Tag: MLA

You review the electronic health record (EHR) with Dr. Nayar and consider which aspects of the past medical history you will want to obtain from Christina.
Chief Concern: 19-year-old female presenting with right ankle pain.
Problem List:
Otitis Media (age 2)
Mononucleosis (age 14)
Left radial head fracture (age 15)
You refer to the CDC Immunization schedule to identify if Christina is overdue for any immunizations. After reviewing her immunization record, you conclude that she is up to date on all recommended shots.
TEACHING POINT
Past Medical History
All portions of the past medical history including medical problems, surgeries, food and medicine allergies, and social history are important.
Often, the immunization history is overlooked when patients don’t come in expressly for a prevention visit. But, the immunization history is significant, even in an acute visit, as another opportunity to update immunizations may not present itself for a while.
You go to the exam room and introduce yourself to the patient, Christina, and her mother, Mrs. Martinez. You then begin to interview Christina about the mechanism and timing of her ankle injury.
“Can you tell me more about how you hurt your ankle?”
Tearfully, she elaborates, “I was playing soccer last night and was trying to pass the ball to a teammate. Somehow I slipped and fell.”
“Do you know which way you fell on your ankle?”
Christina says, “My ankle really hurts along the outside. I am having a lot of problems walking and it’s a little stiff. It was swollen yesterday.” Mrs. Martinez adds, “I saw her ankle twist inward as she fell to the ground. The coach immediately iced the area and she was able to leave the field under her own power.”
“Have you ever had other difficulties with your ankle?”
“No, this is the first time anything like this has ever happened.”
“Do you have other health concerns you would like to address today?”
“Actually, I have been having problems when I pee, but I want to talk about my ankle first.”
Given this information, you suspect Christina’s injury is probably moderate. You refocus and plan to follow up by asking questions to eliminate concern about a limb-threatening injury.
TEACHING POINT
Significance of Historical Features of Ankle Injury
A patient who seeks help immediately, and is non-weight bearing, is more likely to have a severe injury than one who presents a few days after an incident and is fully weight-bearing (the ability to take four steps independently).
A history of previous ankle sprain is a common risk factor for an ankle injury.
While hearing a snap or tear is diagnostically significant in an acute knee injury, it is not in an acute ankle injury.
Differential of Acute Ankle Pain Following Inversion Injury
Acute ankle injury is one of the most common musculoskeletal injuries in athletes and sedentary persons, accounting for an estimated 2 million injuries per year and 20% of all sports injuries in the United States.
There are many potential reasons for ankle pain.
Achilles tendon rupture
A common sports injury classically associated with an audible “pop.” Incidence increases with age. Patients are unable to plantarflex.
Fibular fracture
Usually due to a fall, an athletic injury, or a high-velocity injury such as a motor vehicle accident. Patient may have severe pain, swelling, inability to ambulate, and deformity. The Ottawa ankle rules help to distinguish patients who need an x-ray to rule out such a fracture.
Lateral ankle sprains
Generally present acutely (after trauma) with pain, warmth, and some swelling. Ankle sprains do not create a deformity. If there is a large amount of swelling present, however, it may appear to be a deformity.
Medial ankle sprain
Somewhat rare and suggests that forced eversion has occurred. There is typically injury to the deltoid ligament.
Osteoarthritis of the ankle
Less common than in some other joints. It is a chronic process, more commonly seen in older people. The tibiotalar joint is generally involved and the condition may occur as a result of prior injury, obesity, or history of rheumatoid disease. Symptoms may include stiffness, swelling, deformity, and a feeling of instability.
Peroneal tendon tear
Typically due to an inversion injury and may occur in conjunction with a lateral ankle sprain. Patient may complain of persistent pain posterior to the lateral malleolus. Swelling may or may not be present. Repetitive trauma may cause injury to the peroneal tendons.
Syndesmotic sprain
Generally involves the interosseous membrane and the anterior inferior tibiofibular ligament. Pain and disability are often out of proportion to the injury. One would expect a positive ankle squeeze test.
Mechanism of Injury and Anatomy of Ankle Sprains
Plantar flexion and inversion
The most common mechanism of injury in ankle sprains is a combination of plantarflexion and inversion. The lateral stabilizing ligaments, which include the anterior talofibular, calcaneofibular, and posterior talofibular ligaments, are most often damaged.
The anterior talofibular ligament is the most easily injured. Concomitant injury to this ligament and the calcaneofibular ligament can result in appreciable instability. The posterior talofibular ligament is the strongest of the lateral complex and is rarely injured in an inversion sprain.
The anterior drawer test can be used to assess the integrity of the anterior talofibular ligament, and the inversion stress test can be used to assess the integrity of the calcaneofibular ligament.
Excessive eversion and dorsiflexion
In medial ankle sprains, the mechanism of injury is excessive eversion and dorsiflexion. Medial ankle stability is provided by the strong deltoid ligament, the anterior tibiofibular ligament, and the bony mortise. Because of the bony articulation between the medial malleolus and the talus, medial ankle sprains are less common than lateral sprains.
Question
What are the signs/symptoms that are included in determining the grade of an ankle sprain?
Select all that apply.
The best options are indicated below. Your selections are indicated by the shaded boxes.
A. Ecchymosis
B. Ligament tear
C. Loss of functional ability
D. Pain
E. Swelling
SUBMIT
Answer Comment
The correct answers are A, B, C, D, E.
All of these elements—in addition to whether the patient can bear weight—are used to grade an ankle sprain. See Teaching Point below.
TEACHING POINT
Grading Ankle Sprains
Grading of ankle sprains takes into consideration:
The presence/absence of a ligament tear
Loss of functional ability
Severity of pain
Presence and/or severity of swelling
Presence of ecchymosis
Difficulty bearing weight: the ability to take four steps independently
Grade I sprain involves stretching and/or a small tear of a ligament. There is mild tenderness and swelling, slight to no functional loss, and no mechanical instability. No excessive stretching or opening of the joint with stress.
Grade II sprain is characterized as an incomplete tear and moderate functional impairment. Symptoms include tenderness over the involved structures, mild to moderate pain, swelling, and ecchymosis. In this grade, there is some loss of motor function and mild to moderate instability. Stretching of the joint with stress, but with a definite stopping point.
Grade III sprain is characterized as a complete tear and loss of integrity of the ligament. Severe swelling (greater than 4 cm about the fibula) and ecchymosis may be present, along with an inability to bear weight and mechanical instability. Significant stretching of the joint with stress, without a definite stopping endpoint.
Please note that clinical grading of lateral ankle sprains may be limited based on a number of factors including patient pain level, interexaminer reliability, and the subjective nature of using visual inspection findings to establish an accurate diagnosis. Initial management amongst each grade of lateral ankle sprains will likely depend more on other factors individualized to a given patient and their symptoms.
The next step you would like to take to work up Christina’s symptoms is to see if you can elicit any costovertebral angle (CVA) tenderness and examine her abdomen. You tap on Christina’s back below the ribs on both sides and elicit no expression of tenderness. She does not have suprapubic tenderness, rebound, or guarding.
Mrs. Martinez wants to know, “What do you think is going on?”
Dr. Nayar asks you,
“So what grade of ankle sprain do you think Christina has?”
You reply, “I am not sure. Christina has some loss of functional ability and pain. She had swelling on the first day, but none now. There isn’t any bruising on exam, but she does not want to weight bear. I’m having trouble deciding between Grades I and II. In the end, I would say Grade I because Christina has persistent pain, previous swelling that has resolved, tenderness, and mild to moderate inability to function.”
He agrees and adds,
“Do you think we should get an x-ray to rule out a fracture?”
“I’m pretty sure she just has a sprain. But Mrs. Martinez was very firm in wanting Christina to have an x-ray. I’m not really sure what the best thing to do is.”
TEACHING POINT
Deciding When Foot/Ankle Radiography Is Indicated – Ottawa Ankle Rules
Ankle injuries are the most common presentation to the emergency department, yet less than 15% of these injuries turn out to be clinically significant fractures.
The Ottawa rules are evidence-based tools developed to help physicians decide when radiography is indicated.

Describe a quality improvement initiative in your current or recent practice setting. What was the nurse’s role in the project? What was the outcome of the project? Has the improvement been sustained?

Assignment Prompt
Early Pregnancy/Obstetrics
A 20 year-old G1P0A0 female presents to your clinic complaining of crampy lower abdominal pain and spotting. She states her last period was 5 weeks ago, she took a home pregnancy test yesterday and it was positive. She states she tried to make an OB appointment but they could not get her in for several weeks. What questions would you ask this patient? Describe how you would assess and treat this patient using evidence-based practice. Submissions should be in APA format and should include an introduction/conclusion. Review the rubric carefully before submitting.
Expectations
Research: Citations required
Length: 500 words, not including references
Citations: At least two high-level scholarly references in APA from within the last 5 years

Discussion Prompt
Contraception
A 17 year-old sexually active female presents to your clinic and reports that she is interested in starting birth control. Briefly discuss at least THREE birth control options and be sure to mention the pros/cons/indications/contraindications for each method.
Expectations
Initial Post:
Length: A minimum of 275 words, not including references
Citations: At least one high-level scholarly reference in APA from within the last 5 years

Discussion Prompt
Telemedicine
Reflect on your experience with using telemedicine. (If you have not used telemedicine discuss the benefits and how it can improve patient outcomes.) How did telemedicine change the access of care to the patient being cared for?
Resources
Medicare Fact Sheet:
https://www.cms.gov/newsroom/fact-sheets/medicare-telemedicine-health-care-provider-fact-sheet
Telehealth Implications:
https://www.npjournal.org/article/S1555-4155(17)30808-5/pdf
Telehealth Billing:
https://drive.google.com/file/d/1lRkSkxSCls26hfGyBDIWZiO7NQE8crVx/view
Expectations
Initial Post:
Length: A minimum of 275 words, not including references
Citations: At least one high-level scholarly reference in APA from within the last 5 years

Discuss Evidence bbased practice relating to Prostatic Hyperplasia and Constipation related to age
identify 3 barriers to quality of care
1.access to health care due to advanced age
2. transportation services
3. Dietary choices and access
How can you adress these barriers

Attend a unit management meeting and analyze the effectiveness of leadership.
Utilize the leadership skills and management functions inherent in organizational, interpersonal, and group communication.
Assess the effectiveness of the meeting and leader.
Criteria Ratings
PAPER (70%)
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Fails to identify a relevant research topic or is not clearly defined and/or the paper lacks focus throughout.
Satisfactory (75-79)
Identifies a topic but may be too broad in scope and/or the paper is somewhat unclear and needs to be developed further. Focal point is not consistently maintained throughout the paper.
Good (80-89)
Identifies a relevant topic and paper provides adequate direction for the paper with some degree of interest for the reader. The paper states the position, premise, or hypothesis, and is the focal point of the paper for the most part.
Excellent (90-100)
Identifies a relevant research topic and a thesis that provides direction for the paper that is engaging and thought provoking. The paper clearly and concisely states the position, premise, or hypothesis and is consistent with the focal point throughout the paper.
Content (40%)
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Satisfactory (75-79)
Information provides minimal support for the topic. Reader shows very little insight.
Good (80-89)
Information provides reasonable support for topic and displays evidence of a basic analysis of a significant topic. Reader gains some insights
Excellent (90-100)
Balanced presentation of relevant and legitimate information that clearly supports a central purpose or argument and shows a thoughtful, in-depth analysis of a significant topic. Reader gains important insights.
Data Collection Techniques & Use of Data (15%)
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An explanation of data collection techniques is not present. A description of how data collected from interview will be used is not present.
Satisfactory (75-79)
An explanation of data collection techniques is included but lacks supporting details. A description of how data collected from interview will be used is included but lacks supporting details.
Good (80-89)
An explanation of data collection techniques is complete and includes supporting details. A description of how data collected from the interview will be used is complete and includes supporting details.
Excellent (90-100)
An explanation of data collection techniques is extremely thorough and includes substantial supporting details. A description of how data collected from the interview will be used is extremely thorough and includes substantial supporting details.
ORGANIZATION AND EFFECTIVENESS (15%)
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Paper is clear and forecasts the development of the paper. Paper is descriptive and reflective of the topic and appropriate to the purpose.
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Paper is comprehensive and contains the essence of the topic. Introductory statement makes the purpose of the paper clear.
Logic and Construction (5%)
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Paper is not justified by the conclusion. The conclusion does not support the purpose. Paper is incoherent and uses noncredible sources.
Satisfactory (75-79)
Techniques of research are minimally evident. The transition of progression throughout the paper is not smooth and choppy.
Good (80-89)
Techniques of research are evident. There is a smooth progression of format from introduction to conclusion.
Excellent (90-100)
Clear and convincing detail that presents a persuasive claim in a distinctive and compelling manner.
Mechanics of Writing (includes spelling, punctuation, grammar, language use) (5%)
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Surface errors are pervasive enough that they impede communication of meaning. Inappropriate word choice or sentence construction is used.
Satisfactory (75-79)
Mechanical errors are very evident and numerous typos are present and distracting to the reader. Sentence structures are incomplete.
Good (80-89)
Some mechanical errors or typos are present, but they are not overly distracting to the reader. Correct sentence structure and audience-appropriate language are used.
Excellent (90-100)
Writer is clearly in command of standard, written, academic English.
FORMAT (15%)
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APA 7 is not used appropriately, or format is rarely followed correctly.
Satisfactory (75-79)
APA 7 is minimally evident. There are multiple formatting errors.
Good (80-89)
APA 7 is used, and formatting is correct, although some minor errors may be present
Excellent (90-100)
All APA 7 formats elements are correct.
Documentation of Sources (citations, footnotes, references, bibliography, etc., as appropriate to assignment and style) (10%)
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Sources are not documented.
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Sources are documented, as appropriate to assignment and style, although some formatting errors may be present.
Good (80-89)
Sources are documented, as appropriate to assignment and style, and format is mostly correct.
Excellent (90-100)
All sources are documented appropriately. Formatting is correct.

You are working at a family medicine clinic with Dr. Hill. She tells you, “The next patient, Mr. Smith, is a 53-year-old male with a chief concern of swelling and pain in his left lower extremity.”
Before you go to see Mr. Smith, a quick review of the chart reveals that he has type 2 diabetes, obesity, hypertension, and hyperlipidemia. You note that he has not been to the office in the past six months, and it appears that he should be out of all of his medications.
When you enter the examination room, Mr. Smith, a middle-aged male, greets you from where he is sitting. You introduce yourself and ask him what brings him to the office today.
He replies, “It’s my left leg. The past four days it has been red, swollen, and painful—and it seems to be getting worse.”
You ask him to tell you more about this problem.
He says, “It began several days ago, and the swelling seems to be getting worse. It hurts all the time; it doesn’t even get better when I rest it. It seems to get a little worse when I move around. It hurts to walk as soon as I try to stand on it.”
Now that you have a general sense of Mr. Smith’s issue, you ask more focused questions.
“Did you do anything to injure your foot?”
He replies, “I do not remember any injury, but there has been this sore on the bottom of my foot for several months. There’s nothing draining out of the sore and it doesn’t hurt, although my foot doesn’t have much feeling in it.”
“Before this happened, were you sitting down for a long time without getting up and using your legs, such as taking a long airplane trip; or have you been on bed rest?”
“I wish I could go somewhere on an airplane and get a good vacation, but I can’t afford anything like that. I haven’t been on bed rest. I’ve been pretty busy lately.”
“When was the last time you were in the office?”
“It has been a long time now because my daughter and new baby recently moved in with me and I have been trying to take care of the baby as well as keep my job as a bus driver,” he explains.
“Have you been taking your medication?”
He replies, “I have been out of my medication for several weeks now.”
After talking with Mr. Smith more, you discover:
Social History: Does not drink alcohol, but does smoke 1.5 packs of cigarettes daily, he is unmarried, and lives in public housing with his three children and one grandchild.
Review of Systems: No fever or chills, no chest pain, no shortness of breath, and no swelling of the right leg.
You examine Mr. Smith and find:
Vital Signs: T 36.5 °C (97.8 °F), BP 140/90, HR 85, RR 12, O2 98%
Cardiovascular and lung exam: Unremarkable
Lower extremity exam:
Mr. Smith’s entire left leg is swollen, warm and erythematous. The measurement of the circumference of the largest left calf section is 3.5 cm larger than his right calf at the same location.
There is pitting edema. The leg is tender to the touch, especially along the distribution of the deep venous system.
Dorsalis pedis and posterior tibialis pulses are palpable on both feet. Digital capillary refill time is two seconds. Deep tendon reflexes are present (2+).
He has decreased sensation and is unable to determine the location of a monofilament test on either foot up to the ankle in a stocking distribution.
You note a 2 cm ulceration on the plantar surface of Mr. Smith’s left foot.
At this point, you excuse yourself to discuss your findings with Dr. Hill, assuring Mr. Smith you will return in a few moments.
Dr. Hill asks you to consider a differential diagnosis.
Choose five of the following that are at the top of your differential given what you know of Mr. Smith so far.
The best options are indicated below. Your selections are indicated by the shaded boxes.
A. Cellulitis
B. Deep venous thrombosis
C. Lymphedema
D. Muscle strain
E. Peripheral artery disease
F. Popliteal cyst
G. Venous insufficiency
SUBMIT
Answer Comment
The correct answers are A, B, C, E, G.
Most Likely Diagnoses
Mr. Smith’s concern of swelling that is unilateral is an important finding to support the diagnosis of cellulitis, lymphedema, or deep vein thrombosis (DVT). In contrast, for venous insufficiency one would expect bilateral leg swelling. Peripheral artery disease (PAD) is not particularly associated with edema.
Cellulitis and DVT are acute processes. Lymphedema, PAD, and venous insufficiency are less likely, given the acute nature of Mr. Smith’s symptoms.
Since PAD, venous insufficiency, and lymphedema are not infectious processes, the lack of fever in Mr. Smith’s case keeps these diagnoses on the differential.
In Mr. Smith’s case, the acute unilateral swelling, erythema, and warmth in a diabetic patient, make cellulitis (A) likely. The presence of a fever would support the diagnosis of an infectious process like cellulitis. But the fact that Mr. Smith does not have a fever doesn’t rule out a diagnosis of cellulitis as it is certainly possible to have localized cellulitis without fever.
In Mr. Smith’s case, you feel that the acute nature of his symptoms—the unilateral swelling, and the presence of risk factors such as obesity, smoking, and diabetes—make DVT (B) a very likely diagnosis. Mr. Smith does not have a fever, but the inflammatory process due to a thrombus in his vein could explain his unilateral lower extremity edema.
Lymphedema (C) can be present unilaterally, however this is usually a more chronically developing problem, making this diagnosis less likely.
While venous insufficiency (G) could contribute to the development of a DVT, the acute and unilateral nature of Mr. Smith’s symptoms make you think a diagnosis of venous insufficiency alone is less likely.
In Mr. Smith’s case, a diagnosis of PAD (E) seems unlikely given the lack of claudication and normal pulses on examination. Although PAD may not be the primary cause of Mr. Smith’s leg swelling and pain, it could potentially be contributing to it by increasing his risk for a foot ulcer. Mr. Smith’s history of smoking and diabetes increases the likelihood that he has PAD.
Less Likely Diagnoses
Muscle strain (D)—Although this can be a cause of swelling and pain, in a patient with intact mental status, a history of trauma should be present to consider this.
Popliteal cyst (F)—This should be palpable behind the knee and rarely would cause the extensive swelling and pain seen in Mr. Smith.
TEACHING POINT
Differential of Unilateral Lower Extremity Edema
Most Likely Diagnoses
Lymphedema
Lymphedema is generally painless, but patients may experience a chronic dull, heavy sensation in the leg. In the early stages of lymphedema, the edema is soft and pits easily with pressure. In the chronic stages, the limb has a woody texture and the tissues become indurated and fibrotic.
Lymphedema initially involves the foot and gradually progresses up the leg so that the entire limb becomes edematous.
Cellulitis
Cellulitis is an acute inflammatory condition of the skin characterized by localized pain, erythema, swelling, and heat.
Small breaks of skin are associated with streptococcal infection, whereas staphylococcal cellulitis is commonly associated with larger wounds, ulcers, or abscesses.
Patients with diabetes are more susceptible to infections like cellulitis. Diabetic neuropathy causes an unawareness of abnormal pressure distribution. Ill-fitting shoes, cuts, or punctures can then lead to the development of ulcers.
Vascular disease with diminished blood supply contributes to the development of the lesion, and infection is common.
DVT
Classic symptoms of DVT include swelling, pain, and discoloration in the affected extremity.
Physical examination may reveal the palpable cord of a thrombosed vein, unilateral edema, warmth, and superficial venous dilation.
Classic signs of DVT include Homan’s sign (pain on passive dorsiflexion of the foot), edema, tenderness, and warmth. While difficult to ignore, they are of low predictive value and can occur in other conditions such as musculoskeletal injury, cellulitis, and venous insufficiency.
Chronic venous insufficiency may result from DVT and/or valvular incompetence. Following DVT, the valve leaflets become thickened and contracted so that they are incapable of preventing retrograde flow of blood; the vein becomes rigid and thick-walled. Although most veins recanalize after an episode of thrombosis, some may remain occluded. Secondary incompetence develops in distal valves because high pressures distend the vein and separate the leaflets.
Primary deep venous thrombosis can also occur without previous thrombosis. Patients with venous thrombosis often complain of a dull ache in the leg that worsens with prolonged standing and resolves with leg elevation. Examination reveals increased leg circumference, edema, and superficial varicose veins.
The presence of a thrombus in a vein may be accompanied by an inflammatory response in the vessel which may be minimal or may be characterized by granulocyte infiltration, loss of endothelium, and edema. This inflammatory process may also result in a low-grade fever.
Smoking and obesity are the most robust risk factors in the development of DVT. Diabetes, sedentary lifestyle, hypertension, hyperlipidemia, increasing age, prolonged immobility, surgery, trauma, malignancy, pregnancy, estrogenic medications (e.g., oral contraceptive pills, hormone therapy, tamoxifen (Nolvadex)), congestive heart failure, hyperhomocysteinemia, diseases that alter blood viscosity (e.g., polycythemia, sickle cell disease, multiple myeloma), and inherited thrombophilias are other potential risk factors in the development of DVT.
Venous insufficiency
The edema of venous insufficiency can be differentiated from chronic lymphedema as venous insufficiency edema is softer, and there is often erythema, dermatitis, and hyperpigmentation along the distal aspect of the leg. Skin ulceration may occur near the medial and lateral malleoli.
Obesity is commonly associated with venous insufficiency.
Peripheral artery disease
Peripheral artery disease (PAD) is the presence of systemic atherosclerosis in arteries distal to the arch of the aorta. As a result of the atherosclerotic process, patients with PAD develop narrowing of these arteries.
Patients with PAD have a history of claudication, which manifests as cramp-like muscle pain occurring with exercise and subsiding rapidly with rest. In addition, later in the course of the disease, patients may present with night pain, nonhealing ulcers, and skin color changes.
An ankle-brachial index (ABI) can be done to determine the presence of PVD. An ABI of < 0.9 is consistent with the disease. Classic risk factors for PAD are smoking, diabetes mellitus, hypertension, and hyperlipidemia. Obesity (body mass index (BMI) > 30) increases risk for PAD as well.
Recent trials have added chronic renal insufficiency, elevated C-reactive protein levels, and hyperhomocysteinemia to the list of risk factors.
The greatest modifiable risk factor for the development and progression of PAD is cigarette smoking. Cigarette smoking increases the odds for PAD by 1.4 for every ten cigarettes smoked per day.
Arterial insufficiency is four times more prevalent in patients with diabetes than in those without diabetes. Nearly half of patients who’ve had diabetes for 20 years or more have PAD, usually below the knees.
alue of Diagnostic Tests
Sensitivity is the proportion of patients with disease who test positive.
Sensitivity = True Positives/True Positives PLUS False Negatives
Specificity is the proportion of patients without disease who test negative.
Specificity = True Negatives/True negatives Plus False Positives
Positive Predictive Value is the probability the person with a positive test result actually has the disease being tested for.
PPV = True Positives/True Positives +False Positives
Negative Predictive Value is the probability the person with a negative test result does not have the disease being tested for.
NPV = True Negative/False Negative +True Negative
Sample 2X2 table. Test sensitivity is 98%. Test specificity is 95%. Prevalence of disease is 1 in 100. 10,000 people are screened with the test.
disease
no disease
test +
98
492
test –
2
9408
The positive predictive value (PPV) is 98/(98+492) = 16.6%. Even though the screening test has a sensitivity of 98%, a patient with a positive test result in this low prevalence population has only a 16.6% chance of having the disease.
Some commonly used screening tests have poorer test characteristics than this example. For example, PSA for prostate cancer screening has the following test characteristics, depending upon the cutoff for a positive test:
Cut-off 3.1 ng/mL; sensitivity 32.2% and specificity 86.7%
Cut-off 1.1 ng/mL; sensitivity 83.4% and specificity 38.9%
It is important to understand the characteristics of studies you order to better interpret what the results really mean.
Dr. Hill asks:
“What test do you think we should order?”
You tell Dr. Hill, “I guess we should have a Doppler ultrasound done because it has the best predictive value for a DVT.”
“Suppose I told you that this test was relatively expensive and often overused,” Dr. Hill proposes, “Would that change your thinking?”
You respond, “Well you mentioned that the D-dimer test is highly sensitive. Perhaps we could rule out DVT by doing that one.”
“Very good thinking. That is precisely the appropriate role of that study. But, remember that the D-dimer test is best used to rule out a DVT if the pretest probability of having a DVT is relatively low.”
“Is there some way to estimate Mr. Smith’s pretest probability of having DVT?”
“I have read that no singular clinical finding is helpful in that,” you tell her.
“That is true,” Dr. Hill concurs. “But if we use several clinical findings, we may be able to do a better job of predicting pretest probability. I am speaking here of the Wells criteria.”
TEACHING POINT
Wells Criteria for the Diagnosis of DVT
Active cancer (treatment ongoing or within previous six months or palliative)
1
Paralysis, paresis, or recent plaster immobilization of the legs
1
Recently bedridden for more than three days or major surgery within four weeks
1
Localized tenderness along the distribution of the deep venous system
1
Entire leg swollen
1
Calf swelling by more than 3 cm compared with the asymptomatic leg (measured 10 cm below the tibial tuberosity)
1
Pitting edema (greater in the symptomatic leg)
1
Collateral superficial veins (non-varicose)
1
Alternative diagnosis as likely or more likely than that of deep vein thrombosis
-2
Low probability 0 or less, moderate probability 1–2, high probability 3 or more.
Which of the following would you order at this point?
Select all that apply.
The best options are indicated below. Your selections are indicated by the shaded boxes.
A. Arterial blood gas
B. Chest x-ray
C. Complete blood count
D. C-reactive protein
E. Electrolytes, glucose, creatinine, and blood urea nitrogen (BUN)
F. Hemoglobin A1C
G. Sedimentation rate
H. Thyroid studies
SUBMIT
Answer Comment
The correct answers are C, E, F.
A CBC (C ) with leukocytosis might make you consider an infectious process. Given you are in clinic and he has not been seen in almost 6 months electrolytes, glucose, BUN & creatinine (E) as well as a Hemoglobin A1c (F) would be important to evaluate diabetic control and renal function.
Arterial blood gas (A) or chest x-ray (B) in a patient without symptoms of respiratory difficulty is unlikely to be useful.
Sedimentation rate (G) and c-reactive protein (D) might be elevated, but would be in both cellulitis and DVT, so it is not particularly useful in determining a diagnosis at this point.
Thyroid studies (H) are unlikely to provide any useful information about the absence of signs and symptoms of thyroid disease.
Several days have gone by and you and Dr. Hill are now rounding on your patients in the hospital. When you get to Mr. Smith, you tell Dr. Hill:
“This is Mr. Smith’s third day in the hospital. He says he is feeling better, the pain and swelling in his leg is improving. His temperature is 36.2 °C (97.2 °F), his pulse is 80 beats per minute, his respiratory rate is 16 breaths per minute, his blood pressure is 128/78 mmHg. On exam, his foot ulcer has some fresh granulation tissue on the wound edges. Labs include his fasting glucose this morning was 128 mg/dL (7.0 mmol/L). His CBC was normal and his platelets are stable from admission.”
Dr. Hill responds, “Good. I just got word from his pharmacy that the enoxaparin has now been approved by his insurance, so if he can inject himself for two more days, he can go home. We will need to arrange a close follow-up with visiting nurses and at our office, so he can continue his treatment for his diabetic foot ulcer.”
You comment, “This all seems so much easier than it would have been if he were taking warfarin. How long would it take to get his INR to the therapeutic range if he were using warfarin?”
Dr. Hill tells you, “It varies a lot from person to person, but it commonly takes at least five days for a patient’s INR to get above 2.0. When starting it, you have to balance speed with the risk of overshooting his INR goal and ending up increasing his risk of bleeding by making him supratherapeutic. It is good to consider warfarin dosing since it is still commonly used. It is a very effective medication, but it can be dangerous as well.”