The controversy over perioperative use of beta blockers just won’t go away. We’ve addressed the issue of perioperative beta blocker use in multiple columns (see Patient Safety Tips of the Week for November 20, 2007 “New Evidence Questions Perioperative Beta Blocker Use” and November 4, 2008 “Beta Blockers Take More Hits” and our December 2009 What’s New in the Patient Safety World column “Updated Perioperative Beta Blocker Guidelines”).
After several years in which we pushed for almost universal use of beta blockers perioperatively, publication of the POISE trial significantly changed things. You’ll recall that the POISE trial 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.
But critics of POISE were quick to point out that the dosage and timing of beta blockade in POISE were not reflective of the optimal way to use perioperative beta blockers. Proponents of their use (eg. Poldermans et al 2009) continue to focus on the need for careful titration of dose, timing, specific beta blocker, and issues such as withdrawal of beta blockers. Those critics have argued that beta blockers should be started well in advance of planned surgery and in low doses that are then titrated upward to meet specific heart rate targets. On the other hand, in POISE the beta blockers were started in most cases IV in relatively high doses on the day of surgery.
Now a new look at some observational data (Wallace 2010) suggests that perioperative beta blockade reduces mortality at both 30 days and one year. And that data reinforces that perioperative withdrawal of beta blockers increases mortality. A protocol for perioperative beta blockers was implemented at the San Francisco VAMC in 1998 after some of the early studies had demonstrated a reduction in cardiac events by use of perioperative beta blockers. That protocol has largely remained in place at that medical center since 1998, though physician compliance with it is purely voluntary. So the authors took a retrospective look at the outcomes in surgery there, comparing patients in whom the protocol was followed to those in which it was not. Their database included over 20,000 patients who had almost 40,000 operations. Those patients who had a beta blocker added had significantly reduced 30-day and one-year mortality rates, as did those in whom pre-operative beta blockers were continued. But those in whom beta blockers were withdrawn had significantly increased risks of death at 30 days and one year. The effects were seen in most types of surgery (cardiac and non-cardiac) though there was no reduction in mortality when beta blockers were added or continued in low-risk patients. The average doses of beta blockers in this study were considerably lower than the equivalent doses used in POISE.
But this was not a randomized controlled trial. It was a retrospective analysis of data and occurred at a medical center where it was widely accepted that perioperative beta blockers are a good thing and activities promoting perioperative beta blocker use were continued throughout the study period. And the reasons why a physician might opt not to use beta blockers was not obvious in their data.
The accompanying editorial by Foex and Sear (Foex 2010) also notes that blood pressure may be important. In the Wallace study a systolic arterial pressure of 120 mm Hg was required before the next dose of beta blocker could be given. Foex and Sear also note that there are really no good studies that address how much in advance of surgery beta blockers should be started.
The Wallace paper showed that beta blocker withdrawal almost quadrupled the 30-day mortality rate and almost doubled the 1-year mortality rate. A similar retrospective analysis of patients undergoing arthroplasty (van Klei 2009) had also shown that withdrawal of beta blockers roughly doubled the postoperative MI rate and mortality rate. The editorial accompanying the van Klei study (London 2009) also summarizes multiple prior studies assessing the effect of beta blocker withdrawal perioperatively. These studies confirm the continuation of beta blockers in patients who are already taking them is important. They confirm the 2009 ACCF/AHA Focused Update on Perioperative Beta Blockade’s only remaining Class I recommendation that beta blockers be continued in patients already taking them for angina, arrhythmias, hypertension or other ACC/AHA class I guideline indications.
A very thoughtful article on the physiological rationale for perioperative beta blockers, the studies done and the reasons for the controversy was published by Chopra and colleagues (Chopra 2009) in 2009. They stress that careful attention to both patient risk and beta-blocker profile is critical to the safe and effective implementation of this therapy.
The controversy is not likely to be resolved until a study like POISE is repeated, using the titrated dose approach to perioperative beta blockers.
Poldermans, Don; Schouten, Olaf; van Lier, Felix; Hoeks, Sanne E.; van de Ven, Louis; Stolker, Robert Jan; Fleisher, Lee A. Perioperative Strokes and Beta Blockade. Anesthesiology 2009. 111(5): 940-945, November 2009.
Wallace AW, Au S, Cason BA. Association of the Pattern of Use of Perioperative ß-Blockade and Postoperative Mortality. Anesthesiology 2010; 113(4): 794-805
Foëx P, Sear JW. Challenges of ß-Blockade in Surgical Patients. Anesthesiology 2010; 113(4): 767-771
van Klei WA, Bryson GL., Yang H, Forster AJ. Effect of [beta]-blocker Prescription on the Incidence of Postoperative Myocardial Infarction after Hip and Knee Arthroplasty. Anesthesiology 2009; 111(4): 717-724
Fleisher LA, Beckman JA, Brown KA, et al.for the American College of Cardiology Foundation, American Heart Association Task Force on Practice Guidelines, 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, Society for Vascular Surgery. 2009 ACCF/AHA Focused Update on Perioperative Beta Blockade Incorporated Into the ACC/AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery. J. Am. Coll. Cardiol. 2009, first published on Nov 2, 2009 as doi: doi:10.1016/j.jacc.2009.07.010
London, MJ. Perioperative [beta]-Blockade, Discontinuation, and Complications: Do You Really Know It When You See It? Anesthesiology 2009; 111(4): 690-694
In our July 8, 2008 Patient Safety Tip of the Week “Medical Helicopter Crashes” and our October 2008 What’s New in the Patient Safety World “More Medical Helicopter Crashes” we discussed the “epidemic” of crashes of helicopters and other medical rescue aircraft in the recent past. In 2008, there were 28 deaths of patients and crew members in crashes involving medical emergency flights. Such crashes continue to be problematic. After a lull in 2009, this year there have been 16 deaths so far and the Federal Aviation Administration (FAA) has just released its proposals for improve medical helicopter safety (Flaherty 2010). The FAA plan would require terrain warning systems, operation control centers for larger companies, pre-flight risk analysis particularly for weather, and stricter flight rules whenever crew are on board (current regulations only apply when patients are on board). The FAA does not require some of the recommendations made last year by the NTSB such as use of night-vision goggles or an autopilot to help relieve the workload on pilots during difficult flights (note that the NTSB makes recommendations when it investigates crashes but it is the FAA that is responsible for implementation of rules and regulations).
We have been very critical that the regulatory agencies involved in oversight of the air medical industry have focused too much on proximate causes and ignored root causes (see our Patient Safety Tips of the Week for February 3, 2009 “” and September 1, 2009 “ ”). Proposed solutions to these crashes have always focused on proximate causes and recommendations have come out in favor of mandating night vision goggles, terrain warning systems, better weather information, changes in pilot training, etc.
All these solutions ignore some of the most important root causes. How did we solve the problem of too many catheter-induced urinary tract infections (CAUTI’s)? We asked “Why are we using so many Foley catheters? Are they all necessary?”. And, of course, we found out that many Foley catheters were not necessary and we successfully reduced CAUTI’s by avoiding unnecessary Foley catheters. We need to apply the same reasoning to medical air rescue crashes and ask “Was an air medical evacuation really necessary here or could ground ambulance have been adequate?”. Even the few root cause analyses (RCA’s) we have seen following actual medical helicopter crashes have failed to ask that fundamental question “Was the helicopter transport indicated in the first place?”.
The problem is that the only regulation for the medical evacuation industry is by the FAA (Federal Aviation Administration). There is no regulation at the state or regional level. And the FAA’s expertise is aviation, not healthcare. There is virtually no system in place by which an air transport has to be justified nor any system to review air transports for necessity and appropriateness.
We previously noted a 2006 study done by Dr. Bryan Bledsoe and his colleagues that was a. Using several widely-used injury severity or trauma scores, they showed that almost 2/3 trauma patients brought by helicopter to a trauma center had minor or non-life-threatening injuries and that 25% were discharged from the hospital within 24 hours. Some helicopter services apparently have rates as high as 20% of transported patients being discharged from emergency rooms shortly after arrival ( ). Even in Maryland, where the trauma system is a model and the medical helicopter system a public one, the post-crash hearings revealed that almost half of patients transported by helicopter to trauma centers were released within 24 hours ( ).
Financial considerations (either cutting costs or pursuing profit) often appear as root causes. The same applies to the air medical rescue industry (and we do mean industry). Our September 1, 2009 Patient Safety Tip of the Week “Levin 2010).” discussed the other real root causes of the problem brought out in an excellent series in the Washington Post by Flaherty & Johnson. The most important root cause is money and what has turned into a highly profitable venture. And many consider pushback from the medical rescue industry to be playing a role in the current FAA proposal (
In our Patient Safety Tip of the Week for February 3, 2009 “” we recommended some of the thinking that should go on in planning and implementing a medical rescue and transport to a trauma center. The first responders on the scene need to rapidly determine a number of factors and contact the emergency medical hub. Questions like the following need to be addressed:
The above questions are really subquestions to the main question “What’s the fastest way to get the patient/victim the medical interventions he needs?” and then assessing the risk:benefit ratio of air vs. ground transport.
The trauma center or hospital on the receiving end should be completing the loop and completing some sort of Quality Improvement tool that links the process to outcomes. But can we really expect the receiving hospital or trauma center to jeopardize the business it receives from the air transports? And, of course, there would be pushback from the medical air transport industry itself. There probably should be a more neutral party that does the evaluations. Most states and regions have perinatal task forces that assess the care provided at local hospitals and that provided at the tertiary referral centers. Why can’t there be a similar arrangement for oversight for air transport cases?
Flaherty MP, Johnson J. FAA proposes safety guidelines for emergency medical copters. Washington Post. October 8, 2010
Levin A. Rules on medical copters to tighten. USA Today 10/8/2010
Bledsoe BE. Wesley AK. Eckstein M. Dunn TM. O'Keefe MF. Helicopter scene transport of trauma patients with nonlife-threatening injuries: a meta-analysis. Journal of Trauma-Injury Infection & Critical Care 2006; 60(6):1257-65 http://www.jtrauma.com/pt/re/jtrauma/abstract.00005373-200606000-00015.htm;jsessionid=LzvDYgJNbkdJpBhDDCFtr3VBPJJ6WwQ1bvdXstQHvMNQ7Lk0Mygl!447927974!181195628!8091!-1?index=1&database=ppvovft&results=1&count=10&searchid=1&nav=search
Greene J. Rising Helicopter Crash Deaths Spur Debate Over Proper Use of Air Transport.
Annals of Emergency Medicine 2009; 53: A15-A17 (March 2009)
Dechter G, Jones B. Md. medevac crash raises question about trauma procedures.
The Baltimore Sun. October 1, 2008
Levin A. Medevac industry opposing upgrades wanted by NTSB. USA Today 8/19/2010
In our August 17, 2010 Patient Safety Tip of the Week “” we noted one important condition to think about during the preoperative consultation or preoperative evaluation is obstructive sleep apnea (OSA).
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 “ ” and our July 2010 What’s 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 or STOP-Bang questionnaire, you may need to approach them as likely having OSA even if they have not yet had confirmation by polysomnography.
Two clinical studies just presented at the ANESTHESIOLOGY 2010 conference emphasize the need to identify OSA patients using screening procedures prior to surgery. One study done at the University of Toronto performed either standard nocturnal polysomnograms or portable home sleep studies on over 800 patients prior to anticipated surgery (surgeons and anesthesiologists were not informed of the results of those studies). Incredibly, 536 of the 819 patients enrolled had obstructive sleep apnea. Of those with severe sleep apnea, 85.5% were not diagnosed by surgeons and 47% were not diagnosed by anesthesiologists. Notably 84% of the patients overall had at least one symptom or sign of OSA such as snoring, excess daytime drowsiness, or observe sleep apnea.
In the second study, also from the Toronto group, the STOP-Bang questionnaire and a wristwatch pulse oximeter were used during the preoperative evaluation in 367 patients. Of these 61% were ranked at high risk for OSA using the STOP-Bang questionnaire. The accuracy of the data extracted from the pulse oximeter to detect moderate and severe sleep apnea was strong. The sensitivity to detect moderate and severe obstructive sleep apnea was 92.8 percent and 100 percent. The specificity to predict moderate and severe obstructive sleep apnea was 74.8 percent and 64.6 percent. There was a strong correlation between those scoring high risk on the STOP-Bang and those with an oxygen desaturation index greater than 10 on the wristwatch oximeter and having confirmed obstructive sleep apnea. The authors therefore suggest a screening process of administering the STOP-Bang, followed by the wristwatch pulse oximetry in those scoring as high risk.
Another group (Vasu 2010) just published a retrospective observational study correlating results of the STOP-Bang with surgical complications. They found that 41.5% of 135 patients who scored high risk on the STOP-Bang questionnaire had higher rates of postoperative complications than those who scored low risk (19.6% vs. 1.3%). They did not confirm OSA with polysomnograms so the association here is with the STOP-Bang score rather than confirmed OSA. Nevertheless, the association was strong and applied across a wide range of types of surgery. Using a cutoff of 3 on the STOP-Bang, they found a sensitivity of 91.7% and specificity of 63% for predicting postoperative complications, making the STOP-Bang a very good tool for screening to identify patients at high risk for postoperative complications.
In their discussion, they discuss how anesthesia, sedation, and analgesia may aggravate sleep-disordered breathing. They also note that REM sleep is diminished or absent on the first postoperative night but this is followed by REM rebound during subsequent nights and that REM-associated hypoxemic events may increase 3-fold on the second and third postoperative nights, with associated risk of complications. They further discuss management of suspected OSA in the perioperative period and use of nasal CPAP in preventing complications.
More good evidence that a simple, easy-to-administer tool can be very valuable in preventing complications in patients undergoing surgery.
American Society of Anesthesiologists. Studies Reveal a Need to Identify and Implement a Screening Procedure for Obstructive Sleep Apnea Prior to Surgery. Newswise 10/17/2010
Vasu TS, Doghramji K, Cavallazzi R, et al. Obstructive Sleep Apnea Syndrome and Postoperative Complications: Clinical Use of the STOP-BANG Questionnaire. Arch Otolaryngol Head Neck Surg. 2010; 136(10): 1020-1024
Our June 22, 2010 Patient Safety Tip of the Week “Disclosure and Apology: How to Do It” provided a comprehensive view of the current state of “disclosure and apology” with guidelines on how to approach adverse events with serious outcomes.
Another new resource has become available since that column, IHI’s “Respectful Management of Serious Clinical Adverse Events”. IHI put this white paper together because they were often asked by organizations after a serious adverse event “what do we do?”. The paper contains most of the recommendations we had in our previous column and has several good checklists to help guide organizations in their responses. It also has a very good bibliography.
A few key points in the white paper are worth emphasizing. They highlight the four hallmarks of a strong crisis management response: immediacy, transparency, apology, and accountability. The speed of the response is extremely important. Though you may not have sufficient information immediately to explain all that happened, it is extremely important to the patient and/or family that the response be prompt, visible and honest. Waiting a few days is not acceptable to them. The patient and family have to be the number one focus in such events. That is why every organization should have a process in place for immediate notification of relevant parties and convening of the RCA team after a serious event has occurred. Having a checklist available to aid in that process is very helpful (see our July 24, 2007 Patient Safety Tip of the Week “Serious Incident Response Checklist”) and helps in assigning responsibilities to team members for actions necessary in the investigation. The IHI whitepaper also has another good recommendation: if you have not yet convened your response team for an actual crisis or serious event, do a simulation so that when a real event occurs everyone knows their roles.
A second key point is involvement of top leadership in the whole process. The IHI white paper strongly recommends that the Board and the CEO take highly visible roles, in addition to the clinical leaders of the organization. The CEO and the Board visibility may be very important in conveying to all the sincerity of apology and commitment to transparency.
Above all, a big part of transparency is keeping all parties in the loop. When you commit to a patient/family that you will learn from the event and take steps to make sure events like this don’t happen again, you need to remain engaged with them and update them on your progress on a regular basis. That same commitment should apply to your obligation to your own staff and organization.
Conway J, Federico F, Stewart K, Campbell MJ. Respectful Management of Serious Clinical Adverse Events. IHI Innovations Series 2010. Cambridge, Massachusetts: Institute for Healthcare Improvement; 2010
We have discussed problems with alarms on numerous occasions. In our February 23, 2010 “Alarm Issues in the News Again” we noted that alarm fatigue is a real problem. Just as we see “alert fatigue” when physicians are exposed to too many alerts and reminders during CPOE, “alarm fatigue” refers to the human tendency to begin ignoring alarms when exposed to a constant bombardment by alarms, many of which are false alarms or not clinically important. We noted a study by Siebig and colleagues (Siebig et al 2010) in medical intensive care units that found only 15% of alarms were considered clinically relevant. That article and the accompanying editorial (Blum 2010) call for future research into alarms and suggest development of monitoring algorithms that could monitor multiple physiological parameters simultaneously to identify clinically relevant changes earlier and more reliably. They also suggest using different audible tones to help differentiate various signals indicating problems with the electrodes versus problems with the patient.
Now a new study (Schmid 2010) looked at alarms in 25 consecutive cardiac surgery cases. They noted an average of 1.2 alarms per minute and noted that approximately 80% of the alarms had no therapeutic consequences, a figure remarkably similar to that found in the Siebig study mentioned above. As noted in the title of this article, the “crying wolf” phenomenon may occur when alarm fatigue leads to ignoring critical alarms that do have clinical consequences.
Ignoring alarms is one of our “big three” contributing factors we commonly encounter when doing root cause analyses of events with advere outcomes. But ignoring alarms usually has its own root causes, most important of which is alarm fatigue. Clearly, we need to look at alarms in virtually every clinical venue and critically assess whether the alarms are needed and whether the net effect of the alarms is beneficial or simply a distraction.
Previous Patient Safety Tips of the Week pertaining to alarm-related issues:
March 5, 2007 “Disabled Alarms”
March 26, 2007 “”
April 2, 2007 “”
June 19, 2007 “Unintended Consequences of Technological Solutons”
April 1, 2008 “Pennsylvania PSA’s FMEA on Telemetry Alarm Interventions”
February 23, 2010 “Alarm Issues in the News Again”
March 2, 2010 “Alarm Sensitivity: Early Detection vs. Alarm Fatigue”
Schmid F, Goepfert MS, Kuhnt D, et al. The Wolf Is Crying in the Operating Room: Patient Monitor and Anesthesia Workstation Alarming Patterns during Cardiac Surgery. Anesth Analg 2010; ANE.0b013e3181fcc504; published ahead of print October 21, 2010, doi:10.1213/ANE.0b013e3181fcc504
Siebig S, Kuhls S; Imhoff M, et al. Intensive care unit alarms - How many do we need? Critical Care Medicine 2010; 38(2): 451-456
Blum JM, Tremper KK. Alarms in the intensive care unit: Too much of a good thing is dangerous: Is it time to add some intelligence to alarms?
Critical Care Medicine 2010; 38(2): 702-703