i-gel™ supraglottic airway in clinical practice: a prospective observational multicentre study

Background The i-gel™ supraglottic airway device has been studied in randomized controlled studies, but it has not been evaluated in a large prospective patient cohort. Therefore, we performed this prospective multicentre observational study to evaluate success rates, airway leak pressure, risk factors for i-gel failure, and adverse events. Methods With Ethics Committee approval and waiver of patients' consent, data about anaesthesia providers, patient characteristics, and the performance of the i-gel were recorded in five independent hospitals in Switzerland over a period of 24 months. We analysed success rates, leak pressures, adverse events, and risk factors for failure. Results Data from 2049 i-gel uses were analysed. Patients' mean age was 47 (range 6-91) yr. The primary i-gel success rate without changing size was 93%; the overall success rate was 96%. Insertion was deemed very easy or easy in 92%. The mean airway leak pressure was 26 (8) cm H2O. The mean anaesthesia time was 67 (42) min. Risk factors associated with i-gel failure were males (P<0.001), impaired mandibular subluxation (P=0.01), poor dentition (P=0.02), and older age (P<0.01). Adverse events recorded were laryngeal spasms (n=25, 1.2%), blood stained airway devices (n=79, 3.9%), transient nerve damage (n=2, 0.1%), one case of transient vasovagal asystole, and one glottic haematoma. Conclusions The i-gel is a reliable supraglottic airway device failing in <5% and providing high airway leak pressures. Males, impaired mandibular subluxation, poor dentition, and older age are risk factors associated with primary device failure. Serious adverse events are rar

Randomized trial comparing the i-gel™ and Magill tracheal tube with the single-use ILMA™ and ILMA™ tracheal tube for fibreoptic-guided intubation in anaesthetized patients with a predicted difficult airway

Background The i-gel™ is a single-use supraglottic airway device (SAD) that allows fibreoptic-guided tracheal intubation through the device. Until now, no prospective data for this procedure are available. Therefore, in a prospective randomized controlled trial, we evaluated fibreoptic-guided tracheal intubation with a standard Rüsch™ PVC tracheal tube (TT) through the i-gel™ compared with the single-use ILMA™ (sILMA™) TT through the sILMA™ in patients with a predicted difficult airway. Methods With ethics committee approval and written informed consent, 160 patients were randomly assigned to either SAD. After placement of the SAD, a fibreoptic bronchoscope was introduced into the trachea as a railroad for the TT. Primary outcome variable was the first-attempt fibreoptic-guided intubation success rate. Secondary variables included time for insertion and intubation, airway leak pressures, fibreoptic view, and adverse events. Data are presented as mean (sd) or percentages. A P-value of <0.05 was considered statistically significant. Results Fibreoptic-guided intubation was successful at the first attempt in 76 patients (96%) using the i-gel™ and in 71 patients (90%) using the sILMA™ (P=0.21). Most of the failed intubations were rescued by conventional laryngoscopy. Airway leak pressure was higher for the sILMA™. There were no problems during removal of either type of SAD. Conclusions Fibreopic-guided tracheal intubation through the i-gel™ using a standard Rüsch™ Magill TT is successful and an alternative to the sILMA™ with the sILMA™ T

Randomized clinical trial of the i-gel™ and Magill tracheal tube or single-use ILMA™ and ILMA™ tracheal tube for blind intubation in anaesthetized patients with a predicted difficult airway

Background The single-use supraglottic airway device i-gel™ has been described in several case reports as a conduit for intubation, but no prospective data about success rates of blind intubation are available. Therefore, we performed this prospective randomized controlled trial to compare the success rate of blind tracheal intubation with a Magill PVC tube through the i-gel™ with intubation using an sILMA™ PVC tube through the single-use intubating laryngeal mask airway (sILMA™). Methods With ethics committee approval and written informed consent, 80 patients with predictors of a difficult airway were computer randomized to either supraglottic airway device (SAD). The corresponding tracheal tube (TT) was introduced through the SAD under fibreoptic visualization but without fibreoptic guidance. Primary outcome was blind intubation success rate. Times, airway leak pressure, fibreoptic view, and adverse events were recorded. To control for the influence of the TT, we compared data from 40 patients described in an accompanying study (sILMA™ with Magill TT and i-gel™ with sILMA™ TT). Results Blind intubation success rate through the sILMA™ (69%) was higher than with the i-gel™ (15%, P<0.001). Data from the other patient group excluded the TT type as the primary cause for the difference in success rate. Removal of SADs was without problems with no difference between the type of SAD. Conclusions Blind tracheal intubation using the sILMA™ tube through the sILMA™ is much more successful than blind intubation with a Magill PVC tube through the i-gel™. Because of its low success rate, we would not recommend blind intubation through the i-gel

Ultrasound-guided percutaneous tracheal puncture: a computer-tomographic controlled study in cadavers

Background Ultrasound-guided techniques are increasingly used in anaesthetic practice to identify tissues beneath the skin and to increase the accuracy of placement of needles close to targeted structures. To examine ultrasound's usefulness for dilatational tracheostomy, we performed ultrasound-guided tracheal punctures in human cadavers followed by computer-tomographic (CT) control. Methods The trachea of nine cadavers was punctured using an in-plane approach with a longitudinal ultrasound visualization of the trachea. As soon as a loss of resistance was felt, or air/fluid could be aspirated into the attached syringe, the syringe was disconnected and the ultrasound transducer set aside. Thereafter, a cricothyroidotomy guidewire was inserted through the needle into the trachea. The needle was then removed, leaving the wire in place and a control CT imaging of the neck and the chest was performed. Primary outcome was successful wire insertion into the trachea. Results Tracheal puncture and wire insertion was successful in eight of nine cadavers at the first attempt and in one at the second attempt (total of 10 puncture attempts, nine successful). In eight of nine successfully inserted wires, the wire was placed on the defined midline. Conclusions Ultrasound guidance can facilitate successful tracheal puncture. However, combining an in-plane approach with a longitudinal ultrasound visualization of the trachea neither guarantees an exact midline puncture nor allows detection of a misplaced guidewir

Five-year audit of adherence to an anaesthesia pre-induction checklist.

Although patient safety related to airway management has improved substantially over the last few decades, life-threatening events still occur. Technical skills, clinical expertise and human factors contribute to successful airway management. Checklists aim to improve safety by providing a structured approach to equipment, personnel and decision-making. This audit investigates adherence to our institution's airway checklist from 1 June 2016 to 31 May 2021. Inclusion criteria were procedures requiring airway management and we excluded all procedures performed solely under regional anaesthesia, sedation without airway management or paediatric and cardiovascular surgery. The primary outcome was the proportion of wholly performed pre-induction checklists. Secondary outcomes were the pattern of adherence over the 5 years well as details of airway management, including: airway management difficulties; time and location of induction; anaesthesia teams in operating theatres (including teams for different surgical specialities); non-operating theatre and emergency procedures; type of anaesthesia (general or combined); and urgency of the procedure. In total, 95,946 procedures were included. In 57.3%, anaesthesia pre-induction checklists were completed. Over the 5 years after implementation, adherence improved from 48.3% to 66.7% (p < 0.001). Anticipated and unanticipated airway management difficulties (e.g. facemask ventilation, supraglottic airway device or intubation) defined by the handling anaesthetist were encountered in 4.2% of all procedures. Completion of the checklist differed depending on the time of day (61.3% during the day vs. 35.0% during the night, p < 0.001). Completion also differed depending on location (66.8% in operating theatres vs. 41.0% for non-operating theatre anaesthesia, p < 0.001) and urgency of procedure (65.4% in non-emergencies vs. 35.4% in emergencies, p < 0.001). A mixed-effect model indicated that urgency of procedure is a strong predictor for adherence, with emergency cases having lower adherence (OR 0.58, 95%CI 0.49-0.68, p < 0.001). In conclusion, over 5 years, a significant increase in adherence to an anaesthesia pre-induction checklist was found, and areas for further improvement (e.g. emergencies, non-operating room procedures, night-time procedures) were identified

Parameters influencing the size of chitosan-TPP nano- and microparticles

Chitosan nanoparticles, produced by ionic gelation, are among the most intensely studied nanosystems for drug delivery. However, a lack of inter-laboratory reproducibility and a poor physicochemical understanding of the process of particle formation have been slowing their potential market applications. To address these shortcomings, the current study presents a systematic analysis of the main polymer factors affecting the nanoparticle formation driven by an initial screening using systematic statistical Design of Experiments (DoE). In summary, we found that for a given chitosan to TPP molar ratio, the average hydrodynamic diameter of the particles formed is strongly dependent on the initial chitosan concentration. The degree of acetylation of the chitosan was found to be the second most important factor involved in the system's ability to form particles. Interestingly, viscosimetry studies indicated that the particle formation and the average hydrodynamic diameter of the particles formed were highly dependent on the presence or absence of salts in the medium. In conclusion, we found that by controlling two simple factors of the polymer solution, namely its initial concentration and its solvent environment, it is feasible to control in a reproducible manner the production and characteristics of chitosan particles ranging in size from nano- to micrometres

Pharmacogenetics in palliative care

Response to analgesics, anticancer pharmacotherapy and pharmacotherapy of other cancer related symptoms vary broadly between individuals. Age, disease, comorbidities, concomitant medication, organ function and patients' compliance may partly explain the differences. However, the focus of ongoing research has shifted towards genomic variants of phase I and II drug metabolizing enzymes with one important goal being an individual dose adjustment according to a patient's genotype. Polymorphisms of the cytochrome P 450 2D6 influence the metabolism of many drugs including the analgesics codeine, tramadol, hydrocodone and oxycodone, as well as the metabolism of tricyclic antidepressants and the anticancer drug tamoxifen. Other candidate genes such as (opioid)-receptors, transporters and other molecules important for pharmacotherapy in pain management are discussed. Although pharmacogenetics as a diagnostic tool has the potential to improve patient therapy, study results are often equivocal and limited by small sample sizes and often by their retrospective design. Well designed studies are needed to demonstrate superiority of pharmoacogenetics to conventional dosing regimes

Randomized trial comparing the i-gel™ and Magill tracheal tube with the single-use ILMA™ and ILMA™ tracheal tube for fibreoptic-guided intubation in anaesthetized patients with a predicted difficult airway

The i-gel™ is a single-use supraglottic airway device (SAD) that allows fibreoptic-guided tracheal intubation through the device. Until now, no prospective data for this procedure are available. Therefore, in a prospective randomized controlled trial, we evaluated fibreoptic-guided tracheal intubation with a standard Rüsch™ PVC tracheal tube (TT) through the i-gel™ compared with the single-use ILMA™ (sILMA™) TT through the sILMA™ in patients with a predicted difficult airway