Supplemental oxygen therapy in bleomycin-induced pulmonary toxicity

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MJAFI Vol 67 No 2
194 © 2011 AFMS
pulmonary function test revealed moderate restrictive defect
with impaired gas exchange, and the repeat pulmonary func-
tion test was normal. It has not been mentioned if DLCO was
performed and how significantly it improved after resolution of
lung lesions. The finding of improved DLCO may have a posi-
tive bearing if the patient subsequently requires supplemental
oxygen therapy for any reason.
REFERENCES
1. Debnath J, Singh HP, George RA, et al. Reversible Bleomycin toxicity.
MJAFI 2010;66:290–291.
2. Goldiner P, Carlon GC, Cvitkovic E, et al. Factors influencing postop-
erative morbidity and mortality in patients treated with bleomycin.
BMJ 1978;1:1664–1669.
3. Kindwall EP. Contraindications and side effects to hyperbaric oxygen
therapy. In: Hyperbaric Medicine Practice, 2nd ed., Kindwall EP, Whelan
HT, eds. Flagstaff AZ: Best Publishing Company, 1999:83–98.
4. Comis RL. Detecting bleomycin pulmonary toxicity: a continued
conundrum. J Clin Oncol 1990;8:765–767.
Contributed by
Surg Lt Cdr Rohit Verma
PMO & Graded Specialist (Marine Medicine),
INS Nireekshak, Kochi – 682004.
Supplemental oxygen therapy in bleomycin-induced
pulmonary toxicity
MJAFI 2011;67:194–195
Dear Editor,
I read with interest the case report “Reversible Bleomycin
Toxicity”.1 The authors have mentioned high-dose oxygen ex-
posure as one of the risk factors for pulmonary toxicity. This is
an important aspect of Bleomycin-induced pulmonary toxicity,
as supplemental oxygen therapy is considered to be a synergis-
tic toxin with Bleomycin, particularly in the setting of general
anaesthesia and hyperbaric oxygen therapy (HBOT). The dos-
age of oxygen which can result in toxicity has not been quanti-
fied. Even a modest increase in fraction of inspired oxygen
(FiO2) to 0.32 or 0.45, intra-operatively, has reportedly resulted
in lung toxicity and death.2 Further, the duration of this rela-
tionship is not well characterised. An exposure to Bleomycin in
the past six months is considered by some to be a significant
risk factor;2 however for delivery of HBOT, even a remote his-
tory of Bleomycin therapy is an absolute contraindication.3
In patients with history of exposure to Bleomycin, requiring
oxygen administration, inspired oxygen concentration is rec-
ommended to be kept at the lowest level, typically at FiO2 of
0.22–0.25, that provides adequate tissue oxygenation. A single
breath, carbon monoxide diffusion capacity (DLCO) is consid-
ered to be the most predictive of potential pulmonary toxicity
where HBOT is being considered.4
The authors in their case report have not described if the
patient received any supplemental oxygen therapy after the
administration of Bleomycin. Also, they report that the initial
REPLY
At the outset, on behalf of all the authors, I thank the reader for
having shown keen interest in the article entitled “Reversible
Bleomycin Toxicity” published in the July issue of MJAFI.1 The
reader has brought out clinically relevant and important issues
pertaining to exacerbation/precipitation of bleomycin-induced
pulmonary toxicity caused by supplemental oxygen adminis-
tration particularly in the context of general anaesthesia. As
mentioned in our article, exposure to high-dose oxygen is one
of the several important risk factors known for development of
bleomycin pulmonary toxicity. We did not go into the details
of the risk factors of bleomycin toxicity as our article focused
mainly on the unusual HRCT features of bleomycin toxicity and
imaging (HRCT) demonstration of reversibility of the lesions.
I agree with the comments of the reader concerned with regard
to the potentially serious synergistic effects of supplemental
oxygen therapy in a patient with prior exposure to bleomycin.
Exposure to bleomycin appears to sensitise the lungs and poten-
tially fatal acute lung damage can occur at an inspired oxygen
concentration which is otherwise considered normal for a healthy
individual. However, this issue is debatable.2,3 Nevertheless, it
may be clinically relevant as many of the patients who receive
bleomycin therapy for a variety of disorders are relatively young
and may subsequently undergo surgery where general anaes-
thesia would be considered. Awareness and knowledge of these
risk factors would certainly prove invaluable in preventing/
avoiding perioperative complications in a patient with prior ex-
posure to bleomycin. At this point, I would like to mention that
the issue of perioperative reduction of oxygen in patients with
prior exposure to bleomycin is also debatable.4,5
There are conflicting reports regarding the role of pulmonary
function tests and carbon monoxide diffusing capacity (DLCO)
as an indicator of bleomycin-induced pulmonary toxicity.6,7
However, the general consensus is that DLCO has an important
role in this regard. As enquired by the reader, I would like to
inform here that our patient did not receive any supplemental
oxygen therapy after the administration of bleomycin. At the