Case Three – HealthValueLab

John Doe is a 60-year-old man with knee osteoarthritis who presents to primary care clinic for pre-operative evaluation prior to elective total knee replacement surgery.

Vitals

Vitals
T	98.6 °F Temperature is within normal limits.
P	72 Pulse is within normal limits.
BP	128/78 Blood pressure is elevated due to systolic BP >120. The patient has a known history of hypertension and is on lisinopril 10 mg daily. This blood pressure reading does not meet the goal of <120/<80, but a repeat measurement should be taken before discussing medication changes.
RR	16 Respiratory rate is within normal limits.
O2 Sat	98% on room air Oxygen saturation is within normal limits.
BMI	25.8 kg/m² Elevated BMI is a significant risk factor for osteoarthritis, particularly in weight-bearing joints like the knees. Obesity increases mechanical stress on the joints, accelerating cartilage breakdown and contributing to pain and inflammation.

Typically, patients will trial joint injections (corticosteroid being first-line) prior to surgery. Corticosteroid injections are one of the few treatments with strong evidence supporting their efficacy in reducing inflammation and pain in osteoarthritis patients. However, their effects are usually limited to <3 months and can diminish with repeated use, and they are not a permanent solution. Additionally, there are many other injection options that patients can try (e.g., hyaluronic acid, stem cell, and platelet-rich plasma injections) that may be beneficial to individual patients but have less evidence of efficacy and are often not covered by insurance.

John Doe is a 60-year-old man who presents to primary care clinic for a pre-operative evaluation in anticipation of elective left knee replacement surgery, which is scheduled in two weeks. Mr. Doe is a retired engineer who led an active lifestyle of recreational running and hiking. However, his knee condition has gradually restricted his physical activities and negatively impacted his quality of life, prompting his decision to undergo surgery.

Mr. Doe was initially diagnosed with left knee osteoarthritis five years ago. He describes his knee pain as a dull, aching sensation that has become more persistent and severe over the past several years. Most of the pain is located on the medial aspect of his left knee and is exacerbated by weight-bearing activities such as walking, climbing stairs, and prolonged standing. His first significant episode of knee pain occurred while running five years ago. Initially, the pain was intermittent and manageable with rest and over-the-counter pain medications. However, the frequency and intensity of the pain increased over time, leading to more frequent use of analgesics and difficulty performing daily tasks. In addition to the pain, Mr. Doe also reports occasional edema and stiffness in his left knee, particularly after physical activity.

Mr. Doe denies any recent trauma or injury to the knee, and there are no symptoms of instability, locking, or catching. He has tried a number of conservative treatments, including physical therapy, weight management, joint supplements (glucosamine and chondroitin sulfate), and joint injections (corticosteroids), but these have offered only temporary relief. Given the significant impact on his functional status and the progression of his symptoms, Mr. Doe and his orthopedic surgeon have decided that knee replacement surgery is the best option to improve his mobility and general quality of life.

Review of Systems

General	No fever, chills, or weight loss.
Eyes	No vision changes or eye pain.
Ears, Nose, Throat	No hearing loss, nasal congestion, or sore throat.
Cardiovascular	No chest pain, palpitations, or known heart disease.
Respiratory	No shortness of breath, cough, or wheezing.
Gastrointestinal	No abdominal pain, nausea, vomiting, or changes in bowel habits.
Genitourinary	No dysuria, hematuria, or urinary frequency.
Musculoskeletal	Chronic left knee pain, no other joint pain or swelling.
Neurological	No headaches, dizziness, or weakness.
Skin	No rashes or bruises.
Endocrine	No polyuria, polydipsia, or heat/cold intolerance.
Psychiatric	No depression, anxiety, or sleep disturbances.

Medications and Supplements

Ibuprofen	200 mg as needed for pain
Lisinopril	10 mg daily
Simvastatin	20 mg daily
Multivitamin	Daily
Glucosamine	500 mg capsule daily
Chondroitin sulfate	800 mg capsule daily

Past Medical History

Medical History According to the American Society of Anesthesiologists’ physical status classification system, Mr. Doe is classified as ASA II based on his medical history, which includes well-controlled hypertension and overweight. His systemic diseases are well-controlled with medications, and he has no current signs or symptoms of any acute exacerbations. Mr. Doe also does not experience any significant functional limitations and manages his daily activities independently. With appropriate management and precautions, Mr. Doe’s ASA II classification suggests that he is at moderate risk of complications during and after surgery but is generally considered suitable for knee replacement surgery. This classification impacts his treatment by guiding the selection and timing of preoperative testing, the choice of anesthesia, and the approach to perioperative management.	Hypertension: Diagnosed 10 years ago, well-controlled with lisinopril as above. Hyperlipidemia: Diagnosed 5 years ago, managed with diet, exercise, and simvastatin as above. Bilateral knee osteoarthritis: Chronic, mostly affecting the left knee. Standing knee x-ray six months ago showed bone-on-bone joint space narrowing of the left knee. Though radiographic severity of osteoarthritis does not always correlate with clinical symptoms (and vice versa), x-ray can be helpful to support the diagnosis of osteoarthritis and rule out other potential causes of joint pain (i.e. fracture). Standing films are the most useful and commonly obtained prior to surgical evaluation so as to visualize the degree of joint space narrowing with weight-bearing.
Surgeries	None. No known history of anesthesia complications.
Hospitalizations	None.
Allergies	No known drug allergies.
Screening Tests	Normal colonoscopy at age 50, normal prostate-specific antigen blood test at 50. Given his normal colonoscopy 10 years ago, Mr. Doe is likely due for a repeat colonoscopy for cancer screening this year. This should be scheduled at earliest convenience but need not delay surgery.
Immunizations	Up to date, per patient.
Last Contact	After initial contact with his orthopedic surgeon six months ago and a thorough evaluation, Mr. Doe and his surgeon have decided that knee replacement surgery is the best option to improve symptoms and function.

Family History

Relation	Notes
Father	Deceased at age 75, history of myocardial infarction. No known history of anesthesia complications. Malignant hyperthermia, a very rare but life-threatening complication of certain anesthetics, can occur in people with specific genetic mutations. The most common mutation is in RYR1, a gene coding for the ryanodine receptor calcium-gated ion channels that are essential for muscle contraction. When given inhaled general anesthetics or succinylcholine, these patients may develop uncontrolled muscle contraction and hyperthermia. It is for this reason that ALL patients undergoing anesthesia should be asked about personal or family history of complications. The treatment for malignant hyperthermia is dantrolene.
Mother	Alive, age 85, history of osteoarthritis and type 2 diabetes. No known history of anesthesia complications.
Siblings	One brother, age 65, history of hypertension and hyperlipidemia. No known history of anesthesia complications.
Children	One healthy adult child. No known history of anesthesia complications.
Other Blood Relatives	None living. No known family history of sudden death or bleeding disorders. No known history of anesthesia complications.

Social History

Occupation	Retired engineer who worked for over 35 years in the civil engineering sector. As his knee osteoarthritis worsened, the pain and stiffness limited his ability to walk long distances and stand for extended periods. Mr. Doe found it especially difficult to perform field inspections and site visits, which were integral parts of his job. To accommodate his condition, Mr. Doe transitioned to more office-based tasks towards the end of his career and delegated field responsibilities to junior engineers.
Education	After earning his Bachelor of Science in Civil Engineering, Mr. Doe went on to obtain his Master of Science in Civil Engineering.
Alcohol	Drinks socially, approximately 1-2 drinks per week.
Smoking	Never smoked.
Drugs	Denies ever using.
Caffine	Drinks one to two cups of coffee each morning. Mr. Doe doesn’t consume other caffeinated beverages like energy drinks or soda, and he avoids caffeine in the afternoon and evening to prevent any impact on his sleep.
Diet	Balanced diet with occasional indulgences, focuses on low-sodium and low-fat foods given his history of hypertension and hyperlipidemia.
Exercise	Walks daily for about 30 minutes and can walk up two flights of stairs without getting short of breath or needing a break. A sedentary lifestyle can exacerbate osteoarthritis by leading to muscle weakness, joint stiffness, and increased body weight. Regular physical activity is essential for maintaining joint function and managing weight. Additionally, limited physical activity, along with other lifestyle and genetic factors, can contribute to the development of hypertension and hyperlipidemia. Therefore, encouraging regular exercise and a healthy lifestyle is crucial for preventing and managing these conditions. For older adults, especially those with physical limitations, it is important to assess cardiovascular fitness using METs. This can be done by asking about their daily activities and exercise tolerance. METs (Metabolic Equivalent of Task) is a concept used to quantify the energy expenditure of physical activities and assess cardiovascular fitness. One MET is the energy expended while sitting quietly, equivalent to approximately 3.5 ml of oxygen per kilogram of body weight per minute. Higher MET values indicate greater energy expenditure and cardiovascular demand. Given Mr. Doe’s age and limitations due to knee osteoarthritis, evaluating his cardiovascular fitness through METs can help his healthcare team determine his surgical risk and potential need for further cardiovascular evaluation or intervention prior to his knee surgery. This ensures a holistic approach to his preoperative care, considering both his current fitness level and his chronic health conditions. Mr. Doe engages primarily in light to moderate activities. For instance: Walking at a slow pace (e.g., around the house or short distances): 2-3 METs Performing household chores (e.g., dusting, washing dishes): 2-4 METs Climbing stairs (if able to tolerate the pain): 4-5 METsGenerally, patients who can perform activities requiring 4+ METs without symptoms are considered low risk for preoperative cardiovascular complications. Patients unable to perform activities requiring 4 METs may be at increased risk and require further pre-operative testing (i.e. stress test). Mr. Doe is able to perform activities requiring >4 METs without symptoms.
Hobbies	Used to participate in recreational running and hiking, but his knee condition has limited these activities. Now, he focuses more on walking and light exercises to maintain his fitness.
Stress	Mr. Doe manages stress well but acknowledges that his knee pain and reduced mobility have been sources of frustration and stress in recent years. He practices mindfulness and meditation, which he finds helpful for relaxation. He also enjoys spending time with his family and friends, which provides emotional support and helps alleviate stress. His retirement has given him more time to focus on his hobbies and health, reducing stress load.
Travel	Mr. Doe and his wife love to travel, especially to historical sites and national parks. They have traveled extensively within the United States and have taken several trips to Europe and Asia. Since his knee pain worsened, they have adjusted their travel plans to include more leisurely activities and destinations that are easier to navigate. They enjoy road trips and have a goal to visit all the national parks in the U.S. Mr. Doe ensures he plans his trips carefully to manage his condition, including taking regular breaks and choosing accommodations that are comfortable and accessible. It’s important to consider the optimal timing for knee replacement surgery, balancing the benefits of surgery with the risks associated with his comorbidities. Plan for comprehensive postoperative care, including pain management, rehabilitation, and monitoring for complications.
Sexual	Monogamous with his wife of 28 years.

Physical Exam

Various scoring systems (or “calculators”) have been developed to help standardize pre-operative evaluation and quantify risk of complications. Perhaps the most widely used is the Revised Cardiac Risk Index for Pre-Operative Risk (RCRI), which estimates the risk of cardiac complications following non-cardiac surgery.

This score takes into account the type of surgery, whether the patient has a personal history of ischemic heart disease, congestive heart failure, cerebrovascular disease, or insulin dependence, and the patient’s pre-operative kidney function.

Notably, all surgery carries risk of complications. Even with the lowest possible RCRI score of 0 (which is the score which our patient Mr. Doe would achieve), there is still an estimated of 3.9% risk of a major cardiac event.

Ordering Diagnostics

Order Name

Lab Results

Lab	Result	Normal Range
Complete blood count (CBC)	WBC: 7.3 thousand/mm³ Hemoglobin: 14.5 g/dL Hematocrit: 43.5% for men Platelets: 255 thousand/mm³	WBC: 4-10 thousand/mm³ Hemoglobin: 13.2-16.6 g/dL for men, 11.6-15 g/dL for women Hematocrit: 41-50% for men, 36-44% for women Platelets: 140-370 thousand/mm³
Basic metabolic panel (BMP)	Sodium: 141 mmol/L Potassium: 3.9 mmol/L Chloride: 101 mmol/L Bicarbonate: 24 mmol/L BUN: 10 mg/dL Creatinine: 0.95 mg/dL Glucose: 89 mg/dL	Sodium: 136-145 mmol/L Potassium: 3.5-5.1 mmol/L Chloride: 98-107 mmol/L Bicarbonate: 22-29 mmol/L BUN: 6-20 mg/dL Creatinine: 0.67-1.17 mg/dL Glucose: 70-99 mg/dL
Comprehensive metabolic panel (CMP) A CMP (as opposed to BMP) may be ordered to provide a broad assessment of overall health, including kidney and liver function, electrolyte balance, and glucose levels. Since Mr. Doe has no history of liver issues, the need for a liver enzyme panel (which is part of the CMP and not included in the BMP) is less critical. If there’s no specific indication for evaluating liver function, you might opt for the BMP, which focuses on the essential metabolic functions without the additional liver tests.	Sodium: 141 mmol/L Potassium: 3.9 mmol/L Chloride: 101 mmol/L Bicarbonate: 24 mmol/L BUN: 10 mg/dL Creatinine: 0.95 mg/dL Glucose: 89 mg/dL Calcium: 9.6 mg/dL AST: 35 U/L ALT: 39 U/L Alkaline phosphatase: 109 U/L Total bilirubin: 0.98 mg/dL Total protein: 7 g/dL Albumin: 4.2 g/dL	Sodium: 136-145 mmol/L Potassium: 3.5-5.1 mmol/L Chloride: 98-107 mmol/L Bicarbonate: 22-29 mmol/L BUN: 6-20 mg/dL Creatinine: 0.67-1.17 mg/dL Glucose: 70-99 mg/dL Calcium: 8.5-10.6 mg/dL AST: 0-40 U/L ALT: 0-41 U/L Alkaline phosphatase: 40-129 U/L Total bilirubin: <1.2 mg/dL Total protein: 6-8 g/dL Albumin: 3.5-5.2 g/dL
PT/INR	PT: 12.4 seconds INR: 1.0	PT: 11-13.5 seconds INR: 0.8-1.1
PTT PT/INR and PTT are used to assess bleeding risk and clotting ability, which are crucial in the setting of surgery.	28 seconds	25-35 seconds
ANA	Negative (1:10)	Negative (< 1:40)
Rheumatoid factor (RF)	Negative (10 U/mL)	Negative (< 15 U/mL)
Anti-CCP	Negative (5 U/mL)	Negative (< 20 U/mL)
Anti-Smith	Negative	Negative
Anti-Ro/SSA	Negative	Negative
Anti-La/SSB	Negative	Negative
Anti-dsDNA	Negative	Negative
Anti-Scl-70	Negative	Negative
Anti-Jo-1	Negative	Negative
EBV	Negative	Negative
HIV	Non-reactive	Non-reactive
Hepatitis C antibody	Negative	Negative
HBsAg	Negative	Negative
HBsAb	Positive A positive hepatitis B surface antibody in the absence of surface antigen and core antibody indicates immunity from prior vaccination.	Negative
HBcAb	Negative	Negative
Lyme EIA	Negative	Negative
RPR	Negative	Negative
TSH	3.0 mU/L	0.4-4.5 mU/L
Free T4	1.0 ng/dL	0.8-1.8 ng/dL
T3	120 ng/dL	60-180 ng/dL
AM cortisol level	15 mcg/dL	10-20 mcg/dL
Vitamin D level	33 ng/mL	20-40 ng/mL
Vitamin B12 level	280 pg/mL	160-950 pg/mL
Folate level	15 ng/mL	2.5-20 ng/mL
PSA	2.4 ng/mL	< 2.5 ng/mL for men aged 40-60, < 4.0 ng/mL for men 60+
CEA	0.4 ng/mL	< 2.5 ng/mL
CA-125	6 U/mL	< 35 U/mL

Imaging Results

Image/Procedure	Result
Electrocardiogram (EKG) EKG is not absolutely indicated in this patient with an RCRI score of zero and no symptoms of cardiopulmonary disease. Nonetheless, it is not unreasonable to order given his age, family history of myocardial infarction, and personal history of hypertension and hyperlipidemia (though well-controlled with medication).	Normal sinus rhythm
Chest x-ray Chest x-ray is not indicated for this patient given his lack of cardiopulmonary disease or cardiac or respiratory symptoms. Nonetheless, the risks of chest radiography are relatively low: radiation exposure, incidental findings, and cost.	Normal (no acute findings)
CT chest with contrast	Normal (no acute findings)
Pulmonary function tests (spirometry) Mr. Doe has no history of respiratory disease or symptoms that would require a CT chest or PFTs. In patients aged 50-80 with a significant smoking history (20+ pack years), a one-time low-dose CT scan may be recommended for lung cancer screening. However, Mr. Doe does not have a smoking history.	Normal
Bilateral knee x-ray A bilateral standing knee film is appropriate to order in a patient like Mr. Doe. However, Mr. Doe has already had a standing film six months ago and therefore does not need a repeat image. It is not expected that meaningful structural change would occur.	Bilateral narrowing of the medial tibiofemoral joint space (left worse than right) and narrowing of the lateral tibiofemoral joint space on the left; bilateral medial and lateral osteophytes of the femoral head (left worse than right) with subchondral sclerosis on the left.
Bilateral knee MRI	Decreased cartilage thickness bilaterally with areas of full-thickness loss on the left; bilateral medial and lateral osteophytes of the femoral head (left worse than right)
Bilateral knee CT More advanced knee imaging (such as MRI or CT) is not always needed prior to surgery and certainly is not indicated as part of primary care pre-operative workup.	Bilateral medial and lateral osteophytes of the femoral head (left worse than right) with subchondral sclerosis on the left.
Stress electrocardiogram (stress EKG) A stress EKG is not indicated in this case because of Mr. Doe’s lack of exertional symptoms (i.e. shortness of breath or chest pain with exertion) or personal history of ischemic heat disease. His risk factors for ischemic heart disease (hypertension, hyperlipidemia) are also well-controlled with medication.	Normal (no ischemic changes with adequate exercise)
Echocardiogram	Normal (no acute findings)

How did you do?

You spent a total of $

You ordered AA% of the absolutely indicated tests in this case.

Even though you saved money with your diagnostic strategy, you may have missed important information that could impact patient outcomes.

Orders that are absolutely indicated to manage and treat the clinical scenario:

Labs	Imaging
CBC
BMP
PT/INR
PTT

You ordered BB% of the not indicated but not harmful tests in this case.

Resisting the temptation to order these tests can help to reduce costs for the health system and the patient.

Orders that are not indicated and would not change management but have minimal harm in the clinical scenario:

Labs	Imaging
CMP	EKG
	Chest x-ray
	Bilateral knee x-ray

You ordered CC% of the not indicated and potentially harmful tests in this case.

Avoiding these tests will minimize potential harms (including complications, undue anxiety, and financial toxicity) to the patient.

Orders that should not be done and may harm the patient in the clinical scenario:

Labs	Imaging
ANA	CT chest with contrast
RF	Pulmonary function tests (spirometry)
Anti-CCP	Bilateral knee MRI
Anti-Smith	Bilateral knee CT
Anti-Ro/SSA	Stress EKG
Anti-La/SSB	Echocardiogram
Anti-dsDNA
Anti-Scl-70
Anti-Jo-1
EBV
HIV
Hepatitis C antibody
HBsAg
HBsAb
HBcAb
Lyme EIA
RPR
TSH
Free T4
T3
AM cortisol level
Vitamin D level
Vitamin B12 level
Folate level
PSA
CEA
CA-125

Your cost breakdown:

You spent a total of $XX (cash price).
Our high-value expert spent a total of $5483.26 (cash price).

With a more efficient diagnostic strategy, you could reduce financial toxicity by ZZ% in this case.

Takeaways

Preoperative testing is a critical component of surgical care for identifying potential risks and optimizing patient outcomes. However, not all tests are necessary for every patient, and routine testing can lead to unnecessary interventions, increased costs, and patient anxiety. The American Society of Anesthesiologists (ASA) recommends the use of a targeted testing approach based on individual risk factors rather than a one-size-fits-all approach. Studies have shown that targeted testing—guided by a patient’s history, physical exam, and the specific surgery—can be just as effective, if not more so, than routine testing.

The ASA Physical Status Classification System is a tool used by anesthesiologists to assess and communicate a patient’s pre-anesthesia medical comorbidities. It consists of six categories:

ASA I: A normal healthy patient.
ASA II: A patient with mild systemic disease.
ASA III: A patient with severe systemic disease that is not incapacitating.
ASA IV: A patient with severe systemic disease that is a constant threat to life.
ASA V: A moribund patient who is not expected to survive without the operation.
ASA VI: A declared brain-dead patient whose organs are being removed for donor purposes.

The system helps in evaluating the patient’s overall health status before surgery and predicting perioperative risks.

Making patient-centered, evidence-based decisions while avoiding wasteful or potentially harmful resource use is a key component of providing high-value care. It’s important to recognize that in actual clinical practice, patient presentations and resource utilization are more complex than in theoretical cases. Healthcare providers must take into account each patient’s preferences, goals of care, and unique circumstances. The objective is not to match the minimum cost provided in this case, but instead foster a mindset that critically evaluates the necessity and value of each test, procedure, or medication in a patient’s care plan. By focusing on value-based principles, you can help enhance patient care, reduce unnecessary testing, and contribute to more efficient healthcare delivery.

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References

Chen, C. S., Dudley, R. A., Auerbach, A. D., & others. (2015). Preoperative Medical Testing in Medicare Patients Undergoing Cataract Surgery. JAMA, 314(6), 602-604. doi:10.1001/jama.2015.9379

Baker JF, Olave M, Leach W, et al. Corticosteroid Injections for Symptomatic Treatment of Osteoarthritis of the Knee: A Pilot Blinded Randomized Trial. ACR Open Rheumatology. 2023;5(10):529. doi:10.1002/acr2.11596

American Society of Anesthesiologists. (n.d.). ASA Physical Status Classification System. Retrieved June 24, 2024, from https://www.asahq.org/standards-and-practice-parameters/statement-on-asa-physical-status-classification-system

Centre (UK) NG. Guideline summary. In: Preoperative Tests (Update): Routine Preoperative Tests for Elective Surgery. National Institute for Health and Care Excellence (NICE); 2016. Accessed August 9, 2024. https://www.ncbi.nlm.nih.gov/books/NBK367919/

Practice Advisory for Preanesthesia Evaluation: An Updated Report by the American Society of Anesthesiologists Task Force on Preanesthesia Evaluation. Anesthesiology. 2012;116(3):522-538. doi:10.1097/ALN.0b013e31823c1067

What Are METs, and How Are They Calculated? Accessed August 9, 2024. https://www.healthline.com/health/what-are-mets#examples

Czajka S, Krzych ŁJ. Association between self-reported METs and other perioperative cardiorespiratory fitness assessment tools in abdominal surgery—a prospective cross-sectional correlation study. Sci Rep. 2024;14(1):7826. doi:10.1038/s41598-024-56887-5

Metabolic equivalent (MET): Pick the best exercise for longevity. whyiexercise.com. Accessed August 31, 2024. https://www.whyiexercise.com/metabolic-equivalent.html

This case was created by Melanie Chuong (UC San Diego School of Medicine), Emma Williams (UC San Diego School of Medicine), and Dr. Ann Xing (UC San Diego Health).

Disclaimer: This case is intended to be used for educational purposes only. Medical science is continuously evolving, and we try to keep up by reviewing our cases on a regular basis. This case was last reviewed in December 2024. If you notice an error or inconsistency with current guidelines, please let us know through the feedback function.

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General	Well-appearing, in no acute distress.
HEENT	Normocephalic, atraumatic. Pupils are equal, round and reactive to light and accommodation. Extra-ocular motion intact. No scleral icterus or conjunctival injection. Tympanic membranes clear. Oropharynx clear. Supple, no lymphadenopathy or thyromegaly.
Cardiovascular	Normal S1 and S2. Regular rate and rhythm, no murmurs, rubs, or gallops. Peripheral pulses 2+ and equal bilaterally.
Respiratory	Clear to auscultation bilaterally, no wheezes, rales, or rhonchi.
Abdominal	Soft, non-tender, non-distended. Normoactive bowel sounds.
Neurological	Alert and oriented to person, place, and time. Cranial nerves II-XII intact. Strength 5/5 in all extremities. Reflexes 2+ and equal bilaterally. Sensation intact.
Skin	No rashes, lesions, or bruising.
Musculoskeletal	Left knee: Tenderness to palpation along the medial joint line, limited range of motion due to pain, mild effusion, no erythema or warmth. Baker’s cyst noted. Other joints: No swelling, erythema, or deformities.