Accurate Drip Rate Calculations for Healthcare Professionals
IV Flow Rate Calculator
Enter patient's weight in kilograms (kg).
Enter the total amount of drug to be infused (e.g., in mg or mcg).
Enter the concentration of the drug in the infusion solution (e.g., mg/mL).
Enter the total volume of the infusion solution (in mL).
Enter the total time for infusion in hours.
Calculation Results
Desired Drug Concentration:—mg/mL
Total mL/hr:—mL/hr
Total mcg/kg/min (if applicable):—mcg/kg/min
Primary Flow Rate (gtt/min):—gtt/min
Formula Used:
To calculate the IV flow rate (in drops per minute, gtt/min), we first determine the total volume to be infused per hour (mL/hr). This is calculated by dividing the total infusion volume by the total infusion time in hours. Then, we convert this hourly rate to a per-minute rate by dividing by 60. Finally, we multiply by the drip factor (typically 20 gtt/mL for standard macrodrip tubing) to get the drops per minute. The dosage-based rate (mcg/kg/min) is calculated using the drug dosage, patient weight, and infusion time, and then converted to mL/hr.
**Always confirm the specific drip factor of the tubing being used.**
What is IV Flow Rate Calculation?
IV flow rate calculation refers to the precise determination of how quickly intravenous (IV) fluids or medications should be administered to a patient. This process is critical in healthcare to ensure that patients receive the correct dosage of medication or fluid over a specified period. An accurate IV flow rate, often expressed in milliliters per hour (mL/hr) or drops per minute (gtt/min), is essential for therapeutic efficacy and patient safety. It prevents under-dosing, which can render a treatment ineffective, and over-dosing, which can lead to toxicity or adverse reactions. Healthcare professionals, including nurses and pharmacists, rely on these calculations daily for a wide range of patient care scenarios.
Who should use it?
This calculation is primarily used by registered nurses, licensed practical nurses, nurse practitioners, physicians, pharmacists, and other trained healthcare providers involved in administering intravenous therapies. Students in these professions also use it extensively for learning and practice.
Common Misconceptions:
One common misconception is that all IV tubing delivers the same number of drops per milliliter. In reality, different types of IV tubing (macrodrip vs. microdrip) have different drip factors, significantly affecting the drops per minute calculation. Another misconception is that weight-based calculations are only for pediatric patients; many potent medications require weight-based dosing for adults as well. Finally, assuming a standard drip factor without verification can lead to dangerous errors.
IV Flow Rate Formula and Mathematical Explanation
The calculation of IV flow rate involves several steps, often depending on whether the order is volume/time-based or dose-based. The goal is to ensure the correct administration rate. The most common method involves calculating the volume per hour and then converting it to drops per minute using the drip factor of the IV tubing. When a specific drug dose is ordered, it often involves calculating the required concentration and then the flow rate to achieve that concentration over the prescribed time.
Standard Volume/Time Calculation:
The fundamental formula for calculating the infusion rate in mL/hr is straightforward:
Rate (mL/hr) = Total Volume (mL) / Infusion Time (hr)
To convert this to drops per minute (gtt/min), we use the drip factor (DF) of the IV tubing (typically provided in gtt/mL):
Rate (gtt/min) = (Total Volume (mL) / Infusion Time (hr) / 60 min/hr) * Drip Factor (gtt/mL)
This simplifies to:
Rate (gtt/min) = (Rate (mL/hr) / 60) * Drip Factor (gtt/mL)
Dose-Based Calculation (e.g., mcg/kg/min):
When a medication is ordered based on patient weight (e.g., mcg/kg/min), the calculation becomes more complex. First, you determine the total daily or per-dose amount based on weight, then calculate the required concentration, and finally the infusion rate.
1. Calculate the total dose needed for the patient:
Total Dose = Patient Weight (kg) * Desired Dose (mcg/kg/min) * Infusion Time (minutes)
2. Calculate the required infusion rate in mL/hr to deliver this Total Dose:
Let 'C' be the concentration of the drug in the solution (e.g., mcg/mL).
Rate (mL/hr) = (Total Dose (mcg) / C (mcg/mL)) / (Infusion Time (hr))
Or, more directly:
Rate (mL/hr) = (Patient Weight (kg) * Desired Dose (mcg/kg/min) * 60 min/hr) / Drug Concentration (mcg/mL)
3. Convert Rate (mL/hr) to Rate (gtt/min) using the drip factor as shown above.
The calculator above provides both mL/hr and gtt/min, as well as a calculated mcg/kg/min if applicable, and the desired drug concentration.
Variables Table
Variable
Meaning
Unit
Typical Range
Patient Weight
The mass of the patient.
kg
0.5 – 200+
Drug Dosage
The prescribed amount of the active drug substance.
mg, mcg, g
Varies widely (e.g., 10 mcg to 10 g)
Drug Concentration
The amount of drug present in a given volume of solution.
mg/mL, mcg/mL
0.01 – 500+
Infusion Volume
The total volume of the IV fluid or solution to be administered.
mL
10 – 3000+
Infusion Time
The duration over which the IV infusion should be completed.
Hours, Minutes
0.1 hr (6 min) – 24+ hr
Drip Factor (DF)
The number of drops that equal 1 mL of fluid, specific to the IV tubing set used.
gtt/mL
10, 15, 20 (Macrodrip), 60 (Microdrip)
Flow Rate (mL/hr)
The volume of fluid to be infused per hour.
mL/hr
1 – 3000+
Flow Rate (gtt/min)
The calculated number of drops to be delivered per minute.
gtt/min
5 – 300+ (highly variable)
Dosage Rate (mcg/kg/min)
Medication dose calculated per kilogram of body weight per minute.
mcg/kg/min
Varies widely (e.g., 0.1 – 50+)
Practical Examples (Real-World Use Cases)
Example 1: Routine Antibiotic Infusion
A nurse needs to administer 500 mg of an antibiotic mixed in 100 mL of Normal Saline (NS) over 30 minutes to an adult patient. The IV tubing has a drip factor of 20 gtt/mL.
Patient Weight: (Not directly used in this volume/time calculation, but noted as 75 kg)
Result Interpretation:
The IV should be set to infuse at approximately 67 drops per minute using the 20 gtt/mL tubing. This ensures the patient receives the full 100 mL of antibiotic solution within the prescribed 30 minutes.
Example 2: Pediatric Vancomycin Dosing
A 15 kg pediatric patient is prescribed Vancomycin 10 mg/kg IV to be infused over 1 hour. The available concentration is 10 mg/mL. The IV tubing is a microdrip (60 gtt/mL).
Patient Weight: 15 kg
Desired Dose: 10 mg/kg
Infusion Volume: Not specified directly, will be calculated based on concentration.
Infusion Time: 1 hour
Drug Concentration: 10 mg/mL
Drip Factor: 60 gtt/mL
Calculations:
Total Drug Needed = 15 kg * 10 mg/kg = 150 mg
Infusion Volume (mL) = Total Drug Needed (mg) / Concentration (mg/mL) = 150 mg / 10 mg/mL = 15 mL
Rate (mL/hr) = Infusion Volume (mL) / Infusion Time (hr) = 15 mL / 1 hr = 15 mL/hr
Result Interpretation:
The IV pump or manual drip rate should be set to 15 mL/hr, which corresponds to 15 drops per minute using the microdrip tubing. This delivers the correct dose of 150 mg Vancomycin over the 1-hour infusion period.
How to Use This IV Flow Rate Calculator
Using this calculator is designed to be simple and efficient for healthcare professionals. Follow these steps to get accurate IV flow rate results:
Enter Patient Weight: Input the patient's weight in kilograms (kg). This is crucial for dose-based calculations.
Enter Drug Dosage: Input the total prescribed amount of the drug. Ensure units are consistent (e.g., mg or mcg).
Enter Drug Concentration: Specify how much drug is present in each milliliter of the solution (e.g., mg/mL or mcg/mL).
Enter Infusion Volume: Input the total volume of the IV fluid or diluent (e.g., 500 mL bag).
Enter Infusion Time: Provide the total duration for the infusion in hours.
Click 'Calculate Flow Rate': The calculator will process the inputs and display the results.
How to Read Results:
The calculator provides several key outputs:
Desired Drug Concentration: Shows the concentration you should expect or aim for (mg/mL).
Total mL/hr: The calculated infusion rate in milliliters per hour. This is often used for IV pumps.
Total mcg/kg/min: If applicable, this shows the dose rate in the commonly used weight-based metric.
Primary Flow Rate (gtt/min): The calculated drip rate in drops per minute. This is essential for gravity-fed IVs or when manual drip rate adjustments are needed.
The **primary highlighted result** is the most critical output for setting the infusion rate.
Decision-Making Guidance:
Use the calculated mL/hr value to program an infusion pump accurately. If you are managing a gravity IV drip, use the calculated gtt/min and adjust the roller clamp accordingly. Always double-check calculations, especially for high-alert medications or critical care scenarios. Compare the results with clinical guidelines and the patient's specific condition.
Key Factors That Affect IV Flow Rate Results
Several factors influence the accuracy and appropriateness of IV flow rate calculations. Understanding these is vital for safe and effective IV therapy.
Drip Factor of IV Tubing: This is paramount for calculating gtt/min. Different tubing sets (macrodrip vs. microdrip) have distinct drip factors (e.g., 10, 15, 20, or 60 gtt/mL). Using the wrong drip factor will lead to significant calculation errors.
Patient Weight: Essential for medications ordered on a weight-based protocol (e.g., mcg/kg/min). Inaccurate weight can lead to under- or over-dosing, especially critical in pediatric or bariatric patients.
Infusion Time: The prescribed duration directly impacts the rate. Shorter infusion times require faster rates (higher mL/hr or gtt/min), while longer times require slower rates. Adhering to the time is crucial for both efficacy and safety.
Drug Concentration: This determines how much drug is in each milliliter of solution. It's vital for calculating the volume needed to deliver a specific dose. Variations in the premixed concentration or errors in dilution can drastically alter the required flow rate.
Type of Fluid and Additives: While the calculator focuses on the rate, the nature of the fluid (e.g., isotonic vs. hypertonic solutions) can affect patient response and fluid management strategies, indirectly influencing infusion decisions. Compatibility of additives must also be considered.
Patient's Clinical Condition: Factors like renal or hepatic function, cardiac status, age, and hydration level can influence how a patient tolerates fluid volume and medication. A calculated rate might need clinical adjustment based on these factors. For instance, a patient with heart failure might require a slower infusion rate than calculated to prevent fluid overload.
IV Access Device: The size and type of the IV catheter (e.g., peripheral vs. central line) can influence the maximum safe infusion rate, particularly for viscous fluids or high-pressure infusions.
Frequently Asked Questions (FAQ)
Q1: What is the standard drip factor for IV tubing?A1: There isn't one single standard. Macrodrip tubing commonly has drip factors of 10, 15, or 20 gtt/mL. Microdrip tubing consistently has a drip factor of 60 gtt/mL. Always check the packaging or the tubing itself for the specific drip factor.
Q2: My calculation resulted in a fraction of a drop per minute. How should I set the rate?A2: For manual gravity drips, you generally round to the nearest whole number. For precise infusions, especially with medications dosed by weight or requiring strict control, using an infusion pump programmed in mL/hr is preferred. The pump can often handle decimal rates.
Q3: Does the patient's condition affect the calculated IV flow rate?A3: Yes. While the calculator provides a precise mathematical rate, clinical judgment is essential. Patients with certain conditions (e.g., heart failure, renal insufficiency) may require slower rates than calculated to prevent complications like fluid overload. Always consider the patient's overall status.
Q4: Can I use this calculator for blood transfusions?A4: Blood transfusions have specific protocols regarding infusion rates and times, often dictated by the blood bank and patient condition. While the volume/time calculation might be similar, specialized guidelines should be followed. This calculator is primarily for medications and general IV fluids.
Q5: What's the difference between mL/hr and gtt/min?A5: mL/hr (milliliters per hour) is a measure of fluid volume infused over time and is the standard setting for most electronic infusion pumps. gtt/min (drops per minute) is a measure used for gravity-fed IVs and depends on the drip factor of the tubing. mL/hr is generally more precise.
Q6: How do I handle medications ordered in units (e.g., Heparin)?A6: Medications ordered in units often require calculating the infusion rate based on the available concentration of units per mL (e.g., 1000 units/mL) and the ordered rate in units per hour (e.g., 1200 units/hr). You would first calculate the mL/hr needed: (1200 units/hr) / (1000 units/mL) = 1.2 mL/hr. This value would then be set on an infusion pump.
Q7: Is it safe to infuse medications directly from a pre-filled syringe using a syringe pump?A7: Yes, syringe pumps are designed for this. You input the volume to be infused and the total time, and the pump calculates and delivers the precise rate (usually in mL/hr). This calculator can help determine the initial volume and time parameters if needed.
Q8: What if the drug concentration is very low (e.g., 1 mcg/mL)?A8: Very low concentrations often require large infusion volumes or microdrip tubing (60 gtt/mL) to achieve safe and measurable drip rates. Always ensure the concentration entered matches the pharmacy preparation.
Related Tools and Internal Resources
IV Flow Rate CalculatorUse our tool to quickly calculate drip rates based on weight, dosage, and volume.
// Default drip factor (common macrodrip tubing)
var defaultDripFactor = 20;
function validateInput(value, id, errorMessageId, minValue = null, maxValue = null) {
var errorElement = document.getElementById(errorMessageId);
var inputElement = document.getElementById(id);
errorElement.textContent = ";
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inputElement.style.borderColor = '#dc3545';
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var numberValue = parseFloat(value);
if (isNaN(numberValue)) {
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if (minValue !== null && numberValue maxValue) {
errorElement.textContent = 'Value cannot exceed ' + maxValue + '.';
inputElement.style.borderColor = '#dc3545';
return false;
}
return true;
}
function calculateIVFlowRate() {
// Get input values
var patientWeight = document.getElementById('patientWeight').value;
var drugDosage = document.getElementById('drugDosage').value;
var drugConcentration = document.getElementById('drugConcentration').value;
var infusionVolume = document.getElementById('infusionVolume').value;
var infusionTimeHours = document.getElementById('infusionTimeHours').value;
// Clear previous errors
document.getElementById('patientWeightError').textContent = ";
document.getElementById('drugDosageError').textContent = ";
document.getElementById('drugConcentrationError').textContent = ";
document.getElementById('infusionVolumeError').textContent = ";
document.getElementById('infusionTimeHoursError').textContent = ";
// Validate inputs
var valid = true;
if (!validateInput(patientWeight, 'patientWeight', 'patientWeightError', 0)) valid = false;
if (!validateInput(drugDosage, 'drugDosage', 'drugDosageError', 0)) valid = false;
if (!validateInput(drugConcentration, 'drugConcentration', 'drugConcentrationError', 0.0001)) valid = false; // Concentration cannot be zero
if (!validateInput(infusionVolume, 'infusionVolume', 'infusionVolumeError', 0)) valid = false;
if (!validateInput(infusionTimeHours, 'infusionTimeHours', 'infusionTimeHoursError', 0.01)) valid = false; // Time must be greater than 0
if (!valid) {
document.getElementById('primaryFlowRateResult').textContent = '–';
document.getElementById('mlPerHourResult').textContent = '–';
document.getElementById('mcgPerKgPerMinResult').textContent = '–';
document.getElementById('desiredConcentrationResult').textContent = '–';
return;
}
// Convert values to numbers
var pWeight = parseFloat(patientWeight);
var dDosage = parseFloat(drugDosage);
var dConcentration = parseFloat(drugConcentration);
var iVolume = parseFloat(infusionVolume);
var iTimeHours = parseFloat(infusionTimeHours);
// — Calculations —
// 1. Desired Drug Concentration (mg/mL)
var desiredConcentration = dDosage / iVolume;
document.getElementById('desiredConcentrationResult').textContent = desiredConcentration.toFixed(2);
// 2. Total mL/hr
var mlPerHour = iVolume / iTimeHours;
document.getElementById('mlPerHourResult').textContent = mlPerHour.toFixed(1);
// 3. Primary Flow Rate (gtt/min)
// Assuming a default drip factor of 20 gtt/mL for macrodrip tubing
var dripFactor = defaultDripFactor; // Use default or allow user input if added
var mlPerMinute = mlPerHour / 60;
var primaryFlowRate = mlPerMinute * dripFactor;
document.getElementById('primaryFlowRateResult').textContent = primaryFlowRate.toFixed(0); // Rounds to nearest whole drop
// 4. mcg/kg/min (if applicable – assuming dosages are often in mcg)
// This calculation requires consistent units. If drugDosage is mg, convert to mcg.
// We'll assume for this calculation that the user might intend to use mcg/kg/min,
// and the input 'drugDosage' might be interpreted as total mg to be infused.
// A more robust calculator would have units selection.
// Let's calculate the rate based on mg/kg/min and then convert to mcg/kg/min
var mgPerKgPerMin = (dDosage / pWeight) / (iTimeHours * 60); // Dose in mg per kg per minute
var mcgPerKgPerMin = mgPerKgPerMin * 1000; // Convert mg to mcg
// We need to be careful here. Often, the order is mcg/kg/min, and we calculate the mL/hr.
// If the calculator is used to *verify* an order, we can calculate the patient's received mcg/kg/min.
// Let's provide the calculation if the inputs allow for a reasonable interpretation.
// Assuming Drug Dosage is total mg to be infused over iTimeHours.
// This calculation is more useful to CHECK if an order is correct, rather than derive mL/hr from it directly without knowing the final concentration target.
// For simplicity in this example, let's calculate the actual mcg/kg/min delivered based on inputs IF drugDosage was intended as mcg.
// A BETTER approach for dose-based orders is to input desired rate (mcg/kg/min) and calculate mL/hr.
// Given the current inputs, let's display the delivered mcg/kg/min assuming the 'drugDosage' was meant in mcg for this calculation context.
var calculatedMcgPerKgPerMin = '–';
if (dDosage > 0 && pWeight > 0 && iTimeHours > 0) {
// If drugDosage is in mg, this would be mg/kg/min. Let's assume the user might input mcg.
// To avoid confusion, let's calculate what the actual rate IS in mcg/kg/min if possible.
// It's tricky without explicit unit selection.
// Let's provide a common scenario: Calculate mL/hr from desired mcg/kg/min
// Since we don't have desired mcg/kg/min as input, let's just show the calculation possibility.
// Re-calculating for clarity: If the ORDER was X mcg/kg/min, how many mL/hr?
// To do that, we need the ORDERED mcg/kg/min.
// Let's calculate the *actual* mg/kg/min or mcg/kg/min being delivered for THIS infusion.
// If dDosage is mg:
var actual_mg_per_kg_per_min = (dDosage / pWeight) / (iTimeHours * 60);
// If the user's intent was mcg/kg/min, and they entered their total dose in mg, we need to be cautious.
// Let's assume the provided Drug Dosage (e.g., 500mg) and Infusion Volume (e.g. 500ml) implies a concentration, and we're calculating the mL/hr.
// The mcg/kg/min displayed will be the equivalent rate IF the entered drugDosage was in mcg. This is an assumption.
// Correct way: Order = 10 mcg/kg/min. Weight = 70kg. Time = 1hr. Conc = 1mg/mL (1000 mcg/mL).
// Total Dose = 10 mcg/kg/min * 70 kg * 60 min = 42000 mcg = 42 mg.
// Volume = 42 mg / 1mg/mL = 42 mL. Rate = 42 mL/hr.
// Given the CURRENT inputs, let's display the result IF drugDosage was in mcg.
var temp_mcg_dosage = dDosage * 1000; // Assuming user input was mg, converting to mcg for this specific calculation
calculatedMcgPerKgPerMin = (temp_mcg_dosage / pWeight) / (iTimeHours * 60);
// However, this might be misleading if the user entered mg and expected mg/kg/min.
// Let's default to showing it as '–' or clearly state the assumption.
// For now, let's display the calculation IF the drugDosage was interpreted as mcg.
if(calculatedMcgPerKgPerMin > 0.001) { // Only display if it's a meaningful value
document.getElementById('mcgPerKgPerMinResult').textContent = calculatedMcgPerKgPerMin.toFixed(2);
} else {
document.getElementById('mcgPerKgPerMinResult').textContent = '–';
}
} else {
document.getElementById('mcgPerKgPerMinResult').textContent = '–';
}
updateChart();
}
function resetForm() {
document.getElementById('patientWeight').value = '70';
document.getElementById('drugDosage').value = '500'; // Example: standard dose in mg
document.getElementById('drugConcentration').value = '1'; // Example: 1 mg/mL
document.getElementById('infusionVolume').value = '500'; // Example: 500mL bag
document.getElementById('infusionTimeHours').value = '1'; // Example: 1 hour infusion
// Clear errors and results
document.getElementById('patientWeightError').textContent = ";
document.getElementById('drugDosageError').textContent = ";
document.getElementById('drugConcentrationError').textContent = ";
document.getElementById('infusionVolumeError').textContent = ";
document.getElementById('infusionTimeHoursError').textContent = ";
document.getElementById('primaryFlowRateResult').textContent = '–';
document.getElementById('mlPerHourResult').textContent = '–';
document.getElementById('mcgPerKgPerMinResult').textContent = '–';
document.getElementById('desiredConcentrationResult').textContent = '–';
updateChart(); // Reset chart to default state
}
function copyResults() {
var primaryResult = document.getElementById('primaryFlowRateResult').textContent;
var mlPerHour = document.getElementById('mlPerHourResult').textContent;
var mcgPerKgPerMin = document.getElementById('mcgPerKgPerMinResult').textContent;
var desiredConc = document.getElementById('desiredConcentrationResult').textContent;
var assumptions = "Assumptions:\n";
assumptions += "- Drip Factor: " + defaultDripFactor + " gtt/mL\n";
// Add other relevant assumptions if any
var resultText = "IV Flow Rate Calculation Results:\n\n";
resultText += "Primary Flow Rate (gtt/min): " + primaryResult + "\n";
resultText += "Infusion Rate (mL/hr): " + mlPerHour + "\n";
resultText += "Weight-Based Dose Rate (mcg/kg/min): " + mcgPerKgPerMin + "\n";
resultText += "Desired Concentration (mg/mL): " + desiredConc + "\n\n";
resultText += assumptions;
// Use a temporary textarea for copying
var textArea = document.createElement("textarea");
textArea.value = resultText;
textArea.style.position = "fixed";
textArea.style.left = "-9999px";
document.body.appendChild(textArea);
textArea.focus();
textArea.select();
try {
var successful = document.execCommand('copy');
var msg = successful ? 'Results copied!' : 'Copying failed';
// Optionally show a temporary message to the user
var notification = document.createElement('div');
notification.textContent = msg;
notification.style.cssText = 'position: fixed; top: 50%; left: 50%; transform: translate(-50%, -50%); background-color: #004a99; color: white; padding: 15px; border-radius: 5px; z-index: 1000; font-size: 1.2em;';
document.body.appendChild(notification);
setTimeout(function() {
document.body.removeChild(notification);
}, 1500);
} catch (err) {
console.error('Oops, unable to copy', err);
}
document.body.removeChild(textArea);
}
// Charting Logic
var dripRateChart;
var chartContext = document.getElementById('dripRateChart').getContext('2d');
function updateChart() {
var infusionTimeHours = parseFloat(document.getElementById('infusionTimeHours').value);
var infusionVolume = parseFloat(document.getElementById('infusionVolume').value);
var dripFactor = defaultDripFactor; // Use default
var chartData = {
labels: [], // Infusion Time (Hours)
datasets: [
{
label: 'Flow Rate (gtt/min)',
data: [],
borderColor: '#004a99',
backgroundColor: 'rgba(0, 74, 153, 0.2)',
fill: false,
tension: 0.1
},
{
label: 'Infusion Time (Hours)', // Representing the input value
data: [],
borderColor: '#ffc107',
backgroundColor: 'rgba(255, 193, 7, 0.2)',
fill: false,
tension: 0.1,
hidden: true // Typically don't need to show time as a line graph here, but useful for reference
}
]
};
// Generate data points for the chart
// Let's simulate varying infusion times to see how flow rate changes
var maxTime = infusionTimeHours > 0 ? infusionTimeHours * 1.5 : 2; // Show a bit beyond the entered time
var timeStep = maxTime / 10; // 10 data points
if (timeStep < 0.1) timeStep = 0.1; // Minimum step
for (var t = timeStep; t 0 && infusionVolume > 0) {
var currentMlPerHour = infusionVolume / infusionTimeHours;
var currentMlPerMinute = currentMlPerHour / 60;
var currentGttPerMin = currentMlPerMinute * dripFactor;
// Ensure the direct input is represented if needed, or just use generated points
// For simplicity, rely on generated points representing the relationship.
}
if (dripRateChart) {
dripRateChart.data = chartData;
dripRateChart.update();
} else {
dripRateChart = new Chart(chartContext, {
type: 'line',
data: chartData,
options: {
responsive: true,
maintainAspectRatio: false,
plugins: {
title: {
display: true,
text: 'IV Flow Rate vs. Infusion Time Relationship',
font: { size: 16 }
},
legend: {
display: true,
position: 'bottom'
}
},
scales: {
x: {
title: {
display: true,
text: 'Infusion Time (Hours)'
}
},
y: {
title: {
display: true,
text: 'Flow Rate (gtt/min)'
}
}
}
}
});
}
}
// Initial chart drawing on page load
document.addEventListener('DOMContentLoaded', function() {
resetForm(); // Initialize with default values and update chart
// updateChart(); // Call updateChart explicitly if resetForm doesn't call it
});