Couple questions about nipride

I had a 91 year old patient the other night with a nipride drip. They started her on it at 0.125 mcg/kg/min because the RN made a good judgment call that she may react more sensitively to it, which she did. She went from a SBP of 200 to 150-160 immediately. The highest I had it all night was 0.5 mcg/kg/min before I gave her PO meds which required me bringing it back down to 0.33 mcg/kg/min and leaving it there at end of shift for a SBP around 165.

Here's my questions:
1) In your experience, are all elderly this touchy to nipride? She had no kidney or cardiac issues to complicate things, she was just really sensitive.

2) I clarified that the order was for a SBP 160-180 since the day shift PA wrote SBP > or = to 160 which wasn't enough clarity for me. After I titrated it a bit and got her to the upper 170's she had a large increase in her urine output. She put out 750 mL in a 2 hour period, then kind of hung around maybe 80 mL/hr afterwards. My preceptor attempted to explain why the high blood pressure increased her urine output, but it wasn't a super detailed explanation, all she said is that her kidneys are perfused better with a higher blood pressure. Can someone explain the hard physiology behind why that occurred?

You are right, I meant gomere. I must have forgot the gender the OP referenced.

You are right, I meant gomere. I must have forgot the gender the OP referenced.

1) From your description of this gomer it sounds like you were dealing with someone that has chronic hypertension that appears to be poorly controlled. People with hypertension are almost always going to be hypovolemic. Usually what maintains the hypertension is elevated systemic vascular resistance (SVR). Nitroprusside is a potent arterial vasodilator. Once the arteries dilate the SVR drops, the hypovolemia is unmasked and what you get is hypotension. Remember, Blood pressure = Cardiac Output X SVR. So, it is not that the gomer population as a whole is sensitive to nitroprusside. Personally, I think it is an old school drug that needs to be phased out as there are better and safer alternative concoctions available today.

2) Again, assuming you are dealing with a chronically hypertensive patient, your preceptor was right. Look into the autoregulation curve. In a normal person, perfusion to organs is maintained between a mean arterial blood pressure (MAP) of 60-150 mm Hg. Some references will vary depending on who you look to between 5-10mm Hg on both sides of the spectrum. Renal blood flow is no different. Afferent arterial tone and resistance will allow a fairly constant blood flow until you drop below a MAP of 60 or go above a MAP of 150.

In people that are hypertensive the autoregulation curve shifts to the right meaning that they need a higher MAP to perfuse the beans. People who take their pills and keep their blood pressure under control can actually shift the curve back to the left; however no one ever takes medications as prescribed so this is rarely seen. It sounds like this gomer needs a MAP greater than 80 or 90 to maintain autoregulation. Simply put, get her MAP up and she will pee, drop it and the foley bag will resemble the Sahara Desert.

patient is not in an ER....hence Get Out of My ER wouldnt apply.....and there wasnt sufficient description of patient to see if she would have qualified for the term.....and yes it was rather crude