Airway Intubation Research Articles

Successful endotracheal intubation for difficult airway using a protruding malleable stylet

Successful endotracheal intubation for difficult airway using a protruding malleable stylet

Association between multiple intubation attempts and complications during emergency department airway management: A national emergency airway registry study

ObjectivePeri-intubation complications are important sequelae of airway management in the emergency department (ED). Our objective was to quantify the increased risk of complications with multiple attempts at emergency airway intubation in the ED. MethodsThis is a secondary analysis of a prospectively collected multicenter registry (National Emergency Airway Registry) consisting of attempted ED intubations among subjects aged >14 years. The primary exposure variable was the number of intubation attempts. The primary outcome measure was the occurrence of peri-intubation major complications within 15 min of intubation including hypotension, hypoxemia, vomiting, dysrhythmias, cardiac arrest, esophageal intubation, and failed airway with cricothyrotomy. We constructed multivariable logistic regression models to determine the associations between complications and the number of intubation attempts while controlling for measured pre-exposure variables. ResultsThere were 19,071 intubations in the NEAR database, of which 15,079 met inclusion for this analysis. Of these, 13,459 were successfully intubated on the first attempt, 1,268 on the second attempt, 269 on the third attempt, 61 on the fourth attempt, and 22 on the fifth or more attempt. A complication occurred in 2,137 encounters (14 %). Major complications accompanied 1,968 encounters (13 %) whereas minor complications affected 315 encounters (2 %). The most common major complication was hypoxia. In our multivariable logistic regression model, odds ratios with 95 % confidence intervals for the occurrence of major complications for multiple attempts compared to first-pass success were 4.4 (3.6–5.3), 7.4 (5.0–10.7), 13.9 (5.6–34.3), and 9.3 (2.1–41.7) for attempts 2–5+ (reference attempt 1), respectively. ConclusionsWe found an independent association between the number of intubation attempts among ED patients undergoing emergency airway intubation and the risk of complications.

The use of a FROVA airway intubation introducer as a guide before nasotracheal intubation could improve insertion condition

BackgroundNumerous complications are related to nasal intubation. ObjectiveThis study compared the efficacy of the FROVA catheter-guided technique to the conventional blind approach in reducing epistaxis occurrences and improving nasal airway provision. We hypothesized that compared with the conventional approach, using the FROVA catheter would have a 30 % higher incidence of successful intubation without epistaxis. MethodsThis was a randomized trial conducted under single-blind conditions. Only asymptomatic patients with easy nasal breathing who underwent maxillofacial surgery with nasotracheal intubation, aged 18 to 65, and had ASA I and II physical status were involved. Patients were allocated into the conventional (n = 50) and FROVA groups (n = 50). ResultsAll patients had successful tracheal tube insertions through the chosen nostril. Patient demographics and preop evaluations were similar. The FROVA-guided method was superior to the conventional method regarding the incidence of epistaxis after nasotracheal intubation. The FROVA group exhibited a substantially reduced incidence of epistaxis, with an absolute risk reduction of 52 % (95 % confidence interval: 36.18–67.82; P-value <0.001) and required fewer manipulations (p < 0.001). Also, less epistaxis severity through intubation was reported in the FROVA group (p < 0.001). The FROVA group had a higher incidence of tracheal tubes in the lower nasal passage (p < 0.001). ConclusionsGuiding the tracheal tube through the nasal cavity using a FROVA catheter has improved insertion conditions and reduced the severity and occurrence of epistaxis.

Laryngeal Mask Airway vs. Orotracheal Intubation: A Review of Safety and Efficacy in Elective Procedures

Laryngeal Mask Airway vs. Orotracheal Intubation: A Review of Safety and Efficacy in Elective Procedures

Airway management and pulmonary aspiration during surgical interventions in pregnant women in the 2nd/3rd trimester and immediate postpartum – a retrospective study in a tertiary care university hospital

BackgroundPregnancy is associated with an increased risk of pulmonary aspiration during general anaesthesia, but the incidence of this complication is not well defined.MethodsWe performed a retrospective database review in a tertiary care university hospital to determine the incidence of pulmonary aspiration in pregnant patients undergoing endotracheal intubation, with and without Rapid Sequence Induction (RSI), as well as face-mask ventilation and supraglottic airway devices. We included Patients in the 2nd or 3rd trimester of pregnancy and immediate postpartum undergoing surgical procedures. The primary endpoint was the occurrence of pulmonary aspiration.ResultsData from 2,390 patients undergoing general anaesthesia for cerclage of cervix uteri, manual removal of retained placenta, repair of obstetric laceration, or postpartum bleeding were retrospectively evaluated. A supraglottic airway device or face-mask ventilation was used in 1,425/2,390 (60%) of patients, while 638/2,390 (27%) were intubated. RSI was used in 522/638 (82%) of patients undergoing tracheal intubation, or 522/2,390 (22%) of the entire cohort. In-depth review of the charts, including 54 patients who had been initially classified as “possible pulmonary aspiration" by anaesthetists, revealed that this adverse event did not occur in the cohort.ConclusionsIn conclusion, in this obstetric surgery patient population at risk for pulmonary aspiration, supraglottic airway devices were used in approximately 60% of cases. Yet, no aspiration event was detected with either a supraglottic airway or endotracheal intubation.

Neonatal Outcomes Are Similar between Patients with Resolved and Those with Persistent Oligohydramnios.

Oligohydramnios (defined as amniotic fluid volume < 5 cm or deepest vertical pocket < 2 cm) is regarded as an ominous finding on prenatal ultrasound. Amniotic fluid, however, is not static, and to date, there have been no studies comparing perinatal outcomes in patients who are diagnosed with oligohydramnios that resolves and those who have persistent oligohydramnios. This is a secondary analysis of a National Institutes of Health-funded retrospective cohort study of singleton gestations delivered at a tertiary care hospital between 2002 and 2013 with mild hypertensive disorders and/or fetal growth restriction (FGR). Maternal characteristics, delivery, and neonatal information were abstracted by trained research nurses. Patients with a diagnosis of oligohydramnios were identified, and those with resolved versus persistent oligohydramnios at the time of delivery were compared. The primary outcome was a composite of neonatal resuscitation at delivery: administration of oxygen, bag-mask ventilation, continuous positive airway pressure, intubation, chest compression, or cardiac medication administration. Secondary outcomes included FGR, timing, and mode of delivery. Of 527 women meeting study criteria, 42 had oligohydramnios that resolved prior to delivery, whereas 485 had persistent oligohydramnios. There were no significant differences in patient demographics between groups. The gestational age at diagnosis was significantly lower for patients with resolved versus persistent oligohydramnios (median: 33.0 [interquartile range, IQR: 29.1-35.9] vs. 38.0 [IQR: 36.4-39.3], p < 0.001). There was not a substantial difference in rate of neonatal resuscitation (41 vs. 32%, p = 0.31). Patients with resolved oligohydramnios were more likely to have developed FGR than those with persistent oligohydramnios (55 vs. 36%, p < 0.02). There were no significant differences for gestational age at delivery, birth weight, or neonatal intensive care unit admission. Patients whose oligohydramnios resolved were diagnosed earlier yet had similar rates of neonatal resuscitation but higher rates of FGR than those who had persistent oligohydramnios. · When diagnosed earlier in pregnancy, oligohydramnios was more likely to resolve prenatally.. · Patients who were diagnosed with oligohydramnios earlier in pregnancy had higher rates of FGR.. · There were no differences in the rates of the composite outcome of need for neonatal resuscitation when comparing those with resolved versus those with persistent oligohydramnios. No differences in composite neonatal morbidity were noted between those with resolved versus persistent oligohydramnios..

Current trends in emergency airway management: a clinical review.

Airway management is a fundamental and complex process that involves a sequence of integrated tasks. Situations requiring emergency airway management may occur in the emergency department, intensive care units, and various other clinical spaces. A variety of challenges can arise during emergency airway preparation, intubation, and postintubation, which may result in significant complications for patients. Therefore, many countries are establishing step-by-step systemization and detailed guidelines and/or updating their content based on the latest research. This clinical review introduces the current trends in emergency airway management, such as emergency airway management algorithms, comparison of video and direct laryngoscopy, rapid sequence intubation, pediatric airway management, prehospital airway management, surgical airway management, and airway management education.

Reliable prediction of difficult airway for tracheal intubation from patient preoperative photographs by machine learning methods

BackgroundEstimating the risk of a difficult tracheal intubation should help clinicians in better anaesthesia planning, to maximize patient safety. Routine bedside screenings suffer from low sensitivity. ObjectiveTo develop and evaluate machine learning (ML) and deep learning (DL) algorithms for the reliable prediction of intubation risk, using information about airway morphology. MethodsObservational, prospective cohort study enrolling n=623 patients who underwent tracheal intubation: 53/623 difficult cases (prevalence 8.51%).First, we used our previously validated deep convolutional neural network (DCNN) to extract 2D image coordinates for 27 + 13 relevant anatomical landmarks in two preoperative photos (frontal and lateral views). Here we propose a method to determine the 3D pose of the camera with respect to the patient and to obtain the 3D world coordinates of these landmarks. Then we compute a novel set of dM=59 morphological features (distances, areas, angles and ratios), engineered with our anaesthesiologists to characterize each individual's airway anatomy towards prediction.Subsequently, here we propose four ad hoc ML pipelines for difficult intubation prognosis, each with four stages: feature scaling, imputation, resampling for imbalanced learning, and binary classification (Logistic Regression, Support Vector Machines, Random Forests and eXtreme Gradient Boosting). These compound ML pipelines were fed with the dM=59 morphological features, alongside dD=7 demographic variables. Here we trained them with automatic hyperparameter tuning (Bayesian search) and probability calibration (Platt scaling). In addition, we developed an ad hoc multi-input DCNN to estimate the intubation risk directly from each pair of photographs, i.e. without any intermediate morphological description.Performance was evaluated using optimal Bayesian decision theory. It was compared against experts' judgement and against state-of-the-art methods (three clinical formulae, four ML, four DL models). ResultsOur four ad hoc ML pipelines with engineered morphological features achieved similar discrimination capabilities: median AUCs between 0.746 and 0.766. They significantly outperformed both expert judgement and all state-of-the-art methods (highest AUC at 0.716). Conversely, our multi-input DCNN yielded low performance due to overfitting. This same behaviour occurred for the state-of-the-art DL algorithms. Overall, the best method was our XGB pipeline, with the fewest false negatives at the optimal Bayesian decision threshold. ConclusionsWe proposed and validated ML models to assist clinicians in anaesthesia planning, providing a reliable calibrated estimate of airway intubation risk, which outperformed expert assessments and state-of-the-art methods. Our novel set of engineered features succeeded in providing informative descriptions for prognosis.

The Use of Bi-Nasal Prongs for Delivery of Non-Invasive Ventilation to Foals.

Non-invasive ventilation (NIV) is a method of providing respiratory support without the need for airway intubation. The current study was undertaken to assess tolerance to bi-nasal prongs and NIV in healthy, standing, lightly sedated foals. Bi-nasal prongs were well tolerated by foals, remaining in place for the allocated five minutes in four of six unsedated foals and, subsequently, in five of six lightly sedated foals. All foals tolerated NIV through bi-nasal prongs, although increasing airway pressures were associated with increases in inspiratory volume, duration of inspiration and air leakage in most foals. These changes preceded discontinuation/intolerance of NIV on the basis of behaviour changes consistent with discomfort. Increased circuit leakage was associated with reduced return of expired air to the ventilator and increasing disparity between inspiratory and expiratory times and tidal volumes. The study results suggest that bi-nasal prongs might be suitable for NIV but that design or fitting requires further optimization and that behaviour and ventilator variables should be monitored to assess patient tolerance of the procedure.

The Role of Early Intubation in Status Epilepticus with Out-of-Hospital Onset: A Large Prospective Observational Study.

Background: this study aimed to evaluate the role of early airway management and intubation in status epilepticus (SE) with out-of-hospital onset. Methods: We included all patients with out-of-hospital SE onset referred to the emergency department of the Academic Hospital of Modena between 2013 and 2021. Patients were compared according to out-of-hospital airway management (intubation versus non-intubation) and a propensity score was performed for clinical variables unevenly distributed between the two groups. Results: We evaluated 711 patients with SE. A total of 397 patients with out-of-hospital SE onset were eventually included; of these, 20.4% (81/397) were intubated before arrival at the hospital. No difference was found in the clinical characteristics of patients after propensity score matching. The 30-day mortality in the propensity group was 19.4% (14/72), and no difference was found between intubated (7/36, 19.4%) and non-intubated (7/36, 19.4%) patients. No difference was found in SE cessation. Compared to non-intubated patients, those who underwent out-of-hospital intubation had a higher risk of progression to refractory or super-refractory SE, greater worsening of mRS values between hospital discharge and admission, and lower probability of returning to baseline condition at 30 days after SE onset. Conclusions: Early intubation for out-of-hospital SE onset is not associated with improved patient survival even after balancing for possible confounders. Further studies should evaluate the timing of intubation and its association with first-line treatments for SE and their efficacy. In addition, they should focus on the settings and the exact reasons leading to intubation to better inform early management of SE with out-of-hospital onset.

Laryngeal mask airway versus endotracheal intubation as general anesthesia airway managements for atrial fibrillation catheter ablation: a comparative analysis based on propensity score matching.

The current evidence on the use of laryngeal mask airway (LMA) as an airway management technique for general anesthesia (GA) during atrial fibrillation (AF) catheter ablation (CA) is insufficient. This study aims to compare the feasibility, safety, and clinical benefits of LMA and endotracheal intubation (ETI) for airway management in AF CA. One hundred fifty-two consecutive patients with AF who underwent CA under GA were included and divided into two groups based on different airway management methods (66 in the LMA group, 86 in the ETI group). After propensity score matching, a final analysis cohort of 132 patients was obtained to compare procedural parameters, adverse events, and prognosis between the two groups. The LMA group exhibited significantly shorter total procedural time (p = 0.039), anesthesia induction time (p = 0.015), and recovery time (p = 0.006) compared to the ETI group. The mean arterial pressure (MAP) and heart rate were significantly lower in the LMA group during extubation and 1-min post-extubation (p < 0.05). Furthermore, the LMA group demonstrated lower MAP levels during intubation (p = 0.029). The incidences of intraoperative hypotension (p = 0.017) and bradycardia (p = 0.032) were significantly lower in the LMA group. The incidences of delayed recovery or delirium (p = 0.027), laryngeal or airway injury (p = 0.016), cough or bucking (p = 0.001), and sore throat (p < 0.001) were significantly lower in the LMA group. There were no statistically significant differences in catheter stability parameters and sinus rhythm maintenance rates between the two groups (p > 0.05). LMA is feasible, safe, and effective in AF CA as an optimized airway management technique for GA.

Acute and definitive management of oropharyngeal hemorrhage in patients with squamous cell carcinoma of the oropharynx.

Massive oropharyngeal bleeding post-chemoradiotherapy is a life-threatening condition that requires emergent management. This retrospective case series included 11 patients with oropharyngeal squamous cell carcinoma who suffered from massive bleeding during or following treatment with definitive chemoradiotherapy. Details of acute and definitive management of oropharyngeal bleeding are reported. Nine of 11 hemorrhagic events occurred a mean (SD) of 88.6 days (53.6) after radiotherapy. Airway intubation and embolization were performed in 10 of 11 patients, followed by surgery in 7 of 11 patients. The most commonly embolized vessels were the external carotid and lingual arteries. At the time of discharge, 3 of 11 patients had a tracheostomy, and 7 of 11 continued to use a gastrostomy tube. Four patients died. Hemorrhagic complications in oropharyngeal cancer treatment require emergent responses. Developing a workflow for coordination between multidisciplinary teams can maximize probability of survival and decrease morbidity.

Life-threatening upper gastrointestinal hemorrhage from a Cameron ulcer

Introduction: Acute upper gastrointestinal bleeding can be life-threatening; however, Cameron lesions are an uncommon etiology. These lesions should be suspected with a previous history or endoscopic evidence of hiatus hernia. Case Report: A male in his 60s presented to the emergency department with hematemesis and melena for two days. He had no prior medical, surgical, or endoscopic history and took no regular medications. He was resuscitated with packed red blood cell transfusion and treated with proton pump inhibitor infusion then transferred to operating theaters for endoscopic hemostasis. Cardiac arrest occurred after anesthetic induction and airway intubation, return of spontaneous circulation was achieved after cardiopulmonary resuscitation and further blood transfusion. At endoscopy a Cameron ulcer was noted in the hiatus hernia with overlying blood clot with no active hemorrhage, treated with Hemospray®. Conclusion: Patients presenting with acute upper gastrointestinal hemorrhage and shock need urgent upper gastrointestinal (UGI) endoscopy. Topical hemostatic agents are successful in controlling bleeding when challenging anatomy precludes use of banding or clip application.

Attenuation of the hemodynamic response to laryngoscopy and tracheal intubation: A randomized controlled trial

Background: Fentanyl and lidocaine are two drugs that are often suggested to lower the reaction of the blood flow to laryngoscopy and endotracheal intubation. Aims and Objectives: The main goal of our study is to find out how the heart and blood vessels react when laryngoscopy and intubation are used. A comparison was made between fentanyl 2 mcg/kg and fentanyl 2 mcg/kg plus 15 mg of paracetamol per kg of body weight. The goal was to find the best and safest ways for these options to reduce stress during laryngoscopy and intubation. Materials and Methods: The anesthesiology department and the general surgery department at the medical college and hospital that is connected to it worked together on the study. The study included a total of 120 patients, covering a wide age range from 20 to 70 years, and including both males and females. The patients had physical statuses I and II, indicating their overall health. In Group A, patients were given a pre-medication of 0.02 mg/kg of glycopyrrolate and then 2 mg/kg of fentanyl through an intravenous (IV) 90 s before they were intubated. Fentanyl at a dose of 2 mcg/kg was given to patients in Group B 90 s before they were intubated. A dose of 15 mg/kg of paracetamol was also given 10 min before the operation. As a starting point, the medical team wrote down the patient’s heart rate (HR), systolic and diastolic blood pressures, and mean artery pressure before they started intubation. Results: Large rise in HR was seen in Group A, while Group B’s HR stayed close to the baseline. There was a clear rise in mean blood pressure in both groups after intubation. Group A, on the other hand, saw a rise that was clear and lasted for 6 min, while Group B did not. When compared to IV fentanyl alone, IV fentanyl and paracetamol work better at lowering the changes in blood flow that happen during laryngoscopy and airway intubation. Conclusion: This finding highlights the potential benefits of combining these two medications for improved patient outcomes. Endotracheal intubation, fentanyl, paracetamol, and laryngoscopy are all important medical terms that are commonly used in health-care settings. These procedures and medications play a crucial role in various medical interventions and treatments. Understanding the significance and proper usage of these terms is essential for health-care professionals to provide effective care to their patients.

Can Laryngeal Mask Airway be the First Choice for Tracheal Stenosis Surgery? A Historical Cohort Study.

To compare the usage of laryngeal mask airway (LMA) and orotracheal intubation (OTI), which are separate airway management methods in tracheal reconstruction surgeries, in terms of perioperative management, mortality, and morbidity. Adult patients who underwent tracheal reconstruction surgery between June 2020 and June 2022 were included in the study, retrospectively. Patients with lost data or primary tracheal malignancy were excluded. Patients who underwent tracheal reconstruction were divided into two groups: LMA and OTI. Of a total of 57 included patients, the OTI and LMA groups had 30 (52.63%) and 27 patients (47.37%), respectively. The rate of intubated transfer to the intensive care unit and the length of stay in the intensive care unit were significantly higher in the OTI group (p=0. 014, p=0. 031) than those of the LMA group; further, in tracheal cultures, reproduction was also significantly higher in the OTI group (23.33%) (p=0. 007). The postoperative mortality rates were similar in both groups. Since the absence of tension in end-to-end anastomosis of the trachea is vital for successful surgery, the LMA application (which has no tracheal contact) can be considered superior to OTI. In this study, LMA was successfully applied in all patients. Considering that the aim of anesthesia management should be to provide adequate oxygenation and normocarbia with minimally invasive intervention, we suggest airway management using LMA as the first option for tracheal reconstruction surgery because of the advantages described in this study.

Lifesaving Maneuver In Full Airway Obstruction Caused By Foreign Body Aspiration: Pushing The Foreign Body To The Right Main Bronchus

Foreign body aspiration (FBA) is one of the leading causes of accidental death in children. Patients with severe respiratory failure and upper airway obstruction who need resuscitation due to FBA apply to emergency services. In this case report, we present a 22-month-old male patient who applied to the pediatric emergency department due to foreign body aspiration, and whose saturation value increased by providing unilateral lung ventilation by pushing the foreign body from the trachea into the bronchi during intubation for advanced airway

Factors Affecting Holmium Laser Efficiency: Comparison of Laryngeal Mask Airway and Endotracheal Intubation During Ureteroscopy for Renal Stones.

Introduction: Holmium laser lithotripsy is a standard energy source used for treatment of kidney stones during flexible ureteroscopy. Efficiency of laser surgery may be affected by patient and operator characteristics or perioperative management. Here, we sought to examine intraoperative data from patients undergoing high frequency dusting with high-powered holmium laser lithotripsy to evaluate surgical and demographic factors associated with lasing efficiency (LE). Methods: A total of 82 intraoperative reports were analyzed from an ongoing laser lithotripsy clinical trial evaluating the Lumenis Pulse™ 120H holmium laser with renal stones up to 20 mm in diameter with and without Moses 2.0 technology. For each case, the total pause time between lasing activations was corrected to remove lengthy pauses and divided by the total lasing time to calculate an efficiency percentage. This was then compared with patient demographics, anesthesia administration, stone burden, postoperative complications, and stone-free rates using both univariate and multivariate analyses. Results: Of the 82 included patients, 36 received endotracheal tube (ETT) intubation and 46 had a laryngeal mask airway (LMA). Patients with ETT had significantly higher LE (78.7%) compared to those with an LMA (73.3%) in our univariate analysis (p < 0.01) as well as in the multivariate model that adjusted for maximum stone size, number of stones, stone density, and patient body mass index (p < 0.05). There was also significantly higher mean LE in patients with no postoperative complications (76.3%) compared to those with any grade (I-V) Clavien-Dindo complication within 30 days after surgery (70.0%) (p < 0.05). Conclusions: Flexible ureteroscopy and laser lithotripsy cases with higher LE are associated with lower rates of postoperative complications. The data also support the use of ETT over LMA to improve overall LE; however, this remains one consideration among many for choosing anesthesia administration. Clinical Trial Registration number: NCT04505956.

Abstract 327: Implementation of Bronchoalveolar Lavages as a Quality Improvement Initiative in Out-of-Hospital Cardiac Arrest Patients

Patients who suffer OHCA are at risk for early onset pneumonia due to loss of airway protection, emergency airway access and intubation, CPR, mechanical ventilation, among other complications. It is difficult to accurately diagnose early onset pneumonia post OHCA due to multi-organ dysfunction post arrest and radiography findings confounded by non-infectious inflammation from CPR and aspiration. As a result, a substantial number of patients receive empiric antibiotics. A bronchoalveolar lavage (BAL) can screen for the presence of bacteria in the lungs and aid in identifying the incidence of early onset pneumonia after OHCA. We implemented a quality improvement (QI) initiative to collect a BAL on initial patient presentation to our hospital in May 2018. We conducted an observational, retrospective study to assess the impact of BAL implementation on empiric antibiotic prescribing. We used a rigorous study definition of pneumonia requiring at least two of the following positive within the same 24-hour period: BAL, chest radiography, and/or a fever &gt;38°C. We compared rates of antibiotic prescription in the first 7 days of hospitalization for patients receiving a BAL to those without, as well as rates of antibiotic prescriptions before and after implementation of the BAL QI initiative. Implementation of initial BAL collection was successful and resulted in a 66% increase of BALs (from 44 to 73 BALs) collected compared to an average from the prior 2 years. We hypothesized rates of antibiotic prescription would decrease post-implementation of BAL collection; however, there was no statistically significant change in rate of antibiotic prescription (Figure 1) over the initial 7-day hospitalization period X 2 ( Df = 1, N = 3247) = 0.68, p = 0.54. Over 80% of patients with pneumonia received antibiotics, roughly 60% of OHCA patients received antibiotics despite no pneumonia diagnosis by any definition. Further study is needed to alter these practices and reduce antibiotic overuse.

Evolution of the concepts of pediatric airway and endotracheal intubation

The tenets of airway anatomy and management continue to be reevaluated and challenged as our knowledge increases. This has led to a better understanding of the pediatric airway and its critical differences from adults. This evolving understanding of the pediatric airway size and shape has significant clinical implications to airway management in the operating room, emergency department, and the intensive care unit. The first significant change in clinical practice was the transition to the routine use of cuffed endotracheal tubes (ETTs). This was facilitated by the availability of the Microcuff® with a polyurethane cuff and a redesigned position of the cuff on the shaft of the ETT without the Murphy’s eye. Additional attention to the design and the location of the cuff on the ETT may be necessary as well as to markings for depth of intubation on the shaft of the ETT to ensure that the cuff is placed fully below the cricoid ring following endotracheal intubation. Inflation of the cuff with high intracuff pressures within the cricoid ring may compromise perfusion of the tracheal mucosa and result in airway injury.

Diagnostic accuracy of using capnography in verification of nasogastric tube placement among adult patients in hospital settings: Protocol of a diagnostic study.

To determine the diagnostic accuracy of end-tidal carbon dioxide (ETCO2) detection using capnography for verifying the correct placement of nasogastric tubes (NGTs) among adult patients in hospital settings. A prospective observational diagnostic study will be conducted. Patients ≥ 18-year-old and requiring the insertion of an NGT will be recruited using a convenience sampling method from 39 general medical and geriatric wards, intensive care units, accident and emergency departments, and subacute/rehabilitation/infirmary wards in 21 acute or subacute/convalescent/extended care hospitals. ETCO2 detection by sidestream capnography, which indicates an airway intubation of an NGT when a capnogram waveform or an ETCO2 level > 10mmHg (1.33 kPa) occurs, will serve as the index test. The reference standards will be the X-ray performed and pH value of gastric aspiration (pH ≤ 5.5) after the index test. Each participant will be included only once. Sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve of capnography will be calculated to assess the diagnostic performance of capnography. The variability in diagnostic accuracy in participants with different characteristics will be explored by using chi-squared or Fisher's exact tests. The time spent and the cost of the tests will be compared using the paired t-test. All statistical tests will be two-sided with a level of significance set at 0.05. This study will provide evidence on the diagnostic accuracy of capnography in verifying NGT placement and its applicability to patients in hospitals settings, since this evidence is limited in the current literature. In addition, it will help identify the optimal combination of tests in verifying the correct placement of NGTs and inform the update of clinical practice guidelines and stakeholders' decisions on the adoption of ETCO2 detection as a routine method for verifying NGT placement. ClinicalTrials.gov ID: NCT05817864.