Monthly Archives: October 2012

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Jehovah’s Witnesses And Blood Transfusion Demystified

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Injury can be a bloody business, and trauma professionals take replacement of blood products for granted. Some patients object to this practice on religious grounds, and their health care providers often have a hard time understanding this. So why would someone refuse blood when the trauma team is convinced that it is the only thing that may save their life?

Jehovah’s Witnesses are the most common group encounted in the US that refuse transfusion. There are more than 20 million Witnesses worldwide, with over 7 million actively preaching. It is a Christian denomination that originated in Pennsylvania during the 1870s.

Witnesses beleive that the bible prohibits taking any blood products, including red cells, white cells, platelets or plasma. It also includes the use of any dialysis or pump equipment that must be primed with blood. This is based on the belief that life is a gift from God and that it should not be sustained by receiving blood products. The status of certain prepared fractions such as albumin, factor concentrates, blood substitutes derived from hemoglobin, and albumin is not clear, and the majority of Witnesses will accept these products. Cell saver techniques may be acceptable if the shed blood is not stored but is immediately reinfused.

Why are Witnesses so adamant about refusing blood products? If a transfusion is accepted, that person has abandoned the basic doctrines of the religion, and essentially separates themselves from it. They may then be shunned by other believers.

So what can trauma professionals do to provide best care while abiding by our patient’s religious belief? In trauma care it gets tricky, because time is not on our side and non-blood products are not necessarily effective or available. Here are some tips:

  • Your first duty is to your patient. Provide the best, state of the art care you can until it is absolutely confirmed that they do not wish to receive blood products. In they are comatose, you must use blood if indicated until the patient has been definitively identified by a relative who can confirm their wishes with regard to blood. Mistaken identity does occur on occasion when there are multiple casualties, and withholding blood by mistake is a catastrophe.
  • Talk with the patient or their family. Find out exactly what they believe and what they will allow. And stick to it.
  • Aggressively reduce blood loss in the ED. We are not always as fastidious as we should be because of the universal availabilty of blood products. Use direct pressure or direct suture ligation for external bleeding. Splint to reduce fracture bleeding.
  • Aggressively use damage control surgery. Don’t go for a definitive laparotomy which may take hours. Pack well, close and re-establish normal physiology before doing all the final repairs.
  • Always watch the temperature. Pull out all the stops in terms of warming equipment. Keep the OR hot. Cover every bit of the patient possible with warming blankets. All fluids should be hot. Even the ventilator gases can be heated.
  • Think about inorganic and recombinant products such as Factor VIIa, tranexamic acid and Vitamin K. These are generally acceptable.
  • Consider angiography if appropriate, and call them early so their are no delays between ED and angio suite or OR and angio suite.

Bottom line: Do what is right for your patient. Once you are aware of their beliefs, avoid the use of any prohibited products. Speak with them and their family to clarify exactly what you can and cannot do. This is essentially an informed consent discussion, so make sure they understand the consequences. Follow their wishes to the letter, and don’t let your own beliefs interfere with what they want.

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Retained Hemothorax And Empyema

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Patients with chest trauma sustain hemothorax on occasion. The trauma professional usually picks this diagnosis up in the initial evaluation and makes a decision whether or not to drain it. The parameters for this decision are not very clear, even today. But what happens when there is residual hemothorax? Should we be more aggressive in getting it out?

All this boils down to an understanding of the natural history of retained hemothorax. This kind of information can help us decide whether to be more aggressive in our efforts to remove it. The results of a multicenter study looking at this issue was published recently. They focused on patients who had a chest tube placed for management of either hemo- or pneumothorax within 24 hours of admission. Patients who had suspected retained hemothorax after tube removal received a CT scan within 14 days. The usual outcomes were studied (length of stay, complications) as well as development of empyema (purulence, acidic pleural fluid, positive Gram stain or culture).

Some interesting results:

  • 328 patients were enrolled across 20 centers. Not a lot, but one of the bigger studies to date.
  • Empyema was diagnosed in 27% of patients
  • Risk factors identified included rib fractures, ISS > 25, and performance of additional interventions for drainage
  • Patients who developed empyema stayed in the ICU and the hospital longer

Bottom line: Retained hemothorax turns into a very serious problem in a quarter of trauma patients who have a chest tube inserted. The presence of residual blood after the chest tube is removed should prompt us to figure out if it’s solid clot or liquid blood (remember the old decubitus view chest xray? They still work!). If it’s liquid, consider drainage via thoracentesis or a smaller catheter. If it’s clot, it may require more invasive techniques to drain it (VATS). If you decide to send the patient home, have them watch out for fevers, chest pain, dyspnea and other symptoms and signs of a developing complication, and make sure they report it to you promptly.

Related post:

Reference: Development of posttraumatic empyema in patients with retained hemothorax: Results of a prospective, observational AAST study. J Trauma 73(3):752-757, 2012.

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When to Give Spleen Vaccines After Splenectomy for Trauma

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I’ve written previously on the (f)utility of giving vaccines after splenectomy for trauma (click here to read). However, it is more or less a medicolegal standard, so pretty much everyone gives them. The big question is, when? 

Some centers give them immediately postop, some before hospital discharge, and some during their postop visit. Who is right? The argument is that major surgery produces some degree of immunocompromise. So if the vaccines are given too early, perhaps the anitbodies will not be processed as effectively, and the response to an actual bacterial challenge might not be as good.

One prospective study randomized patients to receive their pneumococcal vaccine either 1, 7, or 14 days after surgery. IgG levels were measured before vaccination and again after 4 weeks. This study found that antibody concentrations were the same in all groups. However, functional activity of the antibodies was low in the 1 and 7 day groups, and nearly normal in the 14 day group.

Following this, a rat study looked at vaccination timing followed by exposure to pneumococcus. These animals were splenectomized, then given a real or sham vaccination at 1, 7, or 42 days. They then had pneumococcus injected into their peritoneal cavity. About 70% of all rats with sham vaccination died. Only 1.5% of the vaccinated rats died, and there were no differences based on vaccination timing.

Bottom line: Neither antibody titer studies nor rat studies easily translate into recommendations for treating overwhelming post-splenectomy sepsis (OPSS) in humans. And such a study can never be done because of the rarity of this condition (less than 70 cases since the beginning of time). It really boils down to your specific population, balancing your assurance that your patient will get it against the possibility that their immune system may not react to it as much as it could. 

At our center, we give the vaccines as soon as possible postoperatively. This ensures that it is given, and erases any doubt of what might happen if the patient does not show up for their postop check.

References:

  • Immune responses of splenectomized trauma patietns to the 23-valent pneumococcal polysaccharide vaccine at 1 versus 7 versus 14 days after splenectomy. J Trauma 44(5):760-766, 1998.
  • Timing of vaccination does not affect antibody response or survival after pneumococcal challenge in splenectomized rats. J Trauma 45(4):682-697, 1998.

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Wounds: When Are They Too Old To Close?

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At some point in their training, every trauma professional is taught that there is a certain period time during which a wound can be safely closed. The exact number varies, but is usually somewhere between 6 and 24 hours. After that, we are told, “bad things happen.”

Always question dogma, I say. Is this true, or is it another one of those “facts” that have been propagated through the ages? Two emergency medicine groups recently performed a meta-analysis to try to answer my question. As usual, they found that much of the published literature is not very good. Out of 418 papers in their original search, only 4 fully met their criteria (laceration repaired primarily, in the ED, with clear early vs delayed criteria.

With the exception of one study with a very limited focus, there was no correlation between wound age and infection or dehiscence after primary closure. None of the studies could reliably provide a specific time beyond which closure was destined to fail. And the use of antibiotics in some of the studies also confounded the results.

Bottom line: It is more likely that infection-prone wounds get infected, not old ones. Although leaving a wound open to heal by secondary intention usually avoids the problem, it’s a big patient dissatisfier, especially with large wounds. Since many patients don’t present to the ED until their wound is “old”, it may be reasonable to try primary closure in all but infection-prone wounds. (The meaning of that phrase is not exactly clear, but most of us know it when we see it.) 

Reference: The impact of wound age on the infection rate of simple lacerations repaired in the emergency department. Injury 43(11):1793-1798, 2012.