Review Article

Hyponatremia: Exploring Etiological Insights, Diagnostic Challenges, and Evolving Management Paradigms

Khalil Ahmad1
King’s Mill Hospital Sutton in Ashfield, Sherwood Forest, NHS Foundation Trust UK
Ahmad Sajjad Ashraf2
Trauma Centre, Rashid Hospital, Dubai UAE
Zulfiqar Ali3
VIP Clinic, Dubai Health Authority

✉ Correspondence: Khalil Ahmad Email: khalil.ahmad1@nhs.net

DOI https://doi.org/10.70302/jpsim.v6i1.2502
Volume: 6, Issue 1 Pages: 3–10 Published: 10 Mar 2025
Received: 11 Jan 2025 Revised: 10 Feb 2025 Accepted: 24 Feb 2025 Published Online: 10 Mar 2025

Abstract

Hyponatraemia is a very common electrolyte abnormality seen especially in hospitalized patients. It is associated with increased mortality, morbidity and increased length of hospital stay if not addressed properly. Hyponatremia is defined as serum concentration of sodium as less than 135mmol/L. Hyponatremia results from relative excess of total body water to sodium content. Serum sodium concentration is determined by serum water content. Serum concentration of water increases by water intake (driven by thirst or by habit), and it is reduced due to insensible losses from the body like sweating and by urine dilution. The underlying pathophysiological mechanisms leading to hyponatremia depend upon underlying pathological cause leading to disturbances in serum ADH level and urinary water excretion. Hyponatremia can be further divided between mild (Na=130-135 mmol/L). moderate (Na=125-129 mmol/L) and severe (Na 48 hours) called Chronic Hyponatremia with no symptoms to minimal symptoms. Acute Hyponatremia (sever) can present with severe CNS symptoms, increased morbidity and mortality and increased ICU admissions. The treatment with hypertonic saline (1.8% and 2.7% NaCl) for severe symptomatic hyponatremia needs careful monitoring in ICU/HDU. Tolvaptan may be considered in patients with high ADH activity, regardless of whether they are euvolemic or hypervolemic. In summary, hyponatremia should be managed according to the underlying etiology, the duration and degree of hyponatremia, symptoms severity and patients' volume status.

Keywords
Hyponatremia ADH (Antidiuretic hormone) ICU (intensive care unit) HDU (high dependency unit) Acute and Chronic

How to Cite This Article

Ahmad K, Ashraf AS, Ali Z. Hyponatremia: Exploring Etiological Insights, Diagnostic Challenges, and Evolving Management Paradigms. J Pak Soc Intern Med. 2025;6(1):3–10. doi:10.70302/jpsim.v6i1.2502

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Conflict of Interest

All authors declare no competing interests.

Disclosed in accordance with ICMJE and COPE guidelines.

Funding

No specific funding was received for this research.

Funder information follows the Crossref Funder Registry standard.

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CC BY CC BY 4.0 This article is published under the Creative Commons Attribution 4.0 International License. May be shared and adapted with attribution. © 2025 Journal of Pakistan Society of Internal Medicine.
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