The use of the cuffed oropharyngeal airway in paediatric patients

BACKGROUND: The cuffed oropharyngeal airway (COPA) is a device which has already been demonstrated to be suitable for anaesthetized adult patients undergoing either spontaneous or mechanical ventilation. There are few reports on the use of the COPA in children. In this study, the authors assessed the COPA in paediatric patients undergoing minor surgery. METHODS: The same anaesthesiologist inserted the COPA in 40 consecutive paediatric patients, ASA I and II, aged 1.8-15.3 years. (7.4 +/- 3.9), after induction of anaesthesia with N2O/O2/sevoflurane. COPA size was chosen by measuring the distal tip of the device at the angle of the jaw with the COPA perpendicular to the patient's bed. The proper positioning of the COPA was assessed by observing thoracoabdominal movements, regular capnograph trace, the reservoir bag movements and SpO2 > 94% with a fraction of inspired oxygen of 0.5. Anaesthesia was maintained with 1 MAC halothane, sevoflurane, or isoflurane in N2O/O2 (50%) and the patients were spontaneously breathing. The stability of the COPA following changes in head, neck and body position was tested. We recorded the duration time for COPA insertion, the side-effects of placement of the COPA and during the intraoperative period, the number of attempts, the type of manipulation in order to provide an effective airway and postoperative symptoms, such as the presence of blood on the device, sore throat, neckache, jaw pain and PONV. RESULTS: Successful COPA insertion at the first attempt was 90% and at the second attempt in the remaining 10%. The most frequent airway manipulations were head tilt in 27.5% (obtained by a pillow under shoulders) and chin lift in 5%. No complications both at COPA placement nor during the intraoperative period were observed. On the basis of weight and age, the COPA size was no. 8 in 50%, no. 9 in 30%, no. 10 in 12.5%, and no. 11 in 7.5%. The COPA demonstrated stability after changes in head, neck and body position. Postoperative complications were the presence of blood stains in one case and PONV in six cases (15%). CONCLUSIONS: The COPA is an extratracheal airway device suitable in paediatric patients undergoing general anaesthesia with spontaneous ventilation for minor surgery and other painful procedures. This study shows that for paediatric patients: (i) complications seem to be rare; (ii) the COPA allows hands free anaesthesia; (iii) specific indication for the COPA could be obese patients with a small mouth; and (iv) COPA sizing can be easily established by the weight or age of the patients.     

The cuffed oropharyngeal airway as an aid to fibreoptic intubation

The cuffed oropharyngeal airway is a new disposable airway based on the Guedel oral airway. It has an asymmetrical cuff which provides a seal as well as lifting the base of the tongue forwards, and a 15-mm connector allowing attachment to an anaesthetic breathing system. The device does not extend beyond the vallecula, so that the laryngeal inlet can be visualised with a fibreoptic laryngoscope passed between the cuff of the device and the pharyngeal wall. The advantage is that ventilation is maintained throughout the intubating sequence. We describe its use in a patient with oropharyngeal carcinoma.     

Mucosal pressures from the cuffed oropharyngeal airway vs the laryngeal mask airway

We tested the hypothesis that pressures exerted on the pharyngeal mucosa by the laryngeal mask airway (LMA) and cuffed oropharyngeal airway (COPA) differ, in 20 male and 20 female adult patients. Microchip pressure sensors were attached to the LMA and COPA at four similar anatomical locations (base of the tongue, lateral pharynx, posterior pharynx and distal oropharynx) and two dissimilar locations (LMA, piriform fossa and hypopharynx; COPA, middle of the tongue and proximal oropharynx). Cuff volume was adjusted until oropharyngeal leak pressure (OLP) was 10 cm H2O and mucosal pressures were recorded. This was repeated at an OLP of 15 cm H2O and at maximal OLP. Overall mucosal pressures were higher for the COPA than the LMA at 10 cm H2O (17 vs 3 cm H2O; P < 0.0001), at 15 cm H2O (21 vs 6 cm H2O; P < 0.0001) and at maximal OLP (26 vs 9 cm H2O; P < 0.0001). Mucosal pressures were always higher for the COPA at the base of the tongue, posterior pharynx and lateral pharynx, but were similar in the distal oropharynx. Maximal OLP was higher for the LMA than the COPA (27 (95% confidence intervals 25- 29) vs 16 (12-19) cm H2O; P < 0.0001). We conclude that pressures acting on the mucosa were higher with the COPA compared with the LMA.      

The pressor response after laryngeal mask or cuffed oropharyngeal airway insertion

BACKGROUND: Since the cuffed oropharyngeal airway (COPA) has been suggested to cause less pharyngeal trauma than the laryngeal mask airway (LMA), we conducted a prospective, randomised study to compare haemodynamic changes after placing either the COPA or LMA in healthy anaesthetised adults. METHODS: After standard midazolam premedication (0.05 mg kg(-1) IV), general anaesthesia (IV propofol 2 mg kg(-1)) was induced in 60 ASA physical status I-II, 18-65-yr-old patients, who were randomly allocated to receive COPA (n=30) or LMA (n= 30) placement and then mechanically ventilated using a 60% nitrous oxide and 1% isoflurane in oxygen mixture (TV=8 ml kg(-1), RR=12 b.p.m., I/E=1/2). Haemodynamic variables were recorded 20 min after the midazolam premedication (baseline), and then every 1 min until 10 min after general anaesthesia induction. RESULTS: Nine patients of group COPA (30%) required chin lift, jaw thrust or head tilt to maintain adequate ventilation, while no problems were observed in the LMA group (P<0.0005); however, in no case did the designed extratracheal airway have to be removed due to unsuccessful mechanical ventilation, and no signs of gastric insufflation or regurgitation were reported. The maximum mean changes in haemodynamic variables were more marked after LMA placement (SAP: 12%+/-13%; DAP: 11%+/-18%; HR: 13%+/-16%) than COPA placement (SAP: -3%+/-18%; DAP: -5%+/-16%; HR: 4%+/-13%) (P<0.005, P<0.005, and P<0.01 for SAP, DAP and HR, respectively). Group LMA showed higher SAP and DAP values than group COPA only during the first 3 min after airway insertion. CONCLUSION: In healthy, anaesthetised patients, placing a cuffed oropharyngeal airway is associated with smaller cardiovascular changes after airway insertion compared with the laryngeal mask airway.     

Fibreoptic intubation using the cuffed oropharyngeal airway and Aintree intubation catheter

A cuffed oropharyngeal airway has recently been introduced which has larger internal dimensions than a comparable Guedel airway. This allows a ventilation/exchange bougie, the Aintree Intubation Catheter, mounted on a fibreoptic laryngoscope to pass through it. Its 15-mm connector and pharyngeal cuff suggested the possibility of using a Rüsch sealed-port angle piece to allow ventilation through the oropharyngeal airway during fibreoptic laryngoscopy. This study investigated using this equipment to intubate the trachea through the cuffed oropharyngeal airway in paralysed patients, whilst maintaining ventilation manually with a Bain system. In 20 patients, airway control was satisfactory throughout and tracheal intubation was accomplished without complications. The cuffed oropharyngeal airway was easy to manipulate to improve a suboptimal fibreoptic view of the larynx. This may give it an advantage over the laryngeal mask airway when used as a ventilation/intubation conduit.     

Utilisation clinique du COPA (cuffed oropharyngeal airway)

ObjectivesTo assess the performance of the COPA device during general anaesthesia.Study designProspective, clinical, open study.PatientsEighty patients scheduled for short elective surgical procedures under general anaesthesia not requiring tracheal intubation.MethodAfter premedication (midazolam, atropine), anaesthesia was induced with propofol (154 ± 40 mg = 2.47 ± 0.8 mg·kg⁻¹) and alfentanil (1.14 ± 0.43 mg). The COPA device was inserted in a fashion similar to a Guedel airway device. The device was evaluated on the following criteria: correct choice of COPA size, ease of insertion, ability to obtain or maintain patent airway. Adverse reactions were noted, such as coughing, nausea, regurgitation, inhalation, and sore throat. The overall rating of the COPA as a “hand free device” was evaluated on the basis of excellent, good, fair, and poor.ResultsInsertion of the device was easy and in 70 cases successful on the first attempt. Jaw thrust or head tilt was necessary in half the cases. No patient necessitated intubation because of hypoxaemia or airway obstruction. Adverse reactions occurred in few cases and consisted of sore throat (always moderate) in 10% of the cases. COPA was evaluated as excellent or good in 80% of the cases.ConclusionCOPA is a convenient device for airway management in fasting patients undergoing general anaesthesia for elective surgery in the supine position, in whom tracheal intubation is not indicated.     

New developments in the management of the paediatric airway: cuffed or uncuffed tracheal tubes, laryngeal mask airway, cuffed oropharyngeal airway, tracheostomy and one-lung ventilation devices

The use of a cuffed endotracheal tube should no longer be limited by the age of the child but by his or her clinical condition (e.g. poor lung compliance). To prevent pharyngeal damage, overinflation of the cuff of the laryngeal mask airway should be avoided by inflating it with the minimum volume required to maintain an effective seal and by monitoring intracuff pressure if nitrous oxide is used. Percutaneous tracheostomy in children is still in the experimental stage. New and older devices to perform one-lung ventilation in children are also described.     

An evaluation of the cuffed oropharyngeal airway for elective pediatric anesthesia

STUDY OBJECTIVE: To evaluate the usefulness in pediatric patients of the cuffed oropharyngeal airway (COPA), an airway device with an inflatable cuff around its distal portion, and which provides airway patency in the majority of anesthetized adult patients.Design: Prospective evaluation. SETTING: Pediatric operating room of a tertiary-care medical center. PATIENTS: 50 anesthetized ASA physical status I pediatric patients, under 6 yr of age undergoing elective surgery. INTERVENTIONS: Patients were fitted with a size 7 COPA placed following anesthetic induction. If an adequate airway was not obtained, a size 8 COPA was placed. If an adequate airway was not obtained despite repositioning the size 8, the COPA was considered failed. MEASUREMENTS AND MAIN RESULTS: The ease of insertion and ability to manage the airways were evaluated. Complications were evaluated on insertion, during maintenance, and upon awakening. The ability to positive pressure ventilate via the COPA was assessed. The size 7 COPA obtained an initial fit in 38 (76%) of the patients. Nine patients were managed with a size 8 COPA. The COPA was unsuccessful in 3 (6%) patients. Laryngospasm occurred in three patients. Blood was not visible on any of the COPAs. Positive pressure ventilation was achieved with 30 +/- 7 cm H(2)O pressure. CONCLUSIONS: The results using the COPA in pediatric patients seem to parallel the experience of using larger sizes in adult patients.     

Environmental monitoring of sevoflurane and nitrous oxide using the cuffed oropharyngeal airway

We compared exposure to sevoflurane (SEV) and nitrous oxide (N(2)O) during ventilation using the cuffed oropharyngeal airway (COPA) with waste gas exposure using a conventional face mask (FM) without any additional airways or face straps and with the laryngeal mask airway (LMA). Trace concentrations of SEV and N(2)O were assessed by using a direct reading spectrometer during 33 surgical procedures under general anesthesia. Measurements were made at the patients' mouths and in the anesthesiologists' breathing zones. Mean +/- SD concentrations of SEV and N(2)O measured at the patients' mouths were comparable in the COPA (SEV, 8.1 +/- 12.2 ppm; N(2)O, 213.3 +/- 289.2 ppm) and LMA (SEV, 18.5 +/- 25.8 ppm; N(2)O, 283.4 +/- 361.0 ppm) groups but differed significantly from the FM group (SEV, 46.5 +/- 19.6 ppm; N(2)O, 750.7 +/- 308.3 ppm). These values resulted in a comparable contamination of the anesthesiologists' breathing zones (SEV, 0.5 +/- 0.2 ppm; N(2)O, 5.7 +/- 4.8 ppm) for the COPA group, compared with the LMA group (SEV, 1.0 +/- 0.9 ppm; N(2)O, 12.2 +/- 14.3 ppm). This differed significantly from the FM group (SEV, 2.2 +/- 0.9 ppm; N(2)O, 37.5 +/- 14.3 ppm). We conclude that the use of the COPA during short surgical interventions has an occupational safety comparable to that of the LMA and that both resulted in less contamination through waste anesthetic gases. Therefore, the COPA may be a valuable alternative to the conventional FM. IMPLICATIONS: In this study, we have shown that the occupational exposure to waste anesthetic gases is comparable when using the cuffed oropharyngeal airway (COPA) and the laryngeal mask airway and is increased when using the face mask. Therefore, the COPA may be a valuable alternative to the conventional face mask during short surgical procedures.     

Use of the cuffed oropharyngeal airway for manual ventilation by nonanaesthetists

We studied the use of the cuffed oropharyngeal airway in 100 ASA I and II anaesthetised patients. In the first 50 patients (group A), an experienced anaesthetist inserted the airway. The optimum sizes and cuff volumes for manual ventilation in adult males and females were found to be sizes 11 and 10 with up to 60 ml and 50 ml in each cuff, respectively. Manual ventilation was clinically successful in 49/50 (98%) of these patients. Using these recommendations and following a brief tutorial, a group of 50 nonanaesthetic, basic life-support providers attempted to insert a cuffed oropharyngeal airway and manually ventilate the lungs of a subsequent 50 patients (group NA). Clinically adequate tidal volumes were achieved within 45 s in 47/50 (94%) patients in this group. A persistent leak was present in 21/49 (43%) and 24/47 (51%) of the successful insertions in each group, but this did not affect the ability to ventilate the lungs adequately. The cuffed oropharyngeal airway may offer an effective method of providing adequate ventilation during resuscitation by nonanaesthetic hospital staff.     

Efficacy of the cuffed oropharyngeal airway in spontaneously breathing patients]

A cuffed oropharyngeal airway (COPA) was used in 20 adult patients for airway management under epidural and brachial plexus block supplemented with light general anesthesia. Insertion of a COPA was successful at first attempt in 17 of 20 patients (85%). Sore throat developed in one patient (5%). Aspiration regurgitation, or laryngospasm was not observed. We conclude that a COPA can be an efficient airway device is spontaneously breathing patients under anesthesia.     

Lingual nerve injury after use of a cuffed oropharyngeal airway

The cuffed oropharyngeal airway is a modified Guedel airway and is recommended for anaesthesia in spontaneously breathing patients. To our knowledge this is the first report of transient unilateral lingual nerve palsy after the use of a cuffed oropharyngeal airway to maintain anaesthesia during arthroscopy of an ankle. The aetiology of lingual nerve damage is multifactorial. The possible mechanisms involved include anterior displacement of the mandible during insertion of the cuffed oropharyngeal airway (as in the jaw thrust manoeuvre), compression of the nerve against the mandible, or stretching of the nerve over the hyoglossus by the cuff of the cuffed oropharyngeal airway. We recommend gentle airway manipulation with the use of the cuffed oropharyngeal airway, avoidance of excessive cuff inflation and early recognition of such a complication if it occurs.