Harrison 21st Update Pulmonology

Diagnostic Procedures in Respiratory Diseases (P: 2140-2147)  

EBUS-TBNA: Endobronchial Ultrasound Guided Transbronchial Needle Aspiration (of the lymph node) has a 90% sensitivity for identifying epithelial cancer and a 70% sensitivity for lymphoma (which is more likely to detect a recurrence of lymphoma than a leukemia from scratch).  The EBUS-TBNA has an 80% increased sensitivity for sarcoidosis when paired with endobronchial biopsy.

ROSE: TBNA Biopsies: Rapid Onsite Cytological Examination  Noble Gas MRI: Hyperpolarized 3He is the agent employed. It is used to evaluate airway ventilation and perfusion.

Further information regarding CT: Pulmonary arterial pressure is directly correlated with the quality of the central pulmonary arterial trunk near its first bifurcation.  The s/o ↑ pulmonary artery pressure is measured at > 3 cms.  There is a correlation between disease severity and the ratio of PA diameter to adj. aorta diameter (PA/A). 

Revised Interpretation of Sweat chloride test

• > = 60 mmol/l is elevated ? Diagnosis of CF
• <30 mmol/L is low.
• 30-59 is intermediate.

Asthma

Modifies the GINA 2021 guidelines slightly.  PD20 (Provocative dose 20): a dosage of methacholine that reduces FEVI by 20%.  Value less than 400 µg: indicates hyperreactivity of the airways. In untreated patients, FeNo >35–40 ppb is suggestive of eosinophilic inflammation.
For patients with severe asthma on moderate to high close ICS, >20–25 ppb indicates noncompliance.

Omalizumab (Anti-IgE)

For patients whose asthma symptoms are not controlled by moderate to high doses of ICS and who have an IgE level of ≥ 30 IU/ml and a positive skin test or RAST to a perennial allergen. Individuals with FeNo > 20 ppb and an Eosinophil Count ≥ 260/l are the best responders. 

Bronchial thermoplasty

Not recommended other than in the setting of a clinical trial

IL5 Drugs

Recommended in patients with symptomatic on moderate to high dose ICS/LABA. With ≥2 exacerbations requiring oral steroid/year-Eosinophil count >= 300/µL. Agents-Anti-IL5-Mepolizumab, Reslizumab. Anti IL5R

-Benralizumab

IL4/1L13 blockers

Dupilumab. Same indications as IL5 drugs but can also be used in patients with eosinophil count <300/μl.

Definition of severe asthma 

Uncontrolled asthma on step 5 medication or asthma requiring step 5 medication for control following co-morbidity evaluation, education, and trigger minimization. 

COPD

The management recommendations in GOLD 2021 are mostly followed by HPIM 21st ed.  Preserved Ratio Impaired Spirometry (PRISm COPD)
Patients in the COPD subgroup with FEV1 ≤ 80% but FEV and/or FVC > 70% .  Emphysema usually strikes these people later in life, and they may advance straight to GOLD stages 3 or 4.

Indications of LTOT (Long Term Oxygen Therapy) in COPD

Individuals having a resting SpO2 of at least 88% or 89%.  With erythrocytosis, right heart failure, pulmonary hypertension, or recently added advice 

Vaccination for COPD pts

• Annual influenza vaccination
• Pneumococcal vaccine
• Pertussis Vaccine (Tdap)
• Recommended in gold guideline 2021

Lung Transplantation

Contraindications to Lung Transplantation
	Absolute Contraindications	Relative Contraindications
Surgical considerations	Anatomic abnormalities not amenable to transplant procedure
Age		>65 years
Functional status	Immobility, inability to participate in physical therapy/rehabilitation	Limited functional status as defined by 6-minute walk distance
Medical comorbidities	Untreatable, irreversible organ dysfunction	Chronic kidney disease
	Active malignancy or malignancy with insufficient remission period
	Active bacterial bloodstream infection	Infection resistant to treatment or of high risk for posttransplant morbidity/mortality (Burkholderia cenocepacia, Mycobacterium abscesses)
	Uncontrolled viral infection (HIV, hepatitis)
Nutritional		BMI <18 or >30-35
Psychosocial	Untreatable, irreversible psychiatric disorder with potential to impact transplant outcome
	Active substance abuse	Limited social supports
	Other circumstances that would complete ability to participate in and comply with posttransplant care	History of noncompliance with medical treatment

Characteristics of the Ideal Lung Donor
Donor age	<55 years
ABO compatibility	Identical
Chest radiography	Clear
PaO2:FiO2	>300 on PEEP 5-cm H2O
Tobacco History	<20 pack-years
Chest Trauma	Absent
Evidence of aspiration	Absent
Prior thoracic surgery	None
Sputum gram stain	Negative
Bronchoscopy Findings	No purulent secretions

Predictors of Survival After Lung Transplantation
	1 Year Survival	≥10 Year Survival
Donor factors	HCV donor
Recipient factors	Age <70 years Diagnosis other than pulmonary fibrosis, pulmonary hypertension, sarcoidosis, A1AT O2 requirement <5LCl >2Outpatient at time of transplant Preserved recipient eGFR Total bilirubin <2	Age 18-35 years
Donor/Recipient Factors	Non female to male transplant Donor/recipient weight ratio >0.7	Higher levels of HLA matching
Operative factors	Avoidance of unplanned conversion to cardiopulmonary bypass Decreased ischemic time	Bilateral lung transplant
Posttransplant factors	Pa07/Fi02>260 at 72h Absent need for postoperative ECMO support	Fewer hospitalizations for rejection
Other factors	Higher center volume	Higher center volume

Also Read: Special Considerations in Diabetes Mellitus

Hope you found this blog helpful for your NEET SS Pulmonology Preparation. For more informative and interesting posts like these, keep reading PrepLadder’s blogs.