Secrets of Experts in ClinicalDecision Making: Schemes of Care Dr. Imad Salah Ahmed Hassan MD FACP FRCPI MSc MBBS Consultant Physician & Pulmonologist Chairman, Knowledge Translation Committee Department of Medicine King Abdulaziz Medical City Riyadh, Saudi Arabia firstname.lastname@example.org
Summarize the CaseStep 2 using Technical Language
Step 2• Comprehensive but Concise, Text-book-Like:• Must contain patient’s name, gender, age,• occupation, nationality racial/geographic origin, relevant Past History/Social History/Family History, Drug/Allergic History, Symptoms + duration –in technical terms, Relevant physical signs in technical conclusive terms.
Step 2: Case Presentation Example• 67 yr old male• Bird/pigeon breeder, smoker• 3 days history of fever, cough with yellow sputum, left stabbing chest pain that is worse with breathing and coughing and breathlessness• Clinically, breathless, cyanosed, disoriented to time, person and place, Temperature 39.1C, BP 86/50, RR 32/min, bilateral coarse crepitations, bronchial breathing left lower zone.• Chest x-ray: left basal consolidation
Step 2: Case Technical Summary• 67 year old, smoker and bird-breeder presenting with a 3 days history of productive cough, dyspnea and left pleuritic chest pains.• Clinically confused, cyanosed, febrile, tachypnoiec and hypotensive with signs of left lower zone consolidation.
Step 3: Use Bed-side Diagnosis Schemes• Pattern-recognition• Smart Heuristics• Rule-Out worst Scenario ROWS• Red Flags (symptoms or signs of more serious pathology) etc• Hypothetico-deductive Strategies (from H&P)
Step 3: Use Bed-side Diagnosis Schemes• High-Fidelity/Reliability Pattern Recognition (spot diagnosis): Shingles, Acromegalic Facies• Low-Fidelity/Reliability Pattern Recognition (error-prone): Central chest pain radiating to the left arm plus sweating, nausea and vomiting =Acute Coronary Syndrome (other possibilities still exist!)• Smart Heuristic “Rules of Thumb”: early morning headache and vomiting=Increased intracranial pressure• ROWS: Meningitis, SAH, CVA, Temporal Arteritis etc in a patient with headache• Red Flags: rest pain, weight loss, neurological deficits etc in a patient with low back pain
Step 3: Use Bed-side Diagnosis Schemes• Hypothetico-deductive Strategies (from H&P)• Detailed history• Clues from all components of the history• Comprehensive physical examination• May need to revert to investigations if no diagnosis is clear.
Step 4: Use Differential Diagnosis Schemes• Differential Diagnosis Cognitive Aids: Anatomical Physiological Pathological An important cause of missing a diagnosis is not thinking of it!!! i.e. not putting a differential diagnosis.
Step 4: Use Differential Diagnosis Schemes Anatomical Differential Physiological Differential Etio-pathological Differential Diagnosis Diagnosis DiagnosisPain Syndromes: e.g. central Shock: this may be Congenital or Hereditarychest pain may be categorized hypovolemic, distributive,as arising from the heart, obstructive or cardiogenicaorta, esophagus, chest walletcSwellings: e.g. a neck swelling Thrombosis: This may be Acquired:differential diagnosis will related to a vessel wall 1. Traumaticinclude the thyroid, lymph pathology, blood constituents 2. Infective: viral, bacterialnodes, vascular, skin etc or flow rate. etc 3. Inflammatory/auto- immune 4. Vascular/degenerative 5. Neoplastic/para- neoplastic 6. Metabolic/endocrine 7. Drug-induced/ poisoning 8. Deficiency diseases 9. Psychogenic 10. Idiopathic/cryptogenic
Step 5: Pre-test Probability Assessment for Rational Test Ordering• Frugal (simple and applicable) Heuristics Probability Assessment• Order tests: based on Test Sensitivity, Specificity and Likelihood Ratios• Baye’s may not be a practical and quick pre-test probability assessment approach!
Step 5: Pre-test Probability Assessment for Rational Test Ordering• Frugal Pre-test Probability Assessment:• 1. Strong Risk factor for the condition: Yes/No• 2. No alternative plausible bed-side Diagnosis: Yes/No• Interpretation: High (2 YES) or Intermediate (1 YES 1 NO) or Low (2 NO)
Step 5: Pre-test Probability Assessment for Rational Test Ordering• SpIn: highly specific tests are useful for ruling-in the diagnosis when positive ( use for high and intermediate probabilities) e.g. spiral CT for suspected pulmonary embolism.• SnOut: highly sensitive tests are useful for ruling-out the diagnosis when negative ( use for low probabilities) e.g. d- dimer for suspected pulmonary embolism.
Sensitivity • How often is the test result correct for persons in whom the disease is known to be present?SENSITIVITY • Sensitivity - the proportion of people with disease who have a positive test. • in a group of 100 patients with bacterial pneumonia, 80 had a raised C-reactive Example: protein CRP: the sensitivity of CRP for diagnosing bacterial pneumonia is thus 80%.
Specificity • How often is the test result correct for persons inSPECIFICITY whom the disease is known to be absent? • Specificity - the proportion of people without the disease who have a negative test. • in a group of 100 patients without pneumonia, 10 had a raised C-reactive Example: protein CRP: the specificity of CRP for correctly excluding pneumonia is thus 90%.
Likelihood Ratio • the likelihood that a given test result would be expected in a patient with the target disorder compared to the likelihood that the sameLikelihood result would be expected in a patient without that disorder. • In general, a positive likelihood ratio of 4 or ratio: more is useful in ruling-in the target disorder. A negative likelihood ratio of less than 0.3 is useful in ruling-out the target disorder.
Likelihood Ratio • Example: A raised Jugular venous pressure JVP in a patient with a historyLikelihood suggestive of congestive heart failure CHF has a positive LR of 5.8 and a ratio: negative ratio of 0.66. Thus the presence of a raised JVP rules-in the diagnosis of CHF. Its absence is not as useful in ruling it out.
Confirm &Step 6 Comprehensively give a Diagnostic Label
The BESDiagnosis SchemeBetter diagnostic labeling thereby assisting in implementing individualized, evidence- based interventions.• 1. The Bed-side Clinical Diagnosis• 2. The Etiological or Precipitating Cause• 3. The Severity Score or Grade.
Guideline-friendly Bed-side “the Diagnosis, Etiology, Severity (BESD) diagnosis that would explain all Bedside Clinical the Diagnosis symptoms & signs” Etiological/ “what is the Precipitant Cause”•CURB-65: CAP•Killip Classes: ACS “how bad”•Glasgow CS•Croup Score Severity•APGAR Score•Blatchford score: UGI bleed•Ranson Score: Pancreatitis•Emerg. Severity Index
Usefulness of The Scheme• Failure to consider the precipitant or cause in addition to the clinical diagnosis will inevitably result in deficient care input and a poorer outcome.• Appropriate evidence-based interventions to optimize outcome according to SEVERITY will be different specifically with regards the sites of care and recommended Immediate Interventions.
Usefulness of The Scheme• e.g.• Usual Label: “Admitted with an asthma exacerbation…………• Guideline-Friendly Evidenced-Based Label:1. The Bed-side Clinical Diagnosis: Asthma Exacerbation2. The Etiological or Precipitating Cause: Poor Inhaler Technique3. The Severity Score or Grade: Life-threatening Asthma
Usefulness of The Scheme• e.g. Continued….• Implications:• Site of Care: ICU• Therapy for life-threatening attacks: Oxygen, systemic steroids, combination nebs etc• Prevention of re-admission: training on inhaler technique
Step 7: Therapeutic Interventions: The 5S Scheme• Contextual• Patient-centered – Therapeutic Cognitive Aid: Site of Care, Symptomatic, Supportive, Specific and Specialty Referral (5S).
Immediate Therapeutic Interventions: The 5S Site of Care e.g. CCU Symptomatic e.g. Analgesics e.g. Supportive IV fluids e.g. Specific thrombolytic Specialty e.g. Referral cardiology
The 5 S Scheme• Site of Care: Guidelines, unambiguously dictate sites of care for specific disease severity scores.• ICU for CURB-65 of 3 or more• CCU for Acute Coronary Syndrome
The 5 S Scheme• Symptomatic treatment: is important as it directly alleviates patient discomfort.Analgesia for painAnti-emetics for nausea and vomitingAnti-pyretics for fever
The 5 S Scheme• Supportive care: to improve physiological derangements before damage becomes irreversible and until the precipitant is brought under control by its specific intervention may be life-saving.IV Fluids for dehydrationBicarbonate for acidosisOxygen for hypoxia
The 5 S Model The 5 S Scheme• Specific Care: directed at the primary cause.Antibiotics for infectionThrombolytics for acute myocardial infarctionAppendicectomy for acute appendicitis
The 5 S Model The 5 S Scheme• Specialty Referral: guidelines recommend early specialty or sub-specialty referral for specific acute illnesses.GIT team for a patient with hematemesisCardiology for a patient with ACSPhysiotherapy for a patient with stroke
The complete input: An Example1. Bedside-Clinical Diagnosis Acute BA Exacerbation2. Precipitant Poor Inhaler Technique3. Severity Life-threatening4. Site of Care ICU5. Symptomatic Bronchodilators6. Supportive Oxygen, IV Fluids7. Specific Bronchodilators, Steroids8. Specialty Referral ICU, Pulmonary, Asthma Educator
Step 8: Prepare for Discharge (ACT)• Assess Response to Treatment (Subjective & Objective)• Criteria for Discharge• Timing of Follow-up
The ACT Scheme• Assess Response to Treatment: Subjective & Objective• Criteria for Discharge: Clinical, Laboratory, Radiologic, Social etc• Timing of Follow-up : Clinic Appointment for disease and drug monitoring