Pharmacodynamic analysis of intravenous bolus remimazolam for loss of consciousness in patients undergoing general anaesthesia: a randomised, prospective, double-blind study.

BACKGROUND: Remimazolam is a new rapid offset benzodiazepine used for procedural sedation and general anaesthesia. This study evaluated the efficacy and safety of i.v. bolus remimazolam during induction of anaesthesia. METHODS: A total of 120 patients undergoing general anaesthesia were randomly allocated into six dose groups (n=20) of i.v. bolus remimazolam (0.02-0.27 mg kg-1). Loss of consciousness, respiratory depression, patient state index (PSI), and haemodynamic variables were evaluated during anaesthetic induction. Parametric time-to-event models were used to identify the 50% effective dose (ED50)/95% effective dose (ED95) associated with loss of consciousness and respiratory depression. Non-linear mixed-effect models analysed the PSI and haemodynamic changes after i.v. bolus remimazolam. RESULTS: Loss of consciousness and respiratory depression onset showed steep dose-responses with ED50/ED95 of 0.11/0.19 and 0.14/0.27 mg kg-1 and Hill coefficients of 5.3 and 4.6, respectively. Older age was significantly associated with lower ED50/ED95 for both endpoints. ED50/ED95 and the Hill coefficient of PSI decline were 0.12/0.68 mg kg-1 and 1.7, respectively. We propose optimal doses of 0.25-0.33, 0.19-0.25, and 0.14-0.19 mg kg-1 in patients aged <40, 60-80, and >80 yr, respectively, based on the ED95 estimates for the corresponding age groups. The maximum percentage reduction of MAP was 27.8% and the ED50/ED95 were 0.14/2.60 mg kg-1. The effect of remimazolam on heart rate was insignificant. CONCLUSIONS: The ED50/ED95s of i.v. bolus remimazolam were successfully estimated from the time to loss of consciousness and respiratory depression. No serious adverse events occurred within the range of tested doses. CLINICAL TRIAL REGISTRATION: NCT04901871.

Stabilization and Tracking of a Quadrotor Using Modified Sigmoid Sliding Mode Control.

A modified sigmoid sliding mode control (MS-SMC) approach is proposed for stabilizing and tracking a quadrotor system with a nonlinear sliding surface, where the dynamics model is underactuated, highly coupled, and nonlinear. The constructed nonlinear sliding surface is based on the traditional sliding mode surface with a modified sigmoid function, allowing the initial value to quickly reach equilibrium. A new type of nonlinear SMC is applied for performance improvement of the quadrotor using the proposed modified sigmoid sliding surface. To control the quadrotor effectively, a double-loop control method is used to design the control rate, in which the position subsystem is the outer loop, and the attitude subsystem is the inner loop.With the Lyapunov function, the stability of the overall closed-loop system is ensured by stabilizing each subsystem step by step. Moreover, from a practical point of view, the system performance under the model uncertainties and external disturbances are also considered. The simulation results show that the proposed MS-SMC performs better than the conventional sliding mode control (CSMC) and the back-stepping sliding mode control (BS-SMC) in terms of stabilization and tracking against external disturbances.

Experimental Validation of High Precision Web Handling for a Two-Actuator-Based Roll-to-Roll System.

In this paper, experimental validation of high precision web handling for a two-actuator-based roll-to-roll (R2R) system is presented. To achieve this, the tension control loop is utilized to regulate the tension in the unwinder module, and the velocity loop is utilized to regulate the web speed in the rewinder module owing to the limitation of the number of actuators. Moreover, the radius estimation algorithm is applied to achieve an accurate web speed and the control sequence of the web handling in the longitudinal axis is developed to manipulate the web handling for convenience. Having these, the tension control performances are validated within ±0.79, ±1.32 and ±1.58 percent tension tracking error and 1.6, 1.53 and 1.33 percent web speed error at the speeds of 0.1 m/s, 0.2 m/s, and 0.3 m/s, respectively. The tension control performance is verified within ±0.3 N tracking error in the changes of the reference tension profile at 0.1 m/s web speed. Lastly, the air floating roller is used to minimize the friction terms and the inertia of the idle roller in the tension zone so that tension control performance can be better achieved during web transportation.

Effect of chlorpheniramine administration on postoperative catheter-related bladder discomfort in patients undergoing transurethral excision of bladder tumor: a prospective randomized study.

PURPOSE: Catheter-related bladder discomfort (CRBD) is postoperative distress caused by a urinary catheter. CRBD is related to muscarinic receptor activation. Chlorpheniramine has antimuscarinic properties. Hence, this investigation was undertaken to evaluate the efficacy of chlorpheniramine in preventing CRBD in patients undergoing transurethral resection of bladder tumor (TURBT). METHODS: Seventy-six patients scheduled for TURBT under general anesthesia were assigned into two groups. In the chlorpheniramine group (n = 38), 100 ml normal saline containing 0.1 mg/kg chlorpheniramine was infused after general anesthesia induction. In the control group (n = 38), 100 ml normal saline alone was infused. The incidence and severity of CRBD were assessed at 1, 6, and 24 h postoperatively. RESULTS: The 1-h postoperative incidence of CRBD was lower in the chlorpheniramine group based on the unadjusted analysis [16 (42%) vs. 28 (74%), risk difference 32%, 95% confidence interval 8-51, p = 0.005]. After adjusting the size of the urinary catheter, post hoc analysis showed that the 1-h postoperative incidence of CRBD was lower in the chlorpheniramine group (p = 0.004). The CRBD severity score was lower in the chlorpheniramine group at 1 and 6 h after operation based on the unadjusted analysis (p = 0.012 and p = 0.007, respectively). After adjusting the urinary catheter size, post hoc analysis showed that 1- and 6-h CRBD severity score was lower in the chlorpheniramine group (p = 0.012 and p = 0.008, respectively). The incidence of rescue medication was lower in the chlorpheniramine group [10 (26%) vs. 20 (53%), risk difference 26%, 95% confidence interval 3-47, p = 0.019]. The overall incidence of complications such as nausea, vomiting, dry mouth, flushing, dizziness, and blurred vision was comparable between the two groups. CONCLUSIONS: Chlorpheniramine administration significantly reduces the incidence and severity of CRBD in the patients undergoing TURBT. TRIAL REGISTRATION: KCT0004880 ( https://cris.nih.go.kr/ ).

Two-handed jaw thrust decreases postoperative sore throat in patients undergoing double-lumen endobronchial intubation: A randomised study.

BACKGROUND: Tracheal intubation using a double-lumen endobronchial tube (DLT) causes postoperative sore throat. OBJECTIVE: To determine the effect of two-handed jaw thrust on postoperative sore throat in patients requiring insertion of a DLT. DESIGN: A randomised study. SETTING: A tertiary teaching hospital from December 2017 to May 2018. PATIENTS: One-hundred and six patients undergoing one-lung anaesthesia. INTERVENTIONS: Patients were allocated to one of two groups (n=53 each). In the jaw thrust group, the two-handed jaw thrust manoeuvre was applied at intubation and advancement of the DLT. In the control group, conventional intubation with a sham jaw thrust was performed. MAIN OUTCOME MEASURES: Incidence of sore throat at 1, 6 and 24 h postoperatively. RESULTS: The incidence of sore throat at 6 h postoperatively was higher in the control group than in the jaw thrust group [31 (59%) vs. 14 (26%), risk ratio (95% confidence interval) 0.45 (0.27 to 0.75), P < 0.01]. The overall incidence of sore throat was higher in the control group than in the jaw thrust group [35 (66%) vs. 18 (34%), risk ratio (95% confidence interval) 0.51 (0.34 to 0.78), P < 0.01]. CONCLUSION: The jaw thrust manoeuvre can reduce the incidence of sore throat in patients undergoing DLT insertion for one-lung ventilation. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03331809.

Influence of intraoperative sevoflurane or desflurane on postoperative sore throat: a prospective randomized study.

PURPOSE: Tracheal intubation for general anesthesia causes postoperative sore throat. The purpose of this study was to evaluate the effect of sevoflurane and desflurane on prevalence of postoperative sore throat in patients after general anesthesia. METHODS: Ninety-six patients scheduled for orthopedic lower extremity surgery under general anesthesia were assigned to sevoflurane group or desflurane group. In the sevoflurane group (n = 48), sevoflurane was used as a maintenance anesthetic agent. In the desflurane group (n = 48), desflurane was used. Prevalence of sore throat, number of patients with rescue analgesics, and analgesics requirements were evaluated. RESULTS: The overall prevalence of postoperative sore throat in the sevoflurane group was lower than that in the desflurane group [21 (44%) vs. 32 (67%), p = 0.024]. The prevalence of sore throat at postoperative 4 h in the sevoflurane group was lower than that in the desflurane group [6 (13%) vs. 18 (38%), p = 0.005]. The number of patients requiring rescue analgesics was lower in the sevoflurane group [25 (52%) vs. 36 (75%), p = 0.020]. The requirement of diclofenac was also lower in the sevoflurane group (30 ± 37 mg vs. 47 ± 40 mg, p = 0.031). CONCLUSIONS: We have shown that sevoflurane was associated with less frequent sore throat than desflurane in patients undergoing orthopedic lower extremity surgery.

Defect-Free, Highly Uniform Washable Transparent Electrodes Induced by Selective Light Irradiation.

A simple route to fabricate defect-free Ag-nanoparticle-carbon-nanotube composite-based high-resolution mesh flexible transparent conducting electrodes (FTCEs) is explored. In the selective photonic sintering-based patterning process, a highly soft rubber or thin plastic substrate is utilized to achieve close and uniform contact between the composite layer and photomask, with which uniform light irradiation can be obtained with diminished light diffraction. This well-controlled process results in developing a fine and uniform mesh pattern (≈12 µm). The mesh patternability is confirmed to be dependent on heat distribution in the selectively light-irradiated film and the pattern design for FTCE could be adopted for more precise patterns with desired performance. Moreover, using a very thin substrate could allow the mesh to be positioned closer to the strain-free neutral mechanical plane. Due to strong interfacial adhesion between the mesh pattern and substrate, the mesh FTCE could tolerate severe mechanical deformation without performance degradation. It is demonstrated that a transparent heater with fine mesh patterns on thin substrate can maintain stability after 100 repeated washing test cycles in which a variety of stress situations occurring in combination. The presented highly durable FTCE and simple fabrication processes may be widely adoptable for various flexible, large-area, and wearable optoelectronic devices.

Effects of calcium chloride coadministered with neostigmine on neuromuscular blockade recovery: A double-blind randomised study.

BACKGROUND: Ionised calcium plays an important role in neuromuscular transmission, but its effects on the reversal of nondepolarising neuromuscular blockade have not been fully evaluated. OBJECTIVE: We examined whether calcium chloride coadministered with neostigmine could enhance the rate of neuromuscular recovery. DESIGN: Randomised double-blind trial. SETTING: A tertiary teaching hospital. PATIENTS: In total, 53 patients undergoing elective surgery under general anaesthesia with neuromuscular monitoring by acceleromyography using a TOF-Watch SX monitor. INTERVENTIONS: Patients were randomly allocated to receive either 5 mg kg of calcium chloride (calcium group, n = 26) or the same volume of normal saline (control group, n = 27) coadministered with 25 µg kg of neostigmine and 15 µg kg of atropine at the end of surgery. MAIN OUTCOME MEASURES: The primary end point was the neuromuscular recovery time [time from neostigmine administration to recovery of the TOF ratio (TOFr) to 0.9]. Secondary end points included the TOFr at 5, 10 and 20 min after neostigmine administration and the incidence of postoperative residual curarisation (PORC), defined as a TOFr less than 0.9 at each time point. RESULTS: The neuromuscular recovery time was significantly faster in the calcium group than in the control group (median [Q1 to Q3]; 5.0 [3.0 to 7.0] vs. 6.7 [5.7 to 10.0] min, respectively; P = 0.007). At 5 min after neostigmine administration, the TOFr was higher [87 (74 to 100) vs. 68 (51 to 81)%, respectively; P = 0.002] and the incidence of PORC was lower (50.0 vs. 81.5%, respectively; P = 0.016) in the calcium group than in the control group. There were no differences between the two groups with respect to the TOFr or incidence of PORC at 10 and 20 min after neostigmine administration. CONCLUSION: Calcium chloride coadministered with neostigmine enhanced neuromuscular recovery in the early period of nondepolarising neuromuscular blockade reversal.

Intrathecal morphine for postoperative pain control following robot-assisted prostatectomy: a prospective randomized trial.

PURPOSE: Robot-assisted laparoscopic prostatectomy (RALP) is minimally invasive surgery, but also causes moderate to severe pain during the immediate postoperative period. We evaluated the efficacy and safety of intrathecal morphine (ITM) for postoperative pain control in patients undergoing RALP. METHODS: Thirty patients scheduled for RALP were randomly assigned into one of two groups. In the ITM group (n = 15), postoperative pain was managed using 300 µg intrathecal morphine with intravenous patient-controlled analgesia (IV-PCA). In the IV-PCA group (n = 15), only intravenous patient-controlled analgesia was used. The numerical pain score (NPS; 0 = no pain, 100 = worst pain imaginable), postoperative IV-PCA requirements and opioid-related complications including nausea, vomiting, dizziness, headache and pruritus were compared between the two groups. RESULTS: The NPSs on coughing were 20 (IQR 10-50) in the ITM group and 60 (IQR 40-80) in the IV-PCA group at postoperative 24 h (p = 0.001). The NPSs were significantly lower in the ITM group up to postoperative 24 h. The ITM group showed less morphine consumption at postoperative 24 h in the ITM group than in the IV-PCA group [5 (IQR 3-15) mg vs 17 (IQR 11-24) mg, p = 0.001]. Complications associated with morphine were comparable between the two groups and respiratory depression was not reported in either group. CONCLUSION: Intrathecal morphine provided more satisfactory analgesia without serious complications during the early postoperative period in patients undergoing RALP.

Combined intraoperative paracetamol and preoperative dexamethasone reduces postoperative sore throat: a prospective randomized study.

PURPOSE: Postoperative sore throat (POST) after general anesthesia with endotracheal intubation is a common and undesirable complication. In this study, we evaluated the combined effects of paracetamol and dexamethasone on the prevention of POST in patients after general anesthesia. METHODS: A total of 226 patients scheduled for urologic surgery under general anesthesia were randomly assigned to one of two groups. In the DexaPara group (n = 113), dexamethasone (10 mg) and paracetamol (1000 mg) was infused. In the Dexa group (n = 113), dexamethasone (10 mg) alone was given. POST, hoarseness, and dysphagia were monitored. The postoperative wound pain score and perioperative opioid requirements were compared. In addition, complications related to opioids were compared between the groups. RESULTS: The overall incidence of POST was lower in the DexaPara group than in the Dexa group [42 (37%) vs. 72 (64%), p < 0.001]. The incidence of POST while resting at postoperative 1 and 6 h was lower in the DexaPara group than in the Dexa group (p = 0.008 and p = 0.004, respectively). The incidence of postoperative nausea, vomiting, drowsiness, shivering, and headache was comparable between the groups. CONCLUSIONS: Paracetamol and dexamethasone infusion reduced the incidence of POST without serious complications in patients for urologic surgery under general anesthesia.

Influence of caudal traction of ipsilateral arm on ultrasound image for supraclavicular central venous catheterization.

BACKGROUND: The first step for successful ultrasound (US)-guided subclavian vein (SCV) catheterization using a supraclavicular approach is to obtain a good longitudinal image of SCV for in-plane needle placement. We evaluated the efficacy of caudal traction of ipsilateral arm on the exposure of the SCV. METHODS: We enrolled 20 infants, 20 children, and 20 adults undergoing general anesthesia. After tracheal intubation, US probe was applied as the supraclavicular approach, and the longitudinal US image of SCV was obtained in 3 different ipsilateral arm positions: neutral, caudal traction, and abduction. The length of puncturable SCV, the diameter of SCV, and the available angle for needle insertion in 3 different arm positions were analyzed. RESULTS: In all patients, the length of puncturable SCV and the available angle for needle insertion were significantly increased after caudal traction (35.6% ± 27.1% and 25.0% ± 19.3%, respectively) and decreased after the abduction (36.6% ± 22.9% and 29.5% ± 23.8%, respectively) compared to neutral position. The diameter of SCV was not changed after applying the caudal traction in infants and children. However, in adults, the caudal traction slightly increased the diameter of SCV (P = .012). CONCLUSION: The caudal traction of ipsilateral arm toward to the knee improves the longitudinal US view of SCV for the supraclavicular approach, without reducing its size. Proper caudal traction of the arm might ensure the high success rate with safe needle insertion technique. Abduction should be avoided during US-guided supraclavicular SCV catheterization.

The effect of sevoflurane versus desflurane on postoperative catheter-related bladder discomfort in patients undergoing transurethral excision of a bladder tumour: a randomized controlled trial.

PURPOSE: Catheter-related bladder discomfort (CRBD) due to an indwelling urinary catheter can cause postoperative distress, and the mechanism underlying CRBD is linked to the activation of muscarinic receptors. Inhalation of anesthetic agents, such as sevoflurane and desflurane, has differential inhibitory effects on muscarinic receptors. We aimed to compare the effect of intraoperative sevoflurane vs desflurane inhalation on postoperative CRBD. METHODS: Eighty-nine patients undergoing transurethral resection of a bladder tumour (TURBT) were randomly allocated to two groups. The sevoflurane group (n = 45) and the desflurane group (n = 44) received the respective inhalational agents for maintenance of general anesthesia. The incidence and severity (mild/moderate/severe) of CRBD were assessed at zero, one, six, and 24 hr postoperatively. RESULTS: Catheter-related bladder discomfort during the first 24 hr postoperatively occurred in 34/45 (76%) patients receiving sevoflurane compared with 41/44 (93%) patients receiving desflurane [absolute difference 18%; 95% confidence interval [CI], 2 to 33; P = 0.039]. The differences in the rate of CRBD between the sevoflurane and desflurane groups at zero, one, and six hours postoperatively were 24% (95% CI, 7 to 40; P = 0.012), 33% (95% CI, 15 to 49; P = 0.001), and 26% (95% CI, 6 to 43; P = 0.019), respectively. The incidence of moderate to severe CRBD and the number of patients treated with tramadol for CRBD were comparable between the two groups. CONCLUSIONS: As a maintenance agent of general anesthesia, sevoflurane reduced the incidence of early postoperative CRBD in patients undergoing TURBT when compared with desflurane. The protocol for this clinical trial was registered at ClinicalTrials.gov (NCT02096224).

Comparison of the endotracheal tube cuff pressure between a tapered- versus a cylindrical-shaped cuff after changing from the supine to the lateral flank position.

PURPOSE: Positional change can displace an endotracheal tube (ETT) and change the ETT cuff pressure in a tracheally intubated patient. Endotracheal tubes with different cuff shapes may lead to different cuff pressures after positional change. We hypothesized that the intracuff pressure in the TaperGuard™ ETT with a tapered-shaped cuff would be higher than that in the conventional ETT with a cylindrical-shaped cuff after a change from the supine to the lateral flank position. METHODS: Fifty-eight patients scheduled for open urological procedures in the lateral flank position were randomly allocated to receive either a TaperGuard ETT (group T) or conventional ETT (group C). The ETT cuff pressure was initially set at 20 cm H2O in the supine position and was measured after the change to the lateral flank position. The distance from the ETT tip to the carina was measured in both the supine and the lateral flank positions. RESULTS: Two patients, one from each group, were excluded from the data analysis. The mean (SD) ETT cuff pressure was significantly higher in group T (n = 28) than in group C (n = 28) after the change in position [31 (7) cm H2O vs 25 (4) cm H2O, respectively; mean difference, 6 cm; 95% confidence intervals [CI], 3 to 9; P < 0.001]. The mean (SD) proximal migration of the ETT tip was comparable between the two groups [8 (18) mm vs 4 (14) mm, respectively; P = 0.367]. CONCLUSIONS: After the change from the supine to the lateral flank position, the ETT cuff pressure was significantly higher in the TaperGuard ETT than in the conventional ETT, although the extent of cephalad displacement of the ETT was comparable between the two groups. This trial was registered at Clinicaltrials.gov: NCT02165319.

The effect of intraoperative dexmedetomidine on postoperative catheter-related bladder discomfort in patients undergoing transurethral bladder tumour resection: A double-blind randomised study.

BACKGROUND: Catheter-related bladder discomfort (CRBD) due to an indwelling urinary catheter causes postoperative distress. Dexmedetomidine is used as an anaesthetic adjuvant during general anaesthesia and has an antimuscarinic effect, which may be beneficial for the prevention and treatment of CRBD. OBJECTIVE: To determine the effect of intraoperative dexmedetomidine administration on the incidence of CRBD. DESIGN: A double-blind, placebo-controlled, randomised study. SETTING: A tertiary care teaching hospital. PATIENTS: One-hundred and nine patients undergoing transurethral bladder tumour excision (TURB). INTERVENTIONS: Patients were randomly allocated to two groups: control group (n = 55) received placebo and dexmedetomidine group (n = 54) received intraoperative dexmedetomidine (1 µg kg(-1) loading dose followed by 0.5 µg kg(-1) h(-1) continuous infusion). MAIN OUTCOME MEASURES: The incidence and severity (mild, moderate, severe) of CRBD assessed at 0, 1, 6 and 24 h postoperatively. RESULTS: The incidence of CRBD was significantly higher in the control group at 0 (78 vs. 50%; P = 0.004), 1 (86 vs. 57%; P = 0.002) and 6 h (82 vs. 63%; P = 0.047) postoperatively. The incidence of moderate to severe CRBD was higher in the control group at 0 (38 vs. 11%; P = 0.002) and 1 h (29 vs. 7%; P = 0.006) postoperatively. The number of patients having CRBD treated with tramadol was higher in the control group (24 vs. 12; P = 0.006). The mean end-tidal desflurane concentration during the surgery was higher in the control group (4.5 vs. 3.9%; P = 0.04). The postoperative pain score (numerical rating scale: 0 to 10) was higher in the control group at 0 (4.6 vs. 2.7; P = 0.002), and 1 h (3.8 vs. 2.7; P = 0.041). The number of patients treated with opioids was higher in the control group (21 vs. 8; P = 0.011). CONCLUSION: Intraoperative dexmedetomidine administration decreased the incidence and severity of early postoperative CRBD as well as intraoperative desflurane and postoperative opioid requirements in patients undergoing TURB. TRIAL REGISTRATION IDENTIFIER: NCT01991223 (www.clinicaltrials.gov).

Effect of glycopyrrolate versus atropine coadministered with neostigmine for reversal of rocuronium on postoperative catheter-related bladder discomfort in patients undergoing transurethral resection of bladder tumor: a prospective randomized study.

BACKGROUND: Muscarinic receptors are involved in the mechanism of postoperative catheter-related bladder discomfort (CRBD). Glycopyrrolate and atropine as adjuncts to reversal of neuromuscular blockers have differential inhibitory effects on muscarinic receptors. This study was conducted to compare the effect of glycopyrrolate versus atropine on postoperative CRBD in patients undergoing transurethral resection of a bladder tumor (TURBT). METHODS: Seventy-four patients undergoing TURBT were randomly allocated to receive either glycopyrrolate 10 µg/kg (glycopyrrolate group, n = 37) or atropine 15 µg/kg (atropine group, n = 37) in combination with neostigmine 25 µg/kg at the end of surgery for reversal of neuromuscular blockade. The incidence and severity (mild/moderate/severe) of CRBD were assessed at 0, 1, 6, and 24 h postoperatively. Tramadol 50-100 mg was administered intravenously if the patients complained of moderate or severe CRBD. RESULTS: The incidence of CRBD was significantly lower in the glycopyrrolate group than in the atropine group at 0 h (65 % vs. 89 %, p = 0.025) and 1 h (54 % vs. 89 %, p = 0.002) postoperatively. The severity of postoperative CRBD was less severe in the glycopyrrolate group than in the atropine group at 0 h (p = 0.013) and 1 h (p = 0.006). Fewer patients required tramadol in the glycopyrrolate group than in the atropine group (3 % vs. 12 %, p = 0.024). CONCLUSIONS: Glycopyrrolate as an adjunct to reversal of neuromuscular blockers decreased the incidence of early postoperative CRBD and postoperative tramadol requirements in patients undergoing TURBT when compared to atropine.

A peroxisome proliferator-activated receptor gamma agonist attenuates neurological deficits following spinal cord ischemia in rats.

OBJECTIVE: Neuroprotective effects of the peroxisome proliferator-activated receptor gamma (PPARγ) agonist in cerebral ischemia have been reported, but the effect of a PPARγ agonist on spinal cord ischemia has not been investigated. The objective of this study was to investigate the effect of a PPARγ agonist on spinal cord ischemia. Pioglitazone, a PPARγ agonist, was administered in a rat model of spinal cord ischemia, and the extent of neurological damage and histological alterations were assessed. METHODS: Forty-five rats were randomly enrolled into one of the three groups: (1) pioglitazone group (group PIO): rats were treated with pioglitazone 24 hours before ischemia; (2) control group (group C): rats were treated with the same volume of saline 24 hours before ischemia; and (3) sham group (group sham): rats were treated with the same volume of saline 24 hours before the sham surgery. Spinal cord ischemia was induced using a balloon-tipped catheter placed on the proximal descending aorta. Neurologic function was assessed using the motor deficit index (0 = normal, 6 = complete paralysis) during the 48 hours after reperfusion. Histological and biochemical evaluations were then performed. RESULTS: Compared with group C, group PIO presented with lower motor deficit index 48 hours after reperfusion (5.0 [4.0-6.0] vs 3.0 [2.0-3.0]; group C vs group PIO, respectively; P < .001). Group PIO presented with a higher number of normal motor neurons (10.7 [8.1-11.9] vs 14.7 [14.0-15.3]; group C vs group PIO, respectively; P = .009) and a smaller area of infarcts (48.4% [46.3%-54.0%] vs 16.8% [11.5%-18.3%]; group C vs group PIO, respectively; P = .009) when compared with group C. The degree of inflammatory reactions, assessed by microglia activities, was significantly reduced in group PIO. Oxidative stress level, assessed using malonydialdehyde assay, was significantly reduced in group PIO relative to group C (192.21% [173.5%-206.4%] of sham vs 141.1% [131.7%-152.1%] of sham; group C vs group PIO, respectively; P = .007). The sham group exhibited no abnormality upon neurological or histological examination. CONCLUSIONS: PPARγ agonist pioglitazone pretreatment significantly reduces infarct volume and attenuates neurological deficits following spinal cord ischemia. The possible mechanism of neuroprotection by PPARγ agonist may involve modulation of inflammatory reaction and oxidative stress.

Albumin Leakage Level during Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy Is Associated with Major Complications.

The clinical consequences of perioperative albumin extravasation accompanying major abdominal surgery remain underexplored. We retrospectively reviewed the data of patients who underwent cytoreductive surgery (CRS) and hyperthermic intraoperative peritoneal chemotherapy (HIPEC). Parameters of albumin kinetics, including serum albumin concentration decrease (∆Alb) and extravasated albumin level (Albshift), were assessed from surgery until postoperative day (POD) 3. Logistic regression analysis identified factors associated with major complications. The association of albumin kinetics with major complications was evaluated using receiver operating characteristic (ROC) curve analysis. Serum albumin levels decreased during surgery and subsequently increased. Of the 121 analyzed patients, 25 (21%) developed major complications. The ∆Alb and Albshift during surgery and on POD 3 were greater in patients who developed major complications than in those who did not (12 ± 12 vs. 6 ± 14, p = 0.032, and 127.5 (71.9) vs. 48.5 (44.9), p < 0.001, respectively). Perioperative ∆Alb and Albshift were associated with major complications. The areas under the ROC curve of Albshift during the 3 days post-surgery and Albshift on POD 3 were 0.843 and 0.910, respectively. Albshift during the 3 days post-surgery and Albshift on POD 3 were correlated with complications (p < 0.05). In conclusion, perioperative albumin loss was associated with major complications in patients undergoing CRS and HIPEC. Albshift was associated with serious complications.

Quantitative Analysis of the Effect of Neuromuscular Blockade on Motor-Evoked Potentials in Patients Undergoing Brain Tumor Removal Surgery: A Prospective, Single-Arm, Open-Label Observational Study.

Background: We aimed to elucidate the quantitative relationship between the neuromuscular blockade depth and intraoperative motor-evoked potential amplitudes. Methods: This prospective, single-arm, open-label, observational study was conducted at a single university hospital in Seoul, Korea, and included 100 adult patients aged ≥19 years undergoing brain tumor removal surgery under general anesthesia. We measured the neuromuscular blockade degree and motor-evoked potential amplitude in the deltoid, abductor pollicis brevis, tibialis anterior, and abductor hallucis muscles until dural opening. Results: The pharmacokinetic-pharmacodynamic model revealed the exposure-response relationship between the rocuronium effect-site concentration and motor-evoked potential amplitudes. The mean motor-evoked potential amplitudes decreased proportionally with increasing neuromuscular blockade depth. As the mean amplitude increased, the coefficient of variation decreased bi-exponentially. The critical ratio of the first evoked response to the train-of-four stimulation (T1)/control response (Tc) thresholds beyond which the coefficient of variation exhibited minimal change were found to be 0.63, 0.65, 0.68, and 0.63 for the deltoid, abductor pollicis brevis, tibialis anterior, and abductor hallucis muscles, respectively. Conclusions: Our results reveal that the motor-evoked potential amplitude exhibits deterioration proportional to the degree of neuromuscular blockade. In light of the observed bi-exponential decline of the coefficient of variation with the motor-evoked potential amplitude, we recommend maintaining a T1/Tc ratio higher than 0.6 for partial neuromuscular blockade.