Lines, Tubes & Devices
- Every line, tube, and device has a job and a "where it's supposed to live." Your job is to confirm it got there.
- Read each one the same way every time: name it, trace it from outside the body inward, and check the tip.
- The tip is the punchline. Most dangerous mistakes are a tip that ended up somewhere it shouldn't.
- Devices love to hide pathology. Always finish by checking what the hardware might be covering up.
Open any chest X-ray from an intensive care unit and it can look like someone emptied a tackle box onto the patient. Wires, tubes, clips, and mystery lines crisscross everything. It is genuinely intimidating the first time. But here's the comforting secret: each piece of plastic is just a tool with one job, and reading it is less like memorizing trivia and more like checking whether the extension cord actually reached the outlet.
This page is about the approach — the same calm routine you run on every device, every time, so you never have to improvise on a sick patient at 3 a.m.
The whole skill in one sentence
For any device, ask three questions in order: What is it? Where does it go? Where is the tip? That's it. Name the hardware, follow its course from the skin inward, and then judge the business end. The tip is almost always where the trouble — or the relief of "phew, that's fine" — lives.
Think of it like tracking a garden hose across a messy yard. You don't panic at the tangle; you find one end and walk it to the other. A line you can't trace is a line you can't trust.
Step 1 and 2: Name it, then trace it
Naming comes first because the rules change completely depending on what you're looking at. A breathing tube and a feeding tube can sit a centimeter apart and have opposite "correct" destinations. Misname the device and every judgment after it is wrong.
Once named, trace the course. Most lines and tubes carry a thin radiopaque stripe precisely so you can follow them on film — they show up bright white because metal and dense plastic eat the X-ray beam, the same reason bone looks white in the four radiographic densities. Follow that stripe like a trail of breadcrumbs. Watch for kinks, loops, or a course that suddenly veers somewhere anatomy says it shouldn't.
A clean trace answers a sneaky question: is this one line, or two overlapping? In a crowded chest, two devices can superimpose into a confusing mess. Walking each course individually untangles them.
Step 3: The tip is the punchline
Naming and tracing are setup. The tip is the joke's payoff — and the part you'll be asked about. Here's the rough cast of characters and where their tips are meant to land.
| Device | Roughly where the tip belongs |
|---|---|
| Endotracheal (breathing) tube | In the trachea, above where it splits into the two main bronchi (the carina) — not down one side. |
| Central venous line | In a large central vein near the heart, not curled back or off in a small vessel. |
| Nasogastric / feeding tube | Following the esophagus down past the diaphragm into the stomach — never veering into a bronchus. |
| Chest tube | In the pleural space, aimed at the air or fluid it's meant to drain. |
These are teaching landmarks, not exact rulers — every institution and reference has its own preferred margins, so learn the principle and then your local standard. The principle that never changes: a tip in the wrong compartment is a problem until proven otherwise.
The scariest miss is a feeding tube that wandered into the airway instead of the esophagus. Pouring liquid feed into a lung is exactly as bad as it sounds. If a "feeding" tube's course heads toward a bronchus or its tip sits in the lung, sound the alarm before anyone uses it.
The complications that ride along
Some devices don't just sit there politely — putting them in can cause problems of its own. A line placed into the chest can nick a lung and cause a pneumothorax, so after any new central line you specifically hunt for air where it shouldn't be. The follow-up film isn't a formality; it's the safety check.
Treat every "post-procedure" film as a deliberate hunt for the known complications of that procedure, not a casual glance. The radiograph after a central line exists to answer two questions: did the tip land right, and did we drop a lung?
This is why the dedicated chest pages on misplaced lines and tubes and central lines and ports are worth a visit once this routine feels natural — they go device-by-device into the specific danger zones.
Don't let the hardware hypnotize you
Here's the trap that catches everyone, including people who should know better: you get so absorbed in chasing tubes that you forget to read the actual patient. The lines are visually loud. The pneumonia they're sitting on top of is quiet. Devices are world-class at hiding the very findings you were asked to look for.
So bolt one final move onto your routine: after you've cleared the hardware, deliberately re-examine the lungs, heart, and bones as if the devices weren't there. Fold this into your usual approach to the chest X-ray so it never gets skipped.
If you remember nothing else: name it, trace it, check the tip — then look past the hardware at the human underneath it. The plastic is rarely the point. It's just there to tell you the patient is sick enough to need it.