The nasopharyngeal airway: dispelling myths and establishing the facts

Effects of saline submersion at body temperature on airway supportive devices including a novel nasopharyngeal device produced using 3D-printing

PURPOSE

This study investigated dimension changes of various nasopharyngeal airways, including a novel self-supporting device, after saline submersion at body temperature to simulate in-vivo use. Dimension changes over time may reduce efficacy during long-term use and require sizing adjustments or limits on duration of use.

MATERIALS AND METHODS

Cuffless Covidien endotracheal tubes, pediatric Rusch fixed flange polyvinyl chloride nasal airway tubes, pediatric Rusch Robertazzi style Mediprene nasal airway tubes, and novel silicone elastomer self-supporting nasopharyngeal airways were fully submerged in 0.9 % normal saline solution incubated at 37 degrees Celsius for 15 days. All devices had tube length and wall thickness measured after 0, 1, 2, 3, 4, 5, 10, and 15 days. The 95 % confidence intervals of tube dimensions at each date were compared with the 95 % confidence intervals at day 0.

RESULTS

The Covidien ET tube, Rusch PVC NPA, and ssNPA tube lengths and wall thicknesses did not change significantly over 15 days. The Rusch Mediprene NPAs had a statistically significant increase in length starting at day 1 and wall thickness at day 2.

CONCLUSIONS

The novel ssNPA did not expand in the in-vitro environment, supporting its safety for extended use. The PVC NPA and ET tube dimensions also remained stable. However, the Rusch Mediprene NPAs had significant length expansion after 1 day of submersion, indicating a considerable risk of expansion during extended use with potential implications for patient care. Silicone and PVC NPA dimensions remained stable when saturated, indicating these materials may be more appropriate for extended use.

Introducing the First Distal Pharyngeal Airway

Airway obstruction during anesthesia is a common occurrence with potentially serious outcomes. Increasingly, patients are older, heavier, and more likely to have obstructive sleep apnea-all heightened risk factors for airway complications. These patients undergo procedures where distal pharyngeal tissues can relax, obstructing the airway. As a result, there is a need for airway devices that can stent open distal pharyngeal tissues to maintain adequate ventilation. To physically address this problem, the new distal pharyngeal airway (DPA) prevents airway obstruction and enables providers to maintain ventilation.

Novel treatment for hypotonic airway obstruction and severe obstructive sleep apnea using a nasopharyngeal airway device with 3D printing innovation

STUDY OBJECTIVES

Pediatric obstructive sleep apnea impacts child and familial well-being. Airway management in patients with hypotonic pharyngeal conditions is complex. Some patients may benefit from continuous positive airway pressure or bilevel positive airway pressure, others may require further invasive measures for treatment. There is critical need for treatment alternatives for patients with pharyngeal hypotonia.

METHODS

This is a retrospective case series. Collaboratively with patients, families, biomedical engineers, and medical professionals, a long-term nasopharyngeal airway (NPA) was created to bypass upper airway obstruction. Two patients used a safety pin and tape attachment, and two patients used a novel 3D-printed, self-supporting nasal securement. All 4 patients had polysomnography before and during NPA use. Paired 1-tailed t-tests were conducted to compare apnea-hypopnea index, hypopnea index, obstructive index, and oxygen nadir.

RESULTS

Compared to baseline polysomnography, repeat polysomnography with the NPA in place demonstrated statistically significant improvement for apnea-hypopnea index (75.8 ± 36.6 events/h to 8.9 ± 2.9 events/h, P = .03), hypopnea index (45.4 ± 25.8 events/h to 7.7 ± 3.2 events/h, P = .04), and oxygen saturation nadir (60.3 ± 13.0% to 79.3 ± 8.7%, P = .01). The NPA had been used for over 1 year in 3 of the 4 children. Those using the safety pin and tape did report skin irritation due to adhesive required to keep device in place.

CONCLUSIONS

Current management of severe upper airway obstruction and obstructive sleep apnea in hypotonic pharyngeal conditions requires a team-based approach to care. A long-term NPA device may be an alternative or temporizing option to continuous positive airway pressure, upper airway surgery, or tracheostomy in children with pharyngeal hypotonia and severe obstructive sleep apnea. Larger studies of this approach are underway to assess efficacy in a range of obstructive sleep apnea severity in this population.

CITATION

Powell AR, Srinivasan S, Helman JL, et al. Novel treatment for hypotonic airway obstruction and severe obstructive sleep apnea using a nasopharyngeal airway device with 3D printing innovation. J Clin Sleep Med. 2022;18(10):2497-2502.

Prehospital Manual Ventilation: An NAEMSP Position Statement and Resource Document

Manual ventilation using a self-inflating bag device paired with a facemask (bag-valve-mask, or BVM ventilation) or invasive airway (bag-valve-device, or BVD ventilation) is a fundamental airway management skill for all Emergency Medical Services (EMS) clinicians. Delivery of manual ventilations is challenging. Several strategies and adjunct technologies can increase the effectiveness of manual ventilation. NAEMSP recommends:All EMS clinicians must be proficient in bag-valve-mask ventilation.BVM ventilation should be performed using a two-person technique whenever feasible.EMS clinicians should use available techniques and adjuncts to achieve optimal mask seal, improve airway patency, optimize delivery of the correct rate, tidal volume, and pressure during manual ventilation, and allow continual assessment of manual ventilation effectiveness.

Working with estimation-formulas to predict nasopharyngeal airway insertion depth in children: Looking at magnetic resonance images - A prospective observational study (WEND:LI-Study)

OBJECTIVE

To determine the accuracy of the recently proposed landmark-method 'nostril-to-tragus minus 10 mm' and compare with ERC-recommended distances for nasopharyngeal airway length sizing in children.

METHOD

We conducted a prospective observational study in sedated children < 12 years. Nasopharyngeal airways were inserted following 'nostril-to-tragus minus 10 mm'. Primary outcome was the rate of nasopharyngeal airway tips between soft palate and epiglottis on magnetic resonance imaging (MRI) indicated for medical reasons. An optimal placement was defined when the tip lied within 25-75% of the total soft palate-to-epiglottis distance. Between 0-100% of this distance, placement was still considered acceptable, below 0% too proximal or above 100% too distal. Secondary outcomes were the rate of adverse events, the qualitative positions of airway tips, and the comparison of ́nostril-to-tragus minus 10 mḿ with the ERC-recommended distances 'nostril-to-angle of the mandible' and 'nostril-to-tragus' with objective MRI measurements.

RESULTS

We analysed 92 patients with a mean age of 4.3 years. Nasopharyngeal airways were optimally placed in 37.0% (8.7% too proximal-77.2% acceptable-14.1% too distal). Three qualitative malpositions, but no airway-associated adverse event occurred. Objective measurements on MRI revealed the probability of 40.2% optimally placed nasopharyngeal airways (5.4%-67.4%-27.2%) for 'nostril-to-tragus minus 10 mm', 38.0% (17.4%-58.7%-23.9%) for 'nostril-to-mandible' and 13.0% (0%-28.3%-71.7%) for 'nostril-to-tragus', respectively.

CONCLUSION

No landmark-method predicted nasopharyngeal airway position reliably. 'Nostril-to-tragus minus 10 mm' seems the least inaccurate one and could be a valuable approximation until another estimation-formula proves more accurate. During insertion, careful clinical evaluation of airway patency is crucial.

REGISTERED CLINICAL TRIAL

German Clinical Trials Register; DRKS00021007.

Medical and surgical devices in the emergency and trauma patient: what the radiologist should know, and how they can add value

A variety of different external and internal medical devices are used in the acute setting to maintain life support and manage severely injured and unstable trauma or emergency patients. These devices are inserted into the acutely ill patient with the specific purpose of improving outcome, but misplacement can cause additional morbidity and mortality. Consequently, meaningful interpretation of the position of devices can affect acute management. Some devices such as nasopharyngeal, nasogastric and endotracheal tubes and chest and surgical drains are well known to most clinicians, however, little formal training exists for radiologists in composing their report on the imaging of these devices. The novice radiologist often relies on tips and phrases handed down in an aural tradition or resorts to phrases such as: "position as shown". Furthermore, radiologists with limited experience in trauma might not be familiar with the radiological appearance of other more specific devices. This review will focus on the most common medical devices used in acute trauma patients, indications, radiological appearance and their correct and suboptimal positioning.

Mandibular advancement devices shorten desaturation duration in patients at high risk for obstructive sleep apnea syndrome during intravenous propofol sedation in the decubitus position

BACKGROUND

The purpose of this study was to determine the efficacy of a mandibular advancement device (MAD) for increasing patient safety during sedated total knee arthroplasty (TKA) and total hip replacement (THR).

METHODS

Forty patients undergoing TKA or THR surgery in the supine or lateral recumbent positions under spinal anesthesia were enrolled. Sedation and oxygenation were administered. The MAD (Sweet Sleep Anti-Snoring Device) was then placed after 15 minutes of observation. SpO2, PetCO2, blood pressure, and respiratory rate were recorded.

RESULTS

Sedated patients in the decubitus position had higher saturation nadirs, shorter desaturation durations, shorter airway obstruction durations, and fewer rescue events than those in the supine position. In patients at a high risk of obstructive sleep apnea syndrome (OSAS), desaturation duration, obstruction duration, apnea duration, desaturation duration, and rescue events were significantly lower after MAD placement. However, the saturation nadir did not improve after MAD placement.

CONCLUSION

The MAD may shorten the duration of desaturation events during spontaneous breathing sedative procedures in the lateral recumbent position but not in the supine position. Breathing patterns did not change from nasal breathing to oral breathing or vice versa between pre- and postplacement of the MAD. Sedation score evaluation affects breathing pattern changes from oral breathing to nasal breathing and vice versa.

Oxygenation laryngoscope vs. nasal standard and nasal high flow oxygenation in a technical simulation of apnoeic oxygenation

Background

Failed airway management is the major contributor for anaesthesia-related morbidity and mortality. Cannot-intubate-cannot-ventilate scenarios are the most critical emergency in airway management, and belong to the worst imaginable scenarios in an anaesthetist’s life. In such situations, apnoeic oxygenation might be useful to avoid hypoxaemia. Anaesthesia guidelines recommend careful preoxygenation and application of high flow oxygen in difficult intubation scenarios to prevent episodes of deoxygenation. In this study, we evaluated the decrease in oxygen concentration in a model when using different strategies of oxygenation: using a special oxygenation laryngoscope, nasal oxygen, nasal high flow oxygen, and control.

Methods

In this experimental study we compared no oxygen application as a control, standard pure oxygen application of 10 l·min^− 1 via nasal cannula, high flow 90% oxygen application at 20 l·min^− 1 using a special nasal high flow device, and pure oxygen application via our oxygenation laryngoscope at 10 l·min^− 1. We preoxygenated a simulation lung to 97% oxygen concentration and connected this to the trachea of a manikin model simulating apnoeic oxygenation. Decrease in oxygen concentration in the simulation lung was measured continuously for 20 min.

Results

Oxygen concentration in the simulation lung dropped from 97 ± 1% at baseline to 40 ± 1% in the no oxygen group, to 80 ± 1% in the standard nasal oxygen group, and to 73 ± 2% in the high flow nasal oxygenation group. However, it remained at 96 ± 0% in the oxygenation laryngoscope group (p < 0.001 between all groups).

Conclusions

In this technical simulation, oxygenation via oxygenation laryngoscope was more effective than standard oxygen insufflation via nasal cannula, which was more effective than nasal high flow insufflation of 90% oxygen.

Apneic laryngeal oxygenation during elective fiberoptic intubation - a technical simulation

Background

Sedation during elective fiberoptic intubation for difficult airway can cause respiratory depression, apnea and periods of desaturation. During apneic episodes, hypoxemia can be prevented by insufflation of oxygen in the deep laryngeal space. The aim of this study was to evaluate an oropharyngeal oxygenation device (OOD) designed for deep laryngeal insufflation during fiberoptic intubation.

Methods

The OOD is split in the front to form a path for the bronchoscope. An external lumen delivers oxygen in the deep laryngeal space. In this experimental study, air application (as control group), oxygen application via nasal prongs, oxygen application via the OOD, and oxygen application via the working channel of a bronchoscope were compared in a technical simulation. In a preoxygenated test lung of a manikin, decrease of the oxygen saturation was measured over 20 min for each method.

Results

Oxygen saturation in the test lung dropped from 97 ± 1% (baseline in all groups) to 58 ± 3% in the control-group (p < 0.001 compared to all other groups) and to 78 ± 1% in the nasal prong group (p < 0.001 compared to all other groups). Oxygen saturation remained at 95 ± 2% in both the OOD group and the bronchoscopy group (p = 0.451 between those two groups).

Conclusion

Simulating apneic laryngeal oxygenation in a preoxygenated manikin, both oxygen insufflation via the OOD and the bronchoscope kept oxygen saturation in the test lung at 95% over 20 min. Both methods significantly were more effective than oxygen insufflation via nasal prongs.

One Notable Complication of Nasopharyngeal Airway: A Case Report

Introduction

The nasopharyngeal airway (NPA) is used by emergency providers and first responders to assist with oxygenation in obtunded, critically ill patients. There are few recorded NPA complications.

Case Report

We describe a unique case in which a patient went multiple days with recurrent symptoms of upper airway obstruction secondary to retained NPA.

Discussion

Nasopharyngeal airways may be uniquely prone to being displaced and retained due to their use in emergent situations, their small size, and time of insertion in the field prior to emergency department (ED) contact where handoff is not often standardized.

Conclusion

The use of large-flanged NPAs might reduce incidences of displacement into the nasal cavity. This case highlights the need for improved handoff communication between emergency medical services and ED staff, especially to account for all inserted devices to prevent foreign body retention.

A preinstalled nasopharyngeal airway in the right nasal passageway to facilitate nasogastric intubation in anesthetized and intubated patients: a prospective randomized controlled trial

BACKGROUND

Nasogastric intubation (NGI) is usually challenging in patients under general anesthesia, with reported success rate at the first attempt to be less than 50%. The aim of this study was to investigate whether a preinstalled nasopharyngeal airway (NPA) in the right nasal passageway can facilitate NGI in anesthetized and intubated patients.

METHODS

A prospective randomized controlled trial including 108 patients scheduled for elective intra-abdominal surgeries requiring a nasogastric tube (NGT) was conducted. Fifty-three patients were randomized to receive NGI through a preinstalled NPA in the right nasal passageway (Group NPA) and 55 patients to receive NGI via the right nostril (Group O). The primary outcomes were success rates of NGI at first attempt, success rates of NGI in accumulative attempts, durations of successful NGI at the first attempt and success rates of NGI for the rescuing methods. The secondary outcomes were bleeding incidence and hemodynamic changes induced by NGI.

RESULTS

Success rate of NGI at the first attempt was 83.0% in Group NPA compared with 47.3% in Group O [P < 0.001; absolute risk reduction (ARR) = 35.7%, 95% confidence interval (CI) = 19.1-52.4%; relative risk reduction (RRR) = 67.8%] and success rate of NGI in accumulative attempts (two attempts maximum) was 88.7% in Group NPA compared with 63.6% in Group O (P = 0.002; ARR = 25.0%, 95% CI = 9.7-40.4%; RRR = 68.9%). Duration for NGI successful at the first attempt in Group NPA was significantly longer than that in Group O (56.3 vs. 27.1 s; P < 0.001; Mean difference = 29.2 s, 95% CI = 20.0-38.4 s). Neither bleeding incidence nor hemodynamic response is significantly different between the two study groups.

CONCLUSIONS

The study indicates a preinstalled NPA in the right nasal passageway facilitates NGI in anesthetized and intubated patients as an initial NGI method and as a rescuing method for patients undergoing two unsuccessful initial attempts of NGI without a preinstalled NPA. However, the NPA method proved to take more time than the routine method for NGI successful at the first attempt.

TRIAL REGISTRATION

The study was conducted after receiving approval from Institutional Review Board of Chang Gung Memorial Hospital, Linkou branch, Taiwan (registration number 201800138A3; April 11, 2018), and the clinicaltrials.gov (NCT03697642; Principal Investigator: Ting-Yang Huang; Date of registration: October 4, 2018; https://www.clinicaltrials.gov/NCT03697642 ).

Alternative Transoral Application of Nasopharyngeal Airways

Transoral application of a nasopharyngeal airway (NPA) is a novel technique for difficult airway management. Clinically, it is an effective alternative for use in nonintubated dental cases under total intravenous anesthesia. This technique can help improve oxygenation and ventilation in clinical situations in which the conventional use of NPAs is ineffective, such as in patients who have findings of obesity; mandibular retrognathia or hypoplasia; maxillary hypoplasia; macroglossia; nasal obstruction secondary to hypertrophic tonsillar, adenoid, and/or lymphoid tissues or nasal polyps; known unusual nasal anatomy (eg, septal deviation); high risk of prolonged epistaxis (eg, patients on anticoagulants); or those who demonstrate mouth-breathing behaviors during deep sedation/nonintubated general anesthesia. After ensuring proper supraglottic placement, the transorally positioned NPA can be further secured with the use of tape for the duration of the dental procedure. Unlike an oropharyngeal airway, this simple and cost-efficient technique facilitates intraoral access for dental treatment.

The management of unanticipated difficult airways in children of all age groups in anaesthetic practice - the position paper of an expert panel

Children form a specific group of patients, as there are significant differences between children and adults in both anatomy and physiology. Difficult airway may be unanticipated or anticipated. Difficulties encountered during intubation may cause hypoxia, hypoxic brain injury and, in extreme situations, may result in the patient’s death. There are few paediatric difficult-airway guidelines available in the current literature, and some of these have significant limitations. This position paper, intended for unanticipated difficult airway, was elaborated by the panel of specialists representing the Polish Society of Anaesthesiology and Intensive Care as well as the Polish Neonatal Society. It covers both elective intubation and emergency situations in children in all age groups. An integral part of the paper is an algorithm. The paper describes in detail all stages of the algorithm considering some modification in specific age groups, i.e. neonates.

Rectal Trumpet-Associated Hemorrhage in the Intensive Care Unit: A Quality Improvement Initiative

The rectal trumpet (RT) is a nasopharyngeal airway device that is inserted into the rectum for management of fecal incontinence. No published data exist on adverse events caused by the use of an RT. The purpose of this quality improvement project was to determine the rate of RT-associated hemorrhage among patients treated with an RT in our transplant intensive care unit (TICU). This quality improvement initiative and retrospective medical record review included all patients (N = 3933) cared for in a single specialty intensive care unit at a tertiary academic medical center between January 1, 2014, and May 31, 2016. We estimate that approximately 400 patients were treated with an RT. We found 3 possible and 9 probable cases of RT-associated hemorrhage, resulting in an estimated incident rate of 3% among RT-treated patients. All of these patients underwent invasive procedures for hemostasis. They received a mean of 4.9 units of packed red blood cell transfusions, and 9 experienced hypotension. Eight out of the 9 probable RT-associated hemorrhage patients experienced hemorrhage only after greater than 7 days of treatment with an RT. Following this initiative, RT use was banned in our TICU. The use of RTs can cause hemorrhage with clinically significant consequences.

Estimation of nares-to-epiglottis distance for selecting an appropriate nasopharyngeal airway

The nasopharyngeal airway is an important equipment in airway management, a correct placement is crucial for its effectiveness. We measured the nares-to-epiglottis distance (NED) and examined the correlations of the optimal insertion length (NED-1) with patient characteristics and various external facial measurements. We aimed to develop a simple method for estimating the optimal insertion length and to help select an appropriate nasopharyngeal airway.Two hundred patients of ASA grade I & II aged >20 years undergoing elective surgery under general anesthesia were enrolled. We measured nares-to-ear tragus distance (NTD), nares-to-mandibular angle distance (NMD), philtrum-to-ear tragus distance (PTD), and philtrum-to-mandibular angle distance (PMD). The NED was measured by fiber-optic bronchoscope. All measurements were obtained in centimeters. NED-1 (cm) was defined as the optimal insertion length. The patient's sex, age, body weight, body height, and body mass index were recorded.The NED-1 significantly correlated with body weight, body height, NTD, NMD, PTD, and PMD. Backward stepwise multiple linear regression analysis yielded the formula for predicting NED-1: 0.331 - 0.018 × BW + 0.061 × BH + 1.080 × NMD - 1.256 × PMD + 0.697 × PTD (r = 0.640, P < .001). The regression lines of the optimal insertion length versus PTD showed the best fit to the equality line. The measurements of PTD showed the minimal differences from NED-1 and with the most patients showing <1 cm differences from NED-1.The optimal insertion depth of nasopharyngeal airway can easily be predicted by the distance from philtrum-to-ear tragus, and a nasopharyngeal airway of an appropriate size can be selected accordingly.

Nasopharyngeal airway aspiration: An uncommon cause of sudden respiratory distress in hospitalized patients

An elderly, bed ridden patient with a history of stroke was admitted for management of aspiration pneumonia. Two days after insertion of a nasopharyngeal airway, sudden respiratory distress prompted further investigations which led to the eventual diagnosis and removal of the nasopharyngeal airway that had been aspirated. The device was removed under conscious sedation with fiber optic bronchoscopy.

Airway management – a review of current methods, guidelines and equipment

Maintaining airway patency is an essential issue in many fields of medicine. The modern approach to CPR, which focuses on maintaining airway, breathing, and circulation was finally established by Peter Safar in his book ABC of Resuscitation (1950). At present, along with the development of evidence-based medicine, techniques which are proven to be clinically effective are regularly published in a convenient form – as bundles and guidelines. Regarding airway management, ERC and DAS guidelines are the most reliable and useful sources of knowledge and practical clinical advice. Among the medical staff, there is emphasis put on the mastery of AB C techniques. Airway management is the first step in the resuscitation algorithm. It consists of a variety of procedures ranging from simple and non-invasive to more complex, requiring professional training and experience. Currently, the most clinically effective and life-saving actions are incorporated into whole procedures and bundles, such as ERC or DAS guidelines, which are evenly checked, evaluated and, eventually, modified. This method of regular revision allows us to keep all medical professionals at the same level of competence. The aim of the study was to describe basic and advanced techniques, methods, and devices which are currently used to provide it. Currently applicable guidelines regarding CPR and airway management were reviewed and summarized.

Interventional Drug-Induced Sleep Endoscopy: A Novel Technique to Guide Surgical Planning for Obstructive Sleep Apnea

STUDY OBJECTIVE

One of the challenges of surgery for obstructive sleep apnea (OSA) is identifying the correct surgical site for each patient. The objective of this study was to use drug-induced sleep endoscopy (DISE) and nasopharyngeal tube (NPT) placement to determine the effect of eliminating palatal collapse on the obstruction seen on other segments of the upper airway.

METHODS

Forty-one OSA patients were enrolled in this prospective study. All patients had a polysomnogram followed by DISE. DISE findings were recorded and compared with and without placement of a NPT. Obstruction was graded with a scale that incorporates location, severity, and interval of obstruction.

RESULTS

Most patients (83%) demonstrated multilevel obstruction on initial DISE. With the nasopharyngeal airway in place, many patients with multilevel obstruction had at least a partial improvement (74%) and some a complete resolution (35%) of collapse (p < 0.05). Reduction in collapse was observed at the lateral walls (86%), epiglottis (55%), and tongue base (50%). NPT placement did not significantly alter upper airway morphology of patients with incomplete palatal obstruction or mild OSA.

CONCLUSIONS

To our knowledge, this is the first study to evaluate the effect of soft palatal stenting on downstream pharyngeal obstruction during DISE. Our study provides evidence that reducing soft palatal collapse can reduce negative pharyngeal pressure and thereby alleviate other sites of upper airway obstruction. Taken together, these findings provide a means to identify appropriate candidates for isolated palatal surgery and better direct a minimally invasive approach to the surgical management of OSA.

Scandinavian SSAI clinical practice guideline on pre-hospital airway management

Background

The Scandinavian society of anaesthesiology and intensive care medicine task force on pre‐hospital airway management was asked to formulate recommendations following standards for trustworthy clinical practice guidelines.

Methods

The literature was systematically reviewed and the grading of recommendations assessment, development and evaluation (GRADE) system was applied to move from evidence to recommendations.

Results

We recommend that all emergency medical service (EMS) providers consider to: apply basic airway manoeuvres and airway adjuncts (good practice recommendation); turn unconscious non‐trauma patients into the recovery position when advanced airway management is unavailable (good practice recommendation); turn unconscious trauma patients to the lateral trauma position while maintaining spinal alignment when advanced airway management is unavailable [strong recommendation, low quality of evidence (QoE)]. We suggest that intermediately trained providers use a supraglottic airway device (SAD) or basic airway manoeuvres on patients in cardiac arrest (weak recommendation, low QoE). We recommend that advanced trained providers consider using an SAD in selected indications or as a rescue device after failed endotracheal intubation (ETI) (good practice recommendation). We recommend that ETI should only be performed by advanced trained providers (strong recommendation, low QoE). We suggest that videolaryngoscopy is considered for ETI when direct laryngoscopy fails or is expected to be difficult (weak recommendation, low QoE). We suggest that advanced trained providers apply cricothyroidotomy in ‘cannot intubate, cannot ventilate’ situations (weak recommendation, low QoE).

Conclusion

This guideline for pre‐hospital airway management includes a combination of techniques applied in a stepwise fashion appropriate to patient clinical status and provider training.

A dual-use laryngoscope to facilitate apneic oxygenation

BACKGROUND

In preoxygenated patients, time until oxygen saturation drops can be extended by insufflating oxygen into their airways, thus oxygenating them apneically.

OBJECTIVES

To compare different methods of apneic oxygenation.

METHODS

A noncommercial dual-use laryngoscope with an internal lumen in its blade was used to provide oxygen insufflation into a simulated laryngeal space during intubation. In this experimental study, oxygen insufflation via the dual-use laryngoscope was compared with no oxygen insufflation, with nasal oxygen insufflation, and with direct intratracheal oxygen insufflation. In a preoxygenated test lung of a manikin, oxygen percentage decrease was measured over a 20-min observation period for each method of oxygen application.

RESULTS

Oxygen percentage in the test lung dropped from 97% to 37 ± 1% in the control group (p < 0.001 compared to all other groups) and to 68 ± 1% in the nasal insufflation group (p < 0.001 compared to all other groups). Oxygen percentage remained over 90% in both the direct intratracheal insufflation group (96 ± 0%) and the laryngoscope blade insufflation group (94 ± 1%) (p < 0.01 between the latter two groups).

CONCLUSIONS

Simulating apneic oxygenation in a preoxygenated manikin, deep laryngeal oxygen insufflation via the dual-use laryngoscope kept oxygen percentage in the test lung above 90%, and was more effective than oxygen insufflation via nasal prongs.

Helping anesthesiologists understand facial fractures

Injuries to the oral and maxillofacial region are commonly encountered, and the appropriate management of patients with these injuries frequently requires the expertise of an anesthesiologist. Injuries to this region may involve any combination of soft tissue, bone, and teeth. Injuries to these structures often produce anesthesia-related challenges, which must be overcome to achieve optimal outcomes. This article addresses the common challenges faced by anesthesiologists specific to patients with facial fractures.

Emergency medicine techniques and the forensic autopsy

Emergency medicine measures often have to be carried out under suboptimal conditions in emergency situations and require invasive patient treatment. In the case of a fatal outcome these measures have to be evaluated at autopsy, regarding indications, correct implementation and possible complications. As well, alongside the more familiar procedures--such as endotracheal intubation, insertion of chest drains, external cardiac massage and cannulation of central and peripheral veins--there are alternative techniques being increasingly applied, that include new tools for the management of hemorrhagic shock, drug delivery and alternative airway management devices. On the one hand, all of these measures are essential for the survival and appropriate treatment of the injured and/or sick patient, but on the other hand they can damage the patient and thus contain a significant risk of both medical and forensic relevance for the patient and the physician. In the following review we provide an overview of established, new and alternative techniques for emergency airway management, administration of drugs and management of hemorrhagic shock. The aim is to facilitate the understanding and autopsy evaluation of current emergency medicine techniques.

Airway obstruction after biopsy by cervical mediastinoscopy in a patient with a mediastinal mass -A case report-

Biopsy, using mediastinoscopy is commonly employed for accurate histologic diagnosis of a mediastinal mass. However, since the mass is not removed during the procedure, it may cause compression of vital structures such as major airways, the heart, the pulmonary artery, and the superior vena cava after surgery. We observed a case of a 66-year-old man with a mediastinal mass that caused severe airway obstruction during recovery from anesthesia following mediastinoscopic biopsy, probably caused by upper airway edema which seemed to originate from compression of the superior vena cava. Therefore, we suggest that unexpected airway obstruction in a patient with a mediastinal mass can be due to superior vena cava compression.

Securing a nasopharyngeal airway

OBJECTIVE

The nasopharyngeal airway is a simple airway adjunct used by various healthcare professionals. It is the least invasive method of safely managing upper airway obstruction. The objective of this report was to describe a rapid and very simple method of securing a nasopharyngeal airway in an agitated patient.

METHOD

We describe a simple method of securing a nasopharyngeal airway, using safety pins and tapes.

RESULT

This technique has been used by the authors in several emergency situations and has been found to be quick and effective.

CONCLUSION

The nasopharyngeal airway is a simple piece of equipment that is cheap and easy to use. The technique described in this article is a simple, practical and effective method of securing a nasopharyngeal airway in an emergency situation.