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Updated: Jun 24, 2026
05:01
A Detailed Protocol for Physiological Parameters Acquisition and Analysis in Neurosurgical Critical Patients
Published on: October 17, 2017
[Intracranial pressure and hypotonic infusion solutions]
1Physioklin, Luisenstr. 17, 55124, Mainz, Deutschland. zander@physioklin.de
Der Anaesthesist
|March 28, 2009
Summary
Infusing hypotonic fluids can dangerously increase intracranial pressure (ICP), especially in patients with brain injuries. Maintaining isotonic fluids is crucial for patient safety and managing neurological conditions.
Area of Science:
- Physiology
- Neurosurgery
- Intensive Care Medicine
Context:
- Plasma osmolality is a critical physiological parameter, normally 288+/-5 mOsmol/kgH2O.
- In vitro measurements may not reflect in vivo effects, as seen with 5% dextrose solution (D5W).
- Intracranial pressure (ICP) is highly sensitive to changes in plasma osmolality.
Purpose:
- To highlight the importance of fluid osmolality in clinical practice.
- To emphasize the risks associated with administering hypotonic infusion solutions.
- To provide guidance on appropriate fluid selection for patients, particularly those at risk of increased ICP.
Summary:
- Physiological plasma osmolality is approximately 288 mOsmol/kgH2O.
- Hypotonic solutions, like Ringer's lactate (256 mOsmol/kgH2O), shift water intracellularly.
- A mere 3% decrease in plasma osmolality can elevate ICP by 15 mmHg, underscoring the danger of hypotonic infusions.
Impact:
- Avoidance of hypotonic fluid infusions is critical to prevent dangerous elevations in intracranial pressure (ICP).
- Understanding the in vivo effects of infusion fluids is paramount for patient management, especially in neurocritical care.
- Maintaining isotonicity (290+/-10 mOsmol/kgH2O) of infusion fluids is essential for neurological stability and patient safety.
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