Weekly TrueLearn Questions Flashcards
Describe the Cushing Reflex
What are common signs of aortic regurgitation?
High pitch, decrescendo diastolic murmur heard best at left sternal border. Widening pulse pressure.
During which of the phases of a cardiomyocyte action potential are Ca++ channels open?
During phase 2 – K Efflux and Ca++ influx make the plateau phase
What occurs at point C in this pressure-volume loop of the left ventricle?
Isovolumetric contraction ceases as the aortic valve opens and blood leaves the left ventricle
What is the most likely diagnosis of a patient with worsening DOE and bilateral hilar adenopathies on CT? What pulmonary function testing will be abnormal?
Sarcoidosis, a restrictive lung disease will cause a decrease in residual volume (The amount of air left in the lungs after maximum forceful exhalation)
Describe the effects of hypoxia on peripheral vasculature and on pulmonary vasculature
Peripheral vasculature vasodilate while pulmonary vasculature vasoconstricts (Hypoxic Pulmonary Vasoconstriction, or HPV)
How is Minute Volume calculated?
Tidal Volume x Body weight in Kg x Respiration Rate
What is the most common genetic deficiency in patienets with emphysema?
Alpha-1 antitrypsin deficiency.
Causes unnopposed elastase activity, decreasing elastin activity and panacinar emphysema. Look for lung hyperinflation on CXR!
What is the primary differentiation between transudative and exudative pleural effusion?
Exudative pleural effusion is d/t inflammatory processes. The space between endothelial cells allow for large molecules to pass into the pleural space. Proteins, LDH, cholesterol will all be found in that fluid where it will be less present in transudative pleural effusions.
Patients with a history of psychotic episodes and an acute presentation of hyperthermia, HTN, tachycardia and tachypnea with dark red urine are likely experiencing a side effect of which type of medication?
This patient is likely suffering from neuroleptic malignant syndrome (NMS) which is mostly likely d/t typical antipsychotics such as Fluphenazine, Haloperidol or Resperidone.
Treatment is Dantrolene
Histologically and physiologically, describe both type 1 and type 2 pneumocytes
Type 1: These are simple squamous cells which make up the structural integrity of the alveoli. They are also necessary for the process of gas exchange
Type 2: These are cuboidal cells interspersed w/in the alveoli. They contain lamellar bodies which contain proteins necessary in the production of surfactant.
A patient that presents with calcinosis (calcinosis cutis), Reynaud phenomenon, esophageal hypomotility, sclerodactyly and telangiectasias. What autoantibody is most likely present in this patient?
CREST Syndrome, a constellation of symptoms associated with systemic sclerosis, is characterized by the presence of anti-centromere autoantibodies.
CREST -
(C)alcinosis
(R)eynaud Phenom.
(E)sophageal hypomotility
(S)clerodactyly
(T)elangiectasias
What are the symptoms and what autoantibody is present in Sjogren Syndrome?
Anti-Ro autoantibody
It presents with dry mouth and eyes, sticky oral mucosa, filliform papillae atrophy and enlargement of salivary and lacrimal glands
What diseases are associated with a malar (butterfly) rash?
SLE is the big one. But don’t let it fool you to not think of – Mixed tissue connective disease, cellulitis, rosacea and dermatomyositis
What is the mechanism of action of Gemfibrozil, Fenofibrate and Colfibrate?
Fibrate medications enhance the activity of lipoprotein lipase, cleaving free fatty acids from VLDL and promoting the uptake of them into adipose tissue, decreasing the circulating amount.
What is the primary medication used for a patient w/ Tetralogy of Fallot?
Phenylephrine, an alpha-1 agonist is used, followed by Propranolol.
What medication can be used to treat both BPH and HTN?
Alpha-1 adrenergic antagonists Terazosin and Doxazosin
Where are Alpha-1 and Alpha-2 receptors located?
Alpha-1 receptors are found in the peripheral vasculature and the smooth mm of other organs, including GI tract
- Stimulation = vasoconstriction
Alpha-2 receptors are found in the CNS and regulate release of Norepinephrine
- Stimulation = decreased amounts of neurotransmitters (NE)
Why is the EF preserved in a patient w/ HFpEF?
Both end diastolic LV volume AND stroke volume are reduced, maintaining the ejection fraction
What biomarker will be elevated w/ HFpEF but not with HFrEF?
Natriuretic peptide, which is released when the LV wall is stretched in HFpEF
What is the mechanism of action of Celecoxib?
Celecoxib is a COX-2 selective inhibitor, unlike NSAIDs which are non-specific COX inhibitors.
What is the most common cause of atypical and typical pneumonia?
Atypical - Mycoplasma Pneumoniae
Typical - Streptococcus Pneumoniae
What is the most common causative agent of pulmonary infections in a patient w/ Cystic Fibrosis?
Pseudomonas Aeruginosa
A purple gram staining organism is isolated from sputum of a patient w/ fever, dyspnea and a productive cough. Patient has a history of alcoholism. What is the most likely organism?
DON’T LET THE ALCOHOLISM FOOL YOU. Staph aureus is the most likely organism that is gram negative (purple) while Klebsiella Pneumoniae is gram positive (red)
Where do RNA viruses duplicate?
Within the cytoplasm of the infected cell
What is the Opsonization process and what antibody does it most use?
Opsonization is an immune process which marks pathogens with an Opsonin for phagocytosis. The most used antibodies are IgG.
Which fungus colonizes the lungs of up to 10% of corticosteroid-dependent asthmatics?
Aspergillosis will lead to allergic bronchopulmonary aspergillosis, resulting in frequent recurring asthma attacks, increased serum IgE concentrations and eosinophilia.
Name a virulence factor for a gram-positive cocci, catalase negative, alpha-hemolytic and optochin sensitive organism
Strep pneumo has a polysaccharide capsule virulence factor
Explain the Gs pathway and medications that activates it
Hormone –> GPCR receptor –> Gs protein –> Stimulates Adenylyl Cyclase –> (ATP) –> (PPi + cAMP) –> cAMP activates PKA –> Protein Kinase A exerts its effect on bio tissue
Epinephrine is a principal drug that stimulates this pathway
What effect does a bronchodilator have on a patient w/ an obstructive airway disease? How about corticosteroids?
Both will decrease airway oobstruction and increase FEV1. Steroids are slow acting because they work primarily on inflammation, whereas a bronchodilator will almost immediately increase air flow.