Chest Tube Size Calculator
Select chest tube size (Fr) based on indication, patient type, and weight with insertion site and drainage system recommendations.
About this calculator
This calculator recommends a chest tube (thoracostomy tube) size in French (Fr) based on the clinical indication and, for pediatric patients, an age estimate derived from weight. For adult patients (the default Patient Type), the recommended size is a fixed value per indication -- 22 Fr for pneumothorax, 36 Fr for hemothorax, 32 Fr for empyema, and 16 Fr for pleural effusion -- and Patient Weight has NO effect on the adult recommendation at all, since the underlying logic only incorporates weight when estimating tube size for pediatric patients. For pneumothorax specifically, this 20-24 Fr recommendation reflects traditional teaching, kept here as the default -- but current guidance has moved on: the British Thoracic Society's 2023 Pleural Disease Guideline (its most recent full update, in the society's journal Thorax) favors small-bore (<=14 Fr) drainage as first-line for pneumothorax, not a 20-24 Fr tube. Traditional teaching separately favors large-bore tubes (32-40 Fr) for hemothorax, on the theory that a wider lumen resists clot occlusion better than a narrow one; this calculator follows that traditional sizing too.
A growing body of randomized trial evidence, including a 2021 RCT (Bauman/Kulvatunyou et al.) and a 2025 meta-analysis (Granieri et al.), has found 14 Fr pigtail catheters non-inferior to 28-40 Fr chest tubes for traumatic hemothorax on failure rate and complications, with shorter procedure time -- though that evidence base is not yet large enough to be considered definitive, and no formal EAST guideline currently mandates a specific tube size for hemothorax. So both the pneumothorax and hemothorax recommendations here reflect traditional sizing rather than the most current evidence, but the pneumothorax case is the more clearly superseded one: BTS 2023 is a published guideline recommendation, not just emerging trial evidence. Regardless of size, standard insertion site for all indications is the "safe triangle": the 4th-5th intercostal space at the anterior-to-mid axillary line.
Medical Disclaimer
This calculator is for informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making decisions about your health. Never disregard professional medical advice or delay seeking it because of results from this tool.
Inputs
Results
Recommended Tube Size (Fr)
22
Figures current as of 2023. Source: British Thoracic Society. BTS Guideline for Pleural Disease 2023. Thorax. 2023.
How to Use This Calculator
- Select the Indication (pneumothorax, hemothorax, empyema, or effusion) from the dropdown.
- Select Patient Type (Adult or Pediatric) and enter Patient Weight (kg) for pediatric sizing.
- Review Recommended Tube Size (Fr), Minimum and Maximum acceptable sizes.
- Check Insertion Site guidance (safe triangle for pneumothorax: 4th-5th ICS, anterior axillary line).
- Review the recommended Connection type (Heimlich valve or suction) and Suction Pressure (cmH2O), which are determined automatically from the indication.
What each input means
- Indication
- The clinical indication drives recommended tube size and connection type.
- Patient Type
- Pediatric sizing is estimated from weight; adult sizing is fixed by indication.
- Patient Weight
- Weight in kg. Used for pediatric tube size estimation.
What each result means
- Recommended Tube Size (Fr)
- Optimal chest tube size in French for the given indication.
- Minimum Size (Fr)
- Lower end of acceptable range.
- Maximum Size (Fr)
- Upper end of acceptable range.
- Insertion Site (1 = Safe Triangle)
- 4th-5th intercostal space, mid-axillary line (safe triangle).
- Connection (2=Heimlich, 3=Suction)
- Recommended drainage system connection type. This calculator's simplified indication-only model never recommends a plain underwater seal without suction or valve -- that choice depends on whether the pneumothorax is stable/ambulatory, which isn't an input here.
- Suction Pressure (cmH2O)
- Recommended suction pressure. 0 if no suction needed.
How this is calculated
Worked example, using the default values
- Identify Input ParametersIndication = 1, Patient Type (1=Adult, 2=Pediatric) = 1, Patient Weight (kg) = 70 = 3 input(s) provided
- Calculate Recommended Tube Size22 = 22
- Calculate Minimum Size20 = 20
- Calculate Maximum Size24 = 24
Figures and sources
- BTS Pleural Disease Guideline 2023 (small-bore vs. large-bore chest drain sizing) (2023) — British Thoracic Society. BTS Guideline for Pleural Disease 2023. Thorax. 2023.
Engine last updated . Checked against 1 independently-derived test — how we verify calculators. Built by Paul Gunder, a software engineer, not a licensed financial, medical, or legal professional.
Frequently Asked Questions
Does a patient's weight change the recommended chest tube size for an adult?
No. For adult patients (the default Patient Type), the recommended tube size is a fixed value determined entirely by the indication -- 22 Fr for pneumothorax, 36 Fr for hemothorax, 32 Fr for empyema, 16 Fr for pleural effusion -- and Patient Weight plays no role in that calculation. Weight only enters the sizing logic when Patient Type is set to Pediatric, where it's used to estimate the child's approximate age.
Is a large-bore chest tube always necessary for hemothorax?
Traditional teaching recommends large-bore tubes (32-40 Fr) for hemothorax on the theory that a wider lumen better resists occlusion by clotted blood, and this calculator follows that traditional sizing. However, a growing body of randomized trial evidence -- including a 2021 RCT and a 2025 meta-analysis -- has found 14 Fr pigtail catheters non-inferior to large-bore tubes for traumatic hemothorax, with shorter placement time. That evidence isn't yet considered definitive enough to have produced a formal guideline mandating a specific size, so practice varies by institution.
Where is the standard insertion site for a chest tube regardless of indication?
The standard insertion site is the "safe triangle": the 4th or 5th intercostal space at the anterior-to-mid axillary line, bordered by the pectoralis major, the latissimus dorsi, and a line at the level of the nipple. This location is used consistently across pneumothorax, hemothorax, empyema, and effusion, avoiding major vessels, nerves, and abdominal organs that are at greater risk at lower or more medial insertion points.
Why does pneumothorax typically need a smaller chest tube than hemothorax?
A pneumothorax is draining air, which flows easily through a narrower tube, while a hemothorax is draining blood and clot, which needs a wider lumen to avoid occlusion. That's why this calculator recommends roughly 20-24 Fr for pneumothorax versus the larger 32-40 Fr traditionally used for hemothorax. But even 20-24 Fr is larger than current guidance recommends for pneumothorax specifically: the British Thoracic Society's 2023 Pleural Disease Guideline favors small-bore (<=14 Fr) drainage as first-line for pneumothorax. This calculator's 20-24 Fr default reflects traditional teaching, not the current BTS recommendation -- see the earlier question on hemothorax sizing for the parallel (but separately evidenced) large-bore-vs-small-bore debate.
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