Sonographic Optic Nerve Sheath Diameter as a Guide for Correction of Hyponatremia in the Emergency Department: A Cross-sectional Study

Optic nerve sheath diameters in nontraumatic brain injury: A scoping review and role in the intensive care unit

BACKGROUND

Neuromonitoring in medical intensive care units is challenging as most patients are unfit for invasive intracranial pressure (ICP) modalities or unstable to transport for imaging. Ultrasonography-based optic nerve sheath diameter (ONSD) is an attractive option as it is reliable, repeatable and easily performed at the bedside. It has been sufficiently validated in traumatic brain injury (TBI) to be incorporated into the guidelines. However, currently the data for non-TBI patients is inconsistent for a scientific recommendation to be made.

AIM

To compile the existing evidence for understanding the scope of ONSD in measuring ICP in adult non-traumatic neuro-critical patients.

METHODS

PubMed, Google Scholar and research citation analysis databases were searched for studies in adult patients with non-traumatic causes of raised ICP. Studies from 2010 to 2024 in English languages were included.

RESULTS

We found 37 articles relevant to our search. The cutoff for ONSD in predicting ICP varied from 4.1 to 6.3 mm. Most of the articles used cerebrospinal fluid opening pressure followed by raised ICP on computed tomography/magnetic resonance imaging as the comparator parameter. ONSD was also found to be a reliable outcome measure in cases of acute ischaemic stroke, intracerebral bleeding and intracranial infection. However, ONSD is of doubtful utility in septic metabolic encephalopathy, dysnatremias and aneurysmal subarachnoid haemorrhage.

CONCLUSION

ONSD is a useful tool for the diagnosis of raised ICP in non-traumatic neuro-critically ill patients and may also have a role in the prognostication of a subset of patients.

Short-Term Outcomes of Patients With Hyponatremia Presenting to the Emergency Department: An Observational Study

BACKGROUND

Hyponatremia is the predominant electrolyte imbalance disorder in the emergency department. It can manifest with a diverse array of symptoms, ranging from non-specific and moderate to severe and even life-threatening. There is a scarcity of literature addressing the clinical characteristics and prognosis of patients with hyponatremia presenting to the emergency department in the western part of Rajasthan. The objective of this study was to investigate the impact of hyponatremia on the outcomes of patients presenting to the emergency department.

METHODS

In this prospective, cross-sectional, observational study, 200 patients aged more than 18 years who presented to the emergency department with serum sodium < 135 mEq/l were included. The triage of patients was determined by their primary complaints. The primary outcome was to study the clinical profile of patients with hyponatremia presenting to the emergency department. The secondary outcomes were to examine the etiology, i.e., hypovolemic, euvolemic, or hypervolemic, and the outcome of patients on the 7th day (patient admitted to the ward or intensive care unit) and the 28th day (discharged or death) with hyponatremia presenting to the emergency department. The clinical status of the patients was noted by telephonic follow-up in case they were not admitted for this period.

RESULTS

Out of 200 patients, 66 (33%) had hypovolemic, 96 (48%) had euvolemic, and 38 (19%) had hypervolemic hyponatremia. We observed that seizures (84.2%), confusion (56%), and coma (77.7%) were the most common clinical features of patients with severe hyponatremia in the emergency, which was statistically significant than mild and moderate hyponatremia (p = 0.03, 0.023, and 0.029, respectively). On the 7th day of hospitalization, out of 181 (90.5%) admissions in the ward, 116 (64.08%) had severe hyponatremia, and out of 19 (9.5%) ICU admissions, 13 (68.4%) had severe hyponatremia. Death was seen in five (2.5%) patients, one (20%) in moderate and four (80%) in severe hyponatremia cases.

CONCLUSION

Most cases of hyponatremia in this study were euvolemic. Most patients experienced severe hyponatremia, and seizures, confusion, and coma were the most prevalent symptoms. These disorders must be recognized early to properly diagnose and treat hyponatremia and prevent its morbidity and death.

Optic Nerve Sheath Diameter in Hyponatremia: A Closer Look

How to cite this article: Jose J, Suresh V, Magoon R. Optic Nerve Sheath Diameter in Hyponatremia: A Closer Look. Indian J Crit Care Med 2023;27(6):452.

Optic Nerve Sheath Diameter and Sodium Levels: A Friend of a Friend is Still a Stranger

How to cite this article: Arunachala S. Optic Nerve Sheath Diameter and Sodium Levels: A Friend of a Friend is Still a Stranger. Indian J Crit Care Med 2023;27(4):235-236.