早产儿呼吸窘迫综合征高频振荡通气后两种撤机方式的安全性研究：前瞻性随机对照试验

目的 探讨高频振荡通气（HFOV）治疗早产儿呼吸窘迫综合征（RDS）后两种撤机方式的安全性。方法 前瞻性纳入2019年1月1日至2020年6月30日厦门市妇幼保健院新生儿科重症监护病房（NICU）收治的胎龄≤ 32⁺⁶周或体重≤ 1 500 g、首选HFOV治疗的RDS早产儿101例,随机分为HFOV直接撤机组（观察组）50例,HFOV转为常频机械通气撤机组（对照组）51例。比较两组患儿撤机后72 h内的撤机失败率,撤机前2 h、撤机后2 h、撤机后24 h的血气分析各指标,比较两组呼吸支持治疗情况、并发症的发生率及出院时的转归情况。结果 观察组和对照组撤机失败率差异无统计学意义（8% vs 14%,P > 0.05）。观察组有创机械通气时间较对照组缩短[（64±39）h vs（88±69）h,P < 0.05]。两组患儿总机械通气时间、总用氧时间、撤机前后的血气分析各指标、并发症发生率、出院时转归情况差异均无统计学意义（均P > 0.05）。结论 对于RDS早产儿,使用HFOV后采取直接撤机策略是安全可靠的,且可减少有创呼吸机使用时间,值得临床推广应用。     

Lung Function and Respiratory Health at School Age in Ventilated Very Low Birth Weight Infants

Objective

To investigate respiratory health and lung function in school-aged children without broncho-pulmonary dysplasia (BPD), who were very low birth weight (VLBWi) and randomized at birth to high frequency oscillatory ventilation (HFOV) or volume guarantee (VG) ventilation for severe respiratory distress syndrome (RDS).

Methods

In this observational study, 7-y-old ex-preterm infants with severe RDS, randomly assigned at birth to receive assisted/control ventilation?+?VG (Vt?=?5 mL/kg, PEEP?=?5 cmH₂O)(VG group; mean GA 27?±?2 wk; mean BW 1086?±?158 g) or HFOV (HFOV group; mean GA: 27?±?2; mean BW: 1090?±?139 g) (both groups were ventilated with Drager Babylog 8000 plus) were recalled. Neonatal clinical data and outcome were known. Actual outcomes were investigated with an interview; lung function was measured by whole-body plethysmography.

Results

Twenty five children were studied (VG group, n?=?13 vs. HFOV group, n?=?12). There were no differences in anthropometric data, drugs (steroids/bronchodilators and antibiotics) or hospital readmission for respiratory disorders. Compliance to the test was adequate. The authors found a similar obstructive deficit (elevated values: airway resistance (RAW), residual volume (RV), total lung capacity (TLC) with near-normal spirometry) in both groups suggesting a persistent airflow limitation even in absence of BPD.

Conclusions

VLBW infants even in absence of BPD, need long term respiratory follow-up, because they frequently show an impairment of lung function, independent from initial respiratory support, even if at birth the choice is a lung protective approach (e.g., HFOV or VG ventilation).     

High-Frequency Oscillatory Ventilation for Cardiac Surgery Children With Severe Acute Respiratory Distress Syndrome

Acute respiratory distress syndrome (ARDS) in children after open heart surgery, although uncommon, can be a significant source of morbidity. Because high-frequency oscillatory ventilation (HFOV) had been used successfully with pediatric patients who had no congenital heart defects, this therapy was used in our unit. This report aims to describe a single-center experience with HFOV in the management of ARDS after open heart surgery with respect to mortality. This retrospective clinical study was conducted in a pediatric intensive care unit. From October 2008 to August 2012, 64 of 10,843 patients with refractory ARDS who underwent corrective surgery at our institution were ventilated with HFOV. Patients with significant uncorrected residual lesions were not included. No interventions were performed. The patients were followed up until hospital discharge. The main outcome measure was survival to hospital discharge. Severe ARDS was defined as acute-onset pulmonary failure with bilateral pulmonary infiltrates and an oxygenation index (OI) higher than 13 despite maximal ventilator settings. The indication for HFOV was acute severe ARDS unresponsive to optimal conventional treatment. The variables recorded and subjected to multivariate analysis were patient demographics, underlying disease, clinical data, and ventilator parameters and their association with hospital mortality. Nearly 10,843 patients underwent surgery during the study period, and the ARDS incidence rate was 0.76 % (83/10,843), with 64 patients (77 %, 64/83) receiving HFOV. No significant changes in systemic or central venous pressure were associated with initiation and maintenance of HFOV. The complications during HFOV included pneumothorax for 22 patients. The overall in-hospital mortality rate was 39 % (25/64). Multiple regression analyses indicated that pulmonary hypertension and recurrent respiratory tract infections (RRTIs) before surgery were independent predictors of in-hospital mortality. The findings show that HFOV is an effective and safe method for ventilating severe ARDS patients after corrective cardiac surgery. Pulmonary hypertension and RRTIs before surgery were risk factors for in-hospital mortality.     

经鼻同步间歇正压通气治疗早产儿呼吸暂停的临床研究

目的：比较经鼻同步间歇正压通气（NSIPPV）与经鼻持续气道正压通气（NCPAP）治疗早产儿呼吸暂停的疗效。方法：将2010年8月至2011年1月住院的80例呼吸暂停早产儿随机分为NSIPPV组与NCPAP组,每组40例,比较治疗前、治疗后2 h血气分析结果、上机时间、疗效和并发症。结果：治疗前两组血气分析结果的差异无统计学意义（P＞0.05）,治疗后2 h NSIPPV组的pH值、PaO2、PaCO2均明显优于NCPAP组（P＜0.05）;NSIPPV组上机时间（50±9 h）明显短于NCPAP组（91±11 h）,差异有统计学意义（P＜0.01）;两组治疗的总有效率（95% vs 85%）差异无统计学意义（P＞0.05）,但NSIPPV组3 d 内撤机的比例（23/40）明显高于NCPAP组（14/40）（P＜0.05）;两组并发症发生比率（22% vs 25%）差异无统计学意义（P＞0.05）。结论：NSIPPV治疗早产儿呼吸暂停比NCPAP更有优势。     

High frequency oscillation in newborn infants with respiratory failure

Objective: To report ventilation strategies, survival and complications in 39 outborn infants treated with high frequency oscillatory ventilation (HFOV).
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction.     

Ventilatory management of infant baboons with hyaline membrane disease: the use of high frequency ventilation

We tested the hypothesis that high frequency oscillatory ventilation (HFOV) would result in decreased pulmonary barotrauma in infants with hyaline membrane disease by comparing HFOV at 10 Hz to conventional positive pressure ventilation with continual distending airway pressure (PPV/PEEP) in premature baboons with hyaline membrane disease. Nineteen baboon fetuses were randomized to one of two treatment groups, delivered at 140 +/- 2 days, and, after stabilization and instrumentation of PPV/PEEP, placed in their respective ventilator group. Animals on conventional ventilation were managed by adjustment of tidal volume and frequency (to 1 Hz) to keep PaCO2 below 55 and by adjustment of the mean airway pressure. One of the "HFOV" group died of cardiovascular complications before going on HFOV and was eliminated from data analysis. The remaining HFOV baboons survived the 11-day experimental period without evidence of airleak. Six of the 11 prematures treated with PPV/PEEP developed pulmonary interstitial emphysema and/or pneumothorax and five of the animals died within 48 h. The intergroup differences in airleak were significant (p less than 0.05). Mean airway pressure (measured at the proximal airway) was higher initially with HFOV but then was lowered more rapidly than in the PPV/PEEP animals. The arterial to alveolar oxygen ratio rose and the FIO2 could be lowered more rapidly with HFOV than with conventional ventilation. These differences reached significance by 20 h. After 60 h there were no significant differences between HFOV and the PPV/PEEP survivors. HFOV resulted in more uniform saccular expansion, higher arterial to alveolar oxygen ratio, less oxygen exposure, and decreased acute barotrauma when compared to PPV/PEEP.(ABSTRACT TRUNCATED AT 250 WORDS)     

High-frequency oscillatory ventilation (HFOV) in the treatment of neonatal respiratory disturbances: case reports of two infants

The technique of high-frequency oscillatory ventilation (HFOV) was successfully used in a preterm infant with severe hyaline membrane disease and in a term neonate presenting with intrauterine pneumonia and associated severe pneumomediastinum. None of the infants could adequately be ventilated by conventional ventilation; both of them deteriorated owing to severe hypoxaemia and hypercapnia. In the preterm infant with HMD a rapid and progressive improvement of oxygenation had been observed immediately after the beginning of HFOV, and he was successfully weaned off the ventilator after 71 hours on HFOV. His recovery was uncomplicated and definitive. In the term neonate presenting with IUP and associated severe PM, an improvement in oxygenation was detected, whereas the retention of paCO2 remained unaltered. On leaving the MAP unchanged but doubling the flow rate, paCO2 and arterial pH also normalised. No sign of PM was seen on the X-ray picture 17.5 hours after the start of HFOV. This patient was weaned off the ventilator after 29 hours on HFOV and his recovery was also uncomplicated. It is believed that recovery of the PM was secondary to the low MAP and to the higher arterial pO2 levels, and that HFOV may also have a direct role in the treatment of preexisting air leaks and perhaps also in their prevention. In our patients HFOV resulted in a definitive recovery, while no improvement had occurred on using conventional ventilation. To determine the exact mechanism of action, the clear cut fields of indications and the possible side effects of HFOV, further investigations are needed.     

Tricuspid Annular Plane Systolic Excursion Does Not Correlate With Right Ventricular Ejection Fraction in Patients With Hypoplastic Left Heart Syndrome After Fontan Palliation

Tricuspid annular plane systolic excursion (TAPSE) reflects longitudinal myocardial shortening, the main component of right ventricular (RV) contraction in normal hearts. To date, TAPSE has not been extensively studied in patients with hypoplastic left heart syndrome (HLHS) and systemic RVs after Fontan palliation. This retrospective study investigated HLHS patients after Fontan with cardiac magnetic resonance (CMR) performed between 1 January 2010 and 1 August 2012 and transthoracic echocardiogram (TTE) performed within 6 months of CMR. The maximal apical displacement of the lateral tricuspid valve annulus was measured on CMR (using four-chamber cine images) and on TTE (using two-dimensional apical views). To create TTE–TAPSE z-scores, published reference data were used. Intra- and interobserver variability was tested with analysis of variance. Inter-technique agreement of TTE and CMR was tested with Bland–Altman analysis. In this study, 30 CMRs and TTEs from 29 patients were analyzed. The age at CMR was 14.1 ± 7.1 years, performed 11.9 ± 7.8 years after Fontan. For CMR–TAPSE, the intraclass correlation coefficients for inter- and intraobserver variability were 0.89 and 0.91, respectively. The TAPSE measurements were 0.57 ± 0.2 cm on CMR and 0.70 ± 0.2 cm on TTE (TTE–TAPSE z score, ?8.7 ± 1.0). The mean difference in TAPSE between CMR and TTE was ?0.13 cm [95 % confidence interval (CI) ?0.21 to ?0.05], with 95 % limits of agreement (?0.55 to 0.29 cm). The study showed no association between CMR–TAPSE and RVEF (R = 0.08; p = 0.67). In patients with HLHS after Fontan, TAPSE is reproducible on CMR and TTE, with good agreement between the two imaging methods. Diminished TAPSE suggests impaired longitudinal shortening in the systemic RV. However, TAPSE is not a surrogate for RVEF in this study population.     

Prophylactic high-frequency oscillatory ventilation in preterm infants

The role of high-frequency oscillatory ventilation (HFOV) for the treatment of respiratory disease in preterm infants remains uncertain. Several randomized trials, comparing HFOV and conventional ventilation (CV) have been performed and their results suggest that HFOV may reduce the incidence of chronic lung disease (CLD) in preterm infants. However, the trials have several limitations and it remains unclear whether HFOV might increase intracranial pathology in very prematurely born infants. UKOS, a large, UK-based, multicentre trial was conducted to establish conclusively the role of prophylactic HFOV for the prevention of CLD in infants born prior to 29 wk of gestational age.
Conclusion : There is still a need to fully evaluate prophylactic HFOV with particular emphasis on both short and long term respiratory and neurological outcomes.     

Effect of vibration on auditory organ systems in low-birth weight infants treated with high-frequency oscillatory ventilation: 5 year outcome

BACKGROUND: To determine the effects of vibration exposure caused by high-frequency oscillatory ventilation (HFOV) on the auditory organ systems in low-birth weight (LBW) infants. METHODS: Between 1989 and 1990, 30 LBW infants who received assisted ventilation with HFOV (n = 14) or conventional mechanical ventilation (CMV; n = 16) in the level III neonatal intensive care unit at Tokyo Metropolitan Ohtsuka Hospital were enrolled in this study. The effects of vibration exposure on the auditory system structures were investigated with auditory brainstem responses (ABR) at 37-41 weeks of postconceptional age and at 6, 12, 18 and 24 months of age until they passed and follow-up studies were performed at least until 5 years of age. RESULTS: All infants enrolled in the study survived at discharge and one (7.1%) infant in the HFOV group and two (12.5%) in the CMV group failed the initial ABR test, but there were no significant differences between the two groups. Auditory brainstem response abnormalities were still observed in one infant in the HFOV group at 6 months of age, but this child died at 9 months of age because of meningitis. In contrast, in the CMV group, one patient passed the ABR test at 6 months of age, but another remained abnormal at 5 years of age. One of three infants with ABR abnormalities at 6 months of age had neurologic sequelae at 5 years of age and one of 28 infants who passed the initial ABR test was detected with cerebral palsy. No patients with hearing loss were clinically detected at 5 years of age. CONCLUSIONS: The results of the serial ABR examinations and the 5 year follow-up studies suggest that vibration exposure caused by HFOV may not increase the adverse effects on the auditory system in LBW infants.     

Prophylactic high-frequency oscillatory ventilation in preterm infants

The role of high-frequency oscillatory ventilation (HFOV) for the treatment of respiratory disease in preterm infants remains uncertain. Several randomized trials, comparing HFOV and conventional ventilation (CV) have been performed and their results suggest that HFOV may reduce the incidence of chronic lung disease (CLD) in preterm infants. However, the trials have several limitations and it remains unclear whether HFOV might increase intracranial pathology in very prematurely born infants. UKOS, a large, UK-based, multicentre trial was conducted to establish conclusively the role of prophylactic HFOV for the prevention of CLD in infants born prior to 29 wk of gestational age. CONCLUSION: There is still a need to fully evaluate prophylactic HFOV with particular emphasis on both short and long term respiratory and neurological outcomes.     

Blood Pool Segmentation Results in Superior Virtual Cardiac Models than Myocardial Segmentation for 3D Printing

The method of cardiac magnetic resonance (CMR) three-dimensional (3D) image acquisition and post-processing which should be used to create optimal virtual models for 3D printing has not been studied systematically. Patients (n = 19) who had undergone CMR including both 3D balanced steady-state free precession (bSSFP) imaging and contrast-enhanced magnetic resonance angiography (MRA) were retrospectively identified. Post-processing for the creation of virtual 3D models involved using both myocardial (MS) and blood pool (BP) segmentation, resulting in four groups: Group 1—bSSFP/MS, Group 2—bSSFP/BP, Group 3—MRA/MS and Group 4—MRA/BP. The models created were assessed by two raters for overall quality (1—poor; 2—good; 3—excellent) and ability to identify predefined vessels (1–5: superior vena cava, inferior vena cava, main pulmonary artery, ascending aorta and at least one pulmonary vein). A total of 76 virtual models were created from 19 patient CMR datasets. The mean overall quality scores for Raters 1/2 were 1.63 ± 0.50/1.26 ± 0.45 for Group 1, 2.12 ± 0.50/2.26 ± 0.73 for Group 2, 1.74 ± 0.56/1.53 ± 0.61 for Group 3 and 2.26 ± 0.65/2.68 ± 0.48 for Group 4. The numbers of identified vessels for Raters 1/2 were 4.11 ± 1.32/4.05 ± 1.31 for Group 1, 4.90 ± 0.46/4.95 ± 0.23 for Group 2, 4.32 ± 1.00/4.47 ± 0.84 for Group 3 and 4.74 ± 0.56/4.63 ± 0.49 for Group 4. Models created using BP segmentation (Groups 2 and 4) received significantly higher ratings than those created using MS for both overall quality and number of vessels visualized (p < 0.05), regardless of the acquisition technique. There were no significant differences between Groups 1 and 3. The ratings for Raters 1 and 2 had good correlation for overall quality (ICC = 0.63) and excellent correlation for the total number of vessels visualized (ICC = 0.77). The intra-rater reliability was good for Rater A (ICC = 0.65). Three models were successfully printed on desktop 3D printers with good quality and accurate representation of the virtual 3D models. We recommend using BP segmentation with either MRA or bSSFP source datasets to create virtual 3D models for 3D printing. Desktop 3D printers can offer good quality printed models with accurate representation of anatomic detail.     

首选使用高频振荡通气治疗新生儿肺出血的临床效果分析

目的探讨首选高频振荡通气(HFOV)治疗新生儿肺出血的有效性及安全性。方法回顾性分析首选HFOV(首选组)和常频通气(CMV)治疗效果欠佳再换为HFOV解救性治疗(解救组)肺出血患儿26例的临床效果,比较两组患儿的氧合指数(OI)、肺出血时间、住院时间、上机时间、氧疗时间、合并症及转归变化。结果首选组治疗后1、6、12、24、48、72 h OI值明显低于解救组,差异有统计学意义(P0.05)。首选组呼吸机相关性肺炎(VAP)发生率明显低于解救组(P0.05),治愈率高于解救组(P0.05)。首选组气胸、颅内出血、消化道出血的发生率与解救组比较差异无统计学意义(P0.05)。存活患儿中,首选组在肺出血时间、住院时间、上机时间、氧疗时间上较解救组明显缩短(P0.05)。结论与解救组相比,首选HFOV较解救性使用HFOV能更好地改善肺出血患儿氧合功能,降低VAP的发生率,缩短病程,提高治愈率,且未增加不良反应的发生率。     

Assessment of neonatal ventilation during high-frequency oscillatory ventilation.

OBJECTIVE: To determine alterations in high-frequency oscillatory ventilation (HFOV) performance during clinical ventilator management. DESIGN: Clinical investigation. SETTING: Two level III intensive care nurseries in Wilmington, Delaware, and Philadelphia, Pennsylvania. PATIENTS: Thirty infants 1.49 +/- 1.01 kg with respiratory distress receiving HFOV. INTERVENTIONS: Due to the demonstrated benchtop load sensitivity of the HFOV (SensorMedics 3100), we hypothesized that measured tidal volume (Vt/kg) and high-frequency minute ventilation (HFMV) would vary inversely with respiratory rate adjustments and that ventilator performance will be affected with endotracheal tube (ETT) suctioning. Both Vt/kg and HFMV were recorded using a novel hot-wire anemometry technique at the time of ETT suctioning or changes in ventilator settings. MEASUREMENTS AND MAIN RESULTS: During HFOV it was found that Vt/kg = 2.52 +/- 0.68 mL/kg and HFMV = 69 +/- 45 ([mL/kg]2 x Hz); effective ventilation was observed in the range of HFMV = 29-113 ([mL/kg]2 x Hz). HFMV decreased with an increase in breathing frequency. Although there was a significant increase in the mean Vt/kg after suctioning events, there was no difference in Vt/kg or HFMV after disconnection of the ETT alone. There were significant alterations in HFOV performance as a result of clinical adjustments in respiratory rate and suctioning. In addition, we found that measured Vt during clinically effective HFOV is at least equivalent to expected deadspace. CONCLUSIONS: Measurement of tidal volume and HFMV may be clinically important in optimizing HFOV performance both during ETT suctioning and adjustments to breathing frequency.     

Novel Cardiac Magnetic Resonance Feature Tracking (CMR-FT) Analysis for Detection of Myocardial Fibrosis in Pediatric Hypertrophic Cardiomyopathy

Myocardial fibrosis is a risk factor for sudden cardiac death in hypertrophic cardiomyopathy (HCM) and is conventionally identified by cardiac magnetic resonance imaging (CMR) using late gadolinium enhancement (LGE). This study evaluates utility of a novel 16-segment CMR feature tracking (CMR-FT) technique for measuring left ventricular (LV) strain (S) and strain rate (SR) on non-contrast cine images to detect myocardial fibrosis in pediatric HCM. We hypothesized that CMR-FT-derived S and SR will accurately differentiate HCM patients with and without myocardial fibrosis. Consecutive children with HCM who underwent CMR with LGE at our institution from 2006 to 2014 were included. Global and regional longitudinal, radial and circumferential S and SR of the LV in 2D and 3D were obtained using a CMR-FT software. Comparisons were made between HCM patients with (+LGE) and without (?LGE) delayed enhancement. Of the 29 HCM patients (mean age 13.5 ± 6.1 years; 52 % males), 11 (40 %) patients (mean age 17.5 ± 8.4 years) had +LGE. Global longitudinal, circumferential and radial S and SR were lower in +LGE compared to ?LGE patients, in both 2D and 3D. Regional analysis revealed lower segmental S and SR in the septum with fibrosis compared to free wall without fibrosis. A global longitudinal S of ≤ ?12.8 had 91 % sensitivity and 89 % specificity for detection of LGE. In pediatric HCM patients with myocardial fibrosis, global LV longitudinal, circumferential and radial S and SR were reduced, specifically in areas of fibrosis. A global longitudinal S of ≤ ?12.8 detected patients with fibrosis with high degree of accuracy. This novel CMR-FT technique may be useful to identify myocardial fibrosis and risk-stratify pediatric HCM without use of contrast agents.     

Randomized trial of high-frequency oscillatory ventilation versus conventional ventilation: effect on systemic blood flow in very preterm infants

OBJECTIVE: Low superior vena cava (SVC) flow is common in very preterm infants in the first day and strongly associated with periventricular hemorrhage and disability. We examined the effect of high-frequency oscillatory ventilation (HFOV) compared with conventional ventilation (CV) on SVC flow and right ventricular output. METHODS: Forty-five infants <29 weeks were randomized before 1 hour of age to HFOV or CV. Echocardiography was performed on 43 infants at 3, 10, and 24 hours of age. Infants with low SVC flow (<50 mL/kg/min) or hypotension (mean blood pressure < or =20) were treated with volume and inotrope. RESULTS: Infants allocated to HFOV (n=23) and to CV (n=20) were well matched. There was a nonsignificant trend toward more infants on HFOV having SVC flow <50 mL/kg/min (48% vs 20%) and receiving volume and inotropes (61% vs 40%). There were no significant differences in mean SVC flow or right ventricular output at 3, 10, or 24 hours. Infants on HFOV had a significantly higher calculated upper body vascular resistance at 10 hours and mean blood pressure at 24 hours. CONCLUSIONS: There were no significant adverse effects of HFOV on systemic blood flow in very preterm infants during the first 24 hours of life.     

Impact of new treatments for respiratory failure on outcome of infants with congenital diaphragmatic hernia

Term and near-term newborn infants with congenital diaphragmatic hernia (CDH), symptomatic in the first 24 h of life or diagnosed antenatally, without other significant malformations were treated at our hospital with high-frequency oscillatory ventilation (HFOV) as a primary modality of ventilation and elective delay in surgical repair after a period of stabilisation. When unresponsive to HFOV, infants were treated with surfactant, inhaled nitric oxide (iNO) and extracorporeal membrane oxygenation (ECMO) to achieve pre-operative stabilisation. From October 1994 to August 1998, 28 newborn infants with CDH were managed with such treatment; mean birth weight was 3184 ± 535 g and gestational age 38.5 ± 1.85 weeks. Age at operation was 68 ± 35 h. In 9 cases, large diaphragmatic defects required the use of a prosthetic patch (Gore-tex). HFOV was used for primary ventilation in inborn patients (n = 16); outborn infants (n = 12) were placed on HFOV at admittance. A total of 15 patients (53%) were stabilised using only HFOV. Bovine surfactant was administered in 12 infants and 4 responded. iNO was used in eight infants and five responded. ECMO was used in three outborn patients and one survived. Overall, out of 28 infants, 25 survived (89%). Neurological examination (Amiel-Tison and Grenier) of 15 infants showed transient anomalies at 6 months in 40% of infants, while a normal neurological examination was present in all patients at 1 year. The development quotient (Griffiths scales) was within normal values in ten and mildly abnormal in two infants tested at 1 year. Conclusion Management based on early HFOV, eventually associated with surfactant, iNO and ECMO to achieve preoperative stabilisation, resulted in a good survival rate (89%) and good neurodevelopmental outcome at 1 year of age in infants with CDH. Received: 10 November 1998 and in revised form: 3 March 1999 / Accepted: 16 March 1999     

Endogenous pulmonary surfactant metabolism is not affected by mode of ventilation in premature infants with respiratory distress syndrome

OBJECTIVE: To determine if high frequency oscillatory ventilation (HFOV) decreases surfactant production in premature infants with respiratory distress syndrome (RDS). STUDY DESIGN: We randomized 19 infants <28 weeks of gestation to either HFOV (n = 8) or conventional ventilation (CV, n = 11) at 24 hours of life. After a 24-hour continuous infusion of uniformly labeled carbon 13 glucose (U-(13)C(6)) glucose, we measured (13)C enrichment in surfactant phosphatidylcholine (PC) in tracheal aspirate samples using gas chromatography/mass spectrometry. We calculated the fractional synthetic rate (FSR) of surfactant PC from labeled glucose and its half-life of clearance (T(1/2)). RESULTS: FSR did not differ between groups (4.7% +/- 2.7%/day CV vs 4.2% +/- 3.1%/day HFOV, P =.7). T(1/2) was 79 +/- 18 hours in the CV group and 76 +/- 23 hours in the HFOV group (P =.7). Neither degree of ventilatory support nor supplemental oxygen exposure correlated with surfactant metabolic indices. Three of 4 infants who died from RDS within the first month of life had a shorter T(1/2) than 14 of 15 infants who survived. CONCLUSION: Surfactant metabolism is similar in preterm infants ventilated with HFOV and CV. Shortened surfactant half-life may characterize a subset of preterm infants with lethal RDS.     

高频振荡通气在新生儿气胸治疗中的临床观察

目的：探讨高频振荡通气（HFOV）在新生儿气胸治疗中的疗效。方法：回顾性分析2007年1月至2011年6月接受HFOV治疗的23例新生儿气胸患儿的临床资料（HFOV组）,其中19例明确诊断后立即应用HFOV治疗,另4例因常频通气或持续气道正压通气治疗中出现气胸后改为HFOV。选取同期23例接受常频通气治疗的新生儿气胸患儿作为对照组。比较两组上机前、上机后1 h、12 h、24 h、48 h氧合指数（OI）、动脉/肺泡氧分压（a/APO2）以及上机时间、气胸吸收时间、合并症及转归。结果：两组呼吸机治疗后与上机前比较OI明显降低,a/APO2明显升高（P＜0.05）。HFOV组上机后1 h、12 h、24 h、48 h OI低于对照组,a/APO2高于对照组,（P＜0.05）。HFOV组上机时间、气胸吸收时间较对照组明显缩短（P＜0.05）。HFOV组治愈22例,对照组治愈21例。两组各出现呼吸机相关性肺炎1例,均在使用抗生素后治愈。结论：HFOV能更好地改善新生儿气胸患儿的氧合功能,缩短上机和气胸吸收时间,较常频通气治疗患儿并不增加不良反应的发生率。     

Intraoperative ventilation during thoracoscopic repair of neonatal congenital diaphragmatic hernia

Purpose

To evaluate the optimal ventilation mode during thoracoscopic repair (TR) of neonatal congenital diaphragmatic hernia (CDH), we compared high-frequency oscillatory ventilation (HFOV) with conventional mechanical ventilation (CMV).

Methods

Twenty-three neonatal CDH cases who underwent TR without intraoperative inhalation of nitric oxide at our institution between 2007 and 2016 were reviewed. Patients were initially ventilated with HFOV, which was converted to CMV if the HFOV settings were decreased to FiO₂ <0.4, stroke volume <4 mL/kg and mean airway pressure <12 cmH₂O. Arterial blood gases in the perioperative period were compared between HFOV and CMV.

Results

Seventeen patients were ventilated with HFOV (group I), and six patients were ventilated with CMV (group II). Preoperative PaCO₂ was significantly higher and pH was significantly lower in group I compared with group II. In both groups I and II, intraoperative PaCO₂ increased significantly and pH decreased significantly compared with preoperation. Although intraoperative PaCO₂ and pH were not different between the groups, group II showed greater worsening of intraoperative PaCO₂ and pH as compared to their respective preoperative values.

Conclusions

HFOV seems to prevent deterioration of hypercapnia and acidosis to a greater extent than CMV during TR in neonatal cases of CDH, although patients can also be ventilated with CMV.