How to ventilate preterm infants with lung compliance close to circuit compliance: real-time simulations on an infant hybrid respiratory simulator

• Published in: Medical & biological engineering & computing Vol. 58; no. 2; pp. 357 - 372
• Main Authors: Stankiewicz, Barbara, Pałko, Krzysztof J., Darowski, Marek, Kozarski, Maciej
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.02.2020; Springer Nature B.V
• Subjects: Biomedical and Life Sciences; Biomedical Engineering and Bioengineering; Biomedicine; Circuits; Computer Applications; Computer simulation; Human Physiology; Hypercapnia; Imaging; Infants; Lungs; Mechanical ventilation; Newborn babies; Original; Original Article; Premature babies; Pressure; Radiology; Respiration; Respiratory rate; Respiratory system; Respiratory therapy; Strategy; Ventilation; Ventilators; Infant; Conventional mechanical ventilation; Circuit compliance; Permissive hypercapnia
• ISSN: 0140-0118; 1741-0444
• DOI: 10.1007/s11517-019-02089-5

Circuit compliance close to lung compliance can create serious problems in effective and safe mechanical ventilation of preterm infants. We considered what ventilation technique is the most beneficial in this case. A hybrid (numerical–physical) simulator of infant respiratory system mechanics, the Bennett Ventilator and NICO apparatus were used to simulate pressure-controlled ventilation (PC) and volume-controlled ventilation with constant flow (VCV CF ) and descending flow (VCV DF ), under permissive hypercapnia (PHC) (6 ml kg −1 ) and normocapnia (SV) (8 ml kg −1 ) conditions. Respiratory rate (RR) was 36 or 48 min −1 and PEEP was 0.3 or 0.6 kPa. Peak inspiratory pressure (PIP), mean airway pressure (MAP), and work of breathing by the ventilator (WOB) were lower ( P < 0.01, 1 − β = 0.9) using the PHC strategy compared to the SV strategy. The WOB increased ( P < 0.01; 1 − β = 0.9) when the RR increased. The PC, VCV CF , and VCV DF modes did not differ in minute ventilation produced by the ventilator (MV V ), but the PC mode delivered the highest minute ventilation to the patient (MV T ) ( P < 0.01; 1 − β = 0.9) at the same PIP, MAP, and WOB. The most beneficial ventilation technique appeared to be PC ventilation with the PHC strategy, with lower RR (36 min −1 ). Graphical abstract The effectiveness of an infant ventilation depending on circuit compliance to lung compliance ratio (C v C L -1 ) and inspiration time (T i ). V V , V T , tidal volume set on the ventilator and delivered to patient, respectively