Treatment of Hyponatremia in Patients with Acute Neurological Injury

The Evolution of Neurocritical Care Pharmacy: Historical Perspectives and Future Horizons

This article reviews the history and evolution of the neurocritical care (NCC) pharmacy, a subspecialty of critical care pharmacy that focuses on the care of patients with acute neurological disorders. The origins of NCC pharmacies in the 1960s and 1970s are described, when pharmacists began to participate in patient rounds, clinical pharmacokinetic consults, and translational research with neurosurgeons and neurologists. The article also discusses the current state of NCC pharmacy practice, research, and education, highlighting the role of pharmacists as essential members of the NCC team, the contributions of pharmacists to NCC research and guidelines, and the challenges and opportunities for education and training in this unique subspecialty. Finally, the article envisions the future of NCC pharmacy, emphasizing the need for high expectations, visionary leadership, innovative education models, a robust scientific foundation, and multidisciplinary collaboration to advance NCC pharmacy and improve patient outcomes.

Prevention and Correction of Dysnatremia After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Dysnatremia occurs commonly in patients with aneurysmal subarachnoid hemorrhage (aSAH). The mechanisms for development of sodium dyshomeostasis are complex, including the cerebral salt-wasting syndrome, the syndrome of inappropriate secretion of antidiuretic hormone, diabetes insipidus. Iatrogenic occurrence of altered sodium levels plays a role, as sodium homeostasis is tightly linked to fluid and volume management.

METHODS

Narrative review of the literature.

RESULTS

Many studies have aimed to identify factors predictive of the development of dysnatremia, but data on associations between dysnatremia and demographic and clinical variables are variable. Furthermore, although a clear relationship between serum sodium serum concentrations and outcomes has not been established-poor outcomes have been associated with both hyponatremia and hypernatremia in the immediate period following aSAH and set the basis for seeking interventions to correct dysnatremia. While sodium supplementation and mineralocorticoids are frequently administered to prevent or counter natriuresis and hyponatremia, evidence to date is insufficient to gauge the effect of such treatment on outcomes.

CONCLUSIONS

In this article, we reviewed available data and provide a practical interpretation of these data as a complement to the newly issued guidelines for management of aSAH. Gaps in knowledge and future directions are discussed.

Treatment of hyponatremia in children with acute bacterial meningitis

Purpose

Few studies have evaluated hyponatremia management in children with bacterial meningitis (BM). Thus, we aimed to describe variations in clinical practice, the effectiveness of sodium management, and adverse outcomes in children with BM and hyponatremia.

Methods

This retrospective cross-sectional study conducted at a tertiary institution analyzed participants' demographic, clinical, and sodium-altering treatment data. The sodium trigger for treatment was defined as pretreatment sodium level, with response and overcorrection defined as increments of ≥5 and >10 mmol/L after 24 h, respectively.

Results

This study enrolled 364 children with BM (age: <16 years; 215 boys). Hyponatremia occurred in 62.1% of patients, among whom 25.7% received sodium-altering therapies; 91.4% of those individuals had moderate/severe hyponatremia. Monotherapy was the most common initial hyponatremia treatment. After 24 h of treatment initiation, 82.4% of the patients responded. Logistic regression analyses revealed that ΔNa24 <5 mmol/L [odds ratio (OR) 15.52, 95% CI 1.71–141.06, p = 0.015] and minimum Glasgow Coma Scale (GCS) score ≤ 8 (OR 11.09, 95% CI 1.16–105.73, p = 0.036) predicted dysnatremia at 48 h after treatment initiation. Although rare, persistent moderate/severe hyponatremia or hypernatremia at 48 h after treatment initiation was associated with a high mortality rate (57.1%).

Conclusion

This study found that most cases of hyponatremia responded well to various treatments. It is important to identify and institute appropriate treatment early for moderate or severe hyponatremia or hypernatremia in children with BM. This study was limited by its non-randomized nature.

Increase in chloride from baseline is independently associated with mortality in intracerebral hemorrhage patients admitted to intensive care unit: A retrospective study

Background

Hyperchloremia is associated with increased mortality in critically ill patients. The objective of this study was to investigate the association between increased chloride levels and mortality outcomes in intracerebral hemorrhage (ICH) patients admitted to the intensive care unit (ICU).

Methods

We performed a retrospective study of all patients diagnosed with ICH and included in the Medical Information Mart for Intensive Care (MIMIC-Ⅲ) from 2001 to 2012. Inclusion criteria were the first diagnosis of ICH, ICU length of stay (LOS) over 72 h, and not receiving hypertonic saline treatment. Serum chloride perturbation within 72 h of admission was evaluated as a predictor of outcomes. The increase in chloride from baseline was dichotomized based on an increase in chloride in 72 h (≤5 mmol/L or >5 mmol/L). The primary outcome was 90-day mortality.

Results

A total of 376 patients (54.5% male, median age 70 years, interquartile range:58-79 years) were included. The overall 90-day mortality was 32.2% (n=121), in-hospital mortality was 25.8% (n=97), and Day 2 acute kidney injury (AKI) occurred in 29.0% (n=109) of patients. The prevalence of hyperchloremia on admission, during the first 72 h, and an increase in chloride (>5 mmol/L) were 8.8%, 39.4%, and 42.8%, respectively. After adjusting for confounders, the hazard ratio of increase in chloride (>5 mmol/L) was 1.66 (95% confidence interval:1.05-2.64, P=0.031). An increase in chloride (>5 mmol/L) was associated with a higher odds ratio for 90-day mortality in both the AKI and non-AKI groups.

Conclusions

An increase in chloride from baseline is common in adult patients with ICH admitted to ICU. The increase is significantly associated with elevated mortality. These results support the significance of diligently monitoring chloride levels in these patients.

Acute hyponatremia after aneurysmal subarachnoid hemorrhage: Frequency, treatment, and outcome

We retrospectively examined the course of serum sodium levels in 180 patients with acute aneurysmal subarachnoid hemorrhage (SAH) who had been admitted to the anesthesiologic-neurosurgical intensive care unit of the University Medical Center Regensburg, Germany, between January 2014 and December 2018. Each patient file was analyzed regarding the frequency and intensity of hyponatremic episodes and the administered medication. At admission to the intensive care unit (ICU), 18patients had shown initial hyponatremia (<135 mmol/L) and 4 patients hypernatremia (greater than145 mmol/L). 88(48.9%) of the 158 patients with normal serum sodium levels developed at least one hyponatremic episode during ICU treatment. The number of hyponatremic episodes was similar between patients with higher-grade and lower-grade aneurysmal SAH (P = 0.848). At the end of ICU treatment, outcome did not differ between patients with and without hyponatremia (40/88, 45.5% vs. 38/70, 54.3%, P = 0.270). At 6 months after SAH, however, good outcome (Glasgow outcome scale, GOS 4-5) was more frequently observed in patients with hyponatremia (26/88, 29.5% vs. 32/70, 45.7%, P = 0.036). Medication with sodium chloride, fludrocortisone, or tolvaptan was initiated in 75.4% patients with mild hyponatremia (130-134 mmol/L) and in 92.9% with moderate hyponatremia (125-129 mmol/L). At 6 months after SAH, patients treated with tolvaptan had a lower rate of poor outcome than patients who had not received tolvaptan (1/14, 7.1% vs. 25/74, 33.8%, P = 0.045). In patients with acute aneurysmal SAH and hyponatremic episodes, consequent treatment of hyponatremia prevented impaired outcome. Because administration of tolvaptan rapidly normalized serum sodium levels, this therapy seems to be a promising treatment approach.

The Role of Astrogliosis in Formation of the Syrinx in Spinal Cord Injury

A massive localized trauma to the spinal cord results in complex pathologic events driven by necrosis and vascular damage which in turn leads to hemorrhage and edema. Severe, destructive and very protracted inflammatory response is characterized by infiltration by phagocytic macrophages of a site of injury which is converted into a cavity of injury (COI) surrounded by astroglial reaction mounted by the spinal cord. The tissue response to the spinal cord injury (SCI) has been poorly understood but the final outcome appears to be a mature syrinx filled with the cerebrospinal fluid with related neural tissue loss and permanent neurologic deficits. This paper reviews known pathologic mechanisms involved in the formation of the COI after SCI and discusses the integrative role of reactive astrogliosis in mechanisms involved in the removal of edema after the injury. A large proportion of edema fluid originating from the trauma and then from vasogenic edema related to persistent severe inflammation, may be moved into the COI in an active process involving astrogliosis and specifically over-expressed aquaporins.

The Pathogenesis of Neurotrauma Indicates Targets for Neuroprotective Therapies

The spinal cord injury (SCI) initiates an extraordinarily protracted disease with 3 phases; acute, inflammatory, and resolution that are restricted to the cavity of injury (COI) or arachnoiditis by a unique CNS reaction against the severity of destructive inflammation. While the severity of inflammation involving the white matter is fueled by a potently immunogenic activity of damaged myelin, its sequestration in the COI and its continuity with the cerebrospinal fluid of the subdural space allow anti-inflammatory therapeutics infused subdurally to inhibit phagocytic macrophage infiltration and thus provide neuroprotection. The role of astrogliosis in containing and ultimately in eliminating severe destructive inflammation post-trauma appears obvious but is not yet sufficiently understood to use in therapeutic neuroprotective and neuroregenerative strategies. An apparent antiinflammatory activity of reactive astrocytes is paralleled by their active role in removing excess edema fluid in blood-brain barrier damaged by inflammation. Recently elucidated pathogenesis of neurotrauma, including SCI, traumatic brain injury (TBI), and stroke, calls for the following principal therapeutic steps in its treatment leading to the recovery of neurologic function: (1) inhibition and elimination of destructive inflammation from the COI with accompanying reduction of vasogenic edema, (2) insertion into the COI of a functional bridge supporting the crossing of regenerating axons, (3) enabling regeneration of axons to their original synaptic targets by temporary safe removal of myelin in targeted areas of white matter, (4) in vivo, systematic monitoring of the consecutive therapeutic steps. The focus of this paper is on therapeutic step 1.

Variability in Serum Sodium Concentration and Prognostic Significance in Severe Traumatic Brain Injury: A Multicenter Observational Study

BACKGROUND/OBJECTIVE

Dysnatremia is common in severe traumatic brain injury (TBI) patients and may contribute to mortality. However, serum sodium variability has not been studied in TBI patients. We hypothesized that such variability would be independently associated with mortality.

METHODS

We collected 6-hourly serum sodium levels for the first 7 days of ICU admission from 240 severe TBI patients in 14 neurotrauma ICUs in Europe and Australia. We evaluated the association between daily serum sodium standard deviation (dNa_SD), an index of variability, and 28-day mortality.

RESULTS

Patients were 46 ± 19 years of age with a median initial GCS of 6 [4-8]. Overall hospital mortality was 28%. Hypernatremia and hyponatremia occurred in 64% and 24% of patients, respectively. Over the first 7 days in ICU, serum sodium standard deviation was 2.8 [2.0-3.9] mmol/L. Maximum daily serum sodium standard deviation (dNa_SD) occurred at a median of 2 [1-4] days after admission. There was a significant progressive decrease in dNa_SD over the first 7 days (coefficient - 0.15 95% CI [- 0.18 to - 0.12], p < 0.001). After adjusting for baseline TBI severity, diabetes insipidus, the use of osmotherapy, the occurrence of hypernatremia, and hyponatremia and center, dNa_SD was significantly independently associated with 28-day mortality (HR 1.27 95% CI (1.01-1.61), p = 0.048).

CONCLUSIONS

Our study demonstrates that daily serum sodium variability is an independent predictor of 28-day mortality in severe TBI patients. Further prospective investigations are necessary to confirm the significance of sodium variability in larger cohorts of TBI patients and test whether attenuating such variability confers outcome benefits to such patients.

Hyponatremia in the Neurologically Ill Patient: A Review

Hyponatremia is a well-known disorder commonly faced by clinicians managing neurologically ill patients. Neurological disorders are often associated with hyponatremia during their acute presentation and can be associated with specific neurologic etiologies and symptoms. Patients may present with hyponatremia with traumatic brain injury, develop hyponatremia subacutely following aneurysmal subarachnoid hemorrhage, or may manifest with seizures due to hyponatremia itself. Clinicians caring for the neurologically ill patient should be well versed in identifying these early signs, symptoms, and etiologies of hyponatremia. Early diagnosis and treatment can potentially avoid neurologic and systemic complications in these patients and improve outcomes. This review focuses on the causes and findings of hyponatremia in the neurologically ill patient and discusses the pathophysiology, diagnoses, and treatment strategies for commonly encountered etiologies.

Pharmacotherapy of sodium disorders in neurocritical care

PURPOSE OF REVIEW

To describe the pathophysiology and pharmacotherapy of dysnatremia in neurocritical care patients.

RECENT FINDINGS

Sodium disorders may affect approximately half of the neurocritical care patients and are associated with worse neurological outcome and increased risk of death. Pharmacotherapy of sodium disorders in neurocritical care patients may be challenging and is guided by a careful investigation of water and sodium balance.

SUMMARY

In case of hyponatremia, because of excessive loss of sodium, fluid challenge with isotonic solution, associated with salt intake is the first-line therapy, completed with mineralocorticoids if needed. In case of hyponatremia because of SIADH, fluid restriction is the first-line therapy followed by urea if necessary. Hypernatremia should always be treated with hypotonic solutions according to the free water deficit, associated in case of DI with desmopressin. The correction speed should take into consideration the symptoms associated with dysnatremia and the rapidity of the onset.

Hyponatremia in Children With Bacterial Meningitis

Background: Hyponatremia has frequently been described as a common complication associated with bacterial meningitis, though its frequency and clinical course in children with bacterial meningitis are unclear. The present study aimed to investigate the frequency, clinical characteristics, and prognosis associated with pediatric hyponatremia due to bacterial meningitis. Methods: We performed a retrospective review of children with bacterial meningitis provided with standard care. One hundred seventy-five children were included. We documented all participants' symptoms and signs, laboratory and microbiological data, radiological findings, and complications that occurred during their hospital admission. Disease severity was determined using the maximum Pediatric Cerebral Performance Category (PCPC) and minimum Glasgow Coma Scale (GCS). Residual deficits were assessed using PCPC at discharge. Results: Hyponatremia (<135 mmol/L) was seen in 116 (66.4%) of the patients assessed and was classified as mild (130-135 mmol/L) in 77, moderate (125-129 mmol/L) in 26, and severe (<125 mmol/L) in 13. Hyponatremia was associated with a shorter duration of symptoms before admission, higher CSF white cell counts, and a longer duration of hospitalization. Moderate and severe hyponatremia were associated with an increase in convulsions, impaired consciousness, altered CSF protein levels, higher maximum PCPC scores, and lower minimum GCS scores. Severe hyponatremia was further associated with the development of systemic complications including shock, multiple organ dysfunction syndrome, respiratory failure requiring mechanical ventilation, and an increase in poor outcome (PCPC ≥ 2). Hyponatremia was not associated with the development of neurologic complications. Logistic regression analyses revealed that convulsions (OR 12.09, 95% CI 2.63-56.84) and blood glucose levels > 6.1 mmol/L (OR 8.28, 95% CI 1.65-41.60) predicted severe hyponatremia. Conclusion: Hyponatremia occurred in 66.4% of the assessed pediatric bacterial meningitis patients. Moderate and severe hyponatremia affected the severity of pediatric bacterial meningitis. Only severe hyponatremia affected the short-term prognosis of patients with pediatric bacterial meningitis. We recommend that patients with pediatric bacterial meningitis who exhibit convulsions and increased blood glucose levels should be checked for severe hyponatremia. Further studies are needed to evaluate the effectiveness of treatment of hyponatremia.

Practical document on the management of hyponatremia in critically ill patients

Hyponatremia is the most prevalent electrolyte disorder in Intensive Care Units. It is associated with an increase in morbidity, mortality and hospital stay. The majority of the published studies are observational, retrospective and do not include critical patients; hence it is difficult to draw definitive conclusions. Moreover, the lack of clinical evidence has led to important dissimilarities in the recommendations coming from different scientific societies. Finally, etiopathogenic mechanisms leading to hyponatremia in the critical care patient are complex and often combined, and an intensive analysis is clearly needed. A study was therefore made to review all clinical aspects about hyponatremia management in the critical care setting. The aim was to develop a Spanish nationwide algorithm to standardize hyponatremia diagnosis and treatment in the critical care patient.