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Veterinary Anaesthesia and Analgesia Nov 2017To examine the accuracy of plethysmography variability index (PVI) as a noninvasive indicator of fluid responsiveness in hypovolaemic dogs.
Plethysmography variability index for prediction of fluid responsiveness during graded haemorrhage and transfusion in sevoflurane-anaesthetized mechanically ventilated dogs.
OBJECTIVE
To examine the accuracy of plethysmography variability index (PVI) as a noninvasive indicator of fluid responsiveness in hypovolaemic dogs.
STUDY DESIGN
Prospective experimental study.
ANIMALS
Six adult healthy sevoflurane-anaesthetized Beagle dogs.
METHODS
Dogs were anaesthetized with 1.3-fold their individual minimum alveolar concentration of sevoflurane. The lungs were mechanically ventilated after neuromuscular blockade with vecuronium bromide. Cardiopulmonary variables including mean arterial blood pressure (MAP), central venous pressure (CVP), transpulmonary thermodilution cardiac output (TPTDCO), stroke volume (SV), perfusion index (PI), pulse pressure variation (PPV), stroke volume variation (SVV) and PVI were determined during six stages of graded venous blood withdrawal (5 mL kg increments) and six stages of graded blood infusion (5 mL kg increments). The cardiopulmonary variables were analysed using paired t test or Wilcoxon signed rank test. Correlations between PPV and SVV or PVI were analysed by linear regression. The accuracy of PPV, SVV and PVI for predicting fluid responsiveness was examined by using receiver operating characteristic curve analysis. A value of p < 0.05 was considered statistically significant.
RESULTS
Blood withdrawal resulted in significant increases in PPV and PVI and decreases in MAP, CVP, TPTDCO, SV and PI. Blood infusion resulted in significant increases in MAP, CVP, TPTDCO, SV and PI and decreases in PPV and PVI. PPV and PVI showed a relevant correlation (p < 0.001, r = 0.62) and threshold values of PPV ≥ 16% (sensitivity 71%, specificity 82%) and PVI ≥ 12% (sensitivity 78%, specificity 72%) for identifying fluid responsiveness. SVV did not change.
CONCLUSIONS AND CLINICAL RELEVANCE
Noninvasive measurement of PVI predicted fluid responsiveness with moderate accuracy equal to PPV in sevoflurane-anaesthetized mechanically ventilated dogs. Provisional threshold values for identification of fluid responsiveness were PPV ≥ 16% and PVI ≥ 12%. Clinical trials are needed to confirm these threshold values in dogs.
Topics: Anesthetics, Inhalation; Animals; Blood Pressure; Blood Transfusion; Cardiac Output; Dog Diseases; Dogs; Female; Fluid Therapy; Hemorrhage; Male; Methyl Ethers; Plethysmography; Respiration, Artificial; Sevoflurane; Treatment Outcome
PubMed: 29113716
DOI: 10.1016/j.vaa.2017.07.007 -
Indian Journal of Anaesthesia Mar 2015Obese patients are more vulnerable to residual neuromuscular block (NMB) and its associated complications in the post-operative period. This study was carried out to...
BACKGROUND AND AIMS
Obese patients are more vulnerable to residual neuromuscular block (NMB) and its associated complications in the post-operative period. This study was carried out to compare neostigmine induced reversal of vecuronium in normal weight, overweight and obese female patients, objectively using neuromuscular (NM) monitoring.
METHODS
Twenty female patients each belonging to normal weight, overweight and obese, based on body mass index, requiring general anaesthesia were recruited for this prospective cross sectional study. NMB was induced with vecuronium (0.1 mg/kg) dose based on patient's real body weight (RBW) and monitored using acceleromyographic train of four (TOF). All patients received neostigmine 40 μg/kg and glycopyrrolate 10 μg/kg at 25% of spontaneous recovery of first twitch height (T1) of TOF (DUR 25%) and were allowed to recover to TOF ratio of 0.9. Statistical analysis was done using analysis of variance test.
RESULTS
Recovery of TOF ratio to 0.5 was comparable in all three groups. Recovery of TOF ratio to 0.7 was delayed in obese (9.82 ± 3.21 min) compared with normal weight group (7.50 ± 2.52 min). Recovery of TOF to 0.9 was significantly delayed in both overweight (12.18 ± 4.29 min) and obese patients (13.78 ± 4.30 min). DUR 25% was significantly longer in overweight (mean, standard deviation [range]; 30.10 [19-40 min]) and obese (28.8 [12-45 min]) compared with normal weight patients (22.75 [16-30 min]).
CONCLUSION
In overweight and obese patients, when vecuronium induction dose is based on RBW, neostigmine induced recovery of NMB is delayed in late phases (TOF 0.7-0.9), which may result in vulnerability for associated complications of incomplete recovery. Ensuring safe recovery thus requires objective NM monitoring.
PubMed: 25838588
DOI: 10.4103/0019-5049.153038 -
Antioxidants (Basel, Switzerland) Jan 2020Hypothermia enhances outcomes of patients after resuscitation after cardiac arrest (CA). However, the underlying mechanism is not fully understood. In this study, we...
Hypothermia enhances outcomes of patients after resuscitation after cardiac arrest (CA). However, the underlying mechanism is not fully understood. In this study, we investigated effects of hypothermic therapy on neuronal damage/death, microglial activation, and changes of endogenous antioxidants in the anterior horn in the lumbar spinal cord in a rat model of asphyxial CA (ACA). A total of 77 adult male Sprague-Dawley rats were randomized into five groups: normal, sham ACA plus (+) normothermia, ACA + normothermia, sham ACA + hypothermia, and ACA + hypothermia. ACA was induced for 5 min by injecting vecuronium bromide. Therapeutic hypothermia was applied after return of spontaneous circulation (ROSC) via rapid cooling with isopropyl alcohol wipes, which was maintained at 33 ± 0.5 °C for 4 h. Normothermia groups were maintained at 37 ± 0.2 °C for 4 h. Neuronal protection, microgliosis, oxidative stress, and changes of endogenous antioxidants were evaluated at 12 h, 1 day, and 2 days after ROSC following ACA. ACA resulted in neuronal damage from 12 h after ROSC and evoked obvious degeneration/loss of spinal neurons in the ventral horn at 1 day after ACA, showing motor deficit of the hind limb. In addition, ACA resulted in a gradual increase in microgliosis with time after ACA. Therapeutic hypothermia significantly reduced neuronal loss and attenuated hind limb dysfunction, showing that hypothermia significantly attenuated microgliosis. Furthermore, hypothermia significantly suppressed ACA-induced increases of superoxide anion production and 8-hydroxyguanine expression, and significantly increased superoxide dismutase 1 (SOD1), SOD2, catalase, and glutathione peroxidase. Taken together, hypothermic therapy was found to have a substantial impact on changes in ACA-induced microglia activation, oxidative stress factors, and antioxidant enzymes in the ventral horn of the lumbar spinal cord, which closely correlate with neuronal protection and neurological performance after ACA.
PubMed: 31906329
DOI: 10.3390/antiox9010038 -
Turkish Journal of Medical Sciences Nov 2017Background/aim: Myocardial protection is an important factor of open heart surgery and biological biomarkers (lactate, CKMB, cardiac troponin I, and pyruvate) are used...
Background/aim: Myocardial protection is an important factor of open heart surgery and biological biomarkers (lactate, CKMB, cardiac troponin I, and pyruvate) are used to assess myocardial damage. This study compares the effects of dexmedetomidine and remifentanil on myocardial protection during coronary artery bypass grafting (CABG) surgery. Materials and methods: Patients scheduled for elective CABG surgery (n = 60) were included in this study. Anesthesia induction was introduced with propofol, fentanyl, and vecuronium bromide. Anesthesia was maintained with remifentanil infusion and sevoflurane in the remifentanil group (Group R) and with dexmedetomidine infusion and sevoflurane in the dexmedetomidine group (Group D). Blood samples for biochemical markers were taken from the coronary sinus catheter before cardiopulmonary bypass (T1), 20 min after aortic cross-clamping (T2), 20 min after removal of the aortic cross-clamping (T3), and 10 min after separation from cardiopulmonary bypass (T4).Results: Demographic data were similar between the groups. Lactate level at the T2 period and CKMB levels during the study period were lower in Group D than in Group R. In both groups, all values except pyruvate significantly increased over time. Conclusion: The dexmedetomidine-sevoflurane combination may improve the cardioprotective effect in comparison with remifentanil-sevoflurane in CABG surgery.
PubMed: 29151310
DOI: 10.3906/sag-1612-130 -
Journal of Anesthesia Dec 2016Sevoflurane is known to prolong the QT interval. This study aimed to determine the effect of the interaction between intravenous anesthetics and sevoflurane on the QT... (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
Sevoflurane is known to prolong the QT interval. This study aimed to determine the effect of the interaction between intravenous anesthetics and sevoflurane on the QT interval.
METHODS
The study included 48 patients who underwent lumbar spine surgery. Patients received 3 μg/kg fentanyl and were then randomly allocated to either Group T, in which they received 5 mg/kg thiamylal, or Group P, in which they received 1.5 mg/kg propofol, at 2 min after administration of fentanyl injection for anesthetic induction. Vecuronium (1.5 mg/kg) and sevoflurane (3 % inhaled concentration) were administered immediately after loss of consciousness and tracheal intubation was performed 3 min after vecuronium injection. Heart rate (HR), mean arterial pressure (MAP), bispectral index score (BIS), and the heart rate-corrected QT (QTc) interval on a 12-lead electrocardiogram were recorded immediately before fentanyl administration (T1), 2 min after fentanyl injection (T2), immediately before intubation (T3), and 2 min after intubation (T4).
RESULTS
There were no significant differences between the two groups in baseline patient characteristics. BIS and MAP significantly decreased after anesthesia induction in both groups. At T3, MAP in Group T was higher than in Group P, while HR had reduced in both groups. The QTc interval was prolonged after anesthesia induction in Group T, but did not change at any time point in Group P. The QTc interval after anesthesia induction in Group T was longer than in Group P.
CONCLUSION
We concluded that an injection of propofol could counteract QTc interval prolongation associated with sevoflurane anesthesia induction.
Topics: Adult; Aged; Anesthetics, Intravenous; Arterial Pressure; Electrocardiography; Female; Fentanyl; Heart Rate; Humans; Intubation, Intratracheal; Male; Methyl Ethers; Middle Aged; Propofol; Sevoflurane; Vecuronium Bromide
PubMed: 27655646
DOI: 10.1007/s00540-016-2252-8 -
ELife Apr 2015Using the visual system as a model, we recently showed that the efficient coding principle accounted for the allocation of computational resources in central sensory...
Using the visual system as a model, we recently showed that the efficient coding principle accounted for the allocation of computational resources in central sensory processing: when sampling an image is the main limitation, resources are devoted to compute the statistical features that are the most variable, and therefore the most informative (eLife 2014;3:e03722. DOI: 10.7554/eLife.03722 Hermundstad et al., 2014). Building on these results, we use single-unit recordings in the macaque monkey to determine where these computations--sensitivity to specific multipoint correlations--occur. We find that these computations take place in visual area V2, primarily in its supragranular layers. The demonstration that V2 neurons are sensitive to the multipoint correlations that are informative about natural images provides a common computational underpinning for diverse but well-recognized aspects of neural processing in V2, including its sensitivity to corners, junctions, illusory contours, figure/ground, and 'naturalness.'
Topics: Action Potentials; Anesthetics, Intravenous; Animals; Brain Mapping; Electrodes, Implanted; Image Processing, Computer-Assisted; Macaca mulatta; Neuromuscular Nondepolarizing Agents; Neurons; Pattern Recognition, Visual; Photic Stimulation; Propofol; Single-Cell Analysis; Vecuronium Bromide; Visual Cortex
PubMed: 25915622
DOI: 10.7554/eLife.06604 -
Neonatology 2015The lower margin amplitude (LMA) of the amplitude-integrated electroencephalogram (aEEG) is suppressed in neonates during deep sedation, a feature that is attributed to...
BACKGROUND
The lower margin amplitude (LMA) of the amplitude-integrated electroencephalogram (aEEG) is suppressed in neonates during deep sedation, a feature that is attributed to the bispectral index (BIS) in adults.
OBJECTIVE
We compare the BIS and the LMA of the aEEG in neonates.
METHODS
Thirty neurologically healthy neonates between 37 and 44 weeks postmenstrual age were included in this study. Twenty patients received sedoanalgesic therapy for various reasons. BIS and aEEG recordings were performed simultaneously. The digital data were imported in the numerical software environment Matlab®. The LMA of the aEEG was computed on a 1-min time scale and synchronized with the BIS data. The correlation between the time-dependent variables BIS and LMA was estimated using the Spearman rank correlation index.
RESULTS
The median correlation between BIS and LMA was 0.3. Inclusion of recordings of high signal quality only into analysis improved the median correlation index to 0.6.
CONCLUSIONS
We found a light-to-moderate correlation between BIS and LMA in our study cohort and a good correlation in the subgroup with high signal quality.
Topics: Analgesics, Opioid; Brain Waves; Deep Sedation; Electroencephalography; Female; Fentanyl; Humans; Hypnotics and Sedatives; Infant, Newborn; Infant, Newborn, Diseases; Male; Midazolam; Morphine; Neuromuscular Blocking Agents; Neurophysiological Monitoring; Vecuronium Bromide
PubMed: 25323947
DOI: 10.1159/000365277 -
European Journal of Anaesthesiology May 2016Intraoperative anaphylaxis to neuromuscular blocking agents (NMBAs) is a rare event that is unpredictable and potentially life threatening. Most of the previous reports... (Observational Study)
Observational Study
BACKGROUND
Intraoperative anaphylaxis to neuromuscular blocking agents (NMBAs) is a rare event that is unpredictable and potentially life threatening. Most of the previous reports on such intraoperative anaphylaxis used market share surveys or self-reported data to estimate the incidence.
OBJECTIVE
To determine the incidences of intraoperative anaphylaxis to NMBAs using electronic medical records.
DESIGN
A retrospective observational study.
SETTING
Two tertiary hospitals in South Korea.
PATIENTS
This study involved patients exposed to NMBAs during anaesthesia between 1 January 2005 and 31 May 2014. Nineteen episodes were deemed to be intraoperative anaphylaxis to NMBAs.
MAIN OUTCOME MEASURES
We calculated the incidences of intraoperative anaphylaxis to NMBAs. Exposure to the agents was determined from intraoperative records maintained in an electronic medical recording system. An anaphylactic reaction was determined from both clinical signs and the results of skin tests.
RESULTS
Over 9 years, 729 429 patients were exposed to NMBA, the most frequently used being rocuronium [425 047 (58.3%)] and vecuronium [274 801 (37.7%)]. The overall incidence of intraoperative anaphylaxis was 2.6 per 100 000 (19 cases), and was higher with rocuronium (16 cases, 3.8 per 100 000) than with vecuronium (two cases, 0.7 cases per 100 000), P = 0.014. Comparing the first 3 years with the last 6 years, the incidence of intraoperative rocuronium anaphylaxis appeared to increase 1.4-fold (P = 0.006).
CONCLUSION
Among commonly used NMBAs, rocuronium appears to have the highest incidence of anaphylaxis. Our findings suggest that future prospective investigation for NMBA-induced anaphylaxis should use internationally agreed skin test protocols.
Topics: Adolescent; Adult; Aged; Anaphylaxis; Androstanols; Electronic Health Records; Female; Humans; Incidence; Intraoperative Care; Male; Middle Aged; Neuromuscular Blockade; Neuromuscular Nondepolarizing Agents; Republic of Korea; Retrospective Studies; Risk Factors; Rocuronium; Skin Tests; Tertiary Care Centers; Time Factors; Vecuronium Bromide
PubMed: 26575006
DOI: 10.1097/EJA.0000000000000373 -
Anesthesiology Sep 2017Rocuronium-induced neuromuscular block that spontaneously recovered to a train-of-four count of four can be reversed with sugammadex 0.5 or 1.0 mg/kg. We investigated... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Rocuronium-induced neuromuscular block that spontaneously recovered to a train-of-four count of four can be reversed with sugammadex 0.5 or 1.0 mg/kg. We investigated whether these doses of sugammadex can also reverse vecuronium at a similar level of block.
METHODS
Sixty-five patients were randomly assigned, and 64 were analyzed in this controlled, superiority study. Participants received general anesthesia with propofol, sevoflurane, fentanyl, and vecuronium. Measurement of neuromuscular function was performed with acceleromyography (TOF-Watch-SX, Organon Teknika B.V., The Netherlands ). Once the block recovered spontaneously to four twitches in response to train-of-four stimulation, patients were randomly assigned to receive sugammadex 0.5, 1.0, or 2.0 mg/kg; neostigmine 0.05 mg/kg; or placebo. Time from study drug injection to normalized train-of-four ratio 0.9 and the incidence of incomplete reversal within 30 min were the primary outcome variables. Secondary outcome was the incidence of reparalysis (normalized train-of-four ratio less than 0.9).
RESULTS
Sugammadex, in doses of 1.0 and 2.0 mg/kg, reversed a threshold train-of-four count of four to normalized train-of-four ratio of 0.9 or higher in all patients in 4.4 ± 2.3 min (mean ± SD) and 2.6 ± 1.6 min, respectively. Sugammadex 0.5 mg/kg reversed the block in 6.8 ± 4.1 min in 70% of patients (P < 0.0001 vs. 1.0 and 2.0 mg/kg), whereas neostigmine produced reversal in 11.3 ± 9.7 min in 77% of patients (P > 0.05 vs. sugammadex 0.5 mg/kg). The overall frequency of reparalysis was 18.7%, but this incidence varied from group to group.
CONCLUSIONS
Sugammadex 1.0 mg/kg, unlike 0.5 mg/kg, properly reversed a threshold train-of-four count of four vecuronium-induced block but did not prevent reparalysis.
Topics: Adult; Dose-Response Relationship, Drug; Female; Humans; Male; Middle Aged; Neuromuscular Blockade; Neuromuscular Junction; Neuromuscular Nondepolarizing Agents; Sugammadex; Vecuronium Bromide; gamma-Cyclodextrins
PubMed: 28640017
DOI: 10.1097/ALN.0000000000001744 -
Journal of Clinical Monitoring and... Apr 2017Previous studies have shown that sugammadex decreases the anesthetic depth when administered to reverse the neuromuscular blockade produced by rocuronium/vecuronium. The... (Randomized Controlled Trial)
Randomized Controlled Trial
Previous studies have shown that sugammadex decreases the anesthetic depth when administered to reverse the neuromuscular blockade produced by rocuronium/vecuronium. The aim of the present study was to investigate the effect of sugammadex alone on anesthetic depth and hemodynamics. Sixty patients scheduled for abdominal surgery participated in the study. Anesthesia was induced with thiopental/fentanyl and maintained with NO/oxygen and sevoflurane concentrations adjusted to maintain Entropy and Bispectral Index (BIS) values between 40 and 50. Cis-atracurium 0.2 mg/kg was administered for neuromuscular blockade which was monitored with a TOF-Watch SX acceleromyograph. State entropy (SE), response entropy (RE), Bispectral Index (BIS), systolic (SAP) and diastolic blood pressure (DAP), heart rate (HR), SpO, end-tidal CO and sevoflurane concentrations were recorded every 3 min intraoperatively. Sugammadex 2 mg/kg (Group-2), 4 mg/kg (Group-4) or 16 mg/kg (Group-16) was given intravenously when a count of two responses of the train-of-four (TOF) or a post-tetanic count (PTC) 1-3 appeared or when no response at all (PTC = 0) was observed, respectively. The overall SE values, thus the primary outcome of the study, were 44 ± 11, 43 ± 10 and 43 ± 11 for Group-2, Group-4 and Group-16, respectively (p = 0.812). Also, the secondary endpoints, namely RE, BIS, SAP and DAP, HR and SpO did not differ between the three groups. Comparisons between Group-2 versus Group-4, Group-2 versus Group-16 and Group-4 versus Group-16 showed no differences (p > 0.05) for all the studied variables. Sugammadex alone at low, medium or high clinical doses has no effect on anesthetic depth as assessed by Entropy and BIS or on hemodynamics.
Topics: Adult; Aged; Aged, 80 and over; Androstanols; Anesthesia; Anesthesia Recovery Period; Atracurium; Double-Blind Method; Drug Administration Schedule; Electrocardiography; Entropy; Female; Hemodynamics; Humans; Male; Methyl Ethers; Middle Aged; Monitoring, Intraoperative; Neuromuscular Blockade; Neuromuscular Nondepolarizing Agents; Oxygen; Rocuronium; Sevoflurane; Sugammadex; Vecuronium Bromide; gamma-Cyclodextrins
PubMed: 26894591
DOI: 10.1007/s10877-016-9844-6