Korean Journal of Anesthesiology最新文献

Background: Flexor hallucis longus tenosynovitis (FHLTS) is the inflammation of the sheath through which the flexor hallucis longus tendon (FHLT) passes. The FHLT thickness (FHLTT) is correlated with ankle pain. Thus, the FHLTT is considered a characteristic FHLTS feature. However, asymmetrical thickening of the FHLT can occur at any point. Therefore, we used the FHLT cross-sectional area (FHLTCSA) as a new morphological parameter to diagnose FHLTS.

Methods: 26 participants in the Control group (Group 1) and 26 in the FHLTS group (Group 2) underwent magnetic resonance imaging. The FHLTCSA was calculated for the ligament based on the images showing the maximum hypertrophic changes. The FHLTT was measured based on the images showing the FHLT with the maximum thickness.

Results: The mean FHLTCSA was 7.86 ± 1.88 mm2 and 13.11 ± 2.31 mm2 in Groups 1 and 2, respectively. The average FHLTT was 2.35 ± 0.55 mm and 2.91 ± 0.37 mm in Groups 1 and 2, respectively. The FHLTCSA (P < 0.001) and FHLTT (P < 0.001) in Group 2 were significantly greater than those in Group 1. Receiver operating characteristic curve analysis revealed that the optimal cutoff value for the FHLTCSA was 10.37 mm2, with a sensitivity of 92.3%, a specificity of 92.3%, and an area under the curve (AUC) of 0.97. The optimal cutoff value for the FHLTT was 2.71 mm, with a sensitivity of 76.9%, a specificity of 76.9%, and an AUC of 0.84.

Conclusions: The FHLTCSA is a sensitive morphological parameter for assessing FHLTS.

Background: Elderly patients commonly experience sudden hypotension after propofol administration for anesthesia induction. Remimazolam, a novel anesthetic agent, offers superior hemodynamic stability, and thus represents a potentially safer alternative to propofol in this vulnerable population. However, the optimal infusion rate of remimazolam for inducing general anesthesia in elderly patients remains unclear. This study aimed to determine the effective infusion rate of remimazolam for general anesthesia induction in elderly patients.

Methods: This study enrolled consecutive patients aged ≥ 65 with an American Society of Anesthesiologists (ASA) physical status I-III who underwent elective surgery. The 50% (50% effective dose [ED50]) and 90% (90% effective dose [ED90]) effective infusion rates of remimazolam for inducing general anesthesia were estimated using the k-in-a-row method. Successful anesthesia induction was defined as achieving a Modified Observer's Assessment of Alertness/Sedation (MOAA/S) score of ≤ 1 within 2 min of initiating remimazolam infusion. The initial infusion rate was set at 0.1 mg/kg/min, with subsequent adjustments made in increments/decrements of 0.02 mg/kg/min. According to the k-in-a-row method, the infusion rate increased after failure, but decreased only after k = 6 consecutive successes.

Results: A total of 50 patients were enrolled in this study. The estimated ED50 and ED90 for achieving an MOAA/S score ≤ 1 within 2 min from the start of remimazolam infusion were 0.10 mg/kg/min (90% CI [0.08-0.11]) and 0.13 mg/kg/min (0.12-0.19), respectively. Hemodynamic stability was maintained across all tested doses during the induction period, and none of the patients required vasopressors or inotropes.

Conclusions: An infusion rate of 0.13 mg/kg/min of remimazolam effectively induces general anesthesia in elderly patients, while preserving hemodynamic stability.

Background: Postoperative delirium (POD) is a common and serious complication in older adults. Prior studies have validated serum amyloid A (SAA) as a potential biomarker for various inflammatory conditions; however, its role in POD is poorly characterized. This study aimed to examine the association between preoperative SAA levels and the occurrence of POD.

Methods: This study comprised a retrospective review of the electronic medical records of patients aged 60 and older who underwent hip surgery between April 2022 and January 2024. Cognitive function was assessed using the Nursing Delirium Screening Scale (Nu-DESC), while diagnosis was confirmed by psychiatrists using the Confusion Assessment Method (CAM). The associations between POD occurrence and preoperative/postoperative SAA levels and other patient, anesthesia, and surgical factors were analyzed using logistic regression models.

Results: Of 731 patients, delirium occurred in 121 patients (16.6%) within the first five postoperative days (five-day POD). Preoperative SAA levels were significantly higher in the POD group (91.2 mg/L) than the non-POD group (6.6 mg/L) (P < 0.001). Logistic regression showed that preoperative SAA levels were independently associated with POD occurrence (odds ratio [OR]: 1.005, 95% CI: 1.002‒1.008; P < 0.001). Age (P < 0.001), height (P = 0.006), and preoperative albumin levels (P = 0.008) were also identified as significant factors influencing POD risk.

Conclusions: Elevated preoperative SAA levels were associated with an increased risk of five-day POD in older adults undergoing hip surgery. Further research is required to explore the clinical utility of SAA as a biomarker for predicting POD.

Background: Despite the well-known effects of elevated bilirubin in neonates, its neurotoxic potential in adults remains uncertain. In perioperative and hepatic disease contexts, transient bilirubin elevations are common; however, their direct contribution to cognitive dysfunction has not been clearly established. This study aimed to determine whether transient bilirubin elevation alone can impair cognition and disrupt blood-brain barrier (BBB) function in adult zebrafish, and to compare these effects with those of liver injury.

Methods: Adult zebrafish were assigned to either a bilirubin-injected group (retro-orbital injection of bilirubin) or a liver injury group (hepatocyte-specific ablation using a nitroreductase/metronidazole system). Cognitive performance was assessed using the T-maze test, and BBB integrity was evaluated using Evans blue staining. Expression of inflammatory genes (il1b, stat1b, ifng1) in brain tissue was analyzed via reverse transcription quantitative polymerase chain reaction.

Results: Zebrafish injected with bilirubin exhibited impaired spatial learning without locomotor deficits, accompanied by marked Evans blue accumulation, indicating BBB disruption. Zebrafish in the liver injury group exhibited similar cognitive impairment and a modest increase in BBB permeability, yet displayed significantly higher expression of inflammatory genes. These findings suggest that, although both models induce behavioral deficits, their underlying mechanisms may differ.

Conclusion: Transient bilirubin elevation alone was sufficient to impair cognition and disrupt BBB function in adult zebrafish, even in the absence of overt liver damage or systemic inflammation. Although inflammation is more pronounced during liver injury, bilirubin itself may exert direct neurovascular effects. These results support considering bilirubin levels as a modifiable risk factor for perioperative neurocognitive dysfunction.

Background: High-dose insulin and euglycemic therapy are widely used to treat calcium channel blocker toxicity. However, the effect of insulin on vasodilation evoked by the dihydropyridine calcium channel blocker amlodipine remains unknown. This study examined the effect of insulin on amlodipine-induced vasodilation in isolated rat aortas with specific emphasis on mechanisms associated with nitric oxide (NO).

Methods: The study assessed the roles of NW-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor; methylene blue, a general guanylate cyclase suppressor; 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), a selective inhibitor of NO-sensitive guanylate cyclase; and endothelial removal in modulating the NO-dependent signaling cascade underlying amlodipine-induced vasodilation. This study explored how insulin and various pharmacological inhibitors influenced the vasodilatory effects of amlodipine and verapamil in rat aortic tissues with or without an intact endothelium.

Results: In aortas with intact endothelium, amlodipine-induced relaxation was significantly suppressed by L-NAME, methylene blue, and ODQ. Insulin enhanced amlodipine-induced vasodilation in endothelium-intact aortas, whereas it had no effect on the vasodilatory response to amlodipine in endothelium-denuded aortas. Moreover, L-NAME, methylene blue, and ODQ eliminated insulin-mediated augmentation of amlodipine-induced vasodilation in endothelium-intact aortas. However, in endothelium-intact aortas, insulin exhibited no impact on the vasodilatory effects triggered by verapamil. Amlodipine increased endothelial nitric oxide synthase (eNOS) phosphorylation in human umbilical vein endothelial cells (HUVECs). Additionally, combined treatment with insulin and amlodipine further increased amlodipine-induced eNOS phosphorylation in HUVECs.

Conclusions: These findings suggest that insulin contributes to the amplification of amlodipine's NO-dependent vasodilatory response in aortas, which appears to be mediated by increased NO production.

Background: Delirium is a common complication among critically ill patients. This study analyzed trends in dexmedetomidine use and its association with delirium incidence, severity, and outcomes in a surgical intensive care unit (ICU).

Methods: A retrospective cohort study was performed in the surgical ICU of a tertiary academic center in South Korea, including 6,140 adult patients admitted from 2017 to 2023. Patients were grouped by dexmedetomidine exposure. Delirium was assessed using the Intensive Care Delirium Screening Checklist (ICDSC). Outcomes included delirium incidence, ICU length of stay (LOS), and one-year postoperative survival. Multivariate logistic regression identified delirium risk factors; Kaplan-Meier analysis assessed survival.

Results: Dexmedetomidine use increased over time. Patients receiving dexmedetomidine had higher delirium incidence (46.1% vs. 13.9%, P < 0.001) and longer ICU stays (5.7 vs. 2.1 d, P < 0.001). They received 0.37 ± 0.16 µg/kg/h for 9.4 ± 6.5 h/d over 2.3 ± 4.0 d on average. Independent delirium risk factors were dexmedetomidine use (odds ratio [OR] 3.14; 95% CI 2.43-4.06), older age, psychiatric medication, and higher American Society of Anesthesiologists (ASA) physical status classification and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores. One-year postoperative survival was lower in the dexmedetomidine group (92.7% vs. 94.5%, P = 0.015), likely due to greater illness severity.

Conclusions: Dexmedetomidine was mainly used in high-risk, severely ill patients, reflecting its role in managing severe symptoms rather than preventing delirium. These results highlight the need for personalized sedation strategies to optimize dexmedetomidine use in the ICU setting.

Background: With the growing adoption of minimally invasive surgery, single-port total laparoscopic hysterectomy (TLH) is gaining popularity. However, unlike multi-port TLH, evidence on optimal pain management strategies for single-port TLH remains limited. Given the key role of regional anesthesia in multimodal analgesia, identifying the more effective block technique is clinically relevant. This study aimed to compare the analgesic efficacy of the quadratus lumborum block (QLB) and rectus sheath block (RSB) in patients undergoing single-port TLH. We hypothesized that QLB would result in lower 24-hour cumulative opioid consumption than RSB.

Methods: In this prospective, randomized trial, 62 patients undergoing single-port TLH were assigned to receive either RSB or QLB. The primary outcome was 24-hour cumulative opioid consumption. Secondary outcomes included time to first patient-controlled analgesia (PCA) bolus, pain scores, and the need for rescue analgesia.

Results: Data from 52 patients were analyzed (RSB: 27; QLB: 25). Median 24-hour opioid consumption was significantly lower in the RSB group (277.9 versus 459.1 μg; P = 0.007). Although the median time to first PCA bolus was similar between groups, Kaplan-Meier survival analysis revealed a marginal but statistically significant difference favoring RSB (P = 0.047). Notably, no patients in the RSB group required rescue analgesia, compared to 20% in the QLB group (P = 0.020).

Conclusions: RSB provided superior postoperative analgesia compared to QLB in single-port TLH, reducing both opioid consumption and the need for rescue analgesia. These findings support RSB as the preferred block within a multimodal analgesia strategy for this procedure.

Background: The hypotension prediction index (HPI) is an algorithm designed to predict hypotension. Some studies have reported that HPI-guided hemodynamic management strategies decrease intraoperative hypotension and complications; however, the effect of HPI on reducing perioperative complications are controversial. This meta-analysis aimed to assess the efficacy of the HPI in reducing major complications and intraoperative hypotension.

Methods: We conducted this meta-analysis according to the PRISMA statement and Cochrane Handbook guidelines. A comprehensive literature review was conducted to identify studies focusing on the efficacy of HPI-guided management in reducing intraoperative hypotension and postoperative complications. The PubMed, Embase, Scopus, and Web of Science databases were searched, and the resulting data were combined to calculate the pooled mean differences (MDs) or risk ratios (RRs) with 95% CIs of both randomized controlled trials (RCTs) and retrospective studies, as appropriate. Heterogeneity and potential publication bias were also assessed.

Results: Nineteen articles (12 RCTs and 7 retrospective studies) with 2,570 recruited patients were included in this meta-analysis. The critical evaluation of the study quality revealed a low risk of bias in the included RCTs. Among the non-randomized trials, one was rated 7, two were rated 8, and the remaining four were rated 9 on the Newcastle-Ottawa Scale, indicating high quality and a low risk of bias. HPI-guided management significantly reduced intraoperative hypotension and associated major complications (RR = 0.79, 95% CI [0.69, 0.90], I2 = 0; P = 0.0005). Blood loss and length of hospital stay were comparable between the groups.

Conclusions: HPI-guided management significantly reduced intraoperative hypotension and major complications.