Osmotic demyelination syndrome in Intensive Care Unit

Locked-in syndrome after central pontine myelinolysis, an outstanding outcome of two patients

OBJECTIVE

Central pontine myelinolysis (CPM) is a rare demyelinating disease that affects the pons and which can cause extreme disabilities such as locked-in syndrome (LIS) in the initial phase. The aim of the study was to describe the evolution over a 12-month period of two patients with CPM causing an initial LIS.

METHOD

We retrospectively report the unexpected clinical outcome of these two patients in relation with the anatomical damages documented by brain MRI, associated with diffusion tensor imaging and reconstruction of corticospinal tracts in tractography. The following clinical parameters systematically assessed at 3, 6, 9, and 12 months: muscle testing on 12 key muscles (Medical Research Council), prehension metrics (box and block test and purdue pegboard), and independence for acts of daily living (functional independence measure).

RESULTS

Both patients showed a progressive recovery beginning between 2 and 3 months after the onset of symptoms, leading to almost complete autonomy at 12 months (FIM > 110), with motor strength greater than 4/5 in all joint segments (MRC > 50/60). On brain MRI with tractography, CST appeared partially preserved at pons level.

INTERPRETATION

The possibility of a near-complete functional recovery at 12 months is important to consider given the ethical issues at stake and the discussions about limiting care that may take place initially. It seems to be the consequence of reversible myelin damage combined with partially preserved neurons. Development of collateral pathways or resolution of conduction block may explain this recovery. MRI comprising DTI and tractography could play a key role in the prognosis of motor recovery.

Volume replacement in the resuscitation of trauma patients with acute hemorrhage: an umbrella review

BACKGROUND

The use of intravenous fluid therapy in patients with major trauma in prehospital settings is still controversial. We conducted an umbrella review to evaluate which is the best volume expansion in the resuscitation of a hemorrhagic shock to support the development of major trauma guideline recommendations.

METHODS

We searched PubMed, Embase, and CENTRAL up to September 2022 for systematic reviews (SRs) investigating the use of volume expansion fluid on mortality and/or survival. Quality assessment was performed using AMSTAR 2 and the Certainty of the evidence was assessed with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

We included 14 SRs investigating the effects on mortality with the comparisons: use of crystalloids, blood components, and whole blood. Most SRs were judged as critically low with slight overlapping of primary studies and high consistency of results. For crystalloids, inconsistent evidence of effectiveness in 28- to 30-day survival (primary endpoint) was found for the hypertonic saline/dextran group compared with isotonic fluid solutions with moderate certainty of evidence. Pre-hospital blood component infusion seems to reduce mortality, however, as the certainty of evidence ranges from very low to moderate, we are unable to provide evidence to support or reject its use. The blood component ratio was in favor of higher ratios among all comparisons considered with moderate to very low certainty of evidence. Results about the effects of whole blood are very uncertain due to limited and heterogeneous interventions in studies included in SRs.

CONCLUSION

Hypertonic crystalloid use did not result in superior 28- to 30-day survival. Increasing evidence supports the scientific rationale for early use of high-ratio blood components, but their use requires careful consideration. Preliminary evidence is very uncertain about the effects of whole blood and further high-quality studies are required.

Challenge in hyponatremic patients - the potential of a laboratory-based decision support system for hyponatremia to improve patient's safety

OBJECTIVES

Hyponatremia is the most frequent electrolyte disorder in hospitalized patients with increased mortality and morbidity. In this study, we evaluated the follow-up diagnostic, the risk of inadequate fast correction and the outcome of patients with profound hyponatremia (pHN), defined as a blood sodium concentration below 120 mmol/L. The aim was to identify a promising approach for a laboratory-based clinical decision support system (CDSS).

METHODS

This retrospective study included 378,980 blood sodium measurements of 83,315 cases at a German tertiary care hospital. Hospitalized cases with pHN (n=211) were categorized into two groups by the time needed for a follow-up measurement to be performed (time to control, TTC) as either <12 h (group 1: "TTC≤12 h", n=118 cases) or >12 h (group 2: "TTC>12 h", n=93 cases). Length of hospital stay, sodium level at discharge, ward transfers, correction of hyponatremia, and risk of osmotic demyelination syndrome (ODS) due to inadequate fast correction were evaluated with regard to the TTC of sodium blood concentration.

RESULTS

pHN was detected in 1,050 measurements (0.3%) in 211 cases. Cases, in which follow-up diagnostics took longer (TTC>12 h), achieved a significantly lower sodium correction during their hospitalization (11.2 vs. 16.7 mmol/L, p<0.001), were discharged more frequently in hyponatremic states (<135 mmol/L; 58 (62.4%) vs. 43 (36.4%), p<0.001) and at lower sodium blood levels (131.2 vs. 135.0 mmol/L, p<0.001). Furthermore, for these patients there was a trend toward an increased length of hospital stay (13.1 vs. 8.5 days, p=0.089), as well as an increased risk of inadequate fast correction (p<0.001).

CONCLUSIONS

Our study shows that less frequent follow-up sodium measurements in pHN are associated with worse outcomes. Patients with a prolonged TTC are at risk of insufficient correction of hyponatremia, reduced sodium values at discharge, and possible overcorrection. Our results suggest that a CDSS that alerts treating physicians when a control time of >12 h is exceeded could improve patient care in the long term. We are initiating a prospective study to investigate the benefits of our self-invented CDSS (www.ampel.care) for patients with pHN.

Central Pontine Myelinolysis: A Case Report

Central pontine myelinolysis (CPM) classically occurs due to rapid rise in serum osmolarity. Most cases have been associated with a history of chronic alcohol abuse, malnutrition, diuretic abuse, and hyponatremia. The pathological process of CPM starts in the central pons near median raphe and spreads out “like a brush Fire” into the surrounding basis pontis. Extrapontine sites such as internal capsule, basal ganglia, cerebellum, and cerebrum can also be affected. We report a case of 60-year-old male with history of chronic alcoholism who presented to us with severe neurological deficits 10 days after his episode of severe hyponatremia.

Refractory Hypernatremia and Osmotic Demyelination Syndrome After Liver Transplantation: A Case Report

Osmotic demyelination syndrome is an uncommon neurologic condition, characterized by noninflammatory demyelination involving the pons and other areas of the central nervous system. As chronic hyponatremia is frequently associated with cirrhosis, patients undergoing liver transplantation are at an increased risk for developing this condition. We report the case of a patient who developed refractory hypernatremia and osmotic demyelination syndrome after liver transplantation. The patient was a 40-year-old man, who underwent liver transplantation for the treatment of cryptogenic cirrhosis, and had a preoperative sodium level of 128 mmol/L. Although there were no intraoperative complications, the patient showed signs of mental confusion and drowsiness in the second postoperative day, and we noticed an increase to 136 mmol/L in his serum sodium. Treatment with 5% dextrose and desmopressin was initiated, but his serum sodium continued to increase steadily, while his neurologic condition gradually worsened. Serum sodium rose to 157 mmol/L, and a magnetic resonance imaging of the brain showed extensive lesions consistent with osmotic demyelination syndrome. The clinical condition of the patient continued to deteriorate until his death 17 days after the transplant. Although the occurrence of this syndrome after liver transplantation is well described, the steady increase in serum sodium despite early treatment, as described in this case, is highly unusual, and highlights the great attention that must be taken with monitoring and control of serum sodium in patients who undergo liver transplant in the context of chronic hyponatremia. This manuscript is compliant with the Helsinki Congress and the Istanbul Declaration.

The cascade to a serendipitous discovery of lithium-induced nephrogenic diabetes insipidus

Lithium therapy is a common treatment for affective disorders and is widely regarded as a lifesaving drug. However, because its elimination is almost wholly unchanged via the kidneys, both acute and long-term adverse effects relating to toxicity may occur, including declining renal function and nephrogenic diabetes insipidus (DI). DI may be difficult to detect and is frequently preceded by dehydration and which, in our patient, was discovered by chance. We describe a case of an elderly woman on chronic lithium therapy for bipolar affective disorder who initially presented with dehydration from vomiting but possibly developed extra-pontine myelinolysis (EPM) after over-zealous correction of hyponatraemia. Steroids administered appeared to have prevented further progression but a persisting hyperosmolar state then alerted us to the presence of nephrogenic DI. Although both conditions were later successfully reversed with no obvious chronic sequelae, the recovery of the patient was protracted. Clinicians should be vigilant for complications of managing dehydration states in people prescribed with lithium.

The Spectrum of Movement Disorders in Cases with Osmotic Demyelination Syndrome

Background

Osmotic demyelination syndrome (ODS) can be a central pontine myelinolysis (CPM) and extrapontine myelinolysis (EPM) based on the regions involved even though they share the same disease process, aetiopathogenesis and time course.

Objectives

Present study aims to characterize the clinical, radiological features and the outcome of patients with ODS with movement disorders as the forthcoming manifestation.

Methods

Chart review of patients with ODS with movement disorders. Demographic, clinical and radiological details of the patients were reviewed.

Results

Eleven patients (six females; mean age: 48.3 ± 17.6 years) were included in the study. Parkinsonism alone and parkinsonism with dystonia was noted in four patients each (36.4%) while dystonia alone was noted in the other 3 (27.3%). Five patients (45.5%) had postural tremors. While 5 patients had dystonia early in the course of illness (3-7 days), it was delayed (6-9 months) in the other 2. A triphasic course was noted in two patients. The first phase of hyponatremia induced neurological impairment was followed by a second phase of worsening due to the immediate effect of ODS and a third delayed phase of worsening due to delayed effect of ODS. MRI showed both EPM and CPM in eight patients, EPM alone in two patients and CPM alone in 1 patient. Nine patients had a good outcome with mRS < 3.

Conclusion

Parkinsonism and dystonia are important manifestations of ODS. Triphasic course with a delayed phase of worsening of movement disorders is probably due to the maladaptive neuronal repair. The concept of triphasic ODS is first being described in our series.

Osmotic demyelination syndrome improving after immune-modulating treatment: Case report and literature review

BACKGROUND

Osmotic demyelination syndrome (ODS), which embraces central pontine and extrapontine myelinolysis, is an uncommon neurological disorder that occurs due to plasma osmotic changes.

CASE PRESENTATION

We present the case of a 55-year-old man, who presented with severe hyponatremia due to repeated vomiting, antidepressant treatment and consumption of large amounts of water. Fifteen days after sodium correction, the patient showed fluctuation of vigilance, dysarthria and dysphagia, tremor, cogwheel rigidity, bilateral facial palsy, ophthalmoplegia and tetraparesis. A brain MRI scan revealed extrapontine and later on pontine myelinolysis. He received intravenous steroids and subsequently immunoglobulin. His status began to improve gradually after completion of immunoglobulin and at three month-follow-up had no neurological deficit.

LITERATURE REVIEW

A comprehensive literature search of all reported ODS cases that received immunoglobulin, steroids or plasmapheresis was conducted in the electronic databases PubMed and Web of science.

CONCLUSIONS

Improvement was seen in most cases that received immunoglobulin either during treatment or in the first days after treatment. With regard to steroids, although most cases reported improvement in the following months their effect on the outcome is unclear. Most cases treated with plasmapheresis reported favorable outcome at variable follow-up time. Immunoglobulin and steroids have immunomodulatory effects, which could contribute to promotion of myelin repair in ODS. Plasmapheresis has effects on the immune system beyond removing myelinotoxins from the circulation. More evidence is required to support their use in ODS. However, in view of the disease severity, these therapeutic choices should be considered in the clinical management of ODS.

Pontine Myelinolysis Caused by Hypovolemic Hypernatremia

Introduction. Central pontine myelinolysis is characterized by the occurrence of acute demyelinating lesions of cells in the pons secondary to abrupt oscillations of serum osmolarity. Its exact incidence is not well defined, but studies show a prevalence of 0.25 to 0.5% in the general population, 2.5% in the intensive care unit, and up to 10% in patients with risk factors, such as chronic liver disease and hepatic transplantation, alcoholism, malnutrition, diuretic therapy, electrolyte imbalance, hypoglycemia, and hyperglycemia. Case Report. A 70-year-old white female with extranodal diffuse large B-cell non-Hodgkin's lymphoma (extensive mass on the left anterior chest wall), stage IVA, developed pontine myelinolysis secondary to hypovolemic acute hypernatremia, which occurred due to diarrhea caused by chemotherapy (rituximab, cyclophosphamide, doxorubicin, and vincristine). Discussion. Pontine myelinolysis occurs most often due to the rapid correction of chronic hyponatremia. But here, we describe a case of the disease secondary to the occurrence of hypovolemic acute hypernatremia in a patient with a hematological malignancy under treatment, who was on chronic treatment with thiazide diuretics and who presented with other electrolyte disturbances as risk factors for the development of pontine myelinolysis.

Central Pontine Myelinosis and Osmotic Demyelination Syndrome

BACKGROUND

Osmotic demyelination syndrome (ODS), which embraces central pontine myelinolysis (CPM) and extrapontine myelinosis (EPM), is often underdiagnosed in clinical practice, but can be fatal. In this article, we review the etiology, patho- physiology, clinical features, diagnosis, treatment, and prognosis of ODS.

METHODS

Pertinent publications from the years 1959 to 2018 were retrieved by a selective search in PubMed.

RESULTS

The most common cause of ODS is hyponatremia; particular groups of patients, e.g., liver transplant recipients, are also at risk of developing ODS. The pathophysiology of ODS consists of cerebral apoptosis and loss of myelin due to osmotic stress. Accordingly, brain areas that are rich in oligodendrocytes and myelin tend to be the most frequently affected. Patients with ODS often have a biphasic course, the first phase reflecting the underlying predisposing illness and the second phase reflecting ODS itself, with pontine dysfunction, impaired vigilance, and movement disorders, among other neurological abnormalities. The diagnostic modality of choice is magnetic resonance imaging (MRI) of the brain, which can also be used to detect oligosymptomatic ODS. The current mainstay of management is prevention; treatment strategies for manifest ODS are still experimental. The prognosis has improved as a result of MRI-based diagnosis, but ODS can still be fatal (33% to 55% of patients either die or remain permanently dependent on nursing care).

CONCLUSION

ODS is a secondary neurological illness resulting from a foregoing primary disease. Though rare overall, it occurs with greater frequency in certain groups of patients. Clinicians of all specialties should therefore be familiar with the risk constellations, clinical presentation, and prevention of ODS. The treatment of ODS is still experimental at present, as no evidence-based treatment is yet available.

Recognition and Management of Pediatric Salt Toxicity

OBJECTIVES

Immediate recognition of salt toxicity and aggressive resuscitative measures are critical in the treatment of this lethal poisoning. Despite heroic measures, pediatric deaths due to salt toxicity still occur from irreversible neurological damage. The objective of this article is to review the relevant literature and offer a therapeutic algorithm for the management of pediatric patients presenting with salt toxicity.

METHODS

A literature search for cases of salt toxicity was conducted. Articles in English that were available electronically through PubMed and Google Scholar were reviewed.

RESULTS

Nineteen cases and case series of salt toxicity were located using our search strategy. Salt poisoning has a distinct pathophysiology compared with hypernatremia, most notable for the lack of formation of idiogenic osmoles.

CONCLUSIONS

The approach to treatment differs between salt toxicity and hypernatremia, focusing on rapid correction of serum osmolality rather than gradual normalization of serum sodium concentrations. Consultation of nephrology and child protection services are strongly recommended in the comprehensive treatment approach.