Internal Medicine

Although an uncommon cause for syncope, providers must consider a neurological cause in every patient presenting with transient loss of consciousness. In the absence of signs or symptoms concerning for neurological causes of syncope (such as but not limited to focal neurological deficits), the utility of neuro-imaging studies are of limited benefit. Despite a lack of evidence for the diagnostic utility of neuroimaging in patients presenting with true syncope, providers continue to perform brain computed tomographic (CT) scans. Thus, inappropriate use of this diagnostic imaging modality carries high costs and subject patients to the risks of radiation exposure.

Sources:

Alboni P, et al. Diagnostic value of history in patients with syncope with or without heart disease. J Am Coll Cardiol. 2001 Jun 1;37(7):1921-8. PMID: 11401133.

Grossman SA, et al. The yield of head CT in syncope: A pilot study. Intern Emerg Med. 2007 Mar;2(1):46-9. PMID: 17551685.

Mendu ML, et al. Yield of diagnostic tests in evaluating syncopal episodes in older patients. Arch Intern Med. 2009 Jul 27;169(14):1299-305. PMID: 19636031.

Strickberger SA, et al. AHA/ACCF scientific statement on the evaluation of syncope: From the American Heart Association councils on clinical cardiology, cardiovascular nursing, cardiovascular disease in the young, and stroke, and the quality of care and outcomes research interdisciplinary working group; and the American College of Cardiology Foundation: In collaboration with the Heart Rhythm Society: Endorsed by the American Autonomic Society. Circulation. 2006 Jan 17;113(2):316-27. PMID: 16418451.

Sheldon RS, et al. Standardized approaches to the investigation of syncope: Canadian cardiovascular society position paper. Can J Cardiol. 2011 Mar-Apr;27(2):246-53. PMID: 21459273.

Schnipper JL, et al. Diagnostic yield and utility of neurovascular ultrasonography in the evaluation of patients with syncope. Mayo Clin Proc. 2005 Apr;80(4):480-8. PMID: 15819284.

Task Force for the Diagnosis and Management of Syncope, et al. Guidelines for the diagnosis and management of syncope (version 2009). Eur Heart J. 2009 Nov;30(21):2631-71. PMID: 19713422.

Use of urinary catheters without an acceptable indication of use increases the likelihood of infection leading to greater morbidity and health care costs. Catheter-associated bacteriuria often leads to inappropriate antimicrobial use and secondary complications including emergence of antimicrobial-resistant organisms and infection with clostridium difficile. A previous study showed that physicians are often unaware of urinary catheterization among their patients. Use of urinary catheters has found to be inappropriate in up to 50% of cases, with urinary incontinence listed as the most common reason for inappropriate and continued placement of urinary catheters. Clinical practice guidelines support the removal or avoidance of unnecessary urinary catheters in order to reduce the risk of catheter-associated urinary tract infections (CAUTIs).

Sources:

Bartlett JG. A call to arms: The imperative for antimicrobial stewardship. Clin Infect Dis. 2011 Aug;53 Suppl 1:S4-7. PMID: 21795727.

Gardam MA, et al. Overutilization of indwelling urinary catheters and the development of nosocomial urinary tract infections. Clin Perform Qual Health Care. 1998 Jul-Sep;6(3):99-102. PMID: 10182561.

Hooton TM, et al. Diagnosis, prevention, and treatment of catheter-associated urinary tract infection in adults: 2009 international clinical practice guidelines from the Infectious Diseases Society of America. Clin Infect Dis. 2010 Mar 1;50(5):625-63. PMID: 20175247.

Jain P, et al. Overuse of the indwelling urinary tract catheter in hospitalized medical patients. Arch Intern Med. 1995 Jul 10;155(13):1425-9. PMID: 7794092.

Peleg AY, et al. Hospital-acquired infections due to gram-negative bacteria. N Engl J Med. 2010 May 13;362(19):1804-13. PMID: 20463340.

Saint S, et al. Are physicians aware of which of their patients have indwelling urinary catheters? Am J Med. 2000 Oct 15;109(6):476-80. PMID: 11042237.

Related Resources:

Toolkit: Lose the Tube – A toolkit for appropriate use of urinary catheters in hospitals

Indications for blood transfusion depend on clinical assessment and are also guided by the etiology of the anemia. No single laboratory measurement or physiologic parameter can predict the need for blood transfusion. Transfusions are associated with increased morbidity and mortality in high-risk hospitalized inpatients. Adverse events range from mild to severe, including allergic reactions, acute hemolytic reactions, anaphylaxis, transfusion related acute lung injury, transfusion associated circulatory overload, and sepsis. Studies of transfusion strategies among multiple patient populations suggest that a restrictive approach is associated with improved outcomes.

Sources:

Bracey AW, et al. Lowering the hemoglobin threshold for transfusion in coronary artery bypass procedures: Effect on patient outcome. Transfusion. 1999 Oct;39(10):1070-7. PMID: 10532600.

Carson JL, et al. Transfusion thresholds and other strategies for guiding allogeneic red blood cell transfusion. Cochrane Database Syst Rev. 2012 Apr 18;4:CD002042. PMID: 22513904.

Hebert PC, et al. A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care. Transfusion requirements in critical care investigators, Canadian Critical Care Trials Group. N Engl J Med. 1999 Feb 11;340(6):409-17. PMID: 10318985.

Marik PE, et al. Efficacy of red blood cell transfusion in the critically ill: A systematic review of the literature. Crit Care Med. 2008 Sep;36(9):2667-74. PMID: 18679112.

Villanueva C, et al. Transfusion strategies for acute upper gastrointestinal bleeding. N Engl J Med. 2013 Jan 3;368(1):11-21. PMID: 26013300.

Related Resources:

Toolkit: Why Give Two When One Will Do – A toolkit for reducing unnecessary red blood cell transfusions in hospitals

Repetitive inpatient blood testing occurs frequently and is associated with adverse consequences for the hospitalized patient such as iatrogenic anemia, and pain. A Canadian study showed significant hemoglobin reductions as a result of phlebotomy. Given that anemia in hospital patients is associated with increased length of stay, readmission rates and transfusion requirements, reducing unnecessary testing may improve outcomes. Studies support the safe reduction of repetitive laboratory testing without negative effects on adverse events, readmission rates, critical care utilization or mortality. Laboratory reduction interventions have also reported significant cost savings.

Sources:

Attali M, et al. A cost-effective method for reducing the volume of laboratory tests in a university-associated teaching hospital. Mt Sinai J Med. 2006 Sep;73(5):787-94. PMID: 17008940.

Lin RJ, et al. Anemia in general medical inpatients prolongs length of stay and increases 30-day unplanned readmission rate. South Med J. 2013 May;106(5):316-20. PMID: 23644640.

Smoller BR, et al. Phlebotomy for diagnostic laboratory tests in adults. Pattern of use and effect on transfusion requirements. N Engl J Med. 1986 May 8;314(19):1233-5. PMID: 3702919.

Thavendiranathan P, et al. Do blood tests cause anemia in hospitalized patients? The effect of diagnostic phlebotomy on hemoglobin and hematocrit levels. J Gen Intern Med. 2005 Jun;20(6):520-4. PMID: 15987327.

Routine preoperative tests for low risk surgeries results in unnecessary delays, potential distress for patients and significant cost for the health care system.  Numerous studies and guidelines outline lack of evidence for benefit in routine preoperative testing (e.g., chest X-ray, echocardiogram) in low risk surgical patients.  Economic analyses suggest significant potential cost savings from implementation of guidelines.

Sources:

Benarroch-Gampel J, et al. Preoperative laboratory testing in patients undergoing elective, low-risk ambulatory surgery. Ann Surg. 2012 Sep;256(3):518-28. PMID: 22868362.

Chee YL, et al. Guidelines on the assessment of bleeding risk prior to surgery or invasive procedures. British Committee for Standards in Haematology. Br J Haematol. 2008 Mar;140(5):496-504. PMID: 18275427.

Chung F, et al. Elimination of preoperative testing in ambulatory surgery. Anesth Analg. 2009 Feb;108(2):467-75. PMID: 19151274.

Fleisher LA, et al. 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. J Am Coll Cardiol. 2007 Oct 23;50(17):e159-241. PMID: 19713422.

Fritsch G, et al. Abnormal pre-operative tests, pathologic findings of medical history, and their predictive value for perioperative complications. Acta Anaesthesiol Scand. 2012 Mar;56(3):339-50. PMID: 22188223.

Institute of Health Economics. Routine preoperative tests – are they necessary? [Internet]. 2007 May [cited 2014 Feb 10].

May TA, et al. Reducing unnecessary inpatient laboratory testing in a teaching hospital. Am J Clin Pathol. 2006 Aug;126(2):200-6. PMID: 16891194.

National Institute for Clinical Excellence. Preoperative tests: The use of routine preoperative tests for elective surgery [Internet]. 2003 Jun [cited 2014 Feb 10].

Related Resources:

Patient Pamphlet: Chest X-rays Before Surgery: When you need them and when you don’t

Patient Pamphlet: Echocardiogram Before Surgery: When you need it and when you don’t

Patient Pamphlet: Heart Tests Before Surgery: When you need an imaging test and when you don’t

Several non-opioid therapies (including both drug and non-drug alternatives) may achieve a similar magnitude of improvement in pain and function more safely without the potentially serious side effects of opioid therapy (e.g. harms related to dependence, addiction and overdose).

Source:

Busse JW, et al. Guideline for opioid therapy and chronic noncancer pain. CMAJ. 2017 May 8;189(18):E659-E666. PMID: 28483845.

Thrombophilia testing is costly and can result in harm to patients if the duration of anticoagulation is inappropriately prolonged or if patients are incorrectly labeled as thrombophilic. Thrombophilia testing does not change the management of VTEs occurring in the setting of major transient VTE risk factors. When VTE occurs in the setting of pregnancy or hormonal therapy, or when there is a strong family history plus a major transient risk factor, the role of thrombophilia testing is complex and patients and clinicians are advised to seek guidance from an expert in VTE.

Sources:

Gupta A, et al. Thrombophilia Testing in Provoked Venous Thromboembolism: A Teachable Moment. JAMA Intern Med. 2017 Aug 1;177(8):1195-1196. PMID: 28586816.

Chong LY, et al. Management of venous thromboembolic diseases and the role of thrombophilia testing: summary of NICE guidance. BMJ. 2012 Jun 27;344:e3979. PMID: 22740565.

Patients and their families often prefer to avoid invasive or overly aggressive life-sustaining measures at the end of life. However, many dying patients receive non-beneficial life-sustaining treatments, in part due to clinicians’ failures to elicit patients’ preferences, provide appropriate recommendations, and participate in shared decision-making.

Sources:

Cardona-Morrell M, et al. Non-beneficial treatments in hospital at the end of life: a systematic review on extent of the problem. Int J Qual Healthcare. 2016 Sep; 28(4):456–469. PMID: 27353273.

Downar J, et al. Nonbeneficial treatment Canada: definitions, causes, and potential solutions from the perspective of healthcare practitioners. Crit Care Med. 2015 Feb;43(2):270-81. PMID: 25377017.

Performing percutaneous coronary intervention in the absence of a clear indication is costly and exposes patients to procedural risks, radiation, contrast exposure, and possible stent-related complications. Patients whose symptoms are controlled on optimal medical therapy, and who do not have any high-risk findings* on non-invasive testing (e.g., exercise treadmill test, myocardial perfusion imaging, stress echocardiography, or coronary computed tomographic angiography), should not be referred for percutaneous coronary intervention.

*This table outlines high-risk features of non-invasive test results associated with >3% annual rate of death or MI.

Sources:

Mancini GB, et al. Canadian Cardiovascular Society Guidelines for the Diagnosis and Management of Stable Ischemic Heart Disease. Can J Cardiol. 2014 Aug;30(8):837–849. PMID: 25064578.

Boden WE, et al. Optimal medical therapy with or without PCI for stable coronary disease. N Engl J Med. 2007 Apr 12;356(15):1503-16. PMID: 17387127.

Al-Lamee R et al. Percutaneous coronary intervention in stable angina (ORBITA): a double-blind, randomised controlled trial. Lancet. 2018 Jan 6;391(10115):31–40. PMID: 29103656.

Published guidelines provide clear indications for the use of telemetric monitoring which are contingent upon frequency, severity, duration and conditions under which the symptoms occur. Inappropriate use of telemetric monitoring is likely to increase the cost of care and restrict patient mobility. False positive alarms increase workload and interruptions for front-line clinicians and can create unnecessary anxiety for patients.

Sources:

Benjamin EM, et al. Impact of cardiac telemetry on patient safety and cost. Am J Manag Care. 2013 Jun 1;19(6):e225-32. PMID: 23844751.

Kansara P, et al. Potential of missing life-threatening arrhythmias after limiting the use of cardiac telemetry. JAMA Intern Med. 2015 Aug;175(8):1416–1418. PMID: 26076004.

Sandau KE, et al. Update to Practice Standards for Electrocardiographic Monitoring in Hospital Settings: A Scientific Statement From the American Heart Association. Circulation. 2017 Nov 7;136(19):e273-e344. PMID: 28974521.

Many individuals are erroneously assigned a diagnosis of COPD/asthma without objective diagnostic testing. It is recommended that confirmatory testing be used to make the diagnosis of airflow obstruction in patients with respiratory symptoms. Starting long-term maintenance treatments without first objectively diagnosing COPD/asthma results in unnecessary treatment in those patients who do not actually have the disease. This exposes these patients to both the side-effects and the cost of these medications, and might delay the appropriate diagnosis.

Sources:

Lougheed MD, et al. Canadian Thoracic Society 2012 guideline update: Diagnosis and management of asthma in preschoolers, children and adults: Executive summary. Can Respir J. 2012 Nov-Dec;19(6):e81-8. PMID: 23248807.

Qaseem A, et al. Diagnosis and management of stable chronic obstructive pulmonary disease: a clinical practice guideline update from the American College of Physicians, American College of Chest Physicians, American Thoracic Society, and European Respiratory Society. Ann Intern Med. 2011 Aug 2;155(3):179-91. PMID: 21810710.

Collins BF, et al. Factors predictive of airflow obstruction among veterans with presumed empirical diagnosis and treatment of COPD. Chest. 2015 Feb;147(2):369-376. PMID: 25079684.

Aaron SD, et al. Overdiagnosis of asthma in obese and nonobese adults. CMAJ. 2008 Nov 18;179(11):1121-31. PMID: 19015563.

Aaron SD, et al. Reevaluation of Diagnosis in Adults With Physician-Diagnosed Asthma. JAMA. 2017 Jan 17;317(3):269-279. PMID: 28114551.

Gershon A, et al. Cardiovascular safety of inhaled long-acting bronchodilators in individuals with chronic obstructive pulmonary disease. JAMA Intern Med. 2013 Jul 8;173(13):1175-85. PMID: 23689820.

Joo MJ, et al. Inhaled corticosteroids and risk of pneumonia in newly diagnosed COPD. Respir Med. 2010 Feb;104(2):246-52. PMID: 19879745.

There is emerging evidence that conditions traditionally treated with prolonged courses of IV antibiotics, such as osteomyelitis or infective endocarditis, can safely be treated with PO antibiotics after a lead in period of IV therapy. Studies from the UK estimated that oral antibiotics have a carbon footprint up to 90% lower than the IV equivalent, depending on the antibiotic – a one-week course of oral ciprofloxacin is associated with 1.4kg CO2e (6.8km by car) of emissions versus 100.1kg CO2e (485.9km by car) for intravenous ciprofloxacin. The same group ran an early oral antimicrobial step-down project which saved 300,000 British pounds (or ~$450,000 CAD) annually. Among patients on IV antibiotics, early transition to oral antibiotics has the additional co-benefits of reducing hospital length of stay, length of treatment, nursing care needs, in addition to lowering carbon footprint.

a) All kgCO2e to km conversions in these recommendations are based on a carbon footprint conversion factor of 206gCO2e/km for the average Canadian vehicle in 2017. From: International Energy Agency. Fuel Economy in Major Car Markets: Technology and Policy Drivers 2005-2017. March 2019.

Sources:

Health Quality Ontario. Criteria for Switching From Intravenous to Oral Antibiotics in Patients Hospitalized With Community Acquired Pneumonia: A Rapid Review. 2013.

Harvey EJ, Hand K, Weston D, Ashiru-Oredope D. Development of National Antimicrobial Intravenous-to-Oral Switch Criteria and Decision Aid. J Clin Med. 2023;12(6). PMID: 36983089.

Iversen K, Ihlemann N, Gill SU, Madsen T, Elming H, Jensen KT, et al. Partial Oral versus Intravenous Antibiotic Treatment of Endocarditis. New England Journal of Medicine. 2018;380(5):415-24. PMID: 30152252.

Li H-K, Rombach I, Zambellas R, Walker AS, McNally MA, Atkins BL, et al. Oral versus Intravenous Antibiotics for Bone and Joint Infection. New England Journal of Medicine. 2019;380(5):425-36. PMID: 30699315.

Walpole S, Elii M, Aldridge C. Medicines are responsible for 22% of the NHS’s Carbon Footprint: How do the footprints of intravenous and oral antibiotics compare? Federation of Infection Societies Conference; Manchester 2021.

Specialty societies support the use of oral anticoagulation as initial therapy for many disease states. Evidence also suggests that patients prefer oral anticoagulants over subcutaneous formulations (most commonly, heparinoids) as the oral route is considered easier, less painful and less expensive. Heparinoids are also a highly carbon-intensive medication. The only Health Canada approved source of heparin is porcine mucosa; heparin cannot be synthesized artificially. Approximately 1.1 billion pigs are raised each year to meet the worldwide demand for heparin. It is estimated that 1 kg of intestinal mucosa will produce 160–260 mg of crude heparin. The carbon footprint of raising a heparin swine to maturity is 6.1kg CO2e (30km by car) per kg of pig which amounts to 668 million tonnes CO2e annually (over 3 trillion km by car). Heparin swine are raised in tightly regulated and highly specific conditions with regards to antibiotic and growth hormone usage and cannot be used for dietary pork consumption. The environmental impact associated with processing, manufacturing, transport, and packaging is unpublished but add to heparin’s substantive carbon footprint.

Sources:

Etxeandia-Ikobaltzeta I, et al. Patient values and preferences regarding VTE disease: a systematic review to inform American Society of Hematology guidelines. Blood Adv. 2020 Mar 10;4(5):953-968. PMID: 32150612.

Fan BE, Favaloro EJ. Counting the carbon cost of heparin: an evolving tragedy of the commons? The Lancet Haematology. 2022;9(7):e469-e71. PMID: 35688174.

Ortel TL, et al; American Society of Hematology 2020 guidelines for management of venous thromboembolism: treatment of deep vein thrombosis and pulmonary embolism. Blood Adv 2020; 4 (19): 4693–4738. PMID: 33007077.

Product monograph: Fragmin®. Pfizer Canada. October 2018. p23.

Product monograph: Lovenox®. Sanofi-Aventis Canada. p24. September 2018.

Product monograph: Innohep®. LEO Pharma Inc. May 2017. p26.

Thrombosis Canada. Clinical Guides: DOACs.

Thomas LO, et al.  American Society of Hematology 2020 guidelines for management of venous thromboembolism: treatment of deep vein thrombosis and pulmonary embolism. Blood Adv. 2020; vol. 4, no 19: p. 4693–4738. PMID: 33007077.

van der Meer JY, Kellenbach E, van den Bos LJ. From Farm to Pharma: An Overview of Industrial Heparin Manufacturing Methods. Molecules. 2017 Jun 21;22(6):1025. PMID: 28635655.

MDIs contain hydrofluoroalkane, a potent greenhouse gas that expels the active ingredient from the inhaler device. Based on the type and volume of propellant used, an MDI produces between 9.7kg CO2e (47.1km by car) and 34.8kg CO2e (168.9 km by car). Dried powder inhalers (DPIs) and soft-mist inhalers (SMIs) lack propellant and are significantly less carbon intensive (<1kg CO2e or 5 km by car). Patients consider the environmental impact of their device to be an important consideration when choosing an inhaler device.

Sources:

Gupta S, Couillard S, Digby G, Tse SM, Green S, Aceron R, et al. Canadian Thoracic Society Position Statement on Climate Change and Choice of Inhalers for Patients with Respiratory Disease. Canadian Journal of Respiratory, Critical Care, and Sleep Medicine. 2023;7(5):232-9.

Metting EI, Dijk LV, Messlaki HE, Luers J, Kock J. Development of a shared decision-making tool to support patients and their healthcare provider in choosing the best inhaler device. European Respiratory Journal. 2018:52(suppl.62);OA1643.

Panigone S, Sandri F, Ferri R, Volpato A, Nudo E, Nicolini G. Environmental impact of inhalers for respiratory diseases: decreasing the carbon footprint while preserving patient-tailored treatment. BMJ open respiratory research. 2020;7(1). PMID: 32238349.

Quantz D, Wong GYC, Liang K. Patient perspective on the environmental impact of inhalers: A survey in British Columbia. Canadian Pharmacists Journal. 2023:156(6):298. PMID: 38024456.

Stoynova V, Culley C, Liang K, Chang B. CASCADES (Creating a Sustainable Canadian Healthcare System in a Climate Crisis). Detailed Inhaler Comparison Chart v 2.0.

Interventions that do not align with patient goals produce needless environmental impacts. Ensuring that care setting aligns with a patient’s goals of care can have an important impact on the carbon footprint of a hospital admission. An acute care unit (ward bed) generates 5.5kg of solid waste and 45kg CO2e (218 km by car) per hospital day, as compared to 7.1kg of solid waste and 138 kg CO2e (670 km by car) in an intensive care unit. By integrating routine cognitive and frailty screening for older patients (a low carbon, high value clinical intervention), internists can unmask dementia and discuss the risks of frailty with patients and caregivers which leads to more patients choosing conservative care better aligned with their prognosis and goals, and stands to reduce acute care days.

Sources:

Prasad PA, Joshi D, Lighter J, Agins J, Allen R, Collins M, et al. Environmental footprint of regular and intensive inpatient care in a large US hospital. The International Journal of Life Cycle Assessment. 2022;27(1):38-49.

Varley PR, Buchanan D, Bilderback A, Wisniewski MK, Johanning J, Nelson JB, et al. Association of Routine Preoperative Frailty Assessment With 1-Year Postoperative Mortality. JAMA Surgery. 2023;158(5):475-83. PMID: 36811872.