Titrating to the optimal pressure. Is transcutaneous electromyography of the diaphragm a good measurement to determine the optimal respiratory support, during continuous positive airway pressure (CPAP), in pre-term born neonates.

At the NICU of the Erasmus MC CPAP is extensively used in the respiratory
support for preterm born neonates. The level of CPAP is set in accordance with
clinical parameters, such as hart frequency, saturation and signs of
respiratory disstress. A reliable clinical parameter, which is representative
for the work of breathing (WOB) is missing. Transcutaneous electromyography of
the diaphragm is a novel technique that could help us in determining the work
of breathing and optimal support level. It measures the electrical activity of
the diaphragm ( in microVolt) and could give an indication of the increase or
decline in work of breathing. The higher the electrical activity the greater
the WOB. This technique is already been used in adult and children. It is
applicable in pre-term neonates. Valid data of its clinical usefulness are
missing.

Primary question:
Are dEMG measurements a clinical marker to assess the WOB in preterm born
neonates?

Three electrodes will be placed in a specific order on the thorax of the
patient. Measurements are done with an EMG monitor ( the Polybench medical
research terminal model A). At the start of actual intervention the patient is
placed I a comfortable position and all medical and nursing interventions are
postponed during the protocol. A stepwise increment and decrease of CPAP, at
intervals of 10 minutes will be made. The adjustment will be 2 cm h20 for each
step, starting at 4 cmH20 with a maximum of 8 cm H20. Measurements will take
place at 5 and 10 minutes, during a "stable" period. A number of stop criteria
are established: discomfort in accordance with the Comfort Neo score, an
increase of oxygen need of more than 15% from baseline,desaturation below the
minimal threshold of 85% for more than two periods, bradycardia below 100/ min
for more than 2 episodes, persistent clinical deterioration as perceived by the
attending neonatologist.

a stepwise in- and decrement of level of CPAP, between 4-8 cm H20, in blocks of
10 minutes.

At the start of the study three extra electrodes are placed on the chest and
abdomen of the patient. These electrodes have a dermatologic safe adhesive,
which is easily removed. To prevent respiratory failure due to hypo or hyper
inflation the stop criteria and clinical condition are leading. If these limits
are overridden, the study will be stopped.