#dexmedetomidine-calc-container h2 {
color: #2c3e50;
text-align: center;
border-bottom: 2px solid #3498db;
padding-bottom: 10px;
margin-bottom: 20px;
}
.dex-form-group {
margin-bottom: 15px;
background: #f9fbfd;
padding: 15px;
border-radius: 6px;
border: 1px solid #e1e8ed;
}
.dex-form-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
color: #34495e;
}
.dex-form-group input, .dex-form-group select {
width: 100%;
padding: 10px;
border: 1px solid #bdc3c7;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.dex-form-group input:focus {
border-color: #3498db;
outline: none;
box-shadow: 0 0 5px rgba(52, 152, 219, 0.3);
}
.dex-row {
display: flex;
gap: 15px;
flex-wrap: wrap;
}
.dex-col {
flex: 1;
min-width: 200px;
}
button.dex-btn {
background-color: #3498db;
color: white;
border: none;
padding: 12px 20px;
font-size: 18px;
border-radius: 4px;
cursor: pointer;
width: 100%;
font-weight: bold;
transition: background 0.3s;
margin-top: 10px;
}
button.dex-btn:hover {
background-color: #2980b9;
}
#dex-result {
margin-top: 25px;
display: none;
background-color: #e8f6f3;
border: 1px solid #a3e4d7;
padding: 20px;
border-radius: 6px;
}
.dex-result-item {
display: flex;
justify-content: space-between;
margin-bottom: 10px;
font-size: 16px;
color: #2c3e50;
border-bottom: 1px solid #d1f2eb;
padding-bottom: 5px;
}
.dex-result-item:last-child {
border-bottom: none;
}
.dex-result-value {
font-weight: bold;
color: #16a085;
}
.dex-highlight {
font-size: 24px;
color: #e74c3c;
}
.dex-note {
font-size: 12px;
color: #7f8c8d;
margin-top: 10px;
font-style: italic;
}
.article-content {
margin-top: 40px;
line-height: 1.6;
color: #333;
}
.article-content h3 {
color: #2c3e50;
margin-top: 25px;
}
.article-content ul {
padding-left: 20px;
}
.article-content li {
margin-bottom: 8px;
}
.info-box {
background: #f8f9fa;
border-left: 4px solid #3498db;
padding: 15px;
margin: 15px 0;
}
// Toggle custom concentration input
document.getElementById('drugConc').onchange = function() {
var val = document.getElementById('drugConc').value;
var customInput = document.getElementById('customConc');
if(val === 'custom') {
customInput.style.display = 'block';
} else {
customInput.style.display = 'none';
}
};
function calculateDexInfusion() {
// 1. Get Inputs
var weightInput = parseFloat(document.getElementById('ptWeight').value);
var unit = document.getElementById('weightUnit').value;
var doseInput = parseFloat(document.getElementById('doseRate').value);
var concSelect = document.getElementById('drugConc').value;
var concInput = parseFloat(document.getElementById('customConc').value);
// 2. Validate Inputs
if (isNaN(weightInput) || weightInput <= 0) {
alert("Please enter a valid patient weight.");
return;
}
if (isNaN(doseInput) || doseInput <= 0) {
alert("Please enter a valid dose rate (mcg/kg/hr).");
return;
}
// 3. Determine Concentration
var concentration = 4; // Default
if (concSelect === 'custom') {
if (isNaN(concInput) || concInput <= 0) {
alert("Please enter a valid custom concentration.");
return;
}
concentration = concInput;
} else {
concentration = parseFloat(concSelect);
}
// 4. Convert Weight to KG if necessary
var weightKg = weightInput;
if (unit === 'lbs') {
weightKg = weightInput / 2.20462;
}
// 5. Calculation Logic
// Formula: Rate (mL/hr) = [Weight (kg) * Dose (mcg/kg/hr)] / Concentration (mcg/mL)
var totalDrugPerHour = weightKg * doseInput; // mcg/hr
var infusionRate = totalDrugPerHour / concentration; // mL/hr
// 6. Display Results
document.getElementById('resWeight').innerHTML = weightKg.toFixed(2) + " kg";
document.getElementById('resTotalLoad').innerHTML = totalDrugPerHour.toFixed(2) + " mcg/hr";
document.getElementById('resPumpRate').innerHTML = infusionRate.toFixed(1) + " mL/hr";
document.getElementById('dex-result').style.display = 'block';
}
About Dexmedetomidine Dosing
Dexmedetomidine (commonly marketed as Precedex) is a selective alpha-2 adrenergic agonist used primarily for sedation in the Intensive Care Unit (ICU) and during procedural sedation. Unlike other sedatives, it offers "cooperative sedation," allowing patients to be easily aroused and interactive upon stimulation, with minimal respiratory depression.
Warning: This calculator is a clinical support tool for educational purposes only. Always verify calculations independently and follow your institution's specific protocols regarding titration, loading doses, and maximum limits.
The Infusion Rate Formula
Calculating the IV pump rate for continuous infusion requires three primary variables: the patient's weight in kilograms, the desired dose in micrograms per kilogram per hour, and the concentration of the drug solution.
The mathematical formula used in this calculator is:
Pump Rate (mL/hr) = [Weight (kg) × Dose (mcg/kg/hr)] ÷ Concentration (mcg/mL)
Standard Dosing Guidelines
- Initiation: While a loading dose of 1 mcg/kg over 10 minutes is described in labeling, it is frequently omitted in clinical practice to minimize the risk of hypotension and bradycardia.
- Maintenance: Generally initiated at 0.2 to 0.7 mcg/kg/hr.
- Titration: The rate is adjusted to achieve the desired level of sedation (e.g., RASS score targets). Some clinical protocols allow titration up to 1.5 mcg/kg/hr, though this exceeds FDA labeling.
Common Concentrations
Dexmedetomidine is typically supplied in premixed bags or vials requiring dilution.
- Standard Premix: 4 mcg/mL (200 mcg in 50 mL or 400 mcg in 100 mL).
- Concentrated Premix: 8 mcg/mL (often used for fluid-restricted patients).
Clinical Calculation Example
Consider a patient weighing 75 kg. The physician orders a dexmedetomidine infusion start at 0.5 mcg/kg/hr using a standard 4 mcg/mL concentration.
- Calculate total hourly dose: 75 kg × 0.5 mcg/kg/hr = 37.5 mcg/hr.
- Calculate volume per hour: 37.5 mcg/hr ÷ 4 mcg/mL = 9.375 mL/hr.
- The pump would be set to approximately 9.4 mL/hr.
Adverse Effects & Monitoring
The most common side effects associated with dexmedetomidine infusion are hypotension (low blood pressure) and bradycardia (slow heart rate). Continuous monitoring of vital signs is mandatory during infusion. If significant hemodynamic compromise occurs, the infusion may need to be decreased or stopped, and fluid boluses or vasoactive agents may be required.