chest pain scenario

[Medivixen]

Entonox = Nitrous Oxide

here's a little something from my monographs. We can admin entonox for pain prn... pretty basic stuff; our first responders can get an endorsement for it even. Handy!


NITROUS OXIDE (ENTONOX)

Classification - An inorganic compound made of ammonium nitrate. Analgesic.

Mechanism - Inhalation of a 50% mixture of Nitrous Oxide and oxygen produces CNS depression as well as rapid pain relief (Pharmacology for Prehospital Emergency Care, pp. 127-8).
Analgesic working specifically on the central nervous system (Pharmacology in Nursing, p. 305).


Indications:
• Relief of moderate to severe pain from any cause:
acute myocardial infarction
musculoskeletal trauma
burns
other conditions (e.g., ureteral colic, labour)

Contraindications:
• Any altered level of consciousness such as head injury (masks neurologic signs one needs to monitor)
• Acute pulmonary edema (these patients require 100% oxygen)
• Known pneumothorax or chest injury (Nitrous Oxide collects in dead air spaces)
• Decompression sickness
• Air embolism
• Cyanosis develops during administration
• Inability to ventilate an enclosed treatment area (e.g. air transportation)
• Patient has taken Nitroglycerin within the last 5 minutes
• Inhalation injury

Cautions:
• Abdominal distension (absent bowel sounds)
• Shock
• Chronic obstructive pulmonary disease
• Major facial trauma
• Patient has taken a depressant drug
• Improper storage
Low temperature (NOTE: storage below -6 degrees C: gas will separate.
[ref. EMA I Update: Entonox Protocol, Paramedic Academy, 1993])
Stagnant
Vertical position
• Combustion/inhalation/dependence

Dose:
• Self-administered. As the patient becomes drowsy, the mask / mouthpiece will drop away from the patient's mouth / face.
• Patient controlled until pain is relieved.

ADVERSE AFFECTS - There are nine common adverse affects in the use of Entonox:
• aggravation of middle ear (increases pressure)
• drowsiness
• nausea
• vomiting
• giddiness
• dizziness
• amnesia
• decreased level of consciousness
• decreased cardiac output



And if for nothing else, you can inject it into the cylinders of the engine of your bus and really jam your patients to the ER and set a golden hour speed record at the same time!

 

[slallak]

if his BP is really that high (160/78) and he took the pill (lets say it was viagra) last night go ahead and give him the nitro. You are going to call for als back before that I hope. I would have. His BP is high enough that it probably wont hurt. Then load and go.

 

[Ridryder911]

It's obvious most of you have never seen NTG effects on Viagra, or even right side infarcts. What are you going to do when their pressure drops to 60/20 ? If a physician orders it, then the are taking the risks.

Congrat's you just increased the infarct size..!

R/r 911

 

[yowzer]

It's obvious most of you have never seen NTG effects on Viagra, or even right side infarcts. What are you going to do when their pressure drops to 60/20 ? If a physician orders it, then the are taking the risks.

Congrat's you just increased the infarct size..!

R/r 911

Plenty of people have little bottles of ntg tabs to take when they get an angina attack or other chest pain. They're not doing 12-leads on themselves to look for a right-sided MI first (Or even taking a blood pressure.)

Is it a rare enough site for an MI that the risks are worth the benefits for nitro in general?

 

[Ridryder911]

Really no. They are studing the number of induced or enlargement of AMI's caused by NTG. That is why discussion of possibly removing NTG from basic EMT criteria if the patient does not have previous hx. of angina or if the patient has not been treated previously with NTG.

Not only right side side infarcts but some lateral and posterior wall as well as progressive transmural infarcts have been increased with the effects of NTG.

Remember, there is a difference from angina, and AMI. The problem is differentiating the two.

True, NTG may not always increase or even effect a ride sided AMI. But, again the would you want to be on the side of the roll of the dice ?

Personally, my medical director no longer wants NTG administered until inferior wall is cleared. You will see more and more of this as research continues.

Nitroglycerin is a wonderful drug/medication but like any other it has side effects and should only be used with appropriate indications. The treatment of angina as determined by a thorough an accurate history and physical exam and other conditions have been ruled out.

I have been on more than several calls with syncopal episodes from administration of NTG. As well have seen hypotensive episodes from NTG. Remember what occurs in hypotension, as the baroreceptors sense low volumes. Heart rate increases as well as contraction strength, which causes an increase work load on the heart. Thus increasing a larger AMI.

Of course until new standards comes out we will continue to perform as instructed and currently taught, just a "heads-up" on the potential changes in a couple of years.

R/r 911