I-gel Versus LMA-Fastrach Supraglottic Airway for Flexible Bronchoscope-Guided Tracheal Intubation Using a Parker (GlideRite) Endotracheal Tube: A Randomized Controlled Trial.

BACKGROUND: The I-gel (IG) supraglottic airway device is a reliable way to establish an airway. Its large ventilation lumen allows for easy passage of an endotracheal tube. With the use of a flexible bronchoscope, the IG offers a good visualization of the laryngeal inlet. This prospective randomized study aims to compare the success rate of flexible bronchoscope-guided tracheal intubation using either the IG or the LMA-Fastrach (FT) laryngeal masks. METHODS: One hundred twenty patients requiring general anesthesia were randomized to 1 of the 2 study groups: IG or FT. After anesthesia induction, the assigned laryngeal mask was inserted to obtain adequate ventilation. We then proceeded to a flexible bronchoscope-guided intubation through the supraglottic device. Tracheal intubation and laryngeal mask insertion success rates were noted, as well as the time required for these manipulations. The view of the laryngeal inlet was graded for each intubation attempt. RESULTS: Sixty patients were assigned to each study group. The intubation success rates were similar between the IG and the FT groups (100 % vs 95.0 % at first attempt; P = 0.12). The times required for tracheal intubation were significantly lower in the IG group (30 ± 11 seconds vs 50 ± 21 seconds; P < 0.0001). Glottic visualization was better in the IG group, with a significantly higher percentage of grade 1 visualization (63.3% vs 3.3%; P < 0.0001) and a lower percentage of grade 3 visualization (1.7% vs 60.0%; P < 0.0001), than that in the FT group. CONCLUSIONS: The use of the IG supraglottic airway device as a conduit for flexible bronchoscope-guided tracheal intubation results in a success rate equivalent to the use of the LMA-FT. However, the IG allows for shorter intubation times and a better visualization of the glottic opening compared with the LMA-FT.

A comparison of two doses of mannitol on brain relaxation during supratentorial brain tumor craniotomy: a randomized trial.

BACKGROUND: Twenty percent mannitol is widely used to reduce brain bulk and facilitate the surgical approach in intracranial surgery. However, a dose-response relationship has not yet been established. In this study, we compared the effects of 0.7 and 1.4 g·kg(-1) mannitol on brain relaxation during elective supratentorial brain tumor surgery. METHODS: In this prospective, randomized, double-blind study, we enrolled 80 patients undergoing supratentorial craniotomy for tumor resection. Patients were assigned to receive 0.7 g·kg(-1) (group L) or 1.4 g·kg(-1) (group H) of 20% mannitol at surgical incision. Brain relaxation was assessed immediately after opening of the dura on a scale ranging from 1 to 4 (1 = perfectly relaxed, 2 = satisfactorily relaxed, 3 = firm brain, 4 = bulging brain). RESULTS: There was no significant difference between the 2 groups regarding age, sex, body mass index, and brain tumor localization or size. In group L 52.5% of patients and in group H 77.5% of patients presented a midline shift (P = 0.03). The median scores of brain relaxation (interquantile range) were 2.0 (1.75-3) and 2.0 (1-3) (P = 0.16 for patients in group L and H, respectively). We then used a proportional odds model to adjust for this unbalanced distribution and to assess the group effect (low-dose versus high-dose mannitol) on brain relaxation scores. When adjusted for the presence of midline shift, the use of a higher dose of mannitol resulted in an odds ratio of 2.5 (P = 0.03). This indicates that, considering the effect of a midline shift, the odds of having a 1-level improvement in relaxation score in patients who received a higher dose of mannitol (group H) was 2.5 times as large as the odds for the low-dose group. The odds ratio of 0.29 (P = 0.007) for the midline shift indicates that its occurrence was associated with a higher probability of a lower relaxation score, on average. CONCLUSION: In this study, we show that 1.4 g·kg(-1) of 20% mannitol results in equivalent brain relaxation scores as 0.7 g·kg(-1) in patients undergoing craniotomy for supratentorial brain tumor. When corrected for the presence of midline shift, this study reveals that patients in the high-dose group had significantly more chances of obtaining a better relaxation score compared with the lower-dose group.

Tracheal intubation through the I-gel™ supraglottic airway versus the LMA Fastrach™: a randomized controlled trial.

BACKGROUND: The i-gel™ is a supraglottic airway device not requiring inflation of a cuff for lung ventilation. Its design allows for unobstructed passage of a tracheal tube and previous studies have demonstrated a favorable alignment with the glottic inlet. In this prospective randomized study, we compared the success rate of blind tracheal intubation using the i-gel and the laryngeal mask airway (LMA) Fastrach™. METHODS: One hundred sixty patients requiring general anesthesia and airway management were randomized to tracheal intubation using the i-gel or the LMA Fastrach. After induction of general anesthesia, the allocated device was inserted and adequate lung ventilation was confirmed. Blind tracheal intubation was then attempted. First attempt and overall tracheal intubation success rates were evaluated and tracheal intubation times were measured. RESULTS: Eighty patients were recruited in each study group. Successful tracheal intubation was obtained on the first attempt in 69% of patients with the i-gel and 74% of patients with the LMA Fastrach (95% confidence interval [CI] of difference, -9% to 19%, P = 0.60). The overall intubation success rate was lower using the i-gel than it was using the LMA Fastrach (73% vs 91%, 95% CI of difference, 7% to 31%, P < 0.0001). CONCLUSIONS: On first attempts, successful blind tracheal intubation was obtained at comparable rates using the i-gel and the LMA Fastrach. However, when the first attempt was unsuccessful, subsequent attempts through the i-gel did not significantly increase tracheal intubation success rate. The LMA Fastrach yielded a higher overall intubation success rate.

A comparison of propofol and remifentanil target-controlled infusions to facilitate fiberoptic nasotracheal intubation.

INTRODUCTION: Successful fiberoptic intubation requires both patient comfort and good intubating conditions. In this study we compared the efficacy and ease of titration of propofol (P) and remifentanil (R) target-controlled infusions (TCI) during fiberoptic intubation. METHODS: Sixty patients requiring fiberoptic nasotracheal intubation were randomized to receive (P) or (R) effect-site TCI. After topical anesthesia, TCI was set to 2.5 microg/mL (P) or 1.5 ng/mL (R) then titrated by 1 microg/mL (P) or 0.5 ng/mL (R) increments according to patient reactions. Targets and level of sedation were recorded at each step as well as total dose, number of adjustments, intubating conditions, discomfort, and recall assessed after surgery. RESULTS: Intubation duration, success rate, and number of increments did not differ between groups. Intubating conditions were good in both groups, with a final target of 3.9 +/- 1.4 microg/mL (P) or 2.4 +/- 0.8 ng/mL (R) (total dose 142 +/- 55 mg and 77 +/- 27 microg, respectively). There was no difference in minimal SpO(2) and maximal end-tidal CO(2) after intubation. No laryngospasm or significant hemodynamic instability was observed. There was one major hypoxemia due to obstructive apnea in group P. Patients in group P were significantly more sedated and less cooperative. Recall was more frequent in group R, whereas pain scores were equally low in both groups. CONCLUSION: Both R and P TCI can be rapidly titrated to achieve good intubating conditions and patient comfort. R allows for more patient cooperation, making it safer when spontaneous ventilation is paramount.

Performance of the PAxpress 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.