Revealing the Filler-Matrix Interfacial Interactions: Real-Time Observation with Mechano-Responsive Spiropyran Microbeads.

Interfacial interactions between polymers and fillers play a crucial role in determining the performance of composite materials. In this study, mechano-responsive spiropyran (SP) beads, which exhibit fluorescence changes under stress, serve as force probes to evaluate force transfer efficiency across two types of interfaces: noncovalent and covalent. These interfaces are engineered by respectively employing physical blending and grafting polymerization to integrate hydroxyl SP beads with a polyurethane (PU) matrix. A custom-built in situ opto-mechanical setup quantitatively assesses force transfer by monitoring changes in fluorescence intensity and peak wavelength during specimen stretching. The analysis reveals that the covalent interface significantly outperforms the noncovalent interface, demonstrating a 100% improvement in force magnitude and transfer rate from the PU matrix to the SP beads. Direct observation of SP beads within the PU matrix during tension unveils that enhanced force transfer efficiency is closely linked to changes in the SP beads' aspect ratio. Fluorescence changes in SP beads are solely a function of aspect ratio, making them effective independent force probes.

Multifunctional MXene/Carbon Nanotube Janus Film for Electromagnetic Shielding and Infrared Shielding/Detection in Harsh Environments.

Multifunctional, flexible, and robust thin films capable of operating in demanding harsh temperature environments are crucial for various cutting-edge applications. This study presents a multifunctional Janus film integrating highly-crystalline Ti3C2Tx MXene and mechanically-robust carbon nanotube (CNT) film through strong hydrogen bonding. The hybrid film not only exhibits high electrical conductivity (4250 S cm-1), but also demonstrates robust mechanical strength and durability in both extremely low and high temperature environments, showing exceptional resistance to thermal shock. This hybrid Janus film of 15 µm thickness reveals remarkable multifunctionality, including efficient electromagnetic shielding effectiveness of 72 dB in X band frequency range, excellent infrared (IR) shielding capability with an average emissivity of 0.09 (a minimal value of 0.02), superior thermal camouflage performance over a wide temperature range (- 1 to 300 °C) achieving a notable reduction in the radiated temperature by 243 °C against a background temperature of 300 °C, and outstanding IR detection capability characterized by a 44% increase in resistance when exposed to 250 W IR radiation. This multifunctional MXene/CNT Janus film offers a feasible solution for electromagnetic shielding and IR shielding/detection under challenging conditions.

Video-based automatic hand hygiene detection for operating rooms using 3D convolutional neural networks.

Hand hygiene among anesthesia personnel is important to prevent hospital-acquired infections in operating rooms; however, an efficient monitoring system remains elusive. In this study, we leverage a deep learning approach based on operating room videos to detect alcohol-based hand hygiene actions of anesthesia providers. Videos were collected over a period of four months from November, 2018 to February, 2019, at a single operating room. Additional data was simulated and added to it. The proposed algorithm utilized a two-dimensional (2D) and three-dimensional (3D) convolutional neural networks (CNNs), sequentially. First, multi-person of the anesthesia personnel appearing in the target OR video were detected per image frame using the pre-trained 2D CNNs. Following this, each image frame detection of multi-person was linked and transmitted to a 3D CNNs to classify hand hygiene action. Optical flow was calculated and utilized as an additional input modality. Accuracy, sensitivity and specificity were evaluated hand hygiene detection. Evaluations of the binary classification of hand-hygiene actions revealed an accuracy of 0.88, a sensitivity of 0.78, a specificity of 0.93, and an area under the operating curve (AUC) of 0.91. A 3D CNN-based algorithm was developed for the detection of hand hygiene action. The deep learning approach has the potential to be applied in practical clinical scenarios providing continuous surveillance in a cost-effective way.

Comparison of preoxygenation with a high-flow nasal cannula and a simple face mask before intubation in Korean patients with head and neck cancer.

BACKGROUND: Although preoxygenation is an essential procedure for safe endotracheal intubation, in some cases securing sufficient time for tracheal intubation may not be possible. Patients with head and neck cancer might have a difficult airway and need a longer time for endotracheal intubation. We hypothesized that the extended apneic period with preoxygenation via a high-flow nasal cannula (HFNC) is beneficial to patients who undergo head and neck surgery compared with preoxygenation with a simple mask. METHODS: The study was conducted as a single-center, single-blinded, prospective, randomized controlled trial. Patients were divided into groups based on one of the two preoxygenation. METHODS: HFNC group or simple facemask (mask group). Preoxygenation was performed for 5 minutes with each method, and endotracheal intubation for all patients was performed using a video laryngoscope. Oxygen partial pressures of the arterial blood were compared at the predefined time points. RESULTS: For the primary outcome, the mean arterial oxygen partial pressure (PaO2 ) immediately after intubation was 454.2 mm Hg (95% confidence interval [CI], 416.9-491.5 mm Hg) in the HFNC group and 370.7 mm Hg (95% CI, 333.7-407.4 mm Hg) in the mask group (P=0.002). The peak PaO2 at 5 minutes after preoxygenation was not statistically different between the groups (P=0.355). CONCLUSIONS: Preoxygenation with a HFNC extending to the apneic period before endotracheal intubation may be beneficial in patients with head and neck cancer.

Challenge for Trade-Off Relationship between the Mechanical Property and Healing Efficiency of Self-Healable Polyimide.

Polyimide is actively applied in various industrial fields because of its strong mechanical properties, owing to the interactions between the polymer chains. Fully aromatic imide structures exhibit high glass-transition temperatures due to the strong interactions between their chains, which hinder chain mobility. Therefore, preparing a material that exhibits self-healing at a low temperature of ≤100 °C and good mechanical properties is challenging. Thus, we prepared imides with four-component semiaromatic structures by adjusting the contents of 4,4'-(hexafluoroisopropylidene)diphthalic anhydride and 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic anhydride) to yield four-component self-healable colorless polyimides (f-SH-CPIs) with novel structures, flexibilities, good mechanical properties, and low healing temperatures. The flexibilities and distances between the polymer chains, as the basis of the trade-off relationship between the mechanical properties and healing efficiency, were controlled. These materials may be used as substrates in wearable devices and multilayer insulation that may protect from space dust, cosmic rays, and satellite fragments.

Smart Materials with Dual Functionality: Repeatable Damage-Detection and Self-Healing.

Polymer materials are extensively used because of their excellent performance; however, when used for a long time, they break and eventually lose their original properties. Thus, smart polymer materials that can repeatedly detect and repair damage must be urgently developed to increase their durability and lifespan. In this study, a smart material with dual functionality (damage-detection and self-healing) is developed via a facile method of incorporating spiropyran (SP) beads, which exhibit changes in color and fluorescence when damaged, into a Diels-Alder (DA)-based self-healing matrix. When polyurethane (PU) is added to the DA-based matrix, the dual functionality exhibits a strong dependence on the proportion of PU. Because the PU ratio affects two opposing factors (damaged area and load-bearing capacity), the damage-detecting ability exhibits the best performance at 40 wt % PU, where both factors are optimized. A high healing efficiency of 96% is achieved via a dynamic DA reaction. In particular, the repeatability of the dual-functionality is successfully attained through the reversibility of the SP beads and DA networks, where the detection and healing efficiencies are reduced by 15 and 23%, respectively, after 10 cycles. Furthermore, the reprocessed fractured specimens exhibit excellent recyclability.

Arrhythmia incidence and associated factors during volatile induction of general anesthesia with sevoflurane: a retrospective analysis of 950 adult patients.

BACKGROUND: Sevoflurane has been used to induce anaesthesia in adults due to its suitability for airway management and haemodynamic stability. Few studies have reported arrhythmia during volatile induction with sevoflurane in adults. Here, we investigated the incidence of arrhythmia and risk factors associated with its occurrence during sevoflurane induction of anaesthesia in adults. PATIENTS AND METHODS: We retrospectively analysed 950 adult patients who underwent elective ear nose and throat surgery with volatile induction using sevoflurane between May and December 2015. The incidence of arrhythmia and the factors associated with its development were analysed. RESULTS: Arrhythmia was observed in 164 (17.3%) of 950 adult patients. The most frequently observed arrhythmia was sinus tachycardia (heart rate > 120 bpm) (77 patients, 47.0%). The multivariable logistic analysis showed four independent risk factors: age (odds ratio [OR] = 0.984, 95% confidence interval [CI] = 0.973-0.996, p = 0.006), coronary artery disease (OR = 3.749, 95% CI = 1.574-8.927, p = 0.003), maximal concentration (8 vol%) of sevoflurane from the start of induction (OR = 2.696, 95% CI = 1.139-6.382, p = 0.024), and maintenance of 8 vol% sevoflurane concentration after eyelash reflex loss (OR = 1.577, 95% CI = 1.083-2.296, p = 0.018). The risk of hypotension was greater in patients in whom arrhythmia occurred, although blood pressure recovered to baseline after the concentration of sevoflurane was adjusted. CONCLUSIONS: We recommend that the sevoflurane concentration be gradually increased with continuous and vigilant electrocardiogram and blood pressure monitoring. The sevoflurane concentration should be adjusted after sufficient unconsciousness is reached.

A Prospective Randomized Comparison of Postoperative Pain and Complications after Thyroidectomy under Different Anesthetic Techniques: Volatile Anesthesia versus Total Intravenous Anesthesia.

While the postoperative outcome is favorable, post-thyroidectomy pain is considerable. Reducing the postoperative acute pain, therefore, is considered important. This study investigated whether the pain intensity and need for rescue analgesics during the immediate postoperative period after thyroidectomy differ according to the methods of anesthesia. Seventy-two patients undergoing total thyroidectomy under general anesthesia were examined. Patients were randomly assigned to undergo either total intravenous anesthesia with remifentanil and propofol (TIVA, n = 35) or propofol induction and maintenance with desflurane and nitrous oxide (volatile anesthesia [VA], n = 37). The mean administered dose of remifentanil was 1977.7 ± 722.5 µg in the TIVA group, which was approximately 0.268 ± 0.118 µg/min/kg during surgery. Pain scores based on a numeric rating scale (NRS) and the need for rescue analgesics were compared between groups at the postoperative anesthetic care unit (PACU). The immediate postoperative NRS values of the TIVA and VA groups were 5.7 ± 1.7 and 4.7 ± 2.3, respectively (P = 0.034). Postoperative morphine equianalgesic doses in the PACU were higher in the TIVA group than in the VA group (16.7 ± 3.8 mg vs. 14.1 ± 5.9 mg, P = 0.027). The incidence of immediate postanesthetic complications did not differ significantly between groups. In conclusion, more rescue analgesics were required in the TIVA group than in the VA group to adequately manage postoperative pain while staying in the PACU after thyroidectomy.

Patient and haemodynamic factors affecting intraoperative graft flow during coronary artery bypass grafting: an observational pilot study.

Transit-time flow measurement (TTFM) is frequently used to evaluate intraoperative quality control during coronary artery bypass grafting (CABG) and has the ability to assess graft failure intraoperatively. However, perioperative factors affecting TTFM during CABG remain poorly understood. Patients who underwent CABG at a single institution between July 2016 and May 2018 were prospectively evaluated. TTFM and blood viscosity were measured haemodynamically, while mean flow (mL/min), pulsatility index, and diastolic filling were recorded. Arterial blood gas was analysed immediately after left internal mammary artery to left descending artery anastomosis and before sternal closure. Factors associated with TTFM were assessed using multiple linear regression analysis. We evaluated 57 of the 62 patients who underwent CABG during the study period, including 49 who underwent off-pump and 8 who underwent on-pump surgeries. Blood viscosity was not significantly associated with TTFM (p > 0.05). However, TTFM was significantly associated with body mass index, systolic blood pressure, and cardiac index (p < 0.05 each). In conclusion, maintaining the SBP in the perioperative period and maintaining the CI with inotropic support or fluid resuscitation can be important in improving blood flow of graft vessels after surgery.

Comparison of preoxygenation with a high-flow nasal cannula and a simple mask before intubation during induction of general anesthesia in patients undergoing head and neck surgery: Study protocol clinical trial (SPIRIT Compliant).

BACKGROUND: To assess the arterial oxygen partial pressure (PaO2) at defined time points during preoxygenation and to compare high-flow heated humidified nasal oxygenation with standard preoxygenation using oxygen insufflation via a facemask for at least 5 minutes, before intubation during induction of general anesthesia. METHODS: This randomized, single-blinded, prospective study will be conducted in patients undergoing head and neck surgery. After standard monitoring, the artery catheter at the radial artery or dorsalis pedis artery will be placed and arterial blood gas analysis (ABGA) for baseline values will be performed simultaneously. Each group will be subjected to 1 of 2 preoxygenation methods (high-flow nasal cannula or simple facemask) for 5 minutes, and ABGA will be performed twice. After confirming intubation, we will start mechanical ventilation and check the vital signs and perform the final ABGA. DISCUSSION: This trial aims to examine the trajectory of PaO2 levels during the whole preoxygenation procedure and after intubation. We hypothesize that preoxygenation with the high-flow nasal cannula will be superior to that with the face mask. STUDY REGISTRATION: This trial was registered with the Clinical Trial Registry (NCT03896906; ClinicalTrials.gov).

Comparison of five glomerular filtration rate estimating equations as predictors of acute kidney injury after cardiovascular surgery.

We aimed to compare the ability of preoperative estimated glomerular filtration rate (eGFR), calculated using five different equations, to predict adverse renal outcomes after cardiovascular surgery. Cohorts of 4,125 adult patients undergoing elective cardiovascular surgery were evaluated. Preoperative eGFR was calculated using the Cockcroft-Gault, Modification of Diet in Renal Disease (MDRD) II, re-expressed MDRD II, Chronic Kidney Disease Epidemiology Collaboration, and Mayo quadratic (Mayo) equations. The primary outcome was postoperative acute kidney injury (AKI), defined by Kidney Disease: Improving Global Outcomes Definition and Staging criteria based on changes in serum creatinine concentrations within 7 days. The MDRD II and Cockcroft-Gault equations yielded the highest (88.1 ± 26.7 ml/min/1.73 m2) and lowest (79.6 ± 25.5 ml/min/1.73 m2) mean eGFR values, respectively. Multivariable analysis showed that a preoperative decrease in renal function according to all five equations was independently associated with an increased risk of postoperative AKI. The area under the receiver operating characteristics curve for predicting postoperative AKI was highest for the Mayo equation (0.713). Net improvements in reclassification and integrated discrimination were higher for the Mayo equation than for the other equations. The Mayo equation was the most accurate in predicting postoperative AKI in patients undergoing cardiovascular surgery.

The relationship of preoperative estimated glomerular filtration rate and outcomes after cardiovascular surgery in patients with normal serum creatinine: a retrospective cohort study.

BACKGROUND: Although serum creatinine concentration has been traditionally used as an index of renal function in clinical practice, it is considered relatively inaccurate, especially in patients with mild renal dysfunction. This study investigated the usefulness of preoperative estimated glomerular filtration rate (eGFR) in predicting complications after cardiovascular surgery in patients with normal serum creatinine concentrations. METHODS: This study included 2208 adults undergoing elective cardiovascular surgery. Preoperative eGFR was calculated using Chronic Kidney Disease Epidemiology Collaboration equations. The relationships between preoperative eGFR and 90 day postoperative composite major complications were analyzed, including 90 day all-cause mortality, major adverse cardiac and cerebrovascular events, severe acute kidney injury, respiratory and gastrointestinal complications, wound infection, sepsis, and multi-organ failure. RESULTS: Of the 2208 included patients, 185 (8.4%) had preoperative eGFR < 60 mL/min/1.73 m2 and 328 (14.9%) experienced postoperative major complications. Multivariable logistic regression analyses showed that preoperatively decreased eGFR was independently associated with an increased risk of composite 90 day major postoperative complications (adjusted odds ratio: 1.232; 95% confidence interval [CI]: 1.148-1.322; P <  0.001). eGFR was a better discriminator of composite 90 day major postoperative complications than serum creatinine, with estimated c-statistics of 0.724 (95% CI: 0.694-0.754) for eGFR and 0.712 (95% CI: 0.680-0.744) for serum creatinine (P = 0.008). CONCLUSIONS: Decreased eGFR was significantly associated with an increased risk of major complications after cardiovascular surgery in patients with preoperatively normal serum creatinine concentrations.

Perioperative rupture risk of unruptured intracranial aneurysms in cardiovascular surgery.

Although unruptured intracranial aneurysms are increasingly being diagnosed incidentally, perioperative rupture risk of unruptured intracranial aneurysm in patients undergoing cardiovascular surgery remains unclear. Therefore, we conducted an observational study to assess the prevalence and perioperative rupture risk of unruptured intracranial aneurysm in patients undergoing cardiovascular surgery. Adult patients (n = 4864) who underwent cardiovascular surgery between January 2010 and December 2016 were included. We assessed the prevalence of unruptured intracranial aneurysms in these patients using preoperative neurovascular imaging. The incidence of postoperative 30-day subarachnoid haemorrhage from aneurysmal rupture was investigated in patients undergoing cardiovascular surgery with unruptured intracranial aneurysm. Postoperative outcomes were compared between patients with unruptured intracranial aneurysm and those without unruptured intracranial aneurysm. Of the 4864 patients (39.6% females; mean ± standard deviation age, 62.3 ± 11.3 years), 353 patients had unruptured intracranial aneurysms (prevalence rate, 7.26%; 95% confidence interval, 6.52-8.06%). Of these, eight patients received surgical or endovascular treatment before surgery and 345 patients underwent cardiovascular surgery with unruptured intracranial aneurysms. Within 30 days postoperatively, subarachnoid haemorrhage occurred only in one patient, and the cumulative postoperative 30-day subarachnoid haemorrhage incidence was 0.29% (95% confidence interval, 0.01% to 1.61%). The Kaplan-Meier estimated subarachnoid haemorrhage probabilities according to the unruptured intracranial aneurysm rupture risk scores were not higher than the previously reported risk in the general population. There were no significant differences in postoperative subarachnoid haemorrhage-free survival, haemorrhagic stroke-free survival, in-hospital mortality, and hospital length of stay between patients with unruptured intracranial aneurysm and those without unruptured intracranial aneurysm. In conclusion, the prevalence of unruptured intracranial aneurysm in patients undergoing cardiovascular surgery is higher than in the general population. However, incidentally detected unruptured intracranial aneurysms are not linked to an increased risk of subarachnoid haemorrhage or adverse postoperative outcomes. These findings may help determine the optimal management of unruptured intracranial aneurysms before cardiovascular surgery.

Effect of restrictive fluid therapy with hydroxyethyl starch during esophagectomy on postoperative outcomes: a retrospective cohort study.

BACKGROUND: To improve prognosis after esophageal surgery, intraoperative fluid optimization is important. Herein, we hypothesized that hydroxyethyl starch administration during esophagectomy reduce the total amount of fluid infused and it could have a positive effect on postoperative complication occurrence and mortality. METHODS: All consecutive adult patients who underwent elective esophageal surgery for cancer were studied. The primary outcome was the development of composite complications including death, cardio-cerebrovascular complications, respiratory complications, renal complications, gastrointestinal complications, sepsis, empyema or abscess, and multi-organ failure. The relationship between perioperative variables and composite complication was evaluated using multivariable logistic regression. RESULTS: Of 892 patients analyzed, composite complications developed in 271 (30.4%). The higher hydroxyethyl starch ratio in total fluid had a negative relationship with the total fluid infusion amount (r = - 0.256, P <  0.001). In multivariable analysis, intraoperatively administered total fluid per weight per hour (odds ratio, 1.248; 95% CI, 1.153-1.351; P <  0.001) and HES-to-crystalloid ratio (odds ratio, 2.125; 95% CI, 1.521-2.969; P <  0.001) were associated with increased risks of postoperative composite outcomes. CONCLUSIONS: Although hydroxyethyl starch administration reduces the total fluid infusion amount during esophageal surgery for cancer, intravenous hydroxyethyl starch infusion is associated with an increasing risk of postoperative composite complications.

The effects of perioperative intravenous fluid administration strategy on renal outcomes in patients undergoing cardiovascular surgery: An observational study.

We assessed whether perioperative fluid management with balanced solutions and a limited volume of hydroxyethyl starch (renal-protective fluid management [RPF] strategy) could improve renal outcomes after cardiovascular surgery.For this retrospective observational study, we evaluated 2613 patients who underwent cardiovascular surgery from January 1, 2010 to December 31, 2013. The control group were given intravenous fluids with saline-based solutions and unlimited volumes of hydroxyethyl starch solutions and the RPF group were given intravenous fluids with RPF. The primary outcome was the incidence of acute kidney injury (AKI) and chronic dialysis within 12 months after cardiovascular surgery. Multivariable regression and propensity analyses were performed to evaluate the association between perioperative fluid management strategy and postoperative renal outcomes.Postoperative AKI and chronic dialysis occurred in 213 (21.2%) and 5 (0.5%) patients in the RPF group compared with 696 (43.2%) and 38 (2.4%) patients in the control group, respectively. After adjustment, the RPF group was linked to a decreased risk of postoperative AKI, severe AKI, persistent AKI, use of renal replacement therapy, chronic kidney disease, chronic dialysis, and a shorter postoperative extubation time and intensive care unit, and hospital stay duration.The perioperative fluid management strategy with balanced solutions and a limited volume of hydroxyethyl starch was related to improved acute and 1-year renal and clinical outcomes after cardiovascular surgery. These findings indicate the need for further definitive clinical trials on perioperative fluid management strategy.

Revealing the Dependence of Molecular-Level Force Transfer and Distribution on Polymer Cross-Link Density via Mechanophores.

The correlation between polymer architecture and molecular-level forces has long been a challenging research subject. Herein, spiropyran, a mechanophore that exhibits fluorescence change under force, was incorporated as a cross-linker between PMMA backbone segments. Using an in situ opto-mechanical setup to probe the molecular-level forces, the mechano-response of SP-linked PMMA as a function of the cross-link density was monitored during deformation. The dependence of the molecular-level force on cross-link density was quantitatively examined and revealed. First, a higher cross-link density shifted the fluorescence onset, that is, the onset of the spiropyran-to-merocyanine transition, to lower strains, eventually shifting the onset long before yield, without requiring sufficient chain mobility, owing to the higher efficiency of the force transfer. Under the same energy, the increase in cross-link density allowed for faster force transfer, but only to a certain level. Finally, the overall amount of spiropyran-to-merocyanine conversion linearly decreased with increasing cross-link density.

Effect of Total Intravenous Anesthesia vs Volatile Induction With Maintenance Anesthesia on Emergence Agitation After Nasal Surgery: A Randomized Clinical Trial.

Importance: Emergence agitation is common after nasal surgery under general anesthesia and may lead to serious consequences for the patient, including an increased risk of injury, pain, hemorrhage, and self-extubation. Despite decades of research, studies on the incidence, risk factors, and prevention of emergence agitation in adult patients are ongoing, and opinions differ on the different effects of inhalation and intravenous anesthesia. Objective: To investigate the effect of anesthetic method on the occurrence of emergence agitation after nasal surgery. Design, Setting, and Participants: This prospective, randomized, single-blind, clinical trial included 80 patients undergoing open rhinoplasty, septoplasty, turbinoplasty, endoscopic sinus surgery, and functional endoscopic sinus surgery under general anesthesia who were randomized to receive total intravenous anesthesia (TIVA) with remifentanil hydrochloride and propofol (n = 40) or volatile induction and maintenance of anesthesia (VIMA) with sevoflurane and nitrous oxide (n = 40) in Asan Medical Center, a tertiary referral center in Seoul, Republic of Korea. Data were collected from August 24 through October 14, 2016, and analyzed from October 26, 2016, through September 14, 2017. Main Outcomes and Measures: The occurrence of emergence agitation defined by the following 2 individual criteria: a Richmond Agitation-Sedation Scale score of at least 1 and a Riker Sedation-Agitation Scale score of at least 5 immediately after extubation. Results: Among the 80 patients included in the analysis (68.8% men [n = 55]; mean [SD] age, 41.6 [17.9] years), emergence agitation measured by the Richmond Agitation Sedation Scale occurred in 8 of 40 patients (20.0%) in the VIMA group and 1 of 40 (2.5%) in the TIVA group. The risk difference was 17.5 (95% CI, 3.6-31.4). Emergence agitation measured by the Riker Sedation-Agitation Scale score occurred in 10 of 40 patients (25.0%) in the VIMA group and 1 of 40 (2.5%) in the TIVA group. The risk difference was 22.5 (95% CI, 7.3-37.7). Conclusions and Relevance: The occurrence of emergence agitation after nasal surgery under general anesthesia can be significantly reduced by using TIVA rather than VIMA. Trial Registration: CRIS identifier: KCT0002145.

Pulmonary aspiration during intubation in a high-risk patient: A video clip and clinical implications.

We report a case of pulmonary aspiration during induction of general anesthesia in a patient who was status post esophagectomy. Sudden, unexpected aspiration occurred even though the patient had fasted adequately (over 13 hours) and received rapid sequence anesthesia induction. Since during esophagectomy, the lower esophageal sphincter is excised, stomach vagal innervation is lost, and the stomach is flaccid, draining only by gravity, the patient becomes vulnerable to aspiration. As the incidence of perioperative pulmonary aspiration is relatively low, precautions to prevent aspiration tend to be overlooked. We present a video clip showing pulmonary aspiration and discuss the literature concerning the risk of aspiration and its preventive strategies.

Prognostic Impacts of Increases in Amino Transaminases Following Coronary Artery Bypass Grafting on Mortality.

OBJECTIVE: To evaluate the prognostic impacts of postoperative increases in serum amino transaminases on 1-year mortality in patients who underwent coronary artery bypass graft. DESIGN: A retrospective analysis. SETTING: A tertiary care university hospital. PARTICIPANTS: A total of 1,950 patients who underwent coronary artery bypass graft. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Aspartate amino transaminase and alanine amino transaminase ratios were calculated as the ratio between the peak aspartate amino transaminase and alanine amino transaminase within the first 5 post-operative days and their respective upper limit of normal values. A ratio of 2.0 was seen to be the minimum for which a difference in 1-year mortality could be detected in univariate analysis, when considering simultaneously both aspartate amino transaminase and alanine amino transaminase ratios. Multivariable analysis showed an association between an aspartate amino transaminase ratio > 2.0 and increased 1-year mortality (hazard ratio [HR] 2.68, 95% confidence interval [CI] 1.42-5.05, P = 0.002), and also between both an aspartate amino transaminase and alanine amino transaminase ratio > 2.0 and increased 1-year mortality (HR 3.90, 95% CI 1.87-8.14, P < 0.001). However, increases in alanine amino transaminase only above the upper limit of normal were not associated with increased 1-year mortality. CONCLUSIONS: Postoperative increases in aspartate amino transaminase only and increases in both aspartate amino transaminase and alanine amino transaminase greater than twice the upper limit of normal were associated with increased 1-year mortality in patients undergoing coronary artery bypass graft.

Impact of anesthetic agents on overall and recurrence-free survival in patients undergoing esophageal cancer surgery: A retrospective observational study.

Given that surgical stress response and surgical excision may increase the likelihood of post-surgery cancer dissemination and metastasis, the appropriate choice of surgical anesthetics may be important for oncologic outcomes. We evaluated the association of anesthetics used for general anesthesia with overall survival and recurrence-free survival in patients who underwent esophageal cancer surgery. Adult patients (922) underwent elective esophageal cancer surgery were included. The patients were divided into two groups according to the anesthetics administered during surgery: volatile anesthesia (VA) or intravenous anesthesia with propofol (TIVA). Propensity score and Cox regression analyses were performed. There were 191 patients in the VA group and 731 in the TIVA group. In the entire cohort, VA was independently associated with worse overall survival (HR 1.58; 95% CI 1.24-2.01; P < 0.001) and recurrence-free survival (HR 1.42; 95% CI 1.12-1.79; P = 0.003) after multivariable analysis adjustment. Similarly, in the propensity score matched cohorts, VA was associated with worse overall survival (HR 1.45; 95% CI 1.11-1.89; P = 0.006) and recurrence-free survival (HR 1.44; 95% CI 1.11-1.87; P = 0.006). TIVA during esophageal cancer surgery was associated with better postoperative survival rates compared with volatile anesthesia.