Module 4.3 - Restrictive (Inflammatory) Lung Diseases Flashcards
(38 cards)
Define restrictive lung disease
Restrictive lung diseases are characterized by reduced lung volumes. Unlike obstructive lung diseases which show a normal or increased total lung capacity (TLC), restrictive diseases are associated with a decreased TLC.
What causes restrictive lung disease?
There are many disorders that cause reduction or restriction of lung volumes.
- The first is intrinsic lung diseases or diseases of the lung parenchyma.
- The diseases cause scarring of the lung tissue (interstitial lung disease) or result in filling of air spaces with exudate and debris (pneumonitis)
- The second is extrinsic disorders or extra pulmonary disorders – specifically disorders of the chest wall, pleura and respiratory muscles (neuromuscular disorders).
What is pneumonia?
- Acute febrile inflammatory disorder of the lung(s) associated with cough and exertional dyspnea.
- An infiltrate is seen on CXR, sometimes 24-48 hrs. after symptoms begin.
- Leukocytosis may be present.
Describe the etiology/incidence associated with pneumonia
- Most common of all serious lung conditions, frequent cause of acute care hospitalizations and mortality
- Elderly at risk due to poor immune systems, debilitated state, fragility
- Over treatment with antibiotics of mild URI has contributed to antimicrobial drug resistance, especially S. pneumoniae
- These comorbidities cause a higher mortality in patients with pneumonia: COPD, HF, DM, chronic liver and kidney disease.
- Very young and very old patients are also at high risk for death despite adequate treatment with antibiotics.
What are the typical symptoms associated with pneumonia?
fever, chills, leukocytosis, cough, and sputum production increased fremitus. CXR may show single infiltrate
What are the atypical symptoms associated with pneumonia?
fever may be high, +/- leukocytosis. A left shift may be present, dry cough, HA, sore throat, excessive sweating, chest soreness,
What are the common organisms associated with Community acquired pneumonia (CAP)?
- Most common bacteria – Streptococcus pneumoniae (most common), Haemophilus influenza, Klebsiella pneumoniae, gram negative organisms.
- Atypical pathogens – Chlamydia pneumoniae, Mycoplasma pneumoniae, Mycobacterium tuberculosis.
- Viruses – respiratory syncytial virus, adenovirus, rhinovirus
What is and what are the common organisms associated with Hospital acquired pneumonia (HAP)?
It is a Nosocomial infection that occurs 48 hrs. or more after admission. The most common organisms include:
- Staphylococcus aureus
- Streptococcus pneumoniae
- Haemophilus influenzae
What is and what causes Ventilator acquired pneumonia (VA)?
- Pneumonia that occurs 48-72 hrs. after intubation.
- Most common culprit: Pseudomonas
How would you evaluate a patient with suspected pneumonia?
Conduct a physical exam and look out for – tachycardia, tachypnea, fever, rales or crackles present over the affected lung, mental status changes, or confusion
Obtain a CXR – assess for infiltrates, may repeat if no infiltrate seen initially but pneumonia is still suspected
Check – CBC including white count, blood cultures, gram stain and culture of sputum, ABG and spirometry, procalcitonin levels if available.
How do you treat outpatient pneumonia?
- Treat initially with a macrolide (azithromycin, clarithromycin, Erythromycin) or doxycycline for 5 days
- Therapy should be revised as culture results are reported, if indicated, as initial treatment is empiric.
- Remember to assess patient clinically for ongoing improvement or worsening of symptoms. Use the narrowest spectrum antibiotic. Cover anaerobic organisms incases of known or suspected pneumonia. Not all patients need hospitalization for treatment
What is the criteria for ICU admission for patients with pneumonia?
- Need mechanical ventilation
- Have hypotension (systolic BP ≤ 90 mm Hg) that is unresponsive to volume resuscitation
- Other criteria that mandate consideration of ICU admission include
- Respiratory rate >30/min
- Pao2/fraction of inspired oxygen (Fio2) < 250
- Multilobar pneumonia
- Diastolic BP < 60 mm Hg
- Confusion
- BUN > 19.6 mg/dL
What does the CURB-65 scoring system stand for and what is it used for?
- Confusion
- Uremia (BUN ≥19 mg/dL)
- Respiratory rate > 30 breaths/min
- Systolic BP < 90 mm Hg or diastolic BP ≤ 60 mm Hg
- Age ≥ 65 yr
1 point is given for each risk factor and when added up determines the need for hospitalization.
Describe the point system used in the CURB-65 system.
0 or 1 points: Risk of death is < 3%. Outpatient therapy is usually appropriate.
2 points: Risk of death is 9%. Hospitalization should be considered.
≥ 3 points: Risk of death is 15 to 40%. Hospitalization is indicated, and, particularly with 4 or 5 points, ICU admission should be considered.
What 2 vaccinations are available to prevent pneumonia?
- PCV 13: pneumococcal conjugate vaccine for infants, children and adults older than 19 years at high risk for disease
- PPSV23: pneumococcal polysaccharide vaccine for adults older than 65 years of age and those older than 2 years of age at high risk.
What causes tuberculosis?
- Mycobacterium tuberculosis.
- The lungs are the major site for primary infection and disease. Manifestations include primary TB and reactivation TB.
What are the symptoms associated with tuberculosis?
Many patients are asymptomatic.
Typical symptoms include:
- Fever is generally gradual, begins with low grade, can be as high as 390 C and last for 14-21 days
- Cough
- Productive, purulent sputum that may contain blood
- Weight loss
- Night sweats severe enough that may require changing bed linens
- Dyspnea can occur in the setting of extensive parenchymal involvement, if pleural effusions develop or if a pneumothorax occurs.
What are the physical exam findings found in someone with tuberculosis?
Physical exam findings:
- febrile
- cachexia may be noted (consumption)
- rales over the affected areas
- atypical posttussive rales (heard after a short cough).
- Dullness with decreased fremitus may indicate pleural thickening.
- Distant hollow breath sounds may be heard.
In the absence of treatment:
- patients may present with painful ulcers of the mouth, tongue, larynx or GI tract due to chronic expectoration and swallowing highly infectious secretions. These findings are rare in the setting of treatment. In general, patients in the ambulatory setting will present with milder symptoms than those diagnosed in the hospital.
What lab changes are found in patients with TB (CBC, Chemistries, Cortisol, Sputum)?
- CBC – frequently normal initially, normocytic anemia, leukocytosis may be seen in later disease
- Chemistries – frequently normal initially. Hyponatremia, hypoalbuminemia and hypergammaglobulinemia are late findings.
- Cortisol – level may be low if disseminate disease to the adrenal glands and has destroyed the adrenal cortices
- Sputum – acid-fast smears are often positive. Therapy may have to be started empirically if clinical signs are suggestive of TB but smear is negative. Cultures for M. tuberculosis are usually positive within 6 weeks
What does a skin PPD test for, and when and how do you interpret its results?
intradermal purified protein derivative. This test indicates exposure only, not active disease. TB skin test has been used for years as an aid in diagnosing latent tuberculosis infection (LTBI). Its result is a measurement of a hypersensitivity response.
Findings after 48 hours should be interpreted as:
- Less than 5 mm (indurated area only) is negative
- 5 mm or more is positive in HIV infected patient, recent TB exposure, immunocompromised patient or one with chest x-ray typical for TB
- 10 mm or more is positive in health care workers, HIV negative injection drug users, residents in nursing homes, homeless shelters or recent immigrants.
15 mm or more is positive in any situation/person
How is the Quantiferon Gold Test used for TB testing?
- It is a serum test for diagnosis of TB, either latent or active, used instead of PPD.
- The results are less subjective to reader bias and error and is quickly replacing the traditional testing in some practices although the CDC discourages the use for those patients among populations at low risk.
What and when are chest x-ray changes seen for TB?
Infiltrates can be present in any portion of the lungs but are usually seen in the upper lobes or in the superior segments of the lower lobes. Cavitation is seen.
What are the treatment options for patients who have suspected TB disease, smear positive, or have sputum culture results pending?
A four drug therapy is recommended for these patients:
- Isoniazid 300 mg PO daily – maximum 300 mg daily, with pyridoxine 50 mg PO, to prevent INH induced peripheral neuropathy.
- Rifampin (Rifadin/Rimactane) 600 mg PO daily (or 10 mg/kg daily, maximum 600 mg/dose).
- Ethambutol (Myambutol) 15-25 mg/kg PO each day (maximum 2.5 grams/dose) preceded by screening of color vision. Note: Ethambutol (Myambutol) may cause red/green color blindness as an adverse effect as well as changes in visual activity.
- Pyrazinamide 15-30 mg/kg PO in three divided doses (maximum 2 grams/dose)
Modification of regimen may be necessary if drug susceptibility studies demonstrate resistance to first line drugs. If isolate proves to be fully susceptible to INH and RIF then ethambutol may be dropped. Therapy is continued for 6-9 months. 6 months is generally sufficient for most patients, 9 months is indicated for HIV and other immunocompromised patients.
What are the treatment options for non-adherent patients with TB?
Directly observed treatment may be initiated at 3 times per week, usually after 2 weeks of observed therapy, and is often done in the hospital. May follow one of three regimens:
- INH + rifampin + pyrazinamide + ethambutol daily for 2 months followed by INH + rifampin 2-3 times weekly for an additional 4 months, especially if susceptibility to INH/rifampin is noted
- INH + rifampin + pyrazinamide + ethambutol daily for 2 weeks. followed by the same agents weekly for 6 weeks, then INH + rifampin 2 times weekly for 4 months, if susceptibility to both is noted
- Thrice weekly dosing of INH + rifampin + pyrazinamide + ethambutol for 24 doses (8 weeks) followed by thrice weekly dosing of INH + rifampin for 54 doses (18 weeks)
Patients with advanced HIV (CD4 counts less than 100/ul) should be treated with daily or three times weekly therapy in both the initial and continuous phases of treatment.
