Page 12 - Physiological based CPAP for preterm infants at birth Tessa Martherus

Preface
It is 9.20 AM and the handover for neonatal clinical staff, as well as a joint Inter-Departmental meeting, had just finished when the neonatal resident received an incoming call. Overnight, a woman was admitted into hospital at 26 weeks gestation with preterm rupture of membranes and contractions. Labour continued despite tocolytic treatment and the cervix was 8 centimetres dilated, making it likely that her baby would be born that day. With twenty-six weeks into the pregnancy and an estimated fetal weight of 920 grams, her child was going to be born too soon and would need medical assistance to transition from a fetus into a newborn infant.
The neonatal resident called her supervising neonatologist and asked a nurse for assistance. Next to the delivery suite where the woman was to give birth, the neonatologist, resident and nurse prepared the resuscitation table. They switched on the radiant heater above the resuscitation table to prewarm the table and turned on the pulse oximetry monitor and oxygen analyser to measure heart rate, oxygen saturation and the amount of supplemental oxygen that is given when providing respiratory support. Furthermore, they calibrated the resuscitation monitor, which displayed and recorded all physiological parameters, including respiratory function. The resident set the T-Piece resuscitator to deliver positive end- expiratory pressures of 5 cmH2O and peak inspiratory pressures of 20 cmH2O, using a flow of 12 L/min. The air/oxygen blender was set on a concentration of 30% oxygen and a syringe full of caffeine was prepared in case respiratory effort was insufficient.
Only minutes later, the neonatologist entered the resuscitation room and gently placed the newborn infant on the table. Her breathing was spontaneous, but irregular. The neonatologist positioned the infant in a plastic wrap and supported her breathing with 5 cmH2O continuous positive airway pressure (CPAP) and an inspired oxygen content of 30% by placing a mask over her nose and mouth. Despite intermittent tactile stimulation, her irregular breathing rapidly diminished, eventually resulting in apnea. The neonatologist started artificial ventilation, starting with 5 inflations, each with a duration of 3 seconds. The pulse oximetry device displayed a reliable plethysmograph signal, a heart rate of 65 beats per minute and an oxygen saturation of 54%. Therefore, a second group of inflations were given while increasing the peak inspiratory pressure to 25 cmH2O, which increased heart rate to 120 beats per minute. As there was still no sign of breathing and the oxygen saturation had not improved, they continued with positive pressure ventilation and the nurse increased the inspired oxygen concentration to 50%. After a minute of ventilation, they observed spontaneous breathing on the respiratory function monitor and stopped ventilation to evaluate her breathing efforts. While the infant breathed spontaneously, she made grunting noises, indicating that she was struggling to preserve lung volume. Her breathing remained irregular and was merely enough to maintain peripheral oxygen saturations at 82%, while still receiving an inspired oxygen content of 50%. To further support her breathing effort, the neonatologist increased the CPAP pressure to 8 cmH2O, and to stimulate breathing, they administered caffeine via a butterfly needle inserted into the umbilical vein. Meanwhile, the obstetrician entered accompanied with the father and the team first congratulates the father before explaining to him how she
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