Is the Bland-Altman plot method useful without inferences for accuracy, precision, and agreement?

OBJECTIVE: This study aims to propose a comprehensive alternative to the Bland-Altman plot method, addressing its limitations and providing a statistical framework for evaluating the equivalences of measurement techniques. This involves introducing an innovative three-step approach for assessing accuracy, precision, and agreement between techniques, which enhances objectivity in equivalence assessment. Additionally, the development of an R package that is easy to use enables researchers to efficiently analyze and interpret technique equivalences. METHODS: Inferential statistics support for equivalence between measurement techniques was proposed in three nested tests. These were based on structural regressions with the goal to assess the equivalence of structural means (accuracy), the equivalence of structural variances (precision), and concordance with the structural bisector line (agreement in measurements obtained from the same subject), using analytical methods and robust approach by bootstrapping. To promote better understanding, graphical outputs following Bland and Altman's principles were also implemented. RESULTS: The performance of this method was shown and confronted by five data sets from previously published articles that used Bland and Altman's method. One case demonstrated strict equivalence, three cases showed partial equivalence, and one showed poor equivalence. The developed R package containing open codes and data are available for free and with installation instructions at Harvard Dataverse at https://doi.org/10.7910/DVN/AGJPZH. CONCLUSION: Although easy to communicate, the widely cited and applied Bland and Altman plot method is often misinterpreted, since it lacks suitable inferential statistical support. Common alternatives, such as Pearson's correlation or ordinal least-square linear regression, also fail to locate the weakness of each measurement technique. It may be possible to test whether two techniques have full equivalence by preserving graphical communication, in accordance with Bland and Altman's principles, but also adding robust and suitable inferential statistics. Decomposing equivalence into three features (accuracy, precision, and agreement) helps to locate the sources of the problem when fixing a new technique.

Is the Bland-Altman plot method useful without inferences for accuracy, precision, and agreement?

ABSTRACT OBJECTIVE This study aims to propose a comprehensive alternative to the Bland-Altman plot method, addressing its limitations and providing a statistical framework for evaluating the equivalences of measurement techniques. This involves introducing an innovative three-step approach for assessing accuracy, precision, and agreement between techniques, which enhances objectivity in equivalence assessment. Additionally, the development of an R package that is easy to use enables researchers to efficiently analyze and interpret technique equivalences. METHODS Inferential statistics support for equivalence between measurement techniques was proposed in three nested tests. These were based on structural regressions with the goal to assess the equivalence of structural means (accuracy), the equivalence of structural variances (precision), and concordance with the structural bisector line (agreement in measurements obtained from the same subject), using analytical methods and robust approach by bootstrapping. To promote better understanding, graphical outputs following Bland and Altman's principles were also implemented. RESULTS The performance of this method was shown and confronted by five data sets from previously published articles that used Bland and Altman's method. One case demonstrated strict equivalence, three cases showed partial equivalence, and one showed poor equivalence. The developed R package containing open codes and data are available for free and with installation instructions at Harvard Dataverse at https://doi.org/10.7910/DVN/AGJPZH. CONCLUSION Although easy to communicate, the widely cited and applied Bland and Altman plot method is often misinterpreted, since it lacks suitable inferential statistical support. Common alternatives, such as Pearson's correlation or ordinal least-square linear regression, also fail to locate the weakness of each measurement technique. It may be possible to test whether two techniques have full equivalence by preserving graphical communication, in accordance with Bland and Altman's principles, but also adding robust and suitable inferential statistics. Decomposing equivalence into three features (accuracy, precision, and agreement) helps to locate the sources of the problem when fixing a new technique.

Decreasing inconsistent alarms notifications: a pragmatic clinical trial in a post-anesthesia care unit.

BACKGROUND: Alarms alert healthcare professionals of deviations from normal/physiologic status. However, alarm fatigue may occur when their high pitch and diversity overwhelm clinicians, possibly leading to alarms being disabled, paused, and/or ignored. We aimed to determine whether a staff educational program on customizing alarm settings of bedside monitors may decrease inconsistent alarms in the Post-Anesthesia Care Unit (PACU). METHODS: This is a prospective, analytic, quantitative, pragmatic, open-label, single-arm study. The outcome was evaluated on PACU admission before (P1) and after (P2) the implementation of the educational program. The heart rate, blood pressure, and oxygen saturation alarms were selected for clinical consistency. RESULTS: A total of 260 patients were included and 344 clinical alarms collected, with 270 (78.4%) before (P1), and 74 (21.6%) after (P2) the intervention. Among the 270 alarms in P1, 45.2% were inconsistent (i.e., false alarms), compared to 9.4% of the 74 in P2. Patients with consistent alarms occurred in 30% in the P1 and 27% in the P2 (p = 0.08). Patients with inconsistent alarms occurred in 25.4% in the P1 and in 3.8% in the P2. Ignored consistent alarms were reduced from 21.5% to 2.6% (p = 0.004) in the P2 group. The educational program was a protective factor for the inconsistent clinical alarm (OR = 0.11 [95% CI 0.04-0.3]; p < 0.001) after adjustments for age, gender, and ASA physical status. CONCLUSION: Customizing alarm settings on PACU admission proved to be a protective factor against inconsistent alarm notifications of multiparametric monitors.

Ensino da anatomia: dissecção em associação com a tecnologia no curso de Medicina / Teaching anatomy: dissection in association with technology in the Medical course

Resumo: Introdução: Um estudo de 2010 apontou as necessidades futuras da educação médica, com conteúdos e práticas integrados, fomentada pela tecnologia educacional virtual e pela prioridade na competência, não no tempo. A anatomia, indistinta de outros fundamentos da medicina, enfrenta restrições à dissecção de cadáveres. Objetivo: Ensaio sobre o ensino da anatomia em contextos clínicos e com emprego de tecnologias. Método: Utilizaram-se a plataforma PubMed da National Library of Medicine e os descritores ((anatomy [MeSH Terms]) AND (method, teaching [MeSH Terms])) AND (surgery [MeSH Terms]). Resultado: Há indicação de 316 artigos no período 2000-2022 (junho de 2022). A principal pergunta sobre o ensino de anatomia refere-se à substituição da técnica de dissecção e, por consequência, do uso do cadáver. Estudos sugerem a manutenção do uso da dissecção, da prossecção e de maior uso de meios digitais e modelares. Conclusão: O material cadavérico deve ser garantido com maior uso da prossecção, com a dissecção sendo dirigida ou eletiva. Realidade virtual e material de prossecção devem ser assimilados como instrumentais e supervisionados por anatomistas qualificados e enriquecidos pela interpretação e aplicabilidade clínica.

Abstract: Introduction: A 2010 study pointed out the future needs of medical education, with integrated contents and practices, fostered by virtual educational technology and by prioritizing competence, not time. Anatomy, indistinguishable from other fundamentals of medicine, faces restrictions on cadaver dissection. Objective: Essay on the teaching of anatomy in clinical contexts and the use of technologies Method: The "pubmed" platform of the National Library of Medicine and descriptors ((anatomy[MeSH Terms]) AND (method, teaching[MeSH Terms])) AND (surgery[MeSH Terms]) were used. Result: There are indications of 316 articles in the period 2000-2022 (June 2022). The main question about the teaching of Anatomy is the replacement of the dissection technique and, consequently, the use of the cadaver. Studies suggest maintaining the use of dissection, prosection and greater use of digital and model means. Conclusion: Cadaveric material should be secured with greater use of prosection and dissection being directed or elective. Virtual reality and permanent material must be assimilated as instrumental and supervised by qualified anatomists and enriched by interpretation and clinical applicability.

An evaluation of the accuracy and self-reported confidence of clinicians in using the ASA-PS Classification System.

OBJECTIVES: The American Society of Anesthesiologists Physical Status (ASA-PS) is a grading system routinely adopted worldwide by physicians to classify patients' overall health status. Concerns have been raised surrounding the subjectiveness of this system, potentially leading to poor inter-rater agreement/reliability. We hypothesized that physicians are overconfident when assigning ASA-PS scores and that presenting them with the ASA-PS definitions/examples would improve accuracy. We therefore evaluated participants' accuracy and self-reported confidence on the ASA-PS Classification System (1) while assigning ASA-PS according to their baseline knowledge/judgment; and (2) after a single exposure to the ASA-PS definitions/examples. DESIGN: Prospective before-and-after web-based study. PARTICIPANTS: 272 anesthesiologists and 114 non-anesthesiologists. INTERVENTIONS: Participants voluntarily answered a web-based questionnaire consisting of 10 hypothetical cases. They were asked to assign an ASA-PS score and rate their perceived self-confidence level (20-100%) on the accuracy of their assigned score for each case both (1) before and (2) after reviewing the ASA-PS definitions/examples. The correct ASA-PS for each hypothetical case was determined by consensus among investigators. MEASUREMENTS: Participants' accuracy, self-reported confidence, and calibration of confidence on the application of ASA-PS Classification System. Agreement between measures was tested using kappa coefficient. RESULTS: Anesthesiologists had better accuracy than non-anesthesiologists both on initial [6(5-7) vs. 4(3-5) out of 10; p < 0.001] as well as subsequent [7(6-8) vs. 6(4-7); p < 0.001] ASA-PS score assignments. Participants' self-reported confidence was greater than their accuracy for assigned ASA-PS scores (p < 0.001). ASA-PS agreement between anesthesiologists and non-anesthesiologists was poor (κ < 0.20). Participants' accuracy for hypothetical cases of ASA-PS I, II, and III involving adult patients was overall greater than for ASA-PS IV, V, and III (the latter involving a neonate) for both anesthesiologists and non-anesthesiologists (p < 0.001). CONCLUSIONS: Physicians tend to disagree and be overconfident when assigning ASA-PS scores. A brief consultation of the ASA-PS definitions/examples improves the accuracy for both anesthesiologists and non-anesthesiologists.

Comparison of digital games as a cognitive function assessment tool for current standardized neuropsychological tests.

OBJECTIVE: Cognitive dysfunction may occur postoperatively. Fast and efficient assessment of Postoperative Cognitive Dysfunction (POCD) can minimize loss of quality of life, and therefore, a study comparing a digital game with standard neuropsychological tests to assess executive, mnemonic, and attention functions to evaluate POCD seems to be relevant both for research and clinical practice. METHODS: A battery of standardized tests and a digital game (MentalPlus®) were administered to 60 patients at the Central Institute of Hospital das Clínicas in São Paulo (36 women and 24 men), with ages between 29 and 82 years, pre- and post-surgery performed under anesthesia. Correlation and linear regression model were used to compare the scores obtained from the standardized tests to the scores of the six executive and cognitive functions evaluated by the game (short- and long-term memory, selective and alternating attention, inhibitory control, and visual perception). RESULTS: After correlation analysis, a statistically significant result was found mainly for the correlation between the scores from the phase of the digital game assessing the visuoperception function and the scores from the A and B cards of the Stroop Test (p < 0.001, r = 0.99 and r = 0.64, respectively), and the scores from TMTA (p = 0.0046, r = 0.51). We also found a moderate correlation between the phase of the game assessing short-memory function and VVLT (p < 0.001, r = 0.41). No statistically significant correlations were found for the other functions assessed. CONCLUSION: The digital game provided scores in agreement with standardized tests for evaluating visual perception and possibly short-term memory cognitive functions. Further studies are necessary to verify the correlation of other phases of the digital game with standardized tests assessing cognitive functions.

Assessment of a digital game as a neuropsychological test for postoperative cognitive dysfunction.

OBJECTIVE: Postoperative cognitive dysfunction may result from worsening in a condition of previous impairment. It causes greater difficulty in recovery, longer hospital stays, and consequent delay in returning to work activities. Digital games have a potential neuromodulatory and rehabilitation effect. In this study, a digital game was used as a neuropsychological test to assess postoperative cognitive dysfunction, with preoperative patient performance as control. METHODS: It was a non-controlled study, with patients selected among candidates for elective non-cardiac surgery, evaluated in the pre- and postoperative periods. The digital game used has six phases developed to evaluate selective attention, alternating attention, visuoperception, inhibitory control, short-term memory, and long-term memory. The digital game takes about 25 minutes. Scores are the sum of correct answers in each cognitive domain. Statistical analysis compared these cognitive functions pre- and post-surgery using a generalized linear mixed model (ANCOVA). RESULTS: Sixty patients were evaluated, 40% male and 60% female, with a mean age of 52.7 ± 13.5 years. Except for visuoperception, a reduction in post-surgery scores was found in all phases of the digital game. CONCLUSION: The digital game was able to detect decline in several cognitive functions postoperatively. As its completion is faster than in conventional tests on paper, this digital game may be a potentially recommended tool for assessing patients, especially the elderly and in the early postoperative period.

Ultrasound-guided peripheral abdominal wall blocks.

The practice of regional anesthesia is in a state of progressive evolution, mainly due to the advent of ultrasound as an anesthesiologist's instrument. Alternative techniques for postoperative analgesia of abdominal surgeries, such as transversus abdominis plane block, oblique subcostal transversus abdominis plane block, rectus abdominis muscle sheath block, ilioinguinal and iliohypogastric nerve block, and quadratus lumborum plane block, have proven useful, with good analgesic efficacy, especially when neuroaxial techniques (spinal anesthesia or epidural anesthesia) are not possible. This review discusses such blockades in detail, including the anatomical principles, indications, techniques, and potential complications.

Continuous peripheral nerve block for in-patients with lower limb ischemic pain.

OBJECTIVES: Demonstrate that continuous peripheral nerve block (CPNB) may be an alternative with adequate analgesia and a lower incidence of side effects for ischemic pain due peripheral obstructive arterial disease (POAD). METHODS: Retrospective cohort study with 21 patients with POAD, Fontaine IV graded, with foot pain. Patients were submitted to continuous sciatic nerve block (CSNB), through a perineural catheter. Primary outcomes were pain intensity (by numerical rating scale) and opioid consumption (in oral morphine equivalents). RESULTS: During CSNB, pain scores markedly decreased in comparison to the pre-block period. CONCLUSIONS: CPNB may be a good option for ischemic pain treatment in in-patients, as it provides effective pain control with fewer adverse effects.

Ultrasound-guided peripheral abdominal wall blocks

The practice of regional anesthesia is in a state of progressive evolution, mainly due to the advent of ultrasound as an anesthesiologist's instrument. Alternative techniques for postoperative analgesia of abdominal surgeries, such as transversus abdominis plane block, oblique subcostal transversus abdominis plane block, rectus abdominis muscle sheath block, ilioinguinal and iliohypogastric nerve block, and quadratus lumborum plane block, have proven useful, with good analgesic efficacy, especially when neuroaxial techniques (spinal anesthesia or epidural anesthesia) are not possible. This review discusses such blockades in detail, including the anatomical principles, indications, techniques, and potential complications.

Intraoperative pulmonary hyperdistention estimated by transthoracic lung ultrasound: A pilot study.

INTRODUCTION: Transthoracic lung ultrasound can assess atelectasis reversal and is considered as unable to detect associated hyperdistention. In this study, we describe an ultrasound pattern highly suggestive of pulmonary hyperdistention. METHODS: Eighteen patients with normal lungs undergoing lower abdominal surgery were studied. Electrical impedance tomography was calibrated, followed by anaesthetic induction, intubation and mechanical ventilation. To reverse posterior atelectasis, a recruitment manoeuvre was performed. Positive-end expiratory pressure (PEEP) titration was then obtained during a descending trial - 20, 18, 16, 14, 12, 10, 8, 6 and 4cmH2O. Ultrasound and electrical impedance tomography data were collected at each PEEP level and interpreted by two independent observers. Spearman correlation test and receiving operating characteristic curve were used to compare lung ultrasound and electrical impedance tomography data. RESULTS: The number of horizontal A lines increased linearly with PEEP: from 3 (0, 5) at PEEP 4cmH2O to 10 (8, 13) at PEEP 20cmH2O. The increase number of A lines was associated with a parallel and significant decrease in intercostal space thickness (p=0.001). The lung ultrasound threshold for detecting pulmonary hyperdistention was defined as the number of A lines counted at the PEEP preceding the PEEP providing the best respiratory compliance. Six A lines was the median threshold for detecting pulmonary hyperdistention. The area under the receiving operating characteristic curve was 0.947. CONCLUSIONS: Intraoperative transthoracic lung ultrasound can detect lung hyperdistention during a PEEP descending trial. Six or more A lines detected in normally aerated regions can be considered as indicating lung hyperdistention. TRIAL REGISTRATION: NCT02314845 Registered on ClinicalTrials.gov.

Aprepitant plus palonosetron for the prevention of postoperative nausea and vomiting after breast cancer surgery: a double blind, randomized trial.

OBJECTIVES: To evaluate the addition of a fourth antiemetic intervention in patients at high risk for postoperative nausea and vomiting (PONV). METHODS: High-risk patients (Apfel score 3 or 4) scheduled for unilateral mastectomy were randomly allocated in one of two groups, oral aprepitant (oral aprepitant 80 mg, intravenous dexamethasone 8 mg, and palonosetron 0.075 mg) and oral placebo (oral placebo, intravenous dexamethasone 4 mg, and palonosetron 0.075 mg). Patients and caregivers were blinded to the group assignments. The primary efficacy endpoints included the incidence of nausea and vomiting, and the secondary endpoints included use of rescue antiemetics during a 48-hour postoperative period. ClinicalTrials.gov: NCT02431286. RESULTS: One hundred patients were enrolled in this study and 91 were analyzed, 48 in group A and 43 in group P. No patient presented with nausea or vomiting in the first 2 hours after surgery. From the 2nd to the 6th hour, the incidence of PONV was 8.33% in group A and 9.30% in group P. In the first 24 hours, the incidence of PONV was 27.08% in the group A and 20.93% in group P. From the 24th to the 48th hour, the incidence of PONV was 8.33% in group A and 13.95% in group P. There were no statistically significant differences in PONV between groups. CONCLUSION: The addition of aprepitant as a third antiemetic resulted in no significant reduction in the incidence of PONV in this population. However, the incidence of PONV was reduced in relation to the general population.

Aprepitant plus palonosetron for the prevention of postoperative nausea and vomiting after breast cancer surgery: a double blind, randomized trial

OBJECTIVES: To evaluate the addition of a fourth antiemetic intervention in patients at high risk for postoperative nausea and vomiting (PONV). METHODS: High-risk patients (Apfel score 3 or 4) scheduled for unilateral mastectomy were randomly allocated in one of two groups, oral aprepitant (oral aprepitant 80 mg, intravenous dexamethasone 8 mg, and palonosetron 0.075 mg) and oral placebo (oral placebo, intravenous dexamethasone 4 mg, and palonosetron 0.075 mg). Patients and caregivers were blinded to the group assignments. The primary efficacy endpoints included the incidence of nausea and vomiting, and the secondary endpoints included use of rescue antiemetics during a 48-hour postoperative period. ClinicalTrials.gov: NCT02431286. RESULTS: One hundred patients were enrolled in this study and 91 were analyzed, 48 in group A and 43 in group P. No patient presented with nausea or vomiting in the first 2 hours after surgery. From the 2nd to the 6th hour, the incidence of PONV was 8.33% in group A and 9.30% in group P. In the first 24 hours, the incidence of PONV was 27.08% in the group A and 20.93% in group P. From the 24th to the 48th hour, the incidence of PONV was 8.33% in group A and 13.95% in group P. There were no statistically significant differences in PONV between groups. CONCLUSION: The addition of aprepitant as a third antiemetic resulted in no significant reduction in the incidence of PONV in this population. However, the incidence of PONV was reduced in relation to the general population.

Failure of reversion of neuromuscular block with sugammadex in patient with myasthenia gravis: case report and brief review of literature.

BACKGROUND: Myasthenia gravis (MG) is a challenge for anesthesia management. This report shows that the use of rocuronium-sugammadex is not free from flaws and highlights the importance of cholinesterase inhibitors management and neuromuscular block monitoring in the perioperative period of myasthenic patients. CASE PRESENTATION: Myasthenic female patient submitted to general balanced anesthesia using 25 mg of rocuronium. Under train-of-four (TOF) monitoring, repeated doses of sugammadex was used in a total of 800 mg without recovery of neuromuscular blockade, but TOF ratio (TOFR) was stabilized at 60%. Neostigmine administration led to the improvement of TOFR. CONCLUSIONS: Although the use of rocuronium-sugammadex seems safe, we should consider their unpredictability in myasthenic patients. This report supports the monitoring of neuromuscular blockade as mandatory in every patient, especially the myasthenic ones.

Intraoperative use of methadone improves control of postoperative pain in morbidly obese patients: a randomized controlled study.

OBJECTIVES: Surgical patients still commonly experience postoperative pain. With the increasing prevalence of obesity, there is a growing demand for surgical procedures by this population. Intraoperative use of methadone has not been well assessed in this population. MATERIALS AND METHODS: Patients with a body mass index of 35 kg/m2 or more undergoing bariatric surgery were randomly assigned to receive either fentanyl (group F) or methadone (group M) in anesthesia induction and maintenance. The primary outcome was morphine consumption during the first 24 hours after surgery through a patient-controlled analgesia device. Secondary outcomes were pain scores at rest and while coughing, opioid related side effects, and patient satisfaction. The patients were also evaluated 3 months after surgery for the presence of pain, dysesthesia, or paresthesia at surgical site. RESULTS: Postoperative morphine consumption was significantly higher for patients receiving fentanyl than methadone during the postoperative period at 2 hours (mean difference [MD] 6.4 mg; 95% CI 3.1-9.6; P<0.001), 2-6 hours (MD 11.4 mg; 95% CI 6.5-16.2; P<0.001), 6-24 hours (MD 10.4 mg; 95% CI 5.0-15.7; P<0.001), and 24-48 hours (MD 14.5 mg; 95% CI 3.9-25.1; P=0.01). Patients from group F had higher pain scores until 24 hours postoperatively, higher incidence of nausea and vomiting, lower satisfaction, and more evoked pain at surgical scar at the 3-month postoperative evaluation than group M. CONCLUSION: Intraoperative methadone can safely lower postoperative opioid consumption and improve postoperative pain scores compared with fentanyl in morbidly obese patients.

Continuous femoral nerve blockade and single-shot sciatic nerve block promotes better analgesia and lower bleeding for total knee arthroplasty compared to intrathecal morphine: a randomized trial.

BACKGROUND: Knee arthroplasty leads to postoperative pain. This study compares analgesia and postoperative bleeding achieved by intrathecal morphine with a continuous femoral plus single-shot sciatic nerve block. METHODS: A randomized non-blinded clinical trial enrolled patients aged over 18 years old, ASA I to III who underwent total knee arthroplasty. All patients underwent spinal anesthesia with isobaric bupivacaine, 20 mg. One group received 100 mcg of intrathecal morphine (M group), and the other received a femoral nerve block by continuous infusion plus a "single shot" block of the sciatic nerve at the end of the surgery (FI group). Pain score from verbal numeric rating scale (VNRS) and morphine consumption during the first 72 h, as well as motor blockade, adverse effects, and postoperative bleeding were recorded. Analysis of variance of repeated measures with Bonferroni post-test, t-test and Fisher exact test were used for statistical analysis. RESULTS: Thirty nine patients completed the study (M = 20; FI = 19 patients) and were similar except for higher age in the FI group. Motor blockade as well as movement pain during postanesthesia care unit (PACU) staying were not different between the groups, but movement pain was significantly lower in FI group after 24 h. Postoperative bleeding (ml) was lower in FI group. CONCLUSIONS: Continuous femoral nerve block combined with sciatic nerve block provides effective for postoperative analgesia in patients undergoing total knee arthroplasty, with lower pain scores after 24 h and a lower incidence of adverse effects and bleeding compared to intrathecal morphine. TRIAL REGISTRATION: Retrospectively registered on https://clinicaltrials.gov/ under identifier NCT02882152 , 23rd December, 2016.

Sugammadex ED90 dose to reverse the rocuronium neuromuscular blockade in obese patients.

Objective: to determine the ED90 (minimum effective dose in 90% of patients) of sugammadex for the reversal of rocuronium-induced moderate neuromuscular blockade (NMB) in patients with grade III obesity undergoing bariatric surgery. Methods: we conducted a prospective study with the biased coin up-and-down sequential design. We chosen the following doses: 2.0mg/Kg, 2.2mg/Kg, 2.4mg/Kg, 2.6mg/Kg, 2.8mg/Kg. The complete reversal of rocuronium-induced NMB considered a T4/T1 ratio ≥0.9 as measured by TOF. After induction of general anesthesia and calibration of the peripheral nerve stimulator and accelerometer, we injected rocuronium 0.6mg/kg. We administered propofol and remifentanil by continuous infusion, and intermittent boluses of rocuronium throughout the procedure. Results: we evaluated 31 patients, of whom 26 had displayed successful reversal of the NMB with sugammadex, and failure in five. The mean time to complete moderate NMB reversal was 213 seconds (172-300, median 25-75%). The ED90 of sugammadex calculated by regression was 2.39mg/kg, with a 95% confidence interval of 2.27-2.46 mg/kg. Conclusion: the ED90 of sugammadex in patients with grade III obesity or higher was 2.39mg/kg.

Objetivos: determinar a ED90 (dose mínima eficaz em 90% dos pacientes) de sugamadex para a reversão de bloqueio neuromuscular (BNM) moderado induzido pelo rocurônio em pacientes com obesidade grau III submetidos à cirurgia bariátrica. Métodos: estudo prospectivo com o método de projeção sequencial para cima e para baixo da moeda enviesada. As seguintes doses foram escolhidas: 2,0mg/kg-1, 2,2mg/kg-1, 2,4mg/kg-1, 2,6mg/kg-1, 2,8mg/kg-1. A reversão completa de BNM induzido por rocurônio considerou uma relação T4/T1 ≥0,9 na medida do TOF. Após a indução da anestesia geral e calibração do estimulador de nervo periférico e acelerômetro, rocurônio 0,6mg/kg-1 foi injetado. Infusão contínua de propofol e remifentanil, e bolus intermitente de rocurônio foram injetados durante todo o procedimento. Resultados: trinta e um pacientes foram avaliados, 26 dos quais bem-sucedidos e cinco sem reversão completa do BNM moderado promovido pelo sugamadex. O tempo médio para completar reversão de BNM foi 213 segundos (172 a 300 segundos; mediana, 25-75%). O ED90 de sugamadex calculado pela regressão foi de 2,39mg/kg-1 com um intervalo de confiança de 95% (2,27 a 2,46mg/kg-1). Conclusão: o ED90 de sugamadex em pacientes com obesidade grau III ou superior foi 2,39mg/kg-1.