of physiotherapy on different subpopulations of mechanically ventilated patients on respiratory and cerebral function are still unclear. We evaluated the effect of physiotherapy on systemic gas exchange and hemodynamics as well as on cerebral oxygenation and hemodynamics in mechanically ventilated subjects with and without COVID-19 pneumonia.

METHODS

This was an observational study in critically ill subjects with and without COVID-19 who underwent protocolized physiotherapy (including respiratory and rehabilitation physiotherapy) and neuromonitoring of cerebral oxygenation and hemodynamics. PaO2 /FIO2 , PaCO2 , hemodynamics (mean arterial pressure [MAP], mm Hg; heart rate, beats/min), and cerebral physiologic parameters (noninvasive intracranial pressure, cerebral perfusion pressure using transcranial Doppler, and cerebral oxygenation using near-infrared spectroscopy) were assessed before (T0) and immediately after physiotherapy (T1).

RESULTS

Thirty-one subjects were included (16 with COVID-19 and 15 without COVID-19). Physiotherapy improved PaO2 /FIO2 in the overall population (T1 = 185 [108-259] mm Hg vs T0 = 160 [97-231] mm Hg, P = .02) and in the subjects with COVID-19 (T1 = 119 [89-161] mm Hg vs T0 = 110 [81-154] mm Hg, P = .02) and decreased the PaCO2 in the COVID-19 group only (T1 = 40 [38-44] mm Hg vs T0 = 43 [38-47] mm Hg, P = .03). Physiotherapy did not affect cerebral hemodynamics, whereas increased the arterial oxygen part of hemoglobin both in the overall population (T1 = 3.1% [-1.3 to 4.9] vs T0 = 1.1% [-1.8 to 2.6], P = .007) and in the non-COVID-19 group (T1 = 3.7% [0.5-6.3] vs T0 = 0% [-2.2 to 2.8], P = .02). Heart rate was higher after physiotherapy in the overall population (T1 = 87 [75-96] beats/min vs T0 = 78 [72-92] beats/min, P = .044) and in the COVID-19 group (T1 = 87 [81-98] beats/min vs T0 = 77 [72-91] beats/min, P = .01), whereas MAP increased in the COVID-19 group only (T1 = 87 [82-83] vs T0 = 83 [76-89], P = .030).

CONCLUSIONS

Protocolized physiotherapy improved gas exchange in subjects with COVID-19, whereas it improved cerebral oxygenation in non-COVID-19 subjects.

Morphological and functional findings in COVID-19 lung disease as compared to Pneumonia, ARDS, and High-Altitude Pulmonary Edema

Coronavirus disease-2019 (COVID-19) may severely affect respiratory function and evolve to life-threatening hypoxia. The clinical experience led to the implementation of standardized protocols assuming similarity to severe acute respiratory syndrome (SARS-CoV-2). Understanding the histopathological and functional patterns is essential to better understand the pathophysiology of COVID-19 and then develop new therapeutic strategies. Epithelial and endothelial cell damage can result from the virus attack, thus leading to immune-mediated response. Pulmonary histopathological findings show the presence of Mallory bodies, alveolar coating cells with nuclear atypia, reactive pneumocytes, reparative fibrosis, intra-alveolar hemorrhage, moderate inflammatory infiltrates, micro-abscesses, microthrombus, hyaline membrane fragments, and emphysema-like lung areas. COVID-19 patients may present different respiratory stages from silent to critical hypoxemia, are associated with the degree of pulmonary parenchymal involvement, thus yielding alteration of ventilation and perfusion relationships. This review aims to: discuss the morphological (histopathological and radiological) and functional findings of COVID-19 compared to acute interstitial pneumonia, acute respiratory distress syndrome (ARDS), and high-altitude pulmonary edema (HAPE), four entities that share common clinical traits, but have peculiar pathophysiological features with potential implications to their clinical management.

Optic nerve sheath diameter is associated with outcome in severe Covid-19

Neurological symptoms are common in Covid-19 and cerebral edema has been shown post-mortem. The mechanism behind this is unclear. Elevated intracranial pressure (ICP) has not been extensively studied in Covid-19. ICP can be estimated noninvasively with measurements of the optic nerve sheath diameter (ONSD). We performed a cohort study with ONSD ultrasound measurements in severe cases of Covid-19 at an intensive care unit (ICU). We measured ONSD with ultrasound in adults with severe Covid-19 in the ICU at Karolinska University Hospital in Sweden. Patients were classified as either having normal or elevated ONSD. We compared ICU length of stay (ICU-LOS) and 90 day mortality between the groups. 54 patients were included. 11 of these (20.4%) had elevated ONSD. Patients with elevated ONSD had 12 days longer ICU-LOS (95% CI 2 to 23 p = 0.03) and a risk ratio of 2.3 for ICU-LOS ≥ 30 days. There were no significant differences in baseline data or 90 day mortality between the groups. Elevated ONSD is common in severe Covid-19 and is associated with adverse outcome. This may be caused by elevated ICP. This is a clinically important finding that needs to be considered when deciding upon various treatment strategies.

ARDS associated acute brain injury: from the lung to the brain

A complex interrelation between lung and brain in patients with acute lung injury (ALI) has been established by experimental and clinical studies during the last decades. Although, acute brain injury represents one of the most common insufficiencies in patients with ALI and acute respiratory distress syndrome (ARDS), the underlying pathophysiology of the observed crosstalk remains poorly understood due to its complexity. Specifically, it involves numerous pathophysiological parameters such as hypoxemia, neurological adverse events of lung protective ventilation, hypotension, disruption of the BBB, and neuroinflammation in such a manner that the brain of ARDS patients-especially hippocampus-becomes very vulnerable to develop secondary lung-mediated acute brain injury. A protective ventilator strategy could reduce or even minimize further systemic release of inflammatory mediators and thus maintain brain homeostasis. On the other hand, mechanical ventilation with low tidal volumes may lead to self-inflicted lung injury, hypercapnia and subsequent cerebral vasodilatation, increased cerebral blood flow, and intracranial hypertension. Therefore, by describing the pathophysiology of ARDS-associated acute brain injury we aim to highlight and discuss the possible influence of mechanical ventilation on ALI-associated acute brain injury.

Hospital length of stay for COVID-19 patients: A systematic review and meta-analysis

The length of stay in the hospital for COVID-19 can aid in understanding the disease's prognosis. Thus, the goal of this study was to collectively estimate the hospital length of stay (LoS) in COVID-19 hospitalized individuals. To locate related studies, international databases (including Google Scholar, Science Direct, PubMed, and Scopus) were searched. The I² index, the Cochran Q test, and T² were used to analyze study heterogeneity. The mean LoS in COVID- 19 hospitalized patients was estimated using a random-effects model. COVID-19's total pooled estimated hospital LoS was 15.35, 95%CI:13.47-17.23; p<0.001, I² = 80.0). South America had the highest pooled estimated hospital LoS of COVID-19 among the continents, at 20.85 (95%CI: 14.80-26.91; p<0.001, I² = 0.01), whereas Africa had the lowest at 8.56 8 (95%CI: 1.00-22.76). The >60 age group had the highest pooled estimated COVID-19 hospital LoS of 16.60 (95%CI: 12.94-20.25; p<0.001, I² = 82.6), while the 40 age group had the lowest hospital LoS of 10.15 (95% CI: 4.90-15.39, p<0.001, I² = 22.1). The metanalysis revealed that COVID-19's hospital LoS was more than 10 days. However, it appears that this duration varies depending on a number of factors, including the patient's age and the availability of resources.

Complications of invasive mechanical ventilation in critically Ill Covid-19 patients - A narrative review

Critically ill COVID-19 patients have to undergo positive pressure ventilation, a non-physiological and invasive intervention that can be lifesaving in severe ARDS. Similar to any other intervention, it has its pros and cons. Despite following Lung Protective Ventilation (LPV), some of the complications are frequently reported in these critically ill patients and significantly impact overall mortality. The complications related to invasive mechanical ventilation (IMV) in critically ill COVID-19 patients can be broadly divided into pulmonary and non-pulmonary. Among pulmonary complications, the most frequent is ventilator-associated pneumonia. Others are barotrauma, including subcutaneous emphysema, pneumomediastinum, pneumothorax, bullous lesions, cardiopulmonary effects of right ventricular dysfunction, and pulmonary complications mimicking cardiac failure, including pulmonary edema. Tracheal complications, including full-thickness tracheal lesions (FTTLs) and tracheoesophageal fistulas (TEFs) are serious but rare complications. Non-Pulmonary complications include neurological, nephrological, ocular, and oral complications.

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The complications related to IMV in critically ill covid 19 patients can be broadly divided into pulmonary and non-pulmonary complications.

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Among pulmonary complications the most frequent is Ventilator associated pneumonia.

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Others are Barotrauma, Cardiopulmonary effects of right ventricular dysfunction & Pulmonary complications mimicking cardiac failure including pulmonary edema, tracheal complications including full thickness tracheal lesions & tracheoesophageal fistulas.

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Non-Pulmonary complications of prolonged IMV include neurological, nephrological, ocular and oral complications.

Autonomic Dysfunction during Acute SARS-CoV-2 Infection: A Systematic Review

Although autonomic dysfunction (AD) after the recovery from Coronavirus disease 2019 (COVID-19) has been thoroughly described, few data are available regarding the involvement of the autonomic nervous system (ANS) during the acute phase of SARS-CoV-2 infection. The primary aim of this review was to summarize current knowledge regarding the AD occurring during acute COVID-19. Secondarily, we aimed to clarify the prognostic value of ANS involvement and the role of autonomic parameters in predicting SARS-CoV-2 infection. According to the PRISMA guidelines, we performed a systematic review across Scopus and PubMed databases, resulting in 1585 records. The records check and the analysis of included reports’ references allowed us to include 22 articles. The studies were widely heterogeneous for study population, dysautonomia assessment, and COVID-19 severity. Heart rate variability was the tool most frequently chosen to analyze autonomic parameters, followed by automated pupillometry. Most studies found ANS involvement during acute COVID-19, and AD was often related to a worse outcome. Further studies are needed to clarify the role of autonomic parameters in predicting SARS-CoV-2 infection. The evidence emerging from this review suggests that a complex autonomic nervous system imbalance is a prominent feature of acute COVID-19, often leading to a poor prognosis.

Laboratory Biomarkers for Diagnosis and Prognosis in COVID-19

Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) causes a wide spectrum of clinical manifestations, with progression to multiorgan failure in the most severe cases. Several biomarkers can be altered in coronavirus disease 2019 (COVID-19), and they can be associated with diagnosis, prognosis, and outcomes. The most used biomarkers in COVID-19 include several proinflammatory cytokines, neuron-specific enolase (NSE), lactate dehydrogenase (LDH), aspartate transaminase (AST), neutrophil count, neutrophils-to-lymphocytes ratio, troponins, creatine kinase (MB), myoglobin, D-dimer, brain natriuretic peptide (BNP), and its N-terminal pro-hormone (NT-proBNP). Some of these biomarkers can be readily used to predict disease severity, hospitalization, intensive care unit (ICU) admission, and mortality, while others, such as metabolomic and proteomic analysis, have not yet translated to clinical practice. This narrative review aims to identify laboratory biomarkers that have shown significant diagnostic and prognostic value for risk stratification in COVID-19 and discuss the possible clinical application of novel analytic strategies, like metabolomics and proteomics. Future research should focus on identifying a limited but essential number of laboratory biomarkers to easily predict prognosis and outcome in severe COVID-19.

Non-Invasive Multimodal Neuromonitoring in Non-Critically Ill Hospitalized Adult Patients With COVID-19: A Systematic Review and Meta-Analysis

Introduction

Neurological complications are frequent in patients with coronavirus disease-2019 (COVID-19). The use of non-invasive neuromonitoring in subjects without primary brain injury but with potential neurological derangement is gaining attention outside the intensive care unit (ICU). This systematic review and meta-analysis investigates the use of non-invasive multimodal neuromonitoring of the brain in non-critically ill patients with COVID-19 outside the ICU and quantifies the prevalence of abnormal neuromonitoring findings in this population.

Methods

A structured literature search was performed in MEDLINE/PubMed, Scopus, Cochrane, and EMBASE to investigate the use of non-invasive neuromonitoring tools, including transcranial doppler (TCD); optic nerve sheath diameter (ONSD); near-infrared spectroscopy (NIRS); pupillometry; and electroencephalography (EEG) inpatients with COVID-19 outside the ICU. The proportion of non-ICU patients with CVOID-19 and a particular neurological feature at neuromonitoring at the study time was defined as prevalence.

Results

A total of 6,593 records were identified through literature searching. Twenty-one studies were finally selected, comprising 368 non-ICU patients, of whom 97 were considered for the prevalence of meta-analysis. The pooled prevalence of electroencephalographic seizures, periodic and rhythmic patterns, slow background abnormalities, and abnormal background on EEG was.17 (95% CI 0.04–0.29), 0.42 (95% CI 0.01–0.82), 0.92 (95% CI 0.83–1.01), and.95 (95% CI 0.088–1.09), respectively. No studies investigating NIRS and ONSD outside the ICU were found. The pooled prevalence for abnormal neuromonitoring findings detected using the TCD and pupillometry were incomputable due to insufficient data.

Conclusions

Neuromonitoring tools are non-invasive, less expensive, safe, and bedside available tools with a great potential for both diagnosis and monitoring of patients with COVID-19 at risk of brain derangements. However, extensive literature searching reveals that they are rarely used outside critical care settings.

Systematic Review Registration:www.crd.york.ac.uk/prospero/display_record.php?RecordID=265617, identifier: CRD42021265617.

Treating the body to prevent brain injury: lessons learned from the coronavirus disease 2019 pandemic

PURPOSE OF REVIEW

We aim to provide the current evidence on utility and application of neuromonitoring tools including electroencephalography (EEG), transcranial Doppler (TCD), pupillometry, optic nerve sheath diameter (ONSD), cerebral near-infrared spectroscopy (cNIRS), somatosensory-evoked potentials (SSEPs), and invasive intracranial monitoring in COVID-19. We also provide recent evidence on management strategy of COVID-19-associated neurological complications.

RECENT FINDINGS

Despite the common occurrence of neurological complications, we found limited use of standard neurologic monitoring in patients with COVID-19. No specific EEG pattern was identified in COVID-19. Frontal epileptic discharge was proposed to be a potential marker of COVID-19 encephalopathy. TCD, ONSD, and pupillometry can provide real-time data on intracranial pressure. Additionally, TCD may be useful for detection of acute large vessel occlusions, abnormal cerebral hemodynamics, cerebral emboli, and evolving cerebral edema at bedside. cNIRS was under-utilized in COVID-19 population and there are ongoing studies to investigate whether cerebral oxygenation could be a more useful parameter than peripheral oxygen saturation to guide clinical titration of permissive hypoxemia. Limited data exists on SSEPs and invasive intracranial monitoring.

SUMMARY

Early recognition using standardized neuromonitoring and timely intervention is important to reduce morbidity and mortality. The management strategy for neurological complications is similar to those without COVID-19.

The Importance of Neuromonitoring in Non Brain Injured Patients

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2022. Other selected articles can be found online at https://www.biomedcentral.com/collections/annualupdate2022. Further information about the Annual Update in Intensive Care and Emergency Medicine is available from https://link.springer.com/bookseries/8901.

The Use of Different Components of Brain Oxygenation for the Assessment of Cerebral Haemodynamics: A Prospective Observational Study on COVID-19 Patients

Introduction: The role of near-infrared spectroscopy (NIRS) for the evaluation of cerebral haemodynamics is gaining increasing popularity because of its noninvasive nature. The aim of this study was to evaluate the role of the integral components of regional cerebral oxygenation (rSO₂) measured by NIRS [i.e., arterial-oxyhemoglobin (O₂Hbi) and venous-deoxyhemoglobin (HHbi)-components], as indirect surrogates of cerebral blood flow (CBF) in a cohort of critically ill patients with coronavirus disease 2019 (COVID-19). We compared these findings to the gold standard technique for noninvasive CBF assessment, Transcranial Doppler (TCD). Methods: Mechanically ventilated patients with COVID-19 admitted to the Intensive Care Unit (ICU) of Policlinico San Martino Hospital, Genova, Italy, who underwent multimodal neuromonitoring (including NIRS and TCD), were included. rSO₂ and its components [relative changes in O₂Hbi, HHbi, and total haemoglobin (cHbi)] were compared with TCD (cerebral blood flow velocity, CBFV). Changes (Δ) in CBFV and rSO₂, ΔO₂Hbi, ΔHHbi, and ΔcHbi after systemic arterial blood pressure (MAP) modifications induced by different manoeuvres (e.g., rescue therapies and haemodynamic manipulation) were assessed using mixed-effect linear regression analysis and repeated measures correlation coefficients. All values were normalised as percentage changes from the baseline (Δ%). Results: One hundred and four measurements from 25 patients were included. Significant effects of Δ%MAP on Δ%CBF were observed after rescue manoeuvres for CBFV, ΔcHbi, and ΔO₂Hbi. The highest correlation was found between ΔCBFV and ΔΔO₂Hbi (R = 0.88, p < 0.0001), and the poorest between ΔCBFV and ΔΔHHbi (R = 0.34, p = 0.002). Conclusions: ΔO₂Hbi had the highest accuracy to assess CBF changes, reflecting its role as the main component for vasomotor response after changes in MAP. The use of indexes derived from the different components of rSO₂ can be useful for the bedside evaluation of cerebral haemodynamics in mechanically ventilated patients with COVID-19.

Instrumental Evaluation of COVID-19 Related Dysautonomia in Non-Critically-Ill Patients: An Observational, Cross-Sectional Study

Coronavirus disease-19 (COVID-19) is a predominantly respiratory syndrome. Growing reports about a SARS-CoV-2 neurological involvement, including autonomic dysfunction (AD), have been reported, mostly in critically-ill patients, or in the long-COVID syndrome. In this observational, cross-sectional study, we investigated the prevalence of AD in 20 non-critically-ill COVID-19 patients (COVID+ group) in the acute phase of the disease through a composite instrumental evaluation consisting of Sudoscan, automated pupillometry, heart rate variability (HRV), and pulse transit time (PTT). All the parameters were compared to a control group of 20 healthy volunteers (COVID− group). COVID+ group presented higher values of pupillary dilatation velocities, and baseline pupil diameter than COVID− subjects. Moreover, COVID+ patients presented a higher incidence of feet sudomotor dysfunction than COVID− group. No significant differences emerged in HRV and PTT parameters between groups. In this study we observed the occurrence of autonomic dysfunction in the early stage of the disease.

Severe stroke in patients admitted to intensive care unit after COVID-19 infection: pictorial essay of a case series

Patients infected by COVID-19 could require intensive care unit admission especially due to acute respiratory failure. However, neurological manifestations are very common. Among these, ischemic stroke or cerebral hemorrhage may have unfavorable outcome. The mechanisms leading to cerebral damage by SARS-CoV2 are still under debate. One of the most accepted theories implies an endothelial activation which in turns increase the risk of thrombus formation with the development of stroke, either ischemic or hemorrhagic. The more severe the COVID-19 disease, the higher the risk of stroke. Stroke in ICU patients are not frequent, but cerebral hemorrhage has devastating effects with high mortality. In these pictorial essay of case reports, main clinical aspects are discussed, along with a summary of the evidence about pathophysiology and treatment of these patients.

Mental and neurological disorders and risk of COVID-19 susceptibility, illness severity and mortality: A systematic review, meta-analysis and call for action

BACKGROUND

Coronavirus disease 2019 (COVID-19) has evolved into a worldwide pandemic, and has been found to be closely associated with mental and neurological disorders. We aimed to comprehensively quantify the association between mental and neurological disorders, both pre-existing and subsequent, and the risk of susceptibility, severity and mortality of COVID-19.

METHODS

In this systematic review and meta-analysis, we searched PubMed, Web of Science, Embase, PsycINFO, and Cochrane library databases for studies published from the inception up to January 16, 2021 and updated at July 7, 2021. Observational studies including cohort and case-control, cross-sectional studies and case series that reported risk estimates of the association between mental or neurological disorders and COVID-19 susceptibility, illness severity and mortality were included. Two researchers independently extracted data and conducted the quality assessment. Based on I2 heterogeneity, we used a random effects model to calculate pooled odds ratios (OR) and 95% confidence intervals (95% CI). Subgroup analyses and meta-regression analysis were also performed. This study was registered on PROSPERO (registration number: CRD 42021230832).

FINDING

A total of 149 studies (227,351,954 participants, 89,235,737 COVID-19 patients) were included in this analysis, in which 27 reported morbidity (132,727,798), 56 reported illness severity (83,097,968) and 115 reported mortality (88,878,662). Overall, mental and neurological disorders were associated with a significant high risk of infection (pre-existing mental: OR 1·67, 95% CI 1·12-2·49; and pre-existing neurological: 2·05, 1·58-2·67), illness severity (mental: pre-existing, 1·40, 1·25-1·57; sequelae, 4·85, 2·53-9·32; neurological: pre-existing, 1·43, 1·09-1·88; sequelae, 2·17, 1·45-3·24), and mortality (mental: pre-existing, 1·47, 1·26-1·72; neurological: pre-existing, 2·08, 1·61-2·69; sequelae, 2·03, 1·66-2·49) from COVID-19. Subgroup analysis revealed that association with illness severity was stronger among younger COVID-19 patients, and those with subsequent mental disorders, living in low- and middle-income regions. Younger patients with mental and neurological disorders were associated with higher mortality than elders. For type-specific mental disorders, susceptibility to contracting COVID-19 was associated with pre-existing mood disorders, anxiety, and attention-deficit hyperactivity disorder (ADHD); illness severity was associated with both pre-existing and subsequent mood disorders as well as sleep disturbance; and mortality was associated with pre-existing schizophrenia. For neurological disorders, susceptibility was associated with pre-existing dementia; both severity and mortality were associated with subsequent delirium and altered mental status; besides, mortality was associated with pre-existing and subsequent dementia and multiple specific neurological diseases. Heterogeneities were substantial across studies in most analysis.

INTERPRETATION

The findings show an important role of mental and neurological disorders in the context of COVID-19 and provide clues and directions for identifying and protecting vulnerable populations in the pandemic. Early detection and intervention for neurological and mental disorders are urgently needed to control morbidity and mortality induced by the COVID-19 pandemic. However, there was substantial heterogeneity among the included studies, and the results should be interpreted with caution. More studies are needed to explore long-term mental and neurological sequela, as well as the underlying brain mechanisms for the sake of elucidating the causal pathways for these associations.

FUNDING

This study is supported by grants from the National Key Research and Development Program of China, the National Natural Science Foundation of China, Special Research Fund of PKUHSC for Prevention and Control of COVID-19, and the Fundamental Research Funds for the Central Universities.

Is Increased Intracranial Pressure a Factor in Persistent Headache After Coronavirus Disease 2019?

ABSTRACT

This study aimed to determine pain characteristics in patients with persistent headache after COVID-19 and to investigate the role of increased intracranial pressure (ICP) in the pathogenesis of this headache. This is a case-control study comparing the parameters and measurements indicating increased ICP based on magnetic resonance imaging between COVID-19-diagnosed patients with persistent headache and a control group. Optic nerve sheath diameter (ONSD) and eyeball transverse diameter (ETD) were performed on the left eye of each participant. Seventeen of the patients (53.12%) met the diagnostic criteria for new daily persistent headache. Seven patients (21.87%) had migraine, and eight (25%) had tension headache characteristics. No significant difference was observed between the patient and control groups in terms of the ONSD and ETD values. It is possible that the etiopathogenesis is multifactorial. We consider that future studies that will evaluate ICP measurements in large patient groups can present a different perspective for this subject.

What can the neurological manifestations of COVID-19 tell us: a meta-analysis

Background

Covid-19 became a global pandemic in 2019. Studies have shown that coronavirus can cause neurological symptoms, but clinical studies on its neurological symptoms are limited. In this meta-analysis, we aimed to summarize the various neurological manifestations that occurred in COVID-19 patients and calculate the incidence of various neurological manifestations. At the same time, we further explored the mechanism of nervous system injury and prognosis in COVID-19 patients in combination with their nervous system manifestations. This study provides a reference for early clinical identification of COVID-19 nervous system injury in the future, so as to achieve early treatment and reduce neurological sequelae.

Methods

We systematically searched all published English literature related to the neurological manifestations of COVID-19 from January 1, 2020, to April 30, 2021, in Pubmed, Embase, and Cochrane Library. The keywords used were COVID-19 and terminology related to the nervous system performance. All included studies were selected by two independent reviewers using EndNote and NoteExpress software, any disagreement was resolved by consensus or by a third reviewer, and the selected data were then collected for meta-analysis using a random-effects model.

Results

A total of 168 articles (n = 292,693) were included in the study, and the meta-analysis showed that the most common neurological manifestations of COVID-19 were myalgia(33%; 95%CI 0.30–0.37; I² = 99.17%), smell impairment(33%; 95%CI 0.28–0.38; I² = 99.40%), taste dysfunction(33%; 95%CI 0.27–0.39; I² = 99.09%), altered mental status(32%; 95%CI 0.22–0.43; I² = 99.06%), headache(29%; 95%CI 0.25–0.33; I² = 99.42%), encephalopathy(26%; 95%CI 0.16–0.38; I² = 99.31%), alteration of consciousness(13%; 95%CI 0.08–0.19; I² = 98.10%), stroke(12%; 95%CI 0.08–0.16; I² = 98.95%), dizziness(10%; 95%CI 0.08–0.13; I² = 96.45%), vision impairment(6%; 95%CI 0.03–0.09; I² = 86.82%), intracerebral haemorrhage(5%; 95%CI 0.03–0.09; I² = 95.60%), seizure(4%; 95%CI 0.02 -0.05; I² = 98.15%), encephalitis(2%; 95%CI 0.01–0.03; I² = 90.36%), Guillan-Barré Syndrome (GBS) (1%; 95%CI 0.00–0.03; I² = 89.48%).

Conclusions

Neurological symptoms are common and varied in Covid-19 infections, and a growing number of reports suggest that the prevalence of neurological symptoms may be increasing. In the future, the role of COVID-19 neurological symptoms in the progression of COVID-19 should be further studied, and its pathogenesis and assessment methods should be explored, to detect and treat early neurological complications of COVID-19 and reduce mortality.

Autonomic dysfunction in post-COVID patients with and witfhout neurological symptoms: a prospective multidomain observational study

The autonomic nervous system (ANS) can be affected by COVID-19, and dysautonomia may be a possible complication in post-COVID individuals. Orthostatic hypotension (OH) and postural tachycardia syndrome (POTS) have been suggested to be common after SARS-CoV-2 infection, but other components of ANS function may be also impaired. The Composite Autonomic Symptom Scale 31 (COMPASS-31) questionnaire is a simple and validated tool to assess dysautonomic symptoms. The aim of the present study was to administer the COMPASS-31 questionnaire to a sample of post-COVID patients with and without neurological complaints. Participants were recruited among the post-COVID ambulatory services for follow-up evaluation between 4 weeks and 9 months from COVID-19 symptoms onset. Participants were asked to complete the COMPASS-31 questionnaire referring to the period after COVID-19 disease. Heart rate and blood pressure were manually taken during an active stand test for OH and POTS diagnosis. One-hundred and eighty participants were included in the analysis (70.6% females, 51 ± 13 years), and OH was found in 13.8% of the subjects. Median COMPASS-31 score was 17.6 (6.9-31.4), with the most affected domains being orthostatic intolerance, sudomotor, gastrointestinal and pupillomotor dysfunction. A higher COMPASS-31 score was found in those with neurological symptoms (p < 0.01), due to more severe orthostatic intolerance symptoms (p < 0.01), although gastrointestinal (p < 0.01), urinary (p < 0.01), and pupillomotor (p < 0.01) domains were more represented in the non-neurological symptoms group. This study confirms the importance of monitoring ANS symptoms as a possible complication of COVID-19 disease that may persist in the post-acute period.

Cerebral Hemodynamics and Intracranial Compliance Impairment in Critically Ill COVID-19 Patients: A Pilot Study

Introduction: One of the possible mechanisms by which the new coronavirus (SARS-Cov2) could induce brain damage is the impairment of cerebrovascular hemodynamics (CVH) and intracranial compliance (ICC) due to the elevation of intracranial pressure (ICP). The main objective of this study was to assess the presence of CVH and ICC alterations in patients with COVID-19 and evaluate their association with short-term clinical outcomes. Methods: Fifty consecutive critically ill COVID-19 patients were studied with transcranial Doppler (TCD) and non-invasive monitoring of ICC. Subjects were included upon ICU admission; CVH was evaluated using mean flow velocities in the middle cerebral arteries (mCBFV), pulsatility index (PI), and estimated cerebral perfusion pressure (eCPP), while ICC was assessed by using the P2/P1 ratio of the non-invasive ICP curve. A CVH/ICC score was computed using all these variables. The primary composite outcome was unsuccessful in weaning from respiratory support or death on day 7 (defined as UO). Results: At the first assessment (n = 50), only the P2/P1 ratio (median 1.20 [IQRs 1.00–1.28] vs. 1.00 [0.88–1.16]; p = 0.03) and eICP (14 [11–25] vs. 11 [7–15] mmHg; p = 0.01) were significantly higher among patients with an unfavorable outcome (UO) than others. Patients with UO had a significantly higher CVH/ICC score (9 [8–12] vs. 6 [5–7]; p < 0.001) than those with a favorable outcome; the area under the receiver operating curve (AUROC) for CVH/ICC score to predict UO was 0.86 (95% CIs 0.75–0.97); a score > 8.5 had 63 (46–77)% sensitivity and 87 (62–97)% specificity to predict UO. For those patients undergoing a second assessment (n = 29), after a median of 11 (5–31) days, all measured variables were similar between the two time-points. No differences in the measured variables between ICU non-survivors (n = 30) and survivors were observed. Conclusions: ICC impairment and CVH disturbances are often present in COVID-19 severe illness and could accurately predict an early poor outcome.

Early Effects of Passive Leg-Raising Test, Fluid Challenge, and Norepinephrine on Cerebral Autoregulation and Oxygenation in COVID-19 Critically Ill Patients

Background: Coronavirus disease 2019 (COVID-19) patients are at high risk of neurological complications consequent to several factors including persistent hypotension. There is a paucity of data on the effects of therapeutic interventions designed to optimize systemic hemodynamics on cerebral autoregulation (CA) in this group of patients. Methods: Single-center, observational prospective study conducted at San Martino Policlinico Hospital, Genoa, Italy, from October 1 to December 15, 2020. Mechanically ventilated COVID-19 patients, who had at least one episode of hypotension and received a passive leg raising (PLR) test, were included. They were then treated with fluid challenge (FC) and/or norepinephrine (NE), according to patients' clinical conditions, at different moments. The primary outcome was to assess the early effects of PLR test and of FC and NE [when clinically indicated to maintain adequate mean arterial pressure (MAP)] on CA (CA index) measured by transcranial Doppler (TCD). Secondary outcomes were to evaluate the effects of PLR test, FC, and NE on systemic hemodynamic variables, cerebral oxygenation (rSo₂), and non-invasive intracranial pressure (nICP). Results: Twenty-three patients were included and underwent PLR test. Of these, 22 patients received FC and 14 were treated with NE. The median age was 62 years (interquartile range = 57-68.5 years), and 78% were male. PLR test led to a low CA index [58% (44-76.3%)]. FC and NE administration resulted in a CA index of 90.8% (74.2-100%) and 100% (100-100%), respectively. After PLR test, nICP based on pulsatility index and nICP based on flow velocity diastolic formula was increased [18.6 (17.7-19.6) vs. 19.3 (18.2-19.8) mm Hg, p = 0.009, and 12.9 (8.5-18) vs. 15 (10.5-19.7) mm Hg, p = 0.001, respectively]. PLR test, FC, and NE resulted in a significant increase in MAP and rSo₂. Conclusions: In mechanically ventilated severe COVID-19 patients, PLR test adversely affects CA. An individualized strategy aimed at assessing both the hemodynamic and cerebral needs is warranted in patients at high risk of neurological complications.

Early effects of ventilatory rescue therapies on systemic and cerebral oxygenation in mechanically ventilated COVID-19 patients with acute respiratory distress syndrome: a prospective observational study

BACKGROUND

In COVID-19 patients with acute respiratory distress syndrome (ARDS), the effectiveness of ventilatory rescue strategies remains uncertain, with controversial efficacy on systemic oxygenation and no data available regarding cerebral oxygenation and hemodynamics.

METHODS

This is a prospective observational study conducted at San Martino Policlinico Hospital, Genoa, Italy. We included adult COVID-19 patients who underwent at least one of the following rescue therapies: recruitment maneuvers (RMs), prone positioning (PP), inhaled nitric oxide (iNO), and extracorporeal carbon dioxide (CO2) removal (ECCO2R). Arterial blood gas values (oxygen saturation [SpO2], partial pressure of oxygen [PaO2] and of carbon dioxide [PaCO2]) and cerebral oxygenation (rSO2) were analyzed before (T0) and after (T1) the use of any of the aforementioned rescue therapies. The primary aim was to assess the early effects of different ventilatory rescue therapies on systemic and cerebral oxygenation. The secondary aim was to evaluate the correlation between systemic and cerebral oxygenation in COVID-19 patients.

RESULTS

Forty-five rescue therapies were performed in 22 patients. The median [interquartile range] age of the population was 62 [57-69] years, and 18/22 [82%] were male. After RMs, no significant changes were observed in systemic PaO2 and PaCO2 values, but cerebral oxygenation decreased significantly (52 [51-54]% vs. 49 [47-50]%, p < 0.001). After PP, a significant increase was observed in PaO2 (from 62 [56-71] to 82 [76-87] mmHg, p = 0.005) and rSO2 (from 53 [52-54]% to 60 [59-64]%, p = 0.005). The use of iNO increased PaO2 (from 65 [67-73] to 72 [67-73] mmHg, p = 0.015) and rSO2 (from 53 [51-56]% to 57 [55-59]%, p = 0.007). The use of ECCO2R decreased PaO2 (from 75 [75-79] to 64 [60-70] mmHg, p = 0.009), with reduction of rSO2 values (59 [56-65]% vs. 56 [53-62]%, p = 0.002). In the whole population, a significant relationship was found between SpO2 and rSO2 (R = 0.62, p < 0.001) and between PaO2 and rSO2 (R0 0.54, p < 0.001).

CONCLUSIONS

Rescue therapies exert specific pathophysiological mechanisms, resulting in different effects on systemic and cerebral oxygenation in critically ill COVID-19 patients with ARDS. Cerebral and systemic oxygenation are correlated. The choice of rescue strategy to be adopted should take into account both lung and brain needs. Registration The study protocol was approved by the ethics review board (Comitato Etico Regione Liguria, protocol n. CER Liguria: 23/2020).

Rehabilitation and COVID-19: a rapid living systematic review by Cochrane Rehabilitation Field updated as of December 31st, 2020 and synthesis of the scientific literature of 2020

INTRODUCTION

COVID-19 infection significantly increased mortality risk and the burden of disability in most survivors, regardless of symptom severity at onset. The rehabilitation needs of people infected are receiving growing attention, as evidenced by the increasing number of publications, including those addressing the chronic consequences of infection. This rapid living systematic review reports the evidence published in November and December 2020 and summarises the entire body of literature on rehabilitation in COVID-19 patients published in 2020.

EVIDENCE ACQUISITION

This update was performed using the methodology reported by the second edition conducted by Cochrane Rehabilitation REH-COVER Action. We searched PubMed, Embase, CINAHL, Scopus, Web of Science, and Pedro databases. Papers related to COVID-19 and rehabilitation were retrieved and summarised descriptively.

EVIDENCE SYNTHESIS

The search retrieved 4441 studies. After the removal of duplicates and the screening for title and abstract, we retained 105 studies. Of these, we included 54 in the qualitative synthesis of this update. According to OCEBM 2011 levels of evidence table, most studies (64.8%) fall within the category of level 4 evidence. Up to 40.7% of papers included COVID-19 patients in the postacute phase. In 2020, our rapid living systematic review included 230 studies; most of these (73.9%) were level 4 studies, 25.7% were level 3, and only one study was level 2. The evidence level improved over time. While most studies (44.8%) included patients with acute COVID-19, we observed a gradual increase in the number of reports about chronic symptoms and the long-term consequences of the infection.

CONCLUSIONS

The update of the rapid living systematic review by Cochrane Rehabilitation Field demonstrates an increase in the level of evidence of studies addressing the rehabilitation needs associated with COVID-19 infection. Although most studies are still case reports/series, there is a trend towards conducting prospective investigations of the early natural history of the disease (first months post onset). High-quality-level studies on the efficacy of rehabilitation, and long-term monitoring of the disease and its sequelae are yet to emerge.