Category: Cardiac Ischemia

Nitro and SBP drop by 1/3

Question #: 412


Nitro and SBP drop by 1/3

Protocol states NTG SL is contraindicated if SBP drops by 1/3 or more of INITIAL value after NTG administration.

If my first BP reading is 180/90, and after interview I determine NTG is appropriate but it has been greater than 5 since acquiring a BP and I decide to acquire a "fresh" BP just prior to admin and it comes back 150/90, should I consider the initial SBP 180mmHg or 150mmHg? Sorry if it seems obvious, was wondering if perhaps the pt was anxious and had relaxed a bit and if I should go off the BP just prior to the first NTG admin.



RPPEO’s recommendation is to follow the Medical Directive parameters as they were designed for patient safety. We agree that in the situation you are presenting, the presence of Paramedics on scene and the therapeutic conversation may have potentially lowered the blood pressure. However, when the blood pressure drops by 1/3 from the initial, even if the systolic blood pressure is 150, there is still a concern for a Right Ventricular Infarct that cannot be ruled out by the diagnostic tools you currently have on the road. Further, in suspected cardiac ischemia, ASA has demonstrated benefits, influencing morbidity and mortality with minimal risks. Nitro is considered beneficial to relieve active ongoing symptoms, with risks to hemodynamic stability and perfusion. That said, in this specific case, there are 2 possible options that could be appropriate to tailor the management plan to your patient: a) withholding nitro for the rest of the patient encounter; and b) consulting with a Base Hospital Physician and decide together what the best course of action would be for your patient. Please ensure information, clinical picture, pertinent +/- and rationale supporting your management plan are documented.

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