TTL Tip 9: Chest Drain Before CT? Think, Decide, Communicate

Not every pneumothorax or haemothorax needs a chest drain before CT. But some absolutely do.

One of the common dilemmas in the resus room is whether to place a chest drain before CT in a trauma patient with a suspected or known pneumothorax or haemothorax diagnosed on clinical examination or ultrasound. For some patients, this decision is obvious, but for many it requires balancing risk, and that responsibility often falls to the TTL. Here are top tips on making the right call.

The Easy Decisions

Drain before CT

If there are clear signs of compromise, get on with it:

Hypoxia
Hypotension
Suspected large haemothorax
Ventilated patient
Bilateral pneumothoraces

These patients are at risk of deterioration in transfer or in the scanner. On balance, it is better to manage it now rather than later, and ideally not in a rush in the middle of radiology when they deteriorate further.

Go straight to CT

At the other end:

Minimal symptoms
Stable physiology
Uncertain diagnosis

In these patients, placing a drain risks delay without benefit. Getting the patient through the scanner is the priority and you don’t want to be sitting on a serious injury doing a slow chest drain before getting a diagnosis.

The Difficult Middle

This is why you are there, and why being a TTL is rarely straightforward. You need to use judgement and experience to balance risks and come to a sensible decision:

Mild physiological disturbance (e.g. tachycardia)
Large pneumothorax or haemothorax seen on ultrasound
Not overtly unstable

For these patients you need to balance your decision as there are pros and cons for early or late intervention. Here’s the trade-off in the decision making.

The Trade-Off

Insert a drain first

Definitive management
Reduces risk of deterioration in CT
Diagnostic clarity

Go to CT without a drain

Avoids 20–40 minute delay in an awake patient (you may think you’re quicker, but I’ve timed you and most of the time you’re not!)
Earlier diagnosis of other injuries
Easier patient movement

And remember:

Many patients are already 30–120 minutes post-injury. The short transfer-to-CT window may be lower risk than we think.

What Does the Evidence Say?

Practice is changing.

Observational data suggest that many traumatic pneumothoraces can be managed conservatively, with a large proportion not requiring intervention (PMC)
A 2023 study found that selected small traumatic pneumothoraces managed with observation had similar outcomes but shorter hospital stays compared to chest drains (PubMed)
Systematic reviews suggest that observation can be as safe as chest tube drainage in stable patients (PMC)

There is now a major UK RCT underway (CoMiTED) asking exactly this question:
→ CoMiTED trial overview

The evidence base is changing from the days when I first did ATLS when everyone got a chest drain!.

Not all pneumothoraces need immediate drainage — even in trauma.

If You Go to CT Without a Drain

This is not doing nothing. It is active risk management.

Take equipment (all these should be easily accessible in your trauma transfer bag):
- Large-bore cannula
- Scalpel
- Chest seal
- Finger (for finger thoracostomy)
Monitor continuously
Be ready to intervene immediately
Be prepared to abandon CT and return
Send someone with the skills to identify deterioration and intervene with the patient to the scanner (I’m usually going too as TTL).

What about thoracostomies?

Some ventilated patients will arrive with a thoracostomy placed by the prehospital team. It is obviously quicker to place a tube through that thoracostomy than to start from scratch — but it will still take you longer than you think.

My view is that all of the above applies whether or not a thoracostomy is already in place. If the patient is oxygenating and ventilating adequately, you can still go to CT without inserting a tube. The evidence is right there: they’ve just travelled from scene to ED like that, so we already know it’s working.

If the patient is compromised, or there are delays, then sure, crack on.

What about a chest Xray before CT?

That’s a good question, but one for another day. We don’t do this, and have not for over a decade, but I know other services do. In a future TTL tips we might address why we rarely (if ever) do this before CT.

The TTL Role

This is a team leader decision. There is no absolute rule here, but the evidence is clear that a pneumothorax or haemothorax alone is not an indication for a drain before CT so you have to balance risk of deterioration against risk of delay. Beware the clinician who wants to do the procedure because they want to do it, rather than because the patient needs it. The patient will get a drain at some point, but it’s up to you to decide when.