Archives for 2010

Without evidence of benefit, an intervention should not be presumed to be beneficial or safe.

- Rogue Medic

Asymptomatic Sustained Ventricular Fibrillation in a Patient With Left Ventricular Assist Device


ResearchBlogging.org

Also posted over at Paramedicine 101 and at Research Blogging.

Go check out the rest of the excellent material at both sites.

There’s a big difference between mostly dead and all dead. There are even other not quite dead yet categories that we tend to ignore. Asymptomatic Sustained Ventricular Fibrillation is not a group of words that appear to be appropriate together in a sentence. The old Sesame Street segment on which of these doesn’t belong would have a lot of people yelling Asymptomatic.

Sustained Ventricular Fibrillation is something we are familiar with, but in symptomatic patients – symptomatic to the point of being dead. We provide chest compressions to make up for the lack of cardiac output.

The first-generation assist devices are volume-displacement pumps. Consisting of a chamber filled passively or by suction and compressed by externally applied pressure, they provide a pulsatile flow, thereby mimicking the cyclic systole and diastole of the heart. The second generation has been developed with axial-flow, rotary-pump technology, providing a continuous blood flow.[1]

What does continuous flow mean, when assessing a patient?

No pulses, at least no pulses from the device.

On the day of admission, the patient noticed 3 consecutive discharges of the implantable cardioverter defibrillator, prompting him to call emergency medical services. On-site findings showed an alert and asymptomatic patient despite electrocardiographic analysis, exhibiting sustained ventricular fibrillation. Blood pressure measurement using a sphygmomanometer was not successful.[1]

Not an unusual 911 call. My AICD has been shocking me. My doctor told me to call 911 when that happens.

Typically, the AICD has shocked the heart back to the patient’s normal rhythm. A bit of hand holding and a discussion about possible prescriptions for a sedative and an antiarrhythmic, or an adjustment to the doses of these.

This patient is pulseless. Pulseless patients are not rare. A 911 call for a pulseless patient is usually because the pulseless patient is dead.

Contrariwise, a patient talking to me has a pulse. I have had several patients who were awake and talking, but without any palpable pulses. The absence of palpable pulses is different from the absence of pulses. All of these patients, with no palpable pulses, were significantly symptomatic.

conceivably the cardiac output had decreased substantially because of ventricular fibrillation, whereas intra-arterial monitoring revealed a continuous mean arterial pressure of 80 mm Hg (Figure 1B).[1]

respiratory rate (12 breaths/min), body temperature (36.8°C, 98.2°F), and peripheral O2 saturation (92%) were normal. Physical examination revealed a constant precardiac noise derived from the left ventricular assist device pump, whereas heart sounds were not audible. Lungs were clear and peripheral edema was not present.[1]

In other words, asymptomatic and pulseless, but with a more than adequate blood pressure and a good SpO2.

Under these circumstances, pulseless VF (Ventricular Fibrillation), the use of the term VAD (Ventricular Assist Device) is not really accurate. The VAD is working as the pump. The cardiac output is zero with VF. There is nothing to assist.

All of the blood flow is due to the VAD.

Implantable cardioverter defibrillator memory function yielded several adequate but unsuccessful electric shocks delivered in response to ventricular fibrillation, which had developed from multifocal ventricular tachycardia.[1]

Would we be more aggressive with the same presentation, if the patient were still in multiform VT (Ventricular Tachycardia)?

I think that a lot of people would, because they would want to prevent the rhythm from deteriorating to VF. Once the patient is in a rhythm that cannot get any worse, we may relax and be less aggressive.

Can this become worse?

This VF can become symptomatic. Almost all of the labs were within normal ranges. The exceptions were the electrolytes, which were low normal, or low, troponin I at 0.2 ng/mL (normal <0.03 ng/mL) and creatine kinase at 187 U/L (normal <145 U/L).

After supplementation of potassium and magnesium, amiodarone treatment was started, but first followed by 2 unsuccessful attempts of internal cardioversion. Eventually, after 3.5 hours, ventricular fibrillation could be terminated with external electrical biphasic cardioversion at 200 J, resulting in a stable rhythm with atrioventricular sequential pacing (Figure 1C). The intra-arterially determined mean blood pressure of 80 mm Hg remained unchanged.[1]

3 1/2 hours of documented asymptomatic VF.

They have this to state about the increasing use of VADs and the possible interaction/interference of VADs with AICDs (Automated Implantable Cardioverter Defibrillators).

Ventricular fibrillation is a fatal arrhythmia in the absence of circulatory support and inevitably results in death if not treated immediately. Whereas implantable cardioverter defibrillators have been proven to significantly reduce sudden cardiac death caused by ventricular tachycardia and ventricular fibrillation in severe congestive heart failure, their role in patients with left ventricular assist devices remains to be determined. 7,9 In fact, left ventricular assist devices might have a direct effect on implantable cardioverter defibrillator devices with alteration of lead parameters, ventricular tachycardias, and electromagnetic interference, thereby reducing the effectiveness of the implantable cardioverter defibrillator. 11 However, left ventricular assist devices may be able not only to support circulation but also to effectively substitute cardiac pump function in the presence of a malignant arrhythmia, even over a longer period, as previously reported with pulsatile-flow devices. 12-15[1]

Occurrence of sustained ventricular fibrillation in a patient with left ventricular assist device reflects a challenging situation that might be observed more frequently in the future: In 2008, about 4,000 left ventricular assist devices were implanted in the United States, but the numbers are expected to increase significantly. This is particularly true for the use of left ventricular assist devices in destination therapy of congestive heart failure, with the first device (HeartMate II; Thoratec Corporation) recently approved by the Food and Drug Administration for this indication.[1]

The HeartMate II LVAS includes a pump implanted inside the patient’s body and components that remain outside the patient’s body. The pump controller and batteries are worn outside the patient’s body. The system also includes a battery charger/power supply and monitor that remain outside the body..[2]

The extra equipment should be apparent, when assessing a patient with one of these devices. Smaller, less noticeable VADs may soon be available, but they will all probably have external equipment that we should notice.

Seven of the patients (all biventricular; diagnoses: four cardiomyopathy, two acute myocardial infarction, one end-stage coronary artery disease plus acute myocardial infarction) had prolonged arrhythmias that normally would have been lethal (six cases of ventricular fibrillation from 2 to 22 days, one asystole for 3 hours), but complete support of the systemic and pulmonary circulations was maintained in all seven patients with biventricular devices. Mean systemic blood flow during this period (4.6 +/- 0.6 l/min) was unchanged compared with that during sinus rhythm. Six of these patients survived to receive heart transplants.[3]

Up to 22 days of (continuous?) VF.

Blood flow during arrhythmias was not significantly different from blood flow during sinus rhythm.

It remains unclear, however, if sustained ventricular fibrillation during a longer period would have affected hemodynamics and outcome in our patient. Because left ventricular assist device patients are at high risk of developing malignant arrhythmias, which in turn can affect the cannulas’ position, effective treatment of ventricular tachycardias and ventricular fibrillation is recommended in this situation. In fact, slightly increased creatinine and troponin levels, although transient, were suggestive of some end-organ damage in our patient.[1]

Even though the patient was asymptomatic, there may have been damage occurring in the patient’s organs.

It is important to know that cardiopulmonary resuscitation (CPR) with chest compression may be performed in patients with a left ventricular assist device, if deemed clinically indicated. However, this intervention needs to be viewed cautiously because CPR may result in dislocation or damage of the cannulas or ventricle rupture, requiring emergency thoracotomy and heart surgery. CPR may be considered only in some patients who have substantial right ventricular failure, along with severe left ventricular dysfunction. Those patients may not be able to tolerate ventricular fibrillation because the right ventricle cannot deliver blood to the left side of the heart. In these cases, CPR may be necessary to prevent death while waiting for internal or external defibrillation, which can be performed without risk. Further studies are needed to determine the role of serious ventricular arrhythmias and implantable cardioverter defibrillators in patients with left ventricular assist devices.[1]

For the patient who has enough cardiac output to produce signs of life, CPR is probably a bad idea. Rapid transport to a hospital capable of treating patients with a VAD, or capable of transferring a patient with a VAD to a specialty center (just about any hospital), is probably a much better idea.

In theory, patients with sustained VF would not benefit from univentricular support because of the ineffective blood flow across the right heart associated with this dysrhythmia. In patients with refractory VT, particularly VT with a rate of less than 150 beats/min, univentricular mechanical support should be capable of sustaining adequate hemodynamics, because the right heart contributes some forward flow. Two of the most important factors affecting the physiologic flow across the pulmonary vascular bed are the status of the right ventricle and the pulmonary vascular resistance (PVR). If the PVR is elevated, whether because of VT or VF, the flow across the pulmonary vascular bed will be compromised, resulting in diminished LVAD flow. Conversely, if the PVR is low or normal, the LVAD should provide satisfactory flow. Therefore, selective agents to reduce the workload of the right ventricle and decrease the PVR, such as nitric oxide, could be useful in this setting.[4]

With a single chamber VAD, during VF, there might not be adequate blood flow. Compromised blood flow through the right ventricle might explain the elevated troponin and creatinine levels.

Footnotes:

[1] Asymptomatic sustained ventricular fibrillation in a patient with left ventricular assist device.
Busch MC, Haap M, Kristen A, Haas CS.
Ann Emerg Med. 2011 Jan;57(1):25-8. Epub 2010 Jul 31.
PMID: 20674087 [PubMed – in process]

[2] Thoratec HeartMate II LVAS – P060040/S005
FDA (Food and Drug Administration)
Device Approvals and Clearances
Device Approval Notice with links to FDA Approval Letter

[3] Successful biventricular circulatory support as a bridge to cardiac transplantation during prolonged ventricular fibrillation and asystole.
Farrar DJ, Hill JD, Gray LA Jr, Galbraith TA, Chow E, Hershon JJ.
Circulation. 1989 Nov;80(5 Pt 2):III147-51.
PMID: 2680160 [PubMed – indexed for MEDLINE]

I could not find this paper on Circulation’s site, not a link to the abstract. Maybe the Pt 2 means a part of a supplement, that is not included in the archives.

[4] Ventricular assist device support for management of sustained ventricular arrhythmias.
Fasseas P, Kutalek SP, Samuels FL, Holmes EC, Samuels LE.
Tex Heart Inst J. 2002;29(1):33-6.
PMID: 11995847 [PubMed – indexed for MEDLINE]

Free Full Text Article from PubMed Central with links to Free Full Text PDF download

Busch MC, Haap M, Kristen A, & Haas CS (2011). Asymptomatic sustained ventricular fibrillation in a patient with left ventricular assist device. Annals of emergency medicine, 57 (1), 25-8 PMID: 20674087

Farrar DJ, Hill JD, Gray LA Jr, Galbraith TA, Chow E, & Hershon JJ (1989). Successful biventricular circulatory support as a bridge to cardiac transplantation during prolonged ventricular fibrillation and asystole. Circulation, 80 (5 Pt 2) PMID: 2680160

Fasseas P, Kutalek SP, Samuels FL, Holmes EC, & Samuels LE (2002). Ventricular assist device support for management of sustained ventricular arrhythmias. Texas Heart Institute journal / from the Texas Heart Institute of St. Luke’s Episcopal Hospital, Texas Children’s Hospital, 29 (1), 33-6 PMID: 11995847

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Joint Commission – Anti-Safety in Action

At WhiteCoat’s Call Room is Joint Commission – Anti-Safety in Action.

Dr. WhiteCoat does a great job of explaining the idiocy of this attempt by JCAHO TJC (The Joint Commission) to prevent suicide in the ED.

What? You didn’t realize we are besieged by an epidemic of ED suicide? I guess you don’t drink TJC Brand Kool-Aid.

Go read this excellent article. My only disappointment was that Dr. WhiteCoat did not transfer the lost time into lives.

Here is my comment, but you have to read what Dr. WhiteCoat wrote first.

These rules will, at 10 minutes per patient, add up to a cost of 2,203 years of patients’ lives per year. If we divide that by the potential 5 patients per year, who might be saved if they respond positively to TJC ideas, that would be 440 years spent for each potentially prevented suicide.

This also raises a question. Should any positive response to any TJC ideas have its own DSM-V diagnosis?

For those who are not upset by the 440 patient years spent trying to save, and probably failing to save one suicide, remember that each of those screenings includes a nurse, too.

Not just 440 patient years per potential life saved, but 440 nursing years. A total of 880 years spent on this imaginary ability to prevent suicide by a TJC screening exam.

Where is the evidence that this intervention is in any way successful?

Where is the evidence that this intervention does not encourage patients to commit suicide at higher rates than if they did not have the screening?

Where is the evidence that this intervention does not encourage nurses to commit suicide?

With a lifespan of about 80 years, this is 5 1/2 patient lives – birth through to death at 80 years old – for each potential suicide saved and 5 1/2 nurse lives – birth through to death at 80 years old – for each potential suicide saved.

This isn’t at the level of Osama bin Laden or Timothy McVeigh, but it has potential. Especially if this encourages suicide. It’s TJC. Give them time to build up to their full serial killer potential. Don’t rush them.

That is not just 80 years of living – 11 times over, each year. No.

That is 80 years of non-stop TJC screening 11 times over, each year. No sleep. No food breaks. No interruptions from TJC screening. Sisyphus would be crying like a little baby. This would not be permitted at Guantanamo.

This is pure genius, in an extremely sadistic, I’m from the government and I’m here to help, kind of way.

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Do Drug Shortages Really Impact EMS? – Answer 4



Here is part 4 of the details from the points I raised in commenting on the discussion of the drug shortages and the way these affect EMS. Do Drug Shortages Really Impact EMS? – EMS Office Hours and followed by Do Drug Shortages Really Impact EMS? – Answer 1, then by Do Drug Shortages Really Impact EMS? – Answer 2, and that is followed by Do Drug Shortages Really Impact EMS? – Answer 3. This is broken up by answer. There are many points covered for a podcast that lasts less than 40 minutes. Do Drug Shortages Really Impact EMS?

4. Should CPAP (Continuous Positive Airway Pressure) be ALS (Advanced Life Support) only?

Somebody mentioned that CPAP is seen as invasive.

No. CPAP is not invasive.

CPAP falls into the category of NIPPV (Non-Invasive Positive Pressure Ventilation). CPAP has been used safely many places by BLS (Basic Life Support) personnel.

CPAP is a safe and effective BLS treatment for heart failure.

What if we think that medical command permission should be required for BLS to use CPAP?

If that is the case, then we should give CPAP to BLS personnel, train the basic EMTs to use CPAP, even require our magic phone call. Then, after we realize that there was never any good reason to prevent basic EMTs from using CPAP and we realize that the magic phone call is doing nothing to improve safety, but is probably only discouraging appropriate use of CPAP, then we can eliminate the magical medical command phone call ritual.

CPAP should be used aggressively for heart failure by everyone.

If anyone disagrees, please provide some evidence of harm.

Treatments for CHF –

Lasix (furosemide)? Does not decrease the need for intubation, does not improve survival, does not help, but can harm CHF patients and can harm patients with other medical conditions (e.g. pneumonia) mistaken for CHF.

High Dose NTG? Decreases the need for intubation, but is ALS.

ACE Inhibitors? Decrease the need for intubation, but are ALS.

CPAP? Decreases the need for intubation and is BLS. Possibly the best and safest treatment for CHF.

Why would anyone want to do something as dangerous as give Lasix, when there is something as simple and as safe as CPAP available?

I will write about the evidence for CPAP in another post.

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Failure Is an Option – Part II

Continuing what I wrote in Part I about the talk on education at TED Talks. Diana Laufenberg: How to learn? From mistakes. It is a 10 minute video, but the relevant part part I am interested in comes between the 6 minute and 7 minute points.

You have to be comfortable with this idea of allowing kids to fail as part of the learning process.

Don’t even suggest that EMS students should not be referred to as kids. The kids she is referring to are 11th grade students, old enough to fight and die for their country (although not old enough to buy alcohol), and not much younger than the typical EMS student.

Let’s look at some examples of our failures.

During transport, how many of us sit on the captain’s chair behind the patient, where we cannot see the patient?

How do we continue to assess our patient from there?

How do we recognize when something has changed?

Do we assume that nothing will change?

When we arrive at the hospital, how many of us disconnect the monitor/defibrillator and leave it in the ambulance?

Does a monitor/defibrillator only work in the ambulance?

Do we not bring the monitor/defibrillator in to the call for syncope patients, chest pain patients, or other ALS patients?

Do patients never have rhythm changes between the inside of the ambulance and the hospital bed?

How would we know if there is a rhythm change?

How would we shock V Fib without a monitor/defibrillator and without an AED?

If we do not need the monitor, then why did we attach the monitor to the patient at any point?

If we look at the patient’s rhythm, now, and see a sinus rhythm, what does that tell us about the rhythm before we looked at the rhythm?

When we leave the monitor in the ambulance, we are paramedics operating at a less than First Responder level.

This appears to be a form of patient abandonment.

We do not have to leave the patient to abandon our ability to care for our the patient.

We are called because something has gone wrong. Do we show up and choose a protocol and then never think about anything again?

This is failure.

We need to learn from these failures.

We need to learn to not defend failures.

We need to learn not to continually repeat failures.

We need to abandon the status quo and think about what is best for our patients.

If we just punish people for these behaviors, rather than educate them about why these behaviors are not good patient care, we can direct the Clipboard Nazis QA/QI/CYA people toward other things.

To be continued in Failure Is an Option – Part III.

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Do My Posts Authorize Protocol Violations


 

At EMS Office Hours is a podcast titled, A Few Realities Of EMS – It’s Not Puppies Dogs & Ice Cream Cones.

A couple of points are made. I am very critical of bad protocols, bad medicine, and just all sorts of things that I would change about EMS. Jim is right that I do not have the authority to change your protocols. It shouldn’t take a podcast for you to understand that.

In the sidebar of my blog, since I first started blogging with a blogspot address, has been a disclaimer. It is hidden over there under Sidebar Navigation (click on that and scroll up a touch to see the title – Sidebar Navigation). If you click on the link Disclaimers, you will be taken to a section, where I explain a lot of limitations on what I write.
 

I am not dispensing medical advice. If you get your medical advice off of a blog, instead of consulting a physician (such as your medical director), you probably should not be treating anyone, not even yourself. I could include your dog, but that would suggest that veterinarians do not provide excellent care. The veterinarians I know take pride in the care they deliver and deliver excellent care, more so than many people I know in EMS.

I do point you to research to support what I write, but you still need to make sure that you have the authorization of your medical director before changing any of your treatments. If your medical director does not agree, you can point to the research I write about. Most doctors do understand research, they just have trouble keeping up with the amount of research that is produced.

What I write does not change your protocols. If you do not like a protocol, take it up with the medical director. I have several inadequate protocols, too. I call medical command and attempt to persuade the physician that what I am requesting is in the best interest of the patient. It is rare that I am turned down, but the dose is often inadequate. I call back before I need more, so the patient does not have to put up with the On Line Medical Command delay in treatment. Health care providers should be anticipating where the care of the patient is headed – both for good and for bad.

 

I addressed these concerns long before I began writing about them on this blog.

There is a lot write about regarding the ethics of following bad protocols. This topic needs to be thoroughly covered, including these –

Does the use of restrictive protocols by a medical director (protocols that prevent appropriate care of their patients) constitute a form of patient abandonment?

How unethical is it to disobey unethical orders?

All protocols should include a statement that a medic should not follow the protocol if the medic believes that the treatment will harm the patient. I am still surprised that some protocols are written without this statement. This is irresponsible incompetent behavior by the author of the protocols.

Imagine being in court. Explaining giving a treatment to a patient that appears to have caused the death of the patient. Stating that the protocol must be followed, even when we expect the treatment to harm the patient.

Should we expect anything good to come from this?

Does this establish reckless disregard and gross negligence?

Would this create grounds for criminal charges, rather than just a civil malpractice case?

But these will be in other posts.

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Pat Robertson Makes Some Sense

As much as I am critical of Pat Robertson, I must give him credit for making a lot of sense, here.
 

[youtube]sQi7A5MW2kQ[/youtube]

Do our drug laws have any impact on the ability of high school seniors to obtain marijuana?

According to the chart I posted in More Examples of Errors Due to Confirmation Bias, almost all 12th grade students consider it fairly easy or very easy to obtain marijuana.[1]
 


 

Red is 12th grade. Blue is 10th grade. Green is 8th grade.

Could it be more clear that our drug policy has been a failure?

Could the TSA (Transportation Security Administration) do any worse, if the TSA were given as much money as we spend on drug policy?

The TSA provides security theater – the appearance of security, without the reality – should we describe the result of our drug laws as drug abuse containment theater?

Our drug laws do not even appear to provide the appearance of containment of illegal drug use.

Footnotes:

[1] Monitoring The Future
Drug and Alcohol Press Release: Text, Figures, & Tables
Web page with link to PDFs of the various data provided

Free PDF of the data on past 30 day use of all drugs from monitoringthefuture.org

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Failure Is an Option – Part I

There is a great talk on education at TED Talks. Diana Laufenberg: How to learn? From mistakes. It is a 10 minute video, but the relevant part part I am interested in comes between the 6 minute and 7 minute points.

What do you do when the information is all around you?

We need to teach people to be able to figure out what is accurate, what is partially accurate, and what is completely wrong.

Here’s the thing you need to get comfortable with when you’ve given the tool to acquire information to students. You have to be comfortable with this idea of allowing kids to fail as part of the learning process.

Not just as a part of the educational process, but as a part of the QA/QI/CYA/medical oversight process.

EMS is medicine.

In medicine, mistakes are made frequently.

We can work to minimize the frequency of medical errors.

We can work to minimize the frequency of serious medical errors.

We will not eliminate medical errors by punishing people for errors.

We only end up with a much bigger, much more dangerous error.

We end up with the protocol monkey – the cluelessly fumbling protocol monkey, who is just trying to avoid doing something that will result in punishment.

What we want is someone providing patient care with the understanding that the patient is a real human being, deserving of care. This person delivering care needs to be capable of assessing patients who do not present as the protocol writers would like them too. Someone capable of deviating significantly from what is prescribed by an inflexible protocol.

Trying to fit all human beings patients into rigid protocols is a fool’s errand.

Giving a box of drugs to someone, who is incapable of assessing patients and adjusting treatments appropriately, is reckless and irresponsible.

Errors are a part of medicine.

EMS is medicine.

We will not improve EMS/medicine by punishing errors.

We need to learn how to learn from errors.

We need to teach students how to learn from errors.

We need to teach EMTs and paramedics how to learn from errors.

To be continued in Failure Is an Option – Part II and later continued in Failure Is an Option – Part III.

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4 Way Stop – 5 Vehicle Collision

Not just 5 ordinary vehicles. 3 cars, 1 ambulance, and 1 firetruck.

7 people transported to the hospitals.

W Tabor Road and Wagner Avenue in Philadelphia is a 4-way intersection controlled by 4 stop signs. This suggests that someone was unfamiliar with the area, that one (or more) of the stop signs were knocked down, or that one (or more) of the vehicles did not even come close to being able to stop did not stop for the stop sign.

Several fire vehicles and a medic unit were responding to an accident report shortly before 6 p.m. when two of the vehicles collided with a taxi and two other private automobiles at Tabor Road and Wagner Avenue, Ayers said.[1]

I am not an advocate of coming to a full stop for a stop sign or a red light. The driver is responsible for the safe operation of the vehicle and should use good judgement to determine the appropriate speed through any red light or stop sign. It appears that at least one of the drivers did not exercise any judgment.


Picture credit[2]

There is also audio of the radio broadcasts after the crash.[3]

Footnotes:

[1] Fire, medic vehicles crash in Logan
Posted on Tue, Dec. 21, 2010
by Robert Moran
Philly.com
Article

[2] Firetruck, Ambulance, Cars Crash in Logan
NBC Philadelphia
First Published: Dec 21, 2010 10:48 PM EST
Updated 11:00 PM EST, Tue, Dec 21, 2010

[3] Philadelphia FD – Departmental Crash – 12/21/10 – 1800 Hours – West Tabor Road and Wagner Avenue
Audio of radio communications after the crash

While responding to an alarm – Squad 72 and Medic 18 were involved in a Crash with 3 other Vehicles. Reports indicate that 4 Fire Personnel and 2 Civilians were injured. A total of 5 Medic Units were requested to the scene. The audio below is a 40 minute period – condensed into 7 minutes.

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