Canadian Journal of Anesthesia-Journal Canadien D Anesthesie最新文献

Purpose: Owing in part to the development and popularization of fascial plane blocks (FPBs), high-volume injection of local anesthetic (LA) is becoming more commonplace. Fascial plane blocks typically use high LA volumes to maximize spread, often pushing towards the maximum recommended dosing. This narrative review summarizes the pharmacokinetic literature for several of the most common FPBs.

Methods: We searched PubMed®, Embase, the Cochrane Library, and Google Scholar using the following search terms: (plasma concentration, pharmacokinetics, toxicity, local anesthetic systemic toxicity [LAST]) AND (erector spinae plane, serratus anterior plane, parasternal intercostal plane, quadratus lumborum, transversus abdominis plane, fascia iliaca, pericapsular nerve group), as well as FPB acronyms.

Results: Typical LA dosing in studies used concentrations of ropivacaine 0.25-0.5%, levobupivacaine 0.125-0.25%, and bupivacaine 0.25% at volumes of 20-40 mL. While numerous studies found average LA plasma concentrations well below the established thresholds, several patients crossed the toxic threshold. Patients with LA plasma concentrations above toxic thresholds often did not experience LAST symptoms; nevertheless, there are several reports of mild neurologic symptoms and even seizures.

Conclusions: Diligent care should be taken to avoid LAST in FPBs. We recommend the calculation of weight-based doses, aspiration before injection, incremental dosing, close monitoring, and ultrasound observation of injectate when administering high volumes. Clinicians should consider adding low-dose epinephrine to FPBs. The LA concentration should decrease with increasing volume to ensure that the total dose of LA remains below maximum dosing recommendations. Clinicians should use extra caution in those blocks and with patients at a higher risk for LAST.

Purpose: Epidural analgesia has been considered a highly effective analgesic modality for hepatobiliary surgeries, particularly within 72 hr postoperatively. Coagulation derangements are possible complications following liver resection that can be concerning in the setting of epidural analgesia given the inherent risk of spinal epidural hematoma. We sought to develop predictive models for postoperative coagulation disturbance (defined as an international normalized ratio > 1.5, a partial thromboplastin time > 40 sec, or a platelet count < 100,000 × 10⁶·L^-1) in patients eligible for epidural analgesia.

Methods: We conducted a retrospective cohort study of patients undergoing liver resection at the University of Iowa (Iowa City, IA, USA) between 2011 and 2023. We reviewed records for patient characteristics, operative parameters, preoperative coagulation labs, and postoperative coagulation labs up to seven postoperative days. We used three types of predictive modeling.

Results: Among 684 patients, 37 had a length of stay ≤ 72 hr of surgery or preoperative coagulation disturbance. Among the remaining 647 patients, 512 (79%) received a thoracic epidural. The incidence of postoperative coagulation disturbances within 72 hr was 25% (95% confidence interval, 22 to 28), mostly thrombocytopenia (20% of all patients), and was noted on postoperative day 1 for 11% and postoperative day 2 for 22%. The volume of liver resected was greater among patients with postoperative coagulation disturbance (P < 0.001; area under the receiving operating characteristic curve, 0.61). There was no predictive value for coagulation disturbance based on patients' sex, American Society of Anesthesiologists' Physical Status classification, body mass index, weight, age, adjuvant chemotherapy, estimated operative duration, or year of data (all standardized differences < 0.24). Classification tree modeling had a single node (i.e., no useful preoperative prediction). Stepwise backward logistic regression using P < 0.05 for inclusion had just two patients (0.3%) with a predicted probability of postoperative coagulation disturbance < 10% and none < 5%.

Conclusions: Coagulation disturbances occur commonly in the context of hepatic surgery. Preoperative data commonly used to qualify a patient to receive epidural analgesia are insufficient to predict which patients are likely to develop postoperative coagulation disturbance. Regardless of the predictive modeling or criterion, the postoperative risk of coagulopathic disturbance will exceed 5% by 72 hr postoperatively. Enhanced recovery protocols recommending early epidural catheter removal need to consider the period of incidence of coagulation disturbance.

Purpose: The association between postoperative body temperature and in-hospital mortality remains unclear. We sought to evaluate this association across all surgical patients and assessed whether it is affected by the indication for surgery (i.e., surgical source control of infection vs other indications).

Methods: In a nationwide cohort study, we included critically ill adult patients registered in the Japanese Intensive Care Patient Database who underwent surgery between 2015 and 2021. We evaluated whether the body temperature was associated with in-hospital mortality, and if a differential effect was observed in patients who underwent surgery for source control of infection vs other indications (control group). We categorized the highest body temperatures recorded in the 24 hr after admission following surgery in 0.5-°C intervals and evaluated them using multivariable regression. We conducted a subgroup analysis of patients who underwent surgery for infection control vs other indications. We report the summary estimates using adjusted odds ratios (ORs) and 95% confidence intervals (CIs). We examined the association between body temperature category and in-hospital mortality using cubic spline models to assess nonlinear associations.

Results: Among 157,028 patients, the overall in-hospital mortality was 2.9%. We observed a U-shaped association of temperature and mortality, with increased mortality at body temperatures < 36.0 °C (OR, 2.15; 95% CI, 1.62 to 2.86) and > 40.0 °C (OR, 1.41; 95% CI, 1.02 to 1.96). We observed the lowest mortality at 37.5-37.9 °C (OR, 0.62; 95% CI, 0.55 to 0.70). Low body temperatures were associated with increased mortality regardless of the presence or absence of infection, while high body temperatures were not associated with increased mortality in patients undergoing surgery for source control of infection.

Conclusions: In this large nationwide cohort of critically ill surgical patients in Japan, we observed that low and high postoperative body temperatures were associated with increased in-hospital mortality. Nevertheless, we did not observe the association with high body temperature and increased mortality in the subgroup of patients having undergone surgery for infection control.

Purpose: Emerging evidence suggests that 3,4-methylenedioxymethamphetamine (MDMA)-assisted psychotherapy may be a promising intervention for chronic pain. We designed the Ecstasy for Alleviating Severe Chronic Neuropathic Pain (EASE-Pain) trial, a randomized controlled trial comparing MDMA with an active placebo (methylphenidate) for pain relief. We sought to conduct a prospective preference assessment (PPA) prior to the trial, with the objectives to 1) assess willingness to participate in the trial, 2) identify participants' motivations and concerns to enhance enrolment and acceptability, and 3) compare demographic and health characteristics between willing and nonwilling participants.

Methods: We recruited patients from the St. Michael's Hospital Pain Clinic (Toronto, ON, Canada) from July to August 2024. Each participant completed four PPA phases: 1) a trial description, 2) comprehension assessment, 3) open-ended questions exploring attitudes towards the trial, and 4) a self-administered questionnaire. We analyzed data qualitatively using thematic analysis and quantitatively using t tests and Fisher's exact test.

Results: We enrolled 42 patients, with 76% willing and 24% not willing to participate in the EASE-Pain trial. White/European participants were more likely to be willing than not willing to participate (78% vs 40%; P < 0.001). Motivating factors for participation included pain relief (62%) and seeking alternatives to ineffective treatments (26%). Common concerns included side effects (43%), impacts on comorbidities (19%), and the stigma of MDMA (19%).

Conclusions: The results of this study indicate a strong willingness among patients with chronic pain to participate in the EASE-Pain trial. Primary concerns included side effects and impacts on comorbidities. In response, protocol modifications, including improved patient education on study drug effects, will be implemented.

Purpose: We aimed to investigate the impact that patient-initiated beta-blocker interruption on the morning of surgery has on postoperative adverse outcomes.

Methods: We conducted a historical cohort study of consecutive patients undergoing elective surgical procedures at two hospitals belonging to a single academic institution from 2014 to 2018 in the Canadian province of Ontario. We used electronic medical records to identify the initial cohort and collect patient information, including medication interruption. These data were linked to administrative data holdings, which we used to capture study outcomes, including 30-day and 90-day mortality and a composite outcome representing several adverse events. We used logistic regression to evaluate between-group differences in study outcomes and included a covariate representing propensity for beta-blocker interruption.

Results: The final cohort included 4,971 patients, 22.2% of whom experienced a preoperative beta-blocker interruption. As compared with patients who continued their medication, those with a beta-blocker interruption had significantly decreased odds of 30-day mortality (odds ratio [OR], 0.42; 95% confidence interval [CI], 0.18 to 1.00; P = 0.049) and 90-day mortality (OR, 0.51; 95% CI, 0.28 to 0.90; P = 0.02) in adjusted analyses. Following adjustment, beta-blocker interruption was not significantly associated with any of the secondary outcomes.

Conclusions: Results from this study suggest that preoperative acute beta-blocker interruption is significantly associated with decreased 30-day and 90-day postoperative all-cause mortality. These data challenge the long-held assumption that patients on beta-blockers should continue these medications during the perioperative period and indicate that a proper controlled trial is needed to assess the impact of withholding beta-blockers prior to major surgery.