Airway Opening Research Articles

A generalized equation approach for hyoid bone displacement and penetration\u2013aspiration scale analysis

Swallowing physiology includes numerous biomechanical events including displacement of the hyoid bone, which is a crucial component of airway protection and opening of the proximal esophagus. The objective of this study was to evaluate the potential relations between the trajectory of hyoid bone movement and the risk of airway penetration and aspiration during a videofluoroscopic swallowing study. Two hundred sixty-five patients were involved in this study, producing a total of 1433 swallows of various volumes consisting of thin liquid, nectar-thick liquid, and solids during a fluoroscopic exam. The anterior and posterior landmarks of the body of the hyoid bone were manually marked in each frame of each fluoroscopic video. Generalized estimation equations were applied to evaluate the relationship between penetration–aspiration scores and mathematical features extracted from the hyoid bone trajectories, while also considering the influence of other independent variables such as age, bolus volume, and viscosity. Our results indicated that penetration–aspiration scores showed a significant relation to age. The maximum anterior (horizontal) displacement of the anterior hyoid bone landmark was significantly associated with the penetration–aspiration scores. Differences in the displacement of the hyoid bone are useful observations in airway protection.Article highlightsIn this work, the potential relations between the trajectory of hyoid bone movement and the risk of airway penetration and aspiration during a videofluoroscopic swallowing study were evaluated.We extracted features from the hyoid bone trajectories and applied generalized estimation equations to investigate their relationship to penetration–aspiration scales.The results showed that the maximum anterior (horizontal) displacement of the anterior hyoid bone landmark was significantly associated with the penetration–aspiration scales.

Potential effect of pulmonary fluid viscosity on positive end-expiratory pressure and regional distribution of lung ventilation in acute respiratory distress syndrome

BackgroundComputational fluid dynamic simulations have showed that the elevated viscosity of pulmonary fluids may increase the likelihood of airway closure, thus exacerbating inhomogeneity of regional lung ventilation. Unfortunately, there have been few studies directed toward measurements of viscosity of pulmonary fluids and its effect on airway opening pressure and regional distribution of lung ventilation in acute respiratory distress syndrome. MethodsIn this study, pulmonary fluids from 8 ARDS patients were measured using a cone and plate rheometer on days 1, 3, 7 and 14 in the treatment of the disorder. Ventilator settings were simultaneously recorded, including tidal volume, positive end-expiratory pressure, fraction of inspired oxygen (FiO2), and so on. The regional distribution of lung ventilation was monitored by a bedside electrical impedance tomography system. FindingsThe results showed that rheological properties of pulmonary fluids behaved as either Newtonian or non-Newtonian across all patients studied. Significant intersubject and intrasubject variations in measured viscosities were observed, spanning ranges from approximately 1 cP to 7 × 104 cP at shear rates between 0.075–750 s−1. The product of the positive end-expiratory airway pressure and fraction of inspired oxygen was well correlated with fluid viscosity in patients with high viscosity pulmonary fluids. Furthermore, lung ventilation in these patients was highly inhomogeneous and influenced by rheology of pulmonary fluids. InterpretationThe current findings provided the direct clinical data for theoretical models of airway reopening and may have important clinical implications in explaining inhomogeneity of lung ventilation and selecting initial levels of positive end-expiratory pressure in mechanically ventilated patients.

Effectiveness of selected alternative methods of airway management by the nursing staff

Abstract Aim. The aim of the study was to assess the effectiveness of selected methods of alternative airway management by nursing staff. Material and methods. A prospective, pilot observational study was conducted on a group of 51 nurses undergoing specialization training or with specialty. Each nurse managed the airway with a laryngeal mask (LMA-Laryngeal Mask) and a laryngeal tube (LT-D-Laryngeal Tube) on a BT-CSIE trainer, and then carried out one minute ventilation using a bag valve mask, according to possessed knowledge and skills. The obtained parameters (time, pressure on the incisors, head tilt, ventilation quality) were recorded using a dedicated tablet. Statistical analysis was performed using the IBMSPSS Statistics 20 package. Results. No statistically significant differences were observed between the trials to open the airway using LMA and LT-D. Higher efficiency of LMA airway opening was demonstrated in the first trial and the average tidal volume during ventilation in relation to LT-D (LMA 547.84ml vs. LT-D 522.63ml). In addition, there was a significant difference in pressure on the incisors (LMA 6.82N vs. LT-D 4.12N). Conclusions. The effectiveness of LMA and LT-D insertion was assessed at a high level, with no significant differences between them. Variables: age, seniority, education level and type of specialization did not significantly differentiate the results obtained.

Role of ventilator and nasal interface in pressure transmission during neonatal intermittent positive pressure ventilation: A bench study.

We aimed at evaluating pressure transmission and stability during non-synchronized neonatal nasal intermittent positive pressure ventilation (NIPPV) delivered using five mechanical ventilators and three nasal interfaces. An artificial nose-throat model was connected to a mechanical analog of the infant respiratory system and a breath generator. Ventilation was administrated via a nasal mask (NM), short bi-nasal prongs (SBN), or RAM® cannula. We applied positive end-expiratory pressures (PEEP) of 5 and 10 cmH2 O, inspiratory pressures (PIP) of 15 and 30 cmH2 O, inspiratory times of 0.23, 0.42, and 0.57 s. Measurements were performed with leaks of 0, 1.5, and 4 L/min. The pressure was measured at the airways opening (PAW ) and the glottis (PGL ).The difference between set and delivered pressures (PAW ) was less than ±1 cmH2 O for all ventilators. We documented a significant difference between PAW and PGL in the presence of leaks. With 4 L/min leaks, PEEP dropped by 43%, 49%, and 63% with NM, SBP, and RAM® cannula, respectively; PIP dropped by 58%, 64%, and 74%. On average, the SD of PEEP fluctuations was ±0.60 and ±2.50 cmH2 O for PAW and PGL ; the breath-by-breath SD of PIP was ±0.77 and ±2.06 cmH2 O. During NIPPV, the PIP and PEEP transmission to the glottis is markedly lower than the set values and highly variable. The impact of leaks and nasal interface is much more significant than the differences in ventilators' performance on the efficacy of pressure transmission and stability of non-synchronized ventilator-generated NIPPV.

Vocal Fold Injection Augmentation for Post-Airway Reconstruction Dysphonia: A Case Series.

Post airway reconstruction dysphonia (PARD) is common and has a significant effect on the quality of life of patients. Vocal fold injection augmentation (VFIA) is one treatment that can be used to improve glottic insufficiency in some patients. The goal of this study was to characterize the use and outcomes of VFIA for PARD. Retrospective chart review from January 2007 to July 2018 at a tertiary pediatric care center. Consecutive patients with PARD who underwent VFIA, who had a preoperative voice evaluation and a follow-up evaluation within 3 months after VFIA (fat, carboxymethylcellulose gel, hyaluronic acid). Thirty-four patients (20 female) underwent VFIA. The mean age at the time of the injection was 13.6 years (SD 6.1). Twenty patients (58.8%) had a history of prematurity and a mean of 1.8 open airway surgeries. After injection, 29/34 patients (85.3%) noted a subjective voice improvement. The baseline Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V) overall severity score decreased by a mean of 5.7 (SD = 19.6) points, P = .12. Total pediatric Voice Handicap Index (pVHI) improved by 6.0 (SD = 19.5) points, from 57.4 (SD = 20.0) to 51.4 (SD = 17.2), P = .09. Functional pVHI subscore demonstrated a significant improvement, with a decrease of 3.4 (SD = 7.3) points, P = .02. All procedures were performed as an overnight observation and no complication occurred. Patients with PARD represent a complex subset of patients. VFIA is a straightforward intervention that may improve voice perception. Many patients reported subjective improvement despite minimal objective measurement. Further work is warranted to elucidate the role of injection in management of PARD.

Respiratory Tract Bacterial Colonization in Long-Term Tracheostomized Pediatric Patients: Comparison between Sites and Two Different Timepoints

Background and Objectives Tracheostomy lead to persistent bacterial colonization of the respiratory tract. Surgical site infection and restenosis by the pathogenic bacteria is the most fatal complication after open airway surgery. The aim of this study is to describe the culture results of larynx and tracheostoma in patients with tracheostomy and the preoperative, intraoperative culture results in patients underwent open airway surgery. Materials and Method A retrospective review was performed on 18 patients who underwent culture between 2017 and 2019. Results Pseudomonas or antibiotic resistance bacteria were identified in 11 patients out of 18 patients (61.1%); Ceftriaxone-resistant Streptococcus (38.9%), Pseudomonas (33.3%), Methicillin-resistant Staphylococcus aureus (16.7%), extended-spectrum β-lactamases (ESBL) producing Klebsiella pneumoniae (11.1%). Among 18 patients, 6 patients showed the different culture result between larynx and tracheostoma. In 4 out of 10 patients who underwent open airway surgery, the bacteria were not identified before surgery, but the bacteria were isolated in the intraoperative culture. In one patient, the bacteria detected intraoperatively were different from those detected before surgery. Conclusion Preoperative respiratory tract culture and usage of perioperative antibiotics according to the culture are necessary. It is crucial to verify the bacterial culture in both tracheostoma and larynx. And it should be performed immediately before open airway surgery. Key words: Subglottic stenosis ㆍ Tracheostomy ㆍ Bacterial culture test ㆍ Antimicrobial susceptibility test ㆍ Prophylactic antibiotics 핵심용어: 성문하협착 ㆍ ê¸°ê´€ì ˆê°œìˆ ã† ê· ë°°ì–‘ê²€ì‚¬ ㆍ í•­ìƒì œ 감수성 ㆍ ì˜ˆë°©ì  í•­ìƒì œ

Comparative Analysis of the Effectiveness of Performing Advanced Resuscitation Procedures Undertaken by Two- and Three- Person Basic Medical Rescue Teams in Adults under Simulated Conditions.

(1) Objective: Paramedics as a profession are a pillar of the State Medical Rescue system. The basic difference between a specialist and a basic team is the composition of members. The aim of the study was to benchmark the effectiveness of performing advanced resuscitation procedures undertaken by two- and three-person basic emergency medical teams in adults under simulated conditions. (2) Design: The research was observational. 200 two- and three-people basic emergency medical teams were analyzed during advanced resuscitation procedures, ALS (Advanced Life Support) in adults under simulated conditions. (3) Method: The study was carried out among professionally active and certified paramedics. It lasted over two years. The study took place under simulated conditions using prepared scenarios. (4) Results: In total, 463 people took part in the study. The analysis of the survey results indicates that the efficiency of three-person teams is superior to the activities performed by two-person teams. Three-person teams were quicker to perform rescue actions than two-person teams. The two-person teams were much quicker to assess the condition of victims than the three-person teams. The three-person teams were more likely to check an open airway. The three-person teams were more efficient in assessing the heart rhythm and current condition of victims. It was demonstrated that three-person teams were more effective during electrotherapy. The analysis demonstrated that three-person teams were significantly faster and more efficient in chest compressions. Three-person teams were less likely to use emergency airway techniques than two-person teams. The results indicate that three-person teams administered the first dose of adrenaline significantly faster than two-person teams. For the “call for help”, the three-person teams were found to be more effective. (5) Conclusion: Paramedics in three-person teams work more effectively, make a proper assessment of heart rhythm and monitor when taking advanced actions. The quality of ventilation and BLS in both groups studied is insufficient. Numerous errors have been observed in two-person teams during pharmacotherapy.

Positive end-expiratory pressure in COVID-19-related ARDS: Do not forget the airway closure.

Airway closure is a physiological phenomenon in which the distal airways are obstructed when the airway pressure drops below the airway opening pressure. We assessed this phenomenon in 27 patients with coronavirus disease 2019-related acute respiratory distress syndrome. Twelve (44%) patients had an airway opening pressure above 5 cmH2O. The median airway opening pressure was 8 cmH2O (interquartile range, 7–10), with a maximum value of 17 cmH2O. Three patients had a baseline positive end-expiratory pressure lower than the airway opening pressure.

Airway Surgery for Laryngotracheal Stenosis During the COVID-19 Pandemic: Institutional Guidelines

ObjectiveThe management of laryngotracheal stenosis is challenging, as patients usually require in-time interventions. The current coronavirus disease 2019 (COVID-19) pandemic has added unique challenges to this procedure. The presence of the virus in high concentrations in the aerodigestive tract and the need for an open airway during surgery can increase the risk of aerosolization of the virus and subsequent infection of the surgical, anesthetic, and operating room (OR) personnel.DesignRetrospective cohort study.SettingUniversity hospital.ParticipantsPatients who underwent airway interventions between March and October 2020.InterventionsA protocolized strategy was initiated during the COVID-19 pandemic to facilitate the consistent management of all patients undergoing airway interventions.Measurements and Main ResultsDuring a seven-month period, 34 patients were managed with this policy. All threatened airways were managed successfully and no healthcare workers dealing with such procedures were infected. Priorities during the current novel coronavirus pandemic are ensuring the safety of healthcare professionals and offering urgent bronchoscopic and surgical airway interventions for patients with progressive symptoms and threatened airways.ConclusionsSurgical and bronchoscopic management of laryngotracheal stenosis presents a unique challenge during the COVID-19 pandemic, requiring careful consideration of patient triage and the development of protocols that minimize risk to patients and healthcare professionals. Close collaboration between thoracic surgeons and anesthesiology teams is essential to safely navigate and handle these threatened airways while mitigating the risk of viral aerosolization.

An oropharyngeal device for airway management of conscious and semiconscious patients: A randomized clinical trial.

ObjectiveNo oropharyngeal devices exist for use in conscious and semiconscious trauma patients during emergency evacuation, transport, or resuscitation. We aimed to test the hypotheses that the ManMaxAirway (MMA) is better tolerated than the standard Guedel‐style device in awake volunteers and that it produces a jaw thrust and improves air flow.MethodsThis was a randomized cross‐over study of healthy volunteers with either the MMA or standard device. The primary outcome of tolerability was defined as maintaining the device in place for 60 seconds. Secondary outcomes included respiratory system function and jaw thrust. Resistance to airflow through the device lumen was measured in situ and when placed in subjects in the pulmonary laboratory alone. Jaw thrust was quantified as displacement between the mandibular condyle and condylar fossa apex relative to baseline visualized with magnetic resonance imaging (MRI).ResultsWe enrolled 19 subjects. Of these, a convenience sample of 5 individuals was selected for MRI; the remaining individuals (n = 14) were randomized for the cross‐over study. All 14 subjects were able to maintain the MMA for 60 seconds compared with 2/14 (14%) with the standard device (odds ratio, 145; 95% confidence interval, 6.3‐3314). Subjects reported that the experimental device was more comfortable and its placement did not trigger the gag reflex. Airway resistance produced by the MMA in an oscillatory flow model was nearly an order of magnitude lower than that of the standard device (experimental vs standard, 8 Hz—0.092 vs 0.786 cmH20·s/L; 15 Hz—0.193 vs 1.321 cmH20·s/L). Rapid induction of the gag reflex precluded further measurements with the standard device. Forced oscillation pulmonary testing in conscious volunteers with and without the MMA demonstrated that the device decreased respiratory system resistance to airflow and reduced respiratory elastance (31% ± 8% and 44% ± 13.4%, respectively; P < 0.05). MRIs of the subjects (n = 5) with the MMA in place showed a significant jaw thrust compared with baseline (7 ± 1 mm).ConclusionsThe MMA proved well tolerated in conscious subjects, resulting in an opening of the anatomic airway and a decreased resistance to airflow.

A pre experimental study to assess the effectiveness of planned teaching program regarding essential new born care on knowledge of post natal mothers in selected hospital of Durg Chhattisgarh

Introduction: Essential new born care is most important at birth. New born care is the term given to a new born baby from the time of birth up to 28 days of life. Its included essential new born care include immediate basic care of neonate and routine care of neonate. Immediate basic care of newborn of the newborn at birth included maintenance of temperature, establishment of open airway, initial of breathing and maintenance of circulation. Daily routine care of neonates include warmth, breast feeding, skin care, baby bath, care of eye, clothing of baby, general care, observation, weight recording, immunization, follow up and advice.Methods research approach: Evaluative research approach. Research design, pre experimental research design (one group pre text post text design). The conceptual framework based of “conceptual Framework based on modified system model. The setting for this study was the selected areas of District hospital Durg, Chhattisgarh. The tools developed which include,Section 1: Socio demographic data containing sample characteristics would be analyzed using frequency and percentage.Section II: Mean median slandered deviation and mean percentage of pre test and post test knowledge scores would be computed.Section III: The significant difference between the mean retest and pos t test knowledge score would be calculated using paired t test.Section IV: The association between post test knowledge with selected demographic variables would be determined by the chi- square test.Tools validity was done and tools found reliable, study found feasible after pilot study.Result: it has been observed that in this study pretest and posttest design was used. The population for the present study comprised post natal mothers of seleted hospitals Durg. Total 40 samples were taken. sample was collected through the use of purposive sampling technique. To ensure reliability of tool data of the structured knowledge questionnaire was analyzed by split half method and the reliability coefficient was calculated through using spearman Brown prophecy formula. The reliability co-efficient of the tool was found to be r= 0.816. Hence the tool was found to be valid, reliable and feasible.Section 1: Socio demographic data.Section II: Assess the level of pre test and post test knowledge on post natal mothers regarding new born careSection III: Evaluate effectiveness of planed teaching program by comparing pre and post test knowledge score.Section IV: The association between post test knowledge with selected demographic variables.Conclusion: The study findings showed that there was significant increase in the knowledge of post natal mothers after giving of planned teaching programme regarding new born care. Hence it was concluded that planned teaching programme has been an effective method to increase knowledge of post natal others regarding new born care.

Protocol to maintain ECT in COVID-19 pandemic

IntroductionElectroconvulsive therapy is a highly effective treatment for severe psychopharmacological resistant patients but it is also a procedure that involves open airway management and has been considered as an aerosol generating procedure. The COVID-19 pandemic, has resulted in reduction in ECT services internationally. The COVID-19 pandemic has dramatically and rapidly transformed hospitals in heavily affected areas, decreasing mental health services. The need to locate critical patients in spaces intended for anesthesia, where we usually administered ECT, has forced us to decrease the number of procedures and be highly selective. In the same way, continuation and maintenance ECT (m-ECT) have also been dramatically reduced. The risk of contagion urged us to develop a protocol involving other areas of the hospitalObjectivesTo create a safe circuit from admission to the hospital to the ECT including emergency room and psychiatric WardMethodsReview of the tliterature and published protocols Workshops with Preventive Medicine, Anaesthesia and Emergency Service to elaborate a protocol Submission of the protocol to Management of the HospitalResultsThe protocol (Figure 1) began with the screening for COVID-19 in every patient. If the PCR was (+) the patient was not excluded. We moved treatment from the PACU into the OR and if a patient tested positive It was determined that the ECT was administered in the ORThat was provided with negative pressure. Circuits were established within the Psychiatric Ward and in the areas of the hospital involved to reduce risks and patients remained isolated until negative test was confirmed The number of persons present in the treatment room was kept to the absolute minimum required and appropriate personal protective equipment was used, as prescribed by the WHOConclusionsWe must keep in mind treating the most vulnerable of our patients. ECT should be seen as an essential medical procedure and made availableDisclosureNo significant relationships.

Comparison of tracheal resection outcomes at a university hospital vs county hospital setting.

ObjectivesTo evaluate the role of hospital setting on outcomes in open airway surgery by comparing patients who underwent surgery (cricotracheal resection [CTR] or tracheal resection [TR]) at a publicly funded county hospital vs a private university hospital.MethodsRetrospective chart review of patients undergoing CTR or TR at two institutions; a private university hospital and a publicly funded county hospital from September 2014 to September 2019. Length of intensive care unit (ICU) stay, total time to discharge, minor and major complications were the primary endpoints. Significance was defined as a P‐value less than .05.ResultsThere were a total of 43 patients (17 county, 26 university) who had CTR or TR during the study period. Length of stay outcomes was reported as mean length of stay ± SD. There was a significant difference in ICU stay at the county hospital (7.17 (±5.36 days) compared to the university hospital (2.52 ± 1.85 days, P < .003) and a nearly significant total length of stay difference at the county hospital (12.4 ± 9.06 days) compared to the university hospital (7.84 ± 4 days, P < .072) There was overall a low incidence of complications but slightly more in the county compared to the university population.ConclusionPatients who underwent open airway surgery at the county hospital were more likely to have a longer ICU stay and slight increase in complications despite having a lower ASA (American Society of Anesthesiologists) classification and younger age. These outcomes are multifactorial and may be related to poorer access to primary care preoperatively leading to delay in diagnosis and treatment, poorly controlled or undiagnosed medical comorbidities, and differences in hospital resources.Level of EvidenceIV.

Inspiratory Efforts, Positive End-Expiratory Pressure, and External Resistances Influence Intraparenchymal Gas Redistribution in Mechanically Ventilated Injured Lungs

BackgroundPotentially harmful lung overstretch can follow intraparenchymal gas redistribution during mechanical ventilation. We hypothesized that inspiratory efforts characterizing spontaneous breathing, positive end-expiratory pressure (PEEP), and high inspiratory resistances influence inspiratory intraparenchymal gas redistribution.MethodsThis was an experimental study conducted on a swine model of mild acute respiratory distress syndrome. Dynamic computed tomography and respiratory mechanics were simultaneously acquired at different PEEP levels and external resistances, during both spontaneous breathing and controlled mechanical ventilation. Images were collected at two cranial–caudal levels. Delta-volume images (ΔVOLs) were obtained subtracting pairs of consecutive inspiratory images. The first three ΔVOLs, acquired for each analyzed breath, were used for the analysis of inspiratory pendelluft defined as intraparenchymal gas redistribution before the start of inspiratory flow at the airway opening. The following ΔVOLs were used for the analysis of gas redistribution during ongoing inspiratory flow at the airway opening.ResultsDuring the first flow-independent phase of inspiration, the pendelluft of gas was observed only during spontaneous breathing and along the cranial-to-caudal and nondependent-to-dependent directions. The pendelluft was reduced by high PEEP (p < 0.04 comparing PEEP 15 and PEEP 0 cm H2O) and low external resistances (p < 0.04 comparing high and low external resistance). During the flow-dependent phase of inspiration, two patterns were identified: (1) gas displacing characterized by large gas redistribution areas; (2) gas scattering characterized by small, numerous areas of gas redistribution. Gas displacing was observed at low PEEP, high external resistances, and it characterized controlled mechanical ventilation (p < 0.01, comparing high and low PEEP during controlled mechanical ventilation).ConclusionsLow PEEP and high external resistances favored inspiratory pendelluft. During the flow-dependent phase of the inspiration, controlled mechanical ventilation and low PEEP and high external resistances favored larger phenomena of intraparenchymal gas redistribution (gas displacing) endangering lung stability.

Estimating Airway Opening Pressure, Trapped Gas Volume, and Hidden Intrinsic Positive End-Expiratory Pressure in Mechanically Ventilated Patients.

Estimating Airway Opening Pressure, Trapped Gas Volume, and Hidden Intrinsic Positive End-Expiratory Pressure in Mechanically Ventilated Patients.

The low value of pre-decannulation capped overnight ICU monitoring for pediatric patients

ObjectiveTo determine the value of pre-decannulation capped overnight ICU monitoring for assessing decannulation-readiness in pediatric patients. MethodsThis study included all pediatric patients, age 18 and under, with a tracheostomy attempting decannulation at the University of Michigan between 2013 and 2018. Patients who underwent major airway reconstruction immediately prior to decannulation were excluded. Descriptive and comparative statistics were calculated to compare the sub-group of patients who underwent pre-decannulation capped overnight ICU monitoring to those who did not. Results125 pediatric patients attempted decannulation for a total of 126 attempts with 105 attempts being eligible for inclusion. 75 eligible attempts included pre-decannulation capped overnight ICU monitoring, while 30 did not. Subsequent rates of successful decannulation were 97.33% (73/75) and 100.00% (30/30), respectively (P = 0.366; 95% CI -8.818-9.260). The pre-decannulation capped overnight ICU monitoring passing rate was 98.67% (74/75) despite a complication rate of 5.33% (4/75). Post-decannulation, 98.08% (102/104) of decannulated patients were monitored inpatient for a minimum of 24 h DiscussionWith similar rates of successful decannulation among both sub-groups and previous research demonstrating sufficient ambulatory testing accurately predicts successful decannulation, pre-decannulation capped overnight ICU monitoring is a low-value, high-cost test that can be safely discontinued without compromising patient care. Notably, our study excluded patients undergoing open airway reconstruction immediately prior to decannulation. The 24-h monitoring post-decannulation serves as a safety net for individuals who ultimately fail decannulation.

In Vitro Estimation of Relative Compliance during High-Frequency Oscillatory Ventilation

High-frequency oscillatory ventilation (HFOV), which uses a small tidal volume and a high respiratory rate, is considered a type of protective lung ventilation that can be beneficial for certain patients. A disadvantage of HFOV is its limited monitoring of lung mechanics, which complicates its settings and optimal adjustment. Recent studies have shown that respiratory system reactance (Xrs) could be a promising parameter in the evaluation of respiratory system mechanics in HFOV. The aim of this study was to verify in vitro that a change in respiratory system mechanics during HFOV can be monitored by evaluating Xrs. We built an experimental system consisting of a 3100B high-frequency oscillatory ventilator, a physical model of the respiratory system with constant compliance, and a system for pressure and flow measurements. During the experiment, models of different constant compliance were connected to HFOV, and Xrs was derived from the impedance of the physical model that was calculated from the spectral density of airway opening pressure and spectral cross-power density of gas flow and airway opening pressure. The calculated Xrs changed with the change of compliance of the physical model of the respiratory system. This method enabled monitoring of the trend in the respiratory system compliance during HFOV, and has the potential to optimize the mean pressure setting in HFOV in clinical practice.

Tracheocutaneous Fistula After Pediatric Open Airway Reconstruction.

Tracheocutaneous fistula (TCF) is a common occurrence after pediatric tracheostomy decannulation. However, the persistence of TCF after staged reconstruction of the pediatric airway is not well-described. The primary objective was to determine the rate of persistent TCF after successful decannulation in children with staged open airway reconstruction. A case series with chart review of children who underwent decannulation after double-stage laryngotracheal reconstruction between 2017 and 2019. A total of 26 children were included. The most common open airway procedure was anterior and posterior costal cartilage grafting (84.6%, 22/26). Median age at decannulation was 3.4 years (IQR: 2.8-4.3) and occurred 7.0 months (IQR: 4.3-10.4) after airway reconstruction. TCF persisted in 84.6% (22/26) of children while 15.4% (4/26) of stomas closed spontaneously. All closures were identified by the one-month follow-up visit. There was no difference in age at tracheostomy (P = .86), age at decannulation (P = .97), duration of tracheostomy (P = .43), or gestational age (P = .23) between stomas that persisted or closed. Median diameter of stent used at reconstruction was larger in TCFs that persisted (7.0 mm vs 6.5 mm, P = .03). Tracheostomy tube diameter (P = .02) and stent size (P < .01) correlated with persistence of TCF on multivariable logistic regression analysis. There were 16 surgical closure procedures, which occurred at a median of 14.4 months (IQR: 11.4-15.4) after decannulation. Techniques included 56.3% (9/16) by primary closure, 18.8% (3/16) by secondary intention and 25% (4/16) by cartilage tracheoplasty. The overall success of closure was 93.8% (15/16) at latest follow-up. Persistent TCF occurs in 85% of children who are successfully decannulated after staged open airway reconstruction. Spontaneous closure could be identified by 1 month after decannulation and was more likely when smaller stents and tracheostomy tubes were utilized. Surgeons should counsel families on the frequency of TCF and the potential for additional procedures needed for closure.

Pediatric Open Airway Reconstruction

Subglottic stenosis (SGS) and tracheal stenosis (TS) can be congenital or acquired. Ongoing improvements in neonatal care have led to an increased number of infants with prolonged intubation and tracheostomy. Both of these interventions have led to an increase in SGS and TS and management of these lesions can be challenging. A wide array of endoscopic and open techniques exist to manage these issues. This article aims to review previous and current literature on open airway reconstruction to guide care for these children. Experience and expertise in airway surgery have shifted recent research towards non-airway outcome measures such as swallowing and voice, though the primary treatment objective remains decannulation. Various open surgical options as slide tracheoplasty, laryngotracheal reconstruction, and partial cricotracheal resection and anastomosis are available for correcting laryngotracheal stenosis. The choice of the surgery should be based on demography and characteristics of the stenosis found during endoscopy and the associated comorbidities of the patient. Open airway reconstruction for treatment of LTS is effective but careful preoperative evaluation and patient selection are important. Ongoing research focuses on improving swallowing and voice outcomes.

Comparison between lignocaine nebulization and airway nerve blocks for awake fiberoptic nasotracheal intubation in oral cancer surgery patients: Running title: Airway management in oral cancer patients

Intro duction: Awake fiberoptic bronchoscope-guided intubation is the preferred airway management strategy in a patient with a difficult airway and limited mouth opening. The aim is to compare the efficacy of nebulization and airway nerve block using lignocaine to provide airway anesthesia in awake patients using fiberoptic bronchoscope for nasal intubation to make the patient comfortable, cooperative, and agreeable. Methods: In this randomized, prospective, single-blinded study, sixty adult patients scheduled for oral cancer surgeries were divided into two equal groups. Nebulization with 4% lignocaine (10 ml) was performed in Group N, and superior bilateral laryngeal and trans-laryngeal recurrent laryngeal nerve blocks used 2% lignocaine (2 ml) were given in Group B. Nasotracheal intubation using fiberoptic bronchoscope were performed. Intravenous midazolam and fentanyl were used for sedation and analgesia. We recorded the ease of intubation, coughing episodes, vocal cord status, hemodynamic variables, patient recall, and lignocaine toxicity. Student's t-test and Chi-square tests were used for appropriate data. Statistical significance was considered for P &lt; 0.05 (SPSS Version 20, IBM, USA). Results: The intubation time was shorter with better intubating conditions in Group B (120.3 ± 42.6 s) than Group N (200.4 ± 60.3 s) (P &lt; 0.001). Cough severity and patient recall for untoward effects were lower in Group B. Intubation were done successfully in all patients. Conclusion: Airway nerve blocks provided better airway anesthesia characterized by easier fiberoptic intubation and patient comfort than lignocaine nebulization. Nebulization can be considered a suitable alternative when nerve blocks are not feasible due to distorted neck anatomy.