Serum albumin level as a predictor of outcome in traumatic brain injury: potential for treatment

The Geriatric Nutrition Risk Index Is Not a Prognostic Predictor for Postoperative Morbidity in Extremely Elderly Patients Undergoing Surgery for Proximal Femur Fractures

Background/Objectives: The geriatric nutrition risk index (GnRI) has been regarded as a useful predictor of morbidity and mortality in elderly patients. This study aimed to determine the use of the GnRI as a prognostic predictor in extremely elderly patients undergoing proximal femur fracture surgery and the usefulness of evaluation tools related to a patient's underlying disease and functional capacity in predicting the prognosis of extremely elderly patients. Methods: We analyzed 548 patients who had undergone surgery for proximal femur fracture caused by trauma, with an age of ≥80 years, without other accompanying trauma. Results: Body mass index (BMI) (OR, 1.077; 95% CI, 1.010-1.149; p = 0.023), serum albumin levels (0.389; 0.223-0.678; p = 0.001), and Charlson comorbidity index (CCI) (1.170; 1.014-1.349; p = 0.031) were determined to be predictors of morbidity in a multivariable regression analysis. The area under the curve (AUC) in the receiver operating characteristic curve of BMI was 0.565 (95% CI, 0.493-0.637; p = 0.065), and the optimal cut-off value could not be determined. The AUC of serum albumin was 0.647 (0.576-0.717; p < 0.001), and the optimal cut-off value was 3.65 g/dL (sensitivity, 72.2%; specificity, 52.7%). The AUC of the CCI was 0.648 (0.580-0.715; p < 0.001), and the optimal cut-off value was 6.5 (sensitivity, 63.3%; specificity, 61.4%). Conclusions: The GnRI was not a predictive factor for patient prognosis after proximal femur fractures in extreme elderly patients. Rather, serum albumin level and CCI, which reflect the patient's underlying comorbid conditions, were more useful in predicting in-hospital morbidity after proximal femur surgery in extremely elderly patients.

The Efficacy of Parenteral Nutrition and Enteral Nutrition Supports in Traumatic Brain Injury: A Systemic Review and Network Meta-Analysis

Background

Enteral nutrition (EN) is often used in patients with traumatic brain injury (TBI), but some studies have shown that EN has its disadvantages. However, it is not clear which nutritional support is appropriate to reduce mortality, improve prognosis, and improve nutritional status in patients with TBI. We performed this Bayesian network meta-analysis to evaluate the improvement of nutritional indicators and the clinical outcomes of patients with TBI.

Methods

We systematically searched PubMed, Embase, Cochrane Library, and Web of Science from inception until December 2021. All randomized controlled trials (RCTs) which compared the effects of different nutritional supports on clinical outcomes and nutritional indicators in patients with TBI were included. The co-primary outcomes included mortality and the value of serum albumin. The secondary outcomes were nitrogen balance, the length of study (LOS) in the ICU, and feeding-related complications. The network meta-analysis was performed to adjust for indirect comparison and mixed treatment analysis.

Results

7 studies enroll a total of 456 patients who received different nutritional supports including parenteral nutrition (PN), enteral nutrition (EN), and PN + EN. No effects on in-hospital mortality (Median RR = 1.06, 95% Crl = 0.12 to 1.77) and the value of 0-1 days of serum albumin were found between the included regimens. However, the value of 11-13 days of serum albumin of EN was better than that of PN (WMD = -4.95, 95% CI = -7.18 to -2.72, P < 0.0001, I ² = 0%), and 16-20 days of serum albumin of EN + PN was better than that of EN (WMD = -7.42, 95% CI = -14.51 to -0.34, P=0.04, I ² = 90%). No effects on the 5-7 day nitrogen balance were found between the included regimens. In addition, the complications including pneumonia and sepsis have no statistical difference between EN and PN. EN was superior to PN in terms of LOS in the ICU and the incidence rate of stress ulcers. Although the difference in indirect comparisons between the included regimens was not statistically significant, the results showed that PN seemed to rank behind other regimens, and the difference between them was extremely small.

Conclusion

Available evidence suggests that EN + PN appears to be the most effective strategy for patients with TBI in improving clinical outcomes and nutritional support compared with other nutritional supports. Further trials are required.

Mismatch between Tissue Partial Oxygen Pressure and Near-Infrared Spectroscopy Neuromonitoring of Tissue Respiration in Acute Brain Trauma: The Rationale for Implementing a Multimodal Monitoring Strategy

The brain tissue partial oxygen pressure (PbtO₂) and near-infrared spectroscopy (NIRS) neuromonitoring are frequently compared in the management of acute moderate and severe traumatic brain injury patients; however, the relationship between their respective output parameters flows from the complex pathogenesis of tissue respiration after brain trauma. NIRS neuromonitoring overcomes certain limitations related to the heterogeneity of the pathology across the brain that cannot be adequately addressed by local-sample invasive neuromonitoring (e.g., PbtO₂ neuromonitoring, microdialysis), and it allows clinicians to assess parameters that cannot otherwise be scanned. The anatomical co-registration of an NIRS signal with axial imaging (e.g., computerized tomography scan) enhances the optical signal, which can be changed by the anatomy of the lesions and the significance of the radiological assessment. These arguments led us to conclude that rather than aiming to substitute PbtO₂ with tissue saturation, multiple types of NIRS should be included via multimodal systemic- and neuro-monitoring, whose values then are incorporated into biosignatures linked to patient status and prognosis. Discussion on the abnormalities in tissue respiration due to brain trauma and how they affect the PbtO₂ and NIRS neuromonitoring is given.

Feature engineering combined with 1-D convolutional neural network for improved mortality prediction

Objectives

The appropriate care for patients admitted in Intensive care units (ICUs) is becoming increasingly prominent, thus recognizing the use of machine learning models. The real-time prediction of mortality of patients admitted in ICU has the potential for providing the physician with the interpretable results. With the growing crisis including soaring cost, unsafe care, misdirected care, fragmented care, chronic diseases and evolution of epidemic diseases in the domain of healthcare demands the application of automated and real-time data processing for assuring the improved quality of life. The intensive care units (ICUs) are responsible for generating a wealth of useful data in the form of Electronic Health Record (EHR). This data allows for the development of a prediction tool with perfect knowledge backing.

Method

We aimed to build the mortality prediction model on 2012 Physionet Challenge mortality prediction database of 4,000 patients admitted in ICU. The challenges in the dataset, such as high dimensionality, imbalanced distribution and missing values, were tackled with analytical methods and tools via feature engineering and new variable construction. The objective of the research is to utilize the relations among the clinical variables and construct new variables which would establish the effectiveness of 1-Dimensional Convolutional Neural Network (1-D CNN) with constructed features.

Results

Its performance with the traditional machine learning algorithms like XGBoost classifier, Light Gradient Boosting Machine (LGBM) classifier, Support Vector Machine (SVM), Decision Tree (DT), K-Neighbours Classifier (K-NN), and Random Forest Classifier (RF) and recurrent models like Long Short-Term Memory (LSTM) and LSTM-attention is compared for Area Under Curve (AUC). The investigation reveals the best AUC of 0.848 using 1-D CNN model.

Conclusion

The relationship between the various features were recognized. Also, constructed new features using existing ones. Multiple models were tested and compared on different metrics.

Human albumin solutions in intensive care: A review

Albumin plays a key role in the critically ill patient acting as a prognostic marker and as a therapy in the form of human albumin solutions. However, the use of human albumin solution has varied over time with notable differences between health systems. Whilst its use is widely accepted for some clinical indications, its role has not always been clear in the critically ill and has been found to be harmful in some cohorts. Numerous studies have showed conflicting results and critical care clinicians have not always been guided by robust evidence. Nonetheless, at present the use of human albumin solution appears to be increasing again in the United Kingdom. Below, we discuss the latest evidence base for its use in critically ill patients.

A Preliminary Cohort Study Assessing Routine Blood Analyte Levels and Neurological Outcome after Spinal Cord Injury

There is increasing interest in the identification of biomarkers that could predict neurological outcome following a spinal cord injury (SCI). Although initial American Spinal Injury Association (ASIA) Impairment Scale (AIS) grade is a good indicator of neurological outcome, for the patient and clinicians, an element of uncertainty remains. This preliminary study aimed to assess the additive potential of routine blood analytes following principal component analysis (PCA) to develop prognostic models for neurological outcome following SCI. Routine blood and clinical data were collected from SCI patients (n = 82) and PCA used to reduce the number of blood analytes into related factors. Outcome neurology was obtained from AIS scores at 3 and 12 months post-injury, with motor (AIS and total including all myotomes) and sensory (AIS, touch and pain) abilities being assessed individually. Multiple regression models were created for all outcome measures. Blood analytes relating to “liver function” and “acute inflammation and liver function” factors were found to significantly increase prediction of neurological outcome at both 3 months (touch, pain, and AIS sensory) and at 1 year (pain, R² increased by 0.025 and total motor, R² increased by 0.016). For some models “liver function” and “acute inflammation and liver function” factors were both significantly predictive, with the greatest combined R² improvement of 0.043 occurring for 3 month pain prediction. These preliminary findings support ongoing research into the use of routine blood analytes in the prediction of neurological outcome in SCI patients.

Point-of-Care Ultrasound Abnormalities in Late-Onset Severe Preeclampsia: Prevalence and Association With Serum Albumin and Brain Natriuretic Peptide

BACKGROUND

Pilot studies applying point-of-care ultrasound (POCUS) in preeclampsia indicate the presence of pulmonary interstitial edema, cerebral edema, and cardiac dysfunction. Laboratory markers of oncotic pressure (albumin) and cardiac dysfunction (brain natriuretic peptide [BNP]) may be abnormal, but the clinical application remains unclear. We investigated the prevalence of pulmonary interstitial syndrome (PIS), cardiac dysfunction, and increased optic nerve sheath diameter (ONSD) in late-onset preeclampsia with severe features. The primary aim was to examine the association between PIS or ONSD and maternal serum albumin level. The secondary aims were to explore the association between cardiac dysfunction and PIS, ONSD, BNP, and serum albumin level and between POCUS-derived parameters and a suspicious or pathological cardiotocograph.

METHODS

Ninety-five women were enrolled in this prospective observational cohort study. A POCUS examination of lungs, heart, and ONSD was performed. PIS was defined as a bilateral B-line pattern on lung ultrasound and diastolic dysfunction according to an algorithm of the American Society of Echocardiography. ONSD >5.8 mm was interpreted as compatible with raised intracranial pressure (>20 mm Hg). Serum BNP and albumin levels were also measured.

RESULTS

PIS, diastolic dysfunction, systolic dysfunction, and raised left ventricular end-diastolic pressure (LVEDP) were present in 23 (24%), 31 (33%), 9 (10%), and 20 (25%) women, respectively. ONSD was increased in 27 (28%) women. Concerning the primary outcome, there was no association between albumin level and PIS (P = .4) or ONSD (P = .63). With respect to secondary outcomes, there was no association between albumin level and systolic dysfunction (P = .21) or raised LVEDP (P = .44). PIS was associated with diastolic dysfunction (P = .02) and raised LVEDP (P = .009; negative predictive value, 85%). BNP level was associated with systolic (P < .001) and diastolic dysfunction (P = .003) and LVEDP (P = .007). No association was found between POCUS abnormalities and a suspicious/pathological cardiotocograph (P = .07).

CONCLUSIONS

PIS, diastolic dysfunction, and increased ONSD were common in preeclampsia with severe features. Cardiac ultrasound abnormalities may be more useful than albumin levels in predicting PIS. The absence of PIS may exclude raised LVEDP. The further clinical relevance of PIS and raised ONSD remains to be established. BNP level was associated with cardiac ultrasound abnormalities. Although this study was not designed to directly influence clinical management, the findings suggest that POCUS may serve as a useful adjunct to clinical examination for the obstetric anesthesiologist managing these complex patients.

Serum Albumin Predicts Long-Term Neurological Outcomes After Acute Spinal Cord Injury

Background. There is a need to identify reliable biomarkers of spinal cord injury recovery for clinical practice and clinical trials. Objective. Our objective was to correlate serum albumin levels with spinal cord injury neurological outcomes. Methods. We performed a secondary analysis of patients with traumatic spinal cord injury (n = 591) participating in the Sygen clinical trial. Serum albumin concentrations were obtained as part of routine blood chemistry analysis, at trial entry (24-72 hours), 1, 2, and 4 weeks after injury. The primary outcomes were “marked recovery” and lower extremity motor scores, derived from the International Standards for the Neurological Classification of Spinal Cord Injury. Data were analyzed with multivariable logistic and linear regression to adjust for potential confounders. Results. Serum albumin was significantly associated with spinal cord injury neurological outcomes. Higher serum albumin concentrations at 1, 2, and 4 weeks were associated with higher 52-week lower extremity motor score. Similarly, the odds of achieving “marked neurological recovery” was greater for individuals with higher serum albumin concentrations. The association between serum albumin concentrations and neurological outcomes was independent of initial injury severity, treatment with GM-1, and polytrauma. Conclusions. In spinal cord injury, serum albumin is an independent marker of long-term neurological outcomes. Serum albumin could serve as a feasible biomarker for prognosis at the time of injury and stratification in clinical trials.

Critical Evaluation of the Lund Concept for Treatment of Severe Traumatic Head Injury, 25 Years after Its Introduction

When introduced in 1992, the Lund concept (LC) was the first complete guideline for treatment of severe traumatic brain injury (s-TBI). It was a theoretical approach, based mainly on general physiological principles-i.e., of brain volume control and optimization of brain perfusion and oxygenation of the penumbra zone. The concept gave relatively strict outlines for cerebral perfusion pressure, fluid therapy, ventilation, sedation, nutrition, the use of vasopressors, and osmotherapy. The LC strives for treatment of the pathophysiological mechanisms behind symptoms rather than just treating the symptoms. The treatment is standardized, with less need for individualization. Alternative guidelines published a few years later (e.g., the Brain Trauma Foundation guidelines and European guidelines) were mainly based on meta-analytic approaches from clinical outcome studies and to some extent from systematic reviews. When introduced, they differed extensively from the LC. We still lack any large randomized outcome study comparing the whole concept of BTF guidelines with other guidelines including the LC. From that point of view, there is limited clinical evidence favoring any of the s-TBI guidelines used today. In principle, the LC has not been changed since its introduction. Some components of the alternative guidelines have approached those in the LC. In this review, I discuss some important principles of brain hemodynamics that have been lodestars during formulation of the LC. Aspects of ventilation, nutrition, and temperature control are also discussed. I critically evaluate the most important components of the LC 25 years after its introduction, based on hemodynamic principles and on the results of own an others experimental and human studies that have been published since then.

Traumatic brain injury and palliative care: a retrospective analysis of 49 patients receiving palliative care during 2013-2016 in Turkey

Traumatic brain injury (TBI), which is seen more in young adults, affects both patients and their families. The need for palliative care in TBI and the limits of the care requirement are not clear. The aim of this study was to investigate the length of stay in the palliative care center (PCC), Turkey, the status of patients at discharge, and the need for palliative care in patients with TBI. The medical records of 49 patients with TBI receiving palliative care in PCC during 2013–2016 were retrospectively collected, including age and gender of patients, the length of stay in PCC, the cause of TBI, diagnosis, Glasgow Coma Scale score, Glasgow Outcome Scale score, Karnofsky Performance Status score, mobilization status, nutrition route (oral, percutaneous endoscopic gastrostomy), pressure ulcers, and discharge status. These patients were aged 45.4 ± 20.2 years. The median length of stay in the PCC was 34.0 days. These included TBI patients had a Glasgow Coma Scale score ≤ 8, were not mobilized, received tracheostomy and percutaneous endoscopic gastrostomy nutrition, and had pressure ulcers. No difference was found between those who were discharged to their home or other places (rehabilitation centre, intensive care unit and death) in respect of mobilization, percutaneous endoscopic gastrostomy, tracheostomy and pressure ulcers. TBI patients who were followed up in PCC were determined to be relatively young patients (45.4 ± 20.2 years) with mobilization and nutrition problems and pressure ulcer formation. As TBI patients have complex health conditions that require palliative care from the time of admittance to intensive care unit, provision of palliative care services should be integrated with clinical applications.

Influence of undernutrition at admission on clinical outcomes in patients with acute myocardial infarction

BACKGROUND

Although the effect of overweight or obesity on clinical outcomes in patients with acute myocardial infarction (MI) has been reported, the effect of undernutrition is not as well understood. Therefore, we investigated whether acute MI patients frequently present with undernutrition, and whether this influences poor clinical outcomes.

METHODS AND RESULTS

Using the Korea Acute Myocardial Infarction Registry database, we screened initial data on acute MI patients admitted within 48h of symptom onset to a tertiary university hospital between November 1, 2011 and May 31, 2015. We then assessed nutritional status at admission, using the Geriatric Nutritional Risk Index (GNRI). Of a total of 2251 patients, there were 1585 (70.4%) men, and mean age was 65.0±12.8 years. Based on GNRI score, undernutrition at admission was present in 409 (18.2%) patients. Multiple logistic regression analysis found undernutrition to be an independent factor influencing post-MI complications [odds ratio (OR), 2.13; 95% confidence interval (CI), 1.61-2.84; p<0.001], after adjusting for age, sex, hypertension, diabetes, hyperlipidemia, previous stroke, smoking, diagnosis, number of involved vessel lesions, Killip class, atrial fibrillation, baseline blood pressure, hemoglobin, creatine kinase-MB, creatinine, performance of percutaneous coronary intervention, reperfusion time, recanalization, and use of antithrombotics. Undernutrition was also an important factor influencing in-hospital death (OR, 2.48; 95% CI, 1.55-3.95; p<0.001), after adjusting for all potential factors by univariate analysis.

CONCLUSIONS

Nutritional status is a significant prognostic factor in clinical outcomes after MI during hospitalization. Therefore, nutritional assessment and intervention, especially for undernourished MI patients, should be considered.

Nutritional parameters predicting pressure ulcers and short-term mortality in patients with minimal conscious state as a result of traumatic and non-traumatic acquired brain injury

BACKGROUND

The association between malnutrition and worse outcomes as pressure ulcers and mortality is well established in a variety of setting. Currently none investigation was conducted in patients with long-term consequences of the acquired brain injury in which recovery from brain injury could be influenced by secondary complications. The aim of this study was to investigate the association between various nutritional status parameters (in particular albumin) and pressure ulcers formation and short-term mortality in minimal conscious state patients.

METHODS

In this prospective, observational study of 5-months duration, a 30 patients sample admitted to a Neurological Institute was considered. All patients underwent a complete medical examination. Anthropometric parameters like mid-arm circumference and mid-arm muscle circumference and nutritional parameters as serum albumin and blood hemoglobin concentration were assessed.

RESULTS

At univariate and logistic regression analysis, mid-arm circumference (p = 0.04; beta = -0.89), mid-arm muscle circumference (p = 0.050; beta = -1.29), hemoglobin (p = 0.04, beta -1.1) and albumin (p = 0.04, beta -7.91) were inversely associated with pressure ulcers. The area under the ROC curve for albumin to predict sores was 0.76 (p = 0.02) and mortality was 0.83 (p = 0.03). Patient with lower albumin had significantly higher short-term mortality than those with higher serum albumin (p = 0.03; χ(2) test = 6.47).

CONCLUSION

Albumin, haemoglobin and mid-arm circumference are inversely associated with pressure ulcers. Albumin is a prognostic index in MCS patients. Since albumin and haemoglobin could be affected by a variety of factors, this association suggests to optimize nutrition and investigate on other mechanism leading to mortality and pressure ulcers.

Hypoalbuminemia at admission is associated with increased incidence of in-hospital complications in geriatric trauma patients

BACKGROUND

Elderly patients are at an increased risk of protein-energy malnutrition (PEM) which increases the risk of morbidity/mortality. We evaluated the association between hypoalbuminemia at the time of emergency department (ED) admission and in-hospital complications among geriatric trauma patients.

METHODS

This was an ambidirectional cohort study of geriatric (≥55 years) trauma patients treated at a Level I trauma center between May 2013 and March 2014. The exposure of interest was albumin level at ED admission (<3.6 g/dL [PEM] or ≥3.6 g/dL (No PEM)]. The outcome of interest was 30-day incidence of complications.

RESULTS

A total of 130 patients met study eligibility. Of these, 85 (65%) patients were in the PEM group. After adjusting for tube feeding and injury severity score, PEM at admission was associated with a 2-fold increase in the risk of 30-day overall hospital complications (hazard ratio 2.1, 95% confidence interval 1.1 to 3.8).

CONCLUSION

Serum albumin level at ED admission, but not prealbumin level, is a significant predictor of in-hospital complications in geriatric trauma patients.

Persistent hypoalbuminemia is a predictor of outcome in cervical spinal cord injury

BACKGROUND CONTEXT

Hypoalbuminemia is associated with increased morbidity and mortality in various clinical settings and several major diseases. Albumin has multiple physiologic properties that could be beneficial in central nervous system injury.

PURPOSE

We sought to determine if albumin is associated with patient outcome after cervical spinal cord injury by conducting a retrospective analysis.

STUDY DESIGN/SETTING

A retrospective study of cervical spinal cord injury (CSCI) patients was conducted to investigate if serum albumin levels and other characteristics influence outcome (mechanical ventilation and death).

PATIENT SAMPLE

A total of 178 consecutive patients were included in the present study.

OUTCOME MEASURES

Demographic data were recorded, including age, gender, smoking history, time from injury to admission, severity of neurologic injury, neurologic level of lesion, mechanism of neurologic injury, Glasgow Coma Score, vitals in the Orthopedic Department, the occurrence of early surgical intervention (48 hours after injury), and daily serum albumin levels.

METHODS

No funds were received in support of this work. No specific conflicts of interest were involved in this article. Serum albumin levels and other characteristics known to influence outcome were included in univariate statistical analyses and the multiple logistic regression model to analyze the relationship with mechanical ventilation and death after cervical injury.

RESULTS

Approximately 41.0% (73/178) of patients had complete spinal cord injury (ASIA A), 36.5% (65/178) of patients required mechanical ventilation, and 8.4% (15/178) of patients died within the first month after injury. Albumin remained lower than 30 g/L for a period of time (≥5 days) in patients with an unfavorable outcome (patients requiring mechanical ventilation or who had died). Multiple logistic regression analysis identified age (>50 years), persistent hypoalbuminemia (<30 g/L and ≥5 days), C5 and above neurologic injury, and ASIA A as predictors for mechanical ventilation. In addition, persistent hypoalbuminemia, ASIA A, and C4 and above neurologic injury were significantly associated with death.

CONCLUSION

Similar to the ASIA scale and neurologic level, persistent hypoalbuminemia seems to be an independent predictor of outcome in patients with CSCI. Thus, a randomized trial assessing albumin in the treatment of cervical spinal cord injury is warranted.

Albumin administration in the acutely ill: what is new and where next?

Albumin solutions have been used worldwide for the treatment of critically ill patients since they became commercially available in the 1940s. However, their use has become the subject of criticism and debate in more recent years. Importantly, all fluid solutions have potential benefits and drawbacks. Large multicenter randomized studies have provided valuable data regarding the safety of albumin solutions, and have begun to clarify which groups of patients are most likely to benefit from their use. However, many questions remain related to where exactly albumin fits within our fluid choices. Here, we briefly summarize some of the physiology and history of albumin use in intensive care before offering some evidence-based guidance for albumin use in critically ill patients.

Serum albumin and prealbumin predict the poor outcome of traumatic brain injury

Background

Serum albumin and prealbumin are both negative acute-phase reactants, and usually at low levels in stress. We aim to determine their predictive values for poor outcome of traumatic brain injury (TBI).

Methods

A total of 326 patients of TBI were enrolled and followed-up by telephone 6 months after discharge. They were divided into a favorable group (GOS: 3 to 5) and an unfavorable group (GOS: 1 to 2). Serum albumin and prealbumin were measured from vein blood within 24 h after admission.

Results

Ninety one (27.9%) patients were with poor outcome (GOS: 1 to 2). The unfavorable group had lower albumin and prealbumin (P<0.001). Albumin and prealbumin were both positively correlated with GCS (r = 0.489, P<0.001; r = 0.222, P<0.001, respectively) and GOS (r = 0.518, P<0.001; r = 0.314, P<0.001, respectively). After adjustment for confounding factors, the odds ratios of albumin and prealbumin were 0.866, 95% CI: 0.829 to 0.904 and 0.990, 95% CI: 0.985 to 0.995, respectively. In subgroup of GCS≤8 (n = 101), the crude and adjusted odds ratios of serum albumin were both statistically significant (P = 0.027, P = 0.033, respectively), while prealbumin were not (P = 0.553, P = 0.576, respectively). The AUC of albumin for predicting poor outcome was 0.762, 95% CI: 0.712 to 0.807, which was significantly higher than that of prealbumin (0.664, 95% CI: 0.610 to 0.715). In analyses of all patients and subgroup of GCS≤8, the AUCs of serum albumin were both significantly higher than those of prealbumin (P = 0.001, P = 0.045, respectively).

Conclusions

Both serum albumin and prealbumin could predict the poor outcome of TBI, but the former is much better, especially, in patients with severe TBI.

Multivariate outcome prediction in traumatic brain injury with focus on laboratory values

Traumatic brain injury (TBI) is a major cause of morbidity and mortality. Identifying factors relevant to outcome can provide a better understanding of TBI pathophysiology, in addition to aiding prognostication. Many common laboratory variables have been related to outcome but may not be independent predictors in a multivariate setting. In this study, 757 patients were identified in the Karolinska TBI database who had retrievable early laboratory variables. These were analyzed towards a dichotomized Glasgow Outcome Scale (GOS) with logistic regression and relevance vector machines, a non-linear machine learning method, univariately and controlled for the known important predictors in TBI outcome: age, Glasgow Coma Score (GCS), pupil response, and computed tomography (CT) score. Accuracy was assessed with Nagelkerke's pseudo R². Of the 18 investigated laboratory variables, 15 were found significant (p<0.05) towards outcome in univariate analyses. In contrast, when adjusting for other predictors, few remained significant. Creatinine was found an independent predictor of TBI outcome. Glucose, albumin, and osmolarity levels were also identified as predictors, depending on analysis method. A worse outcome related to increasing osmolarity may warrant further study. Importantly, hemoglobin was not found significant when adjusted for post-resuscitation GCS as opposed to an admission GCS, and timing of GCS can thus have a major impact on conclusions. In total, laboratory variables added an additional 1.3-4.4% to pseudo R².

Change in plasma gelsolin level after traumatic brain injury

BACKGROUND

Plasma gelsolin depletion has been associated with poor outcome of critically ill patients. However, there is a paucity of data available on circulating plasma gelsolin concentration in traumatic brain injury (TBI). Thus, we sought to investigate change in plasma gelsolin level after TBI and to evaluate its relation with disease outcome.

METHODS

Fifty healthy controls and 94 patients with acute severe TBI were included. Plasma samples were obtained on admission and at days 1, 2, 3, 5, and 7. Its concentration was measured by enzyme-linked immunosorbent assay.

RESULTS

Twenty-six patients (27.7%) died from TBI in a month. After TBI, plasma gelsolin level in patients decreased during the 6-hour period immediately, was at the nadir in 24 hours, increased gradually thereafter, and was substantially lower than that in healthy controls during the 7-day period. A multivariate analysis showed plasma gelsolin level was an independent predictor for 1-month mortality (odds ratio, 0.941; 95% confidence interval, 0.895– 0.989; p = 0.017) and positively associated with Glasgow Coma Scale (GCS) score (t = 6.538, p 0.001). A receiver operating characteristic curve identified that a baseline plasma gelsolin level 52.7 mg/L predicted 1-month mortality with 88.5% sensitivity and 79.4% specificity (area under the curve, 0.869; 95%confidence interval, 0.783– 0.930). The predictive value of the gelsolin concentration was thus similar to that of GCS scores (p =0.185). However, gelsolin did not statistically significantly improve the area under the curve of GCS scores (p = 0.517).

CONCLUSIONS

Decreased plasma gelsolin level is associated with GCS scores and an independent prognostic marker of mortality after TBI. Reversing plasma gelsolin deficiency may be an effective treatment for TBI.

Polynitroxyl albumin and albumin therapy after pediatric asphyxial cardiac arrest: effects on cerebral blood flow and neurologic outcome

Postresuscitation cerebral blood flow (CBF) disturbances and generation of reactive oxygen species likely contribute to impaired neurologic outcome after pediatric cardiac arrest (CA). Hence, we determined the effects of the antioxidant colloid polynitroxyl albumin (PNA) versus albumin or normal saline (NS) on CBF and neurologic outcome after asphyxial CA in immature rats. We induced asphyxia for 9 minutes in male and female postnatal day 16 to 18 rats randomized to receive PNA, albumin, or NS at resuscitation from CA or sham surgery. Regional CBF was measured serially from 5 to 150 minutes after resuscitation by arterial spin-labeled magnetic resonance imaging. We assessed motor function (beam balance and inclined plane), spatial memory retention (water maze), and hippocampal neuronal survival. Polynitroxyl albumin reduced early hyperemia seen 5 minutes after CA. In contrast, albumin markedly increased and prolonged hyperemia. In the delayed period after resuscitation (90 to 150 minutes), CBF was comparable among groups. Both PNA- and albumin-treated rats performed better in the water maze versus NS after CA. This benefit was observed only in males. Hippocampal neuron survival was similar between injury groups. Treatment of immature rats with PNA or albumin resulted in divergent acute changes in CBF, but both improved spatial memory retention in males after asphyxial CA.

Molecular biomarkers of epileptogenesis

The heterogeneity of epilepsy syndromes and pathologies creates a great challenge for the search for biomarkers. Not surprisingly, identification of a marker that is specific and sensitive for a given epileptogenic pathology remains an unmet need. There have, however, been several studies of major epileptogenic etiologies like traumatic brain injury that aimed to identify molecular markers in blood and cerebrospinal fluid that predict outcome, by using proteomics and metabolomics. Unfortunately, epileptogenesis has not been analyzed as an outcome measure. Another question to be explored is whether a palette of molecular markers is needed, rather than a single molecule, with each marker probing a different component of epileptogenic pathology. Further, perhaps multiple biomarker platforms (e.g., imaging, proteomics, electrophysiology) should be used in combination and/or in a defined temporal sequence.

In my opinion: serum albumin should be maintained during neurocritical care

Hypoalbuminemia is common among critically ill/injured patients and is strongly associated with increased morbidity and mortality in the patients with and without neurological conditions. Normal serum albumin is important as the primary intravascular antioxidant, in transporting a variety of hormones, medications and electrolytes, in providing colloid osmotic pressure during trans-compartmental fluid movement, in enhancing organ and tissue blood flow, and in supporting acid-base balance. Studies of albumin administration during intravascular resuscitation have not addressed potential longer term benefits to sustaining serum albumin concentrations during critical care. Evidence for such benefit is present although additional prospective studies are needed.

Prediction of outcome in severe traumatic brain injury

PURPOSE OF REVIEW

Prognostic models for predicting outcome after severe traumatic brain injury (TBI) may be useful in several areas. However, established risk prediction models for general critical illness show significant limitations in neurotrauma. Development of specific risk prediction models for TBI has been difficult due to the variability of injury, which predicates a large sample for construction of robust models. Previous development of prognostic models for TBI has suffered from small sample sizes, poor study design and follow up, difficulty in application to clinical practice, limited inclusion of patients from low income countries, and lack of external validation.

RECENT FINDINGS

This situation has changed substantially in the last year with the development and validation of two new risk prediction models based on large datasets.The Corticosteroid Randomization after Significant Head Injury (CRASH) trial and the International Mission on Prognosis and Analysis of Clinical Trials in TBI (IMPACT) databases have been used to create prediction with or without computed tomography data, and been cross validated. In addition, the CRASH database was used to develop models for low/middle income countries.

SUMMARY

The outcome prediction models that have evolved from these databases are undergoing further refinement and validation, and it is likely that these advances will prove valuable in training clinicians, counselling patients' families, auditing unit performance, designing better clinical trials, and rational allocation of resources.