Comparison of the McGRATHTM Video Laryngoscope and Macintosh Laryngoscope for Orotracheal Intubation in a Simulated Difficult Airway Scenario: An Open-Label, Randomized Clinical Trial.

Background and Objectives: Difficult intubation, which may be encountered unexpectedly during anesthesia, can increase patients' morbidity and mortality. The McGRATH video laryngoscope is known to provide improved laryngeal visibility in patients with difficult or normal airways. The purpose of this study was to evaluate the efficacy of the McGRATH video laryngoscope for orotracheal intubation compared with that of conventional Macintosh laryngoscopes in simulated difficult airway scenarios. Materials and Methods: In this randomized controlled trial, patients who were scheduled for surgery under general anesthesia requiring orotracheal intubation were assigned to the Macintosh laryngoscope (n = 50) or McGRATH video laryngoscope (n = 45) groups. In this study, to create a simulated difficult airway condition, the subjects performed manual in-line stabilization and applied a soft cervical collar. The primary outcome was the rate of successful intubation within 30 s. The time required for an intubation, glottis grade, intubation difficulty scale (IDS score), the subjective ease of intubation, and optimal external laryngeal manipulation (OLEM) were evaluated. In addition, complications caused by each blade were investigated. Results: The intubation success rate within 30 s was not significantly different between the two groups (44 (88.0%) vs. 36 (80.0%), p = 0.286). The glottic grade was better in the McGRATH group than in the Macintosh group (p = 0.029), but neither the intubation time (26.3 ± 8.2 s vs. 24.2 ± 5.0 s, p = 0.134) nor the rates of oral bleeding (2 (4.0%) vs. 0 (0.0%)) and tooth injury (0 (0.0%) vs. 1 (2.2%)) were significantly different between the two groups. Conclusions: The use of the McGRATH video laryngoscope did not improve the intubation success rate or shorten the intubation time. However, the McGRATH video laryngoscope provided a better glottis view than the conventional Macintosh laryngoscope in patients with a simulated difficult airway.

Comparison of Pentax Airway Scope and Macintosh laryngoscope for orotracheal intubation in children: A randomised non-inferiority trial.

BACKGROUND: Pentax Airway Scope (AWS) is a recently developed videolaryngoscope for use in both normal and difficult airways, yet its use in paediatric patients has not been established. The purpose of this study was to evaluate the efficacy of the Pentax AWS regarding intubation time, laryngeal view and ease of intubation in paediatric patients with normal airway, compared to Macintosh laryngoscope. METHOD: A total of 136 paediatric patients aged 1-10 with American Society of Anaesthesiologists physical status I or II undergoing general anaesthesia were randomly allocated into two groups: Macintosh laryngoscope (n = 68) and Pentax Airway Scope (n = 68). Primary outcome was intubation time. Cormack-Lehane laryngeal view grade, application of optimal laryngeal external manipulation, intubation difficulty scale, intubation failure rate and adverse events were also measured. RESULT: No significant difference was observed between the two groups regarding intubation time (P = 0.713). As for the laryngeal view grade, the Pentax group resulted in lower graded cases compared to the Macintosh group (P = 0.000). No optimal laryngeal external manipulation application was required in the Pentax group. Intubation difficulty scale resulted in lower values for Pentax group (P = 0.001). Failure rate was not different between the two groups (P = 0.619). There were significantly more teeth injury cases in the Pentax group than Macintosh group (P = 0.042). CONCLUSION: Pentax Airway Scope provided similar intubation time and success rate, while improving laryngeal view, compared to Macintosh laryngoscopy in children with normal airway. When using Pentax AWS in children, however, the risk of teeth injury may increase.

McGrath Video Laryngoscopy Facilitates Routine Nasotracheal Intubation in Patients Undergoing Oral and Maxillofacial Surgery: A Comparison With Macintosh Laryngoscopy.

PURPOSE: The McGrath video laryngoscope (VL) offers excellent laryngoscopic views and increases the success rate of orotracheal intubation in patients with normal and difficult airways. The purpose of this randomized controlled trial was to compare the McGrath VL with the Macintosh laryngoscope to investigate the efficacy of the McGrath VL for routine nasotracheal intubation in patients with an expected normal airway. MATERIALS AND METHODS: To address the research purpose, the efficacy of the McGrath VL for routine nasotracheal intubation was compared with that of the Macintosh laryngoscope. The predictor variable was the laryngoscopic technique (McGrath VL vs Macintosh laryngoscope). The outcome variables were the time to successful intubation, laryngoscopic views before and after optimal external laryngeal manipulation (OELM), use of Magill forceps, ease of intubation, and severity of oropharyngeal bleeding. RESULTS: Data from 35 patients undergoing oral and maxillofacial surgery were assessed. The time to intubation was 10.5 seconds shorter in the McGrath group than in the Macintosh group (34.4 ± 13.7 vs 44.9 ± 15.6 seconds; P = .004). The incidence of grade 1 glottic view before OELM was higher in the McGrath group than in the Macintosh group (83 vs 57%; P = .019). The frequency of Magill forceps use was lower in the McGrath group than in the Macintosh group (6 vs 34%; P = .003). CONCLUSION: McGrath VL facilitates routine nasotracheal intubation in expected normal airways by providing a shorter intubation time and better laryngoscopic views compared with the Macintosh laryngoscope.

Effect of High-Flow Nasal Oxygenation on Gastric Insufflation in Patients Undergoing Laryngeal Microsurgery under Tubeless General Anesthesia with Neuromuscular Blockade.

BACKGROUND: High-flow nasal oxygenation is an oxygen delivery method by which high concentrations of heated humidified oxygen are supplied via the nasal cavity. This study aimed to investigate the effect of high-flow nasal oxygenation on gastric volume change in adult patients undergoing laryngeal microsurgery under tubeless general anesthesia with neuromuscular blockade. METHODS: Patients aged 19-80 years with an American Society of Anesthesiologists physical status 1 or 2 who were scheduled to undergo laryngoscopic surgery under general anesthesia were recruited. Patients received high-flow nasal oxygenation therapy at 70 L/min during surgery under general anesthesia with neuromuscular blockade. The cross-sectional area of the gastric antrum was measured via ultrasound in the right lateral position before and after high-flow nasal oxygenation, and the gastric volume was calculated. The duration of apnea, i.e., the duration of administration of high-flow nasal oxygenation in the paralyzed state, was also recorded. RESULTS: Of the 45 patients enrolled, 44 completed the study. There were no significant differences in the antral cross-sectional area in the right lateral position, gastric volume, and gastric volume per kg between before and after high-flow nasal oxygenation application. The median duration of apnea was 15 (interquartile range, 14-22) min. CONCLUSION: High-flow nasal oxygenation at 70 L/min during apnea with the mouth open did not influence the gastric volume in patients undergoing laryngeal microsurgery under tubeless general anesthesia with neuromuscular blockade.

Behavioral and healthcare-associated risk factors for chronic hepatitis C virus infection in Korea.

The risk factors related to hepatitis C virus (HCV) infection showed geographic and temporal differences. We investigated HCV-related risk factors in Korea where intravenous drug use (IVDU) is uncommon. The HCV-related risk factors were investigated in a prospective, multicenter chronic HCV cohort (n = 711) using a standardized questionnaire in four university hospitals. The results were compared with those of 206 patients with chronic liver diseases not related to either of HCV or hepatitis B virus infection (comparison group). The IVDU was found in 3.9% and remote blood transfusion (≥ 20 yr ago) in 18.3% in HCV cohort group, while that in comparison group was in none and 5.3%, respectively. In a multivariate logistic analysis, transfusion in the remote past (odds ratio [OR], 2.99), needle stick injury (OR, 4.72), surgery (OR, 1.89), dental procedures (OR, 2.96), tattooing (OR, 2.07), and multiple sexual partners (2-3 persons; OR, 2.14, ≥ 4 persons; OR, 3.19), were independent risk factors for HCV infection. In conclusion, the major risk factors for HCV infection in Korea are mostly related to conventional or alterative healthcare procedures such as blood transfusion in the remote past, needle stick injury, surgery, dental procedure, and tattooing although multiple sex partners or IVDU plays a minor role.

[Comparison between conventional 4 L polyethylene glycol and combination of 2 L polyethylene glycol and sodium phosphate solution as colonoscopy preparation].

BACKGROUND/AIMS: Effective bowel preparation is essential for accurate diagnosis of colon disease. We investigated efficacy and safety of 2 L polyethylene glycol (PEG) solution with 90 mL sodium phosphate (NaP) solution compared with 4 L PEG method. METHODS: Between August 2009 and April 2010, 526 patients were enrolled who visited Seoul National University Bundang Hospital for colonoscopy. We allocated 249 patients to PEG 4 L group and 277 patients to PEG 2 L with NaP 90 mL group. Detailed questionnaires were performed to investigate compliance, satisfaction and preference of each method. Bowel preparation quality and segmental quality were evaluated. Success was defined as cecal intubation time less than 20 minutes without any help of supervisors. RESULTS: Both groups revealed almost the same baseline characteristics except the experience of operation. PEG 4 L group's compliance was lower than PEG 2 L with NaP 90 mL group. Success rate and cecal intubation time was not different between two groups. Overall bowel preparation quality of PEG 2 L with NaP 90 mL group was better than PEG 4 L group. Segmental bowel preparation quality of PEG 2 L with NaP 90 mL group was also better than PEG 4 L group in all segments, especially right side colon. Occurrence of hyperphosphatemia was higher in PEG 2 L with NaP 90 mL group than PEG 4 L group. However, significant adverse event was not reported. CONCLUSIONS: PEG 2 L with NaP 90 mL method seems to be more effective bowel preparation than PEG 4 L method.

Comparison of McGrath, Pentax, and Macintosh laryngoscope in normal and cervical immobilized manikin by novices: a randomized crossover trial.

BACKGROUND: The aim of this study was to compare tracheal intubation performance regarding the time to intubation, glottic view, difficulty, and dental click, by novices using McGrath videolaryngoscope (VL), Pentax Airway Scope (AWS) and Macintosh laryngoscope in normal and cervical immobilized manikin models. METHODS: Thirty-five anesthesia nurses without previous intubation experience were recruited. Participants performed endotracheal intubation in a manikin model at two simulated neck positions (normal and fixed neck via cervical immobilization), using three different devices three times each. Performance parameters included intubation time, success rate of intubation, Cormack Lehane laryngoscope grading, dental click, and subjective difficulty score. RESULTS: Intubation time and success rate during first attempt were not significantly different between the 3 groups in normal airway manikin. In the cervical immobilized manikin, the intubation time was shorter (p = 0.012), and the success rate with the first attempt was significantly higher (p < 0.001) when using McGrath VL and Pentax AWS compared with Macintosh laryngoscope. Both VLs showed less difficulty score (p < 0.001) and more Cormack Lehane grade I (p < 0.001) in both scenarios. The incidence of dental clicks was higher with Macintosh laryngoscope compared with McGrath VL in cervical immobilized airway (p < 0.001). CONCLUSIONS: McGrath VL and Pentax AWS did not show clinically significant decrease in intubation time, however, they achieved higher first attempt success rate, easier intubation and better glottis view compared with Macintosh laryngoscope by novices in a cervical immobilized manikin model. McGrath VL may reduce the risk of dental injury compared with Macintosh laryngoscope in cervical immobilized scenario. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03161730), May 22, 2017 https://clinicaltrials.gov/ct2/hom.

Effect of sex differences in remifentanil requirements for the insertion of a laryngeal mask airway during propofol anesthesia: A prospective randomized trial.

BACKGROUND: Remifentanil can improve insertion of a laryngeal mask airway (LMA) during induction with propofol. Recently, it has been suggested that there is a sex difference in opioid requirements for this procedure. The purposes of this study were to determine the effective effect-site concentration (Ce) of remifentanil for the facilitation of LMA insertion in male and female patients during propofol anesthesia without neuromuscular blockade and to evaluate whether there are sex differences in the Ce of remifentanil required for successful LMA insertion. METHODS: Forty-eight patients (24 male, 24 female) with American Society of Anesthesiologists physical status 1 or 2, aged 20 to 60 years, scheduled for minor orthopedic surgery under general anesthesia were enrolled. Anesthesia was induced by target-controlled infusion (TCI) of propofol and remifentanil. The target Ce of propofol was 5 µg/mL initially and was reduced to 3.5 µg/mL after loss of consciousness. The Ce of remifentanil given to each patient was determined by the response of the previously tested patient using 0.5 ng/mL as a step size. The 1st patient was tested at a Ce of 3.0 ng/mL of remifentanil. Successful LMA insertion was defined as smooth insertion without patient movement or significant resistance to mouth opening. RESULTS: The effective Ce of remifentanil required for successful LMA insertion on 50% of occasions (effective effect-site concentration for 50% [EC50]) as estimated by Dixon method was significantly lower in women (2.18 ±â€Š0.35 ng/mL) than in men (2.82 ±â€Š0.53 ng/mL) (P = 0.02). Using the isotonic regression method, the effective Ce of remifentanil required for successful LMA insertion on 95% of occasions (EC95) (95% confidence interval [CI]) was significantly lower in women (3.38 [3.0-3.48] ng/mL) than in men (3.94 [3.80-3.98] ng/mL). CONCLUSION: The Ce of remifentanil required to facilitate successful LMA insertion is higher during propofol induction by TCI in men than in women. When using remifentanil for LMA insertion, patient sex should be taken into account for appropriate dosing.

Predicted EC50 and EC95 of Remifentanil for Smooth Removal of a Laryngeal Mask Airway Under Propofol Anesthesia.

PURPOSE: The purpose of this study was to determine the effect-site concentration (Ce) of remifentanil in 50% of patients (EC50) and 95% of patients (EC95) for smooth laryngeal mask airway (LMA) removal in adults under propofol and remifentanil anesthesia. MATERIALS AND METHODS: Twenty-five patients of ASA physical status I-II and ages 18-60 years who were to undergo minor gynecological or orthopedic surgery were assessed in this study. Anesthesia was induced and maintained with propofol and remifentanil target-controlled infusion (TCI). Remifentanil was maintained at a predetermined Ce during the emergence period. The modified Dixon's up-and-down method was used to determine the remifentanil concentration, starting from 1.0 ng/mL (step size of 0.2 ng/mL). Successful removal of the LMA was regarded as absence of coughing/gagging, clenched teeth, gross purposeful movements, breath holding, laryngospasm, or desaturation to SpO2<90%. RESULTS: The mean±SD Ce of remifentanil for smooth LMA removal after propofol anesthesia was 0.83±0.16 ng/mL. Using isotonic regression with a bootstrapping approach, the estimated EC50 and EC95 of remifentanil Ce were 0.91 ng/mL [95% confidence interval (CI), 0.77-1.07 ng/mL] and 1.35 ng/mL (95% CI, 1.16-1.38 ng/mL), respectively. CONCLUSION: Our results showed that remifentanil TCI at an established Ce is a reliable technique for achieving safe and smooth emergence without coughing, laryngospasm, or other airway reflexes.

Tongue bite in a patient with tracheostomy after prone position -A case report-.

A 22-year-old man underwent an operation for posterolateral fusion of the lumbar spine at L3-5. He was ventilated via a tracheostomy site in a prone position for 210 minutes. Ventilator function and eyeballs were checked periodically. After changing his position to supine for the wake-up test, it was noticed that his tongue was self-inflicted and looked to be cut unless immediate decompression was applied. After several manual attempts to open the mouth failed, anesthesia depth was deepened with thiopental sodium and neuromuscular blocker to decompress and reposition the tongue into the intraoral cavity. Minimal teeth marks and scarring remained after seven months without any complications.

Effect of calcium sulfate pellets on early bone mineralization in distraction osteogenesis for craniofacial microsomia in adults.

The purpose of this project was to study the effect of calcium sulfate pellets on early bony consolidation in distraction osteogenesis. A total of 13 patients (control group: five patients; calcium sulfate group: eight patients) were operated on between April 2001 and December 2004. The age of the patients ranged from 18 to 25 years. In the calcium sulfate group, after completing a mandibular osteotomy, a total of 4 mm was distracted initially. Nine to 10 calcium sulfate (Osteoset) pellets were implanted into the 4-mm distracted gap of mandible. In the control group, a mandibular osteotomy alone was created without the initial 4-mm distraction gap and the implantation of calcium sulfate. Five days after the operation, the distraction of the mandible was performed at a rate of 1 mm per day. The distracted length of the mandible was between 7 and 23 mm. The follow-up period ranged between 10 and 22 months. In the calcium sulfate group, the percentage of bone mineral density in the distracted area, compared with the normal mandible, was much higher than in the control group with a statistical significance of P < 0.05. The external distraction devices of the calcium sulfate group were removed 5 to 7 weeks after distraction. The devices of the control group were removed by 11 or 12 weeks. In conclusion, results of the present study suggested that calcium sulfate is a very active, economic, and biocompatible osteoconductive material, which has a good effect on early consolidation in distraction osteogenesis.

Anthropometric study of the upper lip and the nose of infants less than a year of age.

We divided healthy newborns (aged between 2 weeks and 6 months) into four groups, less than 2 weeks old, 60 +/- 7 days, 120 +/- 7 days, and 180 +/- 7 days, between June 2001 and February 2002, and each group had 40 infants. The lineal distances included 13 items related to the nose, mouth, and lips. The average width of the columella at the midpoint was 3.2, 3.5, 3.7, and 3.8 mm for the 2-week-old group, the 2-month-old group, the 4-month-old group, and the 6-month-old group, respectively. The average height of the columella was 4.7, 4.9, 5.2, and 5.3 mm. The average length between the medial alar bases was 13.7, 14.4, 17.4, and 17.6 mm. The average length from the base to the tip of Cupid's bow was 9.5, 10.0, 10.5, and 10.6 mm. The average length from the columella lateral base to the tip of Cupid's bow was 8.4, 9.9, 10.2, and 10.5 mm. The average length from the columella central base to the center of Cupid's bow was 8.3, 9.5, 9.8, and 9.9 mm. The average width of one limb of Cupid's bow was 2.7, 3.1, 3.4, and 3.5 mm. The average length from the tip of Cupid's bow to the commissure was 13.4, 14.7, 16.4, and 16.9 mm. The average intercommissural distance was 26.8, 30.3, 30.8, and 32.7 mm. The average width of the philtral column at the columella base was 3.1, 3.6, 3.7, and 4.0 mm. The average width of the philtral columns at the mid-portion was 3.7, 4.6, 4.6, and 4.6 mm. The average height of the nasal tip protrusion was 8.7, 11.0, 11.7, and 12.1 mm. The average width of the nose was 20.7, 23.7, 25.3, and 25.9 mm. In conclusion, these data are expected to be useful for patients with a bilateral cleft lip.

Influence of the Furlow palatoplasty for patients with submucous cleft palate on facial growth.

The purpose of this study was to investigate the facial growth in patients with submucous cleft palate operated on using the Furlow palatoplasty. A total of 30 patients with submucous cleft palate underwent Furlow palatoplasty from 1993 to 1998. The mean follow-up period was 4 years and 3 months. Twenty-five of 30 patients were followed up. Mid-facial growth was measured using lateral cephalograms in 18 patients whose age was greater than 8 years. The parameters obtained in the lateral cephalogram were compared with those of a healthy population in Korea. Eleven (61.1%) of 18 patients observed were within the clinical normal range for the age group for the parameter of the span between the anterior nasal spine and posterior nasal spine, 6 patients (33.3%) were over the range, and 1 patient (5.6%) was below the range. For the sella-nasion-subspinale angle, 55.6% of patients were within the clinical normal range, 27.8% were over the range, and 16.6% were below the range. For the sella-nasion-supramentale angle, 55.6% of patients were within the clinical normal range, 22.2% were over the range, and 22.2% were below the range. For the sella-nasion-subspinale-sella-nasion-supramentale angle, 72.2% of patients were within the clinical normal range, 27.8% were over the range, and none were below the range. For the span between the basion and posterior nasal spine, 50.0% of patients were within the clinical normal range, 27.8% were over the range, and 22.2% were below the range. In conclusion, our results suggest that the Furlow palatoplasty is a useful procedure as an initial treatment of submucous cleft palate and that this technique has a less harmful effect on facial growth because there is no excessive surgical intervention on the hard palate and alveolar process.

The bone regenerative effect of chitosan microsphere-encapsulated growth hormone on bony consolidation in mandibular distraction osteogenesis in a dog model.

The purpose of this project was to study the effect of chitosan microsphere-encapsulated human growth hormone, which causes sustained release of chitosan and human growth hormone after implantation on early bony consolidation in distraction osteogenesis of a canine model. Forty-eight dogs were used for this study. An external distraction device was applied to the mandibular body after a vertical osteotomy, and the mandibular distraction was started 5 days after the operation at a rate of 1 mm/d up to a 10-mm distraction. The experimental group was divided into a control group (I), hyaluronic acid group (II), chitosan microsphere group (III), and chitosan microsphere-encapsulated human growth hormone group (IV). Normal saline was injected in group I. In group II, a 1-ml volume of hyaluronic acid solution was injected into the distracted area. In the group III, powder of chitosan microspheres and hGH were mixed with a 1-ml volume of hyaluronic acid to make an injectable form, and it was implanted into the distracted area. In group IV, powder of chitosan microsphere-encapsulated hGH was mixed with a 1-ml volume of hyaluronic acid. A total of 1-ml volume of the solution mix was implanted into the distracted area. Five dogs in each group (total of 20 dogs) were killed 3 weeks after completion of distraction. Twenty-eight dogs were killed at 6 weeks. Bone mineral density was 13.1% of the contralateral normal mandible at 3 weeks and 29.6% at 6 weeks in group I, 16.4% at 3 weeks and 40.4% at 6 weeks in group II, 16.6% at 3 weeks and 45.95% at 6 weeks in group III, and 29.6% at 3 weeks and 66.7% at 6 weeks in group IV. The mean three-point failure load was 16.1% in the control group, 34.7% in group II, 41.5% in group III, and 52.1% in group IV compared with the intact contralateral mandible, with statistical significance. In the histological findings, new bone was generated in all groups. In group IV, the formation of active woven bone was observed throughout the distracted area at 6 weeks. The amount of new bone formation in the distracted zone was in the order of group IV, group III, group II, and the control group. In conclusion, these findings suggest that chitosan microsphere-encapsulated hGH seems to be quite effective in early bone consolidation in distraction osteogenesis.