Comparison of superimposed high-frequency jet ventilation with conventional jet ventilation for laryngeal surgery

Effects of unilateral superimposed high-frequency jet ventilation on porcine hemodynamics and gas exchange during one-lung flooding

BACKGROUND

Superimposed high-frequency jet ventilation (SHFJV) is suitable for respiratory motion reduction and essential for effective lung tumor ablation. Fluid filling of the target lung wing one-lung flooding (OLF) is necessary for therapeutic ultrasound applications. However, whether unilateral SHFJV allows adequate hemodynamics and gas exchange is unclear.

AIM

To compared SHFJV with pressure-controlled ventilation (PCV) during OLF by assessing hemodynamics and gas exchange in different animal positions.

METHODS

SHFJV or PCV was used alternatingly to ventilate the non-flooded lungs of the 12 anesthetized pigs during OLF. The animal positions were changed from left lateral position to supine position (SP) to right lateral position (RLP) every 30 min. In each position, ventilation was maintained for 15 min in both modalities. Hemodynamic variables and arterial blood gas levels were repeatedly measured.

RESULTS

Unilateral SHFJV led to lower carbon dioxide removal than PCV without abnormally elevated carbon dioxide levels. SHFJV slightly decreased oxygenation in SP and RLP compared with PCV; the lowest values of PaO2 and PaO2/FiO2 ratio were found in SP [13.0; interquartile range (IQR): 12.6-5.6 and 32.5 (IQR: 31.5-38.9) kPa]. Conversely, during SHFJV, the shunt fraction was higher in all animal positions (highest in the RLP: 0.30).

CONCLUSION

In porcine model, unilateral SHFJV may provide adequate ventilation in different animal positions during OLF. Lower oxygenation and CO2 removal rates compared to PCV did not lead to hypoxia or hypercapnia. SHFJV can be safely used for lung tumor ablation to minimize ventilation-induced lung motion.

High-flow Nasal Cannula versus Conventional Ventilation in Laryngeal Surgery: A Systematic Review and Meta-analysis

High-flow nasal cannula (HFNC) is an emerging option for maintaining oxygenation in patients undergoing laryngeal surgery, as an alternative to traditional tracheal ventilation and jet ventilation (JV). However, the data on its safety and efficacy is sparse. This study aims to aggregate the current data and compares the use of HFNC with tracheal intubation and jet ventilation in adult patients undergoing laryngeal surgery. We searched PubMed, MEDLINE (Medical Literature Analysis and Retrieval System Online, or MEDLARS Online), Embase (Excerpta Medica Database), Google Scholar, Cochrane Library, and Web of Science. Both observational studies and prospective comparative studies were included. Risk of bias was appraised with the Cochrane Collaboration Risk of Bias in Non-Randomized Studies - of Interventions (ROBINS-I) or RoB2 tools and the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for case series. Data were extracted and tabulated as a systematic review. Summary statistics were performed. Meta-analyses and trial sequential analyses of the comparative studies were performed. Forty-three studies (14 HFNC, 22 JV, and seven comparative studies) with 8064 patients were included. In the meta-analysis of comparative studies, the duration of surgery was significantly reduced in the THRIVE (Transnasal Humidified Rapid-Insufflation Ventilatory Exchange) group, but the number of desaturations, need for rescue intervention, and peak end-tidal CO₂ were significantly increased compared to the conventional ventilation group. The evidence was of moderate certainty and there was no evidence of publication bias. In conclusion, HFNC may be as effective as tracheal intubation in oxygenation during laryngeal surgery in selected adult patients and reduces the duration of surgery but conventional ventilation with tracheal intubation may be safer. The safety of JV was comparable to HFNC.

A multi-centre prospective random control study of superimposed high-frequency jet ventilation and conventional jet ventilation for interventional bronchoscopy

Introduction: Superimposed high-frequency jet ventilation (SHFJV) is a new type of jet ventilation that simultaneously uses high- and low-frequency types of jet ventilation. We compared SHFJV with the conventional high-frequency jet ventilation (CHFJV) in interventional bronchoscopy in terms of safety and effectiveness. Methods: A multi-centre prospective random single-blind clinical trial was conducted by three interventional bronchoscopy centres. Patients who underwent diagnostic or therapeutic bronchoscopy under general anaesthesia were admitted and divided into two groups: SHFJV group (trial group) and CHFJV group (control group). PaO2 and PaCO2 were recorded before anaesthesia and during and after the procedure. SpO2 and etCO2 were recorded every 10 min throughout the procedure. Patients were observed until 24 h post-bronchoscopy. Results: Sixty patients were included in the study. Twenty-nine were in the trial group, and 31 were in the control group. Both groups had no significant differences in demographic data. In the control group, the PaO2 measured in the operation was higher than that in the trial group (p = 0.023). The values of etCO2 in the control group were more dispersed than those of the trial group. When the procedure time was over 90 minutes, the etCO2 in the control group significantly increased (p = 0.01), while the etCO2 in trial group remained stable (p = 0.594). There were more patients with PaCO2 ≥ 50 mmHg during the procedure in the control group than in the trial group (p = 0.042). Conclusion: SHFJV is effective and safe in interventional bronchoscopy. It may provide more effective and stabilised ventilation than CHFJV in cases with long procedure times.

Low Pressure Low Frequency Jet Ventilation: Techniques, Safety and Complications

OBJECTIVE

Manual jet ventilation is a specialized oxygenation and ventilation technique that is not available in all facilities due to lack of technical familiarity and fear of complications. The objective is to review our center's 15 year experience with low pressure low frequency jet ventilation (LPLFJV).

METHODS

Retrospective review of procedures utilizing LPLFJV from 2005 to 2019 were performed collecting patient demographic, surgery type and complications. Fisher exact test, Chi square, and t-test were used to determine statistical significance.

RESULTS

Four hundred fifty-seven patients underwent a total of 891 microlaryngeal surgeries-279 cases for voice disorders, 179 for lesions, and 433 for airway stenosis. The peak jet pressure for all cases did not exceed 20 psi and average peak pressure for the last 100 procedures in this case series was 14.9 ± 4.6 psi. The average lowest oxygen saturation for all cases was 95% ± 0.6%. Brief intubation was required in 154 cases (17%). Surgical duration was significantly longer for cases requiring intubation P < .001. The need for intubation was not associated with smoking or cardiopulmonary disease, but was strongly associated with body mass index (BMI). Intubation rates were 7% for normal weight (BMI < 25, N = 216), 13% for overweight (BMI 25-30, N = 282), 24% for obese (BMI 30-40, N = 342), and 37% for morbidly obese (BMI > 40, N = 52) patients. Three patients developed respiratory distress in the recovery unit and 2 patients required intubation.

CONCLUSION

LPLFJV assisted by intermittent endotracheal intubation is an exceedingly safe and effective intraoperative oxygenation and ventilationmodality for a broad variety of laryngeal procedure.

Supraglottic jet oxygenation and ventilation assisted fiberoptic intubation in a paralyzed patient with morbid obesity and obstructive sleep apnea: a case report

Background

Hypoxia is a major concern and cause of morbidity or mortality during tracheal intubation after anesthesia induction in a pathological obese patient with obstructive sleep apnea (OSA). We introduce a case using Supraglottic jet oxygenation and ventilation (SJOV) to promote oxygenation/ventilation during fiberoptic intubation in a paralyzed patient with morbid obesity and OSA.

Case presentation

A 46-year-old man weighting 176 kg with BMI 53.7 kg/m2 was scheduled for gastric volume reduction surgery to reduce body weight under general anesthesia. SpO2 decreased during induction, and two hand pressured mask ventilation partial failed. We then placed WEI Nasal Jet Tube (WNJ) in the patient’s right nostril to provide SJOV. Then fiberoptic bronchoscopy guided endotracheal intubation was performed via mouth approach, and vital signs were stable. The operation was successfully completed after 3 h. Patient recovered smoothly in hospital for 8 days and did not have any recall inside the operating room.

Conclusion

SJOV via WNJ could effectively maintain adequate oxygenation/ventilation during long time fiberoptic intubation in an apnea patient with morbid obesity and OSA after partial failure of two hand pressured mask ventilation, without obvious complications. This may provide a new effective approach for difficult airway management in these patients.

A New and Safe Mode of Ventilation for Interventional Pulmonary Medicine: The Ease of Nasal Superimposed High Frequency Jet Ventilation

We use pulmonary interventional procedures for the diagnosis of pulmonary diseases either for benign or malignant lesions. Flexible bronchoscopy with or without radial endobronchial ultrasound, convex-probe endobronchial ultrasound and electromagnetic navigation are procedures performed in centers with experience in diagnostic pulmonary medicine. The method of sedation and ventilation is very important in order to avoid or handle with success complications. Proper respiration during pulmonary (or other interventional) procedures is a key factor. Apart from the proper sedation method we have to choose the proper ventilation method which decides respiratory movement. Superimposed high-frequency jet ventilation (SHFJV) is supposed to be safe and effective in clinical practice. Although this perception is commonly accepted, there is no study proving its safety on the basic of reliable data. We analyzed the data of 100 patients in different interventional settings (bronchoscopy with or without navigational approach, left atrial appendage closure (LAAC) or intracardiac catheterization) using nasal SHFJV. Mainly analyzed were capillary ABG-Data at the beginning and end of the intervention under sedation. The aim was to analyze if a risk scenario for the patient by using the nasal SHFJV can be derived by measuring the changes of pCO2, pO2, cBase Excess, cHCO3 and PH. Due to our data we conclude that this method of ventilation can be easily and safely used in interventional medicine for patients with all kind of comorbidities such as; chronic respiratory disease, lung cancer, interstitial lung disease, structural heart disease and heart failure.

A new mode of ventilation for interventional pulmonology. A case with EBUS-TBNA and debulking

Lung cancer is still underdiagnosed mainly due to lack of symptoms. Most patients are diagnosed in a late stage where unfortunately only systematic therapy can be applied. Fortunately in the last five years several novel therapies and combinations have emerged. However; in certain situations local therapeutics modalities have to be applied in order to solve emergency problems as in the case that we will present. Convex-EBUS probe was used along with a novel method of ventilation which keeps PCO₂ concentration satisfyingly low.

Anaesthetic management of acute airway obstruction

The acutely obstructed airway is a medical emergency that can potentially result in serious morbidity and mortality. Apart from the latest advancements in anaesthetic techniques, equipment and drugs, publications relevant to our topic, including the United Kingdom's 4th National Audit Project on major airway complications in 2011 and the updated American Society of Anesthesiologists' difficult airway algorithm of 2013, have recently been published. The former contained many reports of adverse events associated with the management of acute airway obstruction. By analysing the data and concepts from these two publications, this review article provides an update on management techniques for the acutely obstructed airway. We discuss the principles and factors relevant to the decision-making process in formulating a logical management plan.

Influence of Tracheal Obstruction on the Efficacy of Superimposed High-frequency Jet Ventilation and Single-frequency Jet Ventilation

BACKGROUND

Both superimposed high-frequency jet ventilation (SHFJV) and single-frequency (high-frequency) jet ventilation (HFJV) have been used with success for airway surgery, but SHFJV has been found to provide higher lung volumes and better gas exchange than HFJV in unobstructed airways. The authors systematically compared the ventilation efficacy of SHFJV and HFJV at different ventilation frequencies in a model of tracheal obstruction and describe the frequency and obstruction dependence of SHFJV efficacy.

METHODS

Ten anesthetized animals (weight 25 to 31.5 kg) were alternately ventilated with SHFJV and HFJV at a set of different fHF from 50 to 600 min. Obstruction was created by insertion of interchangeable stents with ID 2 to 8 mm into the trachea. Chest wall volume was measured using optoelectronic plethysmography, airway pressures were recorded, and blood gases were analyzed repeatedly.

RESULTS

SHFJV provided greater than 1.6 times higher end-expiratory chest wall volume than HFJV, and tidal volume (VT) was always greater than 200 ml with SHFJV. Increase of fHF from 50 to 600 min during HFJV resulted in a more than 30-fold VT decrease from 112 ml (97 to 130 ml) to negligible values and resulted in severe hypoxia and hypercapnia. During SHFJV, stent ID reduction from 8 to 2 mm increased end-expiratory chest wall volume by up to 3 times from approximately 100 to 300 ml and decreased VT by up to 4.2 times from approximately 470 to 110 ml. Oxygenation and ventilation were acceptable for 4 mm ID or more, but hypercapnia occurred with the 2 mm stent.

CONCLUSION

In this in vivo porcine model of variable severe tracheal stenosis, SHFJV effectively increased lung volumes and maintained gas exchange and may be advantageous in severe airway obstruction.

High-frequency jet ventilation shortened the duration of gas embolization during laparoscopic liver resection in a porcine model

BACKGROUND

Positive pressure mechanical ventilation causes rhythmic changes in thoracic pressure and central blood flow. If entrainment occurs, it could be easier for carbon dioxide to enter through a wounded vein during laparoscopic liver lobe resection (LLR). High-frequency jet ventilation (HFJV) is a ventilating method that does not cause pronounced pressure or blood flow changes. This study aimed to investigate whether HFJV could influence the frequency, severity, or duration of gas embolism (GE) during LLR.

METHODS

Twenty-four anaesthetized piglets underwent lobe resection and were randomly assigned to either normal frequency ventilation (NFV) or HFJV (n=12 per group). During resection, a standardized injury to the left hepatic vein was created to increase the risk of GE. Haemodynamic and respiratory variables were monitored. Online blood gas monitoring and transoesophageal echocardiography were used. GE occurrence and severity were graded as 0 (none), 1 (minor), or 2 (major), depending on the echocardiography results.

RESULTS

GE duration was shorter in the HFJV group (P=0.008). However, no differences were found between the two groups in the frequency or severity of embolism. Incidence of Grade 2 embolism was less than that found in previous studies and physiological responses to embolism were variable.

CONCLUSION

HFJV shortened the mean duration of GE during LLR and was a feasible ventilation method during the procedure. Individual physiological responses to GE were unpredictable.

Frequency dependence of lung volume changes during superimposed high-frequency jet ventilation and high-frequency jet ventilation

BACKGROUND

Superimposed high-frequency jet ventilation (SHFJV) has proved to be safe and effective in clinical practice. However, it is unclear which frequency range optimizes ventilation and gas exchange. The aim of this study was to systematically compare high-frequency jet ventilation (HFJV) with HFJV by assessing chest wall volume variations (ΔEEV(CW)) and gas exchange in relation to variable high frequency.

METHODS

SHFJV or HFJV were used alternatively to ventilate the lungs of 10 anaesthetized pigs (21-25 kg). The low-frequency component was kept at 16 min(-1) in SHFJV. In both modes, high frequencies ranging from 100 to 1000 min(-1) were applied in random order and ventilation was maintained for 5 min in all modalities. Chest wall volume variations were obtained using opto-electronic plethysmography. Airway pressures and arterial blood gases were measured repeatedly.

RESULTS

SHFJV increased ΔEEV(CW) compared with HFJV; the difference ranged from 43 to 68 ml. Tidal volume (V(T)) was always >240 ml during SHFJV whereas during HFJV ranged from 92 ml at the ventilation frequency of 100 min(-1) to negligible values at frequencies >300 min(-1). We observed similar patterns for Pa(O₂) and Pa(CO₂). SHFJV provided generally higher, frequency-independent oxygenation (Pa(O₂) at least 32.0 kPa) and CO₂ removal (Pa(CO₂) ∼5.5 kPa), whereas HFJV led to hypoxia and hypercarbia at higher rates (Pa(O₂) <10 kPa and Pa(CO₂)>10 kPa at f(HF)>300 min(-1)).

CONCLUSIONS

In a porcine model, SHFJV was more effective in increasing end-expiratory volume than single-frequency HFJV, but both modes may provide adequate ventilation in the absence of airway obstruction and respiratory disease, except for HFJV at frequencies ≥300 min(-1).