Postoperative Pain and Analgesic Requirements in the First Year after Intraoperative Methadone for Complex Spine and Cardiac Surgery.

BACKGROUND: Methadone is a long-acting opioid that has been reported to reduce postoperative pain scores and analgesic requirements and may attenuate development of chronic postsurgical pain. The aim of this secondary analysis of two previous trials was to follow up with patients who had received a single intraoperative dose of either methadone or traditional opioids for complex spine or cardiac surgical procedures. METHODS: Preplanned analyses of long-term outcomes were conducted for spinal surgery patients randomized to receive 0.2 mg/kg methadone at the start of surgery or 2 mg hydromorphone at surgical closure, and for cardiac surgery patients randomized to receive 0.3 mg/kg methadone or 12 µg/kg fentanyl intraoperatively. A pain questionnaire assessing the weekly frequency (the primary outcome) and intensity of pain was mailed to subjects 1, 3, 6, and 12 months after surgery. Ordinal data were compared with the Mann-Whitney U test, and nominal data were compared using the chi-square test or Fisher exact probability test. The criterion for rejection of the null hypothesis was P < 0.01. RESULTS: Three months after surgery, patients randomized to receive methadone for spine procedures reported the weekly frequency of chronic pain was less (median score 0 on a 0 to 4 scale [less than once a week] vs. 3 [daily] in the hydromorphone group, P = 0.004). Patients randomized to receive methadone for cardiac surgery reported the frequency of postsurgical pain was less at 1 month (median score 0) than it was in patients randomized to receive fentanyl (median score 2 [twice per week], P = 0.004). CONCLUSIONS: Analgesic benefits of a single dose of intraoperative methadone were observed during the first 3 months after spinal surgery (but not at 6 and 12 months), and during the first month after cardiac surgery, when the intensity and frequency of pain were the greatest.

The Effect of an Electronic Dynamic Cognitive Aid Versus a Static Cognitive Aid on the Management of a Simulated Crisis: A Randomized Controlled Trial.

The aim of this study was to assess the effect of a dynamic electronic cognitive aid with embedded clinical decision support (dCA) versus a static cognitive aid (sCA) tool. Anesthesia residents in clinical anesthesia years 2 and 3 were recruited to participate. Each subject was randomized to one of two groups and performed an identical simulated clinical scenario. The primary outcome was task checklist performance with a secondary outcome of performance using the Anesthesia Non-technical skills (ANTS) scoring system. 34 residents were recruited to participate in the study. 19 residents were randomized to the sCA group and 15 to the dCA group. Overall inter-rater agreement for total checklist, malignant hyperthermia, hyperkalemia and ventricular fibrillation was 98.9%, 97.8%, 99.5% and 99.5% respectively with similar Kappa coefficient. Inter-rater agreement for ANTS partial ratings, however, was only 53.5% with a similar Kappa of 0.15. Mean performance was statistically higher in the dCA group versus the sCA group for total check list performance (15.70 ± 1.93 vs 12.95 ± 2.16, p < 0.0001). The difference in performance between dCA and sCA is most notable in dose-dependent related checklist items (4.60 ± 1.3 vs 1.89 ± 1.23, p < 0.0001), while the performance score for dose-independent checklist items was similar between the two groups (p = 0.8908). ANTS ratings did not differ between groups. In conclusion, we evaluated the use of a sCA versus a dCA with embedded decision support in a simulated environment. The dCA group was found to perform more checklist items correctly.Clinical Trial Registration: Clinicaltrials.gov study #: NCT02440607.

Comparison of the TOFscan and the TOF-Watch SX during Recovery of Neuromuscular Function.

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: Quantitative neuromuscular monitoring is required to ensure neuromuscular function has recovered completely at the time of tracheal extubation. The TOFscan (Drager Technologies, Canada) is a new three-dimensional acceleromyography device that measures movement of the thumb in multiple planes. The aim of this observational investigation was to assess the agreement between nonnormalized and normalized train-of-four values obtained with the TOF-Watch SX (Organon, Ireland) and those obtained with the TOFscan during recovery from neuromuscular blockade. METHODS: Twenty-five patients were administered rocuronium, and spontaneous recovery of neuromuscular blockade was allowed to occur. The TOFscan and TOF-Watch SX devices were applied to opposite arms. A preload was applied to the TOF-Watch SX, and calibration was performed before rocuronium administration. Both devices were activated, and train-of-four values were obtained every 15 s. Modified Bland-Altman analyses were conducted to compare train-of-four ratios measured with the TOFscan to those measured with the TOF-Watch SX (when train-of-four thresholds of 0.2 to 1.0 were achieved). RESULTS: Bias and 95% limits of agreement between the TOF-Watch SX and the TOFscan at nonnormalized train-of-four ratios between 0.2 and 1.0 were 0.021 and -0.100 to 0.141, respectively. When train-of-four measures with the TOF-Watch SX were normalized, bias and 95% limits of agreement between the TOF-Watch SX and the TOFscan at ratios between 0.2 and 1.0 were 0.015 and -0.097 to 0.126, respectively. CONCLUSIONS: Good agreement between the TOF-Watch SX with calibration and preload application and the uncalibrated TOFscan was observed throughout all stages of neuromuscular recovery.

Neostigmine Administration after Spontaneous Recovery to a Train-of-Four Ratio of 0.9 to 1.0: A Randomized Controlled Trial of the Effect on Neuromuscular and Clinical Recovery.

BACKGROUND: When a muscle relaxant is administered to facilitate intubation, the benefits of anticholinesterase reversal must be balanced with potential risks. The aim of this double-blinded, randomized noninferiority trial was to evaluate the effect of neostigmine administration on neuromuscular function when given to patients after spontaneous recovery to a train-of-four ratio of 0.9 or greater. METHODS: A total of 120 patients presenting for surgery requiring intubation were given a small dose of rocuronium. At the conclusion of surgery, 90 patients achieving a train-of-four ratio of 0.9 or greater were randomized to receive either neostigmine 40 µg/kg or saline (control). Train-of-four ratios were measured from the time of reversal until postanesthesia care unit admission. Patients were monitored for postextubation adverse respiratory events and assessed for muscle strength. RESULTS: Ninety patients achieved a train-of-four ratio of 0.9 or greater at the time of reversal. Mean train-of-four ratios in the control and neostigmine groups before reversal (1.02 vs. 1.03), 5 min postreversal (1.05 vs. 1.07), and at postanesthesia care unit admission (1.06 vs. 1.08) did not differ. The mean difference and corresponding 95% CI of the latter were -0.018 and -0.046 to 0.010. The incidences of postoperative hypoxemic events and episodes of airway obstruction were similar for the groups. The number of patients with postoperative signs and symptoms of muscle weakness did not differ between groups (except for double vision: 13 in the control group and 2 in the neostigmine group; P = 0.001). CONCLUSIONS: Administration of neostigmine at neuromuscular recovery was not associated with clinical evidence of anticholinesterase-induced muscle weakness. VISUAL ABSTRACT: An online visual overview is available for this article.(Figure is included in full-text article.).

Documentation and Treatment of Intraoperative Hypotension: Electronic Anesthesia Records versus Paper Anesthesia Records.

In this study, we examined anesthetic records before and after the implementation of an electronic anesthetic record documentation (AIMS) in a single surgical population. The purpose of this study was to identify any inconsistencies in anesthetic care based on handwritten documentation (paper) or AIMS. We hypothesized that the type of anesthetic record (paper or AIMS) would lead to differences in the documentation and management of hypotension. Consecutive patients who underwent esophageal surgery between 2009 and 2014 by a single surgeon were eligible for the study. Patients were grouped in to 'paper' or 'AIMS' based on the type of anesthetic record identified in the chart. Pertinent patient identifiers were removed and data collated after collection. Predetermined preoperative and intraoperative data variables were reviewed. Consecutive esophageal surgery patients (N = 189) between 2009 and 2014 were evaluated. 92 patients had an anesthetic record documented on paper and 97 using AIMS. The median number of unique blood pressure recordings was lower in the AIMS group (median (Q1,Q3) AIMS 30.0 (24.0, 39.0) vs. Paper 35.0 (28.5, 43.5), p < 0.01). However, the median number of hypotensive events (HTEs) was higher in the AIMS group (median (Q1,Q3) 8.0 (4.0, 18.0) vs. 4.0 (1.0, 10.5), p < 0.001), and the percentage of HTEs per blood pressure recording was higher in the AIMS group (30.4 ((Q1, Q3) (9.5, 60.9)% vs. 12.5 (2.4, 27.5)%), p < 0.01). Multivariable regression analysis identified independent predictors of HTEs. The incidence of HTEs was found to increase with AIMS (IRR = 1.88, p < 0.01). Preoperative systolic blood pressure, increased blood loss, and phenylephrine. A phenylephrine infusion was negatively associated with hypotensive events (IRR = 0.99, p = 0.03). We noted an increased incidence of HTEs associated with the institution of an AIMS. Despite this increase, no change in medical therapy for hypotension was seen. AIMS did not appear to have an effect on the management of intraoperative hypotension in this patient population.

Clinical Effectiveness and Safety of Intraoperative Methadone in Patients Undergoing Posterior Spinal Fusion Surgery: A Randomized, Double-blinded, Controlled Trial.

BACKGROUND: Patients undergoing spinal fusion surgery often experience severe pain during the first three postoperative days. The aim of this parallel-group randomized trial was to assess the effect of the long-duration opioid methadone on postoperative analgesic requirements, pain scores, and patient satisfaction after complex spine surgery. METHODS: One hundred twenty patients were randomized to receive either methadone 0.2 mg/kg at the start of surgery or hydromorphone 2 mg at surgical closure. Anesthetic care was standardized, and clinicians were blinded to group assignment. The primary outcome was intravenous hydromorphone consumption on postoperative day 1. Pain scores and satisfaction with pain management were measured at postanesthesia care unit admission, 1 and 2 h postadmission, and on the mornings and afternoons of postoperative days 1 to 3. RESULTS: One hundred fifteen patients were included in the analysis. Median hydromorphone use was reduced in the methadone group not only on postoperative day 1 (4.56 vs. 9.90 mg) but also on postoperative days 2 (0.60 vs. 3.15 mg) and 3 (0 vs. 0.4 mg; all P< 0.001). Pain scores at rest, with movement, and with coughing were less in the methadone group at 21 of 27 assessments (all P = 0.001 to < 0.0001). Overall satisfaction with pain management was higher in the methadone group than in the hydromorphone group until the morning of postoperative day 3 (all P = 0.001 to < 0.0001). CONCLUSIONS: Intraoperative methadone administration reduced postoperative opioid requirements, decreased pain scores, and improved patient satisfaction with pain management.

Consent for Anesthesia Clinical Trials on the Day of Surgery: Patient Attitudes and Perceptions.

BACKGROUND: Opportunities for anesthesia research investigators to obtain consent for clinical trials are often restricted to the day of surgery, which may limit the ability of subjects to freely decide about research participation. The aim of this study was to determine whether subjects providing same-day informed consent for anesthesia research are comfortable doing so. METHODS: A 25-question survey was distributed to 200 subjects providing informed consent for one of two low-risk clinical trials. While consent on the day of surgery was permitted for both studies, a preadmission telephone call was required for one. The questionnaire was provided to each subject at the time of discharge from the hospital. The questions were structured to assess six domains relating to the consent process, and each question was graded on a 5-point Likert scale (1 = strongly disagree to 5 = strongly agree). Overall satisfaction with same-day consent was assessed using an 11-point scale with 0 = extremely dissatisfied and 10 = extremely satisfied. RESULTS: Completed questionnaires were received from 129 subjects. Median scores for satisfaction with the consent process were 9.5 to 10. Most respondents reported that the protocol was well explained and comprehended and that the setting in which consent was obtained was appropriate (median score of 5). Most patients strongly disagreed that they were anxious at the time of consent, felt obligated to participate, or had regrets about participation (median score of 1). Ten percent or less of subjects reported negative responses to any of the questions, and no differences were observed between the study groups. CONCLUSION: More than 96% of subjects who provided same-day informed consent for low-risk research were satisfied with the consent process.

Residual Neuromuscular Block in the Elderly: Incidence and Clinical Implications.

BACKGROUND: Elderly patients are at increased risk for anesthesia-related complications. Postoperative residual neuromuscular block (PRNB) in the elderly, defined as a train-of-four ratio less than 0.9, may exacerbate preexisting muscle weakness and respiratory dysfunction. In this investigation, the incidence of PRNB and associated adverse events were assessed in an elderly (70 to 90 yr) and younger cohort (18 to 50 yr). METHODS: Data were prospectively collected on 150 younger and 150 elderly patients. Train-of-four ratios were measured on arrival to the postanesthesia care unit (PACU). After tracheal extubation, patients were examined for adverse respiratory events during transport to the PACU, for 30 min after PACU admission, and during hospital admission. Postoperative muscle weakness was quantified using a standardized examination, and PACU and hospital lengths of stay were determined. RESULTS: The incidence of PRNB was 57.7% in elderly and 30.0% in younger patients (difference, -27.7%; 99% CI, -41.2 to -13.1%; P < 0.001). Airway obstruction, hypoxemic events, signs and symptoms of muscle weakness, postoperative pulmonary complications, and increased PACU and hospital lengths of stay were observed more frequently in the elderly (all P < 0.01). Within each cohort, most adverse events were observed in patients with PRNB. Younger patients with PRNB received larger total doses of rocuronium than did those without it (60 vs. 50 mg, P < 0.01), but there were no differences in rocuronium dose between elderly patients with PRNB and those without it (both 50 mg). CONCLUSION: The elderly are at increased risk for PRNB and associated adverse outcomes.

Does training with human patient simulation translate to improved patient safety and outcome?

PURPOSE OF REVIEW: In this review, we evaluate several articles in an attempt to qualify the effect of human patient simulation in anaesthesia on patient outcome. The recognition of medical error as a significant cause of patient morbidity and mortality has sparked an increased focus on improving healthcare quality and patient safety. Simulation in anaesthesia is a potential tool to help achieve this goal by allowing anaesthesia providers to learn, practice and perfect their craft without a potential harm to patients. It has gained growing traction in the field and is recently a required element in the American Board of Anesthesiology's Maintenance of Certification in Anesthesia programme. RECENT FINDINGS: Very few studies have evaluated the effect of simulation on patient outcome. To date, one study has demonstrated improved individual clinical performance in anaesthesia after simulation training. Research suggests that simulation-based team training can reduce patient mortality and improve the quality of care as measured by surgical quality improvement measures. Simulation may improve healthcare systems by serving as a tool to detect latent error and drive process improvement. SUMMARY: Despite the adoption of simulation, further study is needed to better qualify its effect on patient safety and outcome.

Physiology and biology of neuromuscular transmission in health and disease.

The introduction of powerful and contemporary research techniques has allowed for an increasingly detailed understanding of neuromuscular transmission. The classic model of nerve signaling to muscle using acetylcholine has been well described. Newer discovery points toward a more complex signaling system with adaptive receptor physiology and a multifaceted action response scheme for muscle relaxants. Although adding complexity, these newer discoveries help align experimentally derived knowledge with clinical observations. In this review, new concepts relative to neuromuscular transmission in health and disease are discussed, including a detailed discussion of acetylcholine and acetylcholine receptor physiology. Recent elucidations of the pathophysiologic responses to neuromuscular injury and its clinical implications are also detailed.

Clinical and biologic significance of nuclear unrest in Wilms tumor.

BACKGROUND: Nuclear unrest is a term applied to Wilms tumors (WT) with favorable histology that show nuclear enlargement similar to that seen in anaplasia but with no abnormal mitotic figures. This study was undertaken to evaluate the clinical and pathogenetic significance of WT with nuclear unrest. METHODS: The authors reviewed primary nephrectomy specimens and clinical data from 173 patients who were treated for WT on 1 of 5 consecutive clinical trials at St. Jude Children's Research Hospital. A subset of 70 patients was selected for p53 immunohistochemistry. Seventeen samples of recurrent tumors were also reviewed. RESULTS: WT with nuclear unrest had age and stage distribution similar to that for WT with favorable histology. Patients who had tumors with favorable histology, nuclear unrest, and anaplastic histology had 5-year cumulative incidences of recurrence of 12.2%, 22.2%, and 36.4%, respectively (P = 0.010). Despite the difference in recurrence incidence, patients who had tumors with nuclear unrest and patients who had tumors with favorable histology had nearly identical overall survival. Immunostaining for p53 was positive in 2 of 24 tumors (8.3%) with favorable histology, 1 of 25 tumors (4%) with nuclear unrest, and 16 of 21 tumors (76%) with anaplastic histology (P < 0.001). Histologic review of samples from recurrent tumors showed that 7 of 10 of primary tumors converted from favorable histology to either nuclear unrest or anaplastic histology in the recurrent tumor. CONCLUSIONS: WT with nuclear unrest more closely resembles favorable histology than anaplastic histology, both clinically and pathogenetically. Analysis of samples from recurrent tumors suggests that WT with nuclear unrest represents an intermediary in the continuum from favorable histology to anaplastic histology. For treatment stratification, it is appropriate to continue grouping nuclear unrest with favorable histology, although a larger analysis will be necessary to confirm the current findings.