NLHEP Quality Checks
In order for the interpretation to be displayed a manoeuvre must pass
a set of enhanced quality checks. After the patient has performed a
poor quality manoeuvre, one of the three following messages will
appear:
Message
Don't
Back-extrapolated volume
hesitate
(BEV) greater than 150 ml
Blast out
Time until peak flow
faster
(PEFT) greater than 120
msec
Blow out
Expiration time less than 6
longer
seconds or volume
accumulation has not
dropped below 100 ml per
0.5 seconds
Once an acceptable manoeuvre has been performed, the following
consistency checks will also be applied to subsequent manoeuvres
Blast out
Peak flow not
harder
reproducible. The best
previous manoeuvres do
not match within 1.0 L/sec
indicating that the patient
is giving an inconsistent
effort.
Deeper
FEV1 or FEV6 not
breath
reproducible. Difference
with respect to best test
greater than 150 ml
Criteria
68
Recommended action
The patient should blast
out the air more quickly
and evenly and without
hesitation at the
beginning of the
manoeuvre
The patient must exhale
more explosively at the
beginning of the
manoeuvre
The patient stopped
exhaling too early. The
patient must exhale until
their lungs are completely
empty.
The patient must give
their maximum effort for
each manoeuvre
The patient must inhale
until
their
completely
full
each manoeuvre
lungs
are
before