Experience Verification of 63 Cases of Liver Transplantation Anesthesia Management

Background: We reviewed the intraoperative management of previous liver transplantation (LT) cases to identify an optimal anesthetic method, which may affect patient outcomes and lead to faster postoperative recovery for future recipients. Methods: This single-center retrospective study reviewed 63 patients who underwent LT, including 51 living donor LT (LDLT), seven deceased donor LT (DDLT), and five simultaneous liver-kidney transplantation patients. We examined the patients’ backgrounds, intraoperative management (anesthetic method, water balance, and catecholamine dosage), and postoperative courses (hospitalization period, length of intensive care unit stay, renal function). Results: All patients received general anesthesia using inhalational anesthetics, either sevoflurane or desflurane, and both drugs were administered similarly. Rocuronium was administered at its usual dose despite liver failure. All patients undergoing preoperative dialysis due to acute kidney injury were successfully withdrawn from dialysis after surgery. The albumin infusion volume was 32% of the total infusion and transfusion volume. The five-year survival rate was 88% and graft failure occurred in one case. Conclusion: The anesthetic management of LT is currently conducted empirically in our institution, and we could not identify an optimal anesthetic method. However, we drew some conclusions. First, the use of human atrial natriuretic peptide as a drug infusion and appropriate transfusion management was expected to restore renal function. Second, the infusion volume of albumin was high. Third, the usual dose of rocuronium was required because excessive bleeding may cause unstable plasma drug concentration. Our results will be useful in future multi-institutional studies or meta-analyses and further improving the outcomes of future transplant recipients.

AnesthesiaGUIDE: a MATLAB tool to control the anesthesia

The goals of this paper are: (a) to investigate adaptive and fractional-order adaptive control algorithms for an automatic anesthesia process, using a closed-loop system, and (b) to develop an easy-to-use tool for MATLAB/Simulink to facilitate simulations for users with less knowledge about anesthesia and adaptive control. A model reference adaptive control structure was chosen for the entire system. First of all, to control the patient’s state during the surgery process, the patient mathematical model is useful, or even required for simulation studies. The pharmacokinetic/pharmacodynamics (PK/PD) model was determined using MATLAB’s SimBiology tool, starting from a previously available block diagram, and validated through simulation. Then, to achieve the desired control performances, two controllers are designed: a PI adaptive controller and a PIλ (PI-fractional) adaptive controller, using the MIT algorithm. The time response during anesthetic drug infusion for each patient can be plotted with the AnesthesiaGUIDE tool, which is also designed in MATLAB/Simulink. The tool was tested on data from 12 patients, subjected to general anesthesia, with successful results. Through this tool, the article provides a good opportunity for any user to experience with adaptive control for the anesthesia process.

298 Domiciliary periodic Levosimendan infusions in advanced heart failure: a single centre experience

Aims There are several studies that describes a possible use of periodical infusions of Levosimendan in patients with advance heart failure (AHF). In these studies, Levosimendan was administered in ambulatory settings (LevoRep, LION-HEART) or during 24 h of hospital stay (LAICA) and for a maximum of 12 months. Currently there is no strong evidence about the feasibility and safety of performing the infusions in an out of hospital setting. Aim of our study was to analyse the feasibility and safety of periodical Levosimendan infusions in AHF patients, in an out of hospital setting for palliative use. Methods and results Aretrospective study was conducted from June 2016 to September 2021 on AHF patients, followed by our centre for periodic infusion of Levosimendan. All patients were previously implanted with an ICD, were ineligible for heart transplant or for ventricular assist devices. All patients on each cycle underwent a cardiological evaluation, a blood sample (complete blood count, biochemical profile, coagulation profile, and NTproBNP), and Levosimendan was administrated with a wearable infusion pump (CADD-Legacy®; Smiths Medical). The patient went home and came back the day after, to return the pump and for reassessment. We collected data on the different infusion regimen, adapted for every patient, and on adverse events during infusions. We enrolled 11 patients with AHF, 9 (82%) of which of ischaemic origin, 2 (18%) were female, median age 72 years (IQR: 64–75), 10 with NYHA class III, 1 with a NYHA class IV, for a total of 231 infusions, with a median Follow-up of 459 days (IQR 132; 783). A total dose of 6.25 mg was administered at 0.05 μg/kg/min in 24 h. In five patients the infusion was of 12.5 mg at 0.1 μg/kg/min rate in 24 h and in other three patients at 0.05 μg/kg/min in 48 h. The median interval between administrations was 21 days (IQR: 14–24.5). Mild adverse events (i.e. that did not contraindicate successive cycles) were 7 on 231 infusions (3.0%): symptomatic hypotension (four cases, 1.7%), loss of consciousness (two cases 0.9%), bleeding for vein access misplacement (one case, 0.4%). No serious adverse event such as sustained or malignant arrhythmia, allergic reaction, or need for hospital admission were recorded. Conclusions The administration of Levosimendan at home with a wearable iv pump is safe and well tolerated. This practice allows to reduce infusion costs of day hospital regime and to lengthen the time available for drug infusion, thus reducing the events caused by a too rapid infusion.

Ropivacaine: An Unusual Cause of Neuroleptic Malignant-Like Syndrome

Ropivacaine is commonly used for post-operative pain management. We describe a case of neuroleptic malignant-like syndrome in a woman administered ropivacaine delivered using a drug infusion balloon. The presenting symptoms were confusion, agitation and fever. Blood analysis showed elevated C-reactive protein, leucocytosis and increased creatine phosphokinase. As intoxication was suspected, ropivacaine was suspended and the patient gradually improved. Possible leakage of ropivacaine into the intrathecal space may have resulted in central nervous system toxicity.

Comparative Study of Clevidipine to Nicardipine for Perioperative Hypertension in Patients Undergoing Cardiac Surgery

Objective The primary objective of this study was to compare the efficacy of clevidipine to nicardipine in the treatment of perioperative acute hypertension in patients undergoing cardiac surgery. Methods This was a single-center retrospective study which included patients who received either clevidipine or nicardipine. Patients were followed for the duration of study drug infusion or for a maximum of 48 hours. Outcomes assessed included the percent of time spent within patient specific goal blood pressure, incidence of hypertensive events per patient, safety outcomes, and cost of medication treatment. Results There were 201 cardiac surgeries performed between August 2018–January 2019 and July 2019–February 2020. Sixty-seven patients met our inclusion criteria of receiving either clevidipine (n = 29) or nicardipine (n = 38). The median percent of time spent within goal blood pressure range for clevidipine was 55.2% compared to 36.4% for nicardipine treatment ( P = .036). The median number of hypertensive episodes per patient was 3 for clevidipine and 2 for nicardipine ( P = .211). There were no identified differences in safety outcomes such as hypotension, vasopressor use, serum creatinine elevation, tachycardia, and atrial fibrillation. The median cost of treatment required for the observed 48-hour period with clevidipine was $128.58 compared to $55.74 for nicardipine ( P < .001). Conclusion Our findings suggest that patients undergoing cardiac surgery on clevidipine had better perioperative blood pressure control compared to nicardipine, with a negligible increase in cost, and no observed difference in safety.

The β3 Adrenergic Receptor Antagonist L-748,337 Attenuates Dobutamine-Induced Cardiac Inefficiency While Preserving Inotropy in Anesthetized Pigs

Excessive myocardial oxygen consumption (MVO2) is considered a limitation for catecholamines, termed oxygen cost of contractility. We hypothesize that increased MVO2 induced by dobutamine is not directly related to contractility but linked to intermediary myocardial metabolism. Furthermore, we hypothesize that selective β3 adrenergic receptor (β3AR) antagonism using L-748,337 prevents this. In an open-chest pig model, using general anesthesia, we assessed cardiac energetics, hemodynamics and arterial metabolic substrate levels at baseline, ½ hour and 6 hours after onset of drug infusion. Cardiac efficiency was assessed by relating MVO2 to left ventricular work (PVA; pressure–volume area). Three groups received dobutamine (5 μg/kg/min), dobutamine + L-748,337 (bolus 50 μg/kg), or saline for time-matched controls. Cardiac efficiency was impaired over time with dobutamine infusion, displayed by persistently increased unloaded MVO2 from ½ hour and 47% increase in the slope of the PVA–MVO2 relation after 6 hours. Contractility increased immediately with dobutamine infusion ( dP/ dt max; 1636 ± 478 vs 2888 ± 818 mmHg/s, P < 0.05) and persisted throughout the protocol (2864 ± 1055 mmHg/s, P < 0.05). Arterial free fatty acid increased gradually (0.22 ± 0.13 vs 0.39 ± 0.30 mM, P < 0.05) with peak levels after 6 hours (1.1 ± 0.4 mM, P < 0.05). By combining dobutamine with L-748,337 the progressive impairment in cardiac efficiency was attenuated. Interestingly, this combined treatment effect occurred despite similar alterations in cardiac inotropy and substrate supply. We conclude that the extent of cardiac inefficiency following adrenergic stimulation is dependent on the duration of drug infusion, and β3AR blockade may attenuate this effect.

Effects of circadian rhythm on Narcotrend index and target-controlled infusion concentration of propofol anesthesia

Background The effects of circadian rhythms on drug metabolism and efficacy are being increasingly recognized. However, the extent to which they affect general anesthesia remains unclear. This study aims to investigate the effects of circadian rhythms on anesthetic depth and the concentrations of propofol target-controlled infusion (TCI). Methods Sixty patients undergoing laparoscopic surgeries were sequentially assigned to four groups. Group ND (n = 15): Propofol TCI with Narcotrend monitor during the day (8:00–18:00), Group NN (n = 15): Propofol TCI with Narcotrend monitor during the night (22:00–5:00), Group CLTD (n = 15): Propofol closed-loop TCI guided by bispectral index (BIS) during the day (8:00–18:00), Group CLTN (n = 15): Propofol closed-loop TCI guided by BIS during the night (22:00–5:00). The Narcotrend index, mean arterial pressure (MAP) and heart rate (HR) were compared between group ND and NN at 7 time points, from 5 min before induction to the end of operation. The propofol TCI concentrations, MAP and HR were compared between group CLTD and CLTN at 7 time points, from 5 min after induction to the end of operation. Results The Narcotrend index, MAP, and HR in group NN were lower than those in group ND from the beginning of mechanical ventilation to the end of operation (p < 0.05). The propofol TCI concentrations in group CLTN were lower than those in group CLTD from the beginning of operation to the end of operation (p < 0.05). Conclusion Circadian rhythms have a significant effect on the depth of anesthesia and drug infusion concentrations during propofol TCI. When using general anesthesia during night surgery, the propofol infusion concentration should be appropriately reduced compared to surgery during the day. Trial registration The present study was registered on the ClinicalTrials.gov website (NCT02440269) and approved by the Medical Ethics Committee of Southwest Hospital of Third Military Medical University (ethics lot number: 2016 Research No. 93). All patients provided informed written consent to participate in the study.