Evaluation of the three different doses of cisatracurium during general anaesthesia: A prospective randomized study.

Background and Aims: The present study was conducted to determine the optimal dose of cisatracurium for intubating conditions and onset and offset of neuromuscular blockade. Data in Indian population are scarce, and hence, the present study was planned to evaluate different doses of cisatracurium. Material and Methods: The prospective randomized double-blind study was conducted on 180 patients of either sex in the age group of 20-60 yrs., having physical status class I to III, scheduled for surgery under general anesthesia. After exclusion 154 patients were randomly divided into three groups comprising 52, 51, and 51, respectively, in Group A, Group B, and group C. They received 0.1 mgkg-1, 0.2 mgkg-1, and 0.3 mgkg-1 of cisatracurium, respectively, to facilitate endotracheal intubation. Time of onset, intubating conditions, hemodynamic parameters, signs of histamine release, and recovery time were noted. Results: Mean time to onset was maximum in group A (4.37 ± 0.48 minutes) and minimum in group C (2.33 ± 0.43 minutes). Intubating conditions were found excellent in 88% patients in group. Change in HR was found to be non-significant at all time periods, but decrease in MAP was found between 2 and 10 minutes in group C. Duration of action was longest in group C. Conclusion: We conclude that cisatracurium in dose of 0.2 mgkg-1 and 0.3 mgkg-1 provides good-to-excellent intubating conditions within less than 3 minutes.

Use of rocuronium and sugammadex for video-assisted thoracoscopic surgery is associated with reduced duration of chest tube drainage: a propensity score-matched analysis.

BACKGROUND: We investigated the influence of different neuromuscular blocking agents and reversal agents during anaesthesia on early removal of chest tube drainage after video-assisted thoracoscopic surgery (VATS). METHODS: This retrospective single-centre study included patients who underwent VATS after tracheal intubation under general anaesthesia. Patients received either cisatracurium and neostigmine (n=547) or rocuronium and sugammadex (n=151). Quantitative neuromuscular monitoring was used and one chest tube (size 24 Fr) was inserted. To reduce potential bias, 140 patients from each group were matched by propensity score for sex, age, body mass index and indication for VATS. Primary outcome was duration of chest tube drainage after surgery. RESULTS: Use of rocuronium and sugammadex was associated with a shorter duration of chest tube drainage (2 [1-2] vs 2 [1-3] days; P=0.049) and a 63% reduction in delayed chest tube removal (odds ratio 0.37; 95% confidence interval [CI]: 0.20-0.67; P=0.005). This group also had a lower incidence of postoperative atelectasis (P=0.047) and consolidation (P=0.008). Each 1 h increase in the duration of anaesthesia was associated with a 1.57-fold increase in the delayed removal of the chest tube (95% CI: 1.25-1.96; P=0.005). CONCLUSIONS: During general anaesthesia for VATS, compared with cisatracurium and neostigmine, use of rocuronium and sugammadex was associated with a significant decrease in the incidence of postoperative delayed removal of the chest tube, atelectasis, and pulmonary consolidation.

Efficacy and Safety of Cisatracurium Compared to Vecuronium for Neuromuscular Blockade in Acute Respiratory Distress Syndrome.

PURPOSE: Previous studies analyzing neuromuscular blocking agents (NMBAs) in acute respiratory distress syndrome (ARDS) have evaluated the benefit of cisatracurium with conflicting results, and data evaluating other NMBAs remains limited. The objective of this study was to compare the efficacy and safety of cisatracurium to vecuronium in ARDS. MATERIALS AND METHODS: A single-center, retrospective, propensity matched review of patients who received cisatracurium or vecuronium continuous infusions between October 1, 2017 and June 30, 2020 for ARDS was conducted. The primary endpoint was duration of mechanical ventilation. Secondary endpoints included change in PaO2/FiO2 ratio at 48 h, intensive care unit (ICU) and hospital mortality, and ICU and hospital length of stay (LOS). Safety endpoints included newly developed myopathy, presence of bradycardia or hypotension, and newly developed barotrauma or volutrauma. RESULTS: Twenty-nine patients were included in each group. There was no statistically significant difference in the primary endpoint of ventilator days between cisatracurium and vecuronium groups (mean 15.9 vs. 20.5 days respectively; p = .2). No statistically significant differences were found in secondary endpoints of ICU mortality (51.7% vs. 51.7%) or length of stay (18.7 vs. 23.9 days, p = .19), hospital mortality (51.7% vs. 55.2%, p = .79) or length of stay (22 vs. 30.6 days, p = .08), or mean change in PaO2/FiO2 (29.8 vs. 36.6; p = .74). Statistically significant differences were not observed in safety endpoints of myopathy (37.9% vs. 37.9%), barotrauma or volutrauma (13.8% vs. 3.5%; p = .16), bradycardia (31% vs. 13.8%; p = .12), or hypotension (96.6% vs. 82.8%; p = .08). CONCLUSIONS: No significant differences were seen in efficacy or safety endpoints between cisatracurium or vecuronium groups, suggesting that vecuronium may be a safe alternative agent for neuromuscular blockade in ARDS. Results of this analysis warrant confirmation in a larger, randomized study.

Atracurium Versus Cisatracurium in the Treatment of Acute Respiratory Distress Syndrome.

Background: Neuromuscular blocking agents are one of the few medication classes that have demonstrated a clinical benefit in patients with severe acute respiratory distress syndrome (ARDS). However, most literature utilized cisatracurium, and utilization of atracurium is limited to 1 small study. Objective: The purpose of this study was to provide further evidence comparing the safety and efficacy of atracurium versus cisatracurium for the treatment of ARDS. Methods: This multicenter, retrospective, observational cohort noninferiority study was conducted at 3 hospitals within a tertiary health care system. We included subjects diagnosed with ARDS who received either atracurium or cisatracurium for at least 12 hours. The primary outcome measured the change in PaO2/FiO2 (P/F) ratio from baseline to 48 hours after initiation. Results: Baseline characteristics were similar between groups except for a higher median age and a higher proportion of subjects who were COVID-positive in the atracurium group. There were also some noted differences in the baseline P/F ratios. In a multivariable model adjusting for baseline characteristics, the change in the P/F ratio for atracurium was noninferior to cisatracurium at 24, 48, and 72 hours. A significant cost reduction, measured as cost per patient per day, was seen with the use of atracurium ($14.81-$25.16 vs $33.86-$41.91). Conclusion: Atracurium appears to be a safe and cheaper alternative agent in the management of ARDS.

Neuromuscular blockade characteristics of cisatracurium in patients receiving chemotherapy: A preliminary study in breast cancer patients.

Background and Aims: Cancer chemotherapeutic agents cause alteration in the response to neuromuscular blocking drugs, which can have serious perioperative implications. Magnesium, commonly found to be deficient in these patients, plays an indispensable role in neuromuscular transmission. This study aimed to understand the effect of neoadjuvant chemotherapy on the neuromuscular blocking properties of cisatracurium. Material and Methods: One hundred female patients scheduled for breast cancer surgery were divided into two groups (n = 50 each). Group B received neoadjuvant chemotherapy with taxane, adriamycin, and cyclophosphamide, and Group A did not receive neoadjuvant chemotherapy. Neuromuscular block following cisatracurium 0.15 mg/kg was measured using peripheral nerve stimulator at the ulnar nerve. Onset time, duration of intense block, clinical duration of action, time to TOF4 after the last dose of cisatracurium, along with preoperative serum magnesium concentration were measured. Correlation and multiple regression were run to analyze the relationship between history of neoadjuvant chemotherapy, preoperative magnesium, and the abovementioned time points. Mediation analysis was done to ascertain if magnesium was mediating the observed effects. Results: Onset time was prolonged by nearly 18% in Group B compared to Group A (P = 0.001). The duration of intense block was 35.27 ± 8.9 min in Group B and 42.07 ± 10.99 min in Group A (P < 0.001). The clinical duration of action of cisatracurium was significantly shorter in Group B (46.06 ± 8.68 min) compared to Group A (55.87 ± 11.04 min, P < 0.001). The time to TOF4 was 32.86 ± 5.66 min in Group B and 36.57 ± 8.49 min in Group A (P < 0.05). Preoperative serum magnesium levels were significantly lower in Group B (P < 0.001). Conclusion: Patients who had received neoadjuvant chemotherapy had a delayed onset, shorter duration of action, and faster recovery for cisatracurium. Although preoperative magnesium levels were lower in Group B, it was found to be an independent predictor rather than a mediator of these effects.

[Effect of Cisatracurium to Intensify Diaphragmatic Atrophy in Mechanically Ventilated Rats].

OBJECTIVE: To investigate the role of cisatracurium in diaphragm atrophy in mechanically ventilated (MV) rats and its possible mechanism. METHODS: 30 adult male Sprague-Dawley (SD) rats were randomly assigned to 5 groups: Rats in the control (CON) group ( n=6) were fasted for 30 h without any other intervention; rats in the MV group ( n=6) were fasted for 6 h, and then mechanically ventilated for 24 h while receiving continuous infusion of sodium pentobarbital and 0.9% NaCl; rats in the MV+cisatracurium (MVC) group ( n=6) were fasted for 6 h, and then mechanically ventilated for 24 h while receiving continuous infusion of sodium pentobarbital and cisatracurium; rats in the MV+chloroquine (QMV) group ( n=6) and rats in the MV+cisatracurium+chloroquine (QMVC) group ( n=6) received intraperitoneal injection of chloroquine (30 mg/kg), an autophagy inhibitor, at 24 h and 30 min prior to MV in addition to the treatments given to the MV group and the MVC group, respectively. The rats in each group were sacrificed 30 hours later, and costal diaphragm muscle specimens were collected. The cross-sectional area (CSA) of the diaphragm fibers was observed through HE staining, and the colocalizations of TOM20 and LC3 were assessed by immunofluorescence staining. The expression levels of PINK1, Parkin, P62 and LC3, the mitophagy-related proteins, and the expression levels of MAFbx and MURF-1, muscular-atrophy-related proteins, were evaluated by Western blot. RESULTS: Respective comparisons of the MV group with the CON group and the MVC group with the MV group showed that the CSA decreased ( P<0.05), the expression of MURF-1, MAFbx, PINK1, Parkin and LC3Ⅱ/Ⅰproteins increased ( P<0.05), the number of co-expressed mitochondria of TOM20 and LC3 and the expression of LC3 increased and the expression of P62 protein decreased ( P<0.05) in the MV and MVC groups. Respective comparisons of the QMV group with the MV group and the QMVC group with the MVC group showed that the CSA increased ( P<0.05), the expression of MURF-1, MAFbx, PINK1, Parkin and LC3Ⅱ/Ⅰ proteins increased ( P<0.05), the number of co-expressed mitochondria of TOM20 and LC3 and the expression of LC3 decreased and the expression of P62 protein decreased ( P<0.05) in the QMV and QMVC group. CONCLUSION: Mechanical ventilation for 24 h caused diaphragm atrophy in SD rats. Cisatracurium may aggravate diaphragm atrophy in mechanically ventilated rats through the autophagy-lysosome (AL) pathway, a process that may be related to the PINK1/Parkin-mediated mitophagy, and chloroquine may reduce diaphragmatic atrophy induced by cisatracurium by blocking the AL pathway.

Comparison of hemodynamic changes and serum potassium levels in the use of succinylcholine and cisatracurium in electroconvulsive therapy.

BACKGROUND: Electroconvulsive therapy (ECT) is nowadays used commonly as one the most effective treatment methods in psychiatric disorders. In patients undergoing ECT, succinylcholine is usually used. In addition, cisatracurium is occasionally used on a case report basis globally. In this study, we compared the hemodynamic changes and serum potassium levels in the use of succinylcholine and cisatracurium in ECT. MATERIALS AND METHODS: The current crossover clinical trial was performed on 45 patients who were candidates for ECT between 2017 and 2018. The patients were given succinylcholine or cisatracurium randomly on two separate occasions of ECT. The independent t-test and Chi square Test were used to compare the data. RESULTS: Comparison of mean systolic blood pressure (P = 0.14), diastolic blood pressure (P = 0.33), and mean arterial pressure (P = 0.23) did not show any significant difference between the two groups. The induced seizure duration (P = 0.002), return of spontaneous respiratory from seizure ending (P = 0.001), and apnea duration (P = 0.01) were significantly higher in the cisatracurium group compared to the succinylcholine group. However, the frequency of tachycardia in cisatracurium group was lower than the succinylcholine group (P < 0.001). In addition, the serum potassium level had a significant difference (P < 0.001) between the two groups. CONCLUSION: Using cisatracurium can be an alternative to succinylcholine during ECT since it causes less elevation in serum potassium and creates a longer duration of induced seizure, more rapid re emergence of spontaneous breathing at the end of seizure (P = 0.001), and a lower prevalence of tachycardia compared to succinylcholine (P < 0.001).

Cisatracurium stimulates testosterone synthesis in rat and mouse Leydig cells via nicotinic acetylcholine receptor.

As a cis-acting non-depolarizing neuromuscular blocker through a nicotinic acetylcholine receptor (nAChR), cisatracurium (CAC) is widely used in anaesthesia and intensive care units. nAChR may be present on Leydig cells to mediate the action of CAC. Here, by Western blotting, immunohistochemistry and immunofluorescence, we identified that CHRNA4 (a subunit of nAChR) exists only on rat adult Leydig cells. We studied the effect of CAC on the synthesis of testosterone in rat adult Leydig cells and mouse MLTC-1 tumour cells. Rat Leydig cells and MLTC-1 cells were treated with CAC (5, 10 and 50 µmol/L) or nAChR agonists (50 µmol/L nicotine or 50 µmol/L lobeline) for 12 hours, respectively. We found that CAC significantly increased testosterone output in rat Leydig cells and mouse MLTC-1 cells at 5 µmol/L and higher concentrations. However, nicotine and lobeline inhibited testosterone synthesis. CAC increased intracellular cAMP levels, and nicotine and lobeline reversed this change in rat Leydig cells. CAC may increase testosterone synthesis in rat Leydig cells and mouse MLTC-1 cells by up-regulating the expression of Lhcgr and Star. Up-regulation of Scarb1 and Hsd3b1 expression by CAC was also observed in rat Leydig cells. In addition to cAMP signal transduction, CAC can induce ERK1/2 phosphorylation in rat Leydig cells. In conclusion, CAC binds to nAChR on Leydig cells, and activates cAMP and ERK1/2 phosphorylation, thereby up-regulating the expression of key genes and proteins in the steroidogenic cascade, resulting in increased testosterone synthesis in Leydig cells.

Cisatracurium inhibits the proliferation, migration and invasion of breast cancer cells by regulating the expression of miR-3174.

Breast cancer is a type of cancer that begins in the breast tissue. Being a woman is the most important factor in the risk of breast cancer. Although men also get the cancer, women are much more likely to get it. This experiment was founded to investigate the effect and mechanism of Cisatracurium on breast cancer cell proliferation, migration and invasion. Breast cancer cells MDA-MB-231 were cultured in vitro. MDA-MB-231 cells were treated with cisatracurium of different concentrations for 48 h. CCK-8method detected cell proliferation, Transwell detected cell migration and invasion, Western Blot method detected the expression levels of CyclinD1, p21, MMP-2andMMP-9protein in cells, RT-qPCR) detected the expression level of miR-3174in cells. After miR-3174 inhibitor was transfected into MDA-MB-231 in order to down-regulate the expression of miR-3174, the same methods as above were used to observe the effect of the down-regulating miR-3174 expression on MDA-MB-231 cell proliferation, migration and invasion as well as the expression levels of CyclinD1, p21, MMP -2 andMMP-9 protein. After different concentrations of Cisatracurium acted on MDA-MB-231 cells, the cell inhibition rate and p21 protein expression were significantly increased (p<0.05), the number of cell migration and invasion and the expression levels of CyclinD1, MMP-2 and MMP-9 were significantly reduced (p<0.05), and the expression of miR-3174 in cells was significantly reduced (p<0.05). After down-regulating the expression of miR-3174, the cell inhibition rate and p21 protein expression were significantly increased (p<0.05), the number of cell migration and invasion and the expression levels of CyclinD1, MMP-2 and MMP-9 were significantly reduced (p<0.05). Up-regulating miR-3174 expression could reverse the effect of Cisatracurium on the proliferation, migration and invasion of MDA-MB-231 cells. Cisatracurium can inhibit the proliferation, migration and invasion of breast cancer MDA-MB-231 cells, and its mechanism is related to the down-regulation of miR-3174 expression in cells.

Abnormal cisatracurium pharmacodynamics and pharmacokinetics among patients with severe aortic regurgitation during anesthetic induction.

BACKGROUND: This study was designed to examine whether severe aortic regurgitation will affect the pharmacodynamics (PD) and pharmacokinetics (PK) of cisatracurium during anesthetic induction. METHODS: A total of 32 patients were divided into two groups: the AR group (n = 16) and the control group (n = 16). Arterial blood samples were drawn before and at 1, 2, 4, 6, 8, 10, 16 and 20 min after intravenous injection of 0.15 mg/kg cisatracurium. TOF tests were applied to determine the onset time of maximal muscle relaxation. The concentration of cisatracurium in plasma was determined by high-performance liquid chromatography. RESULTS: The onset time to maximal neuromuscular block was prolonged from 2.07 ± 0.08 min to 4.03 ± 0.14 min, which indicated that the PD responses to cisatracurium were significantly delayed in the AR group (P < 0.05) compared to the control group. A conventional two-compartment PK model showed a higher plasma concentration of cisatracurium among the AR group with markedly reduced intercompartment transfer rate (K12 = 0.19 ± 0.02 and K21 = 0.11 ± 0.01 in the AR group vs. K12=0.26 ± 0.01 and K21 = 0.19 ± 0.01 in the control group, P < 0.01) compared to the control group. CONCLUSION: Backward blood flow during diastole in severe AR impaired distribution of cisatracurium from the central compartment to the peripheral compartment, which accounted for the lagged PD responses. Findings in this study underlie the importance of muscular blockade monitoring among patients with severe aortic regurgitation during anesthetic induction. REGISTRATION: Name of the registry: Abnormal Cisatracurium Pharmacodynamics and Pharmacokinetics among Patients with Severe Aortic Regurgitation during Anesthetic Induction. TRIAL REGISTRATION NUMBER: ChiCTR1800019654. Date of registration: November 20th 2018.

The median effective dose (ED50) of cis-Atracurium for laryngeal mask airway insertion during general Anaesthesia for patients undergoing urinary surgery.

BACKGROUND: In clinical practice, the laryngeal mask airway is an easy-to-use supraglottic airway device. However, the cis-atracurium dosage for laryngeal mask insertion has not been standardised. We aimed to determine the optimal dose of cis-atracurium using a sequential method for successful laryngeal mask insertion. METHODS: The cohort study protocol is registered at clinicaltrial.gov (NCT-03668262). Twenty-three patients undergoing elective urinary surgery were sequentially administered cis-atracurium doses as follows: 150, 100, 70, 50, 30, and 20 µg·kg- 1. The main outcome involved the determination of the response to laryngeal mask airway insertion: ≥16 points and < 16 points indicated "satisfactory" and "unsatisfactory" responses, respectively. The median effective dose was estimated using the mean of the seven crossovers from "satisfactory" and "unsatisfactory" responses. The primary outcome involved the determination of the median effective dose (ED50) of cis-atracurium for laryngeal mask airway insertion. RESULTS: The median effective dose of cis-atracurium was 26.5 µg·kg- 1 (95% CI 23.6-29.8) using the sequential method. Heart rate was decreased in the 50 µg·kg- 1 group compared to that in the 30 µg·kg- 1 group at timepoints T7, T8, and T10 (P = 0.0482, P = 0.0460, and P = 0.0236, respectively), but no difference was observed in the 20 µg·kg- 1 group. Systolic blood pressure was decreased in the 50 µg·kg- 1 group compared to that in the 20 µg·kg- 1 group at timepoints T2, T3, and T4 (P = 0.0159, P = 0.0233, and P = 0.0428, respectively). The train-of-four value was significantly lower in the 50 µg·kg- 1 group than in the 30 µg·kg- 1 group at timepoint T3 (P = 0.0326). CONCLUSIONS: The ED50 of cis-atracurium was 26.5 µg·kg- 1 for laryngeal mask airway insertion. TRIAL REGISTRATION: Clinicaltrial.gov Registry, NCT03668262, Registered on 11 September 2018.

First derivative synchronous spectrofluorimetric method for the simultaneous determination of propofol and cisatracurium besylate in biological fluids.

Propofol and cisatracurium besylate have been simultaneously determined using a highly sensitive first derivative synchronous spectrofluorometric method. The method is based on measuring first derivative synchronous spectrofluorimetric amplitude at Δλ = 40 nm with a scanning rate of 600 nm/min. The different experimental parameters affecting the fluorescence intensity of the two drugs were carefully studied and optimized. The amplitude-concentration plots were rectilinear over the range 40.0-400.0 ng/mL and 20.0-280.0 ng/mL for propofol and cisatracurium, respectively with lower detection limits of 4.0 and 2.35 ng/mL and quantification limits of 12.1 and 7.1 ng/mL for propofol and cisatracurium, respectively. The proposed method was successfully applied for the determination of the two compounds in synthetic mixtures and in commercial ampoules. The high sensitivity attained using the proposed method allowed the simultaneous determination of both drugs in spiked plasma samples. The mean % recoveries in spiked human plasma (n = 3) were 96.53 ± 0.90 and 96.20 ± 1.64 for each of propofol and cisatracurium, respectively. The method was validated in compliance with International Council of Harmonization (ICH) Guidelines.

Comparison of the neuromuscular blocking effects of cisatracurium during isoflurane or propofol anesthesia in dogs.

OBJECTIVE: To compare the neuromuscular blocking effects of cisatracurium during isoflurane versus propofol anesthesia in dogs. STUDY DESIGN: Prospective, randomized study. ANIMALS: A total of 20 healthy, client-owned dogs (16 females, four males) weighing 12.5-22 kg and aged 1-8 years. METHODS: Dogs undergoing elective surgery were randomized in equal numbers to an isoflurane (ISO) or propofol (PPF) group. Other drugs used during anesthesia were equal between groups. Single-twitch (ST) stimulation was used to monitor neuromuscular response. After recording the baseline ST (T0), cumulative doses of cisatracurium (0.05 mg kg-1) were administered intravenously until ST/T0 ≤5%. Effective doses 50 (ED50) and 95 (ED95) of cisatracurium in each group were calculated from group dose-response curves. Recovery of ST (TR) was defined as spontaneous recovery of ST to 80-120% of T0 remaining stable for 2 minutes. The ST after each dose of cisatracurium, duration 25% (time after the last dose until 25% recovery of TR), recovery index (time to recovery from 25% to 75% of TR) and duration to TR (time after the last dose until recovery of TR) were recorded. RESULTS: Incremental doses of cisatracurium, median (range), were 2 (1-3) in ISO and 4 (2-5) in PPF to achieve ≥95% depression of ST/T0 (p < 0.01). ED50 and ED95 were 20 µg kg-1 and 117 µg kg-1 in ISO and 128 µg kg-1 and 167 µg kg-1 in PPF, respectively. The duration 25%, recovery index and duration to TR, median (range), were longer in ISO [22.6 (10.3-24.3), 5.3 (3.0-7.8) and 36.1 (20.1-49.7) minutes, respectively] than in PPF [10.2 (6.8-16.5), 3.0 (2.0-3.8) and 17.7 (14.2-28.7) minutes, respectively] (p < 0.01). CONCLUSIONS AND CLINICAL RELEVANCE: Cisatracurium-induced neuromuscular blockade was significantly enhanced and prolonged by isoflurane compared with propofol.

Early Skin Test after Anaphylaxis during Induction of Anesthesia: A Case Report.

BACKGROUND: It is recommended that a skin test be performed 4-6 weeks after anaphylaxis. However, there is little evidence about the timing of the skin test when there is a need to identify the cause within 4-6 weeks. CASE REPORT: A 57-year-old woman was scheduled to undergo surgery via a sphenoidal approach to remove a pituitary macroadenoma. Immediately after the administration of rocuronium, pulse rate increased to 120 beats/min and blood pressure dropped to 77/36 mmHg. At the same time, generalized urticaria and tongue edema were observed. Epinephrine was administered and the surgery was postponed. Reoperation was planned two weeks after the event. Four days after the anaphylactic episode, rocuronium was confirmed to be the cause by the skin prick test. Cisatracurium, which showed a negative reaction, was selected as an alternative agent for future procedures. Two weeks later, the patient underwent reoperation without any adverse events. CONCLUSIONS: The early skin test can be performed if there is a need even earlier than 4-6 weeks after anaphylaxis.

Intraoperative Use of Nondepolarizing Neuromuscular Blocking Agents During Cardiac Surgery and Postoperative Pulmonary Complications: A Prospective Randomized Trial.

OBJECTIVE: Nondepolarizing neuromuscular blocking agents (NMBAs) are associated with perioperative complications in noncardiac surgery; however, little is known about their effect on cardiac surgery. This study assessed the effect of neuromuscular blockade (NMB) on the incidence of postoperative pulmonary complications (PPCs) after cardiac surgery and operating conditions. DESIGN: Prospective, randomized clinical trial with blinded outcomes assessment. SETTING: University hospital, single institution. PARTICIPANTS: Adult patients having cardiac surgery requiring cardiopulmonary bypass. INTERVENTIONS: One hundred patients were randomized to receive succinylcholine (group SUX) for intubation with no further NMB administered or cisatracurium (group CIS) for intubation and maintenance NMB. The primary outcome was a composite incidence of PPCs in the 72 hours after elective cardiac surgery. PPCs included failure to extubate within 24 hours, need for reintubation, pneumonia, aspiration, unanticipated need for noninvasive respiratory support, acute respiratory distress, and mortality from respiratory arrest. The secondary outcome was the adequacy of operating conditions as assessed by blinded surgeon survey (including a rating of surgical conditions on a Likert scale from 1 = poor to 5 = excellent), anesthesiologist report, and patient questionnaire. MEASUREMENTS AND MAIN RESULTS: The composite incidence of PPCs did not differ between groups (8 of 50 patients in both groups; 16%). Mean surgeon rating of surgical conditions was lower in the SUX group (4.65 ± 0.85 v 4.96 ± 0.20, p = 0.02). CONCLUSION: Although avoiding nondepolarizing NMBA is feasible, doing so worsened operating conditions and did not reduce the incidence of postoperative pulmonary complications.

Neuromuscular block monitoring after the administration of 1 mg/kg intravenous cis-atracurium in the anaesthetized pig.

Neuromuscular blocking agents should be included as part of a balanced anaesthetic protocol to improve anaesthetic management, although doses are not always established for each species. Cis-atracurium is a benzylisoquinolinium neuromuscular blocking agent with an intermediate duration of action devoid of significant adverse effects previously used in pigs with a wide dosage range. Cis-atracurium was administered at 1 mg/kg bolus to sixteen pigs to establish its time profile and effects. The pigs were premedicated intramuscularly with 4 mg/kg azaperone, 8 mg/kg ketamine and 0.2 mg/kg morphine IM and maintained with isoflurane in oxygen. After cis-atracurium administration, neuromuscular monitoring via acceleromyography was started until the recovery of the 90% of the train of four ratio. Complete decrease in the train of four ratio was accomplished in eleven pigs. Onset of action was 70 s, with a recovery of the fourth twitch at 26 min and a recovery of a train of four ratio greater than 90% in 60 min. In conclusion, 1 mg/kg intravenous cis-atracurium in the pig allowed for a rapid onset of action and a complete recovery after 60 min although high variability in the time profile is seen.

Effect of age on cis-atracurium besylate pharmacokinetics following a single 1 mg kg-1 intravenous bolus in young pigs.

OBJECTIVE: To determine the cis-atracurium pharmacokinetic data and laudanosine production of a single 1 mg kg-1 cis-atracurium dose in the pig and to compare the pharmacokinetics between two groups of different ages. STUDY DESIGN: Prospective experimental study. ANIMALS: Sixteen female pigs in two groups. Group A included eight animals aged 2.0-2.5 months and weighed 26.6 ± 3.6 kg. Group B included eight animals aged 4.0-5.0 months and weighed 57.4 ± 8.3 kg. METHODS: The pigs were anaesthetized and monitored throughout the procedure. Arterial blood samples collected at 0, 0.5, 1, 2, 5, 10, 20, 30, 45, 60, 90, 120 and 180 minutes after cis-atracurium injection were cooled and centrifuged. Plasma was acidified and stored at -20 °C for subsequent cis-atracurium and laudanosine analyses. RESULTS: Anaesthetic parameters were within normal ranges throughout the procedure. Plasma cis-atracurium and laudanosine concentrations were measured for the 16 pigs. Elimination rate constant, elimination half-life, area under the curve, mean residence time, distribution volume and total clearance were calculated for each pig. Statistical differences (p < 0.05) in the elimination rate constant, elimination half-life, mean residence time and distribution volume values were observed between the two groups. Elimination half-life, mean residence time and distribution volume values were higher and elimination rate constant lower in younger pigs than in older pigs. No plasma laudanosine concentrations were detected in any pig. CONCLUSION AND CLINICAL RELEVANCE: Longer duration of plasma cis-atracurium concentrations were observed in younger pigs. Distribution volume was also higher in younger pigs. Conversely, total clearance and area under the curve were similar between the two age groups. No laudanosine production was detected, suggesting a different cis-atracurium metabolism in the pig compared with other species.

Extended neuromuscular blockade in acute respiratory distress syndrome does not increase mortality.

BACKGROUND: Neuromuscular blockade (NMB) is often utilized in the treatment of acute respiratory distress syndrome (ARDS). Its use for a period of 48 h has been shown to improve mortality in randomized control trials. We aimed to characterize outcomes associated with a prolonged NMB. We hypothesized that the duration of NMB would not be associated with increased mortality. MATERIALS AND METHODS: This was a retrospective review from June 2014 to October 2016 of patients admitted to the surgical intensive care unit and receiving cisatracurium for ARDS. Patients paralyzed for ≤ 48 h (SHORT) were compared to those paralyzed for longer durations (LONG). Primary outcome was mortality. Parametric and nonparametric tests were utilized for the purposes of the comparison. A multivariate logistic regression model was utilized to adjust for differences. RESULTS: Of 73 patients meeting inclusion criteria, 32 (44%) were SHORT and 41 (56%) LONG. Compared to the LONG cohort, those in SHORT were older (60 versus 52 years, P = 0.04) but were comparable with respect to sex, acute physiology and chronic health evaluation IV scores, presence of concurrent pneumonia, and the use of vasopressors. SHORT patients were less likely to require rescue therapy with inhaled nitric oxide (28% versus 66%, P < 0.01). Overall mortality was 60%. There was no difference in the adjusted odds for mortality (adjusted odds ratio: 0.57, P = 0.33). Secondary outcomes including deep venous thrombosis and pneumonia did not differ between the two groups. CONCLUSIONS: Extended NMB for ARDS was not associated with increased mortality. Discontinuation of this modality should not be based solely on the duration of therapy.