Efficacy of noninvasive high-frequency oscillatory ventilation versus nasal intermittent positive pressure ventilation as post-extubation respiratory support in preterm infants: a Meta analysis / 中国当代儿科杂志

OBJECTIVES@#To systematically evaluate the efficacy and safety of noninvasive high-frequency oscillatory ventilation (NHFOV) versus nasal intermittent positive pressure ventilation (NIPPV) as post-extubation respiratory support in preterm infants.@*METHODS@#China National Knowledge Infrastructure, Wanfang Data, Chinese Journal Full-text Database, China Biology Medicine disc, PubMed, Web of Science, and the Cochrane Library were searched for articles on NHFOV and NIPPV as post-extubation respiratory support in preterm infants published up to August 31, 2022. RevMan 5.4 software and Stata 17.0 software were used for a Meta analysis to compare related indices between the NHFOV and NIPPV groups, including reintubation rate within 72 hours after extubation, partial pressure of carbon dioxide (PCO2) at 6-24 hours after switch to noninvasive assisted ventilation, and the incidence rates of bronchopulmonary dysplasia (BPD), air leak, nasal damage, periventricular leukomalacia (PVL), intraventricular hemorrhage (IVH), and retinopathy of prematurity (ROP).@*RESULTS@#A total of 9 randomized controlled trials were included. The Meta analysis showed that compared with the NIPPV group, the NHFOV group had significantly lower reintubation rate within 72 hours after extubation (RR=0.67, 95%CI: 0.52-0.88, P=0.003) and PCO2 at 6-24 hours after switch to noninvasive assisted ventilation (MD=-4.12, 95%CI: -6.12 to -2.13, P<0.001). There was no significant difference between the two groups in the incidence rates of complications such as BPD, air leak, nasal damage, PVL, IVH, and ROP (P>0.05).@*CONCLUSIONS@#Compared with NIPPV, NHFOV can effectively remove CO2 and reduce the risk of reintubation, without increasing the incidence of complications such as BPD, air leak, nasal damage, PVL, and IVH, and therefore, it can be used as a sequential respiratory support mode for preterm infants after extubation.

Risk factors for failure of nasal high frequency oscillatory ventilation as initial therapy in very low birth weight infants with respiratory distress syndrome / 中国新生儿科杂志

Objective:To study the risk factors of failure using nasal high frequency oscillatory ventilation (nHFOV) as initial therapy in the treatment of respiratory distress syndrome (RDS) in very low birth weight infants (VLBWIs).Methods:From January 2018 to December 2021, VLBWIs with RDS initially supported by nHFOV in NICU of our hospital were retrospectively analyzed. They were assigned into success and failure groups according to the ventilation efficacy. Demographic data and clinical outcomes of the two groups were compared. Risk factors of initial nHFOV failure were analyzed using binary Logistic regression method.Results:A total of 135 infants were included, including 103 in the success group and 32 in the failure group. The initial nHFOV failure rate was 23.7%. The failure group had lower pH (7.26±0.09 vs. 7.33±0.08) and PaO 2 [61.0 (49.6, 77.2) mmHg vs. 83.6 (64.4, 99.0) mmHg] than the success group ( P<0.05) and higher PaCO 2 than the success group [49.0 (42.3, 58.1) mmHg vs. 43.4 (36.0, 50.0) mmHg] ( P<0.05). Using PaCO 2 as predictor, the area under the curve (AUC) was 0.682 (95% CI 0.575-0.788) and the cut-off value was 44.8 mmHg for nHFOV failure and the AUC was 0.716 (95% CI 0.615-0.817) and the cut-off value was 67.1 mmHg for nHFOV success. The incidences of early onset sepsis (EOS), shock within 3 d and hemodynamically significant patent ductus arteriosus (hsPDA) in the failure group were significantly higher than the success group (40.6% vs. 7.8%, 53.1% vs. 2.9%, 31.3% vs. 13.6%, P<0.05, respectively). Binary logistic regression analysis found that PaO 2<67.1 mmHg ( OR=5.458,95% CI 1.730-17.220) on the first blood gas analysis and shock within 3 d ( OR=26.585,95% CI 3.854-183.396) were independent risk factors for initial nHFOV failure ( P<0.05). Conclusions:The failure of initial nHFOV is correlated with the first blood gas parameters, EOS, hsPDA and shock within 3 d. Shock within 3 d and low PaO 2(<67.1 mmHg) were independent risk factors for initial nHFOV failure.

Efficacy and safety of noninvasive high-frequency oscillatory ventilation in the treatment of respiratory distress syndrome in premature infants : a Meta-analysis / 中国新生儿科杂志

Objective:To evaluate the efficacy and safety of noninvasive high-frequency oscillatory ventilation (nHFOV) as the initial ventilation mode for respiratory distress syndrome (RDS) in premature infants.Methods:From the establishment of the databases [(PubMed, Embase, Cochrane Library, CNKI, Wanfang database, CQVIP and CBM (SinoMed)] to March 1, 2022, literature on randomized controlled trials (RCTs) using nHFOV and nasal continuous positive airway pressure(NCPAP) as the initial ventilation modes for RDS in premature infants were searched. The qualities of the included literature were evaluated according to Cochrane Evaluation Manual. RevMan 5.4 software was used for Meta-analysis.Results:Seven RCTs involving 786 children were included for the final Meta-analysis, with 395 cases in the nHFOV group and 391 cases in the NCPAP group. The results showed that the nHFOV group had lower intubation rates than the NCPAP group ( OR=0.34, 95% CI 0.22~0.51, P<0.001). No significant differences existed in mortality rates and complication rates between the two groups ( P>0.05). Conclusions:nHFOV as the initial treatment for RDS in premature infants may reduce the incidence of early treatment failure without increasing complications.

Outcome of Neonates with Meconium Aspiration Syndrome on High Frequency Oscillatory Ventilation in NICU of Tertiary Care Centre

Background: Meconium Aspiration Syndrome (MAS) is a complex respiratory disease of the term and near-term neonate. Inhalation of meconium causes airway obstruction, atelectasis, epithelial injury, surfactant inhibition and pulmonary hypertension, the chief clinical manifestations of which are hypoxemia and poor lung compliance. Supplemental oxygen is the mainstay of therapy of MAS, with around one-third of infants requiring mechanical ventilation. For those ventilated, high ventilator pressures, as well as relatively long inspiratory time and slow ventilatory rate, may be necessary to achieve adequate oxygenation. High frequency ventilation may offer a benefit in infants with refractory hypoxemia and/or gas trapping. High-frequency oscillatory ventilation (HFOV) is a lung-protective strategy that can be utilized in the full spectrum of patient populations ranging from neonatal to adults with acute lung injury. HFOV uses low tidal volumes and constant mean airway pressures in conjunction with high respiratory rates to provide beneficial effects on oxygenation and ventilation, while eliminating the traumatic “inflate–deflate” cycle imposed by CV. Few studies have shown that, HFOV can effectively improve lung ventilation and oxygenation function, shorten ventilator treatment time and reduce the incidence of air leakage for neonatal MAS, making it a safe and effective treatment method. Objective:To study the Outcome of Neonates with Meconium Aspiration Syndrome on High Frequency Oscillatory Ventilation (HFVO).Material & Methods:It is a Prospective Observational Study of 10 neonates >34 weeks of gestation and birth weight >1500gm with meconium-stained liquor with respiratory distress requiring mechanical ventilation. Study was conducted over a period of 10months from August 2021 to May 2022. These neonates requiring mechanical ventilation were electively first hand put on SensorMedics 3100A High Frequency Oscillatory Ventilator after taking informed written consent from parents and given appropriate Intensive care. Data was analyzed at the end of the study duration and looked for outcome in the form of successful weaning from mechanical ventilation and discharge from NICU, and Death.Results:8 out of 10 (80%) neonates with MAS that were ventilated via HFOV were successfully weaned from mechanical ventilation and discharged, while death was reported in 2 out of 10 (20%) of the neonates included in the study.Conclusion:80% of neonates with MAS that were provided mechanical ventilation in the form of HFOV were effectively weaned off from mechanical ventilation, whereas 20% neonates died. This shows clinical effectiveness of HFOV in MAS making it a safe and effective treatment modality in neonates with MAS.

Application of noninvasive high-frequency oscillatory ventilation in the treatment of neonatal respiratory failure: a review / 预防医学

Abstract@#As a common critically illness among neonates and notably premature infants, respiratory failure is one of the major factors for neonatal deaths. Ventilator, an effective tool for assisted ventilation, is effective to remarkably improve respiratory failure; however, the conventional mechanical ventilation is likely to cause a series of injuries and complications. Therefore, noninvasive ventilation is commonly used in clinical practices. Noninvasive high-frequency oscillatory ventilation is an emerging noninvasive respiratory, in which tracheal intubation is replaced with nasal plug and mask to transfer high-frequency airflow to the airway. It facilities rapid correction of the imbalance of ventilation blood flow ratio, reduction of carbon dioxide retention, increase in oxygen saturation, and reduction in incidence of complications and risk of failure in ventilator withdrawal, which has been employed for the treatment of respiratory failure among neonates. The review descries the applications of noninvasive high-frequency oscillatory ventilation in respiratory support among neonates with respiratory failure, so as to provide insights into the management of respiratory failure among neonates.

Early application of non-invasive high frequency oscillatory ventilation in very low birth weight infants with respiratory distress syndrome / 中华实用儿科临床杂志

Objective:To observe the clinical efficacy and safety of non-invasive high frequency oscillatory ventilation(NHFOV) on the early respiratory support in very low birth weight infants with respiratory distress syndrome(RDS).Methods:It was a prospective cohort study involving very low birth weight infants with RDS admitted to the Central Hospital of Chongqing Three Gorges from January 2017 to January 2020 with a gestational age of 28-32 weeks.According to the applied non-invasive respiratory support, very low birth weight infants with NRDS were divided into control group[continuous positive airway pressure (CPAP) group]and observation group(NHFOV group). Therapeutic effect, complications and adverse effects between 2 groups were compared.Results:A total of 78 very low birth weight infants with RDS were included, among which 38 cases were supported with NHFOV group and 40 cases were CPAP group.(1) Therapeutic efficacy: there were no significant differences in the use of pulmonary surfactant and death rate between 2 groups (all P>0.05). Compared with the CPAP group, patients in the NHFOV group had significantly lower incidence of non-invasive ventilation failure(4 cases vs.13 cases), duration of non-invasive ventilation [(7.60±1.68) days vs. (10.75±2.38) days], duration of oxygen exposure [(12.34±2.66) days vs.(17.20±4.36) days] and times of apnea [(1.68±1.57) times/day vs.(4.80±2.60) times/day] (all P<0.05). There was no significant difference in the incidence of complications between 2 groups (all P>0.05). (2) Adverse events: compared with CPAP group, patients in the NHFOV group had significantly lower incidence of abdominal distension [13 cases(34.2%) vs. 25 cases (62.5%)], delayed duration of respiratory secretion disappearance [(12.65±2.33) days vs.(7.87±2.70) days], low viscosity of secretions [thin sputum, 31 cases (81.6%) vs.22 cases (55.0%); ropy sputum, 7 cases (18.4%) vs.18 cases(45.0%)], and less airway obstruction [2 cases (5.2%) vs.15 cases (37.5%)] (all P<0.05). No significant difference in the incidence of nasal septum injury was detected between 2 groups (1 case vs.0) ( P>0.05). Conclusions:NHFOV is safe and effective in the early application of NRDS in very low birth weight infants with RDS, which has less adverse events.It is expected to be used in the treatment of children with frequent apnea and a large number of respiratory secretions that is prone to obstruction.

Effective Tidal Volume for Normocapnia in Very-Low-Birth-Weight Infants Using High-Frequency Oscillatory Ventilation

PURPOSE: Removal of CO₂ is much efficient during high-frequency oscillatory ventilation (HFOV) for preterm infants. However, an optimal carbon dioxide diffusion coefficient (DCO₂) and tidal volume (VT) have not yet been established due to much individual variance. This study aimed to analyze DCO₂ values, VT, and minute volume in very-low-birth-weight (VLBW) infants using HFOV and correlates with plasma CO₂ (pCO₂). MATERIALS AND METHODS: Daily respiratory mechanics and ventilator settings from twenty VLBW infants and their two hundred seventeen results of blood gas analysis were collected. Patients were treated with the Dräger Babylog VN500 ventilator (Drägerwerk Ag & Co.) in HFOV mode. The normocapnia was indicated as pCO₂ ranging from 45 mm Hg to 55 mm Hg. RESULTS: The measured VT was 1.7 mL/kg, minute volume was 0.7 mL/kg, and DCO₂ was 43.5 mL²/s. Mean results of the blood gas test were as follows: pH, 7.31; pCO₂, 52.6 mm Hg; and SpO₂, 90.5%. In normocapnic state, the mean VT was significantly higher than in hypercapnic state (2.1±0.5 mL/kg vs. 1.6±0.3 mL/kg), and the mean DCO₂ showed significant difference (68.4±32.7 mL²/s vs. 32.4±15.7 mL²/s). The DCO₂ was significantly correlated with the pCO₂ (p=0.024). In the receiver operating curve analysis, the estimated optimal cut-off point to predict the remaining normocapnic status was a VT of 1.75 mL/kg (sensitivity 73%, specificity 80%). CONCLUSION: In VLBW infants treated with HFOV, VT of 1.75 mL/kg is recommended for maintaining proper ventilation.

Application of noninvasive high frequency oscillatory ventilation in neonates with meconium aspiration syn-drome with pulmonary hypertension after extubation / 实用医学杂志

Objective To investigate the clinical value of nasal noninvasive high frequency oscillatory ven-tilation(NHFOV)as a respiratory support after exbutation by comparing it with nasal continuous positive airway pressure(NCPAP)in neonates with meconium aspiration syndrome(MAS)and persistent pulmonary hypertension (PPHN).Methods Infants of MAS with PPHN after exbutation from intensive care unit were randomly divided in-to NHFOV and NCPAP groups. The value of blood oxygen Pressure(PaO2),carbon dioxide partial pressure(Pa-CO2)and PaO2/FiO2at 1 h,12 h,24 h after exbutation were monitored.Results The NHFOV group showed low-er PaCO2than the NCPAP group at 1 h,12 h and 24 h after noninvasive respiratory support[1 h:(41.1 ± 7.2)vs. (45.4 ± 6.7),P=0.000;12 h:(38.9 ± 3.1)vs.(44.6 ± 5.2),P=0.000;24 h:(35.1 ± 8.2)vs.(43.2 ± 7.1),P=0.000].There were no statistically significant difference of both PaO2and PaO2/FiO2at 1 h,12 h,24 h between the two groups(P>0.05).11.43% infants were failed to be extubated in NHFOV group,but 35.29% in NCPAP group, and there was significant difference between the two groups(P=0.021). Conclusion Compared with NCPAP, NHFOV can better reduce carbon dioxide retention in the sequential therapy for neonates after extubation,and it can also decrease the rate of extubation failure.

Progress of high frequency oscillatory ventilation in pediatric acute respiratory distress syndrome / 国际儿科学杂志

Pediatric acute respirator distress syndrome (PARDS) is a common critical disease in children with a high mortality.High frequency oscillatory ventilation (HFOV) has been considered as an ideal ventilation mode for the treatment of PARDS,which has the function of protecting lung,improving oxygenation and reducing pulmonary inflammation.This article reviews the progress and status of HFOV in the application of PARDS.

High-frequency oscillatory ventilation in children with measles complicated with severe pneumonia and the acute respiratory distress syndrome / 中国小儿急救医学

Objective To explore the effectiveness and safety of high frequency oscillatory ventilation(HFOV) in children with measles complicated with severe pneumonia and the acute respiratory distress syndrome(ARDS).Methods A total of 63 children with measles complicated with severe pneumonia and the ARDS were divided into conventional mechanical ventilation(CMV) group and HFOV group.The PaO2/ FiO2,oxygenation index (OI),HR and mean arterial pressure (MAP) before treatment and 12 h,24 h,48 h after treatment were detected.The rate of air leak and the motality in two groups were compared.The efficacy and safety of HFOV treatment were evaluated in children with measles complicated with pneumonia and severe ARDS.Results In HFOV group,the PaO2/FiO2 ratio was elevated and OI was decreased significantly after 12 h and maintained for at least 48 h.Compared with CMV group,OI of HFOV group improved more significantly,and the difference was statistically significant.The ventilation time in HFOV group was shorten than that in CMV group[(7.97 ±3.06) d vs.(11.03 ±3.60) d],but there was no statistical difference between two groups (P ＞ 0.05).The heart rate after treatment 48 h was gradually returned to normal,and there was no statistical difference between the two groups.There were no significant changes in the MAP of two groups after treatment.There were no significant differences in the incidence of air leak between the CMV group and the HFOV group(24.2％ vs.16.7％).The mortality rate of CMV group and HFOV group was respectively 45.5 ％ and 33.3 ％,and there was no statistically significant difference.Conclusion HFOV was effective in oxygenation and seems to be safe for pediatric patients with measles complicated with severe pneumonia and the ARDS.Also it didn't influence the occurrence of complications.It has no adverse influence on hemodynamic parameters.Early intervention of HFOV is safe and effective for the children with measles complicated with severe pneumonia and ARDS.

Clinical study of high frequency oscillatory ventilation combined thoracic close drainage for the treatment of 22 cases of neonatal pneumothorax / 中国综合临床

Objective To explore the clinical effect and safety of high frequency oscillatory ventilation (HFOV) combined thoracic close drainage for the treatment of mechanical ventilated neonates with pneumothorax.Methods Twenty-two neonates were enrolled in this study,who needed mechanical ventilation diagnosed with neonatal pneumothorax and received treatment of HFOV combined thoracic close drainage from Jan.2012 and Jun.2014 in the People's Hospital of Dongguan.We recorded blood gas analysis and parameters of breathing machine before using HFOV and 2,12,24,48 hours after using HFOV respectively.Results There were significant differences between HFOV before use (0) and 2,12,24,48 hours after using HFOV in terms of blood pH value,arterial partial pressure of oxygen(PaO2),partial pressure of arterial carbon dioxide (PaCO2),oxygenation index (OI),the inspired oxygen concentration (FiO2),mean airway pressure (MAP) (F =6.606,17.760,8.387,17.242,25.185; P ＜ 0.05).Compared with before using HFOV combined thoracic close drainage,PaO2 was significantly increased from (51.25 ± 13.16) mmHg to (62.60 ± 15.95) mmHg.PaCO2 was significantly dropped from (63.57 ± 13.81) mmHg to (54.02 ± 11.58) mmHg and OI was dropped sharply from (16.57 ± 9.09) to (11.28 ± 4.67) at 2 hours after using HFOV combined thoracic close drainage (P ＜ 0.05).FiO2 significantly decreased from (0.76 ± 0.15) to (0.60 ± 0.13),as well as MAP from (9.91 ± 1.44) cm H2 Oto (8.50 ± 1.68) cm H2O.Furthermore,pH was significantly improved from (7.24 ± 0.15) to (7.34 ±0.10) at 12 hours later(P ＜0.05).PH,PaO2,PaCO2 were roughly back to normal at 48 hours after treatment.The main complications were intraventricular hemorrhage (2 cases),subarachnoid hemorrhage (2 cases),ventilator associated pneumonia (1 case) and pulmonary hemorrhage (1 case) (not during the time of HFOV treatment).Conclusion HFOV combined thoracic close drainage for the treatment of neonates with pneumothorax is safety and effective methods.

High-frequency oscillatory ventilation in children with hematologic neoplasms and other causes induced acute hypoxic respiratory failure / 中国小儿急救医学

Objective To evaluate the significance of high-frequency oscillatory ventilation(HFOV) used in acute hypoxic respiratory failure(AHRF) children,failing to conventional ventilation.Methods This was a retrospective study of AHRF children ventilated by HFOV from January 2011 to September,2013.All patients were initially treated by conventional mechanical ventilation (CMV),and changed to be treated by HFOV if the patient met to one of the following criteria after the CMV parameters of PIP ＞ 30 mmH2O(1cmH2O =0.098 kPa) or PEEP ＞ 10 cmH2O with FiO2 100％ ∶ (1) SpO2 ＜ 90％ or PaO2 ＜ 60 mmHg (1 mmHg =0.133 kPa) ; (2) severe respiratory acidosis (PaCO2 ＞ 80 mmHg) ; (3) serious air leakage (mediastinal emphysema or pneumothorax).The following parameters were recorded:patient's gender,age,living PICU time,CMV ventilation time,HFOV ventilation time.We reviewed ventilation parameter settings (MAP,△P,F,FiO2),oxygenation index(PaO2/FiO2,OI),arterial blood gas,heart rate,blood pressure at different time points including late CMV(H0),2 h after HFOV(H2),6 h after HFOV(H6),12 h after HFOV(H12),24 h after HFOV (H24) and 48 h after HFOV (H48),respectively.Various indexes at different time points were compared between survival group and death group,oncology group and no-oncology group.Results PaO2 at H2 compared with H0 had significant improvement[76.9(61.9 ～ 128.0) mmHg vs 50.1 (49.5 ～68.0) mmHg,P =0.006] . PaO2/FiO2 at H2,H48 had significant improvement compared with those at H0,H24 [94.9(66.8 ～ 138.9) mmHg vs 68.0(49.5 ～86.8) mmHg,P=0.039; 135.0(77.6～240.0) mmHg vs 90.7 (54.6 ～161.7) mmHg,P =0.023)].All children's systolic pressure,diastolic blood pressure,heart rate at various time points had no difference (P ＞0.05).Compared to death group(n =14),PaO2/FiO2,OI at H6,H12,H24,H48 in survival group (n =9) had significant improvement(P ＜ 0.05).Compared to oncology group (n =10),OI at H2,H6 in no-oncology group(n =10) had significant improvement [(19.2 (13.9 ～ 26.6) vs 33.8 (19.7 ～ 48.3),P =0.049 ; 16.0(8.4 ～27.1) vs 28.9(20.9 ～38.9),P =0.027)],and mean airway pressure between two groups at H2,H6,H12 had significant improvement(P ＜ 0.05).Mortality had no significant differcence between two groups (4/10 vs 10/13,P =0.086).Conelusion HFOV used in children with AHRF which had failed with CMV ventilation can improve the patient's PaO2 and OI.Heart rate and blood pressure are stable during HFOV treatment.Oncology group patients needed higher initial MAP to improve oxygenation than no-oncology group patients when changed to HFOV treatment,but the mortality showed no difference between two groups.

Ventilação oscilatória de alta frequência em crianças com síndrome da angústia respiratória aguda: experiência de um centro de tratamento intensivo pediátrico / High-frequency oscillatory ventilation in children with acute respiratory distress syndrome: experience of a pediatric intensive care unit

OBJETIVO: Descrever os efeitos da aplicação da ventilação de alta frequência oscilatória como suporte ventilatório de resgate em uma série de pacientes pediátricos com síndrome da angústia respiratória aguda (SARA). MÉTODOS: Participaram do estudo 25 crianças(> 1mês e < 17 anos) internadas em uma UTI pediátrica universitária com SARA e submetidas à ventilação de alta frequência oscilatória (VAFO) por um mínimo de 48 horas, após falha da ventilação mecânica convencional. RESULTADOS: A taxa de mortalidade foi de 52% (13/25) 28 dias após o início da SARA. Ao longo de 48 horas, a aplicação da VAFO reduziu o índice de oxigenação [38 (31-50) vs. 17 (10-27)] e aumentou a relação pressão arterial parcial de O2/fração inspirada de O2 [65 (44-80) vs. 152 (106-213)]. A pressão arterial parcial de CO2 [54 (45-74) vs. 48 (39-58) mmHg] manteve-se inalterada. A pressão média de vias aéreas oscilou entre 23 e 29 cmH2O. A VAFO não comprometeu a hemodinâmica e observou-se uma redução da frequência cardíaca (141 ± 32 vs. 119 ± 22 bat/min), a pressão arterial média (66 ± 20 vs. 71 ± 17 mmHg) e o escore inotrópico [44 (17-130) vs. 20 (16-75)] mantiveram-se estáveis nesse período. Nenhum sobrevivente ficou dependente de oxigênio. CONCLUSÃO: VAFO melhora a oxigenação de pacientes pediátricos com SARA grave e hipoxemia refratária ao suporte ventilatório convencional.

OBJECTIVE: To describe the effects of high-frequency oscillatory ventilation (HFOV) as a rescue Acute respiratory distress syndrome ventilatory support in pediatric patients with acute respiratory distress syndrome (ARDS). METHODS: Twenty-five children (1 month < age < 17 years) admitted to a university hospital pediatric intensive care unit (ICU) with ARDS and submitted to HFOV for a minimum of 48 hours after failure of conventional mechanical ventilation were assessed. RESULTS: Twenty eight days after the onset of ARDS, the mortality rate was 52% (13/25). Over the course of 48 hours, the use of HFOV reduced the oxygenation index [38 (31-50) vs. 17 (10-27)] and increased the ratio of partial arterial pressure O2 and fraction of inspired O2 [65 [44-80) vs. 152 (106-213)]. Arterial CO2 partial pressure [54 (45-74) vs. 48 (39-58) mmHg] remained unchanged. The mean airway pressure ranged between 23 and 29 cmH2O. HFOV did not compromise hemodynamics, and a reduction in heart rate was observed (141±32 vs. 119±22 beats/min), whereas mean arterial pressure (66±20 vs. 71±17mmHg) and inotropic score [44 (17-130) vs. 20 (16-75)] remained stable during this period. No survivors were dependent on oxygen. CONCLUSION: HFOV improves oxygenation in pediatric patients with ARDS and severe hypoxemia refractory to conventional ventilatory support.

Ventilação oscilatória de alta frequência em crianças: uma experiência de 10 anos / High-frequency oscillatory ventilation in children: a 10-year experience

OBJETIVOS: O objetivo do estudo foi descrever a experiência com ventilação oscilatória de frequência (VOAF) em uma unidade portuguesa de Cuidados Intensivos Neonatais e Pediátricos e avaliar se a VOAF permitiu uma melhoria na oxigenação e na ventilação. MÉTODOS: Estudo de coorte retrospectivo observacional em crianças submetidas À ventilação com VOAF entre janeiro de 2002 e dezembro de 2011. Os seguintes parâmetros foram registrados: dados demográficos e clínicos; gases sanguíneos; e parâmetros ventilatórios durante as primeiras 48 horas de VOAF. RESULTADOS: O estudo incluiu 80crianças com uma idade média de 1,5 mês (mínima: uma semana; máxima: 36 meses). Pneumonia (n = 50; 62,5%) e bronquiolite (n = 18; 22,5%) foram os principais diagnósticos. Cerca de 40% (n = 32) dos pacientes desenvolveram a síndrome da angústia respiratória aguda (SARA). A ventilação mecânica convencional foi utilizada em 68 (85%) pacientes antes da VOAF. Todos os pacientes que começaram a VOAF tiveram hipoxemia, e 56 (70%) também apresentaram hipercapnia persistente. Duas horas após o início da VOAF, foi observada uma melhoria significativa na proporção SatO2/FiO2 (128 ± 0,63 em comparação a 163 ± 0,72; p < 0,001), que foi mantida durante as 24 horas de VOAF, e uma redução da FiO2. Desde o início da VOAF, a PCO2 média teve uma queda significativa (87 ± 33 em comparação a 66 ± 25; p < 0,001) e o pH aumentou significativamente (7,21 ± 0,17 em comparação a 7,32 ± 0,15; p < 0,001). A sobrevida geral foi de 83,8%. CONCLUSÕES: A VOAF permitiu uma melhoria na hipercapnia e na oxigenação. Trata-se de uma opção segura no tratamento da SARA e de doenças graves das pequenas vias aéreas.

OBJECTIVES: The aim of the study was to describe the experience with high-frequency oscillatory ventilation (HFOV) in a Portuguese Pediatric Critical Care Unit, and to evaluate whether HFOV allowed improvement in oxygenation and ventilation. METHODS: This was a retrospective observational cohort study of children ventilated by HFOV between January, 2002 and December, 2011. The following parameters were recorded: demographic and clinical data, and blood gases and ventilatory parameters during the first 48 hours of HFOV. RESULTS: 80 children were included, with a median age of 1.5 months (min: one week; max: 36 months). Pneumonia (n = 50; 62.5%) and bronchiolitis (n = 18; 22.5%) were the main diagnoses. Approximately 40% (n = 32) of the patients developed acute respiratory distress syndrome (ARDS). Conventional mechanical ventilation was used in 68 (85%) of patients prior to HFOV. All patients who started HFOV had hypoxemia, and 56 (70%) also presented persistent hypercapnia. Two hours after starting HFOV, a significant improvement in SatO2/FiO2 ratio (128 ± 0.63 vs. 163 ± 0.72; p < 0.001) that was sustained up to 24 hours of HFOV and a decrease in FiO2 were observed. Since the beginning of HFOV, the mean PCO2 significantly decreased (87 ± 33 vs. 66 ± 25; p < 0.001), and the pH significantly improved (7.21 ± 0.17 vs. 7.32 ± 0.15; p < 0.001). Overall survival was 83.8%. CONCLUSIONS:HFOV enabled an improvement in hypercapnia and oxygenation. It is a safe option for the treatment of ARDS and severe small airway diseases.

Three kinds of mechanical ventilations for treating neonatal respiratory distress syndrome / 中华实用儿科临床杂志

Objective To contrast the curative effects of proportional assist ventilation (PAV) and high frequency oscillatory ventilation(HFOV) and synchronized intermittent mandatory ventilation(SIMV) on treatment of neonatal respiratory distress syndrome(NRDS).Methods A retrospective study was carried out based on clinical data of 161 neonates.The research subjects were the neonates who had been hospitalized from May 2008 to May 2012 in Jiangmen Central Hospital and received one of the mechanical ventilation methods.The subjects were divided into 3 groups according to used mechanical ventilation mode they received,and their curative effect was compared.Results Fortythree cases in PAV group were treated by PAV,58 cases in HFOV group received HFOV,and 60 cases in SIMV group received SIMV.In comparison with sex ratio,gestational age of birth,birth weight,dose of poractant alfa injection there was no differece among 3 groups(all P ＞0.05).The number of effective cases in PAV group,HFOV group and SIMV group was 37 cases,57 cases,52 cases,respectively;the invalid cases including 6 cases,1 case,8 cases in 3 groups,respectively.Among the 3 groups,the curative effect was significantly different(x2 =6.197,P =0.045),curative effect of PAV group was not different from that of SIMV group(x2 =0.008,P =0.928),curative effect of HFOV group was better than that of PAV group and SIMV group(x2 =3.986,P =0.046 ;x2 =4.114,P =0.043).Conclusion The curative effect of HFOV for neonatal respiratory distress syndrome was better,which could be recommended.

High frequency oscillatory ventilation combined with inhaled nitric oxide on neonates with severe meconium aspiration syndrome / 中国小儿急救医学

Objective To investigate the effects of high frequency oscillatory ventilation (HFOV)combined with inhaled nitric oxide(iNO) on neonates with severe meconium aspiration syndrome(MAS).Methods Sixty newborn infants with severe MAS admitted to the neonatal intensive care unit of Shenzhen Children's Hospital from Oct 2008 to May 2011 were included for this study.All of them needed mechanical ventilation after birth and oxygenation index (OI) ＞ 30.According to the different ventilation modes,they were randomly divided into conventional mechanical ventilation (CMV) group,HFOV group and HFOV combined with iNO (HFOV + iNO) group,each group had twenty neonates.OI and the rate of air leak and pulmonary hypertension in each group were compared.Results Ventilation after 24 h,OI of HFOV group and HFOV + iNO group were significantly decreased as compared with CMV group (19.0 ± 4.5 vs 11.0 ± 5.3 vs 25.0 ± 7.1,P ＜ 0.05).In HFOV + iNO group,the obvious decline of OI(from 36.0 ± 7.4 to 24.0 ± 5.2) were observed at four hours after treatment.The rate of air leak in HFOV and HFOV + iNO groups was both zero as compared with CMV (5/20,25％).The rate of pulmonary hypertension in HFOV + iNO group was zero and the HFOV group was 30％ (6/20),the CMV group was 40％ (8/20).Conclusion HFOV combined with iNO was preferred treatment for neonates with severe MAS,and they have synergistic effect.

Ventilación de alta frecuencia oscilatoria (VAFO): experiencia inicial en una unidad de cuidados intensivos neonatales / High-frequency oscillatory ventilation (HFOV): initial experiences of a neonatal intensive care unit

Introducción: La Ventilación de Alta Frecuencia Oscilatoria (VAFO) ha surgido como una alternativa en el tratamiento de diversas formas de falla respiratoria, ante el fracaso de la ventilación Mecánica Convencional. Objetivo: Describir la experiencia de un servicio de Neonatología en la utilización de un ventilador de alta frecuencia, según criterios de dificultad en la ventilación, valores de índice de oxigenación y/o valores de PMVA. Materiales y Métodos: Estudio observacional, descriptivo y analítico. Se incluyeron recién nacidos con el diagnóstico de insuficiencia respiratoria severa, con Índice de Oxigenación (IO) mayor de 20 o Presión Media Vía Área mayor (PMVA) de 12 en cm de H2O. Resultados: En el periodo de estudio comprendido entre marzo 2008 y marzo 2009, en 9 pacientes se decidió el uso de VAFO, de los cuales fueron excluidos 2 pacientes por haber fallecido antes de la hora de instalada la terapéutica, por causas no atribuibles al uso de la VAFO; en los 7 pacientes restantes se obtuvieron los siguientes resultados: edad promedio 35 semanas (26-41), peso promedio 2310 grs.(850-3810); el IO (índice de oxigenación) de ingreso a VAFO promedio fue de 33,6, con valores que variaron entre un máximo de 50 y un mínimo de 15. Con relación a la pO2 se observó una mejoría post VAFO en 6/7 (90%) mayor de 20 mmHg dentro de la primera hora. La sobrevida fue 3/7 (43%). Conclusiones: Si bien se observó mejoría en la oxigenación, en la ventilación y en el índice de oxigenación luego del ingreso de los pacientes a la VAFO, sin embargo la sobrevida no fue buena 3/7 (43%).

Introduction: High-frequency oscillatory ventilation (HFOV) has become an alternative for various types of respiratory failure due to the failure of conventional mechanical ventilation.Objective: To assess the results of high-frequency oscillatory ventilation (HFOV) as resuscitative therapy for severe respiratory failure in newborns at a neonatal unit. Materials and Methods: A descriptive, analytic, observational study. Newborns were included with a diagnosis of severe respiratory insufficiency with an oxygenation index (OI) greater than 20 or a mean airway pressure (MAP) of 12 cm H2O. Results: During the study period lasting from March 2008 to March 2009, it was decided to use HFOV for 9 patients, of whom 2 were excluded due to death before use of HFOV therapy for unrelated causes. The remaining 7 patients had a mean age of 35 weeks, (range: 26-41 weeks), average weight of 2310 grams (range: 850-3810 grams), and an average OI on presentation of 33.6 with values of a maximum of 50 and a minimum of 1.5. Post-HFOV improvement greater than 20 mmHg PO2 was seen in 6 of 7 (90%) within the first hour. The survival ate was 43% (3 of 7).

High-frequency oscillatory ventilation for acute respiratory distress syndrome.

Objective. To evaluate the effectiveness of HFOV in pediatric patients with acute respiratory distress syndrome. Methods. In this retrospective study, we reviewed all 20 pediatric patients, who were consecutively ventilated with HFOV in the pediatric intensive care unit of a tertiary medical center, from January 2006 to February 2007. Results. A total of 20 patients were enrolled. The median age of the subjects was 70 (3-168) months; 10 were male. All patients received conventional ventilation before HFOV. After initiation of HFOV, there was an immediate and sustained increase in PaO2/FiO2 ratio. The PaO2/FiO2 ratio was elevated and OI was decreased significantly after 10-20 minutes and maintained for at least 48 hours (p= 0.03, both). Thirteen of the 20 patients were successfully weaned. No significant change in the mean arterial pressure and heart rate was noted after HFOV. Overall survival rate was 65%. Of 20 patients, 11 patients suffered from extrapulmonary ARDS (ARDSexp) and 9 from pulmonary ARDS (ARDSp). When HFOV was initiated, there was significant increase in PaO2/FiO2 and decrease in OI in ARDSexp compared to ARDSp (p= 0.03, both). Also mortality rate was significantly lower in patients with ARDSexp (9% vs.66%), (p= 0.01). Conclusion. In our study, HFOV was effective in oxygenation and seems to be safe for pediatric ARDS patients. HFOV affected ARDSp and ARDSexp paediatric patients differently. However prospective, randomized controlled trials are needed to identify its benefits over conventional modes of mechanical ventilation.

Ventilação oscilatória de alta freqüência em pediatria e neonatologia / High-frequency oscillatory ventilation in pediatrics and neonatology

Este trabalho teve por objetivo rever a literatura e descrever a utilização da ventilação oscilatória de alta freqüência em crianças e recém-nascidos. Revisão bibliográfica e seleção de publicações mais relevantes sobre ventilação de alta freqüência utilizando as bases de dados MedLine e SciElo publicadas nos últimos 15 anos. As seguintes palavras-chave foram utilizadas: ventilação oscilatória de alta freqüência, ventilação mecânica, síndrome do desconforto respiratório agudo, crianças e recém-nascidos. Descreveu-se o emprego da ventilação oscilatória de alta freqüência em crianças com síndrome do desconforto respiratório agudo, síndrome de escape de ar e doença pulmonar obstrutiva. Avaliou em recém-nascidos, síndrome do desconforto respiratório, displasia broncopulmonar, hemorragia peri-intraventricular, leucoencefalomalácia e extravasamento de ar. Também, abordou a transição da ventilação mecânica convencional para a ventilação de alta freqüência e o manuseio específico da ventilação de alta freqüência quanto à oxigenação, eliminação de gás carbônico, realização de exame radiológico, realização de sucção traqueal e utilização de sedação e bloqueio neuromuscular. Foram abordados o desmame deste modo ventilatório e as complicações. Em crianças maiores a ventilação oscilatória de alta freqüência é uma opção terapêutica, principalmente na síndrome do desconforto respiratório agudo, devendo ser empregada precocemente. Também pode ser útil em casos de síndrome de escape de ar e doença pulmonar obstrutiva. Em recém-nascidos, não há evidências que demonstram superioridade da ventilação oscilatória de alta freqüência em relação à ventilação convencional, sendo a síndrome de escape de ar a única situação clínica em que há evidência de melhores resultados com este modo ventilatório.

This article intends to review literature on high frequency oscillatory ventilation and describe its main clinical applications for children and neonates. Articles from the last 15 years were selected using MedLine and SciElo databases. The following key words were used: high frequency oscillatory ventilation, mechanical ventilation, acute respiratory distress syndrome, children, and new-born. The review describes high frequency oscillatory ventilation in children with acute respiratory distress syndrome, air leak syndrome, and obstructive lung disease. Respiratory distress syndrome, bronchopulmonary dysplasia, intracranial hemorrhage, periventricular leukomalacia, and air leak syndrome were reviewed in neonates. Transition from conventional mechanical ventilation to high frequency ventilation and its adjustments relating to oxygenation, CO2 elimination, chest radiography, suctioning, sedatives and use of neuromuscular blocking agents were described. Weaning and complications were also reported. For children, high frequency oscillatory ventilation is a therapeutic option, particularly in acute respiratory distress syndrome, and should be used as early as possible. It may be also useful in the air leak syndrome and obstructive pulmonary disease. Evidence that, in neonates, high frequency oscillatory ventilation is superior to conventional mechanical ventilation is lacking. However there is evidence that better results are only achieved with this ventilatory mode to manage the air leak syndrome.

Therapeutic Effect of High Frequency Oscillatory Ventilation on Premature Infants with Respiratory Distress Syndrome / 实用儿科临床杂志

Objective To evaluate the effect of the high frequency oscillatory ventilation(HFOV) on the treatment of premature neonates with respiratory distress syndrome(RDS).Methods Seventy premature infants with RDS were randomly grouped as HFOV group(n=33) and conventional mandatory ventilation group(CMV group,n=37),based on their fetal age,weight,age,and their clinical condition from Jan.to Sep.in 2009.The blood gas analysis was detected and compared between the 2 groups.Results In HFOV group,the inhaled oxygen concentration,pa(CO2) decreased after treatment for 6 h,which were significantly lower than those at the beginning of the therapy(Pa