To Stent or Not to Stent: That’s Just the First Question
WABIP Newsletter
S E P T E M B E R 2 0 2 4 V O L U M E 1 2 , I S S U E 3
EXECUTIVE BOARD
Stefano Gasparini, MD
Italy, Chair
Pyng Lee, MD, PhD
Singapore, Vice-Chair
Hideo Saka, MD
Japan , Immediate Past-
Chair
Silvia Quadrelli, MD
Membership Commiee
Chair
Jean-Michel Vergnon, MD
Educaon Commiee
Chair
Ali Musani, MD
Finance Commiee Chair
Naofumi Shinagawa, MD
Japan,
Secretary General
Menaldi Rasmin, MD, PhD
Indonesia , President
WCBIP 2024
Rajesh Thomas, MD, PhD
Melbourne , President
WCBIP 2026
STAFF
Michael Mendoza
General Manager
Judy McConnell
Administrator
Kazuhiro Yasufuku
Newsleer Editor-in-chief
P A G E 2
Airway stenng has long been a signicant part of
the intervenonal bronchoscopist’s repertoire when
it comes to endoscopic management of malignant
central airway obstrucon (MCAO). However, there
is marked variability in how and when this interven-
on is oered.
1,2
Even the generally held noon that
stenng should be reserved for cases involving ex-
trinsic airway compression (whether exclusively or
combined with endoluminal disease) is not univer-
sally adhered to.
3
Perhaps unsurprisingly, no guide-
lines had previously been published to help clinicians
on this subject.
That changed with the recent publicaon of the
World Associaon for Bronchology and Intervenon-
al Pulmonology (WABIP) guidelines on airway
stenng for MCAO.
4
A group of 17 experts across 11
countries spanning four connents addressed six
important quesons with mutual consensus (using
the modied Delphi technique) based largely on a
systemac review of published literature.
Only one of the six recommendaons was graded as
“strong” - namely that airway stenng be considered
in paents with MCAO receiving mechanical venla-
on - although the supporng evidence based on
retrospecve observaonal data was judged to be of
low quality (grade 1C recommendaon).
5
Weak rec-
ommendaons - made based on somemes con-
icng evidence that was deemed low-to-moderate
quality - were also made to consider airway stenng
as a means to improve quality of life, performance
status, and survival. Another weak recommendaon
(grade 2C) was to perform surveillance bron-
choscopies to detect stent-related complicaons in
asymptomac paents, with the rst surveillance bronchos-
copy scheduled 4-6 weeks aer stenng. Across all clinical
scenarios, the expert panel determined that no conclusive
evidence supported the selecon of one over the other
commercially available stent type (silicone versus metallic).
Finally, in the absence of any evidence for or against it, the
group’s consensus was in favor of undertaking pulmonary
hygiene measures such as saline nebulizaon to reduce the
risk of stent-related complicaons (nine experts strongly
agreed, seven agreed, and one neither agreed nor disa-
greed).
So, how does the bronchoscopist incorporate these guide-
lines going forward? The very rst queson facing every
bronchoscopist is whether to stent or not. Hamstrung by
limited scienc evidence, these guidelines parally help
answer this queson. However, the role of ascertaining the
degree of airway obstrucon in making treatment decisions
remains unclear. For example, if there is no respiratory dis-
tress or other signs and symptoms aributable to MCAO,
what if any is the minimum degree of extrinsic airway com-
pression that warrants airway stenng? Does that vary with
the locaon of MCAO (e.g., trachea versus a mainstem
bronchus versus bronchus intermedius)? What is an appro-
priate metric for quanfying airway obstrucon? Is it airway
diameter, airway cross-seconal area, length of airway
aected, and/or drop in airway pressure across the aected
segment? What is a valid means of measuring airway size?
Is it the bronchoscopist’s esmate based on endoscopic
images, automated measurements on segmented endo-
scopic images, pre-operave or intraoperave computed
tomographic imaging (stac or dynamic), or bronchoscopic
tools such as a calibrated airway balloon? Of course, lest we
forget, to stent or not to stent is merely the rst queson
out of many. The remaining quesons - including but not
Ali I. Musani MD, FCCP
Professor of Medicine and
Surgery
Director, Complex Airway Pillar
of the Center for Lung and
Breathing
Director, Intervenonal
Pulmonology Program
Director, Global Health
Pathway, Internal Medicine
Residency Program
Division of Pulmonary Sciences
& Crical Care Medicine
Majid Shaq MD, MPH
Medical Director, Bedside
Procedure Service
Medical Director, Intervenonal
Pulmonology
Div. of Pulmonary & Crical Care
Medicine, BWH
Assistant Professor of Medicine,
Harvard Medical School