What is the milliliter per hour (mL/h) rate of 0.45% sodium chloride (NaCl) solution?

From the Guidelines

The flow rate of 0.45% sodium chloride (NaCl) solution should be 4-14 ml/kg/h, which translates to approximately 250-875 ml/h for a 70 kg adult patient, depending on their hydration status, serum electrolyte levels, and urinary output, as indicated by the most recent and highest quality study 1. To determine the appropriate flow rate, we need to consider the patient's weight, clinical condition, and desired total volume over time.

• The patient's weight is crucial in calculating the flow rate, as the recommended rate is 4-14 ml/kg/h.
• The clinical condition, such as the presence of hypernatremia or dehydration, also plays a significant role in determining the flow rate.
• The desired total volume over time should be calculated based on the patient's estimated fluid deficit and the need to correct it within the first 24 hours. The rate must be adjusted according to the patient's hydration status, electrolyte levels, and medical conditions.
• Half-normal saline contains 77 mEq/L of sodium and chloride, making it hypotonic compared to blood plasma.
• This solution is often used when patients need free water replacement along with some sodium, such as in hypernatremia or in certain cases of dehydration. Before administering any IV fluids, a healthcare provider should assess the patient and determine the appropriate rate based on their specific needs, as recommended by 1 and 1.
• The healthcare provider should monitor the patient's hemodynamic status, fluid input/output, and clinical examination to adjust the flow rate as needed.
• The induced change in serum osmolality should not exceed 3 mOsm kg–1 H2O h–1 to avoid iatrogenic fluid overload, as indicated by 1.

From the Research

Intravenous Fluid Administration

• The ideal intravenous fluid for volume resuscitation is controversially debated, and clinical practice guidelines are scarce 2.
• Normal saline (NS) is most commonly administered, but it has been associated with complications such as hyperchloremic acidosis, dysnatremia, neurologic damage, and fatality 2.
• The mean fluid volumes ranged from 7.9 to 19.1 mL/kg in a study on intravenous fluid administration in acutely ill and injured children 2.

Fluid Status Assessment

• Techniques for assessing fluid status in patients with kidney disease include biomarkers, ultrasound, blood volume monitoring, and bioimpedance 3.
• Biomarkers such as atrial natriuretic peptide and B-type natriuretic peptide provide information about relative changes in fluid status 3.
• Bioimpedance methods and relative blood volume monitoring are increasingly used to assess fluid status in patients with acute or chronic kidney disease 3.

Normal Saline Administration

• The administration of normal saline in critically ill patients may have adverse renal effects 4.
• A study on women with preeclampsia found no differences in serum chloride or creatinine between those who received intravenous normal saline and those who did not 4.
• Renal function indices were preserved despite the introduction of normal saline into routine practice 4.

Intravenous Fluid Therapy in Kidney Disease

• Intravenous fluid therapy is critical in the treatment of kidney disease, including acute kidney injury and uremic crisis associated with chronic kidney disease 5.
• Careful management of fluid dose is necessary to achieve optimal hydration status and avoid further damage or decrease in function from dehydration or overhydration 5.

Relevance to 0.45% Cl Na

• There is no direct information on the administration of 0.45% Cl Na in the provided studies.
• However, the studies provide information on the administration of normal saline and other intravenous fluids in various clinical settings 2, 3, 4, 5.