Perioperative medication management: General principles and practical applications
ABSTRACT
An extensive medication history, including the use of nonprescription agents and herbal products, is the foundation of effective perioperative medication management. Decisions about stopping or continuing medications perioperatively should be based on withdrawal potential, the potential for disease progression if therapy is interrupted, the potential for drug interactions with anesthesia, and the patient’s short-term quality of life. In general, medications with withdrawal potential should be continued perioperatively, nonessential medications that increase surgical risk should be discontinued before surgery, and clinical judgment should be exercised in other cases.
KEY POINTS
- Common drugs that have been associated with withdrawal symptoms when discontinued preoperatively include selective serotonin reuptake inhibitors (SSRIs), beta-blockers, clonidine, statins, and corticosteroids.
- In general, most nonsteroidal anti-inflammatory drugs should be stopped at least 3 days before surgery.
- Although ACE inhibitors and angiotensin receptor blockers intensify the hypotensive effects of anesthesia, it may be prudent to continue them perioperatively unless their only indication is for hypertension and the patient’s blood pressure is well controlled.
- Herbal medications should be stopped at least 7 days before surgery, owing to the uncertainly over their actual contents.
- Among psychotropics, SSRIs, tricyclic antidepressants, benzodiazepines, and antipsychotics are generally safe to continue perioperatively.
CONCLUSIONS
A good medication history that includes herbal and OTC products is essential for safe induction of anesthesia and optimization of outcomes during and following surgery. In general, medications with the potential to induce withdrawal symptoms should be continued. The use of nonessential medications that can increase surgical risk should be discontinued. If neither of these conditions applies, consider the patient’s risk profile and the risk of the procedure when making perioperative management decisions. Be mindful of withdrawal syndromes and resume medications with the potential for such syndromes as soon as possible.
DISCUSSION
Comment from the audience: In regard to your comment that diuretics are typically held on the morning of surgery, my institution recently completed a randomized placebo-controlled trial (publication is pending) in which we studied the effect of continuing or not continuing furosemide preoperatively. We found no difference in the occurrence of intraoperative hypotension between the two groups. It will be interesting to see if these findings change practice over time.
Dr. Whinney: It’s good to know that hypotension is not a concern with furosemide, but the issue here is not just blood pressure but electrolyte abnormalities that could predispose to arrhythmias. The patients who concern me are those who haven’t been seen by a physician for a while and may be on high doses of furosemide. I would scrutinize such patients closely.
Question from the audience: We see a number of patients on methotrexate and other disease-modifying rheumatologic drugs. Can you comment on the perioperative management of these medications?
Dr. Whinney: Methotrexate has caused some anxiety over the risk of infection, but the literature does not support such concern.24 In fact, it appears that continuing methotrexate is probably advisable because the risk of decompensation of the disease may be worse than the potential infectious risks. The only caveat is the patient with renal insufficiency, in whom the recommendation is to withhold methotrexate for 2 weeks before surgery. While most rheumatologists favor withholding disease-modifying drugs perioperatively, a recent systematic review showed no increased risk of either total or infectious complications with use of immunomodulators including infliximab, azathioprine, and cyclosporine.25 It is still reasonable and prudent to discuss this issue with the patient’s rheumatologist. Hydroxychloroquine is safe to continue.
Comment from the audience: First, I would like to urge everyone to be mindful of medication-related indications for preoperative testing. There are many psychotropic drugs that prolong the QT interval and thus constitute an indication for a baseline electrocardiogram prior to surgery. Second, I believe there is a mythology in the perioperative community about the bleeding risk associated with omega-3 fatty acids and vitamin E. Can you comment on the bleeding risks associated with each?
Dr. Whinney: There are few data; the fear is based purely on the potential of these compounds to cause bleeding. Neither is beneficial for short-term quality of life or for chronic prevention, and there’s no withdrawal syndrome from either. So I generally withhold them, but if the patient is still taking them up to the day of surgery, it doesn’t merit postponing surgery. I generally let the surgeon or the nurse know, and it tends not to be a big deal.
Question from the audience: Do you stop herbal teas, energy drinks, and diet medications such as phentermine prior to surgery?
Dr. Whinney: You need to know which diet medications the patient is taking. The problem with many of the OTC products is that they may or may not be considered drugs, so they may not be approved by the FDA and thus you don’t know what the patient is actually taking. For the most part, a diet medication does not contribute to short-term quality of life. My aim is to get the patient through surgery as safely as possible, so if a patient is taking an agent with ingredients, known or unknown, with an interaction potential, then I will stop it.
The two types of diet agents are those that block the absorption of fat, which could interact with other oral agents given at the same time, and those that act via the gastrointestinal tract. I generally withhold the fat-absorption blockers the day before surgery. Phentermine has the potential for catecholinergic reactions or sympathomimetic actions. I would put it in the category of herbal-type medicines and withhold it for at least 7 days.
Question from the audience: Can you comment on combination drugs such as losartan/hydrochlorothiazide on the morning of surgery?
Dr. Whinney: The ARB losartan may have more physiologic benefit than the diuretic, so I would prescribe a single dose of losartan the morning of surgery if I had decided to continue this class of medication for uncontrolled hypertension or concern over heart failure decompensation. The same is true for a beta-blocker/diuretic combination product; I will prescribe the beta-blocker component individually and tell the patient to take it the morning of surgery.
Question from the audience: I’m confused by the recommendation to stop hydrochlorothiazide. It’s a far less potent diuretic than furosemide. Does the risk of stopping it, with resulting blood pressure elevation, outweigh the risk of a mild hypotensive response because of a mild diuretic effect? I’m aware of no data on the risk of stopping hydrochlorothiazide—are you?
Dr. Whinney: There are no data. Again, the recommendation is based on the physiology of the drug, as well as on expert consensus and opinion. Since anesthesia has a vasodilatory effect with a hypotensive response, it’s probably reasonable to hold hydrochlorothiazide if its only indication is for hypertension. That’s the logic behind the recommendation. If you continue it the day of surgery, it may not necessarily hurt, but we’re not certain.
Question from the audience: The implication from your third case study was that alendronate should be held. What’s the basis of that recommendation?
Dr. Whinney: First, the patient has to be upright for 30 minutes after taking alendronate, which could be a problem on the morning of surgery. Also, withholding it will not impair short-term quality of life; it’s a weekly medication, so the patient can take her next dose once she’s up and ambulatory.
Question from the audience: What do you for young women on oral contraceptives? I’m lucky if I see them within 7 days of surgery.
Dr. Whinney: You’re bringing up the concern with exogenous hormones and the risk of venous thromboembolism (VTE), a risk that clearly is increased with the hypercoagulable milieu of surgery. The recommendation is to stop hormone therapy 30 to 45 days prior to surgery in these patients. As you note, however, we don’t get the chance to see patients during that window of opportunity. So the question is whether stopping hormones within a shorter time period results in an incremental benefit. And that is not necessarily the case. These patients should be seen as being at risk for VTE and be given appropriate VTE prophylaxis. In fact, in the similar context of menopausal hormone therapy, a study among women undergoing orthopedic surgery showed that as long as they received appropriate VTE prophylaxis, there was no significant difference in VTE rates between the women whose hormone therapy was withheld versus those who continued it.26
Question from the audience: Are there concerns about withdrawal in patients with peripheral vascular disease treated with cilostazol or pentoxifylline?
Dr. Whinney: It’s not particularly well studied. Guidelines from the American College of Physicians suggest to hold these agents for elective surgeries.27 With respect to antiplatelet therapies, O’Riordan et al did a systematic review of 99 articles pertaining to antiplatelet agents in the perioperative period and concluded that aspirin should not be stopped in patients going for surgery.28 In vascular surgery, antiplatelet agents may help promote graft patency.
