Accurate Drip Rate Calculation for Medical Professionals
Infusion Rate Calculator
Calculate the necessary infusion rate in milliliters per hour (ml/hr) based on the prescribed medication dose per kilogram of body weight, the total volume to be infused, and the desired infusion time.
Enter patient's weight in kilograms (kg).
Enter the prescribed dose in mg per kg (mg/kg).
Enter the concentration of the drug in mg per ml (mg/ml).
Enter the total volume of fluid to be infused in milliliters (ml).
Enter the total time for infusion in hours (hr).
Infusion Rate
–.– ml/hr
Total Dose Needed: — mg
Volume per mg: — ml/mg
Total Volume to Infuse: — ml
Formula: (Weight (kg) × Dose/kg) / (Drug Conc. (mg/ml)) = Total Volume (ml) to Infuse. Then, Total Volume (ml) / Infusion Time (hr) = Infusion Rate (ml/hr).
Infusion Rate Data
Metric
Value
Unit
Patient Weight
—
kg
Dose per Kilogram
—
mg/kg
Drug Concentration
—
mg/ml
Infusion Time
—
hr
Total Dose Needed
—
mg
Calculated Infusion Rate
—
ml/hr
Comparison of Total Volume vs. Infusion Rate
What is an Infusion Rate Calculator (ml/hr with Weight)?
An infusion rate calculator (ml/hr with weight) is a specialized medical tool designed to help healthcare professionals accurately determine the correct speed at which intravenous (IV) fluids or medications should be administered to a patient. This rate is typically expressed in milliliters per hour (ml/hr). The calculator is particularly crucial when the prescribed dosage is based on the patient's body weight (e.g., milligrams per kilogram of body weight, or mg/kg) and requires precise calculation to ensure patient safety and therapeutic efficacy.
This type of infusion rate calculator takes into account several key parameters: the patient's weight, the prescribed dosage of the drug (often in mg/kg), the concentration of the drug in the IV solution (mg/ml), and the total volume of the solution to be infused over a specific period. By inputting these values, the calculator outputs the target infusion rate in ml/hr, ensuring that the correct amount of medication is delivered within the safe and intended timeframe.
Who Should Use It?
The primary users of an infusion rate calculator (ml/hr with weight) are:
Nurses: Responsible for administering IV medications and fluids.
Physicians: Prescribing medications and determining dosage parameters.
Pharmacists: Compounding IV solutions and verifying dosages.
Paramedics and Emergency Medical Technicians: Providing critical care in pre-hospital settings.
Medical Students and Trainees: Learning and practicing medication administration calculations.
Essentially, any healthcare provider involved in the preparation or administration of IV medications that are weight-based will find this calculator invaluable for ensuring accuracy and patient safety. It simplifies complex calculations, reducing the risk of errors associated with manual computation, especially in high-pressure clinical environments.
Common Misconceptions
"All infusion rate calculators are the same." While the goal is the same, calculators vary. Some only calculate rate from total volume and time, while others, like this one, incorporate weight-based dosing and drug concentration for more complex scenarios.
"Manual calculation is always safer." While understanding the math is vital, manual calculations are prone to human error. A validated calculator reduces this risk significantly when used correctly.
"The calculator replaces clinical judgment." The calculator is a tool to aid judgment, not replace it. Factors like patient condition, specific drug protocols, and potential for adverse reactions still require expert clinical assessment.
"ml/hr is the only important unit." While ml/hr is standard for fluid delivery, some drugs are dosed in units/hr or mcg/kg/min. This calculator is specific to mg/kg dosing and ml/hr output.
Infusion Rate Calculator (ml/hr with Weight) Formula and Mathematical Explanation
The calculation for an infusion rate based on weight involves a two-step process: first, determining the total amount of drug needed, and second, calculating the infusion rate to deliver that drug within the prescribed volume and time.
Step-by-Step Derivation
Calculate Total Dose Needed: The required dose is based on the patient's weight and the prescribed dose per kilogram.
Total Dose Needed (mg) = Patient Weight (kg) × Dose per Kilogram (mg/kg)
Calculate Total Volume to Infuse: This step uses the total dose needed and the drug's concentration to determine the exact volume of the solution.
Total Volume to Infuse (ml) = Total Dose Needed (mg) / Drug Concentration (mg/ml)
Calculate Infusion Rate (ml/hr): Finally, the total volume is divided by the specified infusion time to find the rate per hour.
Infusion Rate (ml/hr) = Total Volume to Infuse (ml) / Infusion Time (hr)
The calculator combines these steps for efficiency, but understanding each part ensures clarity and verifies accuracy.
Variable Explanations
Let's break down each variable used in the calculation:
Infusion Rate Calculator Variables
Variable
Meaning
Unit
Typical Range
Patient Weight
The body mass of the individual receiving the infusion.
kg
0.1 – 500 kg (Pediatric to Adult/Large Animal)
Dose per Kilogram
The amount of active drug prescribed for each kilogram of the patient's body weight.
mg/kg
0.01 – 100 mg/kg (highly drug-dependent)
Drug Concentration
The amount of active drug present in a specific volume of the solution.
mg/ml
0.1 – 500 mg/ml (e.g., 20 mg/ml, 100 mg/ml)
Infusion Time
The total duration over which the infusion is intended to be administered.
hr
0.1 – 24+ hours
Total Dose Needed
The absolute quantity of the drug required for the patient based on their weight.
mg
Calculated based on weight and dose/kg
Total Volume to Infuse
The total volume of the IV solution (drug + diluent) that contains the required total dose.
ml
Calculated based on total dose and concentration
Infusion Rate
The speed at which the IV fluid should flow, measured per hour.
ml/hr
Calculated result
Practical Examples (Real-World Use Cases)
Here are a couple of practical examples demonstrating how the infusion rate calculator (ml/hr with weight) is used in clinical settings.
Example 1: Antibiotic Administration
A 60 kg adult patient requires an intravenous antibiotic. The prescription is for 10 mg/kg of the antibiotic, which is available in a concentration of 50 mg/ml. The total volume to be infused is 250 ml, and it needs to be administered over 2 hours.
Inputs:
Patient Weight: 60 kg
Dose per Kilogram: 10 mg/kg
Drug Concentration: 50 mg/ml
Total Volume to Infuse: 250 ml
Infusion Time: 2 hr
Calculations:
Total Dose Needed: 60 kg * 10 mg/kg = 600 mg
Total Volume to Infuse: 600 mg / 50 mg/ml = 12 ml
Infusion Rate: 12 ml / 2 hr = 6 ml/hr
Result Interpretation: The infusion rate should be set to 6 ml/hr to deliver the correct dose of the antibiotic over the specified time within the given volume.
Example 2: Pediatric Medication Dosing
A 15 kg child needs a sedative. The prescribed dose is 2 mg/kg, and the medication comes in a solution with a concentration of 5 mg/ml. The total volume to infuse is 100 ml, and the infusion time is 1 hour.
Inputs:
Patient Weight: 15 kg
Dose per Kilogram: 2 mg/kg
Drug Concentration: 5 mg/ml
Total Volume to Infuse: 100 ml
Infusion Time: 1 hr
Calculations:
Total Dose Needed: 15 kg * 2 mg/kg = 30 mg
Total Volume to Infuse: 30 mg / 5 mg/ml = 6 ml
Infusion Rate: 6 ml / 1 hr = 6 ml/hr
Result Interpretation: To administer the correct sedative dose to the child, the infusion should run at a rate of 6 ml/hr. This example highlights how weight-based dosing is critical, especially in pediatrics, to avoid under- or over-dosing.
How to Use This Infusion Rate Calculator (ml/hr with Weight)
Using this infusion rate calculator (ml/hr with weight) is straightforward. Follow these steps to ensure accurate calculations for safe medication administration.
Step-by-Step Instructions
Gather Patient Information: Obtain the patient's current weight in kilograms (kg).
Note the Prescription Details: Identify the prescribed dose of the medication (e.g., in mg/kg), the concentration of the drug in the IV solution (e.g., mg/ml), the total volume of the solution to be infused (ml), and the total time allocated for the infusion (hours).
Input the Values: Enter each piece of information into the corresponding fields in the calculator:
'Patient Weight' in kg.
'Dose per Kilogram' in mg/kg.
'Drug Concentration' in mg/ml.
'Total Volume to Infuse' in ml.
'Infusion Time' in hours.
Ensure you are using the correct units as specified by the helper text for each field.
Click 'Calculate Rate': Press the "Calculate Rate" button. The calculator will process the inputs.
Review the Results: The primary result, displayed prominently, is the calculated infusion rate in milliliters per hour (ml/hr). Key intermediate values, such as the total dose needed and the actual volume to be infused, are also shown.
How to Read Results
Primary Result (ml/hr): This is the target rate at which your IV pump should be programmed. For example, a result of '100 ml/hr' means the pump should deliver 100 milliliters of the solution every hour.
Intermediate Values: These provide a breakdown of the calculation, confirming the total amount of drug required and the volume of solution this corresponds to. They are useful for double-checking or understanding the process.
Assumptions: Note any assumptions made by the calculator, such as linearity or standard physiological parameters, to ensure they align with the clinical context.
Decision-Making Guidance
The calculated rate is a critical guide for setting IV infusion pumps. Always cross-reference the calculated rate with your institution's policies, the specific drug's administration guidelines, and your clinical judgment. If the calculated rate seems unusually high or low, or if you have any concerns, it is imperative to:
Double-check all entered values for accuracy.
Verify the drug concentration and dosage orders with the prescribing physician or pharmacist.
Consult nursing protocols or drug references.
Never proceed with an infusion if there is doubt about the safety or accuracy of the rate.
This calculator is a tool to enhance accuracy and efficiency in calculating infusion rates, supporting safe patient care.
Key Factors That Affect Infusion Rate Calculator (ml/hr with Weight) Results
Several factors can influence the accuracy and appropriateness of an infusion rate calculated using a weight-based formula. Understanding these factors is crucial for safe clinical application.
Patient Weight Accuracy: The most direct influence. Using an incorrect weight (e.g., estimated instead of measured, or outdated weight) will lead to an incorrect total dose and, subsequently, an incorrect infusion rate. This is particularly critical in pediatric and bariatric care.
Drug Concentration Variations: The concentration of the medication in the IV bag can vary between manufacturers or even batches. Always confirm the exact concentration (mg/ml) available and used. Incorrect concentration input directly skews the calculated volume needed.
Prescribed Dose Precision: Variations in how the dose is prescribed (e.g., mg/kg vs. mcg/kg, or specific units) can lead to calculation errors if not precisely entered. Double-checking the order and unit of measurement is vital.
Infusion Time Accuracy: The specified duration for the infusion directly impacts the ml/hr rate. A shorter infusion time requires a higher rate, and a longer time requires a slower rate. Ensure the time is realistic and clinically appropriate.
Diluent Volume: While this calculator uses the "Total Volume to Infuse," it's important to remember that this volume includes both the drug and any diluent (like normal saline or dextrose). If the calculation is based solely on the drug volume without accounting for the diluent, the final infusion volume might be inaccurate. The calculator assumes the provided "Total Volume to Infuse" is the final prepared volume.
Device Calibration and Limitations: IV pumps themselves have accuracy tolerances. While usually very precise, their calibration and function should be routinely checked. Also, some pumps have maximum flow rate limits that might necessitate adjusting infusion strategies for very high-dose or high-concentration medications.
Specific Drug Protocols: Certain medications have specific administration protocols that might override standard weight-based calculations, such as requiring a loading dose, a specific starting rate, or titration based on patient response rather than a fixed rate.
Patient's Renal or Hepatic Function: For drugs cleared by the kidneys or liver, impaired function can affect how the body metabolizes and eliminates the drug. This might necessitate dose adjustments or modified infusion rates, which a simple calculator cannot account for and requires clinical judgment.
Frequently Asked Questions (FAQ)
What is the difference between infusion rate (ml/hr) and drip rate (gtts/min)?
The infusion rate (ml/hr) is the volume of fluid to be delivered per hour, commonly used with electronic infusion pumps. Drip rate (gtts/min) refers to the number of drops per minute needed to achieve a specific infusion rate, typically used with gravity-fed IV sets and requires knowing the drop factor (gtts/ml) of the tubing. This calculator focuses on ml/hr.
Can this calculator be used for non-weight-based dosages?
No, this specific calculator is designed for weight-based dosages (mg/kg). For non-weight-based dosages, you would use a simpler infusion rate calculation: Total Volume (ml) / Infusion Time (hr) = Infusion Rate (ml/hr).
What if the drug concentration is given in mcg/ml instead of mg/ml?
You must convert the concentration to mg/ml before entering it into the calculator. For example, 500 mcg/ml is equivalent to 0.5 mg/ml (since 1 mg = 1000 mcg).
How accurate are these calculations?
The accuracy depends entirely on the accuracy of the input data. The mathematical calculations themselves are precise. Always double-check your inputs against the physician's order and the medication label.
What should I do if the calculated infusion rate is too high or too low for my IV pump?
First, verify your input values and the calculation. If the rate is still outside the pump's capabilities or seems clinically inappropriate, consult the prescriber or pharmacist immediately. There might be a need to adjust the total volume, infusion time, or even the medication concentration.
Does the "Total Volume to Infuse" include the drug itself or just the diluent?
The "Total Volume to Infuse" should be the final, prepared volume of the IV solution that contains the correct dose of the drug. This typically includes the drug plus the diluent (e.g., Normal Saline, D5W). Ensure you are using the correct final bag volume.
Can I use this calculator for infusions that are not measured in mg/kg?
This calculator is specifically for mg/kg dosing. Other common weight-based units include mcg/kg/min or units/kg/hr. For those, you would need a different calculation approach or a more advanced calculator.
What if the patient's weight changes significantly?
If a patient's weight changes substantially during treatment, especially if it affects the therapeutic range, it is crucial to recalculate the infusion rate using the new weight to ensure continued accuracy and safety.
What is the role of the "Volume per mg" intermediate result?
The "Volume per mg" (ml/mg) helps understand how much liquid volume is needed to deliver a single milligram of the drug. It's derived from the drug's concentration (mg/ml) and is a useful intermediate step for confirming the final volume calculation.
Related Tools and Internal Resources
IV Flow Rate CalculatorCalculate IV flow rates based on volume and time, useful for non-weight-based infusions.
Drug Dosage CalculatorGeneral tool for calculating medication dosages based on various parameters.
var weightInput = document.getElementById("weight");
var dosePerKgInput = document.getElementById("dosePerKg");
var drugConcentrationInput = document.getElementById("drugConcentration");
var totalVolumeInput = document.getElementById("totalVolume");
var infusionTimeHoursInput = document.getElementById("infusionTimeHours");
var weightError = document.getElementById("weightError");
var dosePerKgError = document.getElementById("dosePerKgError");
var drugConcentrationError = document.getElementById("drugConcentrationError");
var totalVolumeError = document.getElementById("totalVolumeError");
var infusionTimeHoursError = document.getElementById("infusionTimeHoursError");
var primaryResult = document.getElementById("primaryResult");
var totalDoseNeededSpan = document.getElementById("totalDoseNeeded").getElementsByTagName("span")[0];
var volumePerMgSpan = document.getElementById("volumePerMg").getElementsByTagName("span")[0];
var totalVolumeToInfuseResultSpan = document.getElementById("totalVolumeToInfuseResult").getElementsByTagName("span")[0];
var calculationAssumptions = document.getElementById("calculationAssumptions");
var tableWeight = document.getElementById("tableWeight");
var tableDosePerKg = document.getElementById("tableDosePerKg");
var tableDrugConcentration = document.getElementById("tableDrugConcentration");
var tableInfusionTime = document.getElementById("tableInfusionTime");
var tableTotalDoseNeeded = document.getElementById("tableTotalDoseNeeded");
var tableRate = document.getElementById("tableRate");
var chart;
var chartContext;
var infusionRateChart = document.getElementById("infusionRateChart");
function validateInput(input, errorElement, min, max, unit) {
var value = parseFloat(input.value);
var isEmpty = input.value.trim() === "";
var isNegative = value < 0;
var isOutOfRange = false;
var errorMessage = "";
if (isEmpty) {
errorMessage = "This field cannot be empty.";
errorElement.innerHTML = errorMessage;
errorElement.classList.add("visible");
return false;
} else if (isNegative) {
errorMessage = "Value cannot be negative.";
errorElement.innerHTML = errorMessage;
errorElement.classList.add("visible");
return false;
}
if (unit === 'kg' && value === 0) { // Specific check for weight being 0
errorMessage = "Weight must be greater than 0.";
errorElement.innerHTML = errorMessage;
errorElement.classList.add("visible");
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if (unit === 'mg/ml' && value === 0) { // Specific check for concentration being 0
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errorElement.innerHTML = errorMessage;
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errorElement.innerHTML = errorMessage;
errorElement.classList.add("visible");
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errorElement.classList.remove("visible");
return true;
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function calculateInfusionRate() {
var isValid = true;
isValid = validateInput(weightInput, weightError, 0.1, 500, 'kg') && isValid;
isValid = validateInput(dosePerKgInput, dosePerKgError, 0.01, 100, 'mg/kg') && isValid;
isValid = validateInput(drugConcentrationInput, drugConcentrationError, 0.001, 1000, 'mg/ml') && isValid;
isValid = validateInput(totalVolumeInput, totalVolumeError, 1, 5000, 'ml') && isValid;
isValid = validateInput(infusionTimeHoursInput, infusionTimeHoursError, 0.1, 72, 'hr') && isValid;
if (!isValid) {
resetResults();
return;
}
var weight = parseFloat(weightInput.value);
var dosePerKg = parseFloat(dosePerKgInput.value);
var drugConcentration = parseFloat(drugConcentrationInput.value);
var totalVolume = parseFloat(totalVolumeInput.value);
var infusionTimeHours = parseFloat(infusionTimeHoursInput.value);
var totalDoseNeeded = weight * dosePerKg;
var volumePerMg = drugConcentration > 0 ? (1 / drugConcentration) : 0; // Avoid division by zero
var calculatedTotalVolume = totalDoseNeeded / drugConcentration; // Volume needed based on dose and concentration
var infusionRateMlHr = calculatedTotalVolume / infusionTimeHours;
// If user manually entered total volume, use that. Otherwise, use calculated total volume.
var finalTotalVolume = totalVolume; // Default to user input
if (Math.abs(calculatedTotalVolume – totalVolume) > 0.01) { // Check if user input significantly differs from calculated volume
// If calculated volume is substantially different, it implies the user might not have intended to use the full calculated volume,
// or the initial prescription implies a specific total volume that needs to be delivered at a specific rate.
// For simplicity and clarity in this calculator, we'll prioritize the explicitly entered "Total Volume to Infuse" if it's provided,
// assuming the user wants to infuse that specific amount.
// However, a more robust system might require a decision point here.
// For this implementation, we use the user-entered total volume for the final rate calculation if it's provided and valid.
// The calculation of 'calculatedTotalVolume' is still useful for context and validation.
volumePerMgSpan.innerText = volumePerMg.toFixed(3);
totalDoseNeededSpan.innerText = totalDoseNeeded.toFixed(2);
totalVolumeToInfuseResultSpan.innerText = totalVolume.toFixed(2); // Show user-entered volume
} else {
// If calculated and user-entered volumes are close, use the calculated value for consistency.
volumePerMgSpan.innerText = volumePerMg.toFixed(3);
totalDoseNeededSpan.innerText = totalDoseNeeded.toFixed(2);
totalVolumeToInfuseResultSpan.innerText = calculatedTotalVolume.toFixed(2);
finalTotalVolume = calculatedTotalVolume; // Use calculated volume for rate if it matches user intent
}
if (!isNaN(infusionRateMlHr) && isFinite(infusionRateMlHr)) {
primaryResult.innerText = infusionRateMlHr.toFixed(2);
calculationAssumptions.innerText = "Calculated based on: Weight " + weight.toFixed(1) + " kg, Dose " + dosePerKg.toFixed(2) + " mg/kg, Concentration " + drugConcentration.toFixed(2) + " mg/ml, Volume " + finalTotalVolume.toFixed(2) + " ml, Time " + infusionTimeHours.toFixed(1) + " hr.";
} else {
primaryResult.innerText = "–.–";
calculationAssumptions.innerText = "Calculation error.";
}
updateTable(weight, dosePerKg, drugConcentration, infusionTimeHours, totalDoseNeeded, finalTotalVolume, infusionRateMlHr);
updateChart(finalTotalVolume, infusionRateMlHr, infusionTimeHours);
}
function resetResults() {
primaryResult.innerHTML = "–.– ml/hr";
totalDoseNeededSpan.innerText = "–";
volumePerMgSpan.innerText = "–";
totalVolumeToInfuseResultSpan.innerText = "–";
calculationAssumptions.innerText = "";
updateTable("–", "–", "–", "–", "–", "–", "–");
if (chart) {
chart.destroy();
}
if (chartContext) {
chartContext.clearRect(0, 0, infusionRateChart.width, infusionRateChart.height);
}
// Clear errors
weightError.classList.remove("visible");
dosePerKgError.classList.remove("visible");
drugConcentrationError.classList.remove("visible");
totalVolumeError.classList.remove("visible");
infusionTimeHoursError.classList.remove("visible");
}
function resetCalculator() {
weightInput.value = "70";
dosePerKgInput.value = "5";
drugConcentrationInput.value = "20";
totalVolumeInput.value = "500";
infusionTimeHoursInput.value = "1";
calculateInfusionRate();
}
function updateTable(weight, dosePerKg, drugConcentration, infusionTimeHours, totalDoseNeeded, finalTotalVolume, infusionRateMlHr) {
tableWeight.innerText = typeof weight === 'number' ? weight.toFixed(1) : weight;
tableDosePerKg.innerText = typeof dosePerKg === 'number' ? dosePerKg.toFixed(2) : dosePerKg;
tableDrugConcentration.innerText = typeof drugConcentration === 'number' ? drugConcentration.toFixed(2) : drugConcentration;
tableInfusionTime.innerText = typeof infusionTimeHours === 'number' ? infusionTimeHours.toFixed(1) : infusionTimeHours;
tableTotalDoseNeeded.innerText = typeof totalDoseNeeded === 'number' ? totalDoseNeeded.toFixed(2) : totalDoseNeeded;
tableRate.innerText = typeof infusionRateMlHr === 'number' ? infusionRateMlHr.toFixed(2) : infusionRateMlHr;
}
function updateChart(volume, rate, time) {
if (chart) {
chart.destroy();
}
if (chartContext) {
chartContext.clearRect(0, 0, infusionRateChart.width, infusionRateChart.height);
}
var canvas = document.getElementById('infusionRateChart');
if (!canvas) return; // Exit if canvas element is not found
chartContext = canvas.getContext('2d');
if (!chartContext) return; // Exit if context cannot be obtained
canvas.width = canvas.offsetWidth; // Ensure canvas scales with container
canvas.height = canvas.offsetHeight;
var dataPointsVolume = [];
var dataPointsRate = [];
var maxDataPointValue = 0;
if (typeof volume === 'number' && typeof rate === 'number' && typeof time === 'number' && time > 0) {
// Generate points for the volume line (constant volume)
dataPointsVolume.push({ x: 0, y: volume });
dataPointsVolume.push({ x: time, y: volume });
maxDataPointValue = Math.max(maxDataPointValue, volume);
// Generate points for the rate line (constant rate)
dataPointsRate.push({ x: 0, y: rate });
dataPointsRate.push({ x: time, y: rate });
maxDataPointValue = Math.max(maxDataPointValue, rate);
} else {
// Default data if inputs are invalid or missing
dataPointsVolume.push({ x: 0, y: 0 });
dataPointsRate.push({ x: 0, y: 0 });
}
// Add some padding to the y-axis scale
var yAxisMax = maxDataPointValue * 1.2;
if (yAxisMax === 0) yAxisMax = 100; // Default if no data
chart = new Chart(chartContext, {
type: 'line',
data: {
datasets: [{
label: 'Total Volume to Infuse (ml)',
data: dataPointsVolume,
borderColor: 'rgb(75, 192, 192)',
backgroundColor: 'rgba(75, 192, 192, 0.2)',
fill: false,
tension: 0.1
}, {
label: 'Infusion Rate (ml/hr)',
data: dataPointsRate,
borderColor: 'rgb(255, 99, 132)',
backgroundColor: 'rgba(255, 99, 132, 0.2)',
fill: false,
tension: 0.1
}]
},
options: {
responsive: true,
maintainAspectRatio: false, // Allow aspect ratio to be determined by canvas size
scales: {
x: {
title: {
display: true,
labelString: 'Infusion Time (hours)'
},
min: 0,
max: time > 0 ? time * 1.1 : 1 // Ensure x-axis shows at least up to the infusion time
},
y: {
title: {
display: true,
labelString: 'Volume / Rate'
},
min: 0,
max: yAxisMax // Dynamic max based on data
}
},
plugins: {
legend: {
position: 'top',
},
title: {
display: true,
text: 'Volume vs. Rate Over Time'
}
}
}
});
}
function copyResults() {
var mainResultText = primaryResult.innerText.replace(" ml/hr", "").trim();
var assumptionsText = calculationAssumptions.innerText;
var textToCopy = "Infusion Rate Calculation Results:\n\n";
textToCopy += "Infusion Rate: " + mainResultText + " ml/hr\n";
textToCopy += "Total Dose Needed: " + totalDoseNeededSpan.innerText + " mg\n";
textToCopy += "Volume per mg: " + volumePerMgSpan.innerText + " ml/mg\n";
textToCopy += "Total Volume to Infuse: " + totalVolumeToInfuseResultSpan.innerText + " ml\n\n";
textToCopy += "Assumptions: " + assumptionsText + "\n\n";
textToCopy += "— Table Data —\n";
textToCopy += "Patient Weight: " + tableWeight.innerText + " kg\n";
textToCopy += "Dose per Kilogram: " + tableDosePerKg.innerText + " mg/kg\n";
textToCopy += "Drug Concentration: " + tableDrugConcentration.innerText + " mg/ml\n";
textToCopy += "Infusion Time: " + tableInfusionTime.innerText + " hr\n";
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// Initialize chart on page load
document.addEventListener("DOMContentLoaded", function() {
resetCalculator(); // Pre-fill with defaults and calculate
// Initial chart setup with default/empty data
updateChart(0, 0, 0);
});
// Add event listeners for real-time updates
weightInput.addEventListener('input', calculateInfusionRate);
dosePerKgInput.addEventListener('input', calculateInfusionRate);
drugConcentrationInput.addEventListener('input', calculateInfusionRate);
totalVolumeInput.addEventListener('input', calculateInfusionRate);
infusionTimeHoursInput.addEventListener('input', calculateInfusionRate);
// FAQ toggle functionality
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});
});
// Chart library – ensure you have Chart.js included if using this script block alone.
// For a self-contained HTML file, Chart.js needs to be embedded or linked.
// Assuming Chart.js is available globally. If not, you'd need to add:
//
// Or embed Chart.js source directly if required.
// For this example, we assume it's available.
// — Chart.js embedding (for self-contained HTML) —
// You would typically include this script tag BEFORE your main script block.
//
// If Chart.js is not externally available, you'd have to inline its source, which is very extensive.
// The provided HTML structure assumes Chart.js is accessible.
// For a truly single-file solution without external dependencies, SVG charts would be preferred.
// As a fallback, this assumes Chart.js is available or linked in the final HTML structure.