Associate Professor Berger’s work is directed at the respiratory system with a particular focus on control of breathing. The intention of all his research is to develop a rigorous mathematical understanding of how the system operates, and to use this knowledge to create new therapies and devices that effectively treat the respiratory disorders that bedevil humans right across the age spectrum, from the preterm newborn with recurrent apnea and profound arterial oxygen desaturation, to the adult with heart failure and repetitive central sleep apneas lasting half a minute or more.
A/Prof Berger’s publications have provided a number of insights into developmental and disease-related changes in the complex control system for breathing:
- Acceleration of chemoreceptor transduction underlies the observation that periodic breathing, recurrent apnea, and arterial oxygen desaturation occur in infants, with the peak incidence occurring at three months of age when the incidence of SIDS is highest.
- Enhancement of chemoreceptor sensitivity or gain, both spontaneously as in early postnatal life and as a result of heart failure, or through pharmacological means, promotes wild fluctuations in breathing that include apnea.
- Dynamic changes to arterial, venous and alveolar oxygen stores during isolated and repetitive apneas explain the rapidity with which arterial oxygen levels can fall in preterm infants, rendering them prone to dangerously low levels of tissue oxygenation particularly during sleep.
- New medical devices have to date emerged from my laboratory’s work, one a monitor of lung gas volume, the other a monitor of upper airway patency in patients, provide practical means for monitoring and providing treatment to patients with sleep apnea: commercial development of these devices is ongoing.
Joosten SA, O’Donoghue FJ, Rochford PD, Barnes M, Hamza K, Churchward T, Berger PJ, Hamilton GS. (2014) Night-to-Night Repeatability of Supine-related Obstructive Sleep Apnea. Ann Am Thorac Soc; 11(5):761-9.
Nold MF, Mangan NE, Rudloff I, Cho SX, Shariatian N, Samarasinghe TD, Skuza EM, Pedersen J, Veldman A, Berger PJ, Nold-Petry CA. (2013) Interleukin-1 receptor antagonist prevents murine bronchopulmonary dysplasia induced by perinatal inflammation and hyperoxia. PNAS; 110: 14384-14389.
Edwards BA, SA Sands and PJ Berger. (2012) Postnatal maturation of breathing stability and loop gain: The role of carotid chemoreceptor development. Resp Physiol Neurobiol; 185: 144–155.
Sands SA, Edwards BA, Kee K, Turton A, Skuza EM, Roebuck T, O’Driscoll DM, Hamilton GS, Naughton MT, Berger PJ. (2011) Loop gain as a means to predict a positive airway pressure suppression of Cheyne-Stokes respiration in patients with heart failure. Am J Respir Crit Care Med; 184: 1067-1075.
Nemati S, Edwards BA, Sands SA, Berger PJ, Wellman A, Verghese GC, Malhotra A, Butler JP. (2011) Model-based characterization of ventilatory stability using spontaneous breathing. J Appl Physiol; 111(1):55-67.
Stockx EM, Camilleri P, Skuza EM, Churchward T, Howes JM, Ho M, McDonald T, Freezer N, Hamilton G, Wilkinson MH, Berger PJ.(2010) New acoustic method for detecting upper airway obstruction in patients with sleep apnea. Respirology; 15: 326-335.
Sands SA, Kelly VJ, Edwards BA, Davidson MR, Wilkinson MH, Berger PJ. (2010) A dynamic model for assessing the impact of diffusing capacity on arterial oxygenation during apnea. Respir Physiol Neurobiol; 171: 193-200.
Sands SA, Edwards BA, Kelly VJ, Skuza EM, Davidson MR, Wilkinson MH, Berger PJ. (2010) Mechanism underlying accelerated arterial oxygen desaturation during recurrent apnea. Am J Respir Crit Care Med; 182: 961-969.
Sands SA, Edwards BA, Kelly VJ, Davidson MR, Wilkinson MH, Berger PJ. (2009) A model analysis of arterial oxygen desaturation during apnea in preterm infants. PLoS Comput Biol; 5: e1000588.
Edwards BA, Sands SA, Feeney C, Skuza EM, Brodecky V, Wilkinson MH, Berger PJ. (2009) Continuous positive airway pressure reduces loop gain and resolves periodic central apneas in the lamb. Respir Physiol Neurobiol; 168: 239-249.
Edwards BA, SA Sands, EM Skuza, EM Stockx, V Brodecky, MH Wilkinson and PJ Berger (2008). Increased peripheral chemosensitivity via dopaminergic manipulation promotes respiratory instability in lambs. Resp Physiol Neurobiol; 164: 419-428.
Stockx EM, CR Anderson, SM Murphy, IRC Cooke and PJ Berger (2007). The development of descending projections from the brainstem to the spinal cord in the fetal sheep. BMC Neuroscience; 8:40
Wilkinson MH, EM Skuza, GC Rennie, SA Sands, SR Yiallourou, RSC Horne and PJ Berger (2007). Postnatal development of periodic breathing cycle duration in term and preterm infants. Ped Res; 62: 331-336.
Pfister RE, C A Ramsden, HL Neil, MA. Kyriakides and PJ Berger (2001). Volume and secretion rate of lung liquid in the final days of gestation and labour in the fetal sheep. J Physiol; 535: 889-899.
Berger PJ, EM Skuza, V Brodecky, SM Cranage, TM Adamson and MH Wilkinson (2000). Unusual respiratory response to oxygen in an infant with repetitive cyanotic episodes. Am J Resp Crit Care Med; 161: 2107-2111.