Cheat Sheet - Clin Path Lecture 1

University:
University of California, San Diego
Course:
BIMM 100 | Molecular Biology
Academic year:

2025
Views:

325

Pages:

43
Author:

Aestherielle Seraphine

Intro Here is your HIGH-YIELD, CRAMMING-STYLE CHEAT SHEET for Intro to Clinical Pathology based on your lecture + past UERM exams + quiz patterns. I highlighted the most commonly tested and professor-favorite topics so you can focus while cramming. This is written simple, step-by-step, with analogies, like your Surgery 2 long exams style. 🔥 If you want, I can later add: • MCQ exam set • Case-based simulations • Mnemonics • Flowcharts • Predicted long exam questions Just tell me. 📌 INTRO TO CLINICAL PATHOLOGY HIGH-YIELD SURGERY 2 LONG EXAM CHEAT SHEET 🧠 BIG PICTURE (Most tested concept) 👉 Clinical Pathology = Laboratory Medicine 📌 Definition It is the branch of pathology that diagnoses disease using laboratory analysis of body fluids like blood, urine, CSF, etc. 🧒 Analogy Think of the lab as the detective and the doctor as the judge. The doctor decides based on evidence. The lab provides the evidence. ⭐️ WHY THIS IS SUPER HIGH-YIELD ✔ Appears in quizzes and long exams ✔ Foundation for ALL clinical decisions ✔ Used in Surgery and Internal Medicine 👉 70–80% of clinical decisions depend on lab tests 💡 Prof loves this number. MEMORIZE. 📌 I. USES OF LABORATORY TESTS (TOP FAVORITE QUESTION) Always asked in exams. ✔ 5 MAIN USES 1️⃣ Diagnostic Detect disease NOW Example: Troponin for MI 2️⃣ Screening Detect disease before symptoms Example: Newborn TSH 3️⃣ Prognostic Predict future outcome Example: Tumor markers 4️⃣ Monitoring Follow disease or treatment Example: Glucose monitoring 5️⃣ Epidemiologic Population studies Example: Malaria surveillance 📌 Mnemonic: 👉 DSPME Diagnosis Screening Prognosis Monitoring Epidemiology ✔ This appears repeatedly in past exams. 🧒 Analogy Lab tests are like: • Camera → diagnose • CCTV → monitor • Weather forecast → prognosis • Mass testing → epidemiology 📌 II. BASIC PRINCIPLES OF LAB TESTING ⚠️ VERY HIGH-YIELD (prof favorite) ⭐️ A. NO TEST IS PERFECT Every test has: • False positives • False negatives 👉 No test is 100% sensitive or specific. 🧒 Analogy Even the best metal detector sometimes misses coins. ⭐️ B. PRIOR PROBABILITY Tests must depend on: • History • Physical exam • Disease prevalence 👉 NEVER request labs without clinical suspicion. 💡 Surgery connection Example: Do not request CT scan in all abdominal pain. ⭐️ C. MULTIPLE ABNORMAL TESTS = MORE SIGNIFICANT If many tests abnormal → more likely real disease. ✔ Appears in exam. Example: High creatinine + high BUN = kidney disease. 📌 This is a classic MCQ trap. ⭐️ D. CRITICAL VALUES Dangerous lab values → must be reported immediately. Example: • Potassium 7 • Platelets very low ⭐️ E. DEGREE OF ABNORMALITY The more abnormal → the more real. Example: • Creatinine 1.5 → maybe variation • Creatinine 6 → real disease ⭐️ F. TOO MANY TESTS = BAD Reasons: • Waste money • Confusing • Increase errors ⭐️ G. POSITIVE ≠ ALWAYS DISEASE Negative ≠ always normal. Because: • Sensitivity • Specificity • Prevalence 🧒 Analogy A pregnancy test may be false early. 📌 III. REFERENCE VALUES (EXAM FAVORITE) ⭐️ KEY CONCEPT 👉 Normal range = 95% of healthy population. 5% will be abnormal even if healthy. ✔ This question always appears. Example: FBS 103 mg/dL in asymptomatic → may still be normal. 🧒 Analogy If 100 students take exam: 5 will fail even if they studied. 📌 IV. TEST PERFORMANCE ⭐️ ACCURACY vs PRECISION (VERY HIGH-YIELD) ✔ Accuracy Closeness to TRUE value. ✔ Precision Reproducibility. 📌 Precision more important in lab. 🧒 Analogy Dartboard: • Accuracy → hitting center • Precision → arrows close together 📌 V. SENSITIVITY & SPECIFICITY ⚠️ TOP BOARD-TYPE QUESTION ⭐️ Sensitivity Detects disease when present. Few false negatives. 👉 Mnemonic: SnNout High sensitivity → negative rules OUT. ⭐️ Specificity 👉 Detects absence of disease. Few false positives. Most errors occur in: PRE-ANALYTICAL PHASE 👉 ✔ Appears repeatedly in exams. Mnemonic: SpPin High specificity → positive rules IN. ✔ Frequently tested. 🧒 Analogy Security: • Sensitive alarm → detects everything • Specific alarm → only real threats 📌 VI. PREDICTIVE VALUE Depends on: • Prevalence • Sensitivity • Specificity Example: Rare disease → low PPV. 📌 VII. LABORATORY ERRORS ⚠️ VERY HIGH-YIELD ⭐️ THREE PHASES 1️⃣ Pre-analytical (MOST ERRORS) Before testing: • Wrong patient • Poor collection • Transport • Tube errors 2️⃣ Analytical Actual testing: • Machine • Reagents 3️⃣ Post-analytical After testing: • Reporting • Interpretation 🧒 Analogy Cooking: • Pre → buying ingredients • Analytical → cooking • Post → serving Most mistakes happen when buying. 📌 VIII. SPECIMEN COLLECTION ⚠️ EXTREMELY HIGH-YIELD IN SURGERY ⭐️ Key Principles ✔ ✔ ✔ ✔ Correct patient Correct tube Proper labeling Proper timing ⭐️ Specimen rejection causes Very commonly tested: • Insufficient volume • Wrong tube • Hemolyzed sample • Missing patient info ✔ Must recollect. 📌 IX. PHLEBOTOMY ⚠️ VERY HIGH-YIELD (appears every year) ⭐️ Venipuncture supplies Needle Tourniquet Alcohol Vacutainer ⭐️ Complications • Hematoma • Syncope • Infection 👉 If faint: Lay patient down. ⭐️ CAPILLARY BLOOD Used when: • Difficult veins • Neonates ⭐️ MOST IMPORTANT RULE Tourniquet < 1 minute Long time → hemoconcentration. ✔ Appeared in quizzes. ✔ Gray Glucose, alcohol ✔ Always tested. 📌 X. BLOOD COLLECTION TUBES ⚠️ SUPER HIGH-YIELD ⭐️ COLOR CODING ⭐️ ORDER OF DRAW 🔥 VERY COMMON EXAM 👉 Mnemonic: Stop Light Red Stay Put Green Light Go Order: 1. 2. 3. 4. 5. 6. 7. ✔ Yellow Blood culture ✔ Light blue Coagulation Blood culture Blue Red SST Green Lavender Gray ✔ Red ✔ Prevent contamination. Chemistry 📌 XI. SPECIAL HANDLING ✔ Green Heparin ✔ Purple CBC ⚠️ High yield ✔ Serum ammonia Ice. ✔ Bilirubin Protect from light. ✔ Appears in exams. 🔥 ULTRA-HIGH-YIELD SUMMARY (CRAMMING) If you only have 5 minutes: 📌 XII. BIOSAFETY High yield in long exam. ⭐️ PPE ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ 70–80% decisions based on lab Uses of lab tests (DSPME) No test is perfect Sensitivity vs specificity Reference range = 95% Multiple abnormal tests significant Most errors = pre-analytical Order of draw Tube colors Special handling Depends on risk. ⭐️ Biosafety cabinet Protects staff from pathogens. ✔ Example question. Would you like me to also make: 1. 2. 3. 4. 5. 🔥 40–50 exam-style MCQs based on your 2023–2026 exams Case-based long exam simulations Visual flowcharts Mnemonics and memory tricks Predicted questions your prof will ask Tell me what will help you most so I can tailor it to your Surgery 2 long exam. 📌 XIII. RISK GROUPS Example: Anthrax → Group III. RBC Here is your DRAFT high-yield cheat sheet based on your uploaded lecture + past UERM exams and PasaDOUGH. I focused on frequently tested topics, lab interpretation, and exam traps. Please review first. Tell me what to adjust before I finalize and expand (for example add MCQs, flowcharts, or case simulations). 🔥 RBC DISORDERS CHEAT SHEET (HIGH-YIELD) For UERM Clinical Pathology Long Exams (Simple, step-by-step, analogy style) 🧠 BIG PICTURE (Most important mindset for exams) 👉 Think of anemia like a factory problem: Question Meaning Are RBCs not produced? Bone marrow problem Are RBCs destroyed? Hemolysis Are RBCs lost? Bleeding 👉 So your FIRST step in any anemia question is: Look at the RETICULOCYTE COUNT 🔥 STEP 1: INITIAL LAB TESTS (MUST KNOW) According to your lecture outline, these are the key parameters used to evaluate RBC disorders. ✔ CBC + RBC indices ✔ Reticulocyte count ✔ Peripheral smear ✔ Iron studies ✔ Hemoglobin electrophoresis 🧪 1. Hemoglobin (Hb) ✔ What it tells you ● Oxygen-carrying capacity ● Severity of anemia ● Polycythemia detection Used to: ● Diagnose anemia ● Monitor treatment ● Assess severity 🧠 Analogy 👉 Hb = number of “oxygen trucks” in the body. 🧪 2. Hematocrit (Hct) ✔ Definition Proportion of RBCs in whole blood. 👉 Formula: Hct = height of RBC / height of whole blood ✔ Increased in: ● ● ● ● Dehydration High altitude Polycythemia EPO-producing tumors ⚠️ EXAM TRAP ❗ False elevation: ● Sickle cell anemia due to trapped plasma. 🧪 3. Reticulocyte Count (MOST IMPORTANT!) ✔ Why? Tells if bone marrow is working. ✔ Interpretation Retic Meaning HIGH RBC destruction or blood loss LOW Bone marrow failure or deficiency Example: ● Hemolysis → ↑ reticulocytes ● Aplastic anemia → ↓ reticulocytes 🧠 Analogy 👉 Reticulocytes = baby RBCs If many babies → marrow is active. ✔ Corrected reticulocyte count Formula: Retic × (patient Hct / 45) 🔥 STEP 2: RBC INDICES (HIGH-YIELD) These tell size and color of RBCs. 🧪 1. MCV (size) Type ANEMIA (ULTRA-HIGH YIELD) Value ✔ STEP 1: Check MCV Microcytic <80 Normocytic 80–98 Macrocytic >98 🧪 2. MCHC (color) ● Low → hypochromic ● High → spherocytosis 🧠 Analogy 🟥 MICROCYTIC ANEMIA Causes: 1. 2. 3. 4. Iron deficiency Thalassemia Anemia of chronic disease Sideroblastic 🔥 Iron Deficiency Anemia (VERY COMMON EXAM) Think of RBC as donuts: Type 🔥 STEP 3: APPROACH TO Donut Microcytic Small donut Macrocytic Big donut Hypochromic Pale donut Labs: ● ● ● ● ↓ Serum iron ↓ Ferritin ↑ TIBC ↓ transferrin saturation RBC: ● Hypochromic ● Microcytic ● ↑ RDW ⚠️ EXAM TRAP 👉 TIBC is HIGH in iron deficiency. 🔥 Thalassemia (FAVORITE EXAM) Patho: Defective globin production. Labs: ● ↓ MCV ● Normal RDW ● Normal to ↑ RBC count PBS: ● Target cells. Diagnosis: ✔ Hemoglobin electrophoresis ✔ ↑ HbA2 and HbF in beta-thalassemia ⚠️ EXAM TRAP 👉 Microcytic anemia + normal RBC count = THALASSEMIA. Causes: ● ● ● ● Acute blood loss Hemolysis Chronic disease Bone marrow failure 🔥 Anemia of Chronic Disease Labs: ● ↓ Serum iron ● ↑ Ferritin ● ↓ TIBC 🔥 Aplastic anemia Findings: ● Pancytopenia ● ↓ reticulocyte count 🟦 MACROCYTIC ANEMIA Causes: 🟨 NORMOCYTIC ANEMIA 1. B12 deficiency 2. Folate deficiency 🔥 Megaloblastic anemia ✔ Intravascular vs extravascular Labs: ● ● ● ● Feature ↑ MCV ↑ LDH ↑ homocysteine ↑ methylmalonic acid (B12 only) PBS: ● Macrocytes ● Hypersegmented neutrophils. ⚠️ EXAM TRAP Intravascular Hemoglobinuria Yes Tea-colored urine Yes Splenomegaly No Jaundice Yes 🧪 1. Coombs test 🔥 STEP 4: HEMOLYTIC ANEMIA Detects antibodies on RBC. ✔ Signs of hemolysis: ● ● ● ● ↑ bilirubin ↑ LDH ↓ haptoglobin ↑ reticulocytes Yes 🔥 SPECIAL TESTS (SUPER HIGH YIELD) 👉 Only B12 increases methylmalonic acid. (VERY HIGH YIELD) Extravascular Used for: ● Autoimmune hemolytic anemia 🧪 2. Osmotic fragility test Measures RBC rupture in saline. ↑ Osmotic fragility: 👉 Hereditary spherocytosis Why? ● Spherical cells burst easily. ✔ Spherocytes Seen in: ↓ Osmotic fragility: 👉 Sickle cell anemia 👉 Thalassemia 🧪 3. Hemoglobin electrophoresis Used for: ● Sickle cell ● Thalassemia 🔥 STEP 5: RBC MORPHOLOGY (EXAM FAVORITE) ✔ Target cells Seen in: ● Thalassemia ● HbC ● Post splenectomy ● Hereditary spherocytosis ● ABO hemolytic disease ✔ Schistocytes Seen in: ● TTP ● DIC ● HUS ✔ Bite cells + Heinz bodies Seen in: ● G6PD deficiency ✔ Hypersegmented neutrophils Seen in: ● Megaloblastic anemia. 🔥 STEP 6: ESR (COMMON IN ✔ Increased osmotic fragility → spherocytosis ✔ Elevated HbF and HbA2 → beta-thalassemia EXAMS) Measures inflammation. ↑ ESR: ● Infection ● Rheumatic disease ● Multiple myeloma 🧠 FAST MEMORY TRICK 🔥 RETICULOCYTE RULE Retic Diagnosis High Destruction or bleeding Low Production problem ↓ ESR: ● Sickle cell anemia Because sickled cells do not stack. 🔥 ULTRA-HIGH YIELD EXAM PEARLS (UERM) ✔ ✔ ✔ ✔ ✔ ✔ Microcytic + normal RBC count → Thalassemia Microcytic + high RDW → Iron deficiency High retic → hemolysis Low retic → bone marrow failure Tea-colored urine → intravascular hemolysis Target cells → thalassemia 📌 HOW TO ANSWER LONG EXAM QUESTIONS (STEP BY STEP) 1. 2. 3. 4. Check MCV. Check reticulocyte count. Look at peripheral smear. Confirm with special tests. ✔ MOST COMMON TESTED DISEASES (Based on your exams) 🔥 Iron deficiency 🔥 Thalassemia 🔥 Hemolytic anemia 🔥 Megaloblastic anemia 🔥 Spherocytosis 🔥 Sickle cell ✔ MOST COMMON LAB QUESTIONS ● ● ● ● ● Iron studies interpretation Reticulocyte count Osmotic fragility Hemoglobin electrophoresis RBC morphology. MCV ↓ ↓ RDW ↑ Normal RBC ↓ Normal or ↑ Iron ↓ Normal Ferritin ↓ Normal TIBC ↑ Normal Target cells No Yes 🔥 FINAL SUMMARY (If you remember nothing else) ✔ MOST COMMON TRAPS ❗ TIBC direction ❗ Methylmalonic acid ❗ RDW differences ❗ Reticulocyte interpretation. 👉 Reticulocyte + MCV + smear = diagnosis. ✅ Draft ready. Would you like me to also add: ✔ MUST MEMORIZE TABLE (HIGH YIELD) Feature IDA Thalassemi a 1. 2. 3. 4. 5. 6. 🔥 40–50 UERM-style MCQs Case-based long exam simulations Flowchart algorithm (very high yield for exams) Visual memory tables Comparison charts for all anemia types Predicted exam questions based on past trends Tell me what you want before I finalize. WBC Here is your DRAFT high-yield cheat sheet for your Clinical Pathology (WBC disorders) long exam. I based this on your lecture + past exams + quiz patterns (especially UERM style). Review first and tell me if you want edits, MCQs, flowcharts, or predicted questions before I finalize. 🧠 WBC DISORDERS CHEAT SHEET (High-yield, Surgery 2 long exam, UERM style) 🩸 I. WHAT ARE WBCs? (Start here in every viva) 👉 White blood cells = immune system soldiers. They protect the body from infection, inflammation, and foreign materials. 📌 Normal adult WBC count 👉 4,500–10,000 /µL 📌 Differential count (adult) ● ● ● ● ● Neutrophils: 60–70% Lymphocytes: 20–25% Monocytes: 3–8% Eosinophils: 2–4% Basophils: 0.5–1% 🧠 Analogy: Think of WBCs as an army: ● ● ● ● ● Neutrophils = infantry Lymphocytes = special forces Monocytes = cleanup crew Eosinophils = parasite fighters Basophils = allergy signalers 🔥 HIGH-YIELD MUST KNOW (Exam Favorite) ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ Neutrophils = most abundant First responder in infection ANC calculation Leukocytosis vs leukopenia Differential count interpretation Peripheral smear Left shift Absolute vs relative count Infection patterns 🧪 II. LABORATORY APPROACH (STEP-BY-STEP) This is VERY high yield in viva and MCQs. STEP 1: CBC WITH DIFFERENTIAL Always start with: ● Total WBC ● Differential count ● Absolute counts 👉 Why? Helps diagnose: ● ● ● ● Infection Leukemia Bone marrow disorders Inflammation Moderate 500–1000 Severe <500 Severe = life-threatening infection risk 🧠 Analogy Absolute count = actual number of soldiers. Relative count = only percentage. STEP 3: PERIPHERAL BLOOD SMEAR (PBS) STEP 2: ABSOLUTE COUNT (VERY HIGH YIELD) 📌 Relative % alone is misleading. Example: ● 70% neutrophils looks normal ● BUT if WBC = 20,000 → absolute neutrophilia 📌 Formula: 👉 ANC = WBC × % neutrophils 📌 ANC INTERPRETATION (Always memorize) Level ANC Mild neutropenia 1000–150 0 Used to detect: ● ● ● ● Blasts Immature cells Infection Leukemia 📌 Best area: Feathered edge 📌 Count 100 WBC manually. ⚠️ III. LEUKOPENIA (LOW WBC) 👉 Definition: Low WBC → increased infection risk. 📌 Causes (must memorize) ● Bone marrow failure ● ● ● ● ● Aplastic anemia Chemotherapy Radiation Viral infections Severe bacterial infections 🧠 Analogy: Army is weak → infection easily enters. ● ● ● ● ● ● Special: ● Emotional stress ● Burns ● Trauma 🔴 NEUTROPENIA (VERY HIGH YIELD) 👉 Definition: ANC <1500 👉 📌 Causes: Severe: ANC <500 → life-threatening infection ● ● ● ● Drugs Chemotherapy Viral infection Bone marrow suppression 🔥 IV. LEUKOCYTOSIS (HIGH WBC) 👉 Definition: WBC >10,000 📌 Causes (always tested) Infection Inflammation Stress Leukemia Steroids Splenectomy 📌 SHIFT TO LEFT (SUPER HIGH YIELD) 👉 Definition: Increased immature neutrophils (bands) in blood Occurs in: ● Acute bacterial infection ● Sepsis ● Inflammation 🧠 Analogy: Emergency → immature soldiers sent to battlefield. 📌 SHIFT TO RIGHT 👉 More mature neutrophils. Occurs when: ● Infection resolving. 🔬 V. DIFFERENTIAL COUNT INTERPRETATION (One of the most tested topics) 🔥 NEUTROPHILS 📌 Function: ● Phagocytosis ● First responders ● Acute inflammation 👉 Most common in bacterial infection 📌 Causes of neutrophilia: ● ● ● ● Bacterial infection Burns Exercise Stress 🔥 LYMPHOCYTES Function: Adaptive immunity. 📌 Causes of lymphocytosis: ● Viral infection ● Pertussis 👉 Exam trick: Viral = lymphocytes. 🔥 EOSINOPHILS Function: Parasites and allergy. 📌 Causes: ● Parasitic infection ● Allergy ● Asthma 👉 Exam favorite: Parasites → eosinophilia 🔥 BASOPHILS Function: Allergy and inflammation. Rare. Seen in: ● Myeloproliferative disorders. 🔥 MONOCYTES Exam trap! ⚡ VIII. CLINICAL PATTERN Function: Phagocytosis and cleanup. Seen in: RECOGNITION (SUPER HIGH YIELD) ● Chronic infection ● Tuberculosis ● Inflammation. 📊 VI. GRANULOCYTES VS AGRANULOCYTES (Memorize) Type Cells Granulocytes Neutrophils, Eosinophils, Basophils Agranulocytes Lymphocytes, Monocytes 🧠 VII. AGE DIFFERENCES (High yield!) ● Newborn: WBC high ● Children: lymphocyte predominance ● Adults: neutrophil predominance Infection WBC pattern Bacterial Neutrophilia Viral Lymphocytosis Parasitic Eosinophilia Allergy Eosinophilia Leukemia Blasts 🩺 IX. COMMON EXAM CASES 🧩 Case 1 (Appendicitis) Findings: ● Leukocytosis ● Neutrophilia 👉 Interpretation: Acute bacterial infection 🧩 Case 2 👉 High WBC + blasts Leukemia. 🚨 X. RED FLAGS (Consultant favorite) ✔ ✔ ✔ ✔ ✔ Severe neutropenia Blasts on smear Persistent leukocytosis Pancytopenia Left shift + toxic granulation. 🎯 XI. MOST COMMONLY ASKED QUESTIONS (UERM style) 1. 2. 3. 4. 5. 6. How to compute ANC? What is shift to left? Causes of neutrophilia? Viral vs bacterial infection? Differential count interpretation. Eosinophilia causes. 7. Leukocytosis vs leukopenia. 8. Absolute vs relative count. ⭐ FINAL ULTRA HIGH-YIELD SUMMARY 👉 CBC + differential = first step. 👉 Absolute counts are more important than %. 👉 Neutrophils = bacterial. 👉 Lymphocytes = viral. 👉 Eosinophils = parasites. 👉 ANC <500 = emergency. 👉 Left shift = acute infection. ✅ END OF DRAFT Would you like me to also add: ● ● ● ● ● ● 🔥 40–50 exam-style MCQs patterned after your UERM exams ⚡ Flowcharts (approach to leukocytosis and leukopenia) 🧠 Mnemonics and visual memory tricks 📊 Comparison tables 📚 Predicted long exam questions your prof may ask 🩺 Case-based simulations for viva Tell me what you want before I finalize. BLEEDING Here is your DRAFT high-yield cheat sheet for Bleeding Disorders, Hemostasis, and Coagulation based on your uploaded lecture + past exams. I highlighted what your prof commonly tests. Review first, then tell me what you want adjusted before I finalize. 🩸 BLEEDING DISORDERS Surgery 2 Long Exam Cheat Sheet (High-Yield + Must Knows) 🔥 BIG PICTURE (Start here) 🧠 SIMPLE ANALOGY Think of hemostasis like fixing a hole in a water pipe: 1. Primary hemostasis = sandbags → platelets stop bleeding quickly 2. Secondary hemostasis = cement → fibrin makes it strong 3. Tertiary hemostasis = cleaning crew → break the clot later If ANY step fails → bleeding or thrombosis. Hemostasis requires balance. Too much clot → thrombosis. Too little → bleeding. 🔥 MUST KNOW: 3 PHASES OF HEMOSTASIS (EXAM FAVORITE) 1️⃣ PRIMARY HEMOSTASIS (Platelets + vessel wall) 👉 Forms the initial platelet plug Key steps 1. 2. 3. 4. Vasoconstriction Platelet adhesion Platelet activation Platelet aggregation Platelets stick using vWF. 📌 vWF also carries Factor VIII. 2️⃣ SECONDARY HEMOSTASIS (Coagulation factors) 👉 Makes a stable fibrin clot Fibrin reinforces the platelet plug. Two pathways 🔴 EXTRINSIC (fast, in vivo) Starts first via Tissue Factor + Factor VII. 🔵 INTRINSIC (amplifies) PT/aPTT Factors VIII, IX, XI, XII. Factor X → thrombin → fibrin. TESTED) 3️⃣ TERTIARY HEMOSTASIS (Fibrinolysis) 👉 Breaks the clot. These help locate the problem first before ordering specific tests. 📌 PRIMARY HEMOSTASIS 1. Platelet count 2. Bleeding time 3. Platelet function tests tPA → plasmin → breaks fibrin. D-dimer = marker of fibrin breakdown. 🔥 CLINICAL CLUE TABLE (VERY HIGH-YIELD) Primary (Platelet) Abnormal 🔥 SCREENING TESTS (MOST COMMON Feature Normal Secondary (Coagulation) Bleeding type Mucosal Deep tissue Examples Epistaxis, petechiae Hemarthrosis Onset Immediate Delayed Platelet count ↓ or normal Normal Bleeding time tests platelet function and vascular integrity. ⚠️ Least reliable test → Bleeding time. 📌 SECONDARY HEMOSTASIS 1. PT 2. aPTT 3. Thrombin time 🔥 PT vs aPTT (ULTRA HIGH-YIELD) 🟢 PT (Prothrombin Time) 👉 Tests: Extrinsic + Common pathway Factors: ✔ VII ✔ I, II, V, X Used for: ✔ Warfarin monitoring ✔ Vitamin K deficiency ✔ Liver disease Vitamin K deficiency → prolonged PT first. 🔵 aPTT 👉 Tests: Intrinsic + Common pathway Factors: ✔ VIII, IX, XI, XII Used for: ✔ Hemophilia ✔ Heparin monitoring Hemophilia → prolonged aPTT. 🟡 Thrombin Time 👉 Tests: Conversion of fibrinogen → fibrin Detects fibrinogen abnormalities. 🔥 PATHWAY-BASED INTERPRETATION (FAVORITE IN EXAMS) Result Diagnosis ↑ PT only Factor VII, Vitamin K ↑ aPTT only Hemophilia ↑ PT + ↑ aPTT DIC, liver disease Normal PT/aPTT Platelet defect 🔥 MIXING STUDY (VERY COMMON QUESTION) Used when PT or aPTT is prolonged. 🧠 ANALOGY Add “normal blood” to see if the problem is: • Missing ingredient • Or poison (inhibitor) 🔥 COMMON DISORDERS + LABS (VERY HIGH-YIELD) Procedure Patient plasma + normal plasma → recheck. Interpretation ❌ ✔ Corrects → Factor deficiency No correction → Inhibitor 🧬 Hemophilia Deficiency: • Factor VIII or IX Examples: • Lupus anticoagulant • Factor VIII inhibitor Labs: ✔ Normal platelets ✔ Normal PT ✔ Prolonged aPTT 🔥 FIBRINOLYSIS 🧬 von Willebrand disease D-Dimer Marker of fibrin breakdown. Elevated in: ✔ DIC ✔ DVT ✔ PE ✔ Malignancy ✔ Surgery ✔ Pregnancy ⚠️ Not specific. Most common inherited bleeding disorder. Labs: ✔ Normal platelets ✔ ↑ Bleeding time ✔ ↓ Factor VIII 🧬 Liver disease Why? Liver makes clotting factors. Labs: ✔ ↓ Platelets ✔ ↑ PT + aPTT ✔ ↓ fibrinogen 🧬 DIC Consumption coagulopathy. 🔥 INDICATIONS FOR TESTING ✔ ✔ ✔ ✔ ✔ Suspected bleeding Before surgery Monitoring anticoagulants Liver disease DIC Labs: ✔ ↓ Platelets ✔ ↑ PT + aPTT ✔ ↑ D-dimer ✔ ↓ fibrinogen 🔥 HIGH-YIELD EXAM PEARLS 🔥 PRE-ANALYTICAL ERRORS ⭐ ALWAYS REMEMBER (FREQUENTLY TESTED) MOST common cause of lab errors. MUST KNOW: ✔ Correct blood:citrate ratio = 1:9 ✔ Sodium citrate tube ✔ No short draws Errors: • Hemolysis → falsely shortened tests • Wrong anticoagulant • Underfilled tube (Based on past UERM) ✔ ✔ ✔ ✔ ✔ Hemophilia → isolated aPTT Vitamin K → PT first DIC → everything abnormal Platelet problem → PT/aPTT normal Mixing study = deficiency vs inhibitor 🔥 QUICK DIAGNOSTIC APPROACH (LONG EXAM FAVORITE) Step 1 Platelet count. Step 2 PT + aPTT. Step 3 Mixing study. Step 4 Specific factor assay. 🔥 SHORTCUT MNEMONICS 🔥 COMMONLY TESTED QUESTIONS 1. 2. 3. 4. 5. 6. 7. 8. Least reliable test → Bleeding time Hemophilia lab pattern Mixing study interpretation DIC profile Vitamin K deficiency vWD profile Anticoagulant monitoring PT vs aPTT ⚡ MOST HIGH-YIELD CLINICAL TIP 👉 Hemostasis tests are NOT good at predicting bleeding risk. They help diagnose disorders, not predict bleeding. PT = 7 Only Factor VII. aPTT = 8,9,11,12. ✅ END OF DRAFT Would you like me to also add: Vitamin K = 1972 Factors II, VII, IX, X. 1. 2. 3. 4. 5. 🔥 40–50 exam-style MCQs patterned after UERM ⚡ Case-based long exam simulations 🧠 Flowchart for bleeding workup 📊 Master comparison tables of all bleeding disorders 🎯 Predicted questions your professor will ask Tell me what you want so I can finalize and optimize for your Surgery 2 long exam. TRANSFUSION Here is your high-yield, long-exam focused, Surgery 2 style cheat sheet based on your uploaded lecture + past exams. I highlighted frequently tested concepts, included simple explanations + analogies, and focused on clinical decision-making since that’s what your profs usually test at UERM. I will give the draft first so you can request edits or additions before I finalize. 🔥 TRANSFUSION MEDICINE CHEAT SHEET High-yield | Long exam | Surgery 2 | UERM pattern 🧠 BIG PICTURE (MOST COMMON LONG EXAM CONCEPT) 👉 Always use BLOOD COMPONENT THERAPY, not whole blood. 🧠 SIMPLE ANALOGY (remember this!) Think of blood like a pizza ● Whole blood = entire pizza ● Components = only the topping you need If you only need cheese → don’t order the whole pizza. ⭐ MUST KNOW #1: BLOOD COMPONENTS This is the MOST tested topic. 🩸 1. PACKED RED BLOOD CELLS (PRBC) Why? 📌 Function Because: Increase oxygen delivery. 1. 2. 3. 4. More targeted Less complications Less volume overload Safer 📌 According to your lecture: ● Use specific components like PRBC, plasma, platelets rather than whole blood to optimize therapy. 🍕: Used in: ● Trauma ● Surgery ● Anemia Lecture: ● PRBC increases RBCs after trauma, surgery, or anemia. 🔥 HIGH-YIELD INDICATIONS ✔ ✔ ✔ ✔ Hb < 7 g/dL Acute blood loss Symptomatic anemia CAD, CHF, COPD even if Hb >7 Lecture: ● Patients with symptoms or comorbidities may need transfusion even if Hb >7. ⚠️ LONG EXAM PEARL ● PRBC stored 42 days in refrigerator. 🧠 ANALOGY PRBC = oxygen delivery truck 🚚 🩸 2. FRESH FROZEN PLASMA (FFP) 📌 Function Replace clotting factors. Lecture: 👉 Do NOT transfuse based on Hb alone. ● Correct coagulation factor deficiency. Assess: ● Symptoms ● Functional status ● Comorbidities Lecture: ● Must evaluate symptoms, physiologic status, and comorbidities. 📌 Storage ● 42 days refrigerated Lecture: 🔥 HIGH-YIELD INDICATIONS ✔ ✔ ✔ ✔ ✔ ✔ Bleeding + prolonged PT and aPTT DIC Liver disease with bleeding Massive transfusion Warfarin reversal Plasma exchange (TTP, HUS) Lecture: ● Used for multiple factor deficiencies and anticoagulation reversal. ❌ NOT USED FOR Prevent or treat bleeding from low platelets. 🚫 Platelet disorders (Glanzmann) Lecture: → Need platelets. ● Treat bleeding due to low platelet levels. Past exam: ● FFP not used in Glanzmann thrombasthenia. 📌 Volume 🔥 HIGH-YIELD INDICATIONS ✔ Platelets < 10k (prophylaxis) ✔ <50k + surgery ✔ Active bleeding ● 200–250 mL ❌ NOT used in: 📌 Storage ● Coagulation factor deficiency ● 1 year frozen 📌 Storage Lecture: ● Stored for 1 year in freezer. ● 3–5 days at room temperature 🧠 ANALOGY FFP = repair workers fixing leaks in pipes Lecture: 🛠 🩸 3. PLATELET CONCENTRATE 📌 Function ● Shortest shelf life. 🔥 EXAM FAVORITE! 🧠 ANALOGY 🧱 Platelets = construction workers They build the first plug in bleeding. 🧴 🩸 4. CRYOPRECIPITATE 📌 Contents (VERY HIGH YIELD) ✔ ✔ ✔ ✔ Fibrinogen Factor VIII vWF Factor XIII Lecture: ● Contains fibrinogen, vWF, FVIII, FXIII. 🔥 INDICATIONS ✔ ✔ ✔ ✔ Hypofibrinogenemia Hemophilia A von Willebrand disease DIC with low fibrinogen 📌 Volume ● Smallest volume (10–15 mL) Cryo = glue Helps blood stick and clot. ⭐ MUST KNOW #2: BLOOD PRESERVATIVES (COMMON MCQ) 📌 Components Componen t Function Citrate prevents clotting Phosphate maintains pH Dextrose food Adenine ATP Saline prevent hemolysis Lecture: ● Adenine provides ATP to RBCs. 🔥 Very commonly asked! Lecture: ● Cryo has smallest volume. 🧠 ANALOGY ⭐ MUST KNOW #3: STORAGE LESION (VERY HIGH YIELD) Changes in stored blood ✔ ✔ ✔ ✔ ✔ ✔ ↑ Potassium ↑ Ammonia ↑ Lactic acid ↓ pH ↓ glucose RBC become spherocytes Lecture: ● Potassium increases due to Na-K pump failure. ⭐ MUST KNOW #4: TRANSFUSION REACTIONS 🔥 MOST COMMON 👉 Febrile non-hemolytic reaction Lecture: ● Most common transfusion reaction. 🔥 CLINICAL IMPORTANCE Cause: Use fresh blood in: ✔ Neonates ✔ Exchange transfusion ✔ Liver disease Prevention: ✔ Leukocyte filters Lecture: 🔥 MOST DANGEROUS ● Fresh blood recommended in newborn exchange and cirrhosis. 🧠 ANALOGY Stored blood = expired food The longer it sits, the worse it becomes. ● Cytokines from WBC 👉 Acute hemolytic transfusion reaction Cause: ● ABO incompatibility Lecture: ● Most life-threatening. Symptoms: ✔ Fever ✔ Chills ✔ Hemoglobinuria ✔ Hypotension Removes: 🔥 SECOND MOST COMMON Used in: ✔ Severe allergic reaction ✔ IgA deficiency 👉 Allergic reaction Cause: ● Antibodies ● Plasma proteins Past exam: ● Washing removes antibodies. ● Recipient antibodies vs donor proteins. ⭐ MUST KNOW #5: MANAGEMENT OF TRANSFUSION REACTION 👉 FIRST STEP: STOP transfusion Past exam: ● Stop immediately and assess. ⭐ MUST KNOW #6: SPECIAL BLOOD ✔ Irradiated blood Kills lymphocytes → prevents GVHD. Used in: ✔ Immunocompromised ✔ Leukemia ✔ Bone marrow transplant Past exam: ● Indicated in leukemia. PRODUCTS ⭐ MUST KNOW #7: EMERGENCY ✔ Washed RBC 🔥 GOLD STANDARD TRANSFUSION 👉 O negative PRBC 🔥 UERM FAVORITE Washed O PRBC = safest in emergency Past exam: ⭐ MUST KNOW #9: WHEN NOT TO TRANSFUSE 🚫 Asymptomatic 🚫 Hb acceptable 🚫 Mild anemia Lecture: ● Best emergency transfusion. ⭐ MUST KNOW #8: ABO + CROSSMATCH Purpose ● Asymptomatic patients may not require transfusion. 🔥 ULTRA HIGH-YIELD SUMMARY (LAST MINUTE) Detect unexpected antibodies. Lecture: ● Final check before transfusion. Phases 1. Immediate spin → ABO 2. 37°C → enhance 3. AHG → IgG antibodies ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ Use components, not whole blood PRBC for anemia FFP for factor deficiency Platelets for platelet problem Cryo for fibrinogen Febrile reaction most common Acute hemolytic most dangerous Platelets shortest shelf life Adenine provides ATP Fresh blood for neonates Stop transfusion first 📊 ULTRA HIGH-YIELD COMPARISON TABLE Componen t Used for Shelf life Key exam point PRBC anemia 42 days oxygen FFP coagulation 1 year warfarin reversal Platelets low platelets 3–5 days shortest Cryo fibrinogen 1 year glue 📌 LIKELY LONG EXAM QUESTIONS (BASED ON PAST TRENDS) 1. 2. 3. 4. 5. 6. 7. Trauma + bleeding → what to transfuse? Cirrhosis + bleeding → FFP Platelet disorder → platelets Warfarin reversal → FFP Neonatal exchange → fresh blood Febrile reaction → leukocyte filters Emergency transfusion → O negative If you want, I can also add: ✔ 40–50 UERM-style MCQs ✔ Case-based simulations ✔ Step-by-step transfusion algorithm ✔ Massive transfusion protocol ✔ Neonatal transfusion pearls ✔ ABO + Rh quick recall charts ✔ Flowcharts for bleeding Just tell me what you want next before I finalize.