Rhinomanometer NR6
NR6 User
’s
Manual V 16 14/02/2020 P11 of 34
Connect the free end of the anterior tube to the black ringed pressure tube from the NR6, using
the anterior connector.
POSTERIOR TEST
(detailed on P16)
In the posterior test, a length of posterior tubing is connected onto the black nozzle inside the
mask
–
cut just long enough to sit on the tongue - and the lips closed round the tube. Provided
the soft palate is relaxed, the pressure measured by this mouth tube will be the same as the
pressure driving airflow through the nose. This pressure signal is taken to the NR6 by means of
the tube with the black ring marker on it, which is connected to the black nozzle on the outside
of the mask. The reference pressure tube (blue) is also connected to the outside of the mask.
Patient co-operation is required to use this technique, in which a measure of total nasal
resistance is obtained from one test.
PRINCIPAL POINTS TO NOTE
1) Prepare the patient by having them wait in relaxed quiet conditions for 15 to 20 minutes
prior to measurements being taken, and decongest them
2) Check for leakage of the pressure tube and for good mask fit
3) Ask the patient to breathe in a quiet relaxed way - avoid excited, rapid manoeuvres
Posterior and Anterior tests can be performed using a fixed reference level (selectable from 75
to 300 Pa or cc/sec) or, alternatively, under the Broms technique with a radius of 200 units. In
either case, resistance is calculated when the trace crosses the fix line or arc of the circle.
The recommended reference points are as follows:
Standard posterior
75 Pa
Standard anterior
150 Pa
Broms
200 units
Resistance values averaged over at least 4 breaths is recommended and offered by default.
In addition to resistance values, Rohrer coefficients are also calculated for K1 and K2:
K0 should be zero as the curve goes through the origin
K1 represents the laminar flow part of the curve
K2 represents the turbulent part of the curve
