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

Purpose: The ideal sedative should have a rapid onset, short duration, and quick and predictable recovery. Despite the increasing use of the recently developed sedative remimazolam for intraoperative sedation, there is a paucity of research on its comparative recovery profile. Our aim was to compare the recovery profiles of intraoperative sedation with propofol, dexmedetomidine, and remimazolam in patients undergoing surgery under regional anesthesia.

Methods: We included 119 patients scheduled to undergo upper limb surgery under brachial plexus blockade in a randomized controlled trial. We randomized patients to receiving intraoperative sedation with propofol, dexmedetomidine, or remimazolam. The primary outcome was the recovery time (from the completion of infusion to attaining a Modified Observer's Assessment of Alertness and Sedation score of 5). As secondary outcomes, we assessed other recovery profiles, including length of stay, quality of recovery, and the Aldrete score.

Results: The mean (95% confidence interval [CI]) recovery time was 19 min (95% CI, 16 to 22) for patients in the dexmedetomidine group, 17 min (95% CI, 15 to 19) for the remimazolam group, and 12 min (95% CI, 10 to 13) for the propofol group (P < 0.001). Post hoc analysis revealed that the recovery time in the remimazolam group was longer compared to that in the propofol group (mean difference, 5 min; 95% CI, 3 to 8; Bonferroni adjusted P < 0.001). We found no significant differences among the three groups in the recovery-related secondary outcomes (all P > 0.05).

Conclusions: Patients in the propofol group exhibited the most rapid recovery time from intraoperative sedation under regional anesthesia, followed by those in the remimazolam and dexmedetomidine groups. We found no differences in the recovery-related secondary outcomes.

Study registration: ClinicalTrials.gov ( NCT05688345 ); first submitted 30 December 2022.

Purpose: We aimed to evaluate the effects of intravenous dexmedetomidine (DEX) on perioperative opioid requirements, and secondarily on perioperative respiratory adverse events (PRAE), emergence delirium (ED), and postoperative nausea and vomiting in pediatric patients undergoing tonsillectomy.

Methods: We conducted a systematic review with meta-analysis, searching seven databases up to 7 May 2024. We included randomized controlled trials of patients aged 18 yr or younger undergoing tonsillectomy, comparing intravenous DEX and opioids with opioids. Our primary outcome was perioperative opioid requirements, expressed as oral morphine equivalents (OME). The secondary outcomes included the incidences of perioperative respiratory adverse events (PRAE), emergence delirium (ED), and postoperative nausea and vomiting (PONV), We used the Cochrane Risk of Bias 2 tool and assessed the certainty of the evidence with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE). We used a pairwise random effects model to compute the risk ratios (RRs) or mean differences (MDs) with 95% confidence intervals (CIs) of the effects of DEX on each outcome. To explore dose-dependent effects of DEX, we used a random effects meta-regression model.

Results: We included 16 trials in our systematic review, of which we analyzed 7 for opioid requirements, 4 for PRAE, 3 for ED, and 12 for PONV. Dexmedetomidine was associated with lower perioperative opioid requirements (MD, -0.25 mg·kg^-1 OME; 95% CI, -0.36 to -0.13; moderate certainty), equivalent to a 40% relative reduction of perioperative OME, and a lower likelihood of ED (RR, 0.24; 95% CI, 0.08 to 0.71; moderate certainty). Despite DEX not having a dose-dependent effect on OME, the RR of ED decreased 87% for each 0.5 µg·kg^-1 increment in DEX dose. Dexmedetomidine did not reduce the incidence of sustained or severe cough as a part of PRAE, but it reduced PONV (RR, 0.48; 95% CI, 0.35 to 0.66; I² = 0%; low certainty).

Conclusion: Dexmedetomidine may improve the perioperative course of children undergoing tonsillectomy by decreasing perioperative opioid requirements and dose-dependently lowering the incidence of ED. Limitations of the present systematic review with meta-analysis include an inconsistent definition of PRAE in trials and heterogeneity due to variability of observed effect sizes.

Study registration: PROSPERO ( CRD42023392579 ); first submitted 1 July 2023.

Purpose: Cardiac arrest can cause hypoxic-ischemic injury and result in both spinal cord injury and death determination by neurologic criteria (DNC). The presence and severity of hypoxic-ischemic spinal cord injury (HISCI) impacts neuro-prognostication, rehabilitation, and may confound DNC evaluation in patients by interfering with motor responses and respiratory muscle function in apnea testing. We describe five children with postarrest HISCI detected on magnetic resonance imaging (MRI) and supplement our observations with a literature review.

Clinical features: Postarrest HISCI was identified in five consecutive pediatric cases of prolonged cardiac arrest and hypoxic-ischemic brain injury in a single centre. All patients had cardiopulmonary resuscitation for > 30 min and resultant severe hypoxic-ischemic brain injury. Spinal MRI indications were loss of rectal tone (n = 3), focal deficit (n = 1), and practice change related to recent cases (n = 1). A rapid review of the literature yielded case reports, case series, and retrospective reviews describing 90 patients (81 adults; nine pediatric) with postarrest HISCI. Ischemia distribution was variable, most frequently reported at the cervical and thoracic levels, although some patients had ischemia of the entire cord. Paraplegia was the most common deficit among survivors. There were no reports of HISCI in patients who underwent assessment for DNC.

Conclusions: This case series and rapid literature review highlights that both adults and children may be at risk of HISCI after prolonged cardiac arrest. Our findings suggest that further research should focus on determining the incidence and sequelae of HISCI after resuscitated cardiac arrest, as well as evaluating its potential impact on DNC practice and neuro-prognostication.

Purpose: Spinal cord stimulation (SCS) is a surgical intervention for patients with neuropathic pain refractory to medical management. There are limited data on its outcomes from Canadian centres. We aimed to describe the indications, patient- and procedure-related characteristics, and outcomes of patients who underwent SCS implantation at a Canadian tertiary centre.

Methods: We conducted a retrospective cohort study of patients who underwent SCS at St. Michael's Hospital (Toronto, ON, Canada) between 1 January 2020 and 31 July 2023. We collected data on patient demographics, analgesic use, type of SCS trial (percutaneous vs tunneled), indication, antibiotic use during and after surgery, and complications.

Results: We included 100 patients with a mean (standard deviation) age of 62 (14) yr. Indications included chronic pain after spinal surgery (n = 44), chronic back pain (no prior spine surgery) (n = 22), complex regional pain syndrome (n = 6), spinal stenosis (n = 4), and visceral pain (n = 4). Complications included implantable pulse generator-associated pain (47%), lead migration (14%), lead fracture (9%), surgical site infection (2%), and cerebrospinal fluid leak (6%). Almost all patients were on pharmacotherapy for pain relief at baseline (n = 96) and agents included opioids, nonsteroidal anti-inflammatory drugs, anticonvulsants, and antidepressants.

Conclusions: In this cohort of patients who underwent SCS implantation at a Canadian tertiary centre, infection and lead migration rates were consistent with global estimates (3.8% and up to 27%, respectively); nevertheless, we observed high rates of dural puncture compared with an expected incidence of 0.48%.

Purpose: Brainwave entrainment with low-frequency binaural beats has shown sedative-sparing and anxiolytic effects. We sought to investigate whether the preoperative use of binaural beats could reduce the propofol dose for the induction of general anesthesia.

Methods: We enrolled patients scheduled for elective surgery under general anesthesia in a randomized controlled trial. In the preoperative waiting area, we randomized patients to hear the binaural beats with frequencies of 432 and 431 Hz in the binaural-beats group (N = 34) or silent sound in the control group (N = 35) for 20 min via stereo headphones. For the induction of general anesthesia, we administered 10 mg of propofol every 15 sec until we observed three clinical signs: the loss of response to verbal commands of "open your eyes" (primary outcome), loss of eyelash reflex, and a patient state index of ≤ 50. We collected processed frontal electroencephalography data during the intervention and assessed anxiety scores before and after the intervention.

Results: The propofol dose for the loss of response to verbal commands was lower in the binaural-beats group than in the control group (mean [standard deviation], 87 [24] mg vs 105 [32] mg; difference in means, -18 mg; 95% confidence interval, -32 to -5; P = 0.009). There were no significant differences in the delta (P = 0.63), theta (P = 0.28), alpha (P = 0.24), and beta (P = 0.85) bands of the processed frontal electroencephalograms and the anxiety scores (P = 0.50).

Conclusion: Binaural beats with a frequency of 1 Hz modestly reduced the propofol dose for the induction of general anesthesia, but we observed no significant differences in the processed frontal electroencephalograms and preoperative anxiety levels.

Study registration: ClinicalTrials.gov ( NCT05431881 ); first submitted 9 June 2022.

Purpose: We sought to conduct a systematic review to determine the diagnostic test accuracy of point-of-care ultrasound (POCUS) for the specific etiologies and subtypes of shock.

Methods: We searched MEDLINE, Embase, and the grey literature for prospective studies in adult populations with shock. We collected data on study design, patient characteristics, operator characteristics, POCUS protocol, and true and false positives and negatives, and assessed the risk of bias.

Results: We found 18 eligible studies with a total of N = 2,088 patients. The pooled sensitivity and specificity of POCUS for determining shock subtype were 90% (95% confidence interval [CI], 81 to 95) and 95% (95% CI, 90 to 97) for hypovolemic shock, 95% (95% CI, 84 to 98) and 98% (95% CI, 97 to 99) for cardiogenic shock, 78% (95% CI, 69 to 85) and 97% (95% CI, 94 to 99) for distributive shock, 94% (95% CI, 85 to 97) and 99% (95% CI, 98 to 100) for obstructive shock, and 85% (95% CI, 77 to 91) and 98% (95% CI, 91 to 100) for mixed shock (all low to moderate quality evidence). The pooled sensitivity and specificity of POCUS for determining specific shock etiologies were 78% (95% CI, 18 to 98) and 96% (95% CI, 87 to 99) for sepsis, 92% (95% CI, 71 to 98) and 99% (95% CI, 83 to 100) for pulmonary embolism, and 100% (95% CI, 69 to 100) and 100% (95% CI, 98 to 100) for cardiac tamponade. The quality of the evidence ranged from very low to moderate.

Conclusions: On the basis of very low to moderate quality evidence, POCUS may perform better at ruling in shock subtypes and specific shock etiologies than ruling them out. Point-of-care ultrasound is a promising tool for the diagnosis of shock.

Study registration: PROSPERO ( CRD42020160001 ); first submitted 1 December 2019.

Purpose: ChatGPT and other large language models (LLMs) have gained immense popularity since their commercial release in 2022, with applications in various sectors including health care. We sought to evaluate their deployment in anesthesiology and critical care in a systematic review. Our aim was to describe the integration of LLMs in the field by showcasing and categorizing their current applications, assessing their performance in patient care, and reviewing application-specific ethical and practical challenges in deployment.

Methods: Respecting Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, we systematically searched through PubMed®, Embase, the Cochrane Central Register of Controlled Trials, and Web of Science®, from inception until 1 August 2024. We extracted all papers investigating LLMs in anesthesiology or critical care and reporting results. We segmented the literature into major themes and highlighted key findings and limitations.

Results: From 480 retrieved articles, we included 45 papers. The evaluated models (GPT-4, GPT-3.5, Google Bard [now Gemini], LLaMA, and others) showed diverse applications in four segments: intensive care unit, patient education, medical education, and perioperative care. Large language models, especially newer models, are promising in predicting clinical scores, navigating simple clinical scenarios, and managing preoperative anxiety. Their performance remains below the clinician level in predicting outcomes, solving complex clinical scenarios (i.e., airway management), board examinations, and generating patient-directed documents, although newer models performed better than older ones.

Conclusion: While LLMs are not yet equipped to fully assist physicians in anesthesiology and critical care, they have significant potential, and their capabilities are rapidly improving. Supervised use for select tasks can streamline patient care. Further trials are warranted as new versions of models become available.

Study registration: PROSPERO ( CRD42024567380 ); first submitted 22 July 2024.