Beta Blockade

[jetproppilot]

All right Dudes/Dudettes,

we all know about the literature showing protection from myocardial ischemia/infarction by beta-blockade in at-risk patients in the peri-operative setting.

SO,

WHAT CONSTITUTES BETA BLOCKADE????

Labetolol 200mg PO in day surgery at 0630? Labetolol 5 mg IV shortly after induction?

OR, does the beta-blockade have to be started a few days before surgery and be steady-stated in order to "work?"

Bring the answers, literature hounds. Very important subject that I dont think has been made very clear. Yes, we know the theory. But how to implement it?

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[toughlife]

There does not seem to be many studies that specifically address the dose issue pre-operatively.

CLINICIAN'S CORNER
-Blockers and Reduction of Cardiac Events in Noncardiac Surgery
Scientific Review

Andrew D. Auerbach, MD, MPH; Lee Goldman, MD


JAMA. 2002;287:1435-1444.


When Should -Blocker Use Be Started Preoperatively and When Should It Be Discontinued?

Although questions remain regarding the optimal dosing schedule for perioperative -blocker therapy, investigations showing a positive effect sought to achieve sympatholysis before induction of anesthesia. Thus, physicians should try to begin therapy early enough so that doses can be titrated appropriately. The time required to meet this goal may vary, depending on the agent, the route of administration, or patient factors, but it is clear that a physiologic dose of -blocker must be administered for any positive impact to be appreciated. For example, intravenous atenolol, as used by Mangano et al,42 may be administered and titrated to a physiologic dose in the preanesthesia holding area or even the operating room. Physicians who choose to begin -blocker therapy orally may require additional lead time for patients to reach the target heart rate. In fact, patients in Poldermans' study45 began oral therapy 1 month before surgery, on average, with titration of the dose performed at a visit 1 week after initiation of bisoprolol.

Postoperatively, most protocols extended beyond the first postoperative day and even up to 1 month after surgery. Nonrandomized data from Shammash et al55 and previous case reports suggest the hazards of discontinuation of -blockers immediately postoperatively. A recent study suggested that, among vascular surgery patients who had not been receiving -blockers long-term, continuing -blockade up to 3 years after surgery reduced cardiac mortality.70 Although tantalizing, these results are based on a small number of patients (n = 112) with a high burden of cardiovascular illness and need to be reproduced in larger, less selected cohorts.

The safest conclusion to be drawn from current studies is that -blocker use should begin before surgery, even up to a month before the procedure, with titration of the dose taking place as an outpatient procedure and up to the induction of anesthesia. Therapy should be continued at least through hospitalization, and longer if adequate medical follow-up can be arranged postoperatively. Close follow-up is particularly important in the care of patients who were not receiving -blockers long-term before surgery so that the drug dose can be tapered if long-term use is not indicated. Follow-up is also imperative for patients receiving -blockers for medical reasons so that continuity in their medication is maintained.

Ample evidence suggests that long-term -blocker therapy is underused in patients with definitive indications.71-77 Thus, the perioperative period may represent an opportunity to begin -blocker therapy in appropriate patients, such as those with a history of myocardial infarction.

Long-term use of -blockade for patients with heart failure has been clearly shown to improve patient mortality,78 and these patients might also be identified perioperatively. However, guidelines for administration of these agents in patients with heart failure require close monitoring,79 and the doses administered are usually far lower and not titrated to heart rate. -Blockade in these patients, therefore, should not be routinely started for prophylaxis perioperatively.

 

[VentdependenT]

Was there a basis on heart rate, something less than 70? I dunno man.

All the hooplaa about b-blockade intra op but as far as post op mortality goes your beta blockade is only as good (in preventing or mitigating coronary events) as the gp who continues it.

Anypoops you "should" start it a couple a weeks to a couple a days prior to surgery and continue it afterwards.

 

[militarymd]

One of my favorite drugs. This is the study that is referenced the mostUnfortunately, labetalol, the one drug that anesthesiologists use the most, had never been shown to provide perioperative or for that matter...anytime at all myocardial protection.

The data supports use of beta selective beta blockers..(alpha effects are no good)....so propranolol, metoprolol, bisoprolol, atenolol..

there is actually association between alpha blockade and CHF...ALLHAT trial.

I think it only makes sense that we use some kind of sympatholytic in the perioperative setting....period of high catecholamine state....we always treat pain...why don't we always treat the high catecholamine state?

 

[jetproppilot]

One of my favorite drugs. This is the study that is referenced the mostUnfortunately, labetalol, the one drug that anesthesiologists use the most, had never been shown to provide perioperative or for that matter...anytime at all myocardial protection.

The data supports use of beta selective beta blockers..(alpha effects are no good)....so propranolol, metoprolol, bisoprolol, atenolol..

there is actually association between alpha blockade and CHF...ALLHAT trial.

I think it only makes sense that we use some kind of sympatholytic in the perioperative setting....period of high catecholamine state....we always treat pain...why don't we always treat the high catecholamine state?

Very compelling.

So Mil, a dude with risk factors presents for elective surgery, say a lap-chole (which happens virtually every day I go to work). No pre-op beta-blockade-regime in place. Stable clinically, but again, no beta-blockade initiated.

Is it worth initiating some type of beta-blockade at this point, and if so, whats the best plan of action? A PO beta-only (atenolol, propranolol, etc) in day surgery? IV propranolol after induction?

A newly beta-blocked patient offers challenges to the anesthesiologist...since most of what we give delivers a "calming" hemodynamic effect...in other words, beta-blockade pre-op means you have to be careful with "normal" induction doses, or post-induction BP will be 60/40...how is this addressed? I guess 100mg propofol instead of the routine 150....

I'd love to start some automatic-protocol to address those who could benefit from perioperative beta-blockade...but dont know if its even possible to address this issue when your first encounter with the patient is on the day of, or the day before surgery.

I have a buddy who is an MD at a surgery center who gives PO captopril pre-op to almost every pt...and he swears by it's "railroad track producing" hemodynamics....whats your take on ACE for ameliorating labile hemodynamics?

 

[Noyac]

In my opinion, the betablocker needs to be started soon enough to have the pts HR around 60bpm b/4 surgery. Really, I don't care if its there for a month or a week or a day. It just needs to be there the day of surgery. Then I feel the best course would be to continue the therapy for at least a month post op however, I feel that many of these pts should remain on betablockers indefinitely.

Check out this site:
http://www.cardiacengineering.com/

There is a good protocol/algorithm on the site as well by Art Wallace, MD. on page 2 of the betablocker protocol.

 

[nitecap]

Funny you say be on them indef. An attending once told me jokingly of coure that they should put beta blockers and a small dose of asprin in drinking water similar to fluorinating and require all over 45 to drink only that.

 

[militarymd]

I have a buddy who is an MD at a surgery center who gives PO captopril pre-op to almost every pt...and he swears by it's "railroad track producing" hemodynamics....whats your take on ACE for ameliorating labile hemodynamics?

That's something I have been thinking about doing. There are so many things that I think would be good ideas in the practice of anesthesiology (ie. good medicine) that we don't do because of the "business" of anesthesiology (efficiency) because we can "get away" with it.

My personal practice is if I run into a patient with intermediate/major clinical predictors going to the OR for intermediate/high risk surgery, I will give IV metoprolol to target a HR less than 70 bpm prior to induction and realize that I may need to adjust induction doses to prevent hypotension.

I think it only makes sense....we know that surgery causes your stress hormones (epi, norepi, renin, aldosterone, ADH, etc) to be eleveated in the OR and afterwards even with adequate narcotics.....why shouldn't we give drugs to block or counter these hormones.

 

[Noyac]

My personal practice is if I run into a patient with intermediate/major clinical predictors going to the OR for intermediate/high risk surgery, I will give IV metoprolol to target a HR less than 70 bpm prior to induction and realize that I may need to adjust induction doses to prevent hypotension.

Ditto.
Metoprolol instead of versed pre-op.

 

[jetproppilot]

My personal practice is if I run into a patient with intermediate/major clinical predictors going to the OR for intermediate/high risk surgery, I will give IV metoprolol to target a HR less than 70 bpm prior to induction and realize that I may need to adjust induction doses to prevent hypotension.

Ditto.
Metoprolol instead of versed pre-op.

or, ultimately, concominately, albeit with less benzo... (maybe 1mg)...cuz lets face it...an amnestic patient is a happy patient....

Someone who says to you, after you extubate them at the end of the procedure, "When are we gonna start?"...points to the Holy Grail of our profession.

SO, attendings et al, lets arrive on a pre-op beta blocker drug and dose PLUS a pre-op benzodiazepine dose that we'll start at, in said at-risk patients, in an attempt to fulfill the perioperative-beta-blockade miracles PLUS the "I'm comfortable and amnestic" miracles.....

gimme a lee-way dose of metoprolol...x mg to x mg? Plus 2-5 mg midazolam??? Or should we go with the archaic propranolol 1-2 mg IV?? (Whats the PO dose of propranolol? Should we give this in Day Surg?)

OR Atenolol PO in Day surg???

OR Metoprolol in Day Surg?

Lets see some conviction here. There are alotta things I can render opinions on with a vengeance, but peri-operative beta-blockade, which agent is better, etc, is not one of them.

Assume we all are privy to the effectiveness of peri-operative beta-blockade on preventing peri-operative myocardial ischemia/infarction.

Whats the recipe to the Holy Grail????

 

[militarymd]

I'm afraid I don't there is a set regimen....at least one that know of.,... I personally just titrate to get a slow heart rate....as polderman did in this study...with metoprolol.

 

[Noyac]

I'm just not a big fan of versed unless the pt is obviously anxious. My pts still wakeup asking "when are we going to start?" I will go a whole day or two without giving any versed. I mostly use it for preop blocks.

 

[eagle26]

One of my favorite drugs. This is the study that is referenced the mostUnfortunately, labetalol, the one drug that anesthesiologists use the most, had never been shown to provide perioperative or for that matter...anytime at all myocardial protection.

The data supports use of beta selective beta blockers..(alpha effects are no good)....so propranolol, metoprolol, bisoprolol, atenolol..

there is actually association between alpha blockade and CHF...ALLHAT trial.

I think it only makes sense that we use some kind of sympatholytic in the perioperative setting....period of high catecholamine state....we always treat pain...why don't we always treat the high catecholamine state?

Hey Mil,

What is it about bisoprolol that you prefer over other beta-blocking agents? Surely the end effect is similar regardless of the drug. Is there a specific effect that you noticed? Peace

 

[Mman]

oops

 

[Mman]

The literature on this one is kind of up in the air. There is pretty good evidence that in high risk patients undergoing high risk operations that beta blockade improves outcomes. There is pretty good evidence that in low risk patients undergoing low risk operations that outcomes are worse with beta blockade (increased bradycardia and hypotension requiring treatment).

Huge middle ground, though, which is where most patients fall.

This is an interesting meta-analysis

The other problem with all the literature about perioperative beta blockade in non-cardiac surgery is the huge number of variables between trials such as beta blocker used, length of treatment, and time of treatment I mean you've got the bisoprolol study looking at very high risk patients (abnormal dobutamine stress echos undergoing vascular surgery) who started bisoprolol up to 30 days prior to surgery on 1 end of the spectrum. Then you've got other studies that only look at beta blocker use post-op in the hospital and not continued as an outpatient.

There just is not a clear cut answer right now for the big middle ground of intermediate risk patients and intermediate risk operations IMHO. I tend to think the current literature is leaning towards benefit for them, however.

 

[Psai]

I was looking through old threads and found this one while trying to figure out if labetalol has any positive long term benefit. All I found was a few small studies from the 80s that talk about how it decreases blood pressure and maybe helps with ci but different people react differently. The major trial since this thread that I can think of is poise where they found decreased nonfatal mi but increased risk of stroke and mortality.

So basically I would continue beta blockers on the day of surgery but not start them in the OR except to help with a bloody field. I was wondering what everyone else thought about beta blockers now.

 

[deleted171991]

I was looking through old threads and found this one while trying to figure out if labetalol has any positive long term benefit. All I found was a few small studies from the 80s that talk about how it decreases blood pressure and maybe helps with ci but different people react differently. The major trial since this thread that I can think of is poise where they found decreased nonfatal mi but increased risk of stroke and mortality.

So basically I would continue beta blockers on the day of surgery but not start them in the OR except to help with a bloody field. I was wondering what everyone else thought about beta blockers now.

The current line of thought, AFAIK, is that they should be continued but not started periop, except maybe for high-risk non-cardiac surgeries and patients.

ACC/AHA Release Updated Guideline on Perioperative CV Evaluation and Management of Non-Cardiac Surgery Patients - American College of Cardiology

Management of cardiac risk for noncardiac surgery