Fluid therapy and the use of albumin in the treatment of severe traumatic brain injury

Association Between Postoperative Decrease of Albumin and Outcomes in Patients Undergoing Craniotomy for Brain Tumors

BACKGROUND

Serum albumin reflects nutritional status and is associated with postoperative complications and mortality. Delta albumin (ΔAlb), defined as the difference between preoperative and lowest postoperative levels, could predict complications and mortality, even with postoperative levels above 30 g/L prompting albumin infusions. This study aimed to assess how ΔAlb relates to outcomes in craniotomy patients with brain tumors.

METHODS

This retrospective study screened patients diagnosed with a brain tumor who underwent cerebral surgery from a single Chinese hospital between December 2010 and April 2021. Patients were divided into 4 groups based on their ΔAlb levels: <5 g/L (normal), 5-9.9 g/L (mild ΔAlb), 10-14.9 g/L (moderate ΔAlb), and ≥15 g/L (severe ΔAlb). The primary outcome was postoperative 30-day mortality.

RESULTS

Among the 9660 patients undergoing craniotomy for brain tumors, the median ΔAlb level after craniotomy was 7.3 g/L. ΔAlb was associated with increased postoperative 30-day mortality; odds ratios for mild, moderate, and severe ΔAlb were 1.93 (95% confidence interval [CI], 1.17-3.18, P = 0.01), 2.21 (95% CI, 1.28-3.79, P = 0.004), and 7.26 (95% CI, 4.19-12.58, P < 0.01), respectively. Significantly, ΔAlb >5 g/L was found to have a strong association with a higher risk of mortality, even when the nadir Alb remained greater than 30 g/L (odds ratio, 1.84; 95% CI, 1.13-3.00, P = 0.014).

CONCLUSIONS

Among patients undergoing craniotomy for brain tumor resection, a mild degree of ΔAlb was associated with increased 30-day mortality, even if the nadir Alb remained greater than 30 g/L. Moreover, ΔAlb was associated with postoperative complications and longer lengths of stay.

Liver fibrosis score is associated with the mortality of traumatic brain injury patients

The fibrosis-4 score is a marker of liver fibrosis and has been confirmed to be associated with the prognosis of various diseases. There is no study exploring the prognostic value of the fibrosis-4 score in traumatic brain injury (TBI) patients. We design this study to explore the association between the fibrosis-4 score and mortality from TBI. TBI patients from the Medical Information Mart for Intensive Care-III database were extracted for the study. Univariate and multivariate logistic regressions were sequentially performed to analyze the association between fibrosis-4 and mortality in TBI. The area under the receiver operating characteristic curve (AUC) was drawn to evaluate the prognostic value of fibrosis-4 and other scores. A total of 1018 TBI patients were included, with a 30-day mortality of 24.2%. Non-survivors had older age, lower Glasgow Coma Scale (GCS), and higher injury severity score (ISS) than survivors. The aspartate aminotransferase platelet ratio index (APRI) and fibrosis-4 score were significantly higher in non-survivors. Univariate logistic regression showed that age, GCS, ISS, white blood cell, hemoglobin, fibrosis-4 score, subarachnoid hemorrhage, and anticoagulants were associated with the mortality of TBI patients. Multivariate logistic regression presented that age, GCS, ISS, fibrosis-4 score, subarachnoid hemorrhage, and anticoagulants were independent risk factors of mortality in TBI patients after adjusting for confounding effects. The AUC of the GCS, ISS, APRI, and fibrosis-4 score for predicting mortality was 0.711, 0.625, 0.592, and 0.627, respectively. Composed of age, GCS, ISS, fibrosis-4 score, subarachnoid hemorrhage, and anticoagulants, the predictive model had the highest AUC value of 0.790. The fibrosis-4 score is an independent risk factor for mortality in TBI. The model incorporating fibrosis-4 performs well in predicting the prognosis of TBI patients.

Use of Hyperoncotic Human Albumin Solution in Severe Traumatic Brain Injury Revisited-A Narrative Review and Meta-Analysis

A significant proportion of patients with a severe traumatic brain injury (TBI) have hypoalbuminemia and require fluid resuscitation. Intravenous fluids can have both favorable and unfavorable consequences because of the risk of hyperhydration and hypo- or hyperosmolar conditions, which may affect the outcome of a TBI. Fluid resuscitation with human albumin solution (HAS) corrects low serum albumin levels and aids in preserving euvolemia in non-brain-injured intensive care units and in perioperative patients. However, the use of HAS for TBI remains controversial. In patients with TBI, the infusion of hypooncotic (4%) HAS was associated with adverse outcomes. The side effects of 4% HAS and the safety and efficacy of hyperoncotic (20-25%) HAS used in the Lund concept of TBI treatment need further investigation. A nonsystematic review, including a meta-analysis of controlled clinical trials, was performed to evaluate hyperoncotic HAS in TBI treatment. For the meta-analysis, the MEDLINE and EMBASE Library databases, as well as journal contents and reference lists, were searched for pertinent articles up to March 2021. Four controlled clinical studies involving 320 patients were included. The first was a randomized trial. Among 165 patients treated with hyperoncotic HAS, according to the Lund concept, 24 (14.5%) died vs. 59 out of 155 control patients (38.1%). A Lund concept intervention using hyperoncotic HAS was associated with a significantly reduced mortality (p = 0.002). Evidence of the beneficial effects of fluid management with hyperoncotic HAS on mortality in patients with TBI is at a high risk of bias. Prospective randomized controlled trials are required, which could lead to changes in clinical practice recommendations for fluid management in patients with TBI.

The Perioperative Use of Albumin

Human serum albumin (HSA) is the predominant product of hepatic protein synthesis and one of the more abundant plasma proteins. HSA is a monomeric multidomain macromolecule, representing the main determinant of plasma oncotic pressure and the main modulator of fluid distribution between body compartments. HSA displays an essential role in maintaining the integrity of the vascular barrier. HSA is the most important antioxidant capacity of human plasma, in addition to its ability to protect the body from the harmful effects of heavy metals such as iron and copper and reduce their ability to produce reactive oxygen radicals. HSA is the main depot for nitric oxide (NO) transport in the blood. HSA represents the main carrier for fatty acids, affects pharmacokinetics of many drugs, and provides the metabolic modification of some drugs and displays pseudo-enzymatic properties. HSA has been widely used successfully for more than 50 years in many settings of perioperative medicine including hypovolemia, shock, burns, surgical blood loss, sepsis, and acute respiratory distress syndrome (ARDS). Recently, the use of HSA has shown a promising neuroprotective effect in patients with subarachnoid hemorrhage. The most recent evidence-based functions and uses of HSA in the perioperative period are reviewed in this chapter.

Cerebral and extracerebral vulnerability to hypoxic insults after diffuse traumatic brain injury in rats

The post-traumatic brain vulnerability suggests that after traumatic brain injury (TBI), the brain may be more susceptible to posttraumatic hypoxic insults. This concept could be extended to 'peripheral' organs, as non-neurologic organ failure is common after TBI. This study aims to characterize and quantify cerebral and extracerebral tissue hypoxia with pimonidazole resulting from a standardized hypoxia-hypotension (HH) phase occurring after a diffuse experimental TBI in rats. Rats were allocated to Sham (n=5), TBI (n=7), HH (n=7) and TBI+HH (n=7) groups. Then, pimonidazole was injected and brain, liver, heart and kidneys were analysed. In the cerebral cortex, post-treatment hypoxia was higher in TBI+HH group than Sham group (p=0.003), HH group (p=0.003) and TBI group (p=0.002). Large trends in thalamus, hippocampus and striatum for the TBI+HH group compared to the other groups were observed. For the heart and liver, the 4 groups were comparable. For the kidneys, post-treatment hypoxia was higher in the TBI group compared to the Sham and HH groups, but not more than TBI+HH group. This study reveals that a posttraumatic hypoxic insult occurring after a severe TBI has major hypoxic consequences on brain structures. However, TBI by itself appears to induce renal hypoxia that is not enhanced by posttraumatic hypoxic insult.

Fluid management of the neurological patient: a concise review

Maintenance fluids in critically ill brain-injured patients are part of routine critical care. Both the amounts of fluid volumes infused and the type and tonicity of maintenance fluids are relevant in understanding the impact of fluids on the pathophysiology of secondary brain injuries in these patients. In this narrative review, current evidence on routine fluid management of critically ill brain-injured patients and use of haemodynamic monitoring is summarized. Pertinent guidelines and consensus statements on fluid management for brain-injured patients are highlighted. In general, existing guidelines indicate that fluid management in these neurocritical care patients should be targeted at euvolemia using isotonic fluids. A critical appraisal is made of the available literature regarding the appropriate amount of fluids, haemodynamic monitoring and which types of fluids should be administered or avoided and a practical approach to fluid management is elaborated. Although hypovolemia is bound to contribute to secondary brain injury, some more recent data have emerged indicating the potential risks of fluid overload. However, it is acknowledged that many factors govern the relationship between fluid management and cerebral blood flow and oxygenation and more research seems warranted to optimise fluid management and improve outcomes.

Volume therapy in trauma and neurotrauma

Volume therapy in trauma should be directed at the restitution of disordered physiology including volume replacement to re-establishment of tissue perfusion, correction of coagulation deficits and avoidance of fluid overload. Recent literature has emphasised the importance of damage control resuscitation, focussing on the restoration of normal coagulation through increased use of blood products including fresh frozen plasma, platelets and cryoprecipitate. However, once these targets have been met, and in patients not in need of damage control resuscitation, clear fluid volume replacement remains essential. Such volume therapy should include a balance of crystalloids and colloids. Pre-hospital resuscitation should be limited to that required to sustain a palpable radial artery and adequate mentation. Neurotrauma patients require special consideration in both pre-hospital and in-hospital management.

[Cerebral oedema: new therapeutic ways]

Cerebral oedema (CO) after brain injury can occur from different ways. The vasogenic and cytotoxic oedema are usually described but osmotic and hydrostatic CO, respectively secondary to plasmatic hypotonia or increase in blood pressure, can also be encountered. Addition of these several mechanisms can worsen injuries. Consequences are major, leading quickly to death secondary to intracerebral hypertension and later to neuropsychic sequelae. So therapeutic care to control this phenomenon is essential and osmotherapy is actually the only way. A better understanding of physiopathological disorders, particularly energetic ways (lactate), aquaporine function, inflammation lead to new therapeutic hopes. The promising experimental results need now to be confirmed by clinical data.

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.

Place of the colloids in fluid resuscitation of the traumatized patient

PURPOSE OF REVIEW

The examination of the recent literature aimed at analysing the most recent data that could affect decisions regarding the use of colloids in trauma resuscitation.

RECENT FINDINGS

Animal data have generally shown a beneficial effect of colloids in trauma resuscitation, with improvements in capillary leak demonstrated in lung, intestine and brain. In most studies, hydroxyethyl starch resuscitation was more effective than crystalloid and decreased markers of inflammatory processes were observed. Brain injury in animals was attenuated with colloids. In uncontrolled haemorrhage, resuscitation with colloid increased bleeding and mortality.Human studies have also failed to confirm the suggestion that albumin resuscitation may be associated with a worse outcome in head injury. However, there is a strong suggestion that aggressive prehospital resuscitation, particularly with colloid, may be harmful. Studies in burns have consistently shown an improvement in the tendency to fluid overload with the inclusion of colloid in the resuscitation strategy, but so far no outcome benefit has been shown.Two studies of general trauma resuscitation have shown apparent benefit from the use of HES in early resuscitation with reductions in mortality and in renal injury.

SUMMARY

Recent trauma studies provide ongoing, but not conclusive, evidence of a benefit from colloid resuscitation in trauma.

Antioxidant strategies in neurocritical care

An increase in oxidative stress and overproduction of oxidizing reactive species plays an important role in the pathophysiology of several conditions encountered in the neurocritical care setting including: ischemic and hemorrhagic strokes, traumatic brain injury, acute respiratory distress syndrome, sepsis, and organ failure. The presence of oxidative stress in these conditions is supported by a large body of pre-clinical and clinical studies, and provides a rationale to support a potential therapeutic role for antioxidants. The purpose of this article is to briefly review the basic mechanisms and molecular biology of oxidative stress, summarize its role in critically ill neurological patients, and review available data regarding the potential role of antioxidant strategies in neurocritical care and future directions.

From whole blood to component therapy: the economic, supply/demand need for implementation of component therapy in sub-Saharan Africa

Blood may be transfused as whole blood or as one of its components. Because patients seldom require all of the components of whole blood, it makes sense to transfuse only that portion needed by the patient for a specific condition or disease. This treatment, known as "blood component therapy", allows several patients to benefit from one unit of donated whole blood. Blood components include red blood cells, plasma, platelets, and cryoprecipitate. A considerable literature has accumulated over the past decade indicating that leukocytes present in allogeneic cellular blood components, intended for transfusion, are associated with adverse effects to the recipient. These include the development of febrile transfusion reactions, graft-versus-host disease, alloimmunization to leukocyte antigens, and the immunomodulatory effects that might influence the prognosis of patients with a malignancy. Moreover, it has become evident that such leukocytes may be the vector of infectious agents such as cytomegalovirus (CMV), Human T-Lymphotrophic Virus 1/11 (HTLV-I/II), and Epstein Barr (EBV) as well as other viruses. Effective stewardship of blood ensuring that several patients potentially benefit from components derived from one unit of donated whole blood is important for economic, supply/demand reasons and to protect the national inventory at times of national blood shortage. Blood safety in developing countries can be improved by more appropriate use of blood components rather than whole blood transfusion and the provision of alternatives such as oral and intravenous iron, erythropoietin, saline and colloids. This will facilitate the optimal use of the limited blood supply. Political will and open-mindedness to innovative ways to improve supply, appropriateness, optimal use and safety of blood from all types of donors are essential to promote more evidence-based approaches to blood transfusion practice in sub-Saharan Africa.

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.

Acute kidney injury in patients with severe traumatic brain injury: implementation of the acute kidney injury network stage system

BACKGROUND

There is limited information on the incidence and effect of acute kidney injury (AKI) in patients with severe traumatic brain injury (TBI), although AKI may affect outcome. Recently, acute kidney injury network (AKIN) classification has been widely accepted as a consensus definition for AKI. The aim of this study is to estimate the frequency and level of severity of AKI in patients with severe TBI by using AKIN criteria and to study whether AKI affects outcome.

METHODS

The authors retrospectively identified a total of 136 patients with severe TBI admitted to the neurosurgical center during a 3-year period ending May 2010. Demographic data, severity of TBI, serum creatinine, urine output, outcome at 6 month, and death were collected. Renal function was assessed by using AKIN criteria.

RESULTS

Thirty-one patients (23%) were classified as having AKI by using AKIN criteria during their hospitalization. Of them, 21 patients (68%) were stratified as stage 1, 7 patients (22%) as stage 2, and 3 patients (10%) as stage 3. Patients who developed AKI were older, had lower Glasgow coma scale at admission, and had higher level of admission serum creatinine and blood urea nitrogen. Patients with AKI had higher mortality and worse outcome when compared with patients with normal renal function. Furthermore, patients with mild renal dysfunction (stage 1 AKI) are also found having increased mortality and worse long-term outcome, compared with patients without renal dysfunction.

CONCLUSION

It is demonstrated using the newly defined AKIN criteria for renal dysfunction that AKI is a relatively common feature in patients with severe TBI, and even seemingly insignificant decrease in renal function may be associated with worse outcome. This study highlights the importance of close surveillance of renal function and stresses the value of renal hygiene in the severe TBI population.

The incidence of acute kidney injury in patients with traumatic brain injury

There is limited information on the incidence of acute kidney injury (AKI) in patients with traumatic brain injury (TBI) although AKI may contribute to morbidity and mortality. We investigated the incidence of AKI in patients with moderate and severe TBI and the association of AKI with risk factors and outcomes in these patients. We studied all TBI patients over 16 years of age admitted to the two designated trauma hospitals in the state of Victoria, Australia from 1 January to 31 December 2008. Patients were included if they had head trauma and presented with a Glasgow coma scale (GCS) <13. Prospectively collected data from the hospital trauma registries, ICUs, and pathology databases were analyzed retrospectively. Risk injury failure loss end (RIFLE) criteria were used to categorize renal function. The incidence of AKI was 9.2% (19/207). Patients who developed AKI were older, had higher severity of illness scores, and a lower GCS. Overall 42.1% of these patients died in hospital compared with 18.1% in patients without AKI. In univariable linear regression analysis, age, severity of illness, and admitting hospital were associated with AKI. After multivariable logistic regression, the occurrence of AKI was associated with age (p < 0.001) and higher APACHE III scores (p = 0.016). AKI is relatively common even in patients with TBI. Its association with age and APACHE III scores helps identify patients at higher risk of AKI.

Albumin activates astrocytes and microglia through mitogen-activated protein kinase pathways

Following acute brain injury, albumin may gain access to the brain parenchyma. Clinical studies indicate a protective role for albumin in stroke but an increase in mortality associated with albumin administration following traumatic brain injury. We investigated the effects of albumin on astrocyte and microglial activation, and the role of mitogen-activated protein kinases (MAPK) in these responses. Albumin activated ERK1/2, p38 MAPK and JNK signaling pathways in astrocytes, and induced the production of interleukin (IL)-1beta, inducible nitric oxide (NO) synthase, the NO metabolite nitrite, and the chemokine CX3CL1 while reducing the level of S100B. The release of inflammatory markers by astrocytes was partially dependent on p38 MAPK and ERK1/2 pathways, but not JNK. In microglia, albumin exposure activated all three MAPK pathways and produced an increase in IL-1beta and nitrite. Inhibition of p38 MAPK in microglia leads to an increased level of IL1beta, while inhibition of all three MAPKs suppressed the release of nitrite. These results suggest that albumin activates astrocytes and microglia, inducing inflammatory responses involved both in the mechanisms of cellular injury and repair via activation of MAPK pathways, and thereby implicate glial activation in the clinical responses to administration of albumin.