Bleomycin induced pulmonary toxicity

Explain high mortality rate (50%) of pulmonary toxicity

Can lead to fibrosis (direct injury to lung) which is IRREVERSIBLE

Most frequent presentation of bleomycin induced pulmonary toxicity

Pneumonitis ; can progress to pulmonary fibrosis

MOA of bleomycin on pulmonary toxicity

Reacts with oxygen to create free radical that damages pulmonary endothelial cells (lungs lack the amino hydrolysis, the enzyme that degrades bleomycin)

Explain why bleomycin causes damage specially to the lungs

The lungs lack aminohydrolase, which is the enzyme that inactivates bleomycin

T/F: age > 70 is a risk factor for bleomycin-induced pulmonary toxicity

True

T/F: age < 70 years is a risk factor for bleomycin-induced pulmonary toxicity

False

• but that doesn’t mean that this population won’t get it ! Bleomycin induced pulmonary toxicity is unpredictable

T/F: cumulative dose > 400 units (or > 200 units/m²) is a risk factor for bleomycin-induced pulmonary toxicity

True

T/F: supplemental high fraction of inhaled O2 is a risk factor for bleomycin-induced pulmonary toxicity

True

____ exacerbates bleomycin-induced pulmonary toxicity

Oxygen

Oxygen can cause ____ in patients receiving bleomycin

Respiratory failure

DOC for pulmonary toxicity

corticosteroids (aggressive regimen + IV)

What should you be cautious of using when managing pulmonary toxicity?

Be cautious w/ supplemental oxygen (ie intubation)

• produces more free radicals

• Goal: maintain O2 SAT 89-92%

Prevention strategy

• Closely monitor cumulative dose of bleomycin

• Reduce use in elderly pts