Background: Evidence-based international expert consensus regarding anaesthetic practice in hip/knee arthroplasty surgery is needed for improved healthcare outcomes. Methods: The International Consensus on Anaesthesia-Related Outcomes after Surgery group (ICAROS) systematic review, including randomised controlled and observational studies comparing neuraxial to general anaesthesia regarding major complications, including mortality, cardiac, pulmonary, gastrointestinal, renal, genitourinary, thromboembolic, neurological, infectious, and bleeding complications. Medline, PubMed, Embase, and Cochrane Library including Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, from 1946 to May 17, 2018 were queried. Meta-analysis and Grading of Recommendations Assessment, Development and Evaluation approach was utilised to assess evidence quality and to develop recommendations. Results: The analysis of 94 studies revealed that neuraxial anaesthesia was associated with lower odds or no difference in virtually all reported complications, except for urinary retention. Excerpt of complications for neuraxial vs general anaesthesia in hip/knee arthroplasty, respectively: mortality odds ratio (OR): 0.

Anesthesia in infancy impairs performance in recognition memory tasks in mammalian animals, but it is unknown if this occurs in humans. Successful recognition can be based on stimulus familiarity or recollection of event details. Several brain structures involved in recollection are affected by anesthesia-induced neurodegeneration in animals. Therefore, we hypothesized that anesthesia in infancy impairs recollection later in life in humans and rats. Twenty eight children ages 6-11 who had undergone a procedure requiring general anesthesia before age 1 were compared with 28 age-and gender-matched children who had not undergone anesthesia. Recollection and familiarity were assessed in an object recognition memory test using receiver operator characteristic analysis. In addition, IQ and Child Behavior Checklist scores were assessed. In parallel, thirty three 7-day-old rats were randomized to receive anesthesia or sham anesthesia. Over 10 months, recollection and familiarity were assessed using an odor recognition test. We found that anesthetized children had significantly lower recollection scores and were impaired at recollecting associative information compared with controls. Familiarity, IQ, and Child Behavior Checklist scores were not different between groups. In rats, anesthetized subjects had significantly lower recollection scores than controls while familiarity was unaffected. Rats that had undergone tissue injury during anesthesia had similar recollection indices as rats that had been anesthetized without tissue injury. These findings suggest that general anesthesia in infancy impairs recollection later in life in humans and rats. In rats, this effect is independent of underlying disease or tissue injury.

Volatile anesthetics are used widely for achieving a state of unconsciousness, yet these agents are incompletely understood in their mechanisms of action and effects on neural development. There is mounting evidence that children exposed to anesthetic agents sustain lasting effects on learning and memory. The explanation for these behavioral changes remains elusive, although acute neuronal death after anesthesia is commonly believed to be a principal cause. Rodent models have shown that isoflurane exposure in newborns induces acute neuroapoptosis and long-term cognitive impairment. However, the assessment of predisposing factors is lacking. We investigated the role of sex by delivering isoflurane to postnatal day (P)7 male and female Sprague Dawley rats for 4 hours. Brain cell death was assessed 12 h later using FluoroJade C staining in the thalamus, CA1-3 regions of hippocampus, and dentate gyrus. Behavior was assessed separately using a series of object recognition tasks and a test of social memory beginning at P38. We found that isoflurane exposure significantly increased neuronal death in each brain region with no difference between sexes. Behavioral outcome was also equivalent in simple novel object recognition. However, only males were impaired in the recognition of objects in different locations and contexts. Males also exhibited deficient social memory while females were intact. The profound behavioral impairment in males relative to females, in spite of comparable cell death, suggests that males are more susceptible to long-term cognitive effects and this outcome may not be exclusively attributed to neuronal death.

Reports of strategies to prevent and treat the opioid epidemic are growing. Significant attention has been paid to the benefits of opioid addiction research, clinical prescribing, and public policy initiatives in curbing the epidemic. However, the role of the anaesthesiologist in minimising opioid use and misuse remains underexplored. For many patients with an opioid use disorder, the perioperative period represents the source of initial exposure. As perioperative physicians, anaesthesiologists are in the unique position to manage pain effectively while simultaneously decreasing opioid consumption. Multiple opportunities exist for anaesthesiologists to minimise opioid exposure and prevent subsequent persistent opioid use. We present a global strategy for decreasing perioperative opioid use and misuse among surgical patients. A historical perspective of the opioid epidemic is presented, together with an analysis of opioid supply and demand forces. We then present specific temporal strategies for opioid use reduction in the perioperative period. We emphasise the importance of preoperative identification of patients at risk for long-term opioid use and misuse, review the evidence supporting the opioid sparing capacity of individual multimodal analgesic agents, and discuss the benefits of regional anaesthesia for minimising opioid consumption. We describe postoperative and post-discharge tools, including effective multimodal analgesia and the role of a transitional pain service. Finally, we offer general institutional strategies that can be led by anaesthesiologists, identify gaps in knowledge, and offer directions for future research.

BackgroundEvidence-based international expert consensus regarding the impact of peripheral nerve block (PNB) use in total hip/knee arthroplasty surgery.MethodsA systematic review and meta-analysis: randomized controlled and observational studies investigating the impact of PNB utilization on major complications, including mortality, cardiac, pulmonary, gastrointestinal, renal, thromboembolic, neurologic, infectious, and bleeding complications.Medline, PubMed, Embase, and Cochrane Library including Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, were queried from 1946 to August 4, 2020.The Grading of Recommendations Assessment, Development, and Evaluation approach was used to assess evidence quality and for the development of recommendations.ResultsAnalysis of 122 studies revealed that PNB use (compared with no use) was associated with lower ORs for (OR with 95% CIs) for numerous complications (total hip and knee arthroplasties (THA/TKA), respectively): cognitive dysfunction (OR 0.30, 95% CI 0.17 to 0.53/OR 0.52, 95% CI 0.34 to 0.80), respiratory failure (OR 0.36, 95% CI 0.17 to 0.74/OR 0.37, 95% CI 0.18 to 0.75), cardiac complications (OR 0.84, 95% CI 0.76 to 0.93/OR 0.83, 95% CI 0.79 to 0.86), surgical site infections (OR 0.55 95% CI 0.47 to 0.64/OR 0.86 95% CI 0.80 to 0.91), thromboembolism (OR 0.74, 95% CI 0.58 to 0.96/OR 0.90, 95% CI 0.84 to 0.96) and blood transfusion (OR 0.84, 95% CI 0.83 to 0.86/OR 0.91, 95% CI 0.90 to 0.92).ConclusionsBased on the current body of evidence, the consensus group recommends PNB use in THA/TKA for improved outcomes.Recommendation: PNB use is recommended for patients undergoing THA and TKA except when contraindications preclude their use. Furthermore, the alignment of provider skills and practice location resources needs to be ensured. Evidence level: moderate; recommendation: strong.

BackgroundAnesthetic exposure early in life affects neural development and long-term cognitive function, but our understanding of the types of memory that are altered is incomplete. Specific cognitive tests in rodents that isolate different memory processes provide a useful approach for gaining insight into this issue.MethodsPostnatal day 7 (P7) rats were exposed to either desflurane or isoflurane at 1 Minimum Alveolar Concentration for 4 h. Acute neuronal death was assessed 12 h later in the thalamus, CA1-3 regions of hippocampus, and dentate gyrus. In separate behavioral experiments, beginning at P48, subjects were evaluated in a series of object recognition tests relying on associative learning, as well as social recognition.ResultsExposure to either anesthetic led to a significant increase in neuroapoptosis in each brain region. The extent of neuronal death did not differ between groups. Subjects were unaffected in simple tasks of novel object and object-location recognition. However, anesthetized animals from both groups were impaired in allocentric object-location memory and a more complex task requiring subjects to associate an object with its location and contextual setting. Isoflurane exposure led to additional impairment in object-context association and social memory.ConclusionIsoflurane and desflurane exposure during development result in deficits in tasks relying on associative learning and recognition memory. Isoflurane may potentially cause worse impairment than desflurane.

Background With growing evidence that anesthesia exposure in infancy affects cognitive development, it is important to understand how distinct anesthetic agents and combinations can alter long-term memory. Investigations of neuronal death suggest that combining anesthetic agents increases the extent of neuronal injury. However, it is unclear how the use of simultaneously combined anesthetics affects cognitive outcome relative to the use of a single agent. Methods Postnatal day (P)7 male rats were administered either sevoflurane as a single agent or the combined delivery of sevoflurane with nitrous oxide at 1 Minimum Alveolar Concentration for 4 h. Behavior was assessed in adulthood using the forced alternating T-maze, social recognition, and context-specific object recognition tasks. Results Animals exposed to either anesthetic were unimpaired in the forced alternating T-maze test and had intact social recognition. Subjects treated with the combined anesthetic displayed a deficit, however, in the object recognition task, while those treated with sevoflurane alone were unaffected. Conclusion A combined sevoflurane and nitrous oxide anesthetic led to a distinct behavioral outcome compared with sevoflurane alone, suggesting that the simultaneous use of multiple agents may uniquely influence early neural and cognitive development and potentially impacts associative memory.

Background Patients often have moderate to severe pain after rotator cuff surgery, despite receiving analgesics and nerve blocks. There are many suggested ways to improve pain after rotator cuff surgery, but the effects of adopting a pathway that includes formal patient education, a long-acting nerve block, and extensive multimodal analgesia are unclear. Questions/purposes (1) Does adoption of a clinical pathway incorporating patient education, a long-acting nerve block, and preemptive multimodal analgesia reduce the worst pain during the first 48 hours after surgery compared with current standard institutional practices? (2) Does adoption of the pathway reduce opioid use? (3) Does adoption of the pathway reduce side effects and improve patient-oriented outcomes? Methods From September 2018 to January 2020, 281 patients scheduled for arthroscopic ambulatory rotator cuff surgery were identified for this paired sequential prospective cohort study. Among patients in the control group, 177 were identified, 33% (58) were not eligible, for 11% (20) staff was not available, 56% (99) were approached, 16% (29) declined, 40% (70) enrolled, and 40% (70) were analyzed (2% [4] lost to follow-up for secondary outcomes after postoperative day 2). For patients in the pathway cohort, 104 were identified, 17% (18) were not eligible, for 11% (11) staff was not available, 72% (75) were approached, 5% (5) declined, 67% (70) enrolled, and 67% (70) were analyzed (3% [3] lost to follow-up for secondary outcomes after postoperative day 2). No patients were lost to follow-up for primary outcome; for secondary outcomes, four were lost in the control group and three in the pathway group after postoperative day 2 (p = 0.70). The initial 70 patients enrolled received routine care (control group), and in a subsequent cohort, 70 patients received care guided by a pathway (pathway group). Of the 205 eligible patients, 68% (140) were included in the analysis. This was not a study comparing two tightly defined protocols but rather a study to determine whether adoption of a pathway would alter patient outcomes. For this reason, we used a pragmatic (real-world) study design that did not specify how control patients would be treated, and it did not require that all pathway patients receive all components of the pathway. We developed the pathway in coordination with a group of surgeons and anesthesiologists who agreed to apply the pathway as much as was viewed practical for each individual patient. Patients in both groups received a brachial plexus nerve block with sedation. Major differences between the pathway and control groups were: detailed patient education regarding reasonable pain expectations with a goal of reducing opioid use (no formal educational presentation was given to the control), a long-acting nerve block using bupivacaine with dexamethasone (control patients often received shorter-acting local anesthetic without perineural dexamethasone), and preemptive multimodal analgesia including intraoperative ketamine, postoperative acetaminophen, NSAIDs, and gabapentin at bedtime, with opioids as needed (control patients received postoperative opioids but most did not get postoperative NSAIDS and no controls received gabapentin or separate prescriptions for acetaminophen). The primary outcome was the numerical rating scale (NRS) worst pain with movement 0 to 48 hours after block placement. The NRS pain score ranges from 0 (no pain) to 10 (worst pain possible). The minimum clinically important difference (MCID) [12] for NRS that was used for calculation of the study sample size was 1.3 [18], although some authors suggest 1 [13] or 2 [5] are appropriate; if we had used an MCID of 2, the sample size would have been smaller. Secondary outcomes included NRS pain scores at rest, daily opioid use (postoperative day 1, 2, 7, 14), block duration, patient-oriented pain questions (postoperative day 1, 2, 7, 14), and patient and physician adherence to pathway. Results On postoperative day 1, pathway patients had lower worst pain with movement (3.3 ± 3.1) compared with control patients (5.6 ± 3.0, mean difference -2.7 [95% CI -3.7 to -1.7]; p < 0.001); lower scores were also seen for pain at rest (1.9 ± 2.3 versus 4.0 ± 2.9, mean difference -2.0 [95% CI -2.8 to -1.3]; p < 0.001). Cumulative postoperative opioid use (0-48 hours) was reduced (pathway oral morphine equivalent use was 23 ± 28 mg versus 44 ± 35 mg, mean difference 21 [95% CI 10 to 32]; p < 0.01). The greatest difference in opioid use was in the first 24 hours after surgery (pathway 7 ± 12 mg versus control 21 ± 21 mg, mean difference -14 [95% CI -19 to -10]; p < 0.01). On postoperative day 1, pathway patients had less interference with staying asleep compared with control patients (0.5 ± 1.6 versus 2.6 ± 3.3, mean difference -2.2 [95% CI -3.3 to -1.1]; p < 0.001); lower scores were also seen for interference with activities (0.9 ± 2.3 versus 1.9 ± 2.9, mean difference -1.1 [95% CI -2 to -0.1]; p = 0.03). Satisfaction with pain treatment on postoperative day 1 was higher among pathway patients compared with control patients (9.2 ± 1.7 versus 8.2 ± 2.5, mean difference 1.0 [95% CI 0.3 to 1.8]; p < 0.001). On postoperative day 2, pathway patients had lower nausea scores compared with control patients (0.3 ± 1.1 versus 1 ± 2.1, mean difference -0.7 [95% CI -1.2 to -0.1]; p = 0.02); lower scores were also seen for drowsiness on postoperative day 1 (1.7 ± 2.7 versus 2.6 ± 2.6, mean difference -0.9 [95% CI - 1.7 to -0.1]; p = 0.03). Conclusion Adoption of the pathway was associated with improvement in the primary outcome (pain with movement) that exceeded the MCID. Patients in the pathway group had improved patient-oriented outcomes and fewer side effects. This pathway uses multiple analgesic drugs, which may pose risks to elderly patients, in particular. Therefore, in evaluating whether to use this pathway, clinicians should weigh the effect sizes against the potential risks that may emerge with large scale use, consider the difficulties involved in adapting a pathway to local practice so that pathway will persist, and recognize that this study only enrolled patients among surgeons and the anesthesiologists that advocated for the pathway; results may have been different with less enthusiastic clinicians. This pathway, based on a long-lasting nerve block, multimodal analgesia, and patient education can be considered for adoption. Level of Evidence Level II, therapeutic study.