Oropharyngeal Airway Research Articles

Evolving role of video laryngoscopy for airway management in the emergency department

Evolving role of video laryngoscopy for airway management in the emergency department

Bilateral Choanal Atresia: Is it Really a Surgical Emergency?

To review the need of emergency recanalization surgical procedure in cases of bilateral choanal atresia. A retrospective analysis was undertaken for the cases of bilateral choanal atresia which were recanalized between January 2000 and February 2010 in a teaching hospital. Out of 135,954 live births (0.004%), six cases of bilateral choanal atresia were diagnosed and operated during this period. Five cases were hospital deliveries from our hospital whereas one case was referred from another hospital. Three cases were recanalized with dilatation procedure whereas the other three were endoscopically recanalized with micro-drill. All the cases were operated in routine operation theatre. All were managed with orogastric tube or oropharyngeal airway during the waiting period for surgery. No neonate required emergency intubation or tracheostomy. The average age at the time of surgery was 10days (range 5-21days). As per our observations recanalization surgery for bilateral choanal atresia is not a surgical emergency. Neonates can be managed temporarily with orogastric tube/oropharyngeal airway during waiting period. Subsequently surgery can be done in routine and unhurried operation theater by experienced surgical hands thus minimizing the morbidity.

Arco-palato-uvular flap: a new surgical technique for the treatment of palatal snoring in tonsillectomized patients

We describe a new surgical technique called "arco-palato-uvular flap (APUF)" which can be used for the surgical management of palatal snoring in previously tonsillectomized patients. Among patients who were admitted to the Military Hospital of Novi Sad between January 2000 and December 2004, 36 patients (19 males, 17 females; mean age 45.3 years; range 21 to 60 years) who had previously undergone tonsillectomy for various reasons and who were thought to have palatal snoring based on physical and endoscopic examinations were evaluated on the basis of the visual analog scale (VAS), Epworth sleepiness scale (EPSS) and apnea hypopnea index (AHI) scores and underwent APUF surgery after giving informed consent. Twenty-seven patients with a body mass index (BMI) of <30 kg/m2 had socially-bothersome snoring and nine had mild sleep apnea (AHI 5-15/hour, SO2 >90%). The mean visual analog scale scores were 8.6 ± 1.0 preoperatively and 2.3 ± 1.5 postoperatively. The Epworth Sleepiness Scale scores averaged 10.0 ± 3.0 preoperatively and 4.0 ± 1.0 postoperatively. In patients with mild apnea, the average preoperative AHI was 11.58 ± 3.58 and dropped to 4.75 ± 2.92 postoperatively. Statistical analysis revealed significant reductions in all variables (p<0.001). The APUF procedure may treat palatal snoring and mild obstructive sleep apnea in previously tonsillectomized patients by widening the oropharyngeal airway, and stabilizing the uvulopalatal segment. Further studies are needed to determine the long-term success rates of the technique and to modify the patient selection and exclusion criteria.

Assessment of oropharyngeal airway dimensions in skeletal class II cases treated with twin block appliance

Assessment of oropharyngeal airway dimensions in skeletal class II cases treated with twin block appliance

Use of two tracheal tubes and fibreoptic bronchoscope for intubation through a LMA Pro‐Seal® in a difficult paediatric airway

In a case of predicted difficult intubation in a 5-year-old child, we induced anaesthesia with sevoflurane in oxygen. We were able to establish adequate mask ventilation with help of a size 2 oropharyngeal airway (Intersurgical Ltd., Berkshire, UK). After deepening the plane of anaesthesia, we inserted a size 2 laryngeal mask airway (LMA Pro-Seal®; LMA North America, Inc. San Diego, CA, USA). We then introduced a 2.2-mm flexible fibreoptic bronchoscope (Karl Storz GMBH & Co, Tuttlin, Germany) through the LMA to evaluate its position and the tracheal lumen, and to negotiate the tracheal tube under direct vision. A 4-mm external diameter tracheal tube is the maximum recommended size that can be inserted through a size 2 LMA Pro-Seal. However, the length of this tube is such that it just crosses the bowl of the LMA Pro-Seal. We therefore attached a 3.5-mm external diameter uncuffed tracheal tube to the connector end of a 4-mm tube (Flexicare medical Ltd., Mid Glamorgan, UK) as a tube stabiliser and extension. Following introduction of the assembly through the LMA, we were able to advance both tubes off the fibrescope and site the 4-mm tracheal tube just above the carina. We removed the bronchoscope and then the LMA over the two tubes. We disconnected the 3.5-mm tube and attached a standard connector to the 4-mm tracheal tube. We were able to maintain spontaneous ventilation until the trachea was successfully intubated, and we would recommend this technique to aid intubation in the difficult paediatric airway.

A Modified Difficult Airway Management Algorithm Incorporating Video Devices in Routine Anesthesia Practice

A Modified Difficult Airway Management Algorithm Incorporating Video Devices in Routine Anesthesia Practice

The laryngeal mask airway and otorhinolaryngology head and neck surgery

To review the use of the laryngeal mask airway (LMA) in otorhinolaryngology, as well as the advantages and disadvantages across the range of procedures typically performed. Contemporary review. Published articles identified through PubMed, Medline, and conference proceedings were reviewed. With only minimal stimulation of the oropharyngeal airway at the time of insertion and removal, the LMA provides safe, hands-free airway maintenance and is ideally suited to many of the procedures performed in otorhinolaryngology. The relationship between surgeon and anesthetist is particularly strong in otorhinolaryngology. The impact of airway management on the surgical field and perioperative conditions requires the surgeon to be aware of contemporary tools and techniques available. The LMA has been shown to be safe and efficacious by both the literature and clinical practice. Its use in selected patients should be encouraged.

Modified internal mandibular distraction osteogenesis in the treatment of micrognathia secondary to temporomandibular joint ankylosis: 4-Year follow-up of a case

Micrognathia and obstructive sleep apnoea syndrome (OSAS) are problems subsequent to temporomandibular joint ankylosis (TMJa) in growing patients. For patients with micrognathia and OSAS secondary to TMJa, it is important to restore proper mandibular form and dimension, achieve occlusal stability and recover satisfactory joint movement.We report a 4-year follow-up of a patient with micrognathia and OSAS secondary to bilateral TMJa. The treatment of this patient involved (1) a modified internal mandibular distraction osteogenesis without altering the pre-existing occlusion; (2) TMJ arthroplasty in which the dislocated disc was found and repositioned and the shape of the glenoid fossa and articular head was formed without removing bone in vertical dimension; (3) passive mouth-opening exercise with an individualized occlusal pad postoperatively for one month; and (4) orthodontic treatment for the occlusal disturbance and active mouth-opening exercise for one year. After the treatment the micrognathia was corrected; the oropharyngeal airway was increased significantly; mouth-opening increased to 40mm intraoperatively was maintained at 36.66mm 4 years after surgery. Satisfactory occlusion was achieved after orthodontic treatment. Through the 4-year follow-up, no signs of reankylosis were found. In conclusion, this new clinical protocol is a safe, effective and quick way to treat micrognathia and OSAS secondary to TMJa.

Influence of myofunctional therapy on oropharyngeal airway dimensions in skeletal class II cases - a cephalometric study

Skeletal Class II malocclusion is associated with a multitude of functional problems one of which is reduced oropharyngeal airway dimension. The airway is receiving renewed attention in recent literature regarding snoring and obstructive sleep apnoea syndrome especially as a retrognathic mandible is often implicated as its cause. The study was undertaken to investigate the myofunctional appliance (TWIN BLOCK) effects on the oropharyngeal airway dimensions in Skeletal Class II individuals in the average age of 11-13 years. This study also expresses the existence of any correlation between airway dimension and craniofacial morphology.

Approach to a Child with Breathing Difficulty

Breathing difficulty and respiratory distress is the most common cause of admission to the Pediatric Emergency. Respiratory distress presents as altered breathing pattern, forced breathing efforts or obstructed breathing, and chest indrawing; respiratory failure is defined as paCO(2) >50 mmHg (inadequate ventilation) and/or a paO(2) < 60 mmHg (inadequate oxygenation). Rapid assessment is aimed to ascertain adequacy of airway patency, breathing, and circulation. Immediate care is directed at (a) restoration of airway patency- by positioning (head tilt -chin lift), cleaning the oropharynx, and/or insertion of oropharyngeal airway; (b) supporting breathing- with high flow oxygen and assisted ventilation (with bag and mask or endotracheal intubation and ventilation), and (c) restoration of circulation- using fluid boluses and inotropes, if necessary. Immediate specific management may require endotracheal intubation/tracheostomy for upper airway obstruction; needle thoracotomy and drainage of pneumothorax; and first dose of antibiotic for febrile children. Thereafter meticulous history, focused physical examination, and specific laboratory/radiological investigations are undertaken to identify the underlying cause. At the end of this, one should be able to categorize the child to one of the following: (a) upper airway obstruction, (b) pneumonia (syndrome of cough, fever and breathing difficulty), (c) lower airway obstruction, (d) slow or irregular breathing without pulmonary signs, and (e) respiratory distress with cardiac findings, to initiate specific treatment. Further respiratory support by Continuous Positive Airways Pressure (CPAP) and mechanical ventilation may be required in some cases. All children with respiratory distress must be monitored for early detection of worsening/complications, assessment of response to therapy and rapid documentation of clinical state.

Determination of the proper size of oropharyngeal airway: Correlation with external body measurements

Determination of the proper size of oropharyngeal airway: Correlation with external body measurements

Airway volume for different dentofacial skeletal patterns

Our objective was to evaluate the nasal passage (NP) and oropharyngeal (OP) volumes of patients with different dentofacial skeletal patterns. The study sample consisted of 140 patients (70 boys, 70 girls), divided into 3 groups as Class I (1 ≤ ANB ≤ 3), Class II (ANB > 3), and Class III (ANB < 1), and then further divided into 4 groups as SNA angle ≥ 80°, SNA angle <80°, SNB angle ≥78°, and SNB angle < 78° to evaluate how the positional changes in the maxilla and the mandible affect the OP and NP variables. Differences between groups were determined by using the Kruskal-Wallis test. Correlations between the variables were tested with the Spearman correlation coefficient. The linear multiple regression test was applied to create a model for the airway volumes separately. The OP volume of the Class II subjects (n = 50) was significantly lower when compared with that of the Class I (n = 46) and Class III subjects (n = 44). The only statistically significant difference for NP volume was observed between the Class I and Class II groups. The mean OP airway volume of subjects with retruded mandibular positions was statistically significantly smaller when compared with the subjects with higher SNB angles. The area of the most constricted region at the base of the tongue (minAx) had a high potential in explaining the OP volume, whereas the NP volume models were not as successful as the OP counterpart. However, minAx was also entered into the NP volume equations as an explanatory variable. The OP airway volumes of Class II patients were smaller when compared with Class I and Class III patients. It was observed that mandibular position with respect to cranial base had an effect on the OP airway volume. The only significant difference for the NP volume was between the Class I and Class II groups, with a smaller volume observed for the Class II group.

Impact of the O-C2 Angle on the Oropharyngeal Space in Normal Patients

Radiographic analysis using normal patients. To analyze the relationship between the cervical alignment and the oropharyngeal space. Few clinical studies stress the effect of the occipito-C2 (O-C2) alignment on the oropharyngeal space. A previous study showed dysphagia and/or dyspnea after occipitocervical fusion was caused by oropharyngeal stenosis resulting from O-C2 fixation in a flexed position. Other independent researchers showed that development or improvement of obstructive sleep apnea in rheumatoid arthritis patients was related to the O-C2 alignment. However, there are limited basic data demonstrating the relationship between the O-C2 alignment and the oropharyngeal space. Plain lateral cervical radiographs in five tested positions--neutral, flexion, extension, protrusion, and retraction--of 40 asymptomatic volunteers were collected. The O-C2 angle, the C2-C6 angle, and the anterior-posterior distance of the narrowest oropharyngeal airway space (nPAS) were measured, and the changes in value from the neutral to the other four positions were calculated for each patient. According to the multiple regression analysis, there was an extremely strong linear correlation of the change in the O-C2 angle with the percentage change in the nPAS. Referring to the multiple regression analysis, a decrease of 10° in the O-C2 angle caused a 37% reduction in the nPAS in the neutral position. In contrast, no significant correlation was found between the change in the C2-C6 angle and the percentage change in the nPAS. Our results show the impact of the O-C2 angle on the oropharyngeal space. This knowledge will be useful for the diagnosis and treatment of the upper cervical lesion combined with the upper airway stenosis, and for the determination of the optimal fixation angle in occipitocervical fusion.

Three-dimensional analysis of pharyngeal airway form in children with anteroposterior facial patterns

To test the null hypothesis that the form and size of the pharyngeal airways in preadolescents do not differ among various skeletal patterns. Sixty healthy children (mean age, 11.79 ± 1.11 years) were divided into three groups by anteroposterior jaw relationships. Using cone-beam computed tomography, the inclination and the volume of the pharyngeal airway were measured and compared with craniocervical angles and cephalometric variables. Children with Class II malocclusion have a larger angle between the FH plane and midplane of the oropharyngeal airway (ang-OA) compared with children with Class I and III malocclusion (P < .01). Ang-OA was significantly correlated with craniocervical angle (ang-cc) and anteroposterior variables, mainly ANB angle, Pog-N perpendicular (P < .01). Airway volume had a positive correlation with facial depth (P < .01). Children with Class II malocclusion have more backward orientation and smaller volume of the pharyngeal airway than do children with Class I and III malocclusion. Inclination of the oropharyngeal airway might be a key factor in determining the form of the entire pharyngeal airway and is related to head posture.

Sagittal airway changes: rapid palatal expansion versus Le Fort I osteotomy during maxillary protraction

The purpose of the present study was to evaluate upper airway changes related to craniofacial changes induced by a facemask (FM) combined with Le Fort I osteotomy without down-fracture in Class III maxillary retrusion subjects (group 1) when compared with a similar group of subjects treated with traditional rapid palatal expansion and FM therapy. Pre- (T1) and post- (T2) protraction cephalometric radiographs of group 1 (10 females and 6 males; mean age 12.75 ± 1.91 years) and group 2 (7 females and 9 males; mean age 12 ± 1.7 years) were traced. The treatment duration was 149 ± 14 days (approximately 5 months) and 270 ± 46 days (approximately 9 months) for groups 1 and 2, respectively. A paired t-test for intergroup comparisons of values at T1, an independent samples t-test for intragroup comparisons of values at T1 and T2, and a non-parametric Mann-Whitney U-test for intergroup comparisons were used. To evaluate the relationship between changes in upper airway dimension and craniofacial morphology, a multiple-regression analysis was performed. Significant maxillary protraction along with clockwise rotation of the mandible was achieved in both groups. Counter-clockwise maxillary rotation was significant in group 1 (P < 0.05) but not in group 2. While nasopharyngeal measurements (PNS-ad1, PNS-ad2) showed significant increases (P < 0.05) as a result of treatment in both groups, oropharyngeal measurements did not change. Maxillary protraction, which was achieved in both groups but in a shorter period of time in group 2, improved nasopharyngeal but not oropharyngeal airway dimensions.

Educating the Educator: Teaching Airway Adjunct Techniques in Athletic Training

T he 5th edition of the Athletic Training Education Competencies (Competencies) now requires athletic training educators (ATEs) to introduce into the curriculum various types of airway adjuncts including: (1) oropharyngeal airways (OPA), (2) nasopharyngeal airways (NPA), (3) supraglottic airways (SGA), and (4) suction. The addition of these Acute Care (AC) knowledge and skill competencies, as well as others (eg, rectal temperature, oxygen saturation, blood glucose level, nebulizers) were incorporated into the curriculum to reflect the National Athletic Trainers’ Association’s published position statement recommendations or those in development.1 The specific knowledge and skill statements addressing these educational areas can be found in Table 1. However, for many ATEs teaching airway adjuncts and suctioning is an unfamiliar concept. Therefore, the purpose of this column is to provide the ATE with a resource document on how to use and teach different adjunct breathing devices within their educational program.

Changes in oropharyngeal airway and respiratory function during sleep after orthognathic surgery in patients with mandibular prognathism

The aim of this study was to examine the effects of mandibular setback surgery on pharyngeal airway space and respiratory function during sleep. The subjects were 22 patients in whom mandibular prognathism was corrected by bilateral sagittal split ramus osteotomy; either one jaw or two jaw surgery. Polysomnography was performed before surgery and 6 months after surgery, and the apnea hypopnea index (AHI) and arterial oxygen saturation during sleep were measured to assess respiratory function during sleep. Morphological changes were studied using cephalograms taken immediately before, a few days after and 6 months after surgery. As a control, 10 subjects without sleep-disordered breathing underwent the same examinations. AHI was not changed significantly after surgery, although two patients were diagnosed with mild obstructive sleep apnea (OSA) syndrome after surgery. They were not obese, but the amounts of mandibular setback at surgery were large. In conclusion, a large amount of mandibular setback might inhibit biological adaption and cause sleep-disordered breathing, and it might be better to consider maxillary advance or another technique that does not reduce the airway for patients with skeletal class III malocclusions who have large anteroposterior discrepancy and/or maxillary hypoplasia.

Oropharyngeal airway dimensions after treatment with functional appliances in class II retrognathic children

Class II skeletal malocclusion and respiratory disorders owing to the obstruction of the upper airway at early growth stages have been correlated. The retro/micrognathism can be treated with functional appliances. However, the effects of an early functional orthopedic treatment on the airway dimensions have not been evaluated before the growth peak. Therefore, the objective of this study was to evaluate the changes in the airway dimensions of class II retrognathic children who received treatment with either Klammt or Bionator on a pre-pubertal stage. The sample consisted of 50 lateral cephalograms of class II retrognathic patients in a pre-puberal stage, before and after the use of a Klammt or Bionator II treatment for 1 year. The data were evaluated by Student's t-test or Mann-Whitney test, and significance was set at 5% (P < 0·05). When the measurements before and after treatment were compared, a statistically significant increase in the airway dimensions was found at the space where the adenoid tissue was located. The only airway dimensions that increased after treatment with functional appliances were the ones located at the nasopharynx. The adenoid tissue is still in the peak of growing at the ages of the subjects included in this study. However, the measurements along the nasopharynx increased when compared with the initial ones. Still, similar retrospective and prospective studies are needed at older stages.

Micro-particle deposition and lobar distribution of mass flow in human upper respiratory tract model

A representative human upper respiratory tract model consisting of oropharyngeal and asymmetric tracheobronchial (TB) airways from the trachea (G0) to the main lobar bronchi (G2) was constructed. Laminar-to-turbulent airflow for typical inhalation modes as well as micro-particle transportation, wall deposition and mass flow to lobes was simulated using the CFX10.0 software from Ansys Inc. The numerical particle deposition efficiency of the oropharynx region and two generations (G1 and G2) of TB airways shows great agreement with the experimental data obtained from realistic casts. The particle deposition pattern indicates that inertial impaction is the primary mechanism in the human upper airway, and turbulence dispersion performs crescent influence especially for small particles. The initial positions of particles with different fates are confined to specifically concentrated zones. The particle mass distributions of five lobes are close to airflow distributions. The upper lobes receive fewer particles than lower lobes and the right middle lobe receives the least.

Respiratory distress in Pierre Robin sequence: an experience with mandible traction by wires

Congenital retrognathia and glossoptosis characterize isolated Pierre Robin sequence (iPRS); the small mandible and its retracted position cause retrodisplacement of the tongue and reduction of the oropharyngeal airway. These neonates may be affected by airway obstruction, feeding difficulties, failure to thrive, and chronic hypoxaemia. To solve the respiratory problems secondary to glossoptosis, various treatments have been described including prone positioning, a nasopharyngeal tube, glossopexy, and mandibular distraction. Over the last 28 years, the authors have treated 118 neonates and infants affected by iPRS by carrying out traction of the mandible using two parasymphyseal wires, positioned under local anaesthesia. All the procedures were successful, with no major complication. The patients' respiratory problems and apnoea disappeared suddenly after beginning traction.