Quantitative evaluation of the effects of interscalene block on physiological responses to the balance between nociception and anti-nociception among inpatients undergoing total shoulder arthroplasty under general anesthesia.

Although the suppression of physiological responses to the balance between nociception caused by surgical trauma and anti-nociception due to anesthesia during total shoulder arthroplasty (TSA) is relevant for better perioperative managements, quantitative evaluations of the effects of ultrasound-guided interscalene brachial plexus block (ISB) on physiological responses have not been performed. Physiological responses were assessed using the nociceptive response (NR) index. In this multi-institutional observational study, associations between ISB and NR values were examined among inpatients undergoing TSA under general anesthesia between March 2019 and January 2021. The effects of ISB on acute postoperative pain and major complications within 30 days after surgery were also examined. NR values after skin incision clearly showed significant suppressions of physiological responses in patients undergoing TSA with ISB (n = 60), compared to those without ISB (n = 24). Acute postoperative pain on the day of surgery was also significantly less in patients with ISB than in those without ISB. Postoperative complications, classified by Clavien-Dindo grades, showed no significant differences between patients with and without ISB. A propensity score-matched sensitivity analysis confirmed the same results in patients with (n = 21) and without ISB (n = 21). In conclusion, suppression of physiological responses to the balance between nociception and anti-nociception by ISB can be quantitatively evaluated by NR index during TSA.

Intra-operative nociceptive responses and postoperative major complications after gastrointestinal surgery under general anaesthesia: A prospective cohort study.

BACKGROUND: Surgical procedures stimulate nociception and induce physiological responses according to the balance between nociception and antinociception. The severity of surgical stimuli is associated with major postoperative complications. Although an intra-operative quantitative index representing surgical invasiveness would be useful for anaesthetic management to predict and prevent major complications, no such index is available. OBJECTIVES: To identify associations between major complications after gastrointestinal surgery and intra-operative quantitative values from intra-operative nociception monitoring. DESIGN: A multi-institutional observational study. SETTING: Two university hospitals. PATIENTS: Consecutive adult patients undergoing gastrointestinal surgery under general anaesthesia. MAIN OUTCOME MEASURES: Averaged values of nociceptive response index from start to end of surgery (mean NR index) and risk scores of the Surgical Mortality Probability Model (S-MPM) were calculated. Pre and postoperative serum C-reactive protein (CRP) levels were obtained. After receiver-operating characteristic (ROC) curve analysis, all patients were divided into groups with high and low mean nociceptive response index. Associations between mean nociceptive response index and postoperative major complications, defined as Clavien-Dindo grade at least IIIa, were examined using logistic regression analysis. RESULTS: ROC curve analysis showed a nociceptive response index cut-off value for major complications of 0.83, and we divided patients into two groups with mean nociceptive response index less than 0.83 and at least 0.83. The incidence of major complications was significantly higher in patients with mean nociceptive response index at least 0.83 (23.1%; n = 346) than in patients with mean nociceptive response index less than 0.83 (7.7%; n = 443; P < 0.001). Multivariate analysis revealed emergency surgery, S-MPM risk score, mean nociceptive response index and postoperative CRP levels as independent risk factors for major complications. CONCLUSION: Mean nociceptive response index during surgery likely correlates with major complications after gastrointestinal surgery. TRIAL REGISTRATION: The current observational study had no intervention, and was therefore, not registered.

Association between intraoperative nociception and surgical invasiveness in patients undergoing non-cardiac surgery under general anesthesia: a retrospective cohort study.

There are several indexes of intraoperative nociception during surgery under general anesthesia. Although a higher degree of surgical invasiveness increases intraoperative nociception, an association between the index of intraoperative nociception and severity of surgical invasiveness has not been reported. We hypothesized that there is associations between averaged values of nociceptive response (NR) throughout surgery (mean NR), as the index of intraoperative nociception, and surgical severity codes in the Surgical outcome risk tool (SORT) or procedure risk codes in the Surgical mortality probability model (S-MPM). The primary outcome was the association between mean NR and severity scores of surgical procedure. Hence, a single institutional retrospective cohort study was performed in consecutive patients undergoing non-cardiac surgery under general anesthesia from June 2018 to May 2019. There were significant increases in the three categories of procedure risk in the S-MPM corresponding to the increase in mean NR values in 5090 patients. In the SORT, the highest intensity in the four categories of surgical severity also significantly correlated with the increase in mean NR values. Increasing intensity of intraoperative nociception is likely associated with higher severity codes of surgical invasiveness in prediction models for postoperative morbidity and mortality.

Effects of anaesthesia-induced hypotension and phenylephrine on plasma volume expansion by hydroxyethyl starch: A randomised controlled study.

BACKGROUND: Changes in blood haemoglobin concentration indicate plasma volume expansion following hydroxyethyl starch (HES) infusion, but may be affected by vascular tone and HES-induced shedding of the endothelial surface layer (ESL). We hypothesised that anaesthesia-induced hypotension enhances changes in plasma volume as assessed by blood haemoglobin concentration (ΔPVHb , %) following HES infusion. METHODS: Fifty-two patients undergoing abdominal surgery were randomised to receive a continuous infusion of saline (S group) or phenylephrine to restore vascular tone (P group) (n = 26 each). Both groups received an infusion of 8 mL/kg 6% HES solution after induction of general anaesthesia. We compared ΔPVHb at the end of fluid infusion (15 minutes) and 15 minutes later (30 minutes) between the two groups. We assessed changes in ESL structure by measuring plasma concentrations of hyaluronate and syndecan-1. P < .05 was considered statistically significant. RESULTS: Mean arterial blood pressure was lower in the S group approximately by 30-40% compared to the P group (P < .001). ΔPVHb was larger in the S group compared to the P group at 15 minutes (24.9 [5.2] % vs 19.0 [5.2] %; P < .001) and 30 minutes (26.5 [5.9] % vs 16.9 [6.6] %; P < .001). There were no clinically significant differences in plasma concentrations of hyaluronate and syndecan-1 with time and between the groups. CONCLUSIONS: Increased volume expansion of circulating plasma following HES infusion in anaesthesia-induced hypotension compared to when blood pressure is restored by phenylephrine may result from an attenuation of transcapillary fluid filtration, rather than ESL shedding. UMIN Clinical Trial Registration Number: UMIN000017394 (http://www.umin.ac.jp/ctr/index.htm).

Association between intraoperative nociception and postoperative complications in patients undergoing laparoscopic gastrointestinal surgery.

A higher degree of surgical invasiveness, which increases intraoperative nociception, might induce postoperative complications. Although several nociceptive indices for use during surgery are available in clinical practice, association between intraoperative nociception and postoperative complications has not been reported. An index representing intraoperative nociception, which is the averaged value of Nociceptive Response throughout the surgery (mean NR) was applied to examine the association in the present study. The retrospective study evaluated consecutive adult patients undergoing laparoscopic gastrointestinal surgery, American Society of Anesthesiologists-physical status (ASA-PS) I or II, whose preoperative C-reactive protein level was < 0.3 mg dL-1. We first used ordinal logistic analysis to examine the association between preoperative and intraoperative risk factors and complications graded by the Clavien-Dindo classification. Next, we performed propensity score matched analysis to evaluate the effects of mean NR throughout surgery on postoperative complications. Ordinal logistic analysis (n = 158) revealed that duration of surgery (P < 0.001), mean NR during surgery (P = 0.002), and ASA-PS (P = 0.016) were risk factors for postoperative complications. Then all patients were divided into two propensity score matched groups, based on a mean NR of < 0.85 and ≥ 0.85, with matching for age, ASA-PS, body mass index and duration of surgery. The severity of postoperative complications was significantly higher in the high NR group than in the low NR group (P = 0.005). In conclusion, there was likely an association between intraoperative nociception and postoperative complications in patients without serious preoperative conditions and comorbidities.

Effects of Thoracic Paravertebral Block on Nociceptive Levels After Skin Incision During Video-Assisted Thoracoscopic Surgery.

BACKGROUND Regional anesthesia provides excellent analgesic effects after surgery. However, the effects of regional anesthesia on nociceptive levels during surgery under general anesthesia have not been quantitatively evaluated. To reveal the effects of thoracic paravertebral block (PVB) on nociceptive levels after skin incision during general anesthesia, we performed a retrospective cohort study in patients without serious preoperative conditions or comorbidities undergoing elective video-assisted thoracoscopic surgery (VATS). Nociceptive levels during general anesthesia were calculated using our previously determined Nociceptive Response (NR) equation, which utilizes common hemodynamic parameters. MATERIAL AND METHODS Data on 77 adult patients who underwent VATS from May 2018 to August 2018 were retrospectively obtained from our institutional database. We then performed propensity score matching between patients who received thoracic PVB (PVB group: n=29) and those who did not (Control group: n=48). The averaged values of systolic blood pressure (SBP), heart rate (HR), perfusion index (PI), bispectral index (BIS), and NR from 10 to 5 minutes before skin incision (T0), 5 to 10 minutes (T1), 10 to 15 minutes (T2), 15 to 20 minutes (T3), and 20 to 25 minutes after skin incision (T4), were calculated. RESULTS Twenty-four propensity score-matched patients in each group were analyzed. Mean NR values at T1 and T2 in the PVB group were significantly lower than those in the Control group. SBP, HR, PI, and BIS, however, showed no significant differences between the 2 groups, except for SBP at T2. CONCLUSIONS Thoracic PVB prevented an increase in NR values, which quantitatively represent nociceptive levels under general anesthesia, in patients undergoing VATS.

Complex effects of continuous vasopressor infusion on fluid responsiveness during liver resection: A randomised controlled trial.

BACKGROUND: Fluid responsiveness is an important factor to consider for fluid volume loading during major surgery. The effect of continuous vasopressor infusion on fluid responsiveness during prolonged major surgery is a concern. OBJECTIVE: We hypothesised that continuous vasopressor infusion during major surgery might not exert significant effects on changes in stroke volume variation (SVV) following fluid bolus infusion, and thereby on fluid responsiveness. DESIGN: Randomised controlled trial. SETTING: University hospital from April 2014 to August 2016. PATIENTS: Patients undergoing liver resection who were randomised to receive continuous intravenous infusion of phenylephrine (P group), norepinephrine (N group), or no vasopressor (C group) (n=17/group). Exclusion criteria were cardiac arrhythmia and severe cardiac, pulmonary or renal dysfunction. INTERVENTION: Patients received 4 ml kg fluid boluses of 6% hydroxyethyl starch solution when SVV was at least 12%. Vasopressors were administered continuously to maintain the systemic vascular resistance index at more than 1900 dyn s cm m. MAIN OUTCOME MEASURES: Cardiac index and SVV were measured using the FloTrac/Vigileo system (Version 4.00). The number of fluid boluses with fluid responsiveness (i.e. >15% increase in cardiac index) was compared between groups using multilevel logistic regression analysis. RESULTS: Numbers of fluid responsive boluses in the C, P and N groups were 12 (14%), 22 (34%) and 19 (27%), respectively. Odds ratios on fluid responsiveness for phenylephrine and norepinephrine compared with the control were 3.65 (97.5% confidence interval, 1.15 to 11.6; P = 0.012) and 2.56 (97.5% confidence interval, 0.82 to 8.00; P = 0.064), respectively. Decreases in SVV after fluid bolus infusion for the P and N groups were comparable with the C group (P = 0.23 and 0.53, respectively). CONCLUSION: Continuous administration of phenylephrine increased fluid responsiveness during liver resection, suggesting complex effects of continuous vasopressor infusion involving changes in cardiac preload and afterload. TRIAL REGISTRATION: UMIN000011024.

Development of a Hemodynamic Model Using Routine Monitoring Parameters for Nociceptive Responses Evaluation During Surgery Under General Anesthesia.

BACKGROUND Routine hemodynamic monitoring parameters under general anesthesia, such as heart rate (HR), systolic blood pressure (SBP), and perfusion index (PI), do not solely reflect intraoperative nociceptive levels. We developed a hemodynamic model combining these 3 parameters for nociceptive responses during general anesthesia, and evaluated nociceptive responses to surgical skin incision. MATERIAL AND METHODS We first retrospectively performed discriminant analysis using 3 values - HR, SBP, and PI - to assess response to skin incision during tympanoplasty, laparoscopic cholecystectomy, and open gastrectomy to determine if combined use of these parameters differentiates nociceptive levels among these 3 surgeries. Secondly, ordinal logistic regression analysis was applied using the 3 parameters to develop an equation representing nociceptive response during general anesthesia, and then evaluated its utility to discern nociceptive responses to skin incision. RESULTS We developed the following hemodynamic model as calculated nociceptive response= -1+2/(1+ exp(-0.01 HR -0.02 SBP +0.17 PI)), and prospectively determined that calculated nociceptive responses to small skin incision for laparoscopic surgery were significantly lower than responses to large skin incision for laparotomy. CONCLUSIONS Our hemodynamic model using HR, SBP, and PI likely reflects nociceptive levels at skin incision during general anesthesia, and quantitatively discerned the difference in nociceptive responses to skin incision between laparoscopy and laparotomy. This model could be applicable to assess either real-time nociceptive responses or averaged nociceptive responses throughout surgery without using special equipment.

[Simulation Training for Critical Obstetric Hemorrhage in Cesarean Section for Medical Students with Human Patient Simulator (HPS®), Comparison between Role-play and Impromptu Simulation[.

BACKGROUND: The simulation training for critical obstetric hemorrhage for medical students, lacks a gold standard, but should be effectively performed. To opti- mize the simulation for critical obstetric hemorrhage with human patient simulator (HPS® Human Patient Simulator Muse2.1, CAE Healthcare, Quebec, Canada), we assessed the effectiveness of impromptu simulation and role-play simulation among fifth-year medical stu- dents. METHODS: The role-play simulation among 49 medi- cal students, of obstetric critical hemorrhage in Cesar- ean section was compared with the learning effect of the unprepared impromptu simulation among other 49 medical students. (observational cohort study). The effects of simulation training was assessed with pre and post numbers of answers for the question "the management items for critical obstetric hemorrhage in cesarean section". RESULTS: The items of answer pre- and post-simula- tion were, oxygen administration, uterotonic drugs, infusion, preparation of the blood products, blood sam- ple examination, cross-matching test ensuring of the manpower, plasma substitute administration, vasopres- sors, blood transfusion, intraoperative blood salvage, interventional radiology, arterial line, central venous catheter, airway management general anesthesia and total hysterectomy. Simulation provided a learning effect for these items. In impromptu simulation, the numbers of answers per one medical student were increased from 2.3 ±1.4 to 7.0±3.0 items (P<0.0001). In another role-play simulation, those were increased from 2.1±1.8 to 5.6±2.3 items (P<0.0001). CONCLUSIONS: The impromptu simulation was con- sidered to have a superior learning effect than role-play simulation.

Comparison of the level of intraoperative nociception between laparoscopic and open hepatic resection.

BACKGROUND/AIMS: Sufficient suppression of perioperative nociception is important for ensuring favorable postoperative outcomes. Although the level of nociception during laparoscopic surgery is generally lower than during laparotomy, there is insufficient evidence to support this for hepatic resection. METHODOLOGY: To develop a method to retrospectively evaluate the intraoperative nociceptive level, we collected data of intraoperative averaged values of heart rate, perfusion index, systolic blood pressure during three surgeries with different levels of intraoperative nociception. After we validated the utility of discriminant analysis using these variables for the retrospective evaluation of nociception during surgery, we performed this analysis in patients who underwent either laparoscopic or open hepatic resection. RESULTS: Although there was a significant difference in discriminant score between the open and the laparoscopic hepatic resection groups before propensity score matching, discriminant score showed no significant difference between two groups after matching. CONCLUSIONS: The level of nociception during laparoscopic hepatic resection is likely similar to that during open hepatic resection. An assertive anti-nociceptive strategy might be required for laparoscopic procedures under general anesthesia, as with open procedures.

Preoperative anxiety induces no clinically relevant effect on intraoperative nociceptive levels during breast surgery under general anesthesia.

Anxiety can affect acute and chronic postoperative pain after breast surgery. Nociceptive response during surgery might also be affected by preoperative anxiety even under unconscious state during general anesthesia. The aim of this retrospective study was to investigate nociceptive responses during breast surgery under general anesthesia in patients with or without preoperative anxiety. Patients (n = 45) were divided into a low-anxiety group (n = 25) and a high-anxiety group (n = 20) in accordance with preoperative scores for the State Trait Anxiety Inventory. We performed discriminant analysis to compare nociception during surgery using three intraoperative averaged values: heart rate; systolic blood pressure; and perfusion index. No significant differences in discriminant score were seen between groups (p = 0.10). Although we performed propensity score-matching to reduce the bias due to confounding variables in this retrospective study, there was also no significant difference in levels of nociceptive response between groups (p = 0.06). In conclusion, the level of nociception during breast surgery is not significantly affected by preoperative anxiety.

Preoperative oral rehydration solution intake volume does not affect relative change of mean arterial blood pressure and crystalloid redistribution during general anesthesia in low-risk patients: an observational cohort study.

Despite the implementation of liberal preoperative fasting routines, it is unclear whether preoperative oral rehydration solution intake volume affects blood pressure during general anesthesia. We enrolled 60 patients (American Society of Anesthesiologists status I/II) undergoing tympanoplasty. Patients drank 200-1,000 ml oral rehydration solution until 2-3 h before anesthesia induction. Anesthesia was induced by propofol and maintained with sevoflurane and remifentanil. Coinciding with anesthesia induction, 15 ml/kg Ringer's acetate solution was administered intravenously over 60 min followed by 1 ml/kg Ringer's acetate solution over the next 30 min. Mean arterial blood pressure (MAP) and whole-body bioelectrical resistance for extracellular fluid (R e) during anesthesia were compared between retrospectively classified intake groups of oral rehydration solution. There were no differences in mean MAP during the 30-90 min period relative to baseline [0.67 (0.60-0.74), 0.65 (0.61-0.76), 0.64 (0.60-0.70), P = 0.96] and relative R e at 90 min [0.945 (0.018), 0.944 (0.021), 0.943 (0.021), P = 0.95] between the small (n = 14), intermediate (n = 29), and large (n = 17) intake groups. The intake volume of preoperative oral rehydration solution does not affect the magnitude of hypotension during general anesthesia in low-risk patients undergoing minor surgery.

Effect of decreased fetal perfusion on placental clearance of volatile anesthetics in a dual perfused human placental cotyledon model.

Placental transfer of volatile anesthetics is a critical issue in managing fetal distress during cesarean section under general anesthesia. Using dual perfused human placental cotyledons obtained from parturients undergoing elective cesarean section (n = 5), we investigated the effect of decreased fetal perfusion on placental clearance of sevoflurane and isoflurane. Keeping the maternal flow rate fixed, fetal flow rate was consecutively decreased from 3 ml/min (control perfusion) to 2 ml/min (intermediate perfusion) and to 1 ml/min (hypoperfusion). Placental transfer was assessed by the clearance of anesthetics by the placenta, defined by the ratio of anesthetic concentration in fetal vein and maternal artery, multiplied by fetal flow rate. Placental clearance was compared between different fetal perfusion states and anesthetics. Hypoperfusion resulted in a lower clearance of sevoflurane and isoflurane compared with control (P = 0.002, P < 0.001) and intermediate (P = 0.04, P = 0.018) perfusion. Clearances of sevoflurane and isoflurane were comparable during control perfusion (P = 0.93), intermediate perfusion (P = 1.00), and hypoperfusion (P = 0.88). Thus, maintenance of volatile anesthetics at a marginally low concentration may not be necessary when fetal distress is observed during emergency cesarean delivery because placental transfer of volatile anesthetics decreases with decreasing fetal perfusion.

[Air-Q® intubating laryngeal airway as a conduit for tracheal intubation in a patient with Apert syndrome: a case report].

We present a case of an 18-year-old male who underwent strabismus operation under general anesthesia. In his childhood, tracheostomy had been performed for the repair of cleft lip and palate. His Mallampati classification was IV and preoperative endoscopic examination revealed megaloglossia and severe airway narrowing. For possible difficult airway, intubating laryngeal airway (air-Q®, size 2.5) was used for tracheal intubation. Following insertion of air-Q®, trachea was intubated via air-Q® guided with fiberscope. The patient was ventilated via tracheal tube with the air-Q® remaining in place during the operation. air-Q® can be effectively utilized for airway management for an adult Apert syndrome patient

Protein sparing during general anesthesia with a propofol solution containing medium-chain triglycerides for gastrectomy: comparison with sevoflurane anesthesia.

PURPOSE: Despite the importance of the inhibition of catabolic response to surgery, the effects of different anesthetic techniques on the catabolic response in surgical patients are controversial. This study compared the endocrine-metabolic responses and protein catabolism during gastrectomy in patients who received either sevoflurane or propofol anesthesia with remifentanil. METHODS: Thirty-seven patients (American Society of Anesthesiologists status I-III) aged 20-79 years undergoing elective gastrectomy were randomly assigned to receive sevoflurane anesthesia with remifentanil (n = 19) or intravenous propofol anesthesia (Propofol-Lipuro(®) 1 %; B. Braun, Melshungen AG, Germany) with remifentanil (n = 18). Urine samples were collected every 1 h after skin incision (0 h) and the urinary 3-methylhistidine:creatinine ratio (3-MH/Cr ratio) was used as a marker of protein catabolism. Respiratory quotient was measured during a 1 h period following skin incision. RESULTS: The 3-MH/Cr ratio significantly increased at 1-2 and 2-3 h compared to 0 and 0-1 h in both groups, but the propofol group exhibited a lower 3-MH/Cr ratio (nmol/µmol) than the sevoflurane group at 1-2 h (15.7 vs. 18.2, P = 0.012) and 2-3 h (15.9 vs. 18.1, P = 0.025). A difference was observed in the respiratory quotient between the sevoflurane and propofol groups (0.726 vs. 0.707, P = 0.003). CONCLUSION: A lower 3-MH/Cr ratio and a lower respiratory quotient during propofol anesthesia, compared to those exhibited during sevoflurane anesthesia, suggest that protein sparing probably occurs through the utilization of medium-chain triglycerides contained in the fat emulsion of propofol solution as a fuel source.

[A case of awake intubation using the Pentax-AWS airwayscope in a patient with a difficult airway combined with severe hemorrhagic shock].

We report a case of awake intubation in a patient with a difficult airway combined with severe hemorrhagic shock using the Pentax-AWS Airwayscope (AWS). A 65-year-old man experienced severe hemorrhagic shock due to diaphragmatic hernia after extrapleural pneumonectomy and was scheduled for emergent exploratory thoracotomy under general anesthesia. Blood pressure was maintained with dopamine-noradrenaline support, and rapid transfusion. We anticipated difficult ventilation due to a swollen face and tongue. The patient underwent awake intubation with the AWS under dexmedetomidine sedation and lidocaine spray for laryngotracheal anesthesia. The patient did not buck during intubation and hemodynamic changes were minimal.

[Application of air-Q laryngeal airway and gum elastic bougie in a case of anticipated difficult. Mask ventilation and tracheal intubation in a man with morbid obesity].

A 46-year-old man was diagnosed with descending colon cancer and was planned to undergo left hemicolectomy under general anesthesia. His body mass index was 42.6 and due to his small mouth and jaw, we anticipated difficult mask ventilation and tracheal intubation. To avoid 'can't ventilate, can't intubate', we first inserted a size 3.5 air-Q laryngeal airway under moderate sedation, maintaining spontaneous ventilation. After confirming sufficient assisted ventilation, we used a bronchofiberscope to visualize placement of a gum elastic bougie in the trachea via the air-Q. Then, we replaced the air-Q with an outside diameter 8.5 mm tracheal tube. This case was a successful use of the air-Q under moderate sedation for airway management in the setting of anticipated difficult mask ventilation and tracheal intubation.

[Complementary use of central venous oxygen saturation for fluid management in abdominal surgery patients with severely compromised cardiac function: a report of two cases].

Perioperative fluid management for cases with severely compromised cardiac function undergoing major non-cardiac surgery remains a challenge. Dynamic parameters such as stroke volume variation (SVV) and cardiac index obtained by arterial pulse contour analysis may not be sufficient for fluid optimization because individualized optimal parameter values are difficult to determine in cardiac patients. We report two cases of abdominal surgery with severe pre-existing impairment of cardiac function (ejection fraction < 30%) complicated by severe pulmonary and renal dysfunction. In Case 1, because of unreliably high SVV values due to a sudden onset of cardiac arrhythmia, we performed colloid bolus infusion targeting central venous oxygen saturation (ScvO2) above 80%. In Case 2, cardiac index and stroke volume index remained unchanged despite the decrease of SVV after colloid bolus infusion. Infusion of dobutamine was useful for maintaining the ScvO2 above 75% in a rather hypovolemic state (SVV of 10-15%). Our cases suggest that the use of central venous oxygen saturation together with arterial pulse contour analysis may aid decision-making for individualized fluid optimization and use of inotropics in severely compromised cardiac patients undergoing major abdominal surgery.

[Anesthesia for tracheal metal stent management utilizing venovenous extracorporeal life support].

We report a successful case of metal stent replacement utilizing venovenous extracorporeal life support (VV-ECLS). A 71-year-old woman, who had previously undergone tracheal metal stent placement, encountered dyspnea associated with inversion of the stent. Metal stent replacement was planned under general anesthesia. After securing the VV-ECLS in the right and left femoral vein, anesthesia was induced with propofol and remifentanil. Metal stent replacement was conducted under rigid and flexible bronchoscope through the tracheal tube. Oxygenation and carbon dioxide excretion were achieved uneventfully. VV-ECLS was considered useful for the management of subglottic difficult airway such as complex tracheal stenosis.