Patient Safety Tip of the Week

August 17, 2010         Preoperative Consultation – Time to Change



For years we have criticized the preoperative consultation (often inappropriately referred to as “medical clearance”) as being nearly useless in the way it is currently done in most places. Similar to the situation for the “annual physical examination”, there is a dearth of evidence to demonstrate any real value of the preoperative consultation in terms of patient outcomes. Now a new study (Wijeysundera et al 2010) actually suggests that the preoperative consultation may cause unintended consequences and actually lead to adverse outcomes. That Canadian group looked at outcomes in patients in Ontario who underwent major elective noncardiac surgery and had a preoperative consultation and compared those outcomes to those of a matched cohort that did not have a preoperative consultation. They found that those having such consultation had higher mortality rates and longer hospital lengths of stay, plus more preoperative testing and pharmacological interventions. Note that the study period was prior to publication of the POISE trial (see our November 20, 2007 Patient Safety Tip of the Week “New Evidence Questions Perioperative Beta Blocker Use” and our November 4, 2008 Patient Safety Tip of the Week “Beta Blockers Take More Hits”), which showed that, though preoperative beta blockers prevented 15 MI’s for every 1000 patients treated, there was an increased risk of stroke and an excess of 8 deaths per 1000 patients treated. The authors of the current study speculate, with some corroborating evidence, that the increased mortality and increased stroke occurrence in the patients having preoperative consultation may have resulted from increased use of beta blockers.


The Canadian study does rely on some assumptions and extrapolations. First response would be to say “Of course they would do worse. It’s the sicker and more high risk patients who get referred for preoperative consultation.”. But the authors used some proxies and sensitivity analyses that suggest this was probably not the case. Their results also persisted after adjustment for a variety of potentially confounding factors and were seen across multiple subgroups studied. The study was restrospective and observational, not a randomized controlled trial. They used a previously validated algorhithm to identify likely preoperative consultations from administrative data. But the authors also admit that they have no idea how many cases might have had surgery cancelled because of the findings during a preoperative consultation.


The Canadian group had previousy done a retrospective cohort study (Wijeysundera et al 2010b) which found that noninvasive stress testing before major non-cardiac surgery was associated with improved one-year survival and shorter mean hospital length of stay. However, when patients were stratified by cardiac risk, the mortality benefit was primarily in those with high risk (Revised Cardiac Risk Index 3-6 points) and to a much lesser degree in those at intermediate risk (RCRI 1-2 points). Furthermore, such testing in those at low risk actually caused harm.


The current study does not suggest that the preoperative consultation should be abandoned. What the above says is that we need to apply the same principles to evaluate the effectiveness of the preoperative consultation that we apply to evaluation of any procedure, drug, etc. We clearly need to determine what aspects of a preoperative consultation are important in influencing patient outcomes.We also clearly need to consider changing the focus of the preoperative consultation. Traditionally, it has been focused on cardiac issues. Regular readers of this newsletter know we stress the preoperative evaluation of risk for other complications like delirium, post-op respiratory depression, etc.


ICSI (Institute for Clinical Systems Improvement) recently put out a guideline “Preoperative Evaluation” that you may find useful. It does note which recommendations are based in evidence and it has some nice preoperative questionnaires and forms. It also has a simple “Patient Preoperative Guide” for patients to use as they prepare for surgery. The history and physical examination, not the laboratory, remain the core of the preoperative consultation. First and foremost, the guideline emphasizes that routine testing should be minimized and that tests ordered should be individualized to the specific medical issues pertinent to each patient. That, of course, is a recommendation we have seen since the mid-1990’s but we are amazed again and again at how many physicians and hospitals ignore that concept and do a whole host of preoperative tests that do not impact on the patient’s outcome. Remember, Joint Commission holds you to comply with whatever your policy says about preoperative testing. So don’t put a whole lot of recommendations in such policy if they are not evidence-grounded.


We also need to think about who should do the preoperative consultation. Historically, it has usually been done by the primary care physician (PCP) or, in the case of patients with a known high risk condition such as coronary artery disease or stage 4 chronic kidney disease, by the specialist. But today many primary care physicians don’t even come to the hospital. Inpatients are often managed or co-managed by hospitalists. So maybe the preoperative consultation might be more appropriately done by the hospitalist, who will be following the patient in the hospital. On the other hand, the PCP needs to be asking him/herself “What will I need to do for this patient after discharge?”. In our April 7, 2009 Patient Safety Tip of the Week “Project RED” and April 14, 2009 Patient Safety Tip of the Week “More on Rehospitalization After Discharge”) we noted  a paper by Jencks et al 2009 that noted 72.6% of hospital 30-day Medicare readmissions in surgical patients are for medical (non-surgical) reasons. Very few of those readmissions had even seen their PCP between discharge and rehospitalization.


Note that co-management is another issue you need to address (see our October 27, 2009 Patient Safety Tip of the Week “Co-Managing Patients: The Good, The Bad, and The Ugly”). If you do co-manage, make sure that everyone knows who will be responsible for which aspects of care.


The timing of the preoperative consultation may also be important. Most such consultations tend to get done in the 1-2 weeks prior to the anticipated surgery. Yet that leaves insufficient time for some interventions, such as smoking cessation, withdrawal of certain medications, titration of beta-blockers in certain (fewer and fewer) patients, or correction of nutrional deficiencies.


Also note that the preoperative consultation is different from the preoperative evaluation done by anesthesiologists. The anesthesiologist needs to utilize much of the information gleaned from the preoperative medical consultation but the focus of the anesthesiologist visit tends to focus on things important for the operation and often fails to pay sufficient attention to other than immediate postoperative management.


There are a whole host of predictors of post-operative complications, some of which are patient-related and some of which are related to they type of surgery being performed. Patient-related factors include advanced age, comorbidities (especially pulmonary, cardiac, and renal), impaired cognitive function, malnutrition, and impairment of functional status. Interestingly obesity, by itself, has not been implicated as a risk factor for complications. However, the comorbidities of obesity, such as sleep apnea, may be significant risk factors. Surgical procedure-related risk factors include urgent or emergency surgery and the type of surgery (eg. cardiac surgery, major abdominal or thoracic surgery, vascular surgery, etc.). There has been conflicting evidence related to the type of anesthesia used but note that our August 2010 What’s New in the Patient Safety World column “SCIP: Disappointing Outcomes on SSI’s. What’s Next?” noted a new population-based study (Chang 2010) showing that patients having total hip or total knee replacement surgery done under general anesthesia were 2.21 times more likely to develop an SSI within 30 days of surgery compared to those done under epidural or spinal anesthesia.


Assessing a patient’s ability to perform activities of daily living or a functional estimate of the MET’s a patient is capable of may predict their vulnerability to surgical complications. And there are a number of validated scoring instruments that are very good at predicting surgical complications and outcomes. These include the ASA score, Lee’s revised cardiac risk index, and the Eagle score. In our June 2010 What’s New in the Patient Safety World colum “The Frailty Index and Surgical Outcomes” we noted a new study (Makary et al 2010) demonstrating use of the frailty index greatly improved the ability to predict post-surgical outcomes much better than existing methods. These may help physicians, patients and families anticipate what to expect in patients undergoing surgery. But our concern is that they lack specific action items. It’s one thing to say “this is a high risk patient”. It’s another to say “this is a risk factor that we can specifically do something about”.


We can’t do better outlining the cardiac portion of the consultation than what is in two recent editorials (Chopra et al 2010, Cheng et al 2010) that we discussed in our February 2010 What’s New in the Patient Safety World column “Preoperative Testing for Non-Cardiac Surgery”. Both suggest that perioperative tests and treatments improve cardiac outcomes only when targeted to clearly defined patient subsets and that clinical trials have shown no additional benefit of cardiac testing in patients at low to moderate risk for perioperative cardiovascular events. They recommend following the American College of Cardiology/American Heart Association Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery. They also note that doing so would reduce perioperative costs considerably.


So let’s focus on some things we clearly can have an impact on. We’ve talked previously about some of the dangers of obstructive sleep apnea (OSA) in the postoperative period and how to screen for them (see our Patient Safety Tips of the Week for June 10, 2008 “Monitoring the Postoperative COPD Patient” and August 18, 2009 “Obstructive Sleep Apnea in the Perioperative Period” and our July 2010 Whats New in the Patient Safety World column “Obstructive Sleep Apnea in the General Inpatient Population”). In patients scoring high on a tool like the STOP, you may need to approach them as likely having OSA even if they have not yet had confirmation by polysomnography.


In addition to sleep apnea, you need to consider whether the patient has any other conditions that may predispose them to respiratory depression when they are being managed with narcotic analgesics postoperatively. Such conditions might be COPD, severe chest wall or spinal deformities, certain neuromuscular disorders, etc. In such circumstances you’ll consider aiming for lower oxygen saturation targets and consider using end-tidal CO2 monitoring for hypercarbia.


The American College of Physicians released a guideline “Risk Assessment for and Strategies To Reduce Perioperative Pulmonary Complications for Patients Undergoing Noncardiothoracic Surgery: A Guideline from the American College of Physicians” in 2006. It stresses risk factors for post-op pulmonary complications, such as age greater than 60, COPD, ASA class II or above, CHF, functional dependence, and numerous characteristics of the surgery itself. A low serum albumin is a particularly strong predictive factor for pulmonary complications. Importantly, it stresses that performance of spirometry or chest x-ray are not routinely indicated preoperatively nor should right heart catheterization or total parenteral nutrition be used. It does recommend use of incentive spirometry or deep breathing exercises or other lung expansion modalities prior to a variety of surgeries.


Smoking cessation is useful not only in minimizing pulmonary complications but also in improving wound healing and reducing the risk of some infectious complications. The greater the interval between smoking cessation and the time of surgery, the better the outcomes.


The patient’s nutritional status needs to be evaluated. The best indicators of this are the BMI, a history of recent weight loss, and the serum albumin. While it would make sense to try to improve the patient’s nutritional status prior to surgery (one of the reasons you’ll want to do the consultation with ample time prior to surgery), the best way to manage that nutritional status and the evidence-based outcomes are not clear at this time.


We’ve also discussed extensively the issue of postoperative delirium (see our October 2008 back-to-back columns “Managing Delirium” and “Preventing Delirium” and our March 31, 2009 Patient Safety Tip of the Week “Screening Patients for Risk of Delirium” and our January 26, 2010 Patient Safety Tip of the Week “Preventing Postoperative Delirium”). The most salient predictors of postoperative delirium are the presence of dementia or disordered executive function. You can screen for these using simple tests like the MMSE or the clock drawing test. Vision or hearing impairment are also risk factors and part of preventing or treating delirium is minimizing these sensory disorders by ensuring the patient has his/her glasses or hearing aid available in the hospital.


If you do identify patients at risk for postoperative delirium, you want to avoid certain drugs (benzodiazepines, anticholinergic agents, diphenhydramine, Demerol, etc.). You would also consider less depth of anesthesia or alternatives to general anesthesia and pay careful attention to minimize preoperative fasting to avoid dehydration and to preferentially use certain opiates. In the postoperative phase, careful attention to reorienting activities, use of familiar objects from home, support of family, promoting natural sleep, adequate pain management, early mobilization, avoiding restraints, etc. are important. Prophylactic use of haloperidol or other agents to prevent development of delirium (or minimize its duration) have produce mixed results.


Reviewing the patient’s medications, including over-the-counter medications and alternative medicines and nutritional supplements, is extremely important. When you do such reviews, you’ll be surprised how often you discover the patient is taking a medication no longer needed (eg. proton pump inhibitors begun prophylactically during a prior hospitalization) or that the patient is on duplicative therapy. So you may end up paring down his/her medication list. You also need to consider whether the patient is  taking any medications (or alcohol) that may lead to withdrawal syndromes during a hospitalization. If the patient is on steroids for COPD or other comorbidity, you’ll need to consider whether using “stress” doses post-op will be necessary. You’ll need to consider specific drugs that should be stopped during certain surgeries (eg. tamsulosin or other alpha blocker in cataract surgery). You’ll need to consider which drugs may promote bleeding and discontinue them prior to surgery if necessary. And you will need to consider what will happen with certain drugs during the period when the patient cannot swallow (for example, some anti-Parkinson’s medications and some anticonvulsants do not have intravenous formulations so alternative ways to ensure these are given must be considered). And in the diabetic patient, discussion of what the insulin needs are likely to be post-op become important. In addition to the drugs you’d like to avoid in a patient at risk for delirium, drugs on Beer’s list (see our January 15, 2008 Patient Safety Tip of the Week  Managing Dangerous Medications in the Elderly ” and June 2008 What’s New in the Patient Safety World “Potentially Inappropriate Medication Use in Elderly Hospitalized Patients”) should generally be avoided in the geriatric patient.


If the patient has chronic kidney disease (CKD), you’ll need to offer advice on dosing of a variety of drugs excreted via the kidneys. Hopefully your hospital has a computerized physician order entry (CPOE) system with good decision support that will help identify those drugs whose dose or dosing interval needs to be adjusted. You’ll also have to consider the possibility that the surgery or other perioperative factors (eg. contrast used during CT scans) may precipitate acute worsening of renal function. And if the patient has more advanced degrees of renal dysfunction, you’ll need to suggest avoiding blood transfusions that might interfere with eventual kidney transplantation or avoiding IV lines, etc. in a limb that may need to be used for dialysis access (Krishnan 2002).


 In addition to planning for discharge and ensuring appropriate medical followup in addition to the surgical followup, you’ll need to consider what venue the patient will likely need on discharge. Particularly in the elderly, bedrest may lead to “deconditioning” and a general decline in functional abilities. Many such patients may need a stay in subacute care after discharge. Others will need in-home nursing services. You’ll have to plan for appropriate medical followup in those venues.


Lastly, don’t forget to discuss advance directives and end-of-life issues during the pre-operative consultation. Many physicians find those sort of issues difficult to broach with patients and families but a preoperative consultation allows a natural segue into that discussion. It’s easy to say something like “We don’t expect you are going to have any serious problems with your surgery, but…” and then ask what the patient’s wishes would be if any such disasters occurred.






Wijeysundera DN, Austin PC, Beattie WS,  Hux JE, Laupacis A.
Outcomes and Processes of Care Related to Preoperative Medical Consultation. Arch Intern Med. 2010; 170(15): 1365-1374



Wijeysundera DN, Beattie WS, Austin PC, Hux JE, Laupacis A. Non-invasive cardiac stress testing before elective major non-cardiac surgery: population based cohort study

BMJ  2010;340:b5526 (Published )



Fleisher LA, Beckman JA, Brown KA, Calkins H, Chaikof E, Fleischmann KE, et al; ACC/AHA Task Force Members. ACC/AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery): Developed in Collaboration With the American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society for Vascular Medicine and Biology, and Society for Vascular Surgery. Circulation. 2007; 116: e418-e500



ICSI (Institute for Clinical Systems Improvement). Preoperative Evaluation (Guideline). Released 06/2010



Jencks SF, Williams MV, Coleman EA.. Rehospitalizations among Patients in the Medicare Fee-for-Service Program. NEJM 2009; 360: 1418-1428



Chang C-C, Lin H-C; Lin H-W, Lin H-C. Anesthetic Management and Surgical Site Infections in Total Hip or Knee Replacement: A Population-based Study. Anesthesiology 2010; 113(2): 279-284 August 2010



Makary MA, Segeve DL, Pronovost PJ, et al. Frailty as a Predictor of Surgical Outcomes in Older Patients. Journal of the American College of Surgeons 2010;

DOI: 10.1016/j.jamcollsurg.2010.01.028


Chopra V, Flanders SA, Froelich JB, Lau WC, Eagle KA. Perioperative Practice: Time to Throttle Back. Annals of Internal Medicine 2009. Published online before print November 30, 2009



Cheng D. Preoperative non-invasive stress testing should be reserved for patients at high risk of perioperative cardiac complications. BMJ 2010; 340: b5401



Fleisher LA, Beckman JA, Brown KA, Calkins H, Chaikof E, Fleischmann KE, et al; ACC/AHA Task Force Members. ACC/AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery): Developed in Collaboration With the American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society for Vascular Medicine and Biology, and Society for Vascular Surgery. Circulation. 2007; 116: e418-e500



Fleischer LA, Beckman JA, Brown KA, et al. ACC/AHA 2006 Guideline Update on Perioperative Cardiovascular Evaluation for Noncardiac Surgery: Focused Update on Perioperative Beta-Blocker Therapy. J Am Coll Cardiol 2006; 47: 2343-2355



Qasseem A, Snow V, Fitterman N, et al. for the Clinical Efficacy Assessment Subcommittee of the American College of Physicians. Risk Assessment for and Strategies To Reduce Perioperative Pulmonary Complications for Patients Undergoing Noncardiothoracic Surgery: A Guideline from the American College of Physicians. Ann Intern Med 2006; 144: 575-580



Krishnan M. Preoperative Care of Patients with Kidney Disease

Am Fam Physician. 2002; 66(8): 1471-1477















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