Tag Archives: EMS

Bystander CPR For People Not In Cardiac Arrest

CPR has increased the survival rate of patients suffering cardiac arrest, and early bystander CPR has been shown to double or triple survival. The sad truth is that CPR is not frequently performed by the general public. The American Heart Association has attempted to simplify CPR to the point that even untrained bystanders can administer chest compressions without a pulse check and without rescue breathing.

Bystander CPR

But what happens if that well-intentioned bystander starts CPR in someone who has not arrested? How often does this happen? Can the patient be injured?

The Medical College of Wisconsin reviewed the charts of all patients who received bystander CPR in Milwaukee County over a six year period. There were 672 incidents of bystander CPR. Of those cases, 77 (12%) were not in arrest when assessed by EMS personnel, and the researchers focused on those patients.

EMS response time averaged 5 minutes, and was greater than 10 minutes in only 2 cases. Average patient age was 43(!). The male/female ratio was just about 50:50, and the majority of the incidents took place in the home or residence.

Hospital records were available for further analysis in 72 of the patients. A quarter were sent home, a quarter admitted to a ward bed, and half were admitted to an ICU. Only 12 (17%) had a cardiac-related discharge diagnosis. The next most common discharge diagnoses were near-drowning, respiratory failure and drug overdose. Younger patients (<19) were usually near-drowning victims, and older patients (>54) were most commonly diagnosed with syncope. Five patients did not survive. Only one CPR injury was identified, which was charted as rhabdomyolysis “secondary to having received CPR” (a weak injury diagnosis, in my opinion).

Bottom line: The potential benefit of bystander CPR outweighs the risk of injury or performing it on a victim who is not in arrest. This study shows that, although these patients may not need CPR, they are generally very ill. Given the rapid EMS response times and the younger average age of the victims, no real injuries occurred. The new American Heart Association recommendations are beneficial and should be distributed widely.

Reference: The frequency and consequences of cardiopulmonary resuscitation performed by bystanders on patients who are not in cardiac arrest. Prehosp Emerg Care 15:282-287, 2011.

AAST 2011: Patients Evaluated But Not Transported By EMS

Injured patients transported to the ED are just the tip of the iceberg. There are some patients who are evaluated by EMS, either at the scene or in their home, but never transported. These patients do not appear in any trauma registry and little information is known about how they do after their evaluation.

Stanford University reviewed county data and found 5,865 patients out of 69,000 who were evaluated by EMS but not transported (3 counties, 3 years of data). Over a quarter (29%) presented to an ED later and 92 were admitted (2% of the total). By linking available vital statistics data, at least 7 were found to have died.

Bottom line: Patients who are evaluated by EMS but ultimately not transported to a hospital may have unsuspected problems. The mortality is very low (0.14%) but these may represent preventable deaths. It is not practical to force everyone to go to the ED. However, it should be cost-effective to at least make a followup call the next day on these select patients to see if they should be urged to get further evaluation in the ED.

Reference: The forgotten trauma patient: outcomes for injured patients evaluated by EMS but not transported. AAST 2011 Annual Meeting, Oral Paper 46.

Is The Glasgow Coma Scale (GCS) Getting Too Old?

Traumatic brain injury (TBI) is one of the leading causes of death from trauma worldwide. The assessment of TBI was revolutionized in 1976 when the GCS scale was first introduced. Shortly after its introduction, it was found to be predictive of outcome after brain injury. But it does have some drawbacks: it is somewhat complicated, and interrater reliability is low.

Interestingly, a number of studies have shown that the motor component of GCS is nearly as accurate as the full score in predicting survival. Thus, the Simplified Motor Score (SMS) was introduced as a possible substitute for the GCS in 2007. It was found to be equivalent for predicting survival when applied in the ED.

SMS scoring:

  • Obeys commands = 2
  • Localizes pain = 1
  • Withdraws (or less) to pain = 0

So can this scale be validated in the field when applied by prehospital providers?

Nearly 10 years of data (almost 20,000 patients) from the Denver Health trauma registry was analyzed to attempt to validate SMS when used by EMS. Although the statistics were not perfect, they found that GCS and SMS were equivalent for predicting the presence of a brain injury, need for emergency intubation, need for neurosurgical intervention, and death. Interestingly, they found that both SMS and GCS were not quite as good at predicting overall outcomes as previously thought.

Bottom line: The simplified motor score is a simple system that has now been shown to be as accurate as GCS in predicting severity and outcome from head injury. To be clear, though, neither is a perfect system. They must still be combined with clinical and radiographic assessments to achieve the best accuracy. But SMS can and should be used both in-hospital and prehospital to get a quick assessment, and may help determine early intervention and need for activating the trauma team.

References:

  • Assessment of coma and impaired consciousness: a practical scale. Lancet 2:81-84, 1976.
  • Assessment and prognosis of coma after head injury. Acta Neurochir (Wien) 34:45-55, 1976.
  • Validation of the simplified motor score in the out-of-hospital setting for the prediction of outcomes after traumatic brain injury. Ann Emerg Med, in press, Aug 2011.

Hare Traction – Putting It On, Taking It Off

Femoral traction devices have been around for a long time. One reader has asked about the timing of removal of these devices after they arrive at the hospital. I learned a number of things while reviewing the literature to answer this question.

Most importantly, there is really only one indication for applying a traction splint to the femur: an isolated, relatively mid-shaft femur fracture. Unfortunately, there are lots of contraindications. They consist of other injuries or fractures that could sustain further damage from traction. Specifically, these include:

  • Pelvic or hip fracture
  • Hip dislocation
  • Knee injury
  • Tib/fib, ankle or foot fracture

I did find one interesting study from 1999 that looked at how useful these splints really were. Of 4,513 EMS runs, only 16 had mid-thigh trauma and 5 of these appeared to have a femur fracture. Splint application was attempted in 3, and only 2 were successful. This was the experience in only one city (Evanston, IL) for one year. However, it mirrors what I see coming into our trauma center.

Unfortunately, when it comes to removal, there are very few guidelines out there. My advice is to have your orthopedic surgeon evaluate as soon as imaging is complete. They can help decide whether converting to some type of definitive traction is necessary, or whether it can be changed to a more conventional splint. In any case, the objective is to minimize the total amount of time in the traction splint to avoid any further injury to other structures.

Reference: Prehospital midthigh rauma and traction splint use: recommendations for treatment protocols. Am J Emerg Med, 19:137-140, 2001.

    Helicopter Transport of Trauma Patients Saves Lives

    Helicopter EMS (HEMS) transport of trauma patients is used primarily to decrease the amount of time between injury and arrival at the trauma center. Unfortunately, efficacy studies have provided conflicting answers as to whether this is actually true. Last year, the CDC completed a large sample study of this issue using the National Trauma Data Bank (NTDB) in an attempt to determine if HEMS flights are effective.

    Using almost 150,000 entries in the NTDB for 2007, they were able to isolate over 56,000 adult records with complete data points. They looked for mortality patterns based on age, injury severity, and revised trauma score, comparing patients who were transported by air vs ground.

    They found the following:

    • Odds of dying in-hospital were 39% lower overall when transported by helicopter
    • This survival advantaged disappeared for patients age 55 and older, possibly because of decreased reserve, comorbidities, more complications, or medications that interfere with successful resuscitation
    • Regardless of type of transport, males always fared worse than females

    Bottom line: This is a large and intriguing study. About 85% of the US population has access to a Level I or II trauma center within an hour. However, a third of those can only get there in that period of time if transported by air. This mode of transport has a significantly lower mortality rate. However, there are cost and safety considerations as well. The key now is to figure out which patients will have the best outcomes after air transport. This will require more work, looking at more than just mortality (e.g. disability, complications).

    Reference: Reduced mortality in injured adults transported by helicopter emergency medical services. Prehospital Emerg Care 15(3):295-302, 2011.