The PAxpress is an effective ventilatory device but has an 18% failure rate for flexible lightwand-guided tracheal intubation in anesthetized paralyzed patients

Airway management in the obese patient

Airway management is a major factor underlying morbidity and mortality in the obese population. The validity of anthropomorphic prediction model in assessing a difficult airway is less accurate compared with lean subjects. Preoperative evaluation and anticipation of potential complications are critical for safe and successful intubation. Application of noninvasive positive airway pressure can prevent atelectasis and improve oxygenation during the anesthetic induction as well during the postoperative period and after liberation from mechanical ventilation. When performed by trained operators, bedside percutaneous dilatation tracheostomy in obese patients has a safety profile comparable to surgical tracheostomy but provides advantages including ease of performance and lesser cost, and obviates transporting a critically ill patient outside the intensive care unit.

Assessment of manoeuvres required for successful blind tracheal intubation through the PAXpress

A PAXpress (Vital Signs Inc., Barnham, UK) airway device was placed in 50 adult ASA grade I and II patients undergoing elective surgery under general anaesthesia. The alignment of the PAXpress to the larynx was scored fibreoptically. The patients were then intubated blindly through the PAXpress and the adjusting manoeuvres required for successful intubation and complications of intubation observed. Insertion of the PAXpress was successful in all patients, and intubation was successful in 42 (84%) patients. Eleven patients were intubated in the neutral position, seven with a flexion manoeuvre and 24 with an extension manoeuvre. Intubation was successful in 17/20, 18/20, 6/8 and 1/2 of patients with a fibreoptic alignment score of 1, 2, 3 and 4, respectively. When the fibreoptic alignment score was between 2 and 4 intubation was achieved predominantly with the extension manoeuvre (20/30, 66%) rather than the flexion manoeuvre (1/30, 3%) or the neutral position (5/30, 16%). Blood staining was observed in 20 patients. We conclude that blind tracheal intubation through PAXpress has a moderately good success rate and a high incidence of mucosal trauma. 'Extension' is the predominant adjusting manoeuvre required for blind tracheal intubation, especially when the alignment of the PAXpress to the larynx is poor.

Performance of the PAX press ™ vs the ProSeal™ laryngeal mask airway during general anesthesia

PURPOSE

The PAxpress (PAx) is a relatively new pharyngeal airway device that is easily inserted and effective in routine airway management. A prospective, randomized study was undertaken to compare the PAx with the ProSeal laryngeal mask airway (PLMA) during anesthesia with positive pressure ventilation.

METHODS

One hundred adult patients scheduled for elective surgery under general anesthesia were randomized to airway management with either the PAx (n=50) or the PLMA (n=50). All patients swallowed a methylene blue capsule before anesthesia. After insertion, leak and inspiratory pressures were measured. Fibrescopy was used to view the glottis. Devices were inspected for blood or methylene blue staining upon removal at the end of surgery. An interview was conducted postoperatively to evaluate the occurrence of sore throat, dysphagia and dysphonia.

RESULTS

Insertion time was longer for the PAx than for the PLMA (52 +/- 44s vs 34 +/- 23 sec; P=0.003). Leak pressure was lower while peak inspiratory pressures, and EtCO2 values were higher (P=0.016; 0.027 and 0.04 respectively) with the PAx. Both devices provided comparable fibreoptic viewing of the glottis. There were no differences with respect to the incidence or pattern of blue stains upon removal. Blood was seen more often on the PAx (58% vs 19%) and dysphagia was also more frequent and severe with the PAx.

CONCLUSION

In comparison with the PLMA, PAx insertion time is longer and the ventilatory characteristics of this new device may be marginally inferior. The PAx is also more traumatic and is associated with more postoperative discomfort compared to the PLMA.

A Proposed Classification and Scoring System for Supraglottic Sealing Airways: A Brief Review

We provide an approach to evaluating sealing supraglottic airways by using a classification based on a sealing mechanism. Three main sealing mechanisms are identified, thus defining three groups: cuffed perilaryngeal sealers, cuffed pharyngeal sealers, and uncuffed anatomically preshaped sealers. We provide a brief overview of supraglottic airways and present a scoring system that is relevant to particular requirements. Scoring airways for routine applications is the example provided.