Autotransfusing blood that has been shed from the chest tube is an easy way to resuscitate trauma patients with significant hemorrhage from the chest. Plus, it’s usually not contaminated from bowel injury and it doesn’t need any fancy equipment to prepare it for infusion.
It looks like fresh whole blood in the collection system. But is it? A prospective study of 22 patients was carried out to answer this question. A blood sample from the collection system of trauma patients with more than 50 cc of blood loss in 4 hours was analyzed for hematology, electrolyte and coagulation profiles.
The authors found that:
- The hemoglobin and hematocrit from the chest tube were lower than venous blood (Hgb by about 2 grams, Hct by 7.5%)
- Platelet count was very low in chest tube blood
- Potassium was higher (4.9 mmol/L), but not dangerously so
- INR, PTT, TT, Factor V and fibrinogen were unmeasurable
Bottom line: Although shed blood from the chest looks like whole blood, it’s missing key coagulation factors and will not clot. Reinfusing it will boost oxygen carrying capacity, but it won’t help with clotting. You may use it as part of your massive transfusion protocol, but don’t forget to give plasma and platelets according to protocol. This also explains why you don’t need to add an anticoagulant to the autotransfusion unit prior to collecting or giving the shed blood!
Related post: Chest tubes and autotransfusion
Reference: Autotransfusion of hemothorax blood in trauma patients: is it the same as fresh whole blood? Am J Surg 202(6):817-822, 2011.
It’s great when you read a study that supports your own biases. But it’s not pleasant at all when you find one that refutes what you’ve been teaching for years. Well, I found one of those and I wanted to share it with you.
I’ve always said that there are only two sizes of chest tube for trauma, big (36Fr) and bigger (40Fr). Although there was no good literature, it seemed that a large tube would help ensure drainage of bigger clots if hemothorax was present.
A multicenter observational study was carried out that looked at 353 chest tube insertions. This work monitored retained hemothorax or pneumothorax, the need for tube reinsertion or invasive procedure due to incomplete drainage, and pain during insertion.
They had roughly 50:50 large (36-40Fr) vs small (28-32Fr) tubes. Tubes inserted for hemothorax were also 50:50 for large vs small. The initial amount of blood out was small and about the same for both groups. There was no significant difference in pneumonia, retained hemothorax, or empyema. The need for an invasive procedure (VATS or thoracotomy) was about 11% in both groups. Interestingly, there was no difference in visual analog pain score between the groups either.
Basically, large tube and small tube were the same.
Bottom line: Chest tube size selection probably doesn’t matter as much as we (I?) think. So it seems to make sense to select a tube size based on your patient’s chest wall, not dogma. Although subjective pain seems to be the same as well, pain and sedation management are key because this is not a fun procedure for the patient, regardless of tube size.
Reference: Does size matter? A prospective analysis of 28–32 versus 36–40 French chest tube size in trauma. J Trauma 72(2):422-427, 2012.
I’ve written a lot about chest tubes, but there’s actually a lot to know. And a fair amount of misinformation as well. Here’s some info you need to be familiar with:
- Chest trauma generally means there is some blood in the chest. This has some bearing on which size chest tube you choose. Never assume that there is only pneumothorax based on the chest xray. Clot will plug up small tubes.
- Chest tubes for trauma only come in two sizes: big (36Fr) and bigger (40Fr). Only these large sizes have a chance in evacuating most of the clot from the pleural space. The only time you should consider a smaller tube, or a pigtail type catheter, is if you know for a fact that there is no blood in the chest. The only way to tell this is with chest CT, which you should not be getting for diagnosis of ordinary chest trauma.
- When inserting the tube, you have no control of the location the tube goes once you release the instrument used to place it. Some people believe they can direct a tube anteriorly, posteriorly, or anywhere they want. They can’t, and it’s not important (see next tip).
- Specific tube placement is not important, as long as it goes in the pleural space. Some believe that posterior placement is best for hemothorax, and anterior placement for pneumothorax. It doesn’t really matter because the laws of physics make sure that everything gets sucked out of the chest regardless of position except for things too big to fit in the tube (e.g. the lung).
- Tunneling the tube tract over a rib is not necessary in most people. In general, we have enough fat on our chest to ensure that the tract will close up immediately when the tube is pulled. A nicely placed dressing is your insurance policy.
- Adhere to an organized tube management protocol to reduce complications and the time the tube is in the chest.
And finally, amaze your friends! The French system used to size chest tubes is the diameter of the tube in millimeters times three. So a 40Fr chest tube has a diameter of 13.3mm.
There are a lot of opinions and not so much literature on how to manage chest tube air leaks. Here is some practical advice on how to deal with this occasional problem.
Most air leaks are an alveolar-pleural fistula, representing a connection between a very small airspace and the pleura. This should not be confused with a bronchopleural fistula, which involves larger airways and is much more challenging to manage.
First, identify what kind of leak it is. Remember, dry seal chest tube systems will not show an air leak unless it has a fluid chamber that can be filled with water (see related post below).
- Expiratory – occurs during normal expiration only
- Forced expiratory – occurs only with coughing
- Inspiratory – occurs during inspiration in ventilated patients
Inspiratory leaks are rare and should be managed conservatively with maneuvers to minimize airway pressures. Continuous air leaks can be monitored, but may indicate a bronchopleural fistula.
Expiratory and forced expiratory types account for about 98% of all air leaks. Small air leaks should be managed with water seal, not with increased suction. The main concept is to reduce air flow through the fistula so it can heal. A prospective study has shown that this technique stops small to moderate size leaks sooner than leaving on suction.
Larger air leaks will probably not seal on their own and are probably not safe to place on water seal. They will likely require pleurodesis, either chemical or mechanical via a VATS procedure. Blood and fibrin patches have also been tried.
Any air leak that extends hospital stay should be evaluated for appropriateness of discharge with a Heimlich valve or VATS pleurodesis.
- A prospective algorithm for the management of air leaks after pulmonary resection. Ann Thoracic Surg 66:1726-1731, 1998.
- Prospective randomized trial compares suction versus water seal for air leaks. Ann Thoracic Surg 71:1613-1617, 2001.
An air leak is a sure-fire reason to keep a chest tube in place. Fortunately, many air leaks are not from the patient’s chest, but from a plumbing problem. Here’s how to locate the leak.
To quickly localize the problem, take a sizable clamp (no mosquito clamps, please) and place it on the chest tube between the patient’s chest and the plastic connector that leads to the collection system. Watch the water seal chamber of the system as you do this. If the leak stops, it is coming from the patient or leaking in from the chest wall.
If the leak persists, clamp the soft Creech tubing between the plastic connector and the collection system itself. If the leak stops now, the connector is loose.
If it is still leaking, then the collection system is bad or has been knocked over.
Here are the remedies for each problem area:
- Patient – Take the dressing down and look at the skin entry site. Does it gape, or is their obvious air hissing and entering the chest? If so, plug it with petrolatum gauze. If not, the air is actually coming out of your patient and you must wait it out.
- Connector – Secure it with Ty-Rap fasteners or tape (see picture). This is a common problem area.
- Collection system – The one-way valve system is not functioning, or the system has been knocked over. Click here for an example. Replace it immediately.
Note: If you are using a “dry seal” system (click here for more on this) you will not be able to tell if you have a leak until you fill the seal chamber with some water.