Volume Guarantee High-Frequency Oscillatory Ventilation in Preterm Infants With RDS: Tidal Volume and DCO2 Levels for Optimal Ventilation Using Open-Lung Strategies

Abstract

High frequency oscillatory ventilation with volume-guarantee (HFOV-VG) is a promising lung protective ventilator mode for the treatment of respiratory failure in newborns. However, indicators of optimal ventilation during HFOV-VG mode are not identified yet. In this study, we aimed to evaluate optimal high-frequency tidal volume (VThf) and the dissociation coefficient of CO 2 (DCO 2 ) levels to achieve normocapnia during HFOV-VG after lung recruitment in very low birthweight infants with respiratory distress syndrome (RDS). Preterm babies under the 32nd postmenstrual week with severe RDS that received HFOV-VG using open-lung strategy between January 2014 and January 2019 were retrospectively evaluated. All included patients were treated with the Dräger Babylog VN500 ventilator in the HFOV-VG mode. In total, 53 infants with a mean gestational age of 26.8 ± 2.3 weeks were evaluated. HFOV mean optimal airway pressure (MAPhf) level after lung recruitment was found to be 10.2 ± 1.7 mbar. Overall, the mean applied VThf per kg was 1.64 ± 0.25 mL/kg in the study sample. To provide normocapnia, the mean VThf was 1.61 ± 0.25 mL/kg and the mean DCO 2 corr was 29.84 ± 7.88 [mL/kg] 2 /s. No significant correlation was found between pCO 2 levels with VThf (per kg) or DCO 2 corr levels. VThf levels to maintain normocarbia were significantly lower with 12 Hz frequency compared to 10 Hz frequency (1.50 ± 0.24 vs. 1.65 ± 0.25 mL/ kg, p < 0.001, respectively). A weak but significant positive correlation was found between mean airway pressure (MAPhf) and VThf levels. To our knowledge, this is the largest study to evaluate the optimal HFOV-VG settings in premature infants with RDS, using the open-lung strategy. According to the results, a specific set of numbers could not be recommended to achieve normocarbia. Following the trend of each patient and small adjustments according to the closely monitored pCO 2 levels seems logical.

Target volume‐guarantee in high‐frequency oscillatory ventilation for preterm respiratory distress syndrome: Low volumes and high frequencies lead to adequate ventilation

“…Infants in our sample also had a lower birth weight (728 vs. 882 g and 1100 g) and gestational age than in previous studies (25 vs. 27 and 28 weeks 12,13 ). Compared to those conventionally ventilated, we found that HFOV ventilated newborns also had a lower gestational age and birth weight.…”

“…The chart includes all patients ventilated with HFOV during the first 72 h of life. HFOV, high-frequency oscillatory ventilation; w, weeks T A B L E 1 Epidemiological characteristics of the 116 patients included in the study and subgroup characteristics for different frequency groups median volume of 1.93 ml/kg, and Tuzun et al 13 published data from 53 neonates with frequencies of 10 and 12 Hz and a median volume of 1.65 and 1.50 ml/kg, respectively. Unlike these authors, we analyzed data limited to infants with adequate ventilation, and we limited our sample to preterm newborns HFOV-ventilated before 72 h of life, since ventilation could change with lung inflammation and development during the first days of life.…”

Application of high‐frequency oscillation ventilation combined with volume guarantee in infants with acute hypoxic respiratory failure after congenital heart surgery

“…18 At present, the initial value of VThf commonly applied in clinical practice is generally 1.5-2.0 ml/kg, while the target VThf range used in our study was 2-2.5 ml/kg, with an initial setting of 2 ml/kg. 7,9,19 This is because infants with congenital heart disease often have pulmonary edema and atelectasis after surgery, so they need a higher volume support to maintain normocapnia. Further research is needed to investigate whether these VThf target values change with age, body weight, or underlying disease.…”

Evidence for the Management of Bronchopulmonary Dysplasia in Very Preterm Infants

“…Software algorithms adapt the applied pressure (to a set maximum peak pressure) to the exhaled tidal volumes of the last couple of inflations in order to achieve an expiratory tidal volume matching the set volume as closely as possible [ 87 ]. Targeted tidal volumes are usually set to 4–6 mL/kg in conventional ventilation [ 87 ] and 1 to 2 mL/kg for HFOV [ 88 ].…”