Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Surgery Review 1
SR 1: Cell bio, hematology, transfusion, immunology,infection, abx, pharmacology
| Question | Answer |
|---|---|
| What increases membrane fluidity? | Cholesterol |
| Adhesion molecules which anchor cells to each other and to the extracellular matrix | Desmosomes and hemidesmosomes |
| Cell-to-cell occluding junctions that form an impermeable barrier (i.e. epithelium) | Tight junctions |
| Phases of the cell cycle | G1 (most variable – determines cell cycle length), S (DNA replication), G2, M |
| What phase of the cell cycle is most sensitive to radiation therapy? | M - mitosis |
| Which phase of the cell cycle do growth factors affect? | G1 |
| What are the phases of mitosis? | Prophase (spindle formation) Metaphase (chromosome alignment) Anaphase (chromosomes pulled apart) Telophase (separate nucleus re-forms around each set of chromosomes) |
| The outer membrane of the nucleus of a cell is continuous with what? | rough endoplasmic reticulum |
| Where do steroid hormones bind their receptors? | cytoplasm |
| Where do thyroid hormones bind their receptors? | nucleus |
| What are the purines? | guanine and adenine |
| What are the pyrimidines? | cytosine, thymidine (ony in DNA), uracil (only in RNA) |
| What is the process by which mRNA is used as a template by ribosomes for synthesis of protein? | translation |
| What cell subunits read mRNA, then bind appropriate tRNAs that have amino acids, and eventually make proteins? | ribosomes |
| What are the products of glycolysis? | 1 glucose molecule generates 2 ATP and 2 pyruvate molecules |
| What are the products of the Krebs cycle? | 2 pyruvate molcules form NADH and FADH2 which enter the electron transport chain to create ATP |
| Overall, how many ATP are formed from one glucose molecule? | 36 |
| What are fats and lipids not available for gluconeogenesis? | acetyl CoA (breakdown product of fat metabolism) cannot be converted back to pyruvate |
| What is the function of the rough endoplasmic reticulum? What organ has an increase in this? | synthesizes proteins that are exported (increased in pancreatic acinar cells) |
| What is the function of the smooth endoplasmic reticulum? What organ has an increase in this? | lipid/steroid synthesis and detoxifies drugs (increased in liver and adrenal cortex) |
| What are the three initial responses to vascular injury? | vasoconstriction, platelet adhesion, and thrombin generation |
| What combines with platelets to form the platelet plug? | fibrin |
| What are the functions of thrombin? | Converts fibrinogen to fibrin and fibrin split products, activates factor V, VII, and activates platelets |
| What are the functions of antithrombin III? | Binds and inhibits thrombin, inhibits factors IX, X, and XI |
| What are the functions of protein C and protein S? | Protein C degrades factors V, VIII, and fibrinogen; proteins S acts as a cofactor for protein C |
| What is the function of TPA? | tissue plasminogen activator – released from endothelium and converts plasminogen to plasmin |
| What is the function of plasmin? | Degrades factors V, VIII, fibrinogen, and fibrin causing a loss of the platelet plug |
| Which clotting factor has the shortest half life? | factor VII |
| What is the only factor not synthesized in the liver? | factor VIII – synthesized in endothelium |
| What are the vitamin K dependent factors? | II, VII, IX, X, protein C + S |
| How long after administration does vitamin K take effect? What about FFP? | Six hours for vit K, FFP is immediate and lasts 6 hours |
| What is the normal half-life of RBCs? Platelets? PMNs? | RBCs – 120 days platelets – 7 days PMNs – 1-2 days |
| What factors does PT measure? | II, V, VII, and X and fibrinogen |
| What factors does PTT measure? | All factors except VII and XIII |
| What is the most common cause of surgical bleeding? | incomplete hemostasis |
| What are the types of Von Willebrand’s disease? | Types I+III have a reduced quantity of vWF type II has a defect in vWF itself (qualitatively poor) type I is most common but type III is most severe |
| What is the function of vWF? | Links GpIb receptors on platelets to collagen and binds factor VIII |
| What tests for Von Willebrand’s disease? | Ristocetin test |
| What is the only inherited coagulopathy with long bleeding time? | Von Willebrand's Disease (autosomal dominant) |
| What is the treatment for a hemophiliac joint? | ice, range of motion, factor VIII concentrate or cryoprecipitate if necessary – NO aspiration |
| What is the treatment for Von Willebrand’s Disease? | Types I+III – cryo, DDAVP, or conjugated estrogens type II cryo only |
| Why does a child with hemophilia not bleed during his circumcision? | Factor VIII crosses the placenta |
| What is the pathophysiology of Glanzmann’s thrombocytopenia? | GpIIb/IIIa receptor deficiency of platelets. Decreased platelet aggregation. Fibrin normally links Gp IIb/IIIa receptors |
| What is the pathophysiology of Bernard Soulier syndrome? | GpIb receptor deficiency of platelets. Decreased adherence of exposed collagen. vWF normally links Gp Ib to collagen |
| What is the mechanism of clopidogrel (Plavix)? | ADP receptor antagonist |
| What antibiotics can bind platelets, thus increasing bleeding times? | PCNs and cephalosporins |
| What is the mechanism of cilostazol (Pletal)? | type 3 phosphodiesterase inhibitor increasing cAMP and inhibiting platelet aggregation |
| What is the mechanism of pentoxifylline (Trental)? | nonselective phosphodiesterase inhibitor increasing cAMP and inhibiting platelet aggregation; also improves red blood cell deformability |
| What is the treatment of HIT (heparin induced thrombocytopenia)? | stop heparin, argatroban, hirudin, or dextran to anticoagulate |
| What are platelet goals in a thrombocytopenic patient in the perioperative period? | Keep plateltes >50,000 before surgery and >20,000 after surgery |
| What are the most common inherited thombophilias? | Factor V Leiden, Prothrombin mutation (GP20210), Hyper-homocysteinemia |
| What is the pathophysiology of factor V Leiden? | Defect on factor V which causes resistance to activated protein C |
| What is the treatment of hyperhomocysteinemia? | folic acid and B-12 |
| How is antiphospholipid syndrome diagnosed? | Test for lupus anticoagulant, prolonged PTT (not corrected with FFP), positive Russel viper venom time, false positive RPR for syphilis |
| How does cardiopulmonary bypass cause a hypercoagulable state? | Activates factor XII (Hageman factor) |
| What are the indications for an IVC filter? | Patients with contraindication for anticoagulation, PE while on anticoagulation, free floating femoral/iliofemoral/IVC DVT, previous pulmonary embolectomy |
| What is the mechanism of warfarin? | Prevents vitamin K dependent decarboxylation of glutamic residues on clotting factors |
| How do sequential compression devices work? | Improve venous return and also induce fibrinolysis by releasing tPA |
| What drug reverses heparin? | Protamine |
| What is the most common complication of heparin reversal with protamine? | Hypotension |
| What are the complications of long term heparin? | Osteoporosis and alopecia |
| What are the symptoms of a protamine reaction? What patients are most susceptible? | Hypotension, bradycardia, decreased heart function. Protamine cross reacts with NPH insulin or previous exposure, but 4-5% of all patients will have a reaction |
| What is the mechanism of Argatroban? | Direct thrombin inhibitor |
| What are two common anti-fibrinolytics and their mechanism of action? | Aminocaproic acid (Amicar) – inhibits fibrinolysis by inhibiting plasmin Aprotinin (Trasylol) – inhibits fibrinolysis by inhibiting plasminogen activation |
| What are indications for giving antifibrinolytics? | DIC, overdose of tPA, or excessive bleeding after cardiopulmonary bypass |
| What laboratory value is followed when given thrombolytics? | fibrinogen levels - <100 associated with increased risk and severity of bleeding |
| What are absolute contraindications to thrombolytic use? | Active internal bleeding recent CVA (<2 months) intracranial pathology |
| What blood products do not carry any risk of HIV or hepatitis? | albumin and serum globulins |
| What are indications for using CMV-negative blood? | Low birth weight infants, transplant patients (bone marrow or solid organ) |
| What is the number 1 cause of death from transfusion reaction? | Clerical error leading to ABO incompatibility |
| What are the communicable disease risks of a blood transfusion? | CMV is highest Hep C 1:30-150,000 HIV 1:500,000 |
| What is an effect of stored blood? | Decreased 2,3-DPG – left shift in oxygen disassociation curve causing an affinity for oxygen |
| What are the symptoms of an acute hemolysis reaction? What is the treatment? | Back pain, fever, chills, tachycardia, hemoglobinuria, can lead to ATN, DIC, and/or shock. Treat with fluids, diuretics, HCO3-, pressors, and histamine blockers (Benadryl) |
| What is the most common transfusion reaction? What is its cause? | Febrile nonhemolytic transfusion reaction caused by recipient antibody reaction against WBCs in donor blood |
| What is the cause of anaphylaxis during a blood transfusion? | IgG against IgA in IgA-deficient recipient |
| What is the cause of urticaria during a blood transfusion? | Usually a reaction against plasma proteins or IgA in the transfused blood |
| What is the cause of transfusion related lung injury (TRALI)? | Antibodies to recipients WBCs, clot in pulmonary capillaries |
| What is the most common bacterial contaminent in blood? | GNRs (usually E. coli) |
| What causes B cell maturation into plasma cells? | IL-4 |
| What causes maturation of cytotoxic T cells? | IL-2 |
| What is the function of cytotoxic T cells? | recognizes and attacks non-self-antigens attached to MHC class I receptors (e.g. viral gene products) |
| What is used to test cell-mediated immunity? | Intradermal skin test |
| What infections are associated with defects in cell mediated immunity? | intracellular pathogens (TB, viruses) |
| What cells are MHC class I present on? What about MHC class II? | MHC class I are present on all cells, MHC class II are present on B cells, monocytes, and antigen presenting cells |
| What cells are part of the bodies immunosurveillance for cancer? | Natural killer cells |
| What type of hypersensitivity reaction is IgE mediated with release of histamine, serotonin, and bradykinin in response to major basic protein from eosinophils, which have IgE receptors for the antigen | Type I (allergic reaction) |
| What type of hypersensitivity reaction is characterized by IgG or IgM reacting with cell-bound antigens (ABO blood type incompatibility, ITP, Graves’, myasthenia gravis)? | Type II |
| What type of hypersensitivity reaction is characterized by immune complex deposition (serum sickness, rheumatoid arthritis, SLE)? | Type III |
| What type of hypersensitivity reaction is a delayed-type hypersensitivity – antigen stimulation of previously sensitized T cells (TB skin test, contact dermatitis)? | Type IV |
| When do you give tetanus immune globulin? | Patient has not been immunized or status unknown. If it has just been <5 years since last booster, only need to give tetanus toxoid |
| What can enhance immune function in critical illness? | arginine |
| What is the most common aerobic and anaerobic bacteria in the colon? | Aerobic – E.coli; Anaerobic – bacteroides fragilis |
| What is the pathophysiology of gram negative sepsis? | Ednotoxin (lipopolysaccharide A) is released from bacteria, which triggers release of TNF-alpha (from macrophages), activating completent and coagulation cascades |
| What is the first sign of early gram negative sepsis? | hyperglycemia |
| What are indications for antibiotic treatment of an abscess? | Diabetes, cellulitis, fever, leukocytosis, or bioprosthetic hardware |
| What are the wound infection rates of the 4 types of wounds? | Clean (hernia) – 2% Clean-contaminated (colon resection with prep) – 3-5% Contaminated (gunshot wound to bowel) – 5-10% Gross contamination (abscess) – 30% |
| What is the most common organism overall in surgical wound infections? | Staphylococcus aureus |
| What are risk factors for wound infections? | Long operation, hematoma or seroma, age, malnutrition, immunosuppresion, chronic disease (COPD, renal failure, liver failure, DM) |
| What two infections can present within hours post-operatively? | Clostridium perfringens and beta-hemolytic strep (produce exotoxins) |
| What is the leading cause of infectious death after surgery and what organisms are most commonly involved? | Nosocomial pneumonia – S. aureus and pseudomonas |
| What are the four intraabdominal abscess locations? | sub-diaphragmatic sub-hepatic inter-loop pelvic |
| What infection can present with myonecrosis and gas gangrene associated with farming injuries? | Clostridium perfringens |
| What organism presents with pulmonary symptoms commonly and can cause tortuous abscesses in cervical, thoracic, and abdominal areas? Treatment? | Actinomyces – drainage and penicillin G |
| What fungal infection presents with pulmonary and CNS symptoms? What is the treatment? | Nocardia – drainage and sulfonamides (Bactrim) |
| What fungal infection predominates in the Ohio and Mississippi river valleys and commonly presents with pulmonary symptoms? Treatment? | Histoplasmosis – amphotericin for severe infections |
| What is the most common cause for laparotomy in HIV patients? | Opportunistic infections (CMV colitis – pain, bleeding, or perforation - most common), neoplastic disease is second most common |
| What are the most common reasons of GIB in HIV? | Lower > upper; UGIB – Kaposi sarcoma, lymphoma; LGIB – CMV, bacterial, HSV |
| What is the treatment for a brown recluse spider bite? | Dapsone, but may need debridement later |
| What is the dominant organism in human, cat, and dog bites? | Human – Eikenella – can cause permanent joint injury; Cat/dog – Pasteurella multocida |
| What is the treatment for peritoneal dialysis catheter infections? | intraperitoneal vancomycin and gentamicin, amphotericin for fungal infections; intraperitoneal heparin may help; remove of catheter if infection lasts 4-5 days |
| What is endotoxin? Where does it come from? | Lipopolysaccharide A from gram negative bacteria |
| What is the mechanism of penicillins, cephalosporins, and carbapenems? | Inhibitors of cell wall synthesis |
| What is the mechanism of aminoglycosides? | Inhibitors of 30s ribosome and protein synthesis – irreversible binding and bactericidal |
| What is the mechanism of tetracycline, and linezolid? | Inhibitors of 30s ribosome and protein synthesis – bacteriostatic |
| What is the mechanism of erythromycin, clindamycin, and chloramphenicol? | Inhibitors of 50s ribosome and protein synthesis |
| What is the mechanism of quinolones? | DNA gyrase inhibition |
| What is the mechanism of rifampin? | RNA polymerase inhibition |
| What is the mechanism of metronidazole (Flagyl)? | Produces oxygen free radicals that breakup DNA |
| What is the mechanism of sulfonamides? | PABA analogue, inhibit purine synthesis |
| What is the mechanism of penicillin resistance? | plasmids for beta-lactamase |
| What is the mechanism of vancomycin? What is the mechanism of it's resistance? | Inhibits cell wall synthesis; Altered cell wall (unable to bind) |
| What is the mechanism of amphotericin | binds sterols to alter fungal cell wall |
| What is the most common mechanism of antibiotic resistance? | transfer of plasmids |
| What is the mechanism of MRSA resistance? | mutation in cell wall binding protein |
| What is the mechanism of aminoglycoside (gentamicin, tobramycin) resistance? | Resistance due to modifying enzymes leading to decreased active transport |
| What organisms are carbapenems least effective against? | MEPP – MRSA, enterococcus, proteus, and pseudomonas |
| What is a side effect of carbapenems? | Seizures |
| What are side effects of vancomycin? | Redman syndrome (histamine release), nephrotoxicity, ototoxicity |
| What are side effects of aminoglycosides? | Reversible nephrotoxicity, irreversible ototoxicity |
| What are some side effects of Bactrim? | teratogenic, Stevens-Johnson syndrome, hemolysis in G6PD-deficiency |
| What are the side effects of metronidazole (Flagyl)? | disulfiram-like reaction, peripheral neuropathy |
| What antiviral is used for HSV infections? | Acyclovir |
| What antiviral is used to treat CMV infections? | Ganciclovir |
| Which antibiotics can bind platelets and increase bleeding times? | PCNs and cephalosporins |
| What drug can displace unconjugated bilirubin in newborns? | Sulfonamides |
| What is the difference between 1st order and 0 order kinetics? | 1st order kinetics – drug is eliminated proportional to dose; 0 order kinetics – constant amount of drug is eliminated regardless of dose |
| What is the fraction of unchanged drug reaching the systemic circulation? | Bioavailability |
| What is the difference between polar (or ionized) and nonpolar drugs? | Polar drugs are more water soluble and more likely to be eliminated in unaltered form, whereas nonpolar drugs are more likely to be metabolized before excretion |
| What is the mechanism of allopurinol? | Xanthine oxidase inhibitor, blocks uric acid formation from xanthine; used for overproducers |
| What is the mechanism of Probenacid? | Increases renal secretion of uric acid; used for undersecreters |
| What is the mechanism of statins? | HMG-CoA reductase inhibitors |
| What are potential side effects of statins? | Liver dysfunction, rhabdomyolysis |
| What is a potential side effect of promethazine (Phenergan)? | Tradive dyskinesia (inihibits dopamine receptors) |
| What is the mechanism of ondansetron (Zofran)? | serotonin receptor inhibitor – antiemetic |
| What is the mechanism of digoxin? | Inhibits Na/K ATPase to increase myocardial calcium |
| What is the effect of digoxin? | Slows AV conduction, inotrope but decreases O2 consumption |
| What is the best single agent shown to decrease mortality in CHF? | ACE inhibitors |
| What are some potential side effects of procainamide? | Lupus-like syndrome, pulmonary fibrosis, and torsades |
| What is a common side effect of gadolinium? | nausea |
| What are the symptoms of ASA poisoning? | tinnitus, headaches, N/V, respiratory alkalosis and metabolic acidosis |
| What is the treatment for an acetominophen overdose? | N-acetylcysteine |
| What is the mechanism and effect of reglan (metoclopramide)? | Dopamine receptor blocker - Increases LES tone and gastric motility |
Created by:
jclanton82
Popular Surgery sets