Managing a difficult airway due to supraglottic masses: successful videolaryngoscopic intubation after induction of general anesthesia.

BACKGROUND: While awake, flexible bronchoscopic intubation has long been considered the gold standard for managing anticipated difficult airways, the videolaryngoscope has emerged as a viable alternative. In addition, the decision to perform awake intubation or to proceed with airway management after induction of general anesthesia should be grounded in a comprehensive assessment of risks and benefits. CASE PRESENTATION: A 41-year old female patient was scheduled for excision of bilateral, mobile, and pedunculated masses on both aryepiglottic folds, which covered almost the entire upper part of the glottis. We conducted a comprehensive evaluation of the patient's signs and symptoms, which included neither stridor nor dyspnea in any position, along with the otolaryngologist's opinion and the findings from the laryngeal fiberscopic examination. Given the potential challenges and risks associated with awake flexible bronchoscopic intubation for this patient, we decided to proceed with gentle tracheal intubation using a videolaryngoscope under general anesthesia. In case of failed mask ventilation and tracheal intubation, we had preplanned strategies, including awakening the patient or performing an emergent tracheostomy, along with preparations to support these strategies. Ensuring that mask ventilation was maintained with ease, the patient was sequentially administered intravenous propofol, remifentanil, and rocuronium. Under sufficient depth of anesthesia, intubation using a videolaryngoscope was successfully performed without any complications. CONCLUSIONS: Videolaryngoscopic intubation after induction of general anesthesia can be a feasible alternative for managing difficult airways in patients with supraglottic masses. This approachshould be based on a comprehensive preoperative evaluation, adequate preparation, and preplanned strategies to address potential challenges, such as inadequate oxygenation and unsuccessful tracheal intubation.

Single-Stage Peninsular-Shaped Lateral Tongue Flap for Personalized Reconstruction of Various Small- to Moderate-Sized Intraoral Defects: A Retrospective Case Series with Tongue Function Evaluation Using the Functional Intraoral Glasgow Scale.

Herein, we present our experience using a single-stage peninsular-shaped lateral tongue flap (pLTF) to cover various intraoral defects and confirm the versatile utility and effective application of pLTF in intraoral defect reconstruction. This study included eight cases (six males and two females; average age 60.3 ± 16.9 years) of intraoral defect reconstruction performed by a single surgeon between August 2020 and May 2023 using the single-stage pLTF technique. Electronic medical records and photographs of the patients were collected and analyzed. The functional intraoral Glasgow scale (FIGS) was used to evaluate preoperative and postoperative tongue function. Defect sizes ranged from 3 cm × 3 cm to 4 cm × 6 cm. Notably, all defects were successfully covered with pLTFs, and the flap sizes ranged between 3 cm × 4.5 cm and 4.5 cm × 7.5 cm. The flaps completely survived without any postoperative complications. At follow-up (average, 9.87 ± 2.74 months), no patient had tumor recurrence or significant tongue functional deficits. The mean preoperative and postoperative FIGS were 14.75 ± 0.46 and 14.00 ± 0.92, respectively (p = 0.059). Thus, the single-stage pLTF technique is a good reconstructive modality for various small to moderate intraoral defect coverage in selected cases for personalized intraoral reconstruction.

Comparison of the Nasal Cavity Guidance Methods' Effects during Nasotracheal Intubation Using a Preformed Nasotracheal Tube: A Prospective Randomized Controlled Trial.

Nasotracheal intubation is mainly performed to provide a safe airway during maxillofacial surgeries. Several guiding devices are suggested to facilitate nasotracheal intubation and reduce complications. We attempted to compare intubation conditions during nasotracheal intubation using a nasogastric tube and a suction catheter, which are readily available in operating rooms. In this study, 114 patients undergoing maxillofacial surgery were randomly divided into the nasogastric tube guidance group (NG group) and the suction catheter guidance group (SC group). The primary outcome was the total intubation time. Moreover, the incidence and degree of epistaxis, the position of the tube in the nasal cavity after intubation, and the number of manipulations during intubation in the nasal cavity were investigated. The insertion time from the nostril to the oral cavity and the total intubation time were significantly shorter in the SC group than in the NG group (p < 0.001). The incidence of epistaxis was lower at 35.1% in the NG group and 43.9% in the SC group than the previously reported 60-80%, but there was no statistical difference between the two groups. The use of a suction catheter aid during nasotracheal intubation can be used effectively because it shortens the intubation time and does not increase complications.

Ramped versus sniffing position in the videolaryngoscopy-guided tracheal intubation of morbidly obese patients: a prospective randomized study.

BACKGROUND: Ramped positioning is recommended for intubating obese patients undergoing direct laryngoscopy. However, whether the use of the ramped position can provide any benefit in videolaryngoscopy-guided intubation remains unclear. This study assessed intubation time using videolaryngoscopy in morbidly obese patients in the ramped versus sniffing positions. METHODS: This is a prospective randomized study in patients with morbid obesity (n = 82; body mass index [BMI] ≥ 35 kg/m2). Patients were randomly allocated to either the ramped or the standard sniffing position groups. During the induction of general anesthesia, difficulty in mask ventilation was assessed using the Warters scale. Tracheal intubation was performed using a C-MAC® D-Blade videolaryngoscope, and intubation difficulty was assessed using the intubation difficulty scale (IDS). The primary endpoint was the total intubation time calculated as the sum of the laryngoscopy and tube insertion times. RESULTS: The percentage of difficult mask ventilation (Warters scale ≥ 4) was significantly lower in the ramped (n = 40) than in the sniffing group (n = 41) (2.5% vs. 34.1%, P < 0.001). The percentage of easy intubation (IDS = 0) was significantly higher in the ramped than in the sniffing group (70.0% vs. 7.3%, P < 0.001). The total intubation time was significantly shorter in the ramped than in the sniffing group (22.5 ± 6.2 vs. 40.9 ± 9.0, P < 0.001). CONCLUSIONS: Compared with the sniffing position, the ramped position reduced intubation time in morbidly obese patients and effectively facilitated both mask ventilation and tracheal intubation using videolaryngoscopy.

Head-neck movement may predispose to the development of arytenoid dislocation in the intubated patient: a 5-year retrospective single-center study.

BACKGROUND: Arytenoid dislocation is a rare laryngeal injury that may follow endotracheal intubation. We aimed to determine the incidence and risk factors for arytenoid dislocation after surgery under general anaesthesia. METHODS: We reviewed the medical records of patients who underwent operation under general anaesthesia with endotracheal intubation from January 2014 to December 2018. Patients were divided into the non-dislocation and dislocation groups depending on the presence or absence of arytenoid dislocation. Patient, anaesthetic, and surgical factors associated with arytenoid dislocation were determined using Poisson regression analysis. RESULTS: Among the 25,538 patients enrolled, 33 (0.13%) had arytenoid dislocation, with higher incidence after anterior neck and brain surgery. Patients in the dislocation group were younger (52.6 ± 14.4 vs 58.2 ± 14.2 yrs, P = 0.025), more likely to be female (78.8 vs 56.5%, P = 0.014), and more likely to be intubated by a first-year anaesthesia resident (33.3 vs 18.5%, P = 0.048) compared to those in the non-dislocation group. Patient positions during surgery were significantly different between the groups (P = 0.000). Multivariable Poisson regression identified head-neck positioning (incidence rate ratio [IRR], 3.10; 95% confidence interval [CI], 1.50-6.25, P = 0.002), endotracheal intubation by a first-year anaesthesia resident (IRR, 2.30; 95% CI, 1.07-4.64, P = 0.024), and female (IRR, 3.05; 95% CI, 1.38-7.73, P = 0.010) as risk factors for arytenoid dislocation. CONCLUSION: This study showed that the incidence of arytenoid dislocation was 0.13%, and that head-neck positioning during surgery, less anaesthetist experience, and female were significantly associated with arytenoid dislocation in patients who underwent surgeries under general anaesthesia with endotracheal intubation.

Comparisons of surgical conditions of deep and moderate neuromuscular blockade through multiple assessments and the quality of postoperative recovery in upper abdominal laparoscopic surgery.

STUDY OBJECTIVE: To determine the effect of deep neuromuscular blockade (NMB) on surgical field conditions through multiple assessments during pneumoperitoneum and evaluate the effect of the depth of intraoperative NMB on the quality of postoperative recovery over multiple time periods. DESIGN: Prospective randomized study. SETTING: Operating room of a university hospital. PATIENTS: Eighty non-morbidly obese patients (ASA physical status 1-2) who were scheduled to undergo laparoscopic gastrectomy in the reverse Trendelenburg position. INTERVENTIONS: Patients were allocated to either the deep or moderate NMB group. The depth of NMB was maintained at a post-tetanic count of 1 for deep NMB with a continuous infusion of rocuronium and at a train-of-four count of 1 for moderate NMB with a small intermittent bolus of cisatracurium. MEASUREMENTS: Single-blinded scoring of the quality of the surgical field condition was performed by a surgeon using a five-point scale in a 15-min interval during pneumoperitoneum. The quality of postoperative recovery was assessed using the Postoperative Quality of Recovery Scale (PostopQRS) on the day before surgery (baseline) and 1 h, 1 day, and 6 days after surgery. MAIN RESULTS: Optimal surgical field condition was rated in 87.0% (449/516) and 72.3% (370/512) of all measurements during deep and moderate NMB, respectively (P < 0.001). The percentage of patients maintaining a good-to-optimal condition throughout pneumoperitoneum was higher in the deep NMB group than in the moderate NMB group. There were no significant differences in the percentage of recovered patients between the two groups for all domains and all timepoints. CONCLUSIONS: Multiple assessments of the surgical field condition demonstrated that deep NMB provided a more satisfactory surgical field condition than moderate NMB during laparoscopic gastrectomy. However, the quality of postoperative recovery, assessed using the PostopQRS, was not different between the two groups according to the depth of NMB.

Resveratrol suppresses the reprogramming of macrophages into an endotoxin-tolerant state through the activation of AMP-activated protein kinase.

Resveratrol has been reported to have beneficial effects on sepsis by regulating the inflammatory response. However, it remains unclear if resveratrol plays a role in the development of endotoxin tolerance. Treatment with resveratrol in macrophages stimulated with primary lipopolysaccharide (LPS) resulted in the increased production of TNF-α and IL-6 induced by a 2nd dose of LPS (by 74.5 ± 12.9% and 63.4 ± 12%, respectively, compared to untreated cells, P < 0.05). This effect was inhibited by compound C, an AMPK inhibitor, and STO609, a calcium/calmodulin-dependent protein kinase-kinase (CaMKK) inhibitor. Resveratrol diminished the expression of interleukin-1 receptor-associated kinase M (IRAK-M) and Src homology 2 (SH2) domain-containing inositol-5-phosphatase 1 (SHIP1) by prolonging the exposure of cells to LPS (by 60.8 ± 16.3% and 70.3 ± 18.1%, respectively, compared to LPS only). The effect of resveratrol on the LPS-induced expression of IRAK-M and SHIP1 was inhibited by compound C or STO609. After a 2nd dose of LPS, resveratrol increased phosphorylation of ERK1/2, p38, and JNK in endotoxin tolerant macrophages. In vivo systemic administration of resveratrol prevented a significant increase in mortality rate by cecal ligation and puncture in LPS-induced endotoxin-tolerant mice. These results indicate that resveratrol induces AMPK activation through the Ca2+/CaMKKß pathway and suppresses the development of endotoxin tolerance by inhibiting LPS-induced expression of IRAK-M and SHIP1.

Donepezil-related inadequate neuromuscular blockade during laparoscopic surgery: A case report.

BACKGROUND: Donepezil is an acetylcholinesterase inhibitor used to improve cognition and delay disease progression in dementia patients by increasing acetylcholine levels. This drug may potentially interact with neuromuscular blocking agents (NMBAs) that act on muscular acetylcholine receptors during general anesthesia. Herein, we present a case of inadequate neuromuscular blockade with rocuronium, a nondepolarizing NMBA, in a dementia patient who had taken donepezil. CASE SUMMARY: A 71-year-old man was scheduled for laparoscopic gastrectomy. He had been taking donepezil 5 mg for dementia. General anesthesia was induced with propofol and remifentanil. The depth of neuromuscular blockade was monitored by train-of-four (TOF) stimulation. After the administration of rocuronium, the TOF ratio decreased at an unusually slow rate, and a TOF count of 0 was detected 7 min later. After intubation, a TOF count of 1 was detected within 1 min, and a TOF ratio of 12% was detected within 2 min. The TOF count remained at 4 even with an additional bolus and continuous infusion of rocuronium, suggesting resistance to this NMBA. Instead of propofol, an inhalation anesthetic was administered alongside another NMBA (cisatracurium). Then, the quality of neuromuscular blockade improved, and the TOF count remained at 0-1 for the next 70 min. No further problems were encountered with respect to surgery or anesthesia. CONCLUSION: Donepezil may be responsible for inadequate neuromuscular blockade during anesthesia, especially when total intravenous anesthesia is used.

Causal mediation analysis in nested case-control studies using conditional logistic regression.

The paper proposes an approach to causal mediation analysis in nested case-control study designs, often incorporated with countermatching schemes using conditional likelihood, and we compare the method's performance to that of mediation analysis using the Cox model for the full cohort with a continuous or dichotomous mediator. Simulation studies are conducted to assess our proposed method and investigate the efficiency relative to the cohort. We illustrate the method using actual data from two studies of potential mediation of radiation risk conducted within the Adult Health Study cohort of atomic-bomb survivors. The performance becomes comparable to that based on the full cohort, illustrating the potential for valid mediation analysis based on the reduced data obtained through the nested case-control design.

The effects of BMS-470539 on lipopolysaccharide-induced acute lung injury.

BACKGROUND: Overactivation of inflammatory cells, including macrophages and neutrophils, is associated with acute lung injury. BMS-470539 is a selective agonist of melanocortin 1 receptor, which triggers the inhibition of proinflammatory responses, suppressing neutrophil infiltration and protecting tissue. This study evaluated the effects of BMS-470539 on lipopolysaccharide-induced acute lung injury in a mouse model. METHODS: Mice received a subcutaneous injection of saline or BMS-470539 (18.47 mg/kg) 1 hour before an intratracheal injection of saline or lipopolysaccharide (20 µg). Mice were sacrificed to analyze the severity of pulmonary edema (lung wet-to-dry weight [W/D] ratio) and inflammatory responses (level of leukocytes, polymorphonuclear neutrophils [PMNs] and tumor necrosis factor alpha [TNF-α] in bronchoalveolar lavage fluid [BALF]), and neutrophil infiltration (myeloperoxidase activity). TNF-α activation was also measured in neutrophils from bone marrow. Survival was investigated in a second-hit sepsis mouse model. RESULTS: BMS-470539 improved sepsis-induced pulmonary edema, as demonstrated by a decreased W/D ratio (5.76%±0.83% to 3.81%±0.86%, P<0.05). The inflammatory response also improved, as shown by decreased levels of leukocytes (551±116 to 357±86×10²/mm³, P<0.05), PMNs (51.52%±16.23% to 18.41%±7.25%, P<0.01), and TNF-α (550±338 to 128±52 pg/ml, P<0.01) in the BALF. BMS-470539 also improved the inflammatory response, as shown by TNF-α levels (850±158 to 423±59 pg/ml, P<0.01) in neutrophils. BMS-470539 downregulated neutrophil infiltration in the lung (myeloperoxidase: 654±98 to 218±89 U/g, P<0.001). Lastly, BMS improved the survival rate (0% to 70%, P<0.01) in a mice multiple organ failure model. CONCLUSIONS: BMS-470539 improved lipopolysaccharide-induced acute lung injury and mortality in mice by affecting the inflammatory response.

Ginsenoside Rg3 promotes Fc gamma receptor-mediated phagocytosis of bacteria by macrophages via an extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase-dependent mechanism.

Ginsenoside Rg3 is a steroidal saponin abundant in Korean red ginseng that has high anti-inflammatory activity. Rg3 exerts an immunomodulatory effect in acute inflammatory conditions such as bacterial infections. In this study, we determined the effect of Rg3 on bacterial uptake by macrophages and the related intracellular signaling pathways. Rg3 increased macrophage phagocytosis of IgG-opsonized Escherichia coli and IgG-opsonized beads (IgGbeads), but not of non-opsonized beads. Rg3 also enhanced the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 and p38 mitogen-activated protein kinase (p38 MAPK), but not that of Akt. The inclusion of IgGbeads in macrophage cultures also increased the phosphorylation of ERK1/2 and p38, but co-culture of macrophages with non-opsonized beads did not affect the phosphorylation of ERK1/2 and p38. The Rg3-induced promotion of phagocytosis was inhibited by PD98059, an ERK1/2 inhibitor, and SB203580, a p38 inhibitor. PD98059 inhibited Rg3-induced p38 MAPK phosphorylation, but SB203580 did not suppress ERK1/2 phosphorylation. Culture of macrophages with Rg3 increased actin polymerization, and this effect was inhibited by SB203580 and PD98059. The Rg3-induced increase in phagocytosis was also inhibited by NSC23766, a Rac1 inhibitor and CASIN, a Cdc42 inhibitor. Intraperitoneal injection of Rg3 increased the phosphorylation of ERK1/2 and p38 as well as the phagocytosis of bacteria by lung cells. These results demonstrate that ginsenoside Rg3 enhances macrophage phagocytosis of bacteria by activating the ERK1/2 and p38 MAPK pathways.

Stearoyl lysophosphatidylcholine inhibits LPS-induced extracellular release of HMGB1 through the G2A/calcium/CaMKKß/AMPK pathway.

Stearoyl lysophosphatidylcholine (sLPC) has protective effects against several lethal sepsis models, even after induction of sepsis, which is associated with sLPC-mediated inhibition of high mobility group box 1 (HMGB1) release. This study investigated the mechanism by which sLPC inhibits lipopolysaccharide (LPS)-induced extracellular secretion of HMGB1 after the onset of sepsis. sLPC increased AMPK phosphorylation and the binding of AMPK to calcium/calmodulin-dependent protein kinase kinase ß (CaMKKß), one of the upstream signals of AMPK. Inhibition of CaMKKß activity decreased sLPC-mediated inhibition of HMGB1 release, and sLPC increased the concentration of intracellular calcium. Blocking of the macrophage G protein-coupled receptor G2A (G2A) suppressed AMPK phosphorylation, suppressed increases in the intracellular levels of calcium, and prevented the inhibition of HMGB1 release by sLPC. In particular, when macrophages were incubated with sLPC even after LPS treatment, sLPC increased the phosphorylation of AMPK and the binding of CaMKKß and AMPK, and suppressed the secretion of HMGB1. In addition, sLPC administered 1 h before or 4 h after establishment of sepsis significantly diminished circulating HMGB1 levels in mice. sLPC inhibited LPS-induced extracellular release of HMGB1 through the activation of the G2A/calcium/CaMKKß/AMPK pathway. These findings suggest that sLPC may be a potential anti-inflammatory agent for acute inflammatory conditions such as sepsis.

Comparison of vocal cord view between neutral and sniffing position during orotracheal intubation using fiberoptic bronchoscope: a prospective, randomized cross over study.

BACKGROUND: In intubation using fiberoptic bronchoscope (FOB), partial or complete obstruction of upper airway makes the FOB insertion difficult. Thus, maneuvers to relieve such obstructions are recommended. There have been no studies to determine whether the sniffing or neutral position is superior for this purpose. Therefore, this study was performed to examine the effects of these two positions including vocal cord view. METHODS: Fifty-four patients scheduled to receive general anesthesia by orotracheal intubation were eligible for inclusion in the study with informed consent. After confirmation of proper head positioning depending on the group, the view of the vocal cord was acquired in each position. Images were reviewed using the percentage of glottic opening (POGO) score. RESULTS: A total of 106 images of vocal cords from 53 patients were obtained. The mean of difference of POGO score was 11.09, higher for the neutral position and standard deviation was 23.73 (p = 0.002). Neutral position increased POGO score in 31 patients and decreased POGO score in 13 patients compare to sniffing position (p = 0.017). There were no significant differences between the two head positions with regard to intubation time or degree of convenience during intubation. CONCLUSIONS: Neutral position improved the view of glottic opening than sniffing position during oral fiberoptic intubation. However, there was no difference in the difficulty of tube insertion between the two positions. TRIAL REGISTRATION: Clinical Trials.gov identifier: NCT02931019 , registered on October 12, 2016.

L2-L1 Translation Priming Effects in a Lexical Decision Task: Evidence From Low Proficient Korean-English Bilinguals.

One of the key issues in bilingual lexical representation is whether L1 processing is facilitated by L2 words. In this study, we conducted two experiments using the masked priming paradigm to examine how L2-L1 translation priming effects emerge when unbalanced, low proficiency, Korean-English bilinguals performed a lexical decision task. In Experiment 1, we used a 150 ms SOA (50 ms prime duration followed by a blank interval of 100 ms) and found a significant L2-L1 translation priming effect. In contrast, in Experiment 2, we used a 60 ms SOA (50 ms prime duration followed by a blank interval of 10 ms) and found a null effect of L2-L1 translation priming. This finding is the first demonstration of a significant L2-L1 translation priming effect with unbalanced Korean-English bilinguals. Implications of this work are discussed with regard to bilingual word recognition models.

Background anaesthetic agents do not influence the impact of arginine vasopressin on haemodynamic states and cerebral oxygenation during shoulder surgery in the beach chair position: a prospective, single-blind study.

BACKGROUND: Administration of arginine vasopressin (AVP) is associated with reducing jugular venous (SjvO2) and regional cerebral (rScO2) oxygen saturation under propofol-remifentanil (P/R) anaesthesia. We determined whether background anaesthetics modulate the effect of AVP on cerebral oxygenation and haemodynamics. METHODS: We randomly allocated 60 adult patients scheduled for shoulder surgery in the beach chair position (BCP) into 4 groups, to receive either an intravenous bolus of saline (groups PR-S and SN-S) or 0.05 U/kg AVP (groups PR-AVP and SN-AVP) under P/R or sevoflurane-nitrous oxide (S/N) anaesthesia (n = 15 each). Haemodynamic variables, SjvO2 and rScO2 were measured. RESULTS: AVP significantly increased mean arterial blood pressure (MAP) and decreased rScO2 in either anaesthetic group. AVP also decreased SjvO2 in the P/R groups but not in the S/N groups. The AVP-treated groups showed higher MAP and cerebral desaturation (>20% rScO2 decrease from baseline), along with lower HR and rScO2 in the BCP than those in the saline-treated groups. In contrast, AVP did not affect SjvO2 values or the incidence of SjvO 2  < 50%. Baseline SjvO2 was lower and the magnitude of its reduction in the BCP was greater in the PR-AVP group than in the SN-AVP group, and the lowest SjvO2 values were 37 ± 6 and 57 ± 8%, respectively (P < 0.001). CONCLUSIONS: The choice of anaesthetic regimen did not affect cerebral oxygenation or haemodynamics of AVP in the BCP. However, the negative effect of AVP on cerebral oxygenation should be considered, especially under P/R anaesthesia. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01687894 , registered on September 18, 2012.