The Hare and the Tortoise 2)Describe mitigating strategies - PowerPoint PPT Presentation

6/19/2019 Session goals 1)Recognize pitfalls in the diagnostic reasoning process The Hare and the Tortoise 2)Describe mitigating strategies 3)Understand why I’ve chosen this silly analogy Improving Our Approach to Clinical Reasoning Bradley Monash, MD Associate Professor, Medicine & Pediatrics Associate Chief, Division of Hospital Medicine UCSF Division of Hospital Medicine Session Agenda 1) Diagnostic error 2) Four illustrative cases 3) The diagnostic process 4) Mitigating strategies 1

6/19/2019 Origins of diagnostic error in 100 patients Dx Errors Are Common 19% Systems Error 28% • Autopsy series 1966-2002 Cognitive • “ Major errors ” (missed diagnosis that would have Error 46% Systems changed management): 23.5% • “ Class I errors ”: (missed diagnosis that may have and Cognitive contributed to death): 9.0% Errors 7% due to “no fault” error ~40k-80k inpatients/yr may die with a missed diagnosis (e.g, unusual presentation; rare disease) Arch Int Med 2005; 165(13): 1493-9. 4 cases Watson, MD? 2

6/19/2019 Case 1: Case 1: Continued Burma Superstar T 100.8 P 91 BP 104/74 RR 20 SpO2 98% RA • 65-year-old man returned from Myanmar 7d • Ill, non-toxic appearing ago, presenting with 2d fevers and a rash. • Pale conjunctivae, MM tacky • Regular, soft systolic murmur at apex • USOH until 2d ago, developed fevers to 102, chills, macular rash on extremities. • Lungs clear • Abd soft, nd/nt • ROS notable for 5 lb weight loss, malaise • Ext wwp • Macular, pinpoint erythematous rash on legs Case 1: Continued Case 1: Continued T 100.8 P 91 BP 104/74 RR 20 SpO2 98% RA • Ill, non-toxic appearing • Pale conjunctivae, MM tacky • Regular, soft systolic murmur at apex • Lungs clear • LFTs wnl • Abd soft, nd/nt 72% PMNs • Coags wnl 19 % lymphs • Ext wwp • UA neg 9% monos • Macular, erythematous rash on legs • CXR clear 3

6/19/2019 What’s your next move? 83% A. Provide supportive care without diagnostic evaluation B. Send dengue serologies and discharge with follow-up 17% C. PET scan 0% 0% 0% D. Bone marrow biopsy E. Travel to Myanmar to uncover the elusive PET scan Bone marrow biopsy Send dengue serologies and ... Travel to Myanmar to uncov.. Provide supportive care wit... source of his fevers https://www.cdc.gov/mmwr/preview/mmwrhtml/ss6203a1.htm Case 1: Continued 2 weeks later… • Dengue serologies sent • Supportive care • More fevers - IVF, friendly banter • More rash • More malaise • Dengue negative • Readmitted • Discharged with plan for outpatient follow-up 4

6/19/2019 What’s your next move? A. Provide supportive care without diagnostic evaluation 65-year-old man with fevers, B. Send dengue serologies and discharge with follow-up C. PET scan weight loss, petechiae and D. Bone marrow biopsy pancytopenia E. Travel to Myanmar to uncover the elusive source of his fevers 5

6/19/2019 What’s your next move? A. Provide supportive care without diagnostic evaluation B. Send dengue serologies and discharge with follow-up C. PET scan D. Bone marrow biopsy E. Travel to Myanmar to uncover the elusive source of his fevers 65-year-old man returned from 65-year-old man returned from Myanmar, Myanmar, p/w 2d fevers and a rash. p/w 2d fevers and a rash. 6

6/19/2019 Framing 65-year-old man returned from Mexico, The error of initiating diagnostic reasoning by overvaluing an item of clinical information that p/w 2d fevers and a rash. is presented early in the process. 7

6/19/2019 Would you intervene? Lancet 1992;339:1520–1522 Radiation vs. Surgery? Framework Survival vs. Mortality 90/100 survive vs. 10/100 die Radiation vs. Surgery “Survive”: 16-17% “Die”: 40-50% N Engl J Med 1982;306:1259-1262. 8

6/19/2019 Case 2: Fog Harbor Case 2: Continued • 63-year-old woman with h/o pancreatic divisum, • Pain recurred suddenly at ~1am. hysterectomy, presenting with 3 weeks of intermittent • +Nausea, emesis. No stool x 2 days. abdominal pain, nausea/vomiting. • Abdomen soft, diffusely tender, +rebound and • The pain is sharp, constant, periumbilical and RLQ, worse with “voluntary” guarding eating, associated with bilious emesis. • CT from recent admission reportedly negative • Typical “flares” last for a week prior to resolving • Admit to surgery for r/o “surgical abdomen” • Recent hospitalization without dx Case 2: Continued • Exam stabilized, no surgical process clearly identified. • “Transfer to Medicine” • Pt developed worsening pain • Pelvic ultrasound obtained 9

6/19/2019 “Pelvic fluid collection, rule out TOA” Case 2: Continued • Surgery re-consulted – deferred to Gyn for TOA management • Gynecology recommended non-operative management • Broad-spectrum IV antibiotics started for TOA • Patient feeling well: “So what’s the plan, doc?” • No malignancy • Progression of tubo-ovarian abscesses. • Thickening and hyperemia of the appendix, likely secondary to the tubo-ovarian abscesses. 10

6/19/2019 What’s your next move? Case 2: Continued 33% 33% A. Tell surgery to take out the appendix! • Fluid sampled by IR – no growth (on abx) 25% B. Call IR to drain the fluid • Discharged on abx with outpatient follow-up for malignancy C. Setup a PICC for home antibiotics • 2 more admissions for the same symptomatology D. Order a PET to find an occult malignancy 8% • Query: pseudomyxoma peritonei E. TOA’s make you weary, so to make up your 0% • Scheduled for elective ex-lap and appendectomy mind you’re asking SIRI d i . . u . . . . l i . . . . f b l . . t e i u e t o h h n c t c s t a o , t n y u e n r i m a o a a r e e d o d w k h n o a r f i u t t o R o o o f y t I C t l T e y l C r a I E k e C P P a m g a a r u p r s s e u A ’ l t d l e r O e O T S T Case 2: Continued Operative Note Laparoscopic appendectomy converted to open partial cystectomy due to erosion of appendiceal pathology into her bladder. Pathology Appendix with fibrous obliteration and dissecting acellular organizing mucin, consistent with past rupture 11

6/19/2019 What’s your next move? What’s your next move? A. Tell surgery to take out the appendix! A. Tell surgery to take out the appendix! B. Call IR to drain the fluid B. Call IR to drain the fluid C. Setup a PICC for home antibiotics C. Setup a PICC for home antibiotics D. Order a PET to find an occult malignancy D. Order a PET to find an occult malignancy E. TOA’s make you weary, so to make up your mind you’re E. TOA’s make you weary, so to make up your mind you’re asking SIRI asking SIRI Blind Obedience Showing undue deference to technology or authority. Tubo-ovarian abscess? 12

6/19/2019 “ Nobody ’ s perfect. ” Anchoring The formulation of an initial probability of a diagnosis based on information at hand, and not adjusting this probability as new clinical data are obtained. 13

6/19/2019 “Estimate percentage of countries in Africa that are members of the United Nations (UN).” 25% Science 1974. 185;4157:1124-31 14

6/19/2019 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1 = 2250 1 x 2 x 3 x 4 x 5 x 6 x 7 x 8 = 512 45% Science 1974. 185;4157:1124-31 “Admit for ____” “Admitted for ____” 15

6/19/2019 “Assess for ____” “Consult for ____” Case 3: Deja Vu • A 67-year-old woman with h/o DM and HTN, presented with 4 months of abdominal pain and recurrent nausea • Periumbilical pain, worse with eating. +Diarrhea, decreased appetite, weight loss • Multiple negative outpatient investigations • CBC, chemistries, LFTs, stool cx + O&P, anti-TTG • CT: L adrenal cyst, atheroma within the abdominal aorta, uncomplicated cholelithiasis https://pxhere.com 16

6/19/2019 Case 3: Continued • Admitted with ongoing pain and PO intolerance • +Nausea, diarrhea • Abdomen soft, diffusely tender, +rebound and “voluntary” guarding • Repeat labs unrevealing • Prior CTs reviewed without obvious source… Ther Adv Gastroenterol 2015.8;(3):160–2 thepix.info What’s your next move? Case 3: Continued A. Tell surgery to take out the appendix! 77% • Continued abx, multiple consultants following B. Order a PET to find an occult malignancy • Several days later, severe abdominal pain, increased C. Order CT angiography of the mesenteric vessels tenderness with worsening peritoneal signs, WBC 16k • CT angiography: severe ostial stenoses of the celiac and D. Order MR enterography and fecal calprotectin 18% superior mesenteric arteries E. I don’t care – I’m done with these mind games 0% 5% 0% . . . . . . . . . . d . . . . l . e u h n h c t a t h i t c o f y w o h u t e n y p o a h a n p o e d r k a g d n r o a i g r m t f o e o ’ o g i t I t t n – T n e y a e r E R r e P T a M g a C c r u r r r t s e e e n ’ d d d l r r o e l r O O d O T I 17