ECG in ambulance saves lives after heart attack

A new study from the University of Surrey, published in the journal Heart, has identified a positive link between the survival of heart attack patients and the use of an electrocardiogram (ECG), by ambulance crews.

Researchers, funded by the British Heart Foundation (BHF), analysed data from almost half a million adults admitted with a heart attack to hospitals in England and Wales, noting whether patients who came to hospital by ambulance had had an ECG test or not.

The results showed that the number of patients who died within 30 days of hospital admission was significantly lower when an ECG test had been carried out by ambulance crews. The study also revealed that a third of patients admitted to hospital with a heart attack are not having the test in the ambulance, with certain groups of patients, including women, the elderly and people from black and minority ethnic groups, less likely to have an ECG. A further important finding from this study was that having an ECG in the ambulance was also the strongest predictor of a patient receiving treatment to reopen a blocked coronary artery. The use of this treatment is proven to reduce heart damage and improve the survival of patients.

Lead author, Professor Tom Quinn from the University of Surrey, said: “Every NHS ambulance is equipped with an ECG machine. While there is evidence from other countries that having an ECG test in the ambulance leads to faster treatment, our study is the first to determine that the test is actually associated with improved survival after a heart attack.

“Ambulance services in the NHS compare favourably to countries such as the USA, where only a quarter of such patients get an ECG, but we need to do more to ensure that the groups we identified as not getting the test have improved care.

“Hopefully our results will reinforce to paramedics the importance of carrying out an ECG when they suspect a heart attack, as well as flag up the types of patients who are currently less likely to receive this test, leaving them more vulnerable to poor outcomes.”

Dr Mike Knapton, Associate Medical Director at the BHF, said: “This research suggests that if someone suffering a suspected heart attack has a simple ECG test before they reach hospital, it can help save their life. The test helps paramedics provide the most appropriate treatment outside hospital and means that hospital staff are more prepared when the patient arrives.

“The results, made possible by studying huge numbers of medical records, clearly support existing guidelines on using an ECG test before patients reach hospital. So it’s vital that all patients who show signs of a heart attack have this simple test.”

http://www.medicalnewstoday.com/releases/275531.php

Picture courtesy of www.heartresearch.com.au

How to Replace IV Nitroglycerin in the Shortage

For the last month, Nadia Awad, PharmD, and her ED team at Somerset Medical Center in New Jersey have struggled with a shortage of nitroglycerin.

“IV nitroglycerin is really our workhorse for myocardial infarction, hypertensive crisis, and acute decompensated heart failure,” Awad tells MedPage Today. “Alternatives are scant and often associated with adverse events.”

An emergency department nightmare is now reality: Manufacturing problems havesapped intravenous nitroglycerin supplies, leaving many ED teams across the country without the go-to drug. Last week, the New York Times reported that the sole manufacturer of nitroglycerin right now in the U.S., Baxter International, cut shipments of the drugbecause it could not keep up with demand.

The healthcare community must find long-term solutions to the shortages, but the critical question right now was captured in a tweet by Patrick Bafuma, RPA, an ED physician assistant at Mount Sinai Hospital: “Nitro drip in short supply. Backup plan for APE [acute pulmonary edema resulting from acute decompensated heart failure]?”

So what are the alternatives?

1. Slather Nitro Paste

In acute coronary syndrome, Bryan D. Hayes, PharmD, an ED pharmacist and toxicologist at the University of Maryland, recommends ED physicians reach for an alternative formulation, such as nitro paste or sublingual tablets. Hayes says the shortage has choked their hospital’s IV nitroglycerin inventory down to a few bottles. The Emergency Medicine PharmD blog offers a handy pharmacy consult for conversions between IV and paste nitroglycerin.

Still, in APE, Bafuma said he tries to avoid nitro paste because delayed onset makes it unpredictable.

2. Use Spray Nitroglycerin

For APE, Justin Hensley, MD, an assistant professor of emergency medicine at Texas A&M Health Science Center and an ED physician at CHRISTUS Spohn, said he uses 400 mcg of nitro spray and titrates one spray every 4 minutes, which results in a 100-mcg per minute dose.Corey Slovis, MD, chair of the department of emergency medicine at Vanderbilt University in Nashville, Tenn., said the spray could be a good option and emphasized that titration is key to this setup. This is the route Bafuma said he’d try.

3. Give Sublingual Nitroglycerin

Anand Swaminathan, MD, an assistant professor of emergency medicine at New York University and an ED physician at Bellevue, prefers giving multiple sublingual tablets of nitroglycerin instead of using nitro paste. With one 400-mcg tablet, Swaminathan said absorption is roughly 70 to 80 mcg/min.

Slovie says that there is an additive effect. “If blood pressure holds after about 5 minutes, we double the dose,” Slovis writes in an email.

“Because some patients’ blood pressure drops with nitroglycerin, we start with one sublingual nitroglycerin tablet,” Slovis says. “Then we go up from there and then escalate to bilevel positive air pressure (BiPAP) or continuous airway pressure (CPAP) with nitroglycerin in the most severely ill patients.”

The team x-rays the chest to confirm fluid overload before starting furosemide (Lasix). That’s because symptoms are sometimes confused with COPD exacerbation, pneumonia, or lung cancer, and giving furosemide can make them much worse or increase mortality (see loop diuretics below).

If the patient is wheezing, Slovis said they also use a bronchodilator. When more nitroglycerin tablets are needed, they remove the mask briefly.

4. Drip ACE Inhibitors

For acute heart failure, Hayes recommends enalaprilat for preload reduction and nicardipine for afterload reduction. Swaminathan also would consider enalaprilat, not as a complete alternative, but in addition to other agents for APE. He likes it because the ACE inhibitor “cuts off the neurohormonal activation,” and Swaminathan usually starts with low dose enalaprilat 1.25 mg IV. The exception would be hypotensive patients.

5. Try Nitroprusside

Hayes says nitroprusside reduces both preload and afterload, though he points out he’s seen the price skyrocket recently. There are some concerns about cyanide toxicity upon metabolism, though Slovis said such events were “really, really rare and never in the ED” because that would take a really long time and high dosages.

Still, Awad, a clinical assistant professor of pharmacy at Rutgers, felt it was important to note that nitroprusside would not be a good choice for patients with hepatic or renal failure. For faster onset, fewer dose adjustments, and fewer adverse events, nicardipine might be a better choice to control hypertension (see below).

6. Consider Nicardipine

For acute decompensated heart failure, Awad highlights a study that suggests 1 mcg/kg/min of nicardipine is the optimal dose for patients. Earlier this month, Awad investigated nicardipine’s role in acute decompensated heart failure.

Drugs to Avoid

Nesiritide

Some may be curious whether they ought to bring nesiritide back after it flopped in acute heart failure, especially if some hospitals were slow to stop stocking it. Awad reviewed the literature and concludes it was shelved appropriately. Swaminathan also dinged nesiritide.

Loop Diuretics as First Line

In the past, doctors chose loop diuretics such as furosemide because they believed APE stemmed from volume overload, according to Swaminathan. He called that an urban legend at the recent American Academy of Emergency Medicine conference, and wrote that recent studies have shown it’s actually fluid shift.

“[Furosemide has] no role until you reverse the severe increased afterload and turn off the neurohormonal cascade,” Swaminathan said. “Lasix makes patients worse in the first 10 to 20 minutes of management, which is the critical time in APE resuscitation.”

Here’s Slovis’ Protocol During the Shortage

Sublingual nitroglycerin, 1 to 2 tabs every 5 mins x 3 — reassess BP

If well controlled, then transition to NTP or Isordil p.o. (Nitro paste or longer acting NTG)

If not well controlled (>160/100) then consider, in no particular order:

1) IV enalapril — 0.625-1.25 mg IV bolus

2) IV hydralazine 5-10 mg IV bolus

3) IV nitroprusside

“The data for these drugs in the ED is limited, but they are reasonable alternatives,” says Slovis. The bottom line is that none of these options replace IV nitroglycerin. Slovis added, “Each doctor is trying to do their best without the best drug.”

http://www.medpagetoday.com/EmergencyMedicine/EmergencyMedicine/45056