# Chloremia Disturbances in Critical Care: A Narrative Review of Pathophysiology, Clinical Impact and Management Strategies

## TL;DR

This review discusses how abnormal chloride levels in critically ill patients affect outcomes and explores strategies for managing these disturbances.

## Contribution

The paper provides a comprehensive narrative review on the clinical impact and management of chloremia disturbances in critical care.

## Key findings

- Both hypochloremia and hyperchloremia are linked to increased mortality and ICU complications.
- Balanced crystalloids may reduce adverse kidney events compared to normal saline.
- Chloride levels around 105 mEq/L show threshold effects in sepsis prognosis.

## Abstract

Chloride, the leading extracellular anion, plays a crucial role in acid-base balance, fluid homeostasis, and neuromuscular function. Despite historical underrecognition, emerging evidence demonstrates significant associations between chloremia disturbances and critical care outcomes. This paper aims to narratively review the pathophysiology, clinical features, and management strategies of chloremia disturbances in critically ill patients. Chloremia disturbances are common in ICU patients, with both hypochloremia (<96 mEq/L) and hyperchloremia (>106 mEq/L) independently associated with increased mortality, prolonged ICU length of stay, and organ dysfunction. In sepsis, chloride levels exhibit a prognostic value, with threshold effects around 105 mEq/L. Hyperchloremia particularly increases acute kidney injury risk, while hypochloremia correlates with prolonged mechanical ventilation. The choice of resuscitation fluids significantly influences clinical outcomes, with balanced crystalloids potentially reducing adverse events if compared to normal saline solutions. Recent large-scale trials demonstrate lower rates of major adverse kidney events with chloride-restrictive strategies. Optimal management requires careful patient monitoring along with acid-base assessment. Treatment approaches must identify underlying causes to avoid complications. Prevention strategies include protocol-based fluid therapy, medication selection consideration, and early intervention in high-risk patients. Emerging technologies, including continuous monitoring systems and machine learning algorithms, offer promising advances for predicting and managing chloride disturbances.