Multimodal Prediction of 3- and 12-Month Outcomes in ICU Patients with Acute Disorders of Consciousness

BACKGROUND

In intensive care unit (ICU) patients with coma and other disorders of consciousness (DoC), outcome prediction is key to decision-making regarding prognostication, neurorehabilitation, and management of family expectations. Current prediction algorithms are largely based on chronic DoC, whereas multimodal data from acute DoC are scarce. Therefore, the Consciousness in Neurocritical Care Cohort Study Using Electroencephalography and Functional Magnetic Resonance Imaging (i.e. CONNECT-ME; ClinicalTrials.gov identifier: NCT02644265) investigates ICU patients with acute DoC due to traumatic and nontraumatic brain injuries, using electroencephalography (EEG) (resting-state and passive paradigms), functional magnetic resonance imaging (fMRI) (resting-state) and systematic clinical examinations.

METHODS

We previously presented results for a subset of patients (n = 87) concerning prediction of consciousness levels in the ICU. Now we report 3- and 12-month outcomes in an extended cohort (n = 123). Favorable outcome was defined as a modified Rankin Scale score ≤ 3, a cerebral performance category score ≤ 2, and a Glasgow Outcome Scale Extended score ≥ 4. EEG features included visual grading, automated spectral categorization, and support vector machine consciousness classifier. fMRI features included functional connectivity measures from six resting-state networks. Random forest and support vector machine were applied to EEG and fMRI features to predict outcomes. Here, random forest results are presented as areas under the curve (AUC) of receiver operating characteristic curves or accuracy. Cox proportional regression with in-hospital death as a competing risk was used to assess independent clinical predictors of time to favorable outcome.

RESULTS

Between April 2016 and July 2021, we enrolled 123 patients (mean age 51 years, 42% women). Of 82 (66%) ICU survivors, 3- and 12-month outcomes were available for 79 (96%) and 77 (94%), respectively. EEG features predicted both 3-month (AUC 0.79 [95% confidence interval (CI) 0.77-0.82]) and 12-month (AUC 0.74 [95% CI 0.71-0.77]) outcomes. fMRI features appeared to predict 3-month outcome (accuracy 0.69-0.78) both alone and when combined with some EEG features (accuracies 0.73-0.84) but not 12-month outcome (larger sample sizes needed). Independent clinical predictors of time to favorable outcome were younger age (hazard ratio [HR] 1.04 [95% CI 1.02-1.06]), traumatic brain injury (HR 1.94 [95% CI 1.04-3.61]), command-following abilities at admission (HR 2.70 [95% CI 1.40-5.23]), initial brain imaging without severe pathological findings (HR 2.42 [95% CI 1.12-5.22]), improving consciousness in the ICU (HR 5.76 [95% CI 2.41-15.51]), and favorable visual-graded EEG (HR 2.47 [95% CI 1.46-4.19]).

CONCLUSIONS

Our results indicate that EEG and fMRI features and readily available clinical data predict short-term outcome of patients with acute DoC and that EEG also predicts 12-month outcome after ICU discharge.

Vertebro-Vertebral Fistula Occlusion Using a Woven EndoBridgeTM-Device

Vertebro-vertebral fistulas (VVFs) are vascular lesions that may develop after trauma or spontaneously in association with connective tissue disorders. We present a rare case of a post-traumatic VVF in a young patient presenting with a painless swelling and a bruit in her left upper neck. Digital subtraction angiography showed an arteriovenous fistula between the left vertebral artery (VA) and the vertebral venous plexus with significant steal phenomenon. Endovascular therapy was performed using a Woven EndoBridgeTM (WEB)-device combined with coils that allowed preservation of the VA. The patient fully recovered from her symptoms and follow-up imaging showed stable occlusion. In conclusion, VVFs can be effectively treated using intrasaccular flow diverters such as the WEB-device, allowing for complete and stable occlusion while preserving the parent artery.

Multimodal prediction of residual consciousness in the intensive care unit: the CONNECT-ME study

Functional MRI (fMRI) and EEG may reveal residual consciousness in patients with disorders of consciousness (DoC), as reflected by a rapidly expanding literature on chronic DoC. However, acute DoC is rarely investigated, although identifying residual consciousness is key to clinical decision-making in the intensive care unit (ICU). Therefore, the objective of the prospective, observational, tertiary centre cohort, diagnostic phase IIb study 'Consciousness in neurocritical care cohort study using EEG and fMRI' (CONNECT-ME, NCT02644265) was to assess the accuracy of fMRI and EEG to identify residual consciousness in acute DoC in the ICU. Between April 2016 and November 2020, 87 acute DoC patients with traumatic or non-traumatic brain injury were examined with repeated clinical assessments, fMRI and EEG. Resting-state EEG and EEG with external stimulations were evaluated by visual analysis, spectral band analysis and a Support Vector Machine (SVM) consciousness classifier. In addition, within- and between-network resting-state connectivity for canonical resting-state fMRI networks was assessed. Next, we used EEG and fMRI data at study enrolment in two different machine-learning algorithms (Random Forest and SVM with a linear kernel) to distinguish patients in a minimally conscious state or better (≥MCS) from those in coma or unresponsive wakefulness state (≤UWS) at time of study enrolment and at ICU discharge (or before death). Prediction performances were assessed with area under the curve (AUC). Of 87 DoC patients (mean age, 50.0 ± 18 years, 43% female), 51 (59%) were ≤UWS and 36 (41%) were ≥ MCS at study enrolment. Thirty-one (36%) patients died in the ICU, including 28 who had life-sustaining therapy withdrawn. EEG and fMRI predicted consciousness levels at study enrolment and ICU discharge, with maximum AUCs of 0.79 (95% CI 0.77-0.80) and 0.71 (95% CI 0.77-0.80), respectively. Models based on combined EEG and fMRI features predicted consciousness levels at study enrolment and ICU discharge with maximum AUCs of 0.78 (95% CI 0.71-0.86) and 0.83 (95% CI 0.75-0.89), respectively, with improved positive predictive value and sensitivity. Overall, both machine-learning algorithms (SVM and Random Forest) performed equally well. In conclusion, we suggest that acute DoC prediction models in the ICU be based on a combination of fMRI and EEG features, regardless of the machine-learning algorithm used.

Temperature change in children undergoing magnetic resonance imaging-An observational cohort study

AIM

An increasing number of children undergo magnetic resonance imaging requiring anesthesia or sedation to ensure their immobility; however, magnetic resonance imaging may increase body temperature whereas sedation or anesthesia may decrease it. We investigated changes in body temperature in children who underwent sedation or anesthesia for magnetic resonance imaging.

METHODS

Children aged 12 weeks-12 years undergoing anesthesia and magnetic resonance imaging were included in this prospective observational study. Tympanic body temperature was measured before and after magnetic resonance imaging, and the difference between measurements was calculated. Associations between the temperature difference and patient- or procedure-related factors were evaluated with linear and logistic regression analysis.

RESULTS

A total of 74 children were included, of whom 5 (7%) had a temperature increase ≥0.5°C. Mean temperature difference was -0.24°C (SD 0.48) for the entire group and -0.28°C for the youngest children (0-2 years). The temperature difference correlated positively with the duration of imaging (unadjusted coefficient 0.26, 95% confidence interval (CI), (0.01; 0.52)).

CONCLUSION

In this study of sedated or anesthetized children undergoing magnetic resonance imaging, clinically relevant increases in body temperature above 0.5°C were only found in a few patients. However, longer imaging duration tended to be associated with increased body temperature.

Case Report: Giant Paraganglioma of the Skull Base With Two Somatic Mutations in SDHB and PTEN Genes

Head and neck paragangliomas (HNPGLs) are neuroendocrine tumors. They arise from the parasympathetic ganglia and can be either sporadic or due to hereditary syndromes (up to 40%). Most HNPGLs do not produce significant amounts of catecholamines. We report a case of a giant paraganglioma of the skull base with an unusually severe presentation secondary to excessive release of norepinephrine, with a good outcome considering the severity of disease. A 39-year-old Caucasian woman with no prior medical history was found unconscious and emaciated in her home. In the intensive care unit (ICU) the patient was treated for multi-organ failure with multiple complications and difficulties in stabilizing her blood pressure with values up to 246/146 mmHg. She was hospitalized in the ICU for 72 days and on the 31^st day clinical assessment revealed jugular foramen syndrome and paralysis of the right n. facialis. A brain MRI confirmed a right-sided tumor of the skull base of 93.553 cm³. Blood tests showed high amounts of normetanephrine (35.1-45.4 nmol/L, ref <1.09 nmol/L) and a tumor biopsy confirmed the diagnosis of a paraganglioma. Phenoxybenzamine and Labetalol were used in high doses ((Dibenyline^®, 90 mg x 3 daily) and labetalol (Trandate^®, 200 + 300 + 300 mg daily) to stabilize blood pressure. The patient underwent two tumor embolization procedures before total tumor resection on day 243. Normetanephrine and blood pressure normalized after surgery (0.77 nmol/L, ref: < 1.09 nmol/L). The damage to the cranial nerve was permanent. Our patient was comprehensively examined for germline predisposition to PPGLs, however we did not identify any causal aberrations. A somatic deletion and loss of heterozygosity (LOH) of the short arm (p) of chromosome 1 (including SDHB) and p of chromosome 11 was found. Analysis showed an SDHB (c.565T>G, p.C189G) and PTEN (c.834C>G, p.F278L) missense mutation in tumor DNA. The patient made a remarkable recovery except for neurological deficits after intensive multidisciplinary treatment and rehabilitation. This case demonstrates the necessity for an early tertiary center approach with a multidisciplinary expert team and highlights the efficacy of the correct treatment with alpha-blockade.

Altered brown fat thermoregulation and enhanced cold-induced thermogenesis in young, healthy, winter-swimming men

The Scandinavian winter-swimming culture combines brief dips in cold water with hot sauna sessions, with conceivable effects on body temperature. We study thermogenic brown adipose tissue (BAT) in experienced winter-swimming men performing this activity 2–3 times per week. Our data suggest a lower thermal comfort state in the winter swimmers compared with controls, with a lower core temperature and absence of BAT activity. In response to cold, we observe greater increases in cold-induced thermogenesis and supraclavicular skin temperature in the winter swimmers, whereas BAT glucose uptake and muscle activity increase similarly to those of the controls. All subjects demonstrate nocturnal reduction in supraclavicular skin temperature, whereas a distinct peak occurs at 4:30–5:30 a.m. in the winter swimmers. Our data leverage understanding of BAT in adult human thermoregulation, suggest both heat and cold acclimation in winter swimmers, and propose winter swimming as a potential strategy for increasing energy expenditure.

Winter swimmers have a lower core temperature at a thermal comfort state than controls

Winter swimmers had no BAT glucose uptake at a thermal comfort state

Winter swimmers have higher cold-induced thermogenesis than control subjects

Human supraclavicular skin temperature varies with a diurnal rhythm

Pantoprazole in Patients at Risk for Gastrointestinal Bleeding in the ICU

BACKGROUND

Prophylaxis for gastrointestinal stress ulceration is frequently given to patients in the intensive care unit (ICU), but its risks and benefits are unclear.

METHODS

In this European, multicenter, parallel-group, blinded trial, we randomly assigned adults who had been admitted to the ICU for an acute condition (i.e., an unplanned admission) and who were at risk for gastrointestinal bleeding to receive 40 mg of intravenous pantoprazole (a proton-pump inhibitor) or placebo daily during the ICU stay. The primary outcome was death by 90 days after randomization.

RESULTS

A total of 3298 patients were enrolled; 1645 were randomly assigned to the pantoprazole group and 1653 to the placebo group. Data on the primary outcome were available for 3282 patients (99.5%). At 90 days, 510 patients (31.1%) in the pantoprazole group and 499 (30.4%) in the placebo group had died (relative risk, 1.02; 95% confidence interval [CI], 0.91 to 1.13; P=0.76). During the ICU stay, at least one clinically important event (a composite of clinically important gastrointestinal bleeding, pneumonia, Clostridium difficile infection, or myocardial ischemia) had occurred in 21.9% of patients assigned to pantoprazole and 22.6% of those assigned to placebo (relative risk, 0.96; 95% CI, 0.83 to 1.11). In the pantoprazole group, 2.5% of patients had clinically important gastrointestinal bleeding, as compared with 4.2% in the placebo group. The number of patients with infections or serious adverse reactions and the percentage of days alive without life support within 90 days were similar in the two groups.

CONCLUSIONS

Among adult patients in the ICU who were at risk for gastrointestinal bleeding, mortality at 90 days and the number of clinically important events were similar in those assigned to pantoprazole and those assigned to placebo. (Funded by Innovation Fund Denmark and others; SUP-ICU ClinicalTrials.gov number, NCT02467621 .).

Failed needle decompression of bilateral spontaneous tension pneumothorax

This case report presents a young male admitted with primary bilateral spontaneous tension pneumothorax and severe respiratory distress. This is an extremely rare condition. The patient was on the verge of hypoxic cardiac arrest and the attempted needle thoracocentesis was unsuccessful. Needle thoracocentesis in the midclavicular line of the second intercostal space is widely used and recommended as first-line treatment of tension pneumothorax. Reviewing the literature, the procedure is not based on solid evidence. It has high failure rates and potentially serious complications. Alternatives to this approach are perhaps more appropriate. Correctly done, needle thoracocentesis has its place in the presence of a diagnosed or suspected tension pneumothorax when no other options are available. If needle thoracocentesis is chosen, then insertion in the mid-anterior axillary line of the 3rd-5th intercostal space is an appropriate alternative site. Otherwise, lateral thoracostomy, with or without chest tube insertion, is a safe procedure with a high success rate. It should be considered as the first-line treatment of tension pneumothorax, particularly in the unstable patient.

Assessing response to stroke thrombolysis: validation of 24-hour multimodal magnetic resonance imaging

BACKGROUND

Imaging is used as a surrogate for clinical outcome in early-phase stroke trials. Assessment of infarct growth earlier than the standard 90 days used for clinical end points may be equally accurate and more practical.

OBJECTIVE

To compare assessment of the effect of reperfusion therapies using 24-hour vs day 90 magnetic resonance imaging.

DESIGN

Infarct volume was assessed on diffusion-weighted imaging (DWI) at baseline and 24 hours after stroke onset and on fluid-attenuated inversion recovery images at day 90. The DWI and fluid-attenuated inversion recovery lesions were manually outlined by 2 independent raters, and the volumes were averaged. Interrater consistency was assessed using the median difference in lesion volume between raters.

SETTING

Referral center. Patients  Imaging data were available for 83 patients; 77 of these patients received thrombolysis.

MAIN OUTCOME MEASURES

Infarct volume at 24 hours and 90 days.

RESULTS

The 24-hour DWI infarct volume had a strong linear correlation with day 90 fluid-attenuated inversion recovery infarct volume (r = 0.98, 95% confidence interval, 0.97-0.99). Recanalization had a significant effect on infarct evolution between baseline and 24 hours but not between 24 hours and day 90. Infarct growth from baseline was significantly reduced by recanalization, whether assessed at 24 hours or day 90. Infarct volume at either time point predicted functional outcome independent of age and baseline stroke severity. Interrater agreement was better for DWI than fluid-attenuated inversion recovery (1.4 mL [8%] vs 1.8 mL [17%]; P = .002).

CONCLUSIONS

Assessment of final infarct volume using DWI at 24 hours captures the effect of reperfusion therapies on infarct growth and predicts functional outcome similarly to imaging at day 90. This has the potential to reduce loss to follow-up in trials and may add early prognostic information in clinical practice.

Erythropoietin does not attenuate renal dysfunction or inflammation in a porcine model of endotoxemia

BACKGROUND

Erythropoietin (EPO) is a multifunctional cytokine with anti-apoptotic, anti-inflammatory, and organ protective effects. EPO protects against ischemia-reperfusion injuries, and recent reports suggest that EPO also prevents organ dysfunction in experimental sepsis. The aims of this study were to determine whether EPO prevents endotoxemia-induced organ dysfunction in a porcine model and to characterize the immunomodulatory and anti-apoptotic effects of EPO.

METHODS

Twenty-eight pigs were randomly assigned to three groups: (1) endotoxemia treated with EPO 5000 IU/kg, (2) endotoxemia treated with placebo, and (3) a sham group anesthetized and submitted to sham operation without treatment. A laparotomy was performed, and a flow probe was placed around the left renal artery, which allowed renal blood flow (RBF) measurements. Endotoxemia was induced by an infusion of lipopolysaccharide. After 2 h, the infusion was reduced to a maintenance dose and the animals were fluid resuscitated. The glomerular filtration rate (GFR), RBF, renal oxygen consumption, and plasma cytokines [interleukin (IL)-1β, IL-6, IL-8, IL-10, and tumor necrosis factor-alpha] were analyzed. Renal biopsies were analyzed for cytokine content and apoptosis.

RESULTS

Endotoxemia elicited impaired renal function, estimated as GFR, and increased the levels of renal apoptotic cells, with no modifying effect of EPO. Furthermore, EPO had no effect on RBF, renal oxygen consumption, or the systemic hemodynamic response to endotoxemia. EPO did not modify the inflammatory response, measured as changes in cytokine levels in plasma and organs.

CONCLUSION

EPO did not confer renal protection in this fluid-resuscitated porcine model of endotoxemia, and EPO did not modify the inflammatory response.

Erythropoietin administration is associated with short-term improvement in glomerular filtration rate after ischemia-reperfusion injury

BACKGROUND

Erythropoietin (EPO) is a cytokine with organ-protective properties. We hypothesized that EPO could attenuate acute renal dysfunction and inflammation in a porcine model of ischemia-reperfusion (IR). Furthermore, we aimed to characterize the impact of EPO on systemic and renal hemodynamics, and renal oxygen consumption.

METHODS

Twenty-four pigs were randomly assigned to three groups: (1) EPO (5000 IU/kg) administered intravenously before IR (n=9), (2) placebo administered before IR (n=9), or (3) sham group, anesthetized and operated on only (n=6). IR was induced by clamping the left renal artery for 45 min. Hemodynamics and renal blood flow (RBF) were analyzed continuously. Glomerular filtration rate (GFR), renal oxygen consumption, and plasma cytokines (IL-1β, IL-6, IL-8, IL-10, and TNF-α) were analyzed hourly. Renal biopsies were analyzed for cytokine content and apoptosis.

RESULTS

GFR was higher during reperfusion in the EPO group than in the placebo group (P<0.01). No differences between the IR groups were found in hemodynamics, RBF, oxygen consumption, or renal apoptosis. The levels of TNF-α in the plasma (P=0.036) and the levels of TNF-α and IL-10 in the renal cortex (P=0.04 and P=0.01, respectively) were lower in the EPO group compared with the sham group.

CONCLUSION

EPO attenuated the renal dysfunction as estimated as GFR. This effect was not related to changes in the hemodynamics. The immunomodulatory effects of EPO were manifested as decreased levels of TNF-α and IL-10 in renal biopsies and TNF-α levels in plasma.

Feasibility and logistics of MRI before thrombolytic treatment

OBJECTIVES

The study analyzes feasibility and time-delays in Magnetic resonance imaging (MRI) based thrombolysis and estimate the impact of MRI on individual tissue plasminogen activator (rtPA) treatment.

MATERIALS AND METHODS

Feasibility of MRI and time logistics were prospectively recorded in patients referred with presumed acute stroke over a 2 year time period. Door-to-needle-times (DNT) were compared with those of patients treated with rtPA after conventional CT during the same time period, and to published open label studies.

RESULTS

We received 174 patients with presumed stroke. MRI was feasible in 141 of 161 (88%) of those requiring acute imaging. MRI supported the decision to treat 11 patients with mild symptoms or seizures, and not to treat four patients with extensive infarctions. Median 'door-to-needle time' (DNT) in MR scanned patients (70 min), did not differ significantly from DNT after conventional CT (n = 17, DNT = 66 min, P = 0.27) or the Safe Implementation of Thrombolysis in Stroke (SITS-MOST) registry (DNT = 68 min).

CONCLUSIONS

Magnetic resonance imaging can be performed in the majority of acute stroke patients without delaying treatment. MRI may affect decision making in a large proportion of patients.

[Imaging of the pathophysiology in acute stroke]

Recent developments in neuroimaging have changed the diagnostic aspect of acute stroke and improved our understanding of stroke pathophysiology. Both diffusion weighted MR imaging and CT are capable of detecting the infarcted volume damaged by cytotoxic edema. However, within six hours of stroke onset, DWI has both higher sensitivity and specificity than CT. Perfusion weighted MR imaging and perfusion CT can identify the tissue at risk surrounding the core of the infarct. CT and MR-angiography contribute important information concerning the intra and extracerebral arteries.

[Thrombolysis of apoplexy patients. A year's experience and results in Aarhus Hospital]

INTRODUCTION

Treatment of acute stroke with thrombolysis within three hours is a challenging aspect of the organization of state-of-the-art stroke care. Indication for thrombolysis is based on studies where CT was used as a diagnostic tool. MR-based techniques are in some aspects superior to CT, though the scan times are longer. In this study, the feasibility and effectiveness of MR-based thrombolysis was examined.

MATERIALS AND METHODS

Prospective registration of patient time delays, demographics, initial NIHSS (National Institute of Health Stroke Scale) and MR data for all patients referred to Aarhus Hospital with symptoms of acute stroke was done over a one-year period. For patients receiving thrombolysis, additional MR data, complications, NIHSS at follow-up (2 hours, 24 hours, 7 days and 3 months) and modified Rankin score at 3 months were recorded. Results were compared to the data in the international thrombolysis database (SITS-MOST).

RESULTS

During the period, 112 patients were referred and 86 were scanned using MR techniques. 22 patients received thrombolysis (17/5 after MR/CT). 54% of patients had a good outcome at 3 months (mRS = 0-1) compared to 34% in SITS-MOST (n.s). No symptomatic haemorrhages were recorded; mortality was 9% (13% in SITS-MOST). Treatment was not delayed compared to SITS-MOST despite the longer MR scan time.

CONCLUSION

Effective organization of treatment with thrombolysis using MR imaging is feasible. The MR techniques were beneficial in decision making and did not cause delay of treatment. Thrombolysis in this setup was as efficient with respect to outcome and complications as was that recorded in the SITS-MOST register.

Ischemic injury detected by diffusion imaging 11 minutes after stroke

A 78-year-old woman suffered a stroke inside a magnetic resonance scanner while being imaged because of a brief transient ischemic attack 2 hours earlier. Diffusion-weighted images obtained 11 minutes after stroke showed tissue injury not found on initial images. The data show early, abrupt diffusion changes in hypoperfused tissue, adding to our understanding of the progression of microstructural abnormalities in the hyperacute phase of stroke.