All posts by The Trauma Pro

Is Daily Enoxaparin Dosing As Good As Twice Daily?

Venous thromboembolism (VTE) remains a big problem for trauma professionals and the patients they take care of.  Every trauma center has some sort of VTE prophylaxis protocol for stratifying risk, prescribing mechanical or pharmacologic prophylaxis, and monitoring effectiveness.

This is all well and good for patients in the hospital. But what happens once they go home?  Who needs to continue chemoprophylaxis? For how long? And what product? These are all tough questions, and are not usually part of the protocol. It is an important issue, and I’d like to address the last question in this post.

Typically, patients who need ongoing chemical prophylaxis after trauma are sent home on a low molecular weight heparin product. This is usually enoxaparin. As you know, this drug has two possible dosing regimens for prophylaxis: 30 mg subq twice a day or 40 mg subq once a day.

Now, nobody likes to give themselves a shot, ever. But if one has the choice between once a day vs twice, I think it’s safe to say everyone would pick the single dose. But it just doesn’t seem right that 60 mg spread out over two doses is just as effective as 40 mg once a day. Unless, of course, we are radically overdosing on the twice a day regimen.

So is the one-a-day regimen as good as twice a day? There is older support in the orthopedic surgery literature that it is. However, general trauma patients are probably at higher risk than those old studies would suggest. The trauma group in Gainesville FL looked at this question. They had been using the once a day dose for years, then changed to twice daily administration. They performed a retrospective study of their experience.

Here are the factoids:

  • The authors excluded the extremes of injury: patients admitted for < 2 days, or death within 2 days
  • There were 409 patients in the once daily group and 278 patients with twice daily dosing
  • About 3% of patients with once daily dosing developed VTE vs only 1% in the twice daily group
  • Bleeding complications occurred in 1.8% of the once daily group vs 2.7% in the twice daily group
  • Neither of these results was statistically significantly different

Bottom line: Although the authors try to imply that twice daily dosing “may be more effective” than once daily, they do admit that the statistics don’t show that. Unfortunately, the study design makes it nearly impossible to derive any firm results. It is a retrospective study designed long after the actual patient care, and does not take into account anything other than rudimentary risk stratification. 

My take on the topic is that it is unlikely that once daily dosing is as good as twice daily. Unfortunately, we just don’t have any literature to support that yet. Until we do, I recommend that you take a close look at your individual patient’s risk for VTE, and err on the side of giving enoxaparin twice daily until we know better.

Reference: Once- Versus Twice-Daily Enoxaparin for Venous Thromboembolism Prophylaxis in High-Risk Trauma Patients. J Intensive Care Med 26(2):111-115, 2011.

When Should You Activate Your Backup Trauma Surgeon?

The American College of Surgeons requires all US Trauma Centers to publish a call schedule that includes a backup trauma surgeon. This is important for several reasons:

  • It maintains a high level of care when the on-call surgeon is encumbered with multiple critical patients, or has other on-call responsibilities such as acute care surgery
  • It reduces the need to place the entire trauma center on divert due to surgeon issues

However, the ACS does not provide any guidance regarding the criteria for and logistics of mobilizing the backup surgeon. In my mind, the guiding principle is a simple one:

The backup should be called any time a patient is occupying the on-call surgeon’s time to the extent that they cannot manage the care of a newly arrived (or expected to arrive) patient with critical needs that only the surgeon can provide.

There’s a lot of meat in that sentence, so let’s go over it in detail. 

First, the on-call surgeon must already be busy. This means that they are actively managing one or more patients. Depending on the structure of the call system, they may be involved with trauma patients, general/acute care surgery patients, ICU patients, or a combination thereof. Busy means tied up to the point that they cannot meaningfully manage another patient.

Note that I did not say “evaluate another patient.” Frequently, it is possible to have a resident (at an appropriate training level) or advanced practice provider (APP) see the new patient while the surgeon is tied up, say in the operating room. They can report back, and the surgeon can then weigh his or her choices regarding the level of management that will be needed. Or if operating with a chief resident, it may be possible for the surgeon to briefly leave the OR to see the second patient or quickly check in on the trauma resuscitation. Remember, our emergency medicine colleagues can easily run a trauma activation and provide initial care for major trauma patients. They just can’t operate on them.

What if the surgeon is in the OR? Should they call the backup every time they are doing a case at night? Or every time a trauma activation is called while they are doing one? In my opinion, no. The chance of having a highest level trauma activation called is not that high, and as above, the surgeon, resident, or APP may be able to assess how much attention the new patient is likely to need. But recognize that the surgeon may not meet the 15 minute trauma activation attendance requirement set forth by the ACS.

However, once such a patient does arrive (or there is notification that one of these patients is on the way), call in the backup surgeon. These would include patients that are known to, or are highly suspected of needing immediate operative management. Good examples are penetrating injuries to the torso with hemodynamic problems, or those with known uncontrolled bleeding (e.g. mangled extremity).

If two or more patients are being managed by the surgeon, and they believe that they would not be able to manage another, it’s a good idea to notify the backup that they may be needed. This lets them plan their evening better to ensure rapid availability.

Finally, what is the expected time for the backup to respond and arrive at the hospital to help? There is no firm guideline, but remember, your partner and the patient are asking for your assistance! In my opinion, total time should be no more than 30 minutes. If it takes longer, then the trauma program should look at its backup structure and come up with a way to meet this time frame.

Fatigue V: Your Patients

I’ve spent the past several posts detailing how interrupted sleep interferes with the health and effectiveness of trauma professionals. But what about our patients? Being in the hospital is nothing like trying to sleep at home. The beds are terrible. There is noise in the hall. Their roommate is confused and calls out at all hours. Nurses keep coming in to check vital signs. The pulse oximeter beeps every 10 minutes.

How bad is it, really? There is no trauma patient-specific literature yet on the topic. But there is a recently published paper detailing the experience of general surgery patients admitted after elective procedures that is very revealing. The group at Dartmouth-Hitchcock Medical Center recruited adults who stayed at least one night at the hospital.

Prior to surgery, each patient completed a questionnaire that measured their baseline home sleep quality. Postop, they completed another questionnaire designed to measure their in-hospital sleep quality.  Each patient was fitted with a Fitbit Inspire HR tracker, which they wore during their entire hospitalization.  After discharge home, they completed a final outpatient sleep questionnaire.

Here are the factoids:

  • A total of 74 patients were recruited and 54 completed all phases of the study; 59 finished all of the pre-discharge phases
  • The average inpatient sleep score was 49/100, where scores less than 50 are considered substandard
  • The major culprit for in-hospital sleep disturbance was nighttime awakenings
  • Patients who had better home sleep quality tended to have a higher in-hospital score (65)
  • Sleep quality was so poor that only 40% of Fitbit devices were able to record sleep time on the first postop night, and that average time asleep was 4.7 hours
  • As expected, patients with a roommate did not sleep as well as those in private rooms
  • Average sleep time increased over subsequent nights to about 6 hours, which is still short of the recommended 7 hour minimum
  • About 88% of patients were poor sleepers preop (!), and this did not change after they returned home (85%)

Bottom line: Sleep quality in the hospital is terrible! I can vouch for this from the standpoint of being a surgeon on call, and also from one experience as a patient. There is very good data on the adverse effects of sleep loss. Fasting glucose and systolic blood pressure rise significantly after a single night of poor sleep. When these occur in a hospital, this sets the clinicians into a frenzy of prescribing sliding scale insulin or antihypertensives and other meds that are probably not needed.

There are numerous other more subtle effects as well. The best way to avoid them is to promote good sleep. But how can you do this in the hospital? Here are some tips:

  • Be aware that the way you order medications (tid vs q8hrs) has a big impact on when the evening/night doses are given. Talk to your pharmacist so your patient only gets meds when they would normally be awake and not in the middle of the night.
  • Remove unnecessary monitors that might alarm during sleep. Pulse oximeters are probably the biggest culprit. Does it need to be continuous, or can (very) occasional spot checks be done?
  • Does your patient really need vital signs taken during the middle of the night? After the first few shifts, most ward patients do not.
  • Watch out for the phlebotomists! They love to circulate early so lab results are available at the crack of dawn. Can’t it wait?
  • Some practice guidelines call for repeat scans or other studies after a certain number of hours. If one is due at 3am, can’t it wait until morning? Really?
  • On a daily basis, review all actual or potential nighttime interruptions with the patient and their nurse. Discontinue or reschedule anything that really can’t wait until morning.

Failing to provide for good sleep quality sets your patient up for complications, abnormal vitals and blood tests, and altered mental status. Do everything you can to optimize their sleep!

Reference: Deep sleep and beeps: sleep quality improvement project in general surgery patients. JACS 232(6):882-888, 2021.

Fatigue IV: Trauma Surgeons And Residents

The effects of fatigue on the surgeon have been looked at a number of times over the years. Most of this work focuses on resident physicians, however. Another problem with the majority of these studies is that they did not test the surgeon or resident on tasks that reflect real life practice.

A study from Arizona State University used a laparoscopic simulation that tested both psychomotor and cognitive skills that would be called on during real surgical procedures. In addition to the purely manual task of stacking varied sizes of rings using laparoscopic instruments, exercises were developed and validated that tested attention, tracking and other critical components. Monitored parameters included hand and tool movement, smoothness and economy of motion, and time required to complete the task. An overall proficiency score was calculated.

Five residents and nine attending physicians were tested. They were all given 4 practice sessions with the simulator before the study began. Sleep hours and caffeine use during call were recorded using a questionnaire. Each individual was then tested three times prior to being on call and three times post-call.

As would be expected, attending surgeons showed higher proficiency scores than residents both pre-call and post-call. However, both groups experienced significant declines in proficiency and significant increases in cognitive errors post-call. Interestingly, attending surgeons made 25% fewer cognitive errors post-call when compared to residents, and their psychomotor skills were unchanged. This suggests that the attendings were focused on skills at the expense of decision making.

Two other interesting items from this paper:

  • Errors increased exponentially with subjective reported fatigue in the attending surgeons. This means that a small amount of attending surgeon fatigue led to a large increase in errors. The implication is that the older attendings had less reserve, and that their greater skills and experience could be quickly overwhelmed.
  • Caffeine intake had no effect on motor skills or cognitive errors.

Bottom line: Fatigue from post-call sleep deprivation impedes psychomotor and cognitive functions, as well as performance. Residents are affected more than attending surgeons, but attending performance declines more rapidly as they grow fatigued. As any post-call surgeon knows, activities the day after call should be limited to the mundane to optimize patient safety.

In the next installment, we’ll look at the impact of poor sleep on our patients!

Reference: The effect of fatigue on cognitive and psychomotor skills of trauma residents and attending surgeons. Am J Surg 196(6):8133-820, 2008.

Fatigue III: Impact On Nurses

Although 8-hour shifts are the most common work arrangement around the country in all most occupations, they are a bit less common in nursing. Nurses have work and sleep patterns equivalent to prehospital providers. And critical care nurses probably have the most variable and punishing work patterns.

One may think that just increasing to a 12-hour shift is not that big of a deal. The nursing school at the University of Auckland performed their own survey of ICU nurses in two separate hospitals in New Zealand. They administered the Occupational Fatigue Exhaustion/Recovery Scale and evaluated differences in relation to a number of demographic variables.

Here are the factoids:

  • There were a total of 67 participants in the two hospitals and all worked 12-hour shifts.
  • Nurses at one hospital (A) worked mostly day or mostly night shifts and tended to be younger. Shifts were more mixed at the other (B).
  • About half of the nurses reported low to moderate fatigue acutely, and two thirds re-ported this level between shifts as well.
  • Factors that correlated with increased fatigue were younger age, fewer children, less years of experience, and less exercise.
  • Higher fatigue levels were reported at hospital A, which had the younger, less experienced nurses.

Bottom line: This is another survey study, but it does illustrate some common issues. Some factors could be changed by rearranging the shift structure to all day or all night shifts. Exercise was associated with less stress and could be encouraged. But the nature and pace of work in the ICU remains constant and is difficult to control for. Some strategies for positive change are listed on the next page of the newsletter.

In my next post, I’ll review the impact of sleep problems on trauma surgeons and residents.

Reference: Exploring the impact of 12-hour shifts on nurse fatigue in intensive care. Applied Nurs Res 50:151191, Dec 2019.