A Practical Dosing Algorithm for Deep Neuromuscular Blockade During Total Intravenous Anesthesia: ROCURITHM

BACKGROUND

The number of trials investigating the effects of deep neuromuscular blockade (NMB) on surgical conditions and patient outcomes is steadily increasing. Consensus on which surgical procedures benefit from deep NMB (a post tetanic count of 1-2) and how to implement it has not been reached. The ESAIC does not advise routine application but recommends use of deep NMB to improve surgical conditions on indication. This study investigates the optimal dosing strategy to reach and maintain adequate deep NMB during total intravenous anesthesia.

METHODS

Data from three trials investigating deep NMB during laparoscopic surgery with TIVA (n=424) was pooled to analyze the required rocuronium dose, when to start continuous infusion and how to adjust. The resulting algorithm was validated (n=32) and compared to the success rate in ongoing studies where the algorithm was not used (n=180).

RESULTS

The mean rocuronium dose based on actual bodyweight for PTC 1-2 was 1.0 ± 0.27 mg.kg -1.h -1 in the trials where mean duration of surgery was ±2 hours (116 minutes). An induction dose of 0.6 mg.kg -1 lead to a PTC of 1-5 in a quarter of patients after a mean of 11 minutes. The remaining patients were equally divided over too shallow (additional bolus and direct start of continuous infusion) or too deep; a ±15-minute wait after PTC 0 for return of PTC to ≥1. Using the proposed algorithm, a mean 76% of all 5-minute measurements throughout surgery were on target PTC 1-2 in the validation cohort. The algorithm performed significantly better than anesthesiology residents without the algorithm, even after a learning curve from 0-20 patients (42% on target, P≤.001, Cohen's d=1.4 [95% CI 0.9, 1.8]) to 81-100 patients (61% on target, P≤.05, Cohen's d=0.7 [95% CI 0.1, 1.2]).

CONCLUSIONS

We propose a dosing algorithm for deep NMB with rocuronium in patients receiving TIVA.

Machine learning based analysis and detection of trend outliers for electromyographic neuromuscular monitoring

PURPOSE

Neuromuscular monitoring is frequently plagued by artefacts, which along with the frequent unawareness of the principles of this subtype of monitoring by many clinicians, tends to lead to a cynical attitute by clinicians towards these monitors. As such, the present study aims to derive a feature set and evaluate its discriminative performance for the purpose of Train-of-Four Ratio (TOF-R) outlier analysis during continuous intraoperative EMG-based neuromuscular monitoring.

METHODS

Patient data was sourced from two devices: (1) Datex-Ohmeda Electromyography (EMG) E-NMT: a dataset derived from a prospective observational trial including 136 patients (21,891 TOF-R observations), further subdivided in two based on the type of features included; and (2) TetraGraph: a clinical case repository dataset of 388 patients (97,838 TOF-R observations). The two datasets were combined to create a synthetic set, which included shared features across the two. This process led to the training of four distinct models.

RESULTS

The models showed an adequate bias/variance balance, suggesting no overfitting or underfitting. Models 1 and 2 consistently outperformed the others, with the former achieving an F1 score of 0.41 (0.31, 0.50) and an average precision score (95% CI) of 0.48 (0.35, 0.60). A random forest model analysis indicated that engineered TOF-R features were proportionally more influential in model performance than basic features.

CONCLUSIONS

Engineered TOF-R trend features and the resulting Cost-Sensitive Logistic Regression (CSLR) models provide useful insights and serve as a potential first step towards the automated removal of outliers for neuromuscular monitoring devices.

TRIAL REGISTRATION

NCT04518761 (clinicaltrials.gov), registered on 19 August 2020.

Good clinical research practice (GCRP) in pharmacodynamic studies of neuromuscular blocking agents III: The 2023 Geneva revision

The set of guidelines for good clinical research practice in pharmacodynamic studies of neuromuscular blocking agents was developed following an international consensus conference in Copenhagen in 1996 (Viby-Mogensen et al., Acta Anaesthesiol Scand 1996, 40, 59-74); the guidelines were later revised and updated following the second consensus conference in Stockholm in 2005 (Fuchs-Buder et al., Acta Anaesthesiol Scand 2007, 51, 789-808). In view of new devices and further development of monitoring technologies that emerged since then, (e.g., electromyography, three-dimensional acceleromyography, kinemyography) as well as novel compounds (e.g., sugammadex) a review and update of these recommendations became necessary. The intent of these revised guidelines is to continue to help clinical researchers to conduct high-quality work and advance the field by enhancing the standards, consistency, and comparability of clinical studies. There is growing awareness of the importance of consensus-based reporting standards in clinical trials and observational studies. Such global initiatives are necessary in order to minimize heterogeneous and inadequate data reporting and to improve clarity and comparability between different studies and study cohorts. Variations in definitions of endpoints or outcome variables can introduce confusion and difficulties in interpretation of data, but more importantly, it may preclude building of an adequate body of evidence to achieve reliable conclusions and recommendations. Clinical research in neuromuscular pharmacology and physiology is no exception.

Evaluation of continuous wound infusion with local analgesics in postoperative renal transplantation patients: A retrospective study

Objectives

The objective is to evaluate the efficacy of the continuous wound infusion (CWI) with Ropivacaine (naropeine 2 mg/ml) on postoperative pain, analgesics consumption, and bowel function in renal transplantation patients.

Materials and Methods

A retrospective study trial including 79 patients who underwent renal transplantation. Patients were separated into two groups (catheter or without catheter). We identified 52 (65.8%) patients who received catheter wound infusion during the first 48 h postoperatively. On the other hand, 27 (34.1%) patients received standard without catheter anesthetic technique. Catheter wound infusion was achieved through a 12 cm catheter, inserted subcutaneously after abdominal closure. The catheter was placed above the external oblique aponeurosis. All postoperative data were examined to evaluate the first postoperative 48 h. This study aims to assess three variables: postoperative pain analysis through a visual analog scale, analgesics consumption, and bowel function.

Results

The overall score of the three variables was studied. Regarding pain assessment, we have determined that the group of patients with catheter scored better than patients without catheter with borderline significance (66.3 vs. 61.2 consecutively; P = 0.0843). An early bowel function was noted in patients with catheters on the 2nd postoperative day (P = 0.0209). Moreover, patients without catheter consumed more painkillers with nonsignificant difference (P = 0.2499).

Conclusion

Patients with catheter showed earlier bowel function than the noncatheter group on the 2nd postoperative day. The catheter group had better pain evaluation.

Peri-operative management of neuromuscular blockade: A guideline from the European Society of Anaesthesiology and Intensive Care

Recent data indicated a high incidence of inappropriate management of neuromuscular block, with a high rate of residual paralysis and relaxant-associated postoperative complications. These data are alarming in that the available neuromuscular monitoring, as well as myorelaxants and their antagonists basically allow well tolerated management of neuromuscular blockade. In this first European Society of Anaesthesiology and Intensive Care (ESAIC) guideline on peri-operative management of neuromuscular block, we aim to present aggregated and evidence-based recommendations to assist clinicians provide best medical care and ensure patient safety. We identified three main clinical questions: Are myorelaxants necessary to facilitate tracheal intubation in adults? Does the intensity of neuromuscular blockade influence a patient's outcome in abdominal surgery? What are the strategies for the diagnosis and treatment of residual paralysis? On the basis of this, PICO (patient, intervention, comparator, outcome) questions were derived that guided a structured literature search. A stepwise approach was used to reduce the number of trials of the initial research ( n  = 24 000) to the finally relevant clinical studies ( n  = 88). GRADE methodology (Grading of Recommendations, Assessment, Development and Evaluation) was used for formulating the recommendations based on the findings of the included studies in conjunction with their methodological quality. A two-step Delphi process was used to determine the agreement of the panel members with the recommendations: R1 We recommend using a muscle relaxant to facilitate tracheal intubation (1A). R2 We recommend the use of muscle relaxants to reduce pharyngeal and/or laryngeal injury following endotracheal intubation (1C). R3 We recommend the use of a fast-acting muscle relaxant for rapid sequence induction intubation (RSII) such as succinylcholine 1 mg kg -1 or rocuronium 0.9 to 1.2 mg kg -1 (1B). R4 We recommend deepening neuromuscular blockade if surgical conditions need to be improved (1B). R5 There is insufficient evidence to recommend deep neuromuscular blockade in general to reduce postoperative pain or decrease the incidence of peri-operative complications. (2C). R6 We recommend the use of ulnar nerve stimulation and quantitative neuromuscular monitoring at the adductor pollicis muscle to exclude residual paralysis (1B). R7 We recommend using sugammadex to antagonise deep, moderate and shallow neuromuscular blockade induced by aminosteroidal agents (rocuronium, vecuronium) (1A). R8 We recommend advanced spontaneous recovery (i.e. TOF ratio >0.2) before starting neostigmine-based reversal and to continue quantitative monitoring of neuromuscular blockade until a TOF ratio of more than 0.9 has been attained. (1C).

A modified TOF-ratio to assess rocuronium-induced neuromuscular block: a comparison with the usual TOF-ratio

BACKGROUND

The TOFscan is an acceleromyographic neuromuscular monitor that calculates and displays two measurements: first, a train-of-four (TOF) ratio, or ratio of the fourth twitch in the TOF-sequence, T4, and the first twitch, T1 (T4/T1). In addition, a second, modified ratio is displayed (T4/Tr), which refers to the ratio between T4 and a reference twitch (Tr), calculated as the mean value of the four twitches in a TOF-sequence [Tr = (T1 + T2 + T3 + T4)/4]. T4/Tr is calculated before establishment of neuromuscular block.

METHODS

This prospective observational study included 35 adult patients. NMB induced by a rocuronium bolus of 0.6 mg/kg was continuously monitored at the adductor pollicis with the TOFscan and both TOF-ratios were simultaneously assessed. Primary outcome was the comparison of recovery to a TOF-ratio ≥ 0.9 calculated as T4/T1 and T4/Tr.

RESULTS

The first value of the T4/T1 ≥ 90% was 90.9 (1.1) % and the simultaneously calculated T4/Tr was 69.6 (9.3) %, P <  0.001. The first value of the T4/Tr ≥ 90% was 90.5 (1.1) %, the simultaneously T4/T1 was 97.3 (2.5) %, P <  0.001. Time from injection of rocuronium to a TOF-ratio ≥ 90% was 56.2 ± 17.1 min for the T4/T1 and 65.3 ± 19.3 min for the T4/Tr, P < 0.001. During onset, a TOF ratio ≤ 20% was reached 145.5 (50.5) s after rocuronium when considering T4/T1, and 114.5 (45) s with the T4/Tr, P <  0.001.

CONCLUSION

The present study shows the limitations of the usually determined acceleromyographic TOF ratio (T4/T1) in determining adequate neuromuscular recovery. The T4/T1 ratio significantly overestimates recovery compared with the T4/Tr ratio. Clinical decisions of adequate neuromuscular recovery based on the new T4/Tr ratio may reduce the incidence of residual paralysis and improve patient safety.

The impact of deep versus standard neuromuscular block on intraoperative safety during laparoscopic surgery: an international multicenter randomized controlled double-blind strategy trial - EURO-RELAX TRIAL

Background

Muscle relaxants are routinely used during anesthesia to facilitate endotracheal intubation and to optimize surgical conditions. However, controversy remains about the required depth of neuromuscular block (NMB) needed for optimal surgical working conditions and how this relates to other outcomes. For instance, a deep neuromuscular block yields superior surgical working conditions compared to a standard NMB in laparoscopic surgery, however, a robust association to other (safety) outcomes has not yet been established.

Methods

Trial design: an international multicenter randomized controlled double-blind strategy trial.

Trial population: 922 patients planned for elective, laparoscopic or robotic, abdominal surgery.

Intervention: Patients will be randomized to a deep NMB (post-tetanic count 1–2 twitches) or standard care (single-dose muscle relaxant administration at induction and repeated only if warranted by surgical team).

Main trial endpoints: Primary endpoint is the difference in incidence of intraoperative adverse events during laparoscopic surgery graded according to ClassIntra® classification (i.e., ClassIntra® grade ≥ 2) between both groups. Secondary endpoints include the surgical working conditions, 30-day postoperative complications, and patients’ quality of recovery.

Discussion

This trial was designed to analyze the effect of deep neuromuscular block compared to standard neuromuscular block on intra- and postoperative adverse events in patients undergoing laparoscopic surgery.

Trial registration

ClinicalTrials.gov NCT04124757(EURO-RELAX); registration URL: https://clinicaltrials.gov/ct2/show/NCT04124757, registered on October 11th, 2019. 

Neuromuscular block in patients 80 years and older: a prospective, controlled study

Background

An increasing number of patients older than 80 years are undergoing anesthesia, but little information is available regarding pharmacodynamic effects of myorelaxants in this population. This study aims to compare the time course of rocuronium neuromuscular block in patients ≥ 80 years with those of younger adults.

Methods

Under total intravenous anesthesia with propofol and sufentanil, time course of a bolus of rocuronium 0.6 mg/kg neuromuscular block was assessed with acceleromyography in patients ≥ 80 and in patients 20–50 years old. Onset time, clinical duration, duration until 90% and 100% recovery of baseline were determined.

Results

Data from 32 patients were analyzed, 16 were ≥ 80 years and 16 were 20–50 years old. Demographic data are shown in Table 1. In the group ≥ 80, onset time was 190 s ± 46 s compared to 123 s ± 40 s in the group 20–50, P < 0.001 and the clinical duration was 52 [48–69.5] min and 36 [34–41] min, respectively, P < 0.001. Duration to 90% recovery of baseline was 77.5 [71–88.5] min and duration to 100% recovery of baseline was 91.2 [82.2–98] min in patients ≥ 80 years and the corresponding values in the patients 20–50 years old were 53.5 [49–55.5] min and 59.5 [56.5–70.25] min, respectively, P < 0.001.

Conclusion

Compared to younger adults rocuronium shifted in patients ≥ 80 years from a rapid onset, intermediate acting compound to a slower onset, long-acting compound.

Trial registration

ClinicalTrials.gov identifier: NCT03551652 (29/05/2018).

Impact of rocuronium on intraoperative neuromonitoring vagal amplitudes during thyroidectomy

PURPOSE

Neuromuscular blocking agents (NMBA) facilitate endotracheal intubation and reduce related laryngeal morbidity. However, NMBA interfere with intraoperative neuromonitoring amplitudes during thyroidectomy. The goal of this study was to evaluate the impact of rocuronium used for tracheal intubation on early intraoperative neuromonitoring vagal amplitudes observed during first thyroid lobe dissection.

METHODS

This is an observational pharmacoepidemiological study with prospective data collection and retrospective analysis. During the study period, all consecutive patients who underwent thyroid surgery with neuromonitoring were included. Patients underwent endotracheal intubation either using a single dose of rocuronium (NMBA group) or without NMBA (NMBA-free group) according to the anesthesiologist's preference.

RESULTS

Six hundred six patients were included (213 NMBA and 393 NMBA-free group patients). At V1, 39 patients (18%) in the NMBA group had an amplitude < 100 µV (need for curarization reversal in 30 patients) and 13 patients (3.3%) in the NMBA-free group (p < 0.001). In the remaining 554 patients, the mean V1 amplitude was significantly decreased in the NMBA group (544 versus 685 µV; p < 0.001). After exclusion of 25 patients with loss of signal types 1 and 2 during dissection, the difference between mean V1 and mean V2 was significantly lower in NMBA group patients (- 22 versus - 86 µV; p = 0.016).

CONCLUSION

This study provides new data showing how NMBA used for tracheal intubation significantly decrease V1 amplitude baseline and modify amplitude variations from V1 to V2 values during the first thyroid lobe dissection.

LEVEL OF EVIDENCE

Pharmacoepidemiological study.

Does deep neuromuscular blockade during laparoscopy procedures change patient, surgical, and healthcare resource outcomes? A systematic review and meta-analysis of randomized controlled trials

Background

Deep neuromuscular blockade may facilitate the use of reduced insufflation pressure without compromising the surgical field of vision. The current evidence, which suggests improved surgical conditions compared with other levels of block during laparoscopic surgery, features significant heterogeneity. We examined surgical patient- and healthcare resource use-related outcomes of deep neuromuscular blockade compared with moderate neuromuscular blockade in adults undergoing laparoscopic surgery.

Methods

We conducted a systematic literature review according to the quality standards recommended by the Cochrane Handbook for Systematic Reviews. Randomized controlled trials comparing outcomes of deep neuromuscular blockade and moderate neuromuscular blockade among adults undergoing laparoscopic surgeries were included. A random-effects model was used to conduct pair-wise meta-analyses.

Results

The systematic literature review included 15 studies—only 13 were analyzable in the meta-analysis and none were judged to be at high risk of bias. Compared with moderate neuromuscular blockade, deep neuromuscular blockade was associated with improved surgical field of vision and higher vision quality scores. Also, deep neuromuscular blockade was associated with a reduction in the post-operative pain scores in the post-anesthesia care unit compared with moderate neuromuscular blockade, and there was no need for an increase in intra-abdominal pressure during the surgical procedures. There were minor savings on resource utilization, but no differences were seen in recovery in the post-anesthesia care unit or overall length of hospital stay with deep neuromuscular blockade.

Conclusions

Deep neuromuscular blockade may aid the patient and physician surgical experience by improving certain patient outcomes, such as post-operative pain and improved surgical ratings, compared with moderate neuromuscular blockade. Heterogeneity in the pooled estimates suggests the need for better designed randomized controlled trials.

The impact of intra-abdominal pressure on perioperative outcomes in laparoscopic cholecystectomy: a systematic review and network meta-analysis of randomized controlled trials

Background

Laparoscopic cholecystectomy involves using intra-abdominal pressure (IAP) to facilitate adequate surgical conditions. However, there is no consensus on optimal IAP levels to improve surgical outcomes. Therefore, we conducted a systematic literature review (SLR) to examine outcomes of low, standard, and high IAP among adults undergoing laparoscopic cholecystectomy.

Methods

An electronic database search was performed to identify randomized controlled trials (RCTs) that compared outcomes of low, standard, and high IAP among adults undergoing laparoscopic cholecystectomy. A Bayesian network meta-analysis (NMA) was used to conduct pairwise meta-analyses and indirect treatment comparisons of the levels of IAP assessed across trials.

Results

The SLR and NMA included 22 studies. Compared with standard IAP, on a scale of 0 (no pain at all) to 10 (worst imaginable pain), low IAP was associated with significantly lower overall pain scores at 24 h (mean difference [MD]: − 0.70; 95% credible interval [CrI]: − 1.26, − 0.13) and reduced risk of shoulder pain 24 h (odds ratio [OR] 0.24; 95% CrI 0.12, 0.48) and 72 h post-surgery (OR 0.22; 95% CrI 0.07, 0.65). Hospital stay was shorter with low IAP (MD: − 0.14 days; 95% CrI − 0.30, − 0.01). High IAP was not associated with a significant difference for these outcomes when compared with standard or low IAP. No significant differences were found between the IAP levels regarding need for conversion to open surgery; post-operative acute bleeding, pain at 72 h, nausea, and vomiting; and duration of surgery.

Conclusions

Our study of published trials indicates that using low, as opposed to standard, IAP during laparoscopic cholecystectomy may reduce patients’ post-operative pain, including shoulder pain, and length of hospital stay. Heterogeneity in the pooled estimates and high risk of bias of the included trials suggest the need for high-quality, adequately powered RCTs to confirm these findings.

Electronic supplementary material

The online version of this article (10.1007/s00464-020-07527-2) contains supplementary material, which is available to authorized users.

Guidelines on muscle relaxants and reversal in anaesthesia

OBJECTIVES

To provide an update to the 1999 French guidelines on "Muscle relaxants and reversal in anaesthesia", a consensus committee of sixteen experts was convened. A formal policy of declaration and monitoring of conflicts of interest (COI) was developed at the outset of the process and enforced throughout. The entire guidelines process was conducted independently of any industrial funding (i.e. pharmaceutical, medical devices). The authors were required to follow the rules of the Grading of Recommendations, Assessment, Development and Evaluation (GRADE®) system to assess the quality of the evidence on which the recommendations were based. The potential drawbacks of making strong recommendations based on low-quality evidence were stressed. Few of the recommendations remained ungraded.

METHODS

The panel focused on eight questions: (1) In the absence of difficult mask ventilation criteria, is it necessary to check the possibility of ventilation via a facemask before muscle relaxant injection? Is it necessary to use muscle relaxants to facilitate facemask ventilation? (2) Is the use of muscle relaxants necessary to facilitate tracheal intubation? (3) Is the use of muscle relaxants necessary to facilitate the insertion of a supraglottic device and management of related complications? (4) Is it necessary to monitor neuromuscular blockade for airway management? (5) Is the use of muscle relaxants necessary to facilitate interventional procedures, and if so, which procedures? (6) Is intraoperative monitoring of neuromuscular blockade necessary? (7) What are the strategies for preventing and treating residual neuromuscular blockade? (8) What are the indications and precautions for use of both muscle relaxants and reversal agents in special populations (e.g. electroconvulsive therapy, obese patients, children, neuromuscular diseases, renal/hepatic failure, elderly patients)? All questions were formulated using the Population, Intervention, Comparison and Outcome (PICO) model for clinical questions and evidence profiles were generated. The results of the literature analysis and the recommendations were then assessed using the GRADE® system.

RESULTS

The summaries prepared by the SFAR Guideline panel resulted in thirty-one recommendations on muscle relaxants and reversal agents in anaesthesia. Of these recommendations, eleven have a high level of evidence (GRADE 1±) while twenty have a low level of evidence (GRADE 2±). No recommendations could be provided using the GRADE® system for five of the questions, and for two of these questions expert opinions were given. After two rounds of discussion and an amendment, a strong agreement was reached for all the recommendations.

CONCLUSION

Substantial agreement exists among experts regarding many strong recommendations for the improvement of practice concerning the use of muscle relaxants and reversal agents during anaesthesia. In particular, the French Society of Anaesthesia and Intensive Care (SFAR) recommends the use of a device to monitor neuromuscular blockade throughout anaesthesia.

[Hybrid operating theater]

A hybrid suite is an operating theater with imaging equipment equivalent to that used in an angiography suite with computed tomography (CT) and magnetic resonance imaging (MRI). They are often situated outside the operating room area and typically serve as multifunctional rooms designed to support a variety of catheter-based endovascular procedures and open surgery to be performed in the same location. The possibility to perform these in the same location facilitates the combination of both approaches to so-called hybrid procedures. Typical clinical applications of hybrid suites are cardiac, thoracic and vascular surgery, neurosurgery and neuroradiology, as well as orthopedics and traumatology. Transcatheter aortic valve implantation (TAVI) is significantly less invasive than a classical approach by open surgery. Patients older than 75 years with relevant comorbidities benefit most from the minimally invasive interventional approach. There has been a paradigm shift in the management of vascular diseases from open surgical repair to new percutaneous endovascular interventions with good early outcomes. Of particular interest in this context is the ability to block the part of the aorta proximal to the aneurysm with a catheter-based dilatation balloon. Progress in image fusion technology and intraoperative navigation has led to an increased acceptance of hybrid suites in orthopedics and traumatology. The complex care of high-risk patients most often outside the operating theater area is a challenge for the anesthesia team. This demands meticulous planning on behalf of the anesthesiologist to ensure an appropriate and safe strategy for anesthesia, intraoperative monitoring, vascular access and the need for additional equipment. A thorough understanding of the complexity of procedures is vital and a series of questions must be addressed: what is needed to safely administer anesthesia in this environment? What additional resources would be needed for an emergency situation? Is the patient being kept safe from radiation hazards? Moreover, logistics may become an issue as the hybrid suite is most often delocalized. In addition, many procedures realized in a hybrid suite require a multidisciplinary approach and therefore teamwork and professional communication are mandatory. Anesthesiologists need to have an integral role in the hybrid suite team, understanding and anticipating the risks for patients and leading the organization of workflow. The challenge in anesthesia is to ensure that when patients are taken to these complex environments the resources available enable high standards of care to be provided. With future developments in imaging technology combined with more powerful hardware and software, a far greater integration of all these imaging and navigation technologies will be seen in future operating rooms. Finally, patients are becoming more aware of medical developments via the world wide web and increasingly request what they consider to be state of the art treatment.

[Residual neuromuscular blockade]

Even small degrees of residual neuromuscular blockade, i. e. a train-of-four (TOF) ratio >0.6, may lead to clinically relevant consequences for the patient. Especially upper airway integrity and the ability to swallow may still be markedly impaired. Moreover, increasing evidence suggests that residual neuromuscular blockade may affect postoperative outcome of patients. The incidence of these small degrees of residual blockade is relatively high and may persist for more than 90 min after a single intubating dose of an intermediately acting neuromuscular blocking agent, such as rocuronium and atracurium. Both neuromuscular monitoring and pharmacological reversal are key elements for the prevention of postoperative residual blockade.

Biological evaluation of the effect of sugammadex on hemostasis and bleeding

BACKGROUND

Notification of sugammadex has been supplemented with a section on hemostasis, including a longer clotting time in the first minutes following injection, without any documented clinical consequences. The objective of this observational study was to analyze the effects of sugammadex administration on routine coagulation tests and bleeding in the clinical setting.

METHODS

After Institutional Review Board approval, a prospective observational study was conducted between January and December 2011. Adult patients scheduled for laparotomies were analyzed in groups according to the type of reversal (without sugammadex versus 2 or 4 mg/kg sugammadex). There were no changes in our current clinical practice. Blood samples drawn from these patients were standardized at the same time and tested using the same daily calibrated machine. The endpoint was a comparison of the activated partial thromboplastin time (aPTT), prothrombin time (PT), hemoglobin (Hb) level and hematocrit (Ht), immediately before sugammadex administration (H0) and 1 h after neuromuscular block reversal (H1).

RESULTS

One hundred and forty-two patients in three groups were included as follows: 11 in the "without sugammadex" group, 64 in the "2 mg/kg sugammadex" group and 67 in the "4 mg/kg sugammadex" group. Results did not differ significantly among the groups.

CONCLUSIONS

In this prospective observational study, the use of 2 and 4 mg/kg sugammadex was not associated with a longer clotting time or decreased hemoglobin concentrations. Future prospective investigations should study patients receiving 16 mg/kg sugammadex and/or with abnormal coagulation tests.

[Risks acceptability related to obstetrical epidural analgesia]

OBJECTIVES

Evaluation of the acceptability of complications related to obstetrical epidural analgesia in two populations, parturients and anesthesiologists.

STUDY DESIGN

Prospective, transversal, single center study.

MATERIALS AND METHODS

Evaluation of the acceptability of complications associated with obstetric epidural analgesia performed using a questionnaire of six clinical scenarii in two populations: parturients cared at the University maternity of Nancy and anesthesiologists of Lorraine. Patients were interviewed by an anesthesiologist, physicians via Internet. Acceptability was assessed using two tools, the absolute acceptability with a visual analog scale and the relative acceptability obtained by classifying clinical scenario against each other, in ascending order of acceptability.

RESULTS

One hundred and forty-six parturients and 87 anesthetists assessed the acceptability of the different scenarios. The three less serious scenarios (hypotension, failure, dural tap) were acceptable for both populations. One case (spinal hematoma) was unacceptable for parturients. Three cases of varying severity (failure, dural tap, plexus injury with sequelae) were judged significantly less acceptable by patients than physicians (5.9 vs. 7.9 [P<0.001], 5.75 vs. 8.1 [P<0.01], 4.1 vs. 5.1 [P=0.035]). Multivariate analysis did not show any predictive factor of acceptability in both populations.

CONCLUSION

In this study, the overall acceptability of the inherent complications of epidural analgesia was good in the two populations. It was essentially based on the notion of severity and preventability. A large interindividual variability was observed and a better acceptance by the anesthesiologists.

[Prolonged phase II neuromuscular blockade following succinylcholine administration]

Patients who are given a single dose of succinylcholine normally undergo a short-acting depolarizing phase I neuromuscular block but rarely a phase II block. Prolonged neuromuscular blockade occurs after a single dose of succinylcholine in case of genetically determined abnormal plasma butyrylcholinesterase activity. It is mandatory to use monitoring to detect this side effect. We report a case of a patient with abnormal plasma butyrylcholinesterase activity undergoing a six-hour prolonged neuromuscular phase II block, after a single dose of succinylcholine.

Sugammadex: clinical development and practical use

Sugammadex is belonging to a new class of drugs: the selective relaxant binding agents. Sugammadex can reverse residual paralysis by encapsulating free circulating non depolarizing muscle relaxants. The mains advantages of sugammadex when compared with conventional anticholinesterase agents are a much faster recovery time and the unique ability, for the first time, to reverse rapidly and efficiently deep levels of neuromuscular blockade. However it only works for reversal of rocuronium or vecuronium-induced neuromuscular blockade. When administered 3 min after rocuronium the use of a large dose (16 mg/kg) can even reverse rocuronium significantly faster than the spontaneous recovery after succinylcholine.

Acceleromyography to assess neuromuscular recovery: is calibration before measurement mandatory?

BACKGROUND

Acceleromyography has been shown to be an appropriate method in the detection of residual paralysis. However, the clinical importance of an individual calibration of the device in the single patient to improve reliability in detecting residual paralysis remains unclear.

METHODS

Observational study in 100 patients undergoing general anaesthesia with endotracheal intubation and a neuromuscular block with atracurium. In all patients, an individually calibrated acceleromyograph was used to estimate a possible residual block at the end of surgery. Immediately after finishing the calibrated measurements at the end of surgery, a non-calibrated measurement was performed. Agreements between the two measurements were tested using Cohen's κ and a Bland-Altman analysis.

RESULTS

Data from 96 patients were analysed. At the end of surgery, a discordance in the calibrated and the non-calibrated train-of-four ratio was found in 88 patients. Bland-Altman analysis showed a mean (bias) of 0.01, with limits of agreement of 0.15/-0.15. κ was calculated with κ=0.84 for the absence or presence of a potential residual block if defined as a train-of-four ratio of 1.0 as a threshold.

CONCLUSIONS

The results imply a good agreement in the detection of the presence or absence of a residual neuromuscular block between calibrated and non-calibrated acceleromyography if a train-of-four ratio of 1.0 has been chosen as the threshold. However, the estimated train-of-four values are not transferable between calibrated and non-calibrated measurements.