Adverse Airway Research Articles

Role of High Flow Nasal Cannula (HFNC) for Pre-Oxygenation Among Pregnant Patients

With an increasing understanding of respiratory physiology and pathology, many new oxygen delivery devices have been introduced lately. Among them, high flow nasal cannula (HFNC) seems a promising modality that can deliver heated and humidified flows higher than the peak inspiratory flow at high FiO2 (fractional inspired oxygen), hence decreasing the work of breathing without causing discomfort to the patient. Applications of HFNC have escalated for use in multiple areas besides perioperative period over the last decade. The use of HFNC in obstetric population is particularly intriguing as this population is at risk of adverse airway related events. Hence, this narrative review focuses upon the role of HFNC for pre-oxyenation of pregnant patients in peripartum and in intensive care units. We have reviewed the current state of knowledge and the future prospects of HFNC use in obstetric setting.

Efficacy and Safety of Flexible Laryngeal Mask Ventilation in Otologic Surgery: A Retrospective Analysis.

BackgroundFlexible laryngeal mask airways (FLMAs) ventilation have been widely used as airway devices during general anesthesia, especially in otologic surgery. However, the current literature reports that the clinical success and failure rates for FLMA usage are quite different, and there remains a paucity of data regarding factors associated with FLMA failure and complications related to FLMA usage.PurposeTo evaluate the success and failure rates of FLMA usage in otologic surgery, the factors associated with FLMA failure and complications related to FLMA usage.Patients and MethodsAll patients who underwent otologic surgery, including middle ear and mastoid procedures, under general anesthesia at a large tertiary general hospital from 2015 to 2019 were reviewed. The primary outcome was the FLMA failure rate, defined as any airway event requiring device removal and tracheal intubation, including primary and secondary failure. The secondary outcomes were specific clinical factors, including patient sex, age, weight, American Society of Anesthesiologists (ASA) classification, body mass index (BMI) and duration of surgery, which were analyzed as related risk factors.ResultsAmong 5557 patients with planned FLMA use, the final success rate was 98.5%. Sixty-seven percent of the failures occurred during initial introduction of the FLMA, 8% occurred after head and neck rotation, and 25% occurred during the procedures. Two independent clinical factors associated with FLMA failure were male sex and age. Respiratory complications were observed in 0.61% of patients, and the rate of severe nerve and tissue damage associated with FLMA use was 0.05.ConclusionThis study demonstrates a high success rate of 98.5% for FLMA use in adults undergoing otologic surgery with rare adverse airway events and injuries complications. Two independent risk factors require attention and thorough and accurate management is necessary for every clinician.

Incidence of Adverse Perioperative Airway Complications in Obese Non-Pregnant and Pregnant Patients Undergoing General Anesthesia

Objective: Airway complications in obese patients are a major concern during surgical operation. This study aimed to determine the incidence of airway- and respiratory-related anesthetic complications for obese (including maternal) patients undergoing general anesthesia.Materials and Methods: This multicenter, retrospective, observational study evaluated obese female patients (BMI≥ 30 kg/m2), both non-pregnant and pregnant, undergoing general anesthesia in 5 hospitals across Thailand during May 2013 - August 2016. The primary observation was anesthesia-related airway complications (difficult and failed intubations, aspiration, desaturation, and airway injuries) detected during anesthesia. An analysis was performed to compare the incidents of the adverse events and to determine the risk factors for airway-related adverse events in both groups.Results: There were 1,347 obese patients enrolled (777 non-pregnant and 570 pregnant). The overall incidence of airway and respiratory complications was observed in 129 patients (9.6%), with a higher rate in pregnant patients (12.5% vs. 7.5%; p<0.05). The most common complications were desaturation (5.6%) followed by airway injuries (3.6%) and difficult intubation (1.5%). The factors significantly associated with adverse airway-related events were obesity class II (OR=1.63 [1.05–2.54]), obesity class III (OR=2.25 [1.19–4.25]), pregnancy (OR=1.73 [1.18–2.54]), Mallampati classifications III–IV (OR=1.69 [1.16–2.48]), and neck circumference <43 cm (OR=3.33 [1.02-10.81]), p<0.05).Conclusion: The incidence of the anesthesia-related airway and respiratory complications was 9.6%, with a higher rate in pregnant patients. The most common adverse airway event was desaturation. However, the frequency of serious airway events was low.

Role of endotracheal tube size on nasal and laryngeal morbidity during awake fiberoptic nasotracheal intubation: A Randomized controlled trial.

Background and Aims:Awake fibreoptic nasotracheal intubation is associated with adverse airway and hemodynamic complications. The aim of this study was to evaluate the role of endotracheal tube size on nasal and laryngeal morbidity during awake fibreoptic-guided nasotracheal intubation.Material and Methods:Eighty patients recruited to undergo awake fibreoptic intubation were randomly allocated to Group C (standard size endotracheal tube) and Group S (small size endotracheal tube followed by exchange to standard size using Airway Exchange Catheter under general anesthesia). Nasal morbidity was assessed by incidence of epistaxis, olfactory acuity, and mucociliary clearance. Patient discomfort during intubation was assessed using grimace score and hemodynamic parameters were recorded. Postoperatively, the incidence of nasal and laryngeal injury was recorded using nasendoscopy and telelaryngoscopy, respectively.Results:Demographic profile between the two groups was comparable. Epistaxis was noted in 47.5% of patients in group C as compared to 12.5% in group S. Postoperative olfactory acuity was decreased [2 (1-4) vs 4 (2-5)] and saccharin clearance time was prolonged (314 s vs 134 s) in Group C as compared to Group S. (P-value <0.001) Higher grimace score [2 (1-3) vs 1 (0-2)] and increased hemodynamic response was demonstrated in Group C. (P-value <0.001) Incidence of nasal injury [2 (1-4) vs 1 (0-2)] and laryngeal injury [1 (0-2) vs 0 (0-2)] was more in Group C as compared to Group S.Conclusion:Awake fibreoptic nasotracheal intubation with small size endotracheal tube followed by exchange to standard size under general anesthesia reduces nasal, laryngeal, and hemodynamic complications.

Respiratory adverse events associated with deep propofol sedation during upper gastrointestinal procedures in children

Background/Aims: Upper airway stimulation with endoscopes and pH-impedance probes during deep propofol sedation confers unknown risk for associated respiratory adverse airway events. This report quantifies frequencies of such events and airway rescue interventions associated with Esophagogastroduodenoscopies (EGD) and multi-channel intraluminal acid detection impedance probe (MIIP) placements. Methods: This was a prospective observational study regarding occurrence of adverse respiratory events in 42 children undergoing propofol sedated EGDs and MIIP placements: Group 1. (n=21 EGDs), Group2 (n=21 EGDs before MIIP), Group 3. (n=21 during MIIP). Results: All procedures were successfully completed using deep propofol sedation. Respiratory events were transient and associated with no morbidity or mortality. Nearly half of each group experienced a respiratory event. “Partial airway obstruction” during 42 EGDs occurred in 28.6% and responded to simple airway interventions. “Complete airway obstruction” occurred during 1/42 EGDs and 2/21 MIIPs. Throughout MIIP placement, endoscopic visualization of the glottis was maintained and unnecessary stimulation of the glottis was avoided; nonetheless, complete airway obstruction occurred in 2/21. Advanced airway rescue maneuvers were not required in either instance. Conclusions: Respiratory adverse events commonly occurred during EGDs and MIIP placements. All events were successfully rescued by simple airway interventions.

Operations and outcomes of a Hospital-wide Emergency Airway Response Team (HEART) in a quaternary academic children's hospital.

To improve pediatric airway management outside of the operating room, a Hospital-wide Emergency Airway Response Team (HEART) program composed of anesthesiology, otorhinolaryngology, and respiratory therapy clinicians was developed. To report processes and outcomes of HEART activations in a quaternary academic children's hospital. A retrospective observational cohort study between January 2017 and December 2019. Local airway emergency database was reviewed for HEART activations. Additional safety data was obtained from patients' electronic health records. Adverse airway outcomes, either adverse tracheal intubation-associated events or oxygen desaturation (SpO2 <80%). We compared airway management by primary teams before HEART arrival and by HEART after arrival. Of 96 HEART activations, 36 were from neonatal intensive care unit, 35 from pediatric and cardiac intensive care units, 14 from emergency department, and 11 from inpatient wards. 56 (62%) children had airway anomalies and 41/96 (43%) were invasively ventilated. Median HEART arrival time was 5min (interquartile range, 3-5). 56/96 (58%) required insertion of an advanced airway (supra/extra-glottic airway, endotracheal tube, tracheostomy tube). HEART succeeded in establishing a definitive airway in 53/56 (94%). Adverse airway outcomes were more common before (56/96, 58%) versus after HEART arrival (28/96, 29%; absolute risk difference 29%; 95% confidence interval 16, 41%; p<.001). Oxygen desaturation occurred more frequently before (46/96, 48%) versus after HEART arrival (24/96, 25%; absolute risk difference 23%; 95% confidence interval 11, 35%; p=.02). Cardiac arrests were more common before (9/96, 9%) versus after HEART arrival (3/96, 3%). Multiple (≥3) intubation attempts were more frequent before (14/42, 33%) versus after HEART arrival (9/46, 20%; absolute risk difference -14%; 95% confidence interval -32, 5%; p=.15). A multidisciplinary emergency airway response team plays an important role in pediatric airway management outside of the operating room. Adverse airway outcomes were more frequent before compared to after HEART arrival.

Optimum time of LMA ProSeal removal in adult patients undergoing isoflurane anesthesia: A randomized controlled trial.

Background and Aims:Optimum timing of laryngeal mask airway (LMA) removal after general anesthesia with isoflurane is debatable. The objective was to investigate the potential benefits of removing LMA ProSeal at ≤0.4 Minimum alveolar concentration (MAC) isoflurane over awake and “deep plane” extubation after short duration laparoscopic gynecological surgery.Material and Methods:In this prospective randomized trial 90 adult female patients undergoing elective laparoscopic surgery under general anesthesia using LMA ProSeal™ as airway device were included. At the end of surgery, LMA ProSeal™ was removed when the patient was awake, could open mouth following verbal command (Group A); at MAC ≤0.4 (Group B); or at MAC of 0.6 (Group C). Adverse airway events like nausea, vomiting, airway obstruction, coughing, bucking, laryngospasm were noted. Statistical analyses were done by SPSS statistical software (IBM SPSS Statistics for Mac OS X, Version 21.0. IBM Corp, Armonk, NY).Results:Baseline demographic characteristics were comparable in all three groups. Coughing or bucking at the time of LMA removal was higher in group A (P = 0.004). Snoring and airway obstruction after LMA removal was significantly higher in group C compared to group A and group B (P = 0.002 and P = 0.011, respectively). There was significant change in mean arterial pressure and heart rate between before and after LMA removal on group A (P = 0.008 and P < 0.001, respectively) but not in other groups.Conclusion:MAC ≤0.4 can be considered optimum depth of anesthesia for removal of LMA Proseal in adult patients undergoing isoflurane anesthesia.

So Good It Hurts?

So Good It Hurts?

The Prevalence of Difficult Airway in Children With Beckwith-Wiedemann Syndrome: A Retrospective Cohort Study.

Beckwith-Wiedemann syndrome (BWS) is the most common congenital overgrowth disorder with an incidence of approximately 1 in 10,000 live births. The condition is characterized by lateralized overgrowth, abdominal wall defects, macroglossia, and predisposition to malignancy. Historically, children with BWS have been presumed to have difficult airways; however, most of the evidence to support this has been anecdotal and derived from case reports. Our study aimed to determine the prevalence of difficult airway in patients with BWS. We hypothesized that most patients with BWS would not have difficult airways. We retrospectively reviewed the electronic medical records of patients enrolled in our institution's BWS registry. Patients with a molecular diagnosis of BWS who were anesthetized between January 2012 and July 2019 were included for analysis. The primary outcome was the presence of difficult airway, defined as difficult facemask ventilation, difficult intubation, or both. We defined difficult intubation as the need for 3 or more tracheal intubation attempts and the need for advanced airway techniques (nondirect laryngoscopy) to perform tracheal intubation or a Cormack and Lehane grade ≥3 during direct laryngoscopy. Secondary objectives were to define predictors of difficult intubation and difficult facemask ventilation, and the prevalence of adverse airway events. Generalized linear mixed-effect models were used to account for multiple anesthesia events per patient. Of 201 BWS patients enrolled in the registry, 60% (n = 122) had one or more documented anesthetics, for a total of 310 anesthetics. A preexisting airway was present in 22 anesthetics. The prevalence of difficult airway was 5.3% (95% confidence interval [CI], 3.0-9.3; 18 of 288) of the cases. The prevalence of difficult intubation was 5.2% (95% CI, 2.9-9.4; 12 of 226). The prevalence of difficult facemask ventilation was 2.9% (95% CI, 1.4-6.2; 12 of 277), and facemask ventilation was not attempted in 42 anesthetics. Age <1 year, macroglossia, lower weight, endocrine comorbidities, plastics/craniofacial surgery, tongue reduction surgery, and obstructive sleep apnea were associated with difficult airways in cases without a preexisting airway. About 83.8% (95% CI, 77.6-88.5) of the cases were intubated with a single attempt. Hypoxemia was the most common adverse event. The prevalence of difficult tracheal intubation and difficult facemask ventilation in children with BWS was 5.2% and 2.9%, respectively. We identified factors associated with difficult airway, which included age <1 year, macroglossia, endocrine abnormalities, plastics/craniofacial surgery, tongue reduction surgery, and obstructive sleep apnea. Clinicians should anticipate difficult airways in patients with these factors.

The impact of topical lidocaine and timing of LMA removal on the incidence of airway events during the recovery period in children: a randomized controlled trial

BackgroundThe timing of laryngeal mask airway (LMA) removal remains undefined. This study aimed to assess the optimal timing for LMA removal and whether topical anesthesia with lidocaine could reduce airway adverse events.MethodsThis randomized controlled trial assessed one-to-six-year-old children with ASA I-II scheduled for squint correction surgery under general anesthesia. The children were randomized into the LA (lidocaine cream smeared to the cuff of the LMA before insertion, with mask removal in the awake state), LD (lidocaine application and LMA removal under deep anesthesia), NLA (hydrosoluble lubricant application and LMA removal in the awake state) and NLD (hydrosoluble lubricant application and LMA removal in deep anesthesia) groups. The primary endpoint was a composite of irritating cough, laryngeal spasm, SpO2 < 96%, and glossocoma in the recovery period in the PACU. The secondary endpoints included the incidence of pharyngalgia and hoarseness within 24 h after the operation, duration of PACU stay, and incidence of agitation in the recovery period. The assessor was unblinded.ResultsEach group included 98 children. The overall incidence of adverse airway events was significantly lower in the LA group (9.4%) compared with the LD (23.7%), NLA (32.6%), and NLD (28.7%) groups (P=0.001). Cough and laryngeal spasm rates were significantly higher in the NLA group (20.0 and 9.5%, respectively) than the LA (5.2 and 0%, respectively), LD (4.1 and 1.0%, respectively), and NLD (9.6 and 2.1%, respectively) groups (P=0.001). Glossocoma incidence was significantly lower in the LA and NLA groups (0%) than in the LD (19.6%) and NLD (20.2%) groups (P< 0.001). At 24 h post-operation, pharyngalgia incidence was significantly higher in the NLA group (15.8%) than the LA (3.1%), LD (1.0%), and NLD (3.2%) groups (P< 0.001).ConclusionsLMA removal in the awake state after topical lidocaine anesthesia reduces the incidence of postoperative airway events.Trial registrationChiCTR, ChiCTR-IPR-17012347. Registered August 12, 2017.

The role of TRPA1 and TRPV4 channels in bronchoconstriction and plasma extravasation in airways of rats treated with captopril

Angiotensin-converting enzyme inhibitors (ACEis) may cause adverse airway events, such as cough and angioedema, due to a reduction in bradykinin breakdown and consequent activation of bradykinin type 2 receptor (B2 receptor). Recent studies have shown that bradykinin can also sensitize pro-inflammatory receptors such as the transient receptor potential ankyrin 1 (TRPA1) and vanilloid 4 (TRPV4), which are implicated in several inflammatory airway diseases. Based on these considerations, the aim of this study was to understand the role of TRPA1 and TRPV4 channels in the bronchoconstrictive response and plasma extravasation in the trachea of rats pretreated with captopril. Using methods to detect alterations in airway resistance and plasma extravasation, we found that intravenous (i.v.) administration of bradykinin (0.03–0.3 μmol/kg, B2 receptor agonist), allyl isothiocyanate (100–1000 μmol/kg, TRPA1 agonist) or GSK1016790A (0.01–0.1 μmol/kg, TRPV4 agonist), but not des-arg9-bradykinin (DABK; 100–300 μmol/kg, B1 receptor agonist), induced bronchoconstriction in anaesthetized rats. In doses that did not cause significant bronchoconstriction, bradykinin (0.03 μmol/kg) or allyl isothiocyanate (100 μmol/kg), but not GSK1016790A (0.01 μmol/kg) or DABK (300 μmol/kg) induced an increased bronchoconstrictive response in rats pretreated with captopril (2.5 mg/kg, i.v.). On the other hand, in rats pretreated with captopril (5 mg/kg, i.v.), an increased bronchoconstrictive response to GSK1016790A (0.01 μmol/kg) was observed. The bronchoconstrictive response induced by bradykinin in captopril-pretreated rats was inhibited by intratracheal treatment (i.t.) with HC030031 (300 μg/50 μl; 36 ± 9%) or HC067047 (300 μg/50 μl; 35.1 ± 16%), for TRPA1 and TRPV4 antagonists, respectively. However, the co-administration of both antagonists did not increase this inhibition. The bronchoconstriction induced by allyl isothiocyanate in captopril-pretreated rats (2.5 mg/kg) was inhibited (58.3 ± 8%) by the B2 receptor antagonist HOE140 (10 nmol/50 μl, i.t.). Similarly, the bronchoconstriction induced by GSK1016790A in captopril-pretreated rats (5 mg/kg) was also inhibited (84.2 ± 4%) by HOE140 (10 nmol/50 μl, i.t.). Furthermore, the plasma extravasation induced by captopril on the trachea of rats was inhibited by pretreatment with HC030031 (47.2 ± 8%) or HC067047 (38.9 ± 8%). Collectively, these findings support the hypothesis that TRPA1 and TRPV4, via a B2 receptor activation-dependent pathway, are involved in the plasma extravasation and bronchoconstriction induced by captopril, making them possible pharmacological targets to prevent or remediate ACEi-induced adverse respiratory reactions.

Isoflurane alone versus small dose propofol with isoflurane for removal of laryngeal mask airway in children-a randomized controlled trial.

To compare the safety of laryngeal mask airway removal using two different deep anaesthesia techniques in paediatric patients. The Randomized Control Trial was conducted at Aga Khan University Hospital, Karachi, from April 2012 to November 2013, and comprised patients aged 2-10 years scheduled for infraumbilical surgeries. Anaesthesia was induced with sevoflurane and later it was maintained by is oflurane, oxygen and nitrous oxide. The laryngeal mask airway was removed in the intervention group-I at 0.4 minimum alveolar concentration of isoflurane with propofol 1mg/kg. In the control group-II, it was removed at 1.2 minimum alveolar concentration of isoflurane alone. SPSS 19 was used for data analysis. Of the 50 patients, there were 25(50%) in each of the two groups. Overall, there were 46(92%) males and 4(8%) females. Incidence of airway obstruction and teeth clenching was significantly higher in group-II (p<0.05 each). Emergence duration was also significantly increased in group-II compared to group-I (p=0.001). The Post-Anaesthesia Care Unit stay timing was not significantly different between the groups (p=0.74). Laryngeal mask airway removal under deep anaesthetic technique of low-dose propofol with isoflurane was found to be associated with minimal adverse airway events than isoflurane alone in paediatric patients.

Are Tracheotomies Required for Patients Undergoing Composite Mandibular Resections for Oral Cancer?

Prophylactic tracheotomy has traditionally been performed during composite mandibular resection of oral cavity cancer to avoid postoperative airway compromise. The purpose of the present study was to measure the frequency and identify the factors associated with an increased or a decreased risk of an adverse airway event (AAE) within 30days postoperatively. A retrospective cohort study of patients who had undergone composite mandibular resection for oral cancer from 2006 to 2018 was conducted at the University of Tennessee Medical Center. The primary predictor variable was composite resection with or without immediate flap reconstruction. The primary outcome variable was realization of a 30-day AAE, defined as the requirement for tracheotomy for any reason, emergent endotracheal reintubation at any time during the postoperative admission, or prolonged (>48hours) postoperative endotracheal intubation. The secondary outcome variable was the inpatient length of stay. Descriptive and bivariate statistics were used to compare the patients with and without an AAE for demographic, confounding, and clinical characteristics. A total of 114 patients were identified through retrospective medical record review. The prevalence of AAEs in the sample was 8.8% (10 of 114). None of the 49 patients without immediate flap reconstruction developed an AAE. Of the 65 patients who had undergone flap reconstruction, 10 (15.4%) developed an AAE. The χ2 analysis revealed a significantly greater rate of AAEs when flap reconstruction was implemented (P<.05). Also, a significantly greater rate of AAEs was found in the group requiring resection of the floor of the mouth with bilateral neck dissections and immediate flap reconstruction compared with all other flap reconstruction groups (P<.05). A composite resection involving the floor of the mouth with bilateral neck dissection and flap reconstruction should receive strong consideration for prophylactic tracheotomy to avoid an AAE.

Pediatric airway management in undiagnosed congenital subglottic stenosis patients

Pediatric unanticipated difficult airway in cases of subglottic stenosis (SGS) is always a challenge. We present two cases of SGS which were managed according to the pediatric difficult intubation protocols where supraglottic device was used as secondary intubation plan successfully. Airway management in these cases depends on the urgency of the surgery; if the surgery is nonemergent, the case can be postponed and both surgical and nonsurgical modalities of treatment can be offered; however, in wake of emergency surgery, surgical airway is indicated. Strategies of the pediatric airway management have evolved over the years, but the risk and morbidity associated with the adverse airway events loom larger.

Classic laryngeal mask airway insertion with laryngoscope mcgrath and macintosh: A case series

Laryngeal mask airway (LMA) is often performed for airway management. Correct placement of LMA can prevent severe leaks and even obstruction of the airway. Insertion under laryngoscope guidance has been used to achieve the ideal positioning of the LMA. Efficacy of LMA insertion by laryngoscope can be evaluated with cheap, safe, and easy to use method. This case series evaluates LMA insertion with McGrath video laryngoscope and Macintosh laryngoscope. We use 20 cases to evaluate oropharyngeal leak pressure, time taken for insertion, hemodynamic after insertion, first attempt insertion, ease of insertion, and adverse airway event after LMA insertion.

Airway management in the critically ill patient - How can we improve?

Introduction The NAP4 demonstrated adverse airway outcomes are associated with poor airway assessment and poor planning. 25% of major airway events occur in the Intensive Care Unit (ICU) or emergency department (ED), and the outcome of these events are more likely to lead to permanent harm or death compared with the operating theatre. This study set out to review documentation of intubations in ICU patients, including the pre-procedure planning taking place to identify areas for improvement. Methods Single institution retrospective review of documentation of endotracheal intubations performed by ICU staff (on either ICU or a ward/ED) over a six week period in an English district general teaching hospital. Criteria assessed were: use of a pre-intubation checklist, documentation of name and grade of intubator, airway assessment, time of intubation, drugs and doses given, number of attempts at intubation, use of cricoid pressure, laryngoscopy grade, ETT size + length at teeth, type of laryngoscope used, monitoring used (including etCO2), ventilator settings and any complications. Results In the 6 week study period, there were 15 intubation episodes identified and reviewed (12 on ICU, 3 in ED). See attached table for full results. Discussion The lowest performing domain was airway assessment (0%). The explanation for this is likely in part due to the acutely unwell nature of ICU patients making airway assessment more challenging than in an elective setting. Another particularly low scoring domain was the use of a pre-procedure checklist (33%). Considering the NAP findings associating adverse airway events with poor airway assessment and planning, these are concerning findings, and unlikely to be isolated to this hospital. We suggested education to promote the routine use of a pre-intubation checklist that incorporates an airway assessment and procedural plan.

Airway rescue during sedation: a proposed airway rescue pathway for nonanesthesiologists.

This review summarizes key features of adverse airway and respiratory events for which sedation providers must be prepared to diagnose and treat in a timely manner. Key features include elements of the presedation patient evaluation that predict adverse airway and respiratory events; patient profiles, target sedation levels, and procedure types that should prompt a consult with an anesthesiologist; necessary clinical skills, essential equipment, and reversal drugs necessary to manage adverse airway and respiratory events; and a proposed airway rescue pathway that describes a sequence of interventions and prompts to call for help when encountering an adverse airway or respiratory event. Several studies have reported adverse events from sedation. Although the overall rate can approach 4.5%, the incidence of events associated with severe harm is low (e.g., <0.5%). Some that are most harmful are prolonged ventilatory compromise leading to hypoxic brain injury or death. Inadequate clinical skills that contribute to these poor outcomes include undetected or delayed detection of hypopnea, apnea, and partial or complete airway obstruction, inadequate rescue skills to manage drug-induced ventilatory depression or airway obstruction, and/or a delay or no attempt to call for expert help followed by a timely response and intervention from that expert help. To improve outcomes in detecting and managing adverse airway and respiratory events, nonanesthesiologists sedation practitioners must be trained in patient selection, monitoring, pharmacology, physiology, and airway management. One gap in sedation training curriculum is a roadmap to use when managing an adverse airway or respiratory events. This review puts forth a suggested airway rescue pathway for nonanesthesiologist sedation practitioners to use as a decision aid during an adverse airway or respiratory event associated with procedural sedation.

Safety and Dose Study of Targeted Lung Denervation in Moderate/Severe COPD Patients

Rationale: Targeted lung denervation (TLD) is a novel bronchoscopic treatment for the disruption of parasympathetic innervation of the lungs. Objectives: To assess safety, feasibility, and dosing of TLD in patients with moderate to severe COPD using a novel device design. Methods: Thirty patients with COPD (forced expiratory volume in 1 s 30–60%) were 1:1 randomized in a double-blinded fashion to receive TLD with either 29 or 32 W. Primary endpoint was the rate of TLD-associated adverse airway effects that required treatment through 3 months. Assessments of lung function, quality of life, dyspnea, and exercise capacity were performed at baseline and 1-year follow-up. An additional 16 patients were enrolled in an open-label confirmation phase study to confirm safety improvements after procedural enhancements following gastrointestinal adverse events during the randomized part of the trial. Results: Procedural success, defined as device success without an in-hospital serious adverse event, was 96.7% (29/30). The rate of TLD-associated adverse airway effects requiring intervention was 3/15 in the 32 W versus 1/15 in the 29 W group, p = 0.6. Five patients early in the randomized phase experienced serious gastric events. The study was stopped and procedural changes made that reduced both gastrointestinal and airway events in the subsequent phase of the randomized trial and follow-up confirmation study. Improvements in lung function and quality of life were observed compared to baseline values for both doses but were not statistically different. Conclusions: The results demonstrate acceptable safety and feasibility of TLD in patients with COPD, with improvements in adverse event rates after procedural enhancements.

Conditions for laryngeal mask airway placement in terms of oropharyngeal leak pressure: a comparison between blind insertion and laryngoscope-guided insertion

BackgroundInsertion under laryngoscopic guidance has been used to achieve ideal positioning of the laryngeal mask airway (LMA). However, to date, the efficacy of this technique has been evaluated only using fiberoptic evaluation, and the results have been conflicting. Other reliable tests to evaluate the efficacy of this technique have not been established. Recently, it has been suggested that the accuracy of LMA placement can be determined by clinical signs such as oropharyngeal leak pressure (OPLP). The aim of this study was to assess the efficacy of LMA insertion under laryngoscopic guidance using OPLP as an indicator.MethodsAfter approved by the institutional ethics committee, a prospective comparison of 100 patients divided into 2 groups (50 with blind technique and 50 with the laryngoscope technique) were evaluated. An LMA (LarySeal™, Flexicare medical Ltd., UK) was inserted using the blind approach in the blind insertion group and using laryngoscopy in the laryngoscope-guided insertion group. The OPLP, fiberoptic position score, whether the first attempt at LMA insertion was successful, time taken for insertion, ease of LMA insertion, and adverse airway events were recorded.ResultsData were presented as mean ± standard deviation. The OPLP was higher in the laryngoscope-guided insertion group than in the blind insertion group (21.4 ± 8.6 cmH2O vs. 18.1 ± 6.1 cmH2O, p = 0.031). The fiberoptic position score, rate of success in the first attempt, ease of insertion, and pharyngolaryngeal adverse events were similar between both groups. The time taken for insertion of the LMA was significantly longer in the laryngoscope-guided insertion group, compared to blind insertion group (35.9 ± 9.5 s vs. 28.7 ± 9.5 s, p < 0.0001).ConclusionLaryngoscope-guided insertion of LMA improves the airway seal pressure compared to blind insertion. Our result suggests that it may be a useful technique for LMA insertion.Trial registrationcris.nih.go.kr, identifier: KCT0001945 (2016-06-17).

Isoflurane alone versus small dose propofol with isoflurane for removal of laryngeal mask airway in children-randomized controlled trial

To compare the safety of laryngeal mask airway removal using two different deep anaesthesia techniques in paediatric patients.The Randomized Control Trial was conducted at Aga Khan University Hospital, Karachi, from April 2012 to November 2013, and comprised patients aged 2-10 years scheduled for infraumbilical surgeries. Anaesthesia was induced with sevoflurane and later it was maintained by is oflurane, oxygen and nitrous oxide. The laryngeal mask airway was removed in the intervention group-I at 0.4 minimum alveolar concentration of isoflurane with propofol 1mg/kg. In the control group-II, it was removed at 1.2 minimum alveolar concentration of isoflurane alone. SPSS 19 was used for data analysis.Of the 50 patients, there were 25(50%) in each of the two groups. Overall, there were 46(92%) males and 4(8%) females. Incidence of airway obstruction and teeth clenching was significantly higher in group-II (p<0.05 each). Emergence duration was also significantly increased in group-II compared to group-I (p=0.001). The Post-Anaesthesia Care Unit stay timing was not significantly different between the groups (p=0.74).Laryngeal mask airway removal under deep anaesthetic technique of low-dose propofol with isoflurane was found to be associated with minimal adverse airway events than isoflurane alone in paediatric patients.