Resp 4 Flashcards
Hypersensitivity of rep center to CO2;
Period of waxing & waning of VT separated by periods of apnea
Cheyne-Stokes Respiration
Causes of Cheyne-Stokes Respiration
Drug overdose, CHF, hypoxia
Obesity-hypoventilation syndrome
Pickwickian Syndrome
Clinical signs of Pickwickian Syndrome
Partial airway obs causes snoring; Hypoxia; Cyanosis; Rarely hypercapnia; Polycythemia; Poor sleep at night/day time sleepiness
“Reversible” increased resistance to airflow d/t airway narrowing
Ashtma
What would a CXR show with asthma?
Hyperinflation, flattening of diaphragm, mucus plugging, atelectasis
What is 40@40?
A respiratory emergency seen with asthma where CO2 is 40 (normal or high) and PO2 is 40. (Means nothing is going in or out)
Diagnostic findings with asthma
Peak flow exp rate decreased;
FVC, FEV1, & FEV1/FVC decreased;
Increased RV;
Normal diffusion capacity (DLCO)
Management of acute asthma attack:
- B2 agonist + steroid + ipratropium;
2. Systemic steroid (IV);
Management of chronic asthma disease
- Inhaled steroid as maintenance + inhaled B2 steroid for symptomatic control;
- Add ipratropium;
- Aminophylline;
- Short course of oral steroid
How does Terbutaline affect bronchial smooth muscles?
B2 stimulant acts on B2 receptors > Gs protein > adenyl cyclase > increase cAMP > activation of protein kinases > bronchodilaiton
How does Aminophylline affect bronchial smooth muscle?
PDE inhibitor > increase cAMP > bronchodilation
Nitric Oxide (NO)
Converts GDP to cGMP > bronchodilation;
No cell receptor/crosses cell membrane
Destruction of alveolar walls and abnormal enlargement of air spaces distal to terminal bronchiole
Chronic pulmonary emphysema
Prevents mast cell degranulation and exercise induced asthma
Cromolyn
How does emphysema lead to RHF “Cor pulmonale”?
The hypoxia causes vasoconstriction which leads to pulm HTN
Diagnostic findings of COPD
Airflow obstruction of PFTs; Decreased FEV1 & FEV1/FVC; Prolonged FR time > 6 sec; Decreased DLCO; Increased RV & TLC
Tx for COPD
Smoking cessation, abx, bronchodilators, steroid, supplemental O2 with PO2, 55mmHg
Restrictive dz w/ decreased lung compliance in which inspiration is impaired
Pulmonary Fibrosis
Pulm. Fibrosis is characterized by a ____ in all lung volumes. The FEV1/FVC is ______.
Decrease; increased or normal
Rales, cough, infiltration, and fatal fibrosis
Bleomycin lung
Alveoli are filled w/ fluid & cellular debris (consolidation);
Impaired gas exchange;
Low V/Q ratio;
Hypoxia & hypercapnia
Pneumonia
The development of active tubercles throughout the body
Miliary tuberculosis
Positive Mantoux test shows:
Recent immunization; previous TB test, past exposure to M. Tuberculosis; need further tests
Abx used to tx TB
INH, pyrazinamide, rifampin
PHTN (mmHg)
> 25 mmHg or > 35 mmHg during exercise
Primary pulmonary HTN
D/t an inactivating mutation in the BMPR2 gene (normally fxns to inhibit vascular smooth muscle proliferation)
Pathological consequences from PE
Increased PVR;
Increased PAP;
Increased RV afterload
Risk factors for PE
FAT BAT: fat, air, thrombus, bacteria, amniotic fluid, tumor
Clinical features of PE
Sudden onset of dyspnea, pleuritic CP, tachypnea >resp alkalosis, RV overload (loud P2, RV heave)
Homan’s sign
Tender calf muscle with dorsiflexion of foot. Sign of DVT
Most sensitive & specific test for PE. Look for filling defect
CT arteriography
PTT w/ Heparin
1.5-2.5 x normal + 30 sec
PT with warfarin
12 sec
Indications for PEEP
PO2 < 60 mmHg;
Widespread alveolar collapse/atelectasis;
ARDS;
Pulm edema
Dose of PEEP
5-10 cmH2O
Complications of PEEP
Decreased CO d/t interference w/ venous return;
Barotrauma (pneumo);
Fluid retention d/t obstruction of lymph flow & capillary damage;
Redistribution of pulm blood flow > decrease V/Q > Decrease PO2
CPAP level
< 14- 15 cmH2O (lower than LES pressure)
Produced by dynamic compression of the airways during a forced expiration, occupies most of expiratory limb of the loop
Effort independent flow
F/V loop shows lung volumes are smaller
Restrictive disease
F/V loop shows expiratory limb is prolonged & lung volumes are greater
Obstructive disease
F/V loop shows Inspiration is impaired
Extrathoracic obstruction
F/V loop shows Expiration is impaired
Intrathoracic obstruction
F/V loop shows both inspiration & expiration are impaired
Tracheal obstruction
During a forced expiration, airways begin to close. The volume that can subsequently exhaled is?
Closing volume
Closing capacity =?
Closing volume + residual volume
Closing volume ______ with age, COPD, airway secretion, anesthesia
Increases
Blood flow & ventilation to dependent lung are ____ than nondependent lung in the unanesthetized pt
Greater
In the anesthetized/paralyzed pt the ________ lung is well ventilated but poorly perfused (dead spacing). The _____ lung is poorly ventilated and well perfused (shunting).
Nondependent; dependent
Chronic necrotizing infxn of bronchi leading to dilatation and destruction of airways, purulent sputum, recurrent infxns, & hemoptysis
Bronchiectasis
Sx of bronchiectasis
Chronic purluent cough w/ large amt of sputum, clubbing, & air fluid levels on CXR
Non-cardiogenic pulm edema d/t damage to alveolar-capillary membrane (stiff lungs);
Severe Hypoxemia (PO2 < 60, FIO2 > 60, large A-a gradient);
Bilateral pulm infiltrates
Adult respiratory distress syndrome (ARDS)
Loud ___ suggest pulm HTN
P2
