High-Frequency Jet Ventilation Versus Spontaneous Respiration for Percutaneous Cryoablation of Lung Tumors: Comparison of Adverse Events and Procedural Efficiency.

BACKGROUND. High-frequency jet ventilation (HFJV) facilitates accurate probe placement in percutaneous ablation of lung tumors but may increase risk for adverse events, including systemic air embolism. OBJECTIVE. The purpose of this study was to compare major adverse events and procedural efficiency of percutaneous lung ablation with HFJV under general anesthesia to spontaneous respiration (SR) under moderate sedation. METHODS. This retrospective study included consecutive adults who underwent CT-guided percutaneous cryoablation of one or more lung tumors with HFJV or SR between January 1, 2017, and May 31, 2023. We compared major adverse events (Common Terminology Criteria for Adverse Events grade ≥ 3) within 30 days postprocedure and hospital length of stay (HLOS) of 2 days or more using logistic regression analysis. We compared procedure time, room time, CT guidance acquisition time, CT guidance radiation dose, total radiation dose, and pneumothorax using generalized estimating equations. RESULTS. Overall, 139 patients (85 women, 54 men; median age, 68 years) with 310 lung tumors (82% metastases) underwent 208 cryoablations (HFJV, n = 129; SR, n = 79). HFJV showed greater rates than SR for the treatment of multiple tumors per session (43% vs 19%, respectively; p = .02) and tumors in a nonperipheral location (48% vs 24%, p < .001). Major adverse event rate was 8% for HFJV and 5% for SR (p = .46). No systemic air embolism occurred. HLOS was 2 days or more in 17% of sessions and did not differ significantly between HFJV and SR (p = .64), including after adjusting for probe number per session, chronic obstructive pulmonary disease, and operator experience (p = .53). Ventilation modalities showed no significant difference in procedure time, CT guidance acquisition time, CT guidance radiation dose, or total radiation dose (all p > .05). Room time was longer for HFJV than SR (median, 154 vs 127 minutes, p < .001). For HFJV, the median anesthesia time was 136 minutes. Ventilation modalities did not differ in the frequencies of pneumothorax or pneumothorax requiring chest tube placement (both p > .05). CONCLUSION. HFJV appears to be as safe as SR but had longer room times. HFJV can be used in complex cases without significantly impacting HLOS of 2 days or more, procedure time, or radiation exposure. CLINICAL IMPACT. Selection of the ventilation modality during percutaneous lung ablation should be based on patient characteristics and anticipated procedural requirements as well as operator preference.

Evaluation of lung volumes and gas exchange in surfactant-deficient rabbits between variable and fixed servo pressures during high-frequency jet ventilation.

OBJECTIVE: To investigate a novel servo pressure (SP) setting during high-frequency jet ventilation (HFJV) for a lung protective strategy in a neonatal model of acute respiratory distress. STUDY DESIGN: Comparison of efficacy between variable (standard) and fixed SP settings in a randomized animal study using rabbits (n = 10, mean weight = 1.80 kg) with surfactant deficiency by repeated lung lavages. RESULTS: Rabbits in the fixed SP group had greater peak inspiratory pressure, SP, minute volume, pH, and PaO2, and lower PaCO2 after lung lavage than the variable SP group. Lung volume monitoring with electrical impedance tomography showed that fixed SP reduced the decline of the global lung tidal variation at 30 min after lung lavage (-17.4% from baseline before lavage) compared to variable SP (-44.9%). CONCLUSION: HFJV with fixed SP significantly improved gas exchange and lung volumes compared to variable SP. Applying a fixed SP may have important clinical implications for patients receiving HFJV.

Recovery and safety with prolonged high-frequency jet ventilation for catheter ablation of atrial fibrillation: A hospital registry study from a New England healthcare network.

STUDY OBJECTIVE: To investigate post-procedural recovery as well as peri-procedural respiratory and hemodynamic safety parameters with prolonged use of high-frequency jet ventilation (HFJV) versus conventional ventilation in patients undergoing catheter ablation for atrial fibrillation. DESIGN: Hospital registry study. SETTING: Tertiary academic teaching hospital in New England. PATIENTS: 1822 patients aged 18 years and older undergoing catheter ablation between January 2013 and June 2020. INTERVENTIONS: HFJV versus conventional mechanical ventilation. MEASUREMENTS: The primary outcome was post-anesthesia care unit (PACU) length of stay. In secondary analyses we assessed the effect of HFJV on intra-procedural hypoxemia, defined as the occurrence of peripheral hemoglobin oxygen saturation (SpO2) <90%, post-procedural respiratory complications (PRC) as well as intra-procedural hypocarbia and hypotension. Multivariable negative binomial and logistic regression analyses, adjusted for patient and procedural characteristics, were applied. MAIN RESULTS: 1157 patients (63%) received HFJV for a median (interquartile range [IQR]) duration of 307 (253-360) minutes. The median (IQR) length of stay in the PACU was 244 (172-370) minutes in patients who underwent ablation with conventional mechanical ventilation and 226 (163-361) minutes in patients receiving HFJV. In adjusted analyses, patients undergoing HFJV had a longer PACU length of stay (adjusted absolute difference: 37.7 min; 95% confidence interval [CI] 9.7-65.8; p = 0.008). There was a higher risk of intra-procedural hypocarbia (adjusted odds ratio [ORadj] 5.90; 95%CI 2.63-13.23; p < 0.001) and hypotension (ORadj 1.88; 95%CI 1.31-2.72; p = 0.001) in patients undergoing HFJV. No association was found between the use of HFJV and intra-procedural hypoxemia or PRC (p = 0.51, and p = 0.97, respectively). CONCLUSION: After confounder adjustment, HFJV for catheter ablation procedures for treatment of atrial fibrillation was associated with a longer length of stay in the PACU. It was further associated with an increased risk of intra-procedural abnormalities including abnormal carbon dioxide homeostasis, as well as intra-procedural arterial hypotension.

The Impact of Tracheal Stenosis on Distal Airway Pressure with Jet Ventilation.

OBJECTIVE: This study investigates the effects of tracheal stenosis on distal airway pressure during low-frequency jet ventilation (LFJV) in tracheal stenosis resection procedures, focusing on variables like stenosis size, depth, scope type, and inlet pressure. METHODS: A 3D-printed human airway model was employed, featuring inserted tracheal stenoses of varied sizes and depths. Distal airway pressure was measured with 16 pressure transducers, and data were processed via MATLAB. The study varied stenosis size, depth, scope type, and inlet pressure during five sequential jet bursts under LFJV. RESULTS: Using a subglottiscope resulted in significantly reduced distal airway pressure compared to a laryngoscope. Interestingly, neither stenosis size nor depth significantly influenced distal airway pressure. However, increased distance between the scope and stenosis raised normalized pressure. A linear rise in normalized distal airway pressure was noted with increased inlet pressure, regardless of stenosis dimensions. CONCLUSION: In this model, scope type and inlet pressure were noted to be significant determinants of distal airway pressure, while stenosis size and depth were not. The distance between the scope and the stenosis did influence distal pressures. These findings may have clinical implications for managing airway pressures in patients undergoing LFJV, potentially reducing the risk of ventilator-induced lung injury. LEVEL OF EVIDENCE: NA (Basic Research) Laryngoscope, 134:2300-2305, 2024.

Application and Technical Principles of Catheter High-Frequency Jet Ventilation.

The aim of this publication is to analyze the topic of high-frequency jet ventilation (HFJV), namely catheter HFJV (C-HFJV), from a mathematical-physical as well as a clinical point of view. There are known issues with applying anesthesia and artificial lung ventilation (ALV) during surgical procedures in the upper airways, e.g., during bronchoscopy or tracheostomy. The principles, advantages, and disadvantages of HFJV are discussed in context with basic physical principles to clarify the proper use of this method. The basic technical principles of catheter construction, as well as its functional properties from a biophysical point of view, are introduced. Also, the placement of the catheter in the airways, the set-up of the HFJV ventilator, and the indications as well as the risks and contraindications of the use of C-HFJV are analyzed. This leads to the explanation of potentially optimal techniques for C-HFJV applications. In this article, we present the positive effects of C-HFJV even with complications such as bacterial or viral pneumonia, including COVID-19. In conclusion, we offer recommendations for clinical practice obtained from a literature review and from our rich clinical experience.

The Tritube: Facilitating Upper Airway Surgery With an Ultrathin Cuffed Airway Device.

The Tritube is a narrow-bore cuffed tracheal tube (outer diameter 4.4 mm and inner diameter ~2.4 mm) that permits effective alveolar gas exchange using flow-controlled ventilation. Constant gas flow delivers physiological minute volumes, within preset pressure limits, and applies suction to the airway during expiration. The technique has attracted interest for laryngotracheal microsurgery as it provides superior surgical exposure and avoids many of the complications associated with high-frequency jet ventilation. Cuff inflation protects the lower airway and produces a motionless operating field. We describe the structure of the device, discuss its benefits, and suggest how it should be used clinically.

Quantitative assessment of atelectasis formation under high frequency jet ventilation during liver tumour ablation-A computer tomography study.

BACKGROUND: High frequency jet ventilation (HFJV) can be used to minimise sub-diaphragmal organ displacements. Treated patients are in a supine position, under general anaesthesia and fully muscle relaxed. These are factors that are known to contribute to the formation of atelectasis. The HFJV-catheter is inserted freely inside the endotracheal tube and the system is therefore open to atmospheric pressure. AIM: The aim of this study was to assess the formation of atelectasis over time during HFJV in patients undergoing liver tumour ablation under general anaesthesia. METHOD: In this observational study twenty-five patients were studied. Repeated computed tomography (CT) scans were taken at the start of HFJV and every 15 minutes thereafter up until 45 minutes. From the CT images, four lung compartments were defined: hyperinflated, normoinflated, poorly inflated and atelectatic areas. The extension of each lung compartment was expressed as a percentage of the total lung area. RESULT: Atelectasis at 30 minutes, 7.9% (SD 3.5, p = 0.002) and at 45 minutes 8,1% (SD 5.2, p = 0.024), was significantly higher compared to baseline 5.6% (SD 2.5). The amount of normoinflated lung volumes were unchanged over the period studied. Only a few minor perioperative respiratory adverse events were noted. CONCLUSION: Atelectasis during HFJV in stereotactic liver tumour ablation increased over the first 45 minutes but tended to stabilise with no impact on normoinflated lung volume. Using HFJV during stereotactic liver ablation is safe regarding formation of atelectasis.

High frequency jet ventilation for congenital diaphragmatic hernia.

BACKGROUND: The optimal role of high frequency jet ventilation (HFJV) in lung protective stabilization of congenital diaphragmatic hernia (CDH) remains uncertain. We aimed to describe our center's experience with HFJV as both a rescue (following failed stabilization with CMV) and primary ventilation mode in the management of CDH. METHODS: Liveborn CDH patients treated from 2013 to 2021 in a single institution were reviewed. We compared 3 groups based on their primary and last ventilation mode prior to surgery: CMV (Group 1); HFJV (Group 2); and CMV/HFJV (Group 3). Outcomes included a composite primary outcome (≥1 of mortality, need for ECMO or need for supplemental O2 at discharge), total invasive ventilation days and development of pneumothorax. A descriptive analysis including univariate group comparisons was performed. Multivariate logistic regression models investigating the relationship between mode of ventilation and the primary outcome adjusted by potentially confounding covariates were constructed. RESULTS: 56 patients (32 Group 1, 18 Group 2, 6 Group 3) were analyzed. Group 2 and 3 patients had more severe disease based on liver position, SNAP-II score, pulmonary hypertension severity, need for inotropic support, CDHSG defect size and need for patch repair. There were no group differences in survival, need for ECMO, or pneumothorax occurrence, although infants receiving HFJV required longer invasive ventilation and had a greater need for O2 at discharge. Multivariate logistic regression revealed no associations between mode of ventilation and outcome. CONCLUSIONS: HFJV appears effective, both for CMV rescue and as a primary ventilation strategy in high risk CDH. LEVEL OF EVIDENCE: Level IV.

Safety of High-Frequency Jet Ventilation During Image-Guided Thermal Ablation Procedures.

RATIONALE AND OBJECTIVE: Percutaneous thermal ablative technique is a common radiological procedure for malignant lesions treatment. Controlled assisted ventilation during general anesthesia is the usual mode of ventilation, but high-frequency jet ventilation (HFJV) can be a helpful alternative for the operator. The objective was to evaluate the safety of HFJV during thermal ablation procedures. MATERIALS AND METHODS: This monocentric prospective analysis included adult patients undergoing percutaneous thermal ablation procedures for abdominal tumor performed under HFJV. Procedures with a transpulmonary path were excluded. The primary outcome was the incidence of respiratory complications. Secondary outcomes included gas exchange modifications (hypercapnia, hypoxemia, pulmonary atelectasis) and the incidence of barotrauma. RESULTS: Sixty patients were included during the study period. The mean duration time was 88 min. All procedures went according to the protocol and there was no respiratory complication. There was no barotrauma event. Three patients had an exhaled capnia above 45 mmHg at the end of the procedure which normalized within 10 min of conventional ventilation. CONCLUSION: HFJV during thermal ablation procedures is safe regarding gas exchange and barotrauma. This technique could be an interesting alternative to conventional ventilation during image-guided thermal ablation procedures. Clinical Trials database This study was registered in Clinical Trials database (NCT04209608).

Clinical study of multifunctional laryngeal mask in airway interventional therapy.

OBJECTIVE: This study is conducted to evaluate the efficacy and safety of using multifunctional intubation laryngeal masks with normal frequency jet ventilation in airway interventional therapy. METHODS: A total of 200 patients receiving airway interventional therapy were enrolled in this retrospective study and were divided into 2 groups (group M and group P) by doctors in our hospital to compare the effect of different laryngeal masks. Group M used common laryngeal masks and an anesthesia machine for positive pressure ventilation while group P took multifunctional intubation laryngeal masks and used a jet ventilator for normal frequency jet ventilation. The patients' mean arterial pressure, heart rate, arterial oxygen partial pressure (PaO2) and arterial carbon dioxide partial pressure (PaCO2), and the operation time, recovery score and the patients' and doctors' satisfaction levels were compared between the 2 groups. RESULTS: Both groups were hemodynamically stable, and their PaO2 levels were significantly higher before the operation than that during and after the operation (P < .05). Compared with group M, the PaCO2 level of group P was more stable both during and after the operation, and this difference was statistically significant (P < .05). There was no statistically significant difference in terms of the 2 group's operating time, recovery score, and patients' satisfaction levels (P > .05). However, the satisfaction levels of doctors in group P were higher than that in group M, and this difference was statistically significant (P < .05). CONCLUSION: As statistics show, the intraoperative hemodynamics and PaO2 and PaCO2 levels were stable, and patients, surgeons and anesthesia operators were satisfied. Therefore, it is feasible to apply multifunctional intubation laryngeal masks with normal frequency jet ventilation in airway interventional therapy and it is a safe and ideal way to ensure ventilation.

In-Circuit High-Frequency Jet Ventilation for Radiological Tumor Ablation: A Case Series.

High-frequency jet ventilation (HFJV) can reduce organ movement that otherwise complicates percutaneous image-guided ablation (IGA) procedures. This study describes feasibility and safety of the technique in routine use. We describe our method for the use of HFJV and present 169 consecutive cases, including IGA of tumors of the lung, liver, kidney, and pancreas. Intended oncological treatment was delivered in all cases and HFJV used for the duration of treatment in all except one case. We describe the characteristics of patients, procedures, and adverse events. It is feasible to use HFJV as the routine standard of care for IGA.

Parameters of high-frequency jet ventilation using a mechanical lung model.

High frequency jet ventilationis a mechanical lung ventilation method which uses a relatively high flow usually through an open system. This work examined the effect of high-frequency jet ventilation on respiratory parameters of an intubated patient simulated using a high-frequency jet ventilator attached to a ventilation monitor for measurements of ventilation parameters. The series of experiments altered specific parameters each time (respiratory rate, inspiratory-expiratory (I:E) ratio, and inspiratory pressure), under different lung compliances. A reduction of minute ventilation was observed alongside a rise in respiratory rate, with low airway pressures over the entire range of lung compliances. In addition, an I:E ratio of 2:1 to 1:1; and the tidal and minute volumes were directly related to the inspiratory pressure over all compliance settings. To conclude, the respiratory mechanics in high-frequency jet ventilation are very different from those of conventional rate ventilation in a lung model. Further studies on patients and/or a biological model are needed to investigate pCO2 and end-tidal carbon-dioxide during high-frequency jet ventilation.

Feasibility, Safety, and Short-Term Outcomes of Transcatheter Patent Ductus Arteriosus Closure in Premature Infants on High-Frequency Jet Ventilation.

Background Prolonged exposure to a hemodynamically significant patent ductus arteriosus (PDA) is associated with major morbidity, particularly in infants born at <27 weeks' gestation. High-frequency jet ventilation (HFJV) is a standard of care at our center. There are no data about transcatheter PDA closure while on HFJV. The aim of this study was to assess the feasibility, safety, and outcomes of HFJV during transcatheter PDA closure. Methods and Results This is a retrospective cohort study of premature infants undergoing transcatheter device closure on HFJV. The primary outcome was successful device placement. Secondary outcomes included procedure time, fluoroscopy time and dose, time off unit, device complications, need for escalation in respiratory support, and 7-day survival. Subgroup comparative evaluation of patients managed with HFJV versus a small cohort of patients managed with conventional mechanical ventilation was performed. Thirty-eight patients were included in the study. Median age and median weight at PDA device closure for the HFJV cohort were 32 days (interquartile range, 25.25-42.0 days) and 1115 g (interquartile range, 885-1310 g), respectively. There was successful device placement in 100% of patients. There were no device complications noted. The time off unit and the procedure time were not significantly different between the HFJV group and the conventional ventilation group. Infants managed by HFJV had shorter median fluoroscopy times (4.5 versus 6.1 minutes; P<0.05) and no increased risk of adverse respiratory outcomes. Conclusions Transcatheter PDA closure in premature infants on HFJV is a safe and effective approach that does not compromise device placement success rate and does not lead to secondary complications.

Is HFJV a better alternative ventilation technique for percutaneous dilatational tracheostomy? A randomized trial.

BACKGROUND: High-frequency jet ventilation (HFJV) has been used for the treatment of tracheal lesions, airway surgery, and treatment of secondary lesions after tracheostomy for many years however, reports on the use of HFJV during percutaneous dilatational tracheostomy (PDT) are limited. This study compares the use of traditional method, ventilation with laryngeal mask airway (LMA), and HFJV through endotracheal tube (ETT) with respect to the duration of PDT procedure and complications. METHODS: Seventy-five patients were randomized into one of the three groups with computer-generated random numbers: Group ETT (N.=25), group LMA (N.=25), and group HFJV (n=25). Demographic data, duration of PDT, complications such as ETT cuff puncture and tube transaction, accidental extubation, difficult cannula insertion, bleeding, desaturation during the procedure, arterial blood gases immediately before and after the procedure have been recorded. RESULTS: Mean time for successful PDT in group ETT was 5.9±1.35 minutes, in group LMA 4.96±0.78 minutes, and 3.88±0.78 minutes in group HFJV. PDT duration was shorter in the LMA group than in the ETT group (P<0.05). In the HFJV group, the PDT duration was shorter than the LMA group (P<0.05) and the ETT group (P<0.001). In terms of the total number of complications, significantly fewer complications were observed in the HFJV group compared with group ETT and group LMA. CONCLUSIONS: HFJV may be a more effective alternative method for airway management during PDT, facilitating and reducing the duration of the intervention.

Very low tidal volume, high-frequency ventilation in atrial fibrillation ablation: a systematic review.

BACKGROUND: Ventilation strategies in atrial fibrillation ablation affect procedure outcomes by influencing catheter stability. Studies have highlighted favorable atrial fibrillation (AF) ablation outcomes with the use of high-frequency jet ventilation (HFJV) which has been shown to improve lesion durability, energy delivery, and tissue contact. However, this mode of ventilation is not readily available. In this systematic review, we highlight the available data on the use of very low tidal volume, high-frequency ventilation using standard ventilators that aim to provide settings similar to HFJV during AF ablations. METHODS: Using a combination of search terms in databases and manual searches in bibliographies of identified articles, we reviewed all published data reported in the English language on the use of very low tidal volume with high-frequency ventilation during atrial fibrillation ablation. RESULTS: A total of 4 manuscripts were identified; 3 cohort studies and 1 case report. The utilization of standard ventilators with a high-frequency, very low tidal volume ventilation strategy appears to closely mimic the catheter stability benefits that HFJV ventilators provide. Across the 3 cohort identified studies, the use of this ventilation strategy was associated with improved catheter stability, tissue contact, and a decrease in radiofrequency time. No increased risk was identified compared to standard ventilation. CONCLUSION: With a purpose of limiting thoracic excursion and cardiac movement, limited and sparse studies have shown improved outcomes with a very low tidal volume, high-frequency ventilation strategy. Additional studies are needed to solidify this easily accessible and widely available mode of ventilation.

First intention high-frequency jet ventilation for periviable infants.

PURPOSE OF REVIEW: Ventilation of periviable infants born at 22-23 weeks gestation remains a challenge in neonatology. This review highlights the evidence surrounding the use of first intention high-frequency jet ventilation (HFJV) in infants born near the limits of viability with a review of pulmonary fetal development and a focused overview of HFJV strategies including an in-depth analysis of the management strategies used in the initial randomized trials. RECENT FINDINGS: A paucity of recent trials exists, with no randomized control trials assessing the use of first intention HFJV performed in the last 25 years. A retrospective observational cohort trial of the use of HFJV for infants born at less than 750 g has been recently published demonstrating the efficacy of HFJV for this population even with 2.0-mm endotracheal tubes. SUMMARY: The lack of recent randomized trials contributes to the controversy surrounding the use of first intention HFJV. Although new research is needed in the area, this review includes the ventilation strategy of an experienced center with a focus on the use of first intention HFJV for the care of premature infants born less than 24 weeks gestation.