Stressed out while anesthetized?

October 17, 2011 9:26 AM

Super high blood pressure during anesthesia?

I had surgery last week and was under general anesthetic for about 4 hours. When I came in for surgery, I felt spazzy and wiggety-wack and my blood pressure (normally 105/60 or so) was really high -- 140/85. The anesthesiologist said she would watch out for it during the procedure, but that it was common for people to have elevated blood pressure prior to surgery.

The surgeon was very concerned that during the procedure, my blood pressure spiked to 135/80. The anesthesiologist gave me medication, which apparently worked, and my blood pressure came down. When I came in for my follow-up, the surgeon said that although it is normal to have a stress response prior to surgery, that stress response is not present during anesthesia, so high blood pressure during surgery indicates a problem like pre-hypertension. My dad, who trained in surgery when dinosaurs roamed the earth, says that's ridiculous. If it matters, I'm female, mid-30s, in excellent health, and somewhat resistant to anesthetic --local doesn't seem to work well on me, and I've popped awake very quickly from general anesthetic.

I will ask my regular doctor when I see her next, but am curious if it's possible or likely that high blood pressure during anesthesia is some sort of tip-off for hypertension and whether it's possible for the body to experience stress under anesthesia.

posted by *s to Health & Fitness (9 answers total)

I'm not an anesthesiologist. But I do play one on tv work with them. And I recently had a long conversation about current practices, especially as they relate to blood pressure during general anesthesia. There are some new technologies that are in use which allege that they can monitor heart pressure and volume essentially using an algorithm to make decisions about hydration. It's a much less invasive process than some of the other standard monitors that were in place once upon a time. However, the doctor I spoke to expressed concern about this method particularly because it (in his opinion) amounted to cruise control for anesthesia. He was not thrilled at that prospect, but it sounds like opinion among anesthesiologists was divided. Anyway, long story short: hydration issue?

Finally, this was specifically related to thoracotomy (chest cavity surgery), possibly relevant to your surgery. It's important to note that all forms of anesthesia aren't created equally and they require different things. This was driven home when I was speaking to an anesthesiologist who specializes in "awake craniotomies." That's where they keep you awake and poke around at your brain. o_O

I have no idea how relevant or useful this information is. But gosh I thought it was interesting.
posted by jph at 9:55 AM on October 17, 2011 [1 favorite]

I'm not a doctor, or anything.

But 140/85, is, as far as I know, not "really high" BP. It's actually not even moderately high. 120/80 is normal. Yours tends to run fairly low. 140/85 would be moderately high "pre-hypertensive" if you had it on successive MD visits. It's probably just your bodies response to a traumatic experience (surgery/pain/anesthesia).

Like I said, I'm not your MD but this quite possibly is entirely within normal limits.
posted by sully75 at 10:04 AM on October 17, 2011 [1 favorite]

You cannot make a diagnosis of hypertension based on two readings, once when the patient is stressed and once while they are under anesthesia. If your regular doctor wants you to track it for a few days, fine. But try to make sure no one writes "hypertension" anywhere near your records unless you actually have it, because it will really fuck with your ability to get insurance.
posted by Nothing at 10:12 AM on October 17, 2011 [1 favorite]

Also not a doctor but while 140/85 may only be 'moderately high' under normal circumstances, that may not be the case while unconscious and it certain seems problematic if the OP has had a recent reading of 105/60.

What the surgeon said makes sense to me (the part about it not being a stress-response if you're anaesthetised ) but I wouldn't worry about it, just get your blood pressure checked with your regular doc at your next appointment.

Did you dream during the procedure?
posted by missmagenta at 10:19 AM on October 17, 2011

People's bodies respond to anesthesia differently, and need different doses to keep them blissfully unaware throughout a procedure. It sounds like you tend to metabolize these drugs pretty quickly. I'm not speaking from any sort of experience here, but it's possible that your blood pressure spiked because the drugs were wearing off just enough for you to experience a stress response, even though you were not consciously aware of it.

Whatever the cause, I agree that you would need a lot more BP readings under a lot more normal circumstances to determine that anything troubling was going on. Maybe check it yourself at Walgreens, and have your primary care provider keep an eye on it when you go to the clinic.
posted by vytae at 10:49 AM on October 17, 2011

Best answer: IANAD but I am a medical student recently off my surgery rotation. A couple of points:

- There are several different aims of anesthesia. The sort of obvious one is to make you unconscious, but they also want you to feel no pain, be perfectly still, and not remember the procedure. There is no one drug that does all of this, so several drugs are used. Some of the drugs are better at making you unconscious, some are for making you stay still, some are for making your nervous system not react to being diced open. They are used throughout the procedure, not just at the beginning; your anesthesiologist is doing touch-ups every so often to keep you in a good safe place for the whole four hours.

- The situation arises pretty frequently in the OR that someone is unconscious and perfectly still, but all of a sudden their blood pressure and/or heart rate starts going up. The anesthesiologists usually interpreted this a reaction to pain (because even though your mind is out, your body is still responding to trauma by releasing adrenaline, etc), and gave the patient some more painkillers, which usually resolved the problem. So it's totally possible to be under anesthesia and still be having a stress response. It's not as robust a response as you would have were you awake, but it's still definitely happens.

- 140/85 is high for you but not high in any absolute sense. Definitely not super high. It may be a little unusual given the sedating medications you were on at the time (which tend to lower blood pressure), but I've never heard that an over-vigorous stress response during surgery had any implications for someone's resting blood pressure or future risk of hypertension.
posted by half life at 10:58 AM on October 17, 2011 [3 favorites]

Well, going on at pre-hypertension might be a stretch. One of the causes of operative hypertension is plain old hypertension, which is not uncommon as an incidental finding. They may be saying you should check with your primary care doc, as white-coat nervousness shouldn't matter once you're out. And yes, BP spikes during surgery happen.
posted by a robot made out of meat at 11:08 AM on October 17, 2011

Response by poster: Did you dream during the procedure?

No, but I have a vague sense of having heard the surgeon talking. Can't recall specific words, so maybe it happened, maybe it didn't.
posted by *s at 11:33 AM on October 17, 2011

Best answer: I am an anesthesiologist and am kind of surprised that they even thought this was worth mentioning to you, given the situation as you describe it. As was mentioned above most of the drugs used for sedation and anesthesia tend to decrease blood pressure while the stimulation of surgery tends to increase it. It is possible to completely abolish this stress response (there is even a specific term for that dose of anesthetic), but that can be undesirable if it means you are having to battle low blood pressure the whole case. Sometimes there is a wait between induction of anesthesia and incision (while the patient is positioned, prepped, and draped, x-rays may need to be reviewed, they may be waiting for instruments, the surgeon may be busy with something else, and so on) and during this time very little anesthetic is needed and too much will cause low blood pressure and heart rate; at incision it is not unusual for the blood pressure and heart rate to jump up until the ideal depth of anesthesia for that patient is found. Also it is common in this day and age to give patients as little anesthetic as possible (both to minimize anesthetic complications and to speed up emergence from anesthesia) which means that spikes in blood pressure are more likely to occur. Of course this also makes intraoperative recall more likely and your statement "I have a vague sense of having heard the surgeon talking. Can't recall specific words, so maybe it happened, maybe it didn't" is actually a pretty classic description of the most common form of surgical recall. It is also possible that you heard the surgeon as you were going to sleep or waking up, so I wouldn't say you definitely had recall, but it is possible and consistent with relatively light anesthesia and spikes in blood pressure.

As for the numbers you give, ideally we try to keep the blood pressure within +/- 20% of the preoperative value. You were outside those parameters, but not by much. By way of comparison I have seen sick premature infants with blood pressures around 60/30 and a patient who got (in retrospect) too much epinephrine with a blood pressure briefly approaching 300/200. The standard number for canceling surgery is a diastolic pressure (the lower number) of 110 mmHg. So your pressure was nowhere near any of those numbers.

So in general I tend to agree with your dad; I also kind of wonder if the surgeon is trying to send a subtle message to that anesthesiologist that he is keeping his patients too light. This is all speculation, of course, but the bottom line is that you should check your blood pressure and overall health just like anybody else, but the situation you describe is nothing to worry about. Feel free to let me know if I need to expand on this answer.
posted by TedW at 12:17 PM on October 17, 2011 [4 favorites]