Correlation of Measured and Calculated Serum Osmolality During Hyperosmolar Drugs Infusion in Patients After Craniotomy

Study Overview
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Brief Summary
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Osmotherapy has been used as the medical treatment for brain edema and intracranial hypertension in critically brain injured patients. Measurement of serum osmolality during osmotherapy is of clinical importance to determine clinical efficacy, adjust dosage and avoid side effect. Serum osmolality is often measured in laboratory by cryoscopic technique as the reference method. However, in clinical setting, routine measurement of serum osmolality is not feasible at bedside, either in intensive care unit (ICU) or neurosurgical ward. Therefore, clinicians usually estimate serum osmolality by using equations derived from serum osmoles that can be measured by bedside blood gas analysis or routine laboratory chemical analysis, such as sodium, potassium, urea, and glucose. In present study, mannitol or hypertonic saline will be used in patients after craniotomy, and serum osmolality will be measured before and during drug infusion. Investigators hypothesize that the correlation of measured and calculated serum osmolality is better during infusion of hypertonic saline than mannitol.

Official Title
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Correlation of Measured and Calculated Serum Osmolality During Mannitol or Hypertonic Saline Infusion in Patients After Craniotomy

Conditions
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Brain Edema

Intervention / Treatment
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* Drug: 20% mannitol solution, 125 ml, IV infusion in 15 min
* Drug: 3.1% sodium chloride solution, 125 ml, IV infusion in 15 min


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adult patients after elective craniotomy, requiring hyperosmolar agents for prevention or treatment of brain edema Exclusion Criteria: age younger than 18 yr or older than 65 yr history of diabetes unstable hemodynamic condition presence of renal failure

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Mannitol<br>20% mannitol solution, 125 ml, IV infusion in 15 min | Drug: 20% mannitol solution, 125 ml, IV infusion in 15 min<br> <br> |
| Experimental: Hypertonic saline<br>3.1% sodium chloride solution, 125 ml, IV infusion in 15 min | Drug: 3.1% sodium chloride solution, 125 ml, IV infusion in 15 min<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference between the measured and calculated serum osmolality. |  | Immediately before the infusion of mannitol and hypertonic saline, and 15, 30, 60, 120, 240, and 360 minutes after the administration of the study drugs | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Serum osmolality |  | Immediately before the infusion of mannitol and hypertonic saline, and 15, 30, 60, 120, 240, and 360 minutes after the administration of the study drugs | 
| Concentration of serum sodium |  | Immediately before the infusion of mannitol and hypertonic saline, and 15, 30, 60, 120, 240, and 360 minutes after the administration of the study drugs | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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hyperosmolar drugs, mannitol, hypertonic saline, serum osmolality, correlation