Laryngospasm and Hypoxia after Ketamine

Posted by Patrick Lickiss on Feb 22, 2012 in General, Research, Treatment | 0 comments

There has been some talk recently about wanting to include ketamine in the pharmacopea for EMS providers. An interesting case study was published recently looking at a potential complication of providing ketamine for sedation:

Laryngospasm and Hypoxia after Intramuscular Administration of Ketamine to a Patient in Excited Delirium.
Prehosp Emerg Care. 2012 Jan 17;

Authors: Burnett AM, Watters BJ, Barringer KW, Griffith KR, Frascone RJ

ABSTRACT: An advanced life support emergency medical services (EMS) unit was dispatched with law enforcement to a report of a male patient with a possible overdose and psychiatric emergency. Police restrained the patient and cleared EMS into the scene. The patient was identified as having excited delirium, and ketamine was administered intramuscularly. Sedation was achieved and the patient was transported to the closest hospital. While in the emergency department, the patient developed laryngospasm and hypoxia. The airway obstruction was overcome with bag-valve-mask ventilation. Several minutes later, a second episode of laryngospasm occurred, which again responded to positive-pressure ventilation. At this point the airway was secured with an endotracheal tube. The patient was uneventfully extubated several hours later. This is the first report of laryngospam and hypoxia associated with prehospital administration of intramuscular ketamine to a patient with excited delirium.

Now I don’t know a whole lot about the pharmacodynamic of ketamine, is this something we need to worry about?  Is this an expected side effect in a portion of the population?  Is this simply an abbarency?  Has your system looked at alternate sedatives like ketamine? Let me know!

Adequacy of Pain Management in Children with Long Bone Fractures

Posted by Patrick Lickiss on Feb 15, 2012 in General, Research, Treatment | 6 comments

Continuing last week’s theme of trauma related research, today’s study is from the journal Pediatric Emergency Care and looks at emergency room management of pain in pediatric patients suffering from isolated long bone fractures. The researchers underwent a retrospective study to determine if patients ages 0-15 years were given adequate dosing based on standard, inadequate dosing or no pain medication at all when they presented with single long-bone fracture.

Here’s the abstract:

Pediatr Emerg Care. 2012 Jan 20. [Epub ahead of print]

Analgesic Administration in the Emergency Department for Children Requiring Hospitalization for Long-Bone Fracture.

Dong L, Donaldson A, Metzger R, Keenan H.

From the *Intensive Medicine Clincal Program, Intermountain Healthcare; †Department of Pediatrics, University of Utah; ‡Division of Pediatric Surgery, University of Utah School of Medicine, Primary Children’s Medical Center; and §Department of Pediatrics, University of Utah, Salt Lake City, UT.

OBJECTIVES: The objective of the study was to describe analgesia utilization before and during the emergency department (ED) visit and assess factors associated with analgesia use in pediatric patients with isolated long-bone fractures.

METHODS: This retrospective cohort study of patients aged 0 to 15 years with a diagnosis of an isolated long-bone fracture was conducted at a single, level I pediatric trauma center. Patients included were treated in the ED within 12 hours of injury and subsequently admitted to the hospital from January 2005 through August 2007. Pain medication received within the first hour after ED arrival was categorized based on prespecified standard doses as follows: adequate, inadequate, and no pain medication received. Cumulative logistic regression analysis assessed factors associated with analgesia use.

RESULTS: There were 773 patients with isolated long-bone fracture included in the analysis. Overall, 10% of patients received adequate pain medicine; 31% received inadequate medicine; and 59% received no pain medicine within 1 hour of ED arrival. In multivariable analysis, children with younger age, longer time from injury to ED arrival, closed fractures, and upper-extremity fractures were less likely to receive adequate pain medicine during the ED visit. Of those transported by emergency medical services directly from the scene to the ED, 9 (10%) of 88 were given pain medication during transport.

CONCLUSIONS: Pain management in pediatric patients following a traumatic injury has been recognized as an important component of care. This study suggests that alleviation of pain after traumatic injury requires further attention in both the prehospital and ED settings, especially among the youngest children.

A few interesting items jump out  when reviewing this study.  First, only 10% of patients were treated with adequate amounts of analgesia.  Second, 59% of patients received no pain management within the first hour of arriving.  Just to review, that’s 59% of patient 15 years and younger with long bone fractures receiving no pain medication whatsoever.  Finally, only 10% of patients arriving via EMS were given any pain medication at all.  There was no analysis performed on the adequacy of EMS dosing.  To review, that means that EMS did not give pain medication to 90% of pediatric patient with long bone fractures.  In short, this is unacceptable.

The researchers looked at root cause and found the expected variables: younger age, upper extremity fractures and closed fractures resulted in lower quantities of pain medication.  The EMS-related finding, however, is what upsets me the most about this paper.  If my son breaks an arm or a leg, the paramedics had better intend on giving him pain medication.  Same with the ED staff.

So what about you?  Do you treat pediatric patients as aggressively for pain as you do adults?  What about your co-workers?  What are some of the things that keep you from treating pediatrics aggressively?  Let me know in the comments.

Are Prehospital Trauma Triage Criteria Effective?

Posted by Patrick Lickiss on Feb 8, 2012 in Assessment, General, Research, Treatment | 0 comments

Chances are, the system you work in has a list of trauma criteria. Patients meeting such criteria are transported to specific trauma hospitals where advanced services are available. Some systems present their trauma criteria as guidelines while others are set in stone. Some systems mandate that certain criteria be activated while others are left to the discretion of the paramedics. The real question is: do these criteria even work?

Before answering that question, we need to decide what makes up an effective trauma triage system. In my opinion, an effective trauma system doesn’t miss severe life-threatening injuries and exhibits a minimum level of over-triage.
Why not just activate every trauma patient regardless of severity? A more thorough assessment is better right?

Yes and no. Well, actually no. Thorough assessment is good, unnecessary assessment isn’t.  Think about what happens when you bring in a trauma patient. Depending on the hospital there are up to 15 or so people in the room or immediately on stand-by. This includes physicians, nurses, lab technicians, radiology technicians, respiratory therapists, social workers (my favorite!) and many more. When dedicated to your patient, at least initially, they are unavailable to respond to another patient.

Now think about what happens to your patient: labs, x-rays, CT scans and countless other diagnostics. Each time a vein is punctured, there is a risk of infection. Every x-ray and CT scan involves exposing your patient to radiation which has additive effects over time.  In the end, a trauma system should be judged both on catching serious injuries and not activating patients unnecessarily.

Imagine my pleasure at reading the following excerpt from an Australian study published last year in Injury:

Injury. 2011 Sep;42(9):889-95. Epub 2010 Apr 28.

Differentiation of confirmed major trauma patients and potential major trauma patients using pre-hospital trauma triage criteria.

Cox S, Smith K, Currell A, Harriss L, Barger B, Cameron P.

Strategy & Planning Department, Ambulance Victoria, Australia. Shelley.Cox@ambulance.vic.gov.au

BACKGROUND: There is a paucity of literature comparing trauma patients who meet pre-hospital trauma triage guidelines (‘potential major trauma’) with trauma patients who are identified as ‘confirmed major trauma patients’ at hospital discharge. This type of epidemiological surveillance is critical to continuous performance monitoring of mature trauma care systems. The current study aimed to determine if the current trauma triage criteria resulted in under/over-triage and whether the triage criteria were being adhered to.

METHODS: For a 12-month time period there were 45,332 adult (≥16 years of age) trauma patients transported by ambulance to hospitals in metropolitan Melbourne. This retrospective study analysed data from 1166 patients identified at hospital discharge as ‘confirmed major trauma patients’ and 16,479 patients captured by the current pre-hospital trauma triage criteria, who did not go on to meet the definition of confirmed major trauma. These patients comprise the ‘potential major trauma’ group. Non-major trauma patients (N=27,687) were excluded from the study. Pre-hospital data was sourced from the Victorian Ambulance Clinical Information System (VACIS) and hospital data was sourced from the Victorian State Trauma Registry (VSTR). Statistical analyses compared the characteristics of confirmed major trauma and potential major trauma patients according to the current trauma triage criteria.

RESULTS: The leading causes of confirmed major trauma and potential major trauma were motor vehicle collisions (30.1% vs. 19.2%) and falls (30.0% vs. 48.7%). More than 80% of confirmed major trauma and 24.4% of potential major trauma patients were directly transported to a major trauma service. Overall, similar numbers of confirmed major trauma patients and potential major trauma patients had one or more aberrant vital signs (67.0% vs. 66.4%). Specific injuries meeting triage criteria were sustained by 69.2% of confirmed major trauma patients and 51.4% of potential major trauma patients, while 11.7% of confirmed major trauma patients and 4.6% of potential major trauma patients met the combined mechanism of injury criteria.

CONCLUSIONS: While the sensitivity of the current pre-hospital trauma triage criteria is high, if paramedics strictly followed the criteria there would be significant over-triage. Triage models using different mechanistic and physiologic criteria should be evaluated.

There are a few reasons I like this study, not the least of which is that the following ad campaign came out of Australia:

But I digress.  Basically, I think this study takes a pretty realistic look at what works and what doesn’t in their system.  According to the study authors, their triage criteria (and associated paramedic discretion) catch about 80% of confirmed traumas.  This is respectable sensitivity (ability to identify positive results).  The authors admit, however, that strict adherence to triage criteria would result in unacceptably high over-triage.

With no evidence to back this up, my gut reaction is that most trauma systems suffer from similar over triage, or at least the potential for over triage.

What about your system?  Have you done anything to reduce the amount of over triage for trauma patients?  Are the study authors totally off base?  Let me know in the comments.

Early Increase in Blood Glucose Predicts Poor Outcome

Posted by Patrick Lickiss on Feb 1, 2012 in General, Research, Treatment | 1 comment

In a study just electronically published in Diabetes Care, researchers explore the link, if any, between changes in blood glucose level following return of circulation in patients initially presenting in ventricular fibrillation and ultimate patient outcome.

Take a quick look at the abstract:

Early Increase in Blood Glucose in Patients Resuscitated From Out-of-Hospital Ventricular Fibrillation Predicts Poor Outcome.

Nurmi J, Boyd J, Anttalainen N, Westerbacka J, Kuisma M.

Helsinki Emergency Medical Services, Department of Anesthesia and Intensive Care, Helsinki University Central Hospital, Helsinki, Finland.

OBJECTIVE: To describe the trend of blood glucose immediately after successful resuscitation from out-of-hospital ventricular fibrillation.
RESEARCH DESIGN AND METHODS: Data from cardiac arrest registry supplemented with blood glucose data were analyzed in this population-based observational study. Between 2005 and 2009, a total of 170 adult patients survived to hospital admission after resuscitation from bystander-witnessed cardiac arrest of cardiac origin and ventricular fibrillation as an initial rhythm.
RESULTS: Sufficient data for analysis were available in 134 (79%) patients, of whom 87 (65% [95% CI 57-73]) survived to hospital discharge in Cerebral Performance Category 1 or 2. Blood glucose did not change significantly between prehospital (10.5 ± 4.1 mmol/L) and admission (10.0 ± 3.7 mmol/L) in survivors (P = 0.3483), whereas in nonsurvivors, blood glucose increased from 11.8 ± 4.6 to 13.8 ± 3.3 mmol/L (P = 0.0025).
CONCLUSIONS: Patients who are resuscitated from out-of-hospital ventricular fibrillation, but whose outcome is unfavorable are characterized by significant increase of blood glucose in the ultraacute postresuscitation phase.

WHAT’S IT ALL MEAN?
The first limitation of any study reporting observations from paramedic charts is that the data comes from paramedic charts.  We, as an industry, are notorious for estimating and rounding.  Is a systolic blood pressure 136 or 140?  Does it make a difference?  Sometimes it does, especially when comparing prehospital to in-patient values.  That being said, blood glucose is probably pretty reliably documented because it is easy to pull up the last value on many glucometers.

The second limitation is a frequency of glucometer calibration.  I know EMS systems which dictate that this be done daily and some which never calibrate.  That being said, this study did look for significant changes in blood glucose so my hope would be that they were able to overcome some of those variances.

The third limitation is that they rely on EMS performing a blood glucose on a post arrest patient.  Should this be done routinely?  Probably.  Is it?  Maybe, but who knows.  This limitation may have kept the study population artificially low.

There are a few things I like about this study.  First of all, they focus on V-fib presenting patients with witnessed cardiac arrest.  This is the population which appears to have the best shot at getting out of the hospital alive.

Second, they look only at patients who survived to hospital admission and their metric for “good outcome” is neurologically intact after discharge.  It’s high time that we focused more studies are what actually matters (getting patients out of the hospital alive and functioning) and ignoring what doesn’t (ROSC).

RESULTS
The researchers found that a significant increase in blood glucose from the prehospital setting to the in-patient one is linked to poor outcomes.  It should be noted that this is probably not a causal relationship.  Will this change prehospital care?  Probably not.  Thought if, as a Critical Care provider, you are transferring a post arrest patient and note an increase in blood glucose since the resuscitation in the field it might be wise to expect a re-arrest.

Does your system routinely check blood glucose on post arrest patients?  Do you know how to recall the last reading on your glucometer?  Let me know in the comments.

Reflections on a New System

Posted by Patrick Lickiss on Jan 25, 2012 in Current Events, EMS 2.0, General | 0 comments

So I’ve been working in my new EMS system for a little while now and a few readers have asked if I have noticed any differences between Western Michigan and Alameda County. I’ll spare you the weather-related differences and focus on the actual EMS aspect.

DISPATCH
The three counties we serve have fully embraced the Medical Priority Dispatch System (MPDS). While cards are used to determine if a call is Alpha (stubbed toe) through Echo (cardiac arrest) in severity, each county medical director has assigned a response priority to the phone triage results. A Priority One call involves both the transport and first responder units traveling with lights and sirens. A Priority Two call involves just the first responders using lights and sirens and a Priority Three call involves just the transporting unit responding with no first responders.

The end result of this system is fewer units running code around the city. The risk, of course, is undertriage. I can say that, so far, I have only been upgraded en route a handful of times and have not yet gone to a Priority Three that needed more medical resources (just the occasional manpower call out for lifting). There is a QA/QI process at the dispatch level and though I was skeptical at first, the system seems to work. I’m even considering cross training in dispatch after I get my bearings (I know, I know!).

FIRST RESPONDERS
All of the fire departments we routinely run with are BLS, at the most. Many of the volunteer agencies require only Medical First Responder. Now this is not to say that there aren’t some paramedics who volunteer with these agencies, but they are generally limited to providing BLS care. There is a caveat, however. If I, as the transporting medic, know that a volunteer firefighter is an approved paramedic in the county, I can ask him/her to operate at the ALS level. Medical direction basically offers us a way to have additional ALS hands on scene and during transport as needed. Pretty cool if you ask me.

The Sheriff’s Department in our neighboring county also staffs first response paramedic units. Back when the Federal government was first handing out money to develop EMS systems, this county chose to funnel those funds to law enforcement rather than fire. Today, the ALS first responder program is limited to a few townships under a contract basis with the Sheriff’s office, but the idea is sound and generally works well. When thinking about redesigning a system from the ground up, looking to this type of first response may be helpful.

PROTOCOLS
Now down to the nitty gritty: the medicine.

The protocols here are largely the same though we have a few medications like fentanyl and magnesium sulfate that I didn’t carry in Alameda. Most treatments are performed based on standing orders, though there are a few which I take issue with. For instance, I have to call medical control to treat abdominal pain. I can give pain meds for traumatic injuries, but any non-traumatic pain requires a physician consult. Now, that being said, I haven’t been turned down yet, but it feels a bit old-school to have to ask. That being said, the new Michigan State protocols allow aggressive treatment of anaphylaxis with IM/IV epinephrine and encourage liberal use of CPAP. I feel as though I’ve been able to treat critical patients as I see fit without needing to interact with medical control too often. That seems like a good fit to me.

Perhaps the best part about our protocols is that they are interpreted as guidelines, not as a cookbook. Decisions made in the best interest of the patient are honored as such.  That is a similarity to Alameda County that I am thankful to see.

CALL VOLUME
In a word: busy. I would say that, on a given shift, I run the same number of 911 calls that I did in Alameda. We also run transfers on top of that. The upside is that our days go by quickly. The downside is that I’m exhausted at the end of a shift. I will say, I actually enjoy running transfers from time to time. It’s usually a slower pace, but we also run CCT calls (including written orders from the sending physician with whatever medications they need us to carry) so some of the transfers are pretty critical.

SO WHAT’S IT ALL MEAN
Professionally, I miss Alameda County like crazy. That being said, the system here feels very similar. The protocols are largely the same and the Medical Director seems to support the idea of paramedics as true medical providers. The receiving facilities here are great and welcome us as team members. Though I miss where I started, I’m excited about where I am and where I’m going. Thanks for indulging me in a self-centered post!

Have you moved to a vastly different EMS system than where you started?  Any reflections on that process?  What do you like better about your system now?  What about your old system?  Let me know in the comments!

Image via Flickr