An Evaluation of Thyromental Distance-based Method or Weight-based Method in Determining the Size of the Laryngeal Mask Airway Supreme: A Randomized Controlled Study

Assessment of Neck Characteristics for Laryngeal Mask Airway Size Selection in Patients Who Underwent an Elective Ocular Surgery; A Cross-Sectional Study

Objective:

To investigate the neck features for laryngeal mask airway (LMA) size selection.

Methods:

This cross-sectional study was conducted on 160 patients referred for elective surgeries to Feiz Hospital affiliated with Isfahan University of Medical Sciences, Isfahan, Iran (April 2016 to September 2018). Patients underwent ventilation using LMA whose size was determined through a weighted-based approach. All of the patients’ neck characteristics including circumference, thyromental distance, and opening mouth were measured. Ventilation factors were recorded including numbers of attempts for successful LMA insertion, quality of ventilation, and sealing.

Results:

Neck circumference and thyromental distance were significantly different with the size of LMA (p<0.0001 and p=0.005, respectively), but not mouth opening (p=0.21). Neck circumference, thyromental distance, and mouth opening were not significantly different with the times of insertion attempts (p>0.05 for all comparisons). However, the thyromental distance was significantly different with the quality ventilation status (p<0.0001). The total assessment of insertion attempts, ventilation efficacy and sealing was significantly different with the neck circumference (p<0.001), but thyromental distance did not show a significant difference (p>0.05).

Conclusion:

Findings demonstrated that neck circumference might be considered as an appropriate indicator for the selection of LMA size but neither the thyromental distance nor mouth opening. Further studies with a larger sample size are strongly recommended.

Clinical Performance Comparison of LMA Protector™ Cuff Pilot™ and LMA Supreme™ When Used in Anesthetized, Non-paralyzed Patients

Introduction

The advancement of supraglottic airways (SGAs) has eased airway management, especially for anesthetists. There were functional improvements implemented to the newer SGA. We aim to assess the clinical performance of laryngeal mask airway (LMA) Protector™ Cuff Pilot™ (Teleflex Inc., Wayne, Pennsylvania, USA) against LMA Supreme™ (Teleflex Inc., Wayne, Pennsylvania, USA), in terms of oropharyngeal leak pressure (OLP), successful insertion attempts, mean insertion time, ease of gastric tube insertion, laryngeal view, and incidence of sore throat among anesthetized, non-paralyzed patients undergoing general anesthesia.

Methods

In this prospective single-blinded study, 60 patients were randomized to use either LMA Protector™ Cuff Pilot™ or LMA Supreme™. Both groups received standard monitoring and induction regimes. Post-insertion, a bronchoscope was used to verify its position. A gastric tube was inserted and OLP was measured. Patients were assessed during the post-operative period for sore throats.

Results

LMA Protector™ Cuff Pilot™ was comparable to LMA Supreme™ in terms of mean OLP (30.72±8.60 vs 27.23±8.09 cmH₂O, P = 0.114), first successful attempt (P = 0.312), mean insertion time (27.72±9.45 vs 24.37±6.46 seconds, P = 0.116), and grade 1 laryngeal view (51.7% vs 36.7%, P = 0.244). At first attempt, LMA Protector™ Cuff Pilot™ had a lower success rate of gastric tube insertion than LMA Supreme™ (55.17% vs 96.67%, P <0.001). The incidence of the blood-stained device and sore throat post-operatively were comparable between the two groups.

Conclusion

LMA Protector™ Cuff Pilot™ was comparable to LMA Supreme™ in terms of overall clinical performance, except for the first successful gastric tube insertion. Improvements should be made to the gastric channel for easier gastric tube insertion in the LMA Protector™ Cuff Pilot™.

Naringin protects against steroid‑induced avascular necrosis of the femoral head through upregulation of PPARγ and activation of the Notch signaling pathway

Naringin, a flavonoid, is the effective pharmaceutical ingredient of drynaria, with the effects of healing fractures, strengthening bones and promoting kidney function. The aim of the present study was to investigate the potential effect of naringin on steroid‑induced avascular necrosis of the femoral head (SANFH). Treatment with naringin markedly protected against the steroid‑induced decrease in serum osteocalcin levels, and the rate of osteonecrosis in a model of SANFH. In addition, naringin decreased the total cholesterol and low density lipoprotein/high density lipoprotein ratio in the SANFH rabbit. It was observed that naringin markedly inhibited caspase‑3 activity, increased runt‑related transcription factor 2 and transcription factor sp7 mRNA expression, promoted alkaline phosphatase activity and upregulated collagen I, peroxisome proliferator‑activated receptor (PPAR) γ2, neurogenic locus notch homolog protein (Notch), β‑catenin and phosphorylated‑Rac‑α serine/threonine protein kinase protein expression in the SANFH rabbit. The results of the present study demonstrated that naringin protects against SANFH through upregulation of PPARγ2 and activation of the Notch signaling pathway, and may be a useful addition to the treatment options for diseases of the femoral head.

Comparison of actual and ideal body weight for selection of appropriate size of ProSeal™ laryngeal mask airway in overweight and obese patients: A prospective, randomised study

BACKGROUND AND AIMS

The ProSeal™ laryngeal mask airway (PLMA) has advantages of providing better cuff seal and the presence of a gastric drain tube. The manufacturer recommends actual body weight (ABW) for size selection. Pharyngeal area reduces with increase in body mass index (BMI); hence, in overweight patients, PLMA selected on ABW may not fit well. We hypothesised that the ideal body weight (IBW) would be more appropriate in size selection of PLMA.

METHODS

This randomised, single-blind study included 124 patients of 20-60 years and American Society of Anesthesiologists Class I-II, with BMI >25. Patients were randomly divided into two groups. In Group ABW, PLMA was selected based on ABW (62 patients) and in Group IBW, PLMA was selected based on IBW (62 patients). The primary outcome was the first-attempt insertion success rate. Oropharyngeal air leaks, gastric air leaks, drain tube air leaks, insertion difficulty scores and postoperative complications were assessed. Fibre-optic view (Grade I-IV) was assessed for proper placement by a blinded assessor. Statistical analyses were performed using Chi-square test or Fisher's exact test.

RESULTS

First-attempt insertion success rate and overall insertion success rates were similar in both the groups. Group IBW patients had significantly less resistance during insertion, lower peak airway pressures, successful nasogastric tube insertions, better fibre-optic views and less post-operative complications. Oropharyngeal leak pressure and instrumentation used for insertion were comparable.

CONCLUSION

IBW is preferable for the size selection of the PLMA in overweight and obese patients compared to the ABW.