Preoperative care
Preoperative care is defined as "Care given during the period prior to undergoing surgery when psychological and physical preparations are made according to the special needs of the individual patient. This period spans the time between admission to the hospital to the time the surgery begins."[1][2]
Components of preoperative care
Cardiac risk reduction
Clinical practice guidelines
Clinical practice guidelines[3] by the American College of Cardiology (ACC) and American Heart Association (AHA) recommend (as summarized by Journal Watch:[4][5]
- 'Noninvasive stress testing of patients with 3 or more clinical risk factors and poor functional capacity (less than 4 metabolic equivalents METs) who require vascular surgery is reasonable if it will change management"[3]
- "Patients scheduled for low-risk noncardiac surgery should proceed to surgery."[4]
- "Patients with good functional capacity should proceed to surgery."[4]
- "Patients with poor or unknown functional capacity who are scheduled for non-low-risk surgery should be stratified according to the Revised Cardiac Risk Index[4] (Journal Watch Sep 17 1999). Patients with no risk factors should proceed to surgery. For those with one or more risk factors, clinicians are given the option of proceeding with surgery or performing noninvasive stress testing; the decision should be influenced by the type of noncardiac surgery (vascular vs. other), and by whether the clinician believes that noninvasive testing "will change management."
- "For patients with risk factors, clinicians should consider perioperative ß-blockade."[4]
- "The algorithm does not apply to patients who require emergency noncardiac surgery, or to patients with active cardiac problems." Active cardiac conditions are:[6]
- Unstable coronary syndromes
- Decompensated heart failure (NYHA functional class IV; worsening or new-onset HF)
- Significant arrhythmias
- Severe valvular disease such as severe aortic valve stenosis (mean pressure gradient greater than 40 mm Hg, aortic valve area less than 1.0 cm2, or symptomatic) and symptomatic mitral stenosis
Assessment
Self reported poor functional capacity, defined as inability to walk 4 blocks and climb 2 flights of stairs, increases the risk of cardiac complications in non-cardiac surgery from 5.2% to 9.6%.[7] The accuracy of this question is:
Sensitivity | Specificity | |
---|---|---|
Any serious complication | 71% | 47% |
Serious cardiac complication | 70% | 45% |
- Revised Cardiac Risk Index
The Revised Cardiac Risk Index (RCRI) can help estimate probability of cardiac complications.
- Eagle criteria
The Eagle criteria (Q waves, history of ventricular ectopic activity, diabetes, advanced age, angina) can help assess risk in combination with stress testing.[8] Eagle et al propose that stress testing is most appropriate for patients with one or two of the five criteria. Myocardial revascularization before vascular surgery may help patients with at least 3 Eagle criteria.[9]
- Stress testing
Dobutamine echocardiography stress testing may be the most sensitive non-invasive test.[10] Dobutamine echocardiography has been used to indicate patients who might benefit from perioperative beta-blockers.[11][12]
- Risk by type of surgery
Cardiac risk stratification for noncardiac surgeries From AHA Guidelines, Table 4.[3] See also Figure 1 of Lee et al.[13]
Vascular surgery Aorta, Peripheral vascular surgery Intermediate risk Intraperitoneal and intrathoracic surgery, Carotid endarterectomy, Head and neck surgery, Orthopedic surgery, Prostate surgery Low risk Endoscopic procedures, Superficial procedure, Cataract surgery, Breast surgery, Ambulatory surgery |
Interventions
Perioperative ß-blockade
A meta-analysis of randomized controlled trials found that beta-blockers may cause a decrease in myocardial ischemia (number needed to treat = 16) with a lesser increase in non-fatal strokes (number needed to harm [NNH] = 293).[14] This meta-analysis found significant benefit on overall mortality for patients at high surgical risk (see yellow box for definition of risk categories) but there was no relationship to medical risk categories. The meta-analysis did not regress outcome by mortality in the control groups.
POISE trial[15] 2008 |
DIPOM[16] 2006 |
MaVS[17] 2006 |
DECREASE Study[11] 1999 |
MSPI study[18][19] 1996 | |
---|---|---|---|---|---|
Study characteristics | |||||
Total patients | 8351 | 921 (all had diabetes mellitus) |
496 | 173 (all had positive results on dobutamine echocardiography stress test) |
200 |
Proportion of patients undergoing vascular surgery |
42% | 7% | 100% | 100% | 41% |
Risk of bias according to the Cochrane Collaboration bias scale[20] as assigned by Bangalore et al.[14] | low | low | low | high (control patients did not receive placebo although outcome assessors were blinded) |
low |
Beta-blocker dose | Intravenous metoprolol tartrate followed by oral metoprolol succinate 200 mg/day | Oral metoprolol succinate 100 mg before surgery then 50-100 mg per day | Preoperative < 2 hours, postoperative < 2 hours, and daily metoprolol tartrate(?) based on patient's weight | Bisoprolol 5 mg/day started at least one week preoperatively (average was 37 days). Increased up to 10 mg/day is pulse > 60 | Atenolol 5 mg to 10 intravenous 30 minutes before surgery 50 to 100 mg/day starting the next day |
Goal pulse rate | 50 to 80 (allowed delayed dosing when pulse 45 to 49) |
> 55 bpm (and SBP > 100 mm Hg) |
> 50 bpm (and SBP > 100 mm Hg) |
50 to 60 (and SBP > 100 mm Hg) |
55 to 65 (and SBP > 100 mm Hg) |
Beta-blocker toxicity (absolute increase over control group) |
6% (bradycardia or hypotension requiring treatment or temporary stopping of metoprolol) |
15% (pulse < 65 bpm or SBP < 100 mm Hg) |
12.7% (introperative hypotension requiring treatment) |
Not reported | 0% (requiring stopping of atenolol) |
Cardiac monitoring | Scheduled | Uncertain | Uncertain | Scheduled | As needed |
Outcomes: short-term mortality | |||||
Beta-blocker group | 3.1% (death at two weeks) |
16% (within 30 days) |
0% (within 30 days) |
3.4% (within 30 days) |
4% (in hospital death) |
Subgroup analyses showed significant benefit: • in vascular surgery • presence of 2 of 7 clinical risk factors (see table of risk factors below) | |||||
Placebo group | 2.3% (death at two weeks) |
16% (within 30 days) |
1.6% (within 30 days) |
17% (within 30 days) |
2% (in hospital death) |
Notes: 1. Metoprolol is the only one of these adrenergic beta-antagonists that is metabolized by cytochrome P-450 2D6 allele. 3-10% of anglos are poor metabolizers of drugs that use the CYP2D6 isoenzyme.[21] As a consequence, metoprolol has more variable effect than bisoprolol.[22] 2. The MSPI study showed reduction in perioperative ischemia[19] and mortality at 6 months to two years[18] |
POISE trial
The largest trial in the meta-analysis was the POISE trial.[23][15] Most participants underwent vascular (42%), intraabdominal (23%), or orthopedic (19%) surgery."
POISE | Revised Cardiac Risk Index | |
---|---|---|
Risk factors in common | • undergoing intrathoracic or intraperitoneal surgery • heart failure • transient ischaemic attack • diabetes mellitus • serum creatinine > 175 μmol/L (2.0 mg/dL) |
• high-risk surgery (intraperitoneal, intrathoracic, or vascular surgery above the inguinal ligaments) • heart failure • cerebrovascular disease • preoperative treatment with insulin • preoperative serum creatinine > 175 μmol/L (2.0 mg/dL) |
Unique factors | • age >70 years • undergoing emergent or urgent surgery |
• ischemic heart disease |
The study drug was controlled-release metoprolol:[23]
- "Administration of the study drug at each dosing time, except during the first 6 hours after surgery, requires a patient to have a heart rate ≥50 beats/min and a systolic blood pressure (SBP) ≥100 mm Hg."
- "Two to 4 hours before surgery, patients will take 100 mg (ie, half a tablet) of the study drug orally. If the patient heart rate is >80 beats/min and their SBP is ≥100 mm Hg during the first 6 hours after surgery, they will take 100 mg of the study drug orally. Patients who do not receive a dose of the study drug during the first 6 hours after surgery will take 100 mg of the study drug orally at 6 hours after surgery. Starting 12 hours after patients receive their first postoperative study drug dose and daily thereafter for 30 days, they will take 200 mg of the study drug orally. If the patients' heart rate is consistently <45 beats/min or their SBP is <100 mm Hg, caregivers will hold the study drug until the patients' heart rate or SBP recovers and will then administer 100 mg of the study drug orally. If the patients' heart rate is consistently between 45 and 49 beats/min and their SBP is >100 mm Hg, they will delay taking the study drug for 12 hours."
- "Patients who are unable to take medications orally will receive the study drug by slow or rapid intravenous infusion every 6 hours until they are able to receive the study drug orally. The slow intravenous infusion consists of 15 mg of the study drug in 25 mL of normal saline infused over a 60-minute period, and patients will have their heart rate and blood pressure checked 10, 30, and 60 minutes after starting the infusion. If the patients' heart rate is <50 beats/min or their SBP is <100 mm Hg, the infusion is stopped and subsequent infusions will consist of 10 mg of the study drug in 25 mL of normal saline infused over a 60-minute period."
- "The rapid intravenous infusion will consist of 5 mg of the study drug infused over 2 minutes. Patients will receive the rapid intravenous infusion every 5 minutes, for a total of 15 mg, as long as their vital signs fulfill the standard heart rate and SBP requirements before each dosing."
primary composite endpoint: (CV death, nonfatal MI, nonfatal cardiac arrest) |
Total mortality | |
---|---|---|
hazard ratio: 0.83, P=0.04 | hazard ratio: 1.33, P=0.03 | |
Metoprolol | 5.8% | 3.1% |
Placebo | 6.9% | 2.3% |
Subgroup analyses showed significant benefit from metoprolol among patients:
- Undergoing undergoing vascular surgery
- With 2 or more of 7 clinical risk factors (see table of risk factors)
These results suggest that the benefits on the primary outcome were outweighed by adverse effects; however, the POISE trial was unique in using metoprolol in an anglo population although 3-10% of anglos are poor metabolizers of drugs such as metopolol that use the CYP2D6 isoenzyme.[21] This affects many antidepressants, metoprolol and other drugs that use this isoenzyme. More information is available at Entrez Gene.[24]
MSPI trial
In the The Multicenter Study of Perioperative Ischemia Research Group (MSPI)[18][19], the patients were similar to the POISE study in that about 40% had vascular surgery. The intervention was 50-100 mg of atenolol per day starting on the first postoperative day and continuing for up to 7 days. However, at 6 months there was a trend for more atenolol patients to still be taking beta-blockers (13.8% versus 8.8%).
In the MSPI, atenolol reduced perioperative ischemia.[19]
Regarding mortality, the MSPI study focused its results on mortality at 6 months to two years. In order to compare to the POISE trial, the hospital death rate in the MSPI study was:[18]
- Atenolol 4% (4/99)
- Placebo 2% (2/101)
DECREASE trial
The DECREASE study found benefit by starting bisoprolol 5-10 mg per day at least one week prior to vascular surgery.[11]
Other large trials
Other large randomized controlled trials using bisoprolol[25], and esmolol as a single bolus before intubation[26] have been published and were included in the meta-analysis of Banglore[14]. All patients in these trials were lower risk as manifested in the low risk of complications in the placebo group. No patient died in either study.
Timing surgery after recent coronary stents
"Noncardiac surgery should be delayed until at least 30 days (and perhaps even 90 days) after placement of bare-metal coronary stents and 1 year after placement of drug-eluting stents."[27][28]
Myocardial revascularization
Options for myocardial revascularization include coronary artery bypass and percutaneous transluminal coronary angioplasty. If revascularization is done, the choice of procedure is guided by whether indications exist for coronary artery bypass, and the risk of bleeding with platelet aggregation inhibitors. For patients who need percutaneous transluminal coronary angioplasty yet are at risk of bleeding with platelet aggregation inhibitors, the American College of Cardiology (ACC) and American Heart Association (AHA) recommend:[3]
- Surgery need within 14-29 days, use balloon angioplasty
- Surgery need within 30-365 days, use bare metal stents
- Surgery need within more than 365 days, use drug eluting stents
- Indications according to practice guidelines
Clinical practice guidelines by the American College of Cardiology (ACC) and American Heart Association (AHA) recommend:[3]
- "Coronary revascularization before noncardiac surgery is useful in patients with stable angina who have significant left main coronary artery stenosis. (Level of Evidence: A)"
- "Coronary revascularization before noncardiac surgery is useful in patients with stable angina who have 3-vessel disease. (Survival benefit is greater when left ventricular ejection fraction is less than 0.50.) (Level of Evidence: A)"
- "Coronary revascularization before noncardiac surgery is useful in patients with stable angina who have 2-vessel disease with significant proximal left anterior descending stenosis and either ejection fraction less than 0.50 or demonstrable ischemia on noninvasive testing. (Level of Evidence: A)"
- "Coronary revascularization before noncardiac surgery is recommended for patients with high-risk unstable angina or non–ST-segment elevation myocardial infarction (MI). (Level of Evidence: A)" (NSTEMI)
- "Coronary revascularization before noncardiac surgery is recommended in patients with acute ST-elevation MI. (Level of Evidence: A)"
- "In patients in whom coronary revascularization with percutaneous coronary intervention (PCI) is appropriate for mitigation of cardiac symptoms and who need elective noncardiac surgery in the subsequent 12 months, a strategy of balloon angioplasty or bare-metal stent placement followed by 4 to 6 weeks of dual-antiplatelet therapy is probably indicated. (Level of Evidence: B)"
- "In patients who have received drug-eluting coronary stents and who must undergo urgent surgical procedures that mandate the discontinuation of thienopyridine therapy, it is reasonable to continue aspirin if at all possible and restart the thienopyridine as soon as possible. (Level of Evidence: C)"
- "The usefulness of preoperative coronary revascularization is not well established in high-risk ischemic patients (eg, abnormal dobutamine stress echocardiogram with at least 5 segments of wall-motion abnormalities). (Level of Evidence: C)"
- "The usefulness of preoperative coronary revascularization is not well established for low-risk ischemic patients with an abnormal dobutamine stress echocardiogram (segments 1 to 4). (Level of Evidence: B)"
- Trials
Trial | Patients | Intervention | Outcome | Result | |
---|---|---|---|---|---|
Intervention | Control | ||||
CARP[9] 2004 |
510 patients | • PTCA: 59% (unknown if stents used • CABG: 41% |
myocardial infarction within 30 days | 12% | 14% |
DECREASE-V Pilot Study[29] 2009 |
101 patients with extensive ischemia during stress testing | • PTCA: 65% (61% used drug eluting stent • CABG: 41% |
cause death or myocardial infarction within 30 days | 35% | 33% |
Two randomized controlled trials address myocardial revascularization before noncardiac surgery.[29][9] However, both were performed prior to the ACC/AHA 2007 Guidelines and do not reflect current standards.[3]
- The Coronary Artery Revascularization Prophylaxis (CARP) trial was associated with a statistically insignificant 2% absolute reduction in perioperative myocardial infarction among patients undergoing major vascular surgery.[9] The benefit, while still statistically insignificant, was greater for high risk patients as defined by at least three Eagle criteria with large defect on stress test. The CARP trial did not report what proportion of their patients receiving percutaneous transluminal coronary angioplasty received stents. The stents that were used were probably not drug eluting as sirolimus eluting stents were first approved in the United States in 2003.[30]
- The DECREASE-V Pilot Study reported a trend towards increased complications with myocardial revascularization; however, this trial used drug eluting stents for severe coronary disease prior to non-cardiac surgery.[29]
Pulmonary risk reduction
Clinical practice guidelines by the American College of Physicians state:[31]
- "All patients undergoing noncardiothoracic surgery should be evaluated for the presence of the following significant risk factors for postoperative pulmonary complications in order to receive pre- and postoperative interventions to reduce pulmonary risk: chronic obstructive pulmonary disease, age older than 60 years, American Society of Anesthesiologists (ASA) class of II or greater, functionally dependent, and congestive heart failure."
- "Patients undergoing the following procedures are at higher risk for postoperative pulmonary complications and should be evaluated for other concomitant risk factors and receive pre- and postoperative interventions to reduce pulmonary complications: prolonged surgery (>3 hours), abdominal surgery, thoracic surgery, neurosurgery, head and neck surgery, vascular surgery, aortic aneurysm repair, emergency surgery, and general anesthesia."
- "A low serum albumin level (<35 g/L) is a powerful marker of increased risk for postoperative pulmonary complications and should be measured in all patients who are clinically suspected of having hypoalbuminemia; measurement should be considered in patients with 1 or more risk factors for perioperative pulmonary complications."
- "All patients who after preoperative evaluation are found to be at higher risk for postoperative pulmonary complications should receive the following postoperative procedures in order to reduce postoperative pulmonary complications: 1) deep breathing exercises or incentive spirometry and 2) selective use of a nasogastric tube (as needed for postoperative nausea or vomiting, inability to tolerate oral intake, or symptomatic abdominal distention)."
- "Preoperative spirometry and chest radiography should not be used routinely for predicting risk for postoperative pulmonary complications."
- "The following procedures should not be used solely for reducing postoperative pulmonary complication risk: 1) right-heart catheterization and 2) total parenteral nutrition or total enteral nutrition (for patients who are malnourished or have low serum albumin levels)."
For patients with asthma, more aggressive clinical practice guidelines by the U.S. National Asthma Education and Prevention Program recommend:[32]
- "Patients who have asthma should have an evaluation before surgery that includes a review of symptoms, medication use (particularly the use of oral systemic corticosteroids for longer than 2 weeks in the past 6 months), and measurement of pulmonary function".
- "If possible, attempts should be made to improve lung function preoperatively (FEV1 or peak expiratory flow rate [PEFR]) to either their predicted values or their personal best level. A short course of oral systemic corticosteroids may be necessary to optimize lung function".
Smoking cessation may reduce pulmonary complications according to the results of a randomized controlled trial.[33]
Incentive spirometry does not clearly help reduce pulmonary complications during the perioperative care after coronary artery bypass grafting according to a meta-analysis of randomized controlled trials by the Cochrane Collaboration. [34]
Hepatic risk reduction
The MELD Score can help predict complications of surgery among patients with cirrhosis.[35] The MELD Score may [36] or may not[37] perform better than the Child-Turcotte-Pugh class.
Anemia
An abnormal hemoglobin level is associated with perioperative complications.[38]The amount of fall in hemoglobin may be more important that the absolute level.[39]
Transfusion likely does not help anemia when the hemoglobin is over 8 g/dL.[40][41]
Chronic anticoagulation
This topic has been reviewed.[42]
A systematic review found anticoagulation with warfarin does not need interruption during minor procedures.[43]
For procedures that need discontinuation of anticoagulation, a cohort study that found that interruption for 5 days or less was generally safe.[44]
For patients needing a low molecular weight heparin bridge, a protocol is available.[45]
Obesity
The management of obese patients has been reviewed.[46]
Benefits of preoperative medical consultation
The benefits of internal medicine consultation are not clear in an observational study[47]; whereas a pseudorandomized trial found benefit from a hospitalist consultation[48] and a non-randomized trial using historical controls found benefit from geriatrics consultation[49].
Unnecessary delays in surgery is associated with increased operative risk.[50]
Preoperative methods for surgical risk reduction
A wide range of methods for avoiding surgical errors, either in the operating room or shortly before surgery, are increasingly in use. One method, long used by the choice of individual surgeons, is becoming more of a standard: when, for example, a procedure could be prepared on either the left or right extremity, the surgeon, or even the patient, may write, with an indelible pen, "cut here" on the appropriate site and "do not cut here" on the contralateral extremity, signing both.
Drawing from aviation methods of risk reduction, there are specific points, such as the induction of anesthesia or the entry into a body cavity, when the team stops and goes through a specific checklist of physiological parameters, equipment readiness, etc. In the discipline of crew resource management, one team member is specifically tasked to ask each structured question, and another member to check the matter and give the answer.
References
- ↑ National Library of Medicine. Preoperative care. Retrieved on 2007-11-21.
- ↑ Jaffer, Amir; Gerald Smetana, Steven Cohn, Barbara Slawski (2009-07-01). "Perioperative Medicine Update". Journal of General Internal Medicine 24 (7): 863-871. DOI:10.1007/s11606-009-0965-1. Retrieved on 2009-06-16. Research Blogging.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 Fleisher LA, Beckman JA, Brown KA, et al (2007). "ACC/AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery: Executive Summary: 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 116 (17): 1971–1996. DOI:10.1161/CIRCULATIONAHA.107.185700. PMID 17901356. Research Blogging.
- ↑ 4.0 4.1 4.2 4.3 4.4 Brett AS (2007-11-20). Guidelines for Perioperative Cardiovascular Evaluation for Patients Considering Noncardiac Surgery. Retrieved on 2007-11-21.
- ↑ Winawer N (2008-08-25). Current Guidelines for Preoperative Management Leave Me Wanting More. Retrieved on 2007-11-21.
- ↑ Fleisher LA, Beckman JA, Brown KA, et al (2007). "ACC/AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery: Executive Summary: 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 116 (17): 1971–1996. PMID 17901356.
- ↑ Reilly DF, McNeely MJ, Doerner D, et al (October 1999). "Self-reported exercise tolerance and the risk of serious perioperative complications". Arch. Intern. Med. 159 (18): 2185–92. PMID 10527296. [e]
- ↑ Eagle KA, Coley CM, Newell JB, et al (June 1989). "Combining clinical and thallium data optimizes preoperative assessment of cardiac risk before major vascular surgery". Ann. Intern. Med. 110 (11): 859–66. PMID 2655519. [e]
- ↑ 9.0 9.1 9.2 9.3 9.4 McFalls EO, Ward HB, Moritz TE, et al (December 2004). "Coronary-artery revascularization before elective major vascular surgery". N. Engl. J. Med. 351 (27): 2795–804. DOI:10.1056/NEJMoa041905. PMID 15625331. Research Blogging.
- ↑ Kertai MD, Boersma E, Bax JJ, et al (November 2003). "A meta-analysis comparing the prognostic accuracy of six diagnostic tests for predicting perioperative cardiac risk in patients undergoing major vascular surgery". Heart 89 (11): 1327–34. PMID 14594892. PMC 1767930. [e]
- ↑ 11.0 11.1 11.2 Poldermans D, Boersma E, Bax JJ, et al (1999). "The effect of bisoprolol on perioperative mortality and myocardial infarction in high-risk patients undergoing vascular surgery. Dutch Echocardiographic Cardiac Risk Evaluation Applying Stress Echocardiography Study Group". N. Engl. J. Med. 341 (24): 1789-94. PMID 10588963. [e]
Cite error: Invalid
<ref>
tag; name "pmid10588963" defined multiple times with different content - ↑ Boersma E, Poldermans D, Bax JJ, et al (April 2001). "Predictors of cardiac events after major vascular surgery: Role of clinical characteristics, dobutamine echocardiography, and beta-blocker therapy". JAMA 285 (14): 1865–73. PMID 11308400. [e]
- ↑ Lee TH, Marcantonio ER, Mangione CM, et al (1999). "Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery". Circulation 100 (10): 1043–9. PMID 10477528. [e]
- ↑ 14.0 14.1 14.2 Bangalore S, Wetterslev J, Pranesh S, Sawhney S, Gluud C, Messerli FH (December 2008). "Perioperative beta blockers in patients having non-cardiac surgery: a meta-analysis". Lancet 372 (9654): 1962–76. DOI:10.1016/S0140-6736(08)61560-3. PMID 19012955. Research Blogging.
- ↑ 15.0 15.1 15.2 (May 2008) "Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery (POISE trial): a randomised controlled trial". Lancet. DOI:10.1016/S0140-6736(08)60601-7. PMID 18479744. Research Blogging.
- ↑ Juul AB, Wetterslev J, Gluud C, et al (June 2006). "Effect of perioperative beta blockade in patients with diabetes undergoing major non-cardiac surgery: randomised placebo controlled, blinded multicentre trial". BMJ 332 (7556): 1482. DOI:10.1136/bmj.332.7556.1482. PMID 16793810. PMC 1482337. Research Blogging.
- ↑ Yang H, Raymer K, Butler R, Parlow J, Roberts R (November 2006). "The effects of perioperative beta-blockade: results of the Metoprolol after Vascular Surgery (MaVS) study, a randomized controlled trial". Am. Heart J. 152 (5): 983–90. DOI:10.1016/j.ahj.2006.07.024. PMID 17070177. Research Blogging.
- ↑ 18.0 18.1 18.2 18.3 Mangano DT, Layug EL, Wallace A, Tateo I (1996). "Effect of atenolol on mortality and cardiovascular morbidity after noncardiac surgery. Multicenter Study of Perioperative Ischemia Research Group". N. Engl. J. Med. 335 (23): 1713-20. PMID 8929262. [e]
- ↑ 19.0 19.1 19.2 19.3 Wallace A, Layug B, Tateo I, et al (January 1998). "Prophylactic atenolol reduces postoperative myocardial ischemia. McSPI Research Group". Anesthesiology 88 (1): 7–17. PMID 9447850. [e]
- ↑ Higgins JPT, Green S (editors). Table 8.5.a: The Cochrane Collaboration's Tool for assessing risk of bias. Cochrane Handbook for Systematic Reviews of Interventions Version 5.0.1 [updated September 2008]. The Cochrane Collaboration, 2008. Available from www.cochrane-handbook.org.
- ↑ 21.0 21.1 Phillips KA, Veenstra DL, Oren E, Lee JK, Sadee W (November 2001). "Potential role of pharmacogenomics in reducing adverse drug reactions: a systematic review". JAMA 286 (18): 2270–9. PMID 11710893. [e]
- ↑ Nozawa T, Taguchi M, Tahara K, et al (November 2005). "Influence of CYP2D6 genotype on metoprolol plasma concentration and beta-adrenergic inhibition during long-term treatment: a comparison with bisoprolol". J. Cardiovasc. Pharmacol. 46 (5): 713–20. PMID 16220080. [e]
- ↑ 23.0 23.1 Devereaux PJ, Yang H, Guyatt GH, et al (2006). "Rationale, design, and organization of the PeriOperative ISchemic Evaluation (POISE) trial: a randomized controlled trial of metoprolol versus placebo in patients undergoing noncardiac surgery". Am. Heart J. 152 (2): 223-30. DOI:10.1016/j.ahj.2006.05.019. PMID 16875901. Research Blogging.
- ↑ Anonymous. Entrez Gene: CYP2D6 cytochrome P450, family 2, subfamily D, polypeptide 6 [ Homo sapiens ]. National Library of Medicine. Retrieved on 2009-01-03.
- ↑ Zaugg M, Bestmann L, Wacker J, et al (July 2007). "Adrenergic receptor genotype but not perioperative bisoprolol therapy may determine cardiovascular outcome in at-risk patients undergoing surgery with spinal block: the Swiss Beta Blocker in Spinal Anesthesia (BBSA) study: a double-blinded, placebo-controlled, multicenter trial with 1-year follow-up". Anesthesiology 107 (1): 33–44. DOI:10.1097/01.anes.0000267530.62344.a4. PMID 17585213. Research Blogging.
- ↑ Miller DR, Martineau RJ, Wynands JE, Hill J (October 1991). "Bolus administration of esmolol for controlling the haemodynamic response to tracheal intubation: the Canadian Multicentre Trial". Can J Anaesth 38 (7): 849–58. PMID 1683818. [e]
- ↑ Brett AS (2008). Noncardiac Surgery in Patients with Recently Implanted Coronary Stents - Journal Watch (General). Journal Watch (General).
- ↑ Nuttall GA, Brown MJ, Stombaugh JW, et al (October 2008). "Time and cardiac risk of surgery after bare-metal stent percutaneous coronary intervention". Anesthesiology 109 (4): 588–95. DOI:10.1097/ALN.0b013e318186ddf8. PMID 18813036. Research Blogging.
- ↑ 29.0 29.1 29.2 29.3 Poldermans D, Schouten O, Vidakovic R, et al (May 2007). "A clinical randomized trial to evaluate the safety of a noninvasive approach in high-risk patients undergoing major vascular surgery: the DECREASE-V Pilot Study". J. Am. Coll. Cardiol. 49 (17): 1763–9. DOI:10.1016/j.jacc.2006.11.052. PMID 17466225. Research Blogging.
- ↑ Anonymous (2003). Devices@FDA. Food and Drug Administration. Retrieved on 2009-05-02.
- ↑ Qaseem A, Snow V, Fitterman N, et al (2006). "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. 144 (8): 575–80. PMID 16618955. [e]
- ↑ NHLBI, Diagnosis and Management of Asthma. National Heart, Lung, Blood Institute. Retrieved on 2008-01-24.
- ↑ Møller AM, Villebro N, Pedersen T, Tønnesen H (2002). "Effect of preoperative smoking intervention on postoperative complications: a randomised clinical trial". Lancet 359 (9301): 114–7. PMID 11809253. [e]
- ↑ Freitas ER, Soares BG, Cardoso JR, Atallah AN (2007). "Incentive spirometry for preventing pulmonary complications after coronary artery bypass graft". Cochrane Database Syst Rev (3): CD004466. DOI:10.1002/14651858.CD004466.pub2. PMID 17636760. Research Blogging.
- ↑ Teh SH, Nagorney DM, Stevens SR, et al (April 2007). "Risk factors for mortality after surgery in patients with cirrhosis". Gastroenterology 132 (4): 1261–9. DOI:10.1053/j.gastro.2007.01.040. PMID 17408652. Research Blogging.
- ↑ Farnsworth N, Fagan SP, Berger DH, Awad SS (November 2004). "Child-Turcotte-Pugh versus MELD score as a predictor of outcome after elective and emergent surgery in cirrhotic patients". Am. J. Surg. 188 (5): 580–3. DOI:10.1016/j.amjsurg.2004.07.034. PMID 15546574. Research Blogging.
- ↑ Suman A, Barnes DS, Zein NN, Levinthal GN, Connor JT, Carey WD (August 2004). "Predicting outcome after cardiac surgery in patients with cirrhosis: a comparison of Child-Pugh and MELD scores". Clin. Gastroenterol. Hepatol. 2 (8): 719–23. PMID 15290666. [e]
- ↑ Wu WC, Schifftner TL, Henderson WG, et al (June 2007). "Preoperative hematocrit levels and postoperative outcomes in older patients undergoing noncardiac surgery". JAMA 297 (22): 2481–8. DOI:10.1001/jama.297.22.2481. PMID 17565082. Research Blogging.
- ↑ Karkouti K, Wijeysundera DN, Yau TM, McCluskey SA, van Rensburg A, Beattie WS (April 2008). "The influence of baseline hemoglobin concentration on tolerance of anemia in cardiac surgery". Transfusion 48 (4): 666–72. DOI:10.1111/j.1537-2995.2007.01590.x. PMID 18194382. Research Blogging.
- ↑ Carson JL, Duff A, Berlin JA, et al (January 1998). "Perioperative blood transfusion and postoperative mortality". JAMA 279 (3): 199–205. PMID 9438739. [e]
- ↑ Bracey AW, Radovancevic R, Riggs SA, et al (October 1999). "Lowering the hemoglobin threshold for transfusion in coronary artery bypass procedures: effect on patient outcome". Transfusion 39 (10): 1070–7. PMID 10532600. [e]
- ↑ Kearon C, Hirsh J (May 1997). "Management of anticoagulation before and after elective surgery". N. Engl. J. Med. 336 (21): 1506–11. PMID 9154771. [e]
- ↑ Dunn AS, Turpie AG (April 2003). "Perioperative management of patients receiving oral anticoagulants: a systematic review". Arch. Intern. Med. 163 (8): 901–8. DOI:10.1001/archinte.163.8.901. PMID 12719198. Research Blogging.
- ↑ Garcia DA, Regan S, Henault LE, et al (January 2008). "Risk of thromboembolism with short-term interruption of warfarin therapy". Arch. Intern. Med. 168 (1): 63–9. DOI:10.1001/archinternmed.2007.23. PMID 18195197. Research Blogging.
- ↑ Douketis JD, Johnson JA, Turpie AG (June 2004). "Low-molecular-weight heparin as bridging anticoagulation during interruption of warfarin: assessment of a standardized periprocedural anticoagulation regimen". Arch. Intern. Med. 164 (12): 1319–26. DOI:10.1001/archinte.164.12.1319. PMID 15226166. Research Blogging.
- ↑ Poirier P, Alpert MA, Fleisher LA, et al. (June 2009). "Cardiovascular Evaluation and Management of Severely Obese Patients Undergoing Surgery. A Science Advisory From the American Heart Association". Circulation. DOI:10.1161/CIRCULATIONAHA.109.192575. PMID 19528335. Research Blogging.
- ↑ Auerbach AD, Rasic MA, Sehgal N, Ide B, Stone B, Maselli J (2007). "Opportunity missed: medical consultation, resource use, and quality of care of patients undergoing major surgery". Arch. Intern. Med. 167 (21): 2338–44. DOI:10.1001/archinte.167.21.2338. PMID 18039993. Research Blogging.
- ↑ Roy A, Heckman MG, Roy V (2006). "Associations between the hospitalist model of care and quality-of-care-related outcomes in patients undergoing hip fracture surgery". Mayo Clin. Proc. 81 (1): 28-31. PMID 16438475. [e]
- ↑ Fisher AA, Davis MW, Rubenach SE, Sivakumaran S, Smith PN, Budge MM (2006). "Outcomes for older patients with hip fractures: the impact of orthopedic and geriatric medicine cocare". J Orthop Trauma 20 (3): 172-8; discussion 179-80. DOI:10.1097/01.bot.0000202220.88855.16. PMID 16648698. Research Blogging.
- ↑ Shiga T, Wajima Z, Ohe Y (2008). "Is operative delay associated with increased mortality of hip fracture patients? Systematic review, meta-analysis, and meta-regression: [Le delai operatoire est-il associe a une mortalite accrue chez les patients atteints d'une fracture de la hanche ? Synthese systematique, meta-analyse et meta-regression]". Can J Anaesth 55 (3): 146-54. PMID 18310624. [e]