Pulmonary Flashcards
Pulmonary Hypertension
Normal PAP = 10-14
PAH = >25
Idiopathic or Primary PAH
- heritable
- often due to an inactivating mutation in BMPR2 (this gene normally inhibits vascular smooth muscle)
- a mutation in BMPR2 allows for excessive VSM proliferation leading to increased resistance
- associated with HIV and Kaposi sarcoma
Pg 614 Treatments Bosentan and Androsentan - competitively antagonize the endothelin receptor to decrease PVR Prostaglandins Sildenafil Dihydropyridine CCB (nifedipine)
When a lung collapses the intrathoracic volume increases due to chest wall expansion
FRC
- at FRC airway and alveolar pressures are at 0
- and intra pleural pressure is negative (prevents pneumothorax)
- PVR is at minimum
- Compliance = change in lung volume for a given change in pressure, decrease in pulmonary fibrosis, pneumonia, pulmonary edema, increase in emphysema, normal aging.
Cyanide Poisoning
Give patient nitrites
- converts hemoglobin to methemoglobin and allows for increased removal of cyanide by methemoglobin
- methemoglobin has an increased affinity for cyanide
Methemoglobinemia
- nitrites and nitrates
- anti malarial drugs
- dapsone
- sulfonamides
- local anesthetic
- metoclopramide
Treatments
- methylene blue
- vitamin C
- Cimetidine gradually lowers methemoglobin levels
Clinical presentation
- cyanosis
- chocolate colored blood
Carboxyhemoglobin
Hemoglobin bound to CO in place of O2
- causes a decrease in oxygen binding capacity with a left shit in the oxygen dissociation curve which decreases O2 unloading in tissues
Treatment = hyperbaric O2 and 100% O2
Oxygen Content of Blood
Pg 605
COPD
- decreased arterial PO2
- physiologic shunt –> decreased O2 extraction ratio
- decreased blood O2 content
Excercise/activity
- No change in arterial O2 content
- decreased venous PO2 due to increased O2 demand and increased oxygen extraction by tissues
Alveolar Gas Equation
606
Normal A-a gradient = 10-15mmHg
PAO2 - PaO2
Anemia can occur due to uterine fibroids = causes excessive uterine bleeding
Cyanosis occurs when deoxygenated Hb is >5g/dL
See Picture
High Altitude
- Barometric pressure is decreased
- decreased PaO2 and PAO2
Compensation
- acute increase in ventilation ==> causes you to blow off more CO2 ==> increased bicarbonate excretion
- respiratory alkalosis with metabolic acidosis compensation
- increase Erythropoietin => Increase Hb and hematocrit (RBC)
- increased 2,3-BPG ==> to allow unloading of oxygen to tissues
- increased mitochondria, increased O2 efficiency
- Treatment = Acetozolamide to help with altitude sickness
Pg 607
Acute mountain sickness symptoms
- headache
- fatigue
- acute cerebral edema due to hypoxia induced vasodilation
- acute pulmonary edema = hypoxia induced local vasoconstriction which increases capillary pressure which forces fluid out the vasculature and into the lungs
Chronic mountain sickness
- Increased RBC mass and hematocrit
- increased blood viscosity and decreased tissue blood flow
- elevated PAP
- Right heart enlargement
- Peripheral artery pressure
- Congestive Heart failure
Aviation and Space Flight
The effect of gravitational force on the body on a flight
- G-force moves blood
- Positive G (pushes you into chair) = Head–> Feet
Visual blackouts occur at about 4-6Gs because there insufficient blood return to the heart and insufficient pumping go blood to brain
- Negative G = Feet –> Head
Space G-force
- G-force that is achieved during a spacecraft liftoff = 8-9Gs
How is the body affected at 0 gravity?
- decreased blood volume
- decreased RBC mass
- decreased muscle strength/work capacity
- decreased maximum cardiac output
- loss of calcium and phosphate resulting in loss of bone mass
Deep Sea and Hyperbaric Medicine
Nitrogen Narcosis
- Nitrogen dissolves into neural membranes which causes reduced neuronal excitability
- diver becomes jovial/careless and become drowsy and lose strength coordination
Decompression sickness = the bends = caisson disease
- when you are underwater nitrogen disolves in the blood
- when you come up to sea level to quickly the gases begin to escape the dissolve state and form actual bubbles that can occlude the blood vessels
- symptoms = pain in joints and muscles of arms and legs, neurological problems (dizziness, paralysis, syncope) , chokes (air bubbles occlude lung capillaries resulting shortness of breath, pulmonary edema, death)
- Treatment = hyperbaric therapy
Hyperbaric oxygen uses
- decompression sickness
- arterial gas emboli
- carbon monoxide poisoning
- Gas gangrene
- osteomyelitis
Asthma
Curshmanns Spiral = shed epithelium forms whirled mucus plugs
Charcot Leyden crystals = eosinophilic, hexagonal, double pointed, needle like crystals formed from breakdown of eosinophils in sputum
Lines of Zahn
- interdigiting areas of pink
- platelets, fibrin and red RBCs found only in thrombi formed before death
- help distinguish pre and postmortem thrombi
READ STEP BOOK
611-613
And DRUGS of Respiratory
Sarcoidosis
- bilateral hilar lymphadenopathy
- noncaseating granulomatous
- increased ACE and Vitamin D due to increased 1-alpha hydroxylase
Drugs that can cause Restrictive Lung Disease
Bleomycin
Busulfan
Amiodarone
Methotrexate
Lung Cancer
Small Cell (oat cell) lung carcinoma
Non-Small cell carcinoma
- adenocarcinoma - most common type of lung cancer. Usually found on pre-existing lesions. Most common lung cancer found in non smokers and females. CEA positive
- squamous cell carcinoma
- large cell lung cancer
617-619
Pneumonia
Pg 616
Common cause of pneumonia in immunocompromised = Pneumocystis jiroveci
Most common cause of atypical/walking pneumonia = Mycoplasma pneumonia
Common cause in alcoholics = Klebsiella pneumoniae = aspirational
Interstitial pneumonia in bird handlers = Chlamydia psittaci
See Pictures
Lung Abscess
Pg 617
- always treat with clindamycin
Pleural Effusion
Pg 615
- Exudative effusions must be drained as soon as possible for risk of infection
Restrictive Lung Diseases
Sarcoidosis
- 10x more common in blacks in US
- non-caseating granuloma = epithelioid histiocytes
- can see asteroid body = giant cell configuration
- peripheral adenopathy
- cutaneous rash = pretrial
- hypercalcemia = due to increased Vit D. (increased 1-alph hydroxylase enzyme)
- BILATERAL HILAR ADENOPATHY
Hypersensitivity Pneumonitis
- noncaseating granulomas in upper portions of lungs
Silicosis
- glass maker, sand blasting
- impairs the phagolysosome formation which causes increased TB risk
- eggshell calcification of hilar lymph nodes
- increased incidence of TB
- nodules coalesce and pull lungs inwards
Berylliosis
- non-caseating granulomas in lungs, hilar lymph nodes (looks like sarcoidosis)
- increased risk for lung cancer
- systemic disease with granulomas in all organs possible
Coal Workers Pneumoconiosis
- with Rheumatoid Arthritis = Caplan syndrome
- build up of carbon inside macrophages = anthracosis
Idiopathic Pulmonary Fibrosis
- TGF-beta from injured pneumocytes induces fibrosis
- must exclude radiation therapy
- lung transplant is only treatment
ANY NONCASEATING GRANULOMA CAN CAUSE HYPERCALCEMIA
ARDS
There is decreased lung compliance due to loss of surfactant and damaged alveoli
- deflating lung is easier than inflating
- lung damage allows neutrophils to get into alveoli and produce cytokines that damage type 1 pneumocytes
- hyaline membranes are formed due to protein exudation
- Type 2 pneumocytes proliferate to fix damaged type 1
Be careful with Ventilator
- high tidal volume ventilation may lead to acute lung injury
Pots Puffy Tumor
- Sinusitis in which there is pus collection under periosteum of frontal bone ==> can cause meningitis
Influenza Virus
- Single Stranded RNA virus
- has nucleocapsid surrounded by matrix
Matrix - Hemagglutinin = required for attachment to cells (decreased infectivity with antibody to this)
- Neuraminidase = required for release of virus from infected cells (antibody correlates with viral shedding and illness severity) => Zanamivir and Oseltamivir
Antigenic drift
- point mutations
- cause epidemics
- occurs in influenza A and B
- reason we get flu shots every year
Antigenic Shift
- major change due to exchange of gene segments
- genetic reassortment
- occurs in A subtypes only
- can cause a pandemic
very bad BODY ACHES
Cyanosis
Patients with normal Hgb manifest cyanosis at higher SaO2 values than patients with anemia
Cilia in Respiratory Tract
Line all the way up to the terminal bronchioles
Obesity Hypoventilation Syndrome
Pickwickian Syndrome
- caused by restricted expansion of the chest wall due to severe obesity. This leads to Hypoventilation with a chronically elevated PCO2 and reduced PO2
Ether
Ether and other organic solvents can inactivate the enveloped viruses which by definition have an outer lipid bilateral coat acquired from the host cell plasma or nuclear membranes
- Non enveloped viruses are resistant to ether
Beta Blocker Overdose
Treated by glucagon
Diastolic heart Failure
- the ejection fraction is normal and left ventricular end diastolic volume is normal
- the left ventricular end diastolic pressure is increased
- due to a stiffened left ventricle
- increased compliance
Systolic Heart Failure
- progressive chamber dilation with increased LV volume and elevated LVEDP
- reduced ejection fraction occurs
- there is a decrease in contractility
- decreased compliance
Coin Lesion
- 1st check previous X-Ray
- 2nd = biopsy lesion
Benign lesions
- GRANULOMA
- bronchial hamartoma = often calcified = has lung tissue plus cartilage
Lung Cancer
Likes to metastasize to the adrenal glands
Pleural involvement occurs with adenocarcinoma
Inhaled Corticosterids
- fluticasone and budesonide
- inhibit the synthesis of virtually all cytokines
- inactivate NF-Kappabeta the transcription factor that induces production of TNF-alpha (inflammatory agent)
- 1st line therapy in chronic asthma in order to be able to reduce inflammation
