How to manage chest tubes (5-minute version)

I am no expert in chest tubes, and will add the caveat that for this particular post I really hope everything is correct! If it’s not, let me know! See this post on the different kinds of chest tubes. This is a great but long nursing resource from RN.com.

You’ve placed a chest tube: great! Now you hook it up to some weird box thing that is called a drainage system…now what? Knowing how chest tubes used to work helps you understand the box thing.

This picture is taken from a truly excellent little video on how chest tube drainage works:

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ThScreen Shot 2017-01-26 at 6.01.21 PM.pngere used to be 3 separate bottles hooked up to the chest tube itself: Bottle #1 is where the patient’s empyema fluid or blood leaked into. Bottle #2 is the waterseal: air is forced to travel through water and can only move in one direction (it cannot move back into the patient). Bottle #3 sets suction power based on how much water is in the bottle–more water=less suction, less water=more suction, and you need to make sure the suction power is just right. You can see how the drainage system has evolved over time on the right.

Should patients be “placed to waterseal” or “placed to -20 suction?” 

“Place to waterseal”= don’t be too crazy with drainage, which is appropriate for most pleural effusions or a mild pneumothorax. If the lung is not fully expanded, you can “turn up the suction.”If you apply suction too aggressively, you put the patient at risk for re-expansion pulmonary edema.

How do I know if there is an “air leak” and what the eff does it mean? 

An air leak is present if there is bubbling in the waterseal chamber when the suction is clamped/on waterseal–this indicates there is positive pressure coming from the pleural space=air getting into the pleural space. Intermittent bubbling with expiration (when pleural pressure is highest in the non-ventilated patient) may be normal, but a continuous air leak is pathological.

Causes include:

  • ruptured bleb (severe emphysema)
  • simple traumatic pneumothorax (from placing the chest tube)
  • a leak in the actual tubing system
  • mechanical ventilation (may see decreased tidal volumes, failure of PEEP increase)
  • bronchopleural fistula (usually more severe or continuous)
  • lung entrapment vs. trapped lung

NB: if your patient has a persistent air leak, think twice about pulling their chest tube because if you do, you may cause a recurrent pneumothorax.

What is “tidaling?” 

You may see movement in the waterseal chamber with respiratory variation. It’s the water being sucked back towards the lung with inspiration due to negative inspiratory pressure. (In mechanically ventilated patients, it’s the opposite.)

 

How do I know when the tube can be taken out? 

In a 2013 study out of Michigan State, the team found it is reasonable to remove chest tubes when drainage <200 ml/day, on waterseal, with no air leak. In stable patients on the floor, theoretically you don’t need a chest x-ray after removal, but given our litigious society, everyone gets one. In mechanically ventilated patients, you should get a chest x-ray 1-3 hours after removal.

What do I do if the tube falls out? 

Use common sense: cover the area and prepare to re-insert a chest tube. Maintain sterility. The patient is at risk of a tension pneumothorax, so someone should stay with them for close monitoring. More troubleshooting at this nursing website.

 

 

What is vent dyssynchrony?

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One of the problems that is not uncommon in patients on ventilators is correcting for “vent dyssynchrony.” Vent dyssynchrony is when the patient’s demand for oxygen is not being met by the ventilator.

Why? Consider three factors:

  • LENGTH OF BREATH (how long is inspiration?)
  • TIMING OF BREATH (when is the switch to expiration/inspiration?)
  • ADEQUATE FLOW (how big are the volumes?)

If there are problems with any of those things, dyssynchrony can result. Dyssynchrony results in those annoying beeps you hear from the vent. This is called “triggering the vent.” This can happen if:

  • ineffective triggering: PEEP is too high, musculoskeletal weakness
  • inappropriate triggering: tidal volume is too low, inspiratory time is too short or flow is too low, coughing or hiccups
  • autotriggering: coughing, hiccups, shivering, seizures

What should you do about it? The best thing would be to correct the underlying problem. You may have to change the vent setting, the flow rate or tidal volume, or the insp/exp times. Sometimes, all you need to do is change the trigger sensitivity threshold!

As with many of my posts, I turn to Life in the Fast Lane as a reference.

 

True or false: “I had the BCG vaccination so I need to get a chest x-ray instead of the PPD”

False! Employee health workers may say that people who have gotten the BCG vaccination–usually from Asia, Africa, or the Caribbean–do not have reliable PPD readings and therefore need chest x-rays. One magazine article reports: “Current Occupational Safety and Health Administration (OSHA) regulations do not require periodic chest x-rays for a health-care worker who is PPD-positive unless symptoms develop.”

Furthermore, according to Ethnomed:

“Prior vaccination with BCG is not a contraindication to TB skin testing, and the CDC guidelines recommend ignoring BCG status when interpreting skin test results and selecting candidates for latent TB treatment. Although BCG vaccination can turn a skin test positive, reactivity due to BCG vaccination wanes over time. If it has been more than 5 years since vaccination, a positive skin test is more likely due to TB infection than vaccination. Furthermore, the larger the size of the PPD reaction, the less likely it is due to BCG. A recent meta-analysis found that reactive skin tests more than 15 years since vaccination or with more than 15 mm of induration were unlikely to be due to prior BCG vaccination.

Interferon-based blood tests such as the QuantiFERON® -TB Gold avoid the possibility of false-positives occurring from BCG vaccination, since cross-reactivity does not occur.”

Be warned that the Quant Gold may come back as “indeterminate” or “borderline” and then you may be in a bit of a pickle and have to get a chest x-ray anyway.

Questions you should make sure to ask someone who has had a past positive PPD:
1. How long ago was it?
2. Have you ever received the BCG vaccine?
3. Did you ever receive treatment for latent TB? (isoniazid)
4. Have you ever had a chest x-ray previously?

 

What is mucus plugging?

If you have a patient with acute O2 desat, one of the things you should consider is: do they have thick secretions? Do they have poor air movement? Could they have a mucus plug?

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Abundant thick airway secretions may become impacted in the lower airways, causing obstruction and atelectasis. Mucus plug may cause lung collapse .

If the patient is on a ventilator, you may be able to detect excessive airway secretions on the flow-volume loop, which will show a sawtooth pattern representing intermittent changes in airway resistance.

How can you protect against mucus plugs? Give patients humidified O2. Do pulmonary toilet, with frequent airway suctioning. Give medications like glycopyrrolate, which can thin secretions.

 

What’s the difference between a submassive and massive pulmonary embolism?

Submassive vs massive PE: this is an old classification that isn’t helpful anymore.

“Submassive” means low to intermediate risk, hemodynamically stable patient with no standard for how big or little the clot is.

“Massive” means high-risk, hemodynamically unstable, and again, no standard for how big or little the clot is.

We freak out about saddle emboli, but a saddle embolus isn’t necessarily high-risk. What is concerning? Elevated troponins or BNP, or signs of RV strain on the ECHO. You may even see RV strain on CT if the ventricle is larger or the septum is bulging inversely; reflux of hepatic contrast indicates that RV filling pressures are higher.

What to do with high-risk patients? Consider giving TPA. This shouldn’t be a knee-jerk reaction due to possible bleeding risk. That being said, there is some evidence such as the PEITHO trial showing that TPA might have a role in intermediate-risk PEs as well.

What are mechanical ventilators? Part 3: when to extubate

Every intubated patient deserves a spontaneous breathing trial every day!

When should you think about extubating someone?

  1. mental status? Do they have the cortical connections to breathe on their own? Are they hypoventilating?
  2. M/S strength: do they have good respiratory muscles?
  3. Cough/gag/secretions?
  4. Is their lung disease resolved?

There are several ways to “wean” someone off a vent:

  1. T-piece for 30 mins. CHF.
  2. PSV 8/5 for 2 hrs. Esp good for COPD or hypercarbic resp distress
  3. Extubate to Bipap. This gives a little extra PEEP so also good for COPD.