Comparison of the Effect of Landmark-Based Midline and Paramedian Approaches on Spinal Anesthesia-Related Complications in Adult Patients: A Meta-Analysis of Randomized Controlled Trials.

Background and Objectives: Spinal anesthesia is widely used in various types of surgery. However, several complications can occur afterward. This study aimed to identify differences in the incidence of anesthesia-related complications according to the approach methods (midline versus paramedian) for landmark-based spinal anesthesia. Materials and Methods: We searched electronic databases, including PubMed, EMBASE, CENTRAL, Scopus, and Web of Science, for eligible randomized controlled trials. The primary outcome was post-dural puncture headache (PDPH) incidence, and secondary outcomes were low back pain (LBP) incidence and success rate in the first trial of spinal anesthesia. We estimated the odds ratio (OR) with 95% confidence intervals (CI) using a random-effects model. Results: In total, 2280 patients from 13 randomized controlled trials were included in the final analysis. The incidence rates of PDPH were 5.9% and 10.4% in the paramedian and midline approach groups, respectively. The pooled effect size revealed that the incidence of PDPH (OR: 0.43, 95% CI [0.22-0.83]; p = 0.01; I2 = 53%) and LBP (OR: 0.27, 95% CI [0.16-0.44]; p < 0.001; I2 = 16%) decreased, and the success rate in the first attempt was higher (OR: 2.30, 95% CI [1.36-3.87]; p = 0.002; I2 = 35%) with the paramedian than with the midline approach. Conclusions: Paramedian spinal anesthesia reduced PDPH and LBP and increased the success rate of the first attempt.

Postoperative Delirium after Dexmedetomidine versus Propofol Sedation in Healthy Older Adults Undergoing Orthopedic Lower Limb Surgery with Spinal Anesthesia: A Randomized Controlled Trial.

BACKGROUND: Delirium is a critical postoperative complication in older patients. Based on the hypothesis that intraoperative dexmedetomidine sedation would lower postoperative delirium than propofol sedation would, the authors compared the incidence of postoperative delirium in older adults, using the mentioned sedatives. METHODS: This double-blinded, randomized controlled study included 748 patients, aged 65 yr or older, who were scheduled for elective lower extremity orthopedic surgery, between June 2017 and October 2021. Patients were randomized equally into two groups in a 1:1 ratio according to the intraoperative sedative used (dexmedetomidine vs. propofol). The postoperative delirium incidence was considered the primary outcome measure; it was determined using the confusion assessment method, on the first three postoperative days. The mean arterial pressure and heart rate were evaluated as secondary outcomes. RESULTS: The authors enrolled 732 patients in the intention-to-treat analyses. The delirium incidence was lower in the dexmedetomidine group than in the propofol group (11 [3.0%] vs. 24 [6.6%]; odds ratio, 0.42; 95% CI, 0.201 to 0.86; P = 0.036). During sedation, the mean arterial pressure (median [interquartile range] mmHg) was higher in the dexmedetomidine group (77 [71 to 84]) than in the propofol group (74 [69 to 79]; P < 0.001); however, it significantly fell lower (74 [68 to 80]) than that of the propofol group (80 [74 to 87]) in the postanesthesia care unit (P < 0.001). Lower heart rates (beats/min) were recorded with the use of dexmedetomidine than with propofol, both during sedation (60 [55 to 66] vs. 63 [58 to 70]) and in the postanesthesia care unit (64 [58 to 72] vs. 68 [62-77]; P < 0.001). CONCLUSIONS: Dexmedetomidine showed a lower incidence of postoperative delirium than propofol in healthy older adults undergoing lower extremity orthopedic surgery.

The Involvement of the Hypothalamus-Pituitary-Adrenal Axis in the Development of Hyperalgesia during the Early Postoperative Period.

INTRODUCTION: Hyperalgesia frequently occurs after surgery and is associated with adverse effects on surgical outcomes. Thus, we aimed to examine whether the hypothalamus-pituitary-adrenal (HPA) axis function after surgery is involved in the development of postoperative hyperalgesia. METHODS: Surgery- and pain-related variables were measured 24 and 48 h after the first and second total knee arthroplasties (TKAs) in postmenopausal patients undergoing 1-week-interval staged bilateral TKA. Two sets of saliva samples were consecutively collected from patients before (pre-T1) and 1 week after (post-T1) the first TKA (n = 69). HPA axis function was analyzed in a subgroup of 20 patients with a typical cortisol awakening response (CAR) in both the sets of saliva samples. RESULTS: Surgery-related variables were comparable between the first and second TKAs. However, pain-related variables (pain ratings and the amount of opioid analgesics consumed) were greater after the second than the first TKA. Cortisol and dehydroepiandrosterone (DHEA) secretion during the post-awakening period (CARauc and Daucawk, respectively) was higher at post-T1 than at pre-T1, but the molar CARauc/Daucawk ratio was comparable between the time points examined. No relationship was observed between the pre-T1 CARauc and pain ratings after the first TKA. However, post-T1 CARauc showed a positive correlation with pain ratings after the second TKA. Postoperative pain ratings were negatively correlated with Daucawk and positively correlated with the molar CARauc/Daucawk ratio at all examined time points. DISCUSSION/CONCLUSION: The results suggest that adrenocortical steroidogenic activity favoring the production of cortisol over DHEA after surgery may contribute to the development of hyperalgesia during the early postoperative period.

Effect of the Paravertebral Block on Chronic Postsurgical Pain After Thoracic Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

OBJECTIVE: This study aimed to identify the benefits of thoracic paravertebral block (PVB) by focusing on its role in reducing chronic postsurgical pain (CPSP) after thoracic surgery. DESIGN: A systematic review and meta-analysis of randomized controlled trials (RCTs). SETTING: Electronic databases, including PubMed, EMBASE, CENTRAL, Scopus, and Web of Science, were searched to identify studies. PARTICIPANTS: Patients undergoing thoracic surgeries. INTERVENTION: Paravertebral block for postoperative analgesia. MEASUREMENT AND MAIN RESULTS: A total of 1,028 adult patients from 10 RCTs were included in the final analysis. The incidence of CPSP at 3 months after surgery was not reduced in the PVB group compared with the no-block (odds ratio [OR] 0.59, 95% CI 0.34-1.04; p = 0.07; I2 = 6.96%) and other-block (OR 1.39, 95% CI 0.30-6.42; p = 0.67; I2 = 77.75%) groups. The PVB did not significantly reduce the incidence of CPSP after 6 months from surgery when compared with no block (OR 0.44, 95% CI 0.08-2.53; p = 0.36; I2 = 87.53%) and other blocks (OR 1.17, 95% CI 0.71-1.95; p = 0.93; I2 = 45.75%). The PVB significantly decreased postoperative pain at 24 and 48 hours at rest compared with the no- block group. The pain score was higher in the PVB group than in the other block groups 48 hours after surgery at rest. CONCLUSIONS: Thoracic PVB does not prevent CPSP after thoracic surgery. Further large RCTs are required to confirm and validate the authors' results.

The effect of intranasal dexmedetomidine administration on emergence agitation or delirium in pediatric patients after general anesthesia: A meta-analysis of randomized controlled trials.

BACKGROUND: Emergence agitation or delirium can occur in pediatric patients after anesthesia. Dexmedetomidine is known to reduce the impairment of postoperative cognitive function. AIMS: This study aimed to identify the role of intranasal administration of dexmedetomidine in lowering the development of emergence agitation or emergence delirium in pediatric patients after general anesthesia. METHODS: Electronic databases, including PubMed, EMBASE, CENTRAL, Scopus, and Web of Science, were searched to identify studies. The primary outcome was the proportion of patients who underwent emergence agitation or emergence delirium after the surgery. Secondary outcomes included emergence time and incidence of postoperative nausea and/or vomiting. We estimated the odds ratio and mean difference with 95% confidence intervals for the determination of effect size using a random-effects model. RESULTS: In total, 2103 pediatric patients from 20 randomized controlled trials were included in the final analysis. The incidence of emergence agitation or emergence delirium was 13.6% in the dexmedetomidine group and 33.2% in the control group. The pooled effect size revealed that intranasal dexmedetomidine administration significantly reduced the incidence of postoperative emergence agitation or emergence delirium in pediatric patients undergoing surgery under general anesthesia (odds ratio 0.25, 95% confidence interval 0.18-0.34; p = .0000; I2 = 37.74%). Additionally, significant difference was observed in emergence time between the two groups (mean difference 2.42, 95% confidence interval 0.37-4.46; p = .021; I2 = 98.40%). Children in the dexmedetomidine group had a significantly lower incidence of postoperative nausea and/or vomiting than those in the control group (odds ratio 0.39, 95% confidence interval 0.24-0.64; p = .0002; I2 = 0.00%). CONCLUSIONS: Intranasal dexmedetomidine reduced the incidence of emergence agitation or emergence delirium in pediatric patients after general anesthesia.

Intraoperative 5-HT3 receptor antagonists decrease the prevalence of postoperative delirium in older adults undergoing hip fracture surgery: a single-center retrospective study.

PURPOSE: Postoperative delirium (POD) occurs commonly in older adults, resulting in unfavorable outcomes. Several recent clinical studies have suggested that 5-hydroxytryptamine 3 (5-HT3) receptor antagonists can treat and prevent POD. In this retrospective study, the association between 5-HT3 receptor antagonists and POD was investigated in older adults who underwent hip fracture surgery. METHODS: The electronic medical records of older adults aged ≥ 65 years who underwent hip fracture surgery between January 2011 and June 2018 were reviewed retrospectively. Multivariable logistic regression analysis was used to investigate the association between 5-HT3 receptor antagonists and the occurrence of POD. In addition to the incidence of POD, anesthesia-, surgery-, and patient-related factors related to POD were evaluated. RESULTS: Of the 1025 patients included, 813 (79.3%) were administered 5-HT3 receptor antagonists intraoperatively; 471 (45.9%) were administered ramosetron, and 342 (33.4%) were administered palonosetron. POD was identified in 242 patients (23.6%). Ramosetron and palonosetron reduced the POD incidence by 53% (odds ratio [OR] 0.47; 95% confidence interval [CI] 0.32‒0.71; P < 0.001) and 41% (OR 0.59; 95% CI 0.39‒0.89; P = 0.011), respectively. Additionally, age, American Society of Anesthesiologists physical status class 4, and male were confirmed as risk factors for POD. CONCLUSION: Intraoperative 5-HT3 receptor antagonists may be associated with a reduced risk of POD and can be considered one of the preventive strategies for POD in older adults undergoing hip fracture surgery.

Ultrasound assessment of gastric volume in older adults after drinking carbohydrate-containing fluids: a prospective, nonrandomized, and noninferiority comparative study.

PURPOSE: The aim of this study was to evaluate the safety of drinking carbohydrate-containing fluids two hours prior to surgery in older adults using ultrasonography. METHODS: We conducted a nonrandomized and noninferiority comparative study in 60 patients aged over 65 yr who were scheduled for total knee arthroplasty. Patients who were fasted from midnight (fasting group) or who drank 400 mL of a carbohydrate-containing fluid (carbohydrate ingestion group) two hours prior to surgery were matched for age, sex, and body mass index. We measured the cross-sectional area (CSA) of gastric antrum using ultrasound and estimated the gastric fluid volume as the study's primary outcome measure. The noninferiority margin (δ) for the mean difference was predefined as 50 mL. The secondary outcome measures included CSA of the antrum and qualitative gastric volume. RESULTS: The mean (standard deviation) gastric volume was not significantly different between the fasting group and the carbohydrate ingestion group (30.2 [25.4] mL vs 28.4 [35.8] mL; each group, n = 30; P = 0.81). The mean difference in gastric volume was -1.9 mL (95% confidence interval [CI], -17.9 to 14.2), and the upper limit of the 95% CI was lower than the prespecified noninferiority limit (δ = 50 mL). Secondary outcomes were not significantly different between the two groups. CONCLUSION: Drinking of carbohydrate-containing fluid two hours prior to surgery was noninferior to overnight fasting with respect to residual gastric volume at induction of anesthesia in healthy older adults who undergoing total knee arthroplasty. STUDY REGISTRATION: ClinicalTrials.gov (NCT04514380); registered 14 August 2020.

RéSUMé: OBJECTIF: L'objectif de cette étude était d'évaluer l'innocuité de la consommation d'une préparation glucidique deux heures avant une chirurgie chez les personnes âgées à l'aide de l'échographie. MéTHODE: Nous avons mené une étude comparative non randomisée et de non-infériorité chez 60 patients âgés de plus de 65 ans qui devaient bénéficier d'une arthroplastie totale du genou. Les patients étaient à jeun depuis minuit (groupe à jeun) ou avaient bu 400 mL d'une préparation glucidique (groupe d'ingestion de glucides) deux heures avant la chirurgie et ont été appariés pour l'âge, le sexe et l'indice de masse corporelle. Nous avons mesuré la section transversale de l'antre gastrique à l'aide de l'échographie et estimé le volume de liquide gastrique en tant que mesure du critère d'évaluation principal de l'étude. La marge de non-infériorité (δ) pour la différence moyenne a été prédéfinie à 50 mL. Les mesures de critères d'évaluation secondaires comprenaient la section transversale de l'antre et le volume gastrique qualitatif. RéSULTATS: Le volume gastrique moyen (écart type) n'était pas significativement différent entre le groupe à jeun et le groupe d'ingestion de glucides (30,2 [25,4] mL vs 28,4 [35,8] mL; chaque groupe, n = 30; P = 0,81). La différence moyenne de volume gastrique était de -1,9 mL (intervalle de confiance [IC] à 95 %, -17,9 à 14,2), et la limite supérieure de l'IC 95 % était inférieure à la limite de non-infériorité prédéfinie (δ = 50 mL). Aucune différence intergroupe significative n'a été observée dans les critères d'évaluation secondaires. CONCLUSION: La consommation d'une préparation glucidique deux heures avant la chirurgie n'était pas inférieure au jeûne nocturne en ce qui concerne le volume gastrique résiduel à l'induction de l'anesthésie chez les personnes âgées en bonne santé qui bénéficient d'une arthroplastie totale du genou. ENREGISTREMENT DE L'éTUDE: www.ClinicalTrials.gov (NCT04514380); enregistrée le 14 août 2020.

Efficacy of Erector Spinae Plane Block for Analgesia in Thoracic Surgery: A Systematic Review and Meta-Analysis.

OBJECTIVE: The objective of this study was to determine whether erector spinae plane block (ESPB) can provide an effective analgesia for managing pain after thoracic surgery and compare the efficacy of ESPB with that of other regional analgesic techniques. DESIGN: Systematic review and meta-analysis of randomized controlled trials. SETTING: PubMed, EMBASE, CENTRAL, CINAHL, Scopus, and Web of Science were searched. PARTICIPANTS: Patients undergoing thoracic surgeries. INTERVENTION: Erector spinae plane block with local anesthetics for postoperative analgesia. MEASUREMENT AND MAIN RESULTS: Seventeen studies, including 1,092 patients, were included in the final analysis. Erector spinae plane block reduced 24-hour postoperative opioid consumption (mean difference [MD] -17.49, 95% CI -26.87 to -8.12), pain score at rest (MD -0.82, 95% CI -1.31 to -0.33), and pain score at movement (MD -0.77, 95% CI -1.20 to -0.3) compared to no block. Compared with other regional blocks, various results have been observed. Although statistical results showed that ESPB is inferior to thoracic paravertebral block and intercostal nerve block and superior to serratus anterior plan block in postoperative analgesia, clinical differences remain unclear. The incidence of hematoma was lower in the ESPB group than in the other groups (odds ratio 0.19, 95% CI 0.05-0.73). CONCLUSION: Erector spinae plane block may provide effective analgesia after thoracic surgery. Compared with other techniques, it is a safer method, without clinically important differences, for postoperative pain control. Therefore, ESPB may be considered as a valuable option for postoperative pain management after thoracic surgery.

The effects of intraoperative magnesium sulfate administration on emergence agitation and delirium in pediatric patients: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: The role of intraoperative magnesium for the prevention of emergence agitation or delirium is unclear as there have been conflicting results reported by several randomized controlled trials. AIMS: The aim of this study was to investigate the effect of magnesium sulfate on emergence agitation or emergence delirium in pediatric patients. METHODS: Electronic databases, including PubMed, EMBASE, CENTRAL, CINAHL, Scopus, and Web of Science, were searched to identify studies which evaluated the effects of magnesium on postoperative emergence agitation or emergence delirium. The primary outcome was the incidence of emergence agitation or emergence delirium during the post-anesthesia stay. The secondary outcome was the agitation or delirium score upon admission to the post-anesthesia care unit. We estimated the odds ratio and standardized mean difference using a random-effect model. RESULTS: A total of 712 pediatric patients from 10 randomized controlled trials were included in the final analysis. The incidence of emergence agitation or emergence delirium was 29.7% in the magnesium group and 50.5% in the control group. The pooled effect size revealed that the administration of magnesium sulfate significantly reduced the incidence of postoperative emergence agitation or emergence delirium in pediatric patients undergoing surgery with general anesthesia (Odds ratio, 0.31; 95% confidence interval, 0.15 to 0.64; p = .002). Additionally, children in the magnesium group reported significantly lower agitation or delirium scores than those in the control group (standardized mean difference, -0.70; 95% confidence interval, -1.15 to -0.24; p = .003). CONCLUSION: The administration of magnesium sulfate reduced the incidence and severity of emergence agitation or emergence delirium in pediatric patients after the use of general anesthesia during surgery.

Role of Unfolded Protein Response and Endoplasmic Reticulum-Associated Degradation by Repeated Exposure to Inhalation Anesthetics in Caenorhabditis elegans.

Background: When an imbalance occurs between the demand and capacity for protein folding, unfolded proteins accumulate in the endoplasmic reticulum (ER) lumen and activate the unfolded protein response (UPR). In addition, unfolded proteins are cleared from the ER lumen for ubiquitination and subsequent cytosolic proteasomal degradation, which is termed as the ER-associated degradation (ERAD) pathway. This study focused on changes in the UPR and ERAD pathways induced by the repeated inhalation anesthetic exposure in Caenorhabditis elegans. Methods: Depending on repeated isoflurane exposure, C. elegans was classified into the control or isoflurane group. To evaluate the expression of a specific gene, RNA was extracted from adult worms in each group and real-time polymerase chain reaction was performed. Ubiquitinated protein levels were measured using western blotting, and behavioral changes were evaluated by chemotaxis assay using various mutant strains. Results: Isoflurane upregulated the expression of ire-1 and pek-1 whereas the expression of atf-6 was unaffected. The expression of both sel-1 and sel-11 was decreased by isoflurane exposure, possibly indicating the inhibition of retro-translocation. The expression of cdc-48.1 and cdc-48.2 was decreased and higher ubiquitinated protein levels were observed in the isoflurane group than in the control, suggesting that deubiquitination and degradation of misfolded proteins were interrupted. The chemotaxis indices of ire-1, pek-1, sel-1, and sel-11 mutants decreased significantly compared to N2, and they were not suppressed further even after the repeated isoflurane exposure. Conclusion: Repeated isoflurane exposure caused significant ER stress in C. elegans. Following the increase in UPR, the ERAD pathway was disrupted by repeated isoflurane exposure and ubiquitinated proteins was accumulated subsequently. UPR and ERAD pathways are potential modifiable neuroprotection targets against anesthesia-induced neurotoxicity.

Effects of dexmedetomidine on blood coagulation: an in vitro study using rotational thromboelastometry.

PURPOSE: To assess the effects of various concentrations of dexmedetomidine on the human blood coagulation profile using rotational thromboelastometry (ROTEM). METHODS: Venous blood samples were collected from 11 healthy volunteers and divided into four specimen bottles; dexmedetomidine was added to attain final sample concentrations of 0, 0.5, 1.0, and 1.5 ng/mL. ROTEM was performed on each study sample. RESULTS: The concentration of dexmedetomidine increased, and the ROTEM values showed a hypercoagulable state. The change in clotting time (CT) for INTEM was larger in samples with a dexmedetomidine concentration of 1.5 ng/mL (- 34%) than in the 0.5 ng/mL samples (- 16%) (P = 0.010). The change in clot formation time (CFT) for INTEM was greater in 1.5 ng/mL samples (- 16%) than in 0.5 ng/mL samples (- 4%) (P = 0.004). A greater decrease in CT for EXTEM was identified in the 1.0 ng/mL and 1.5 ng/mL samples (- 36% and - 37%, respectively) than in the 0.5 ng/mL samples (- 12%) (P = 0.003 for both categories). The change in CFT for EXTEM was greater in the 1.0 ng/mL and 1.5 ng/mL samples (- 11% and - 13%, respectively) than in the 0.5 ng/mL samples (- 4%) (P = 0.006 and P = 0.001, respectively). A bigger change in maximum clot firmness (MCF) for EXTEM was observed in the 1.5 ng/mL samples (4%) than in the 0.5 ng/mL samples (0%) (P = 0.002). The change in MCF for FIBTEM was greater in the 1.5 ng/mL samples (19%) than in the 0.5 ng/mL samples (5%) (P = 0.001). CONCLUSIONS: All coagulation pathways showed a hypercoagulable state as the concentration of dexmedetomidine increased. Nevertheless, most of the values of ROTEM were maintained within the reference ranges. Clinical Trial NCT04269278.

The Effect of Perioperative Intravenous Iron on Hemoglobin in Surgical Patients: A Meta-Analysis.

BACKGROUND: Patient blood management aims to maintain hemoglobin level, minimize blood loss, and avoid unnecessary blood transfusion. Ferric carboxymaltose, an intravenous iron agent, was included as a part of surgical patient blood management strategy. However, it is still controversial that ferric carboxymaltose can reduce transfusion requirements. The purpose of this systematic review and meta-analysis is to evaluate the benefits of perioperative ferric carboxymaltose on the postoperative hematological parameters and transfusion requirements. METHODS: Randomized controlled trials evaluating the effects of ferric carboxymaltose were searched through databases: MEDLINE, EMBASE, CENTRAL, CINAHL, Scopus, Web of Science, and KoreaMed. Meta-analysis was performed using random effect models. RESULTS: A total of 8 studies (n = 471) were included in the final analysis. Postoperative hemoglobin was higher in the ferric carboxymaltose group than in the control group (mean difference [MD], 0.58 g/dL; 95% confidence interval [CI], 0.36 to 0.80; P < 0.00001). Postoperative serum ferritin and transferrin saturation were also higher in the ferric carboxymaltose group (MD, 373.85 µg/L; 95% CI, 298.13 to 449.56; P < 0.00001; MD, 10.35%; 95% CI, 4.59 to 16.10; P < 0.00001, respectively). However, there were no significant differences in the number of transfused patients, length of hospital stay, and adverse events between groups. Subgroup analysis revealed that adverse events were lower in the ferric carboxymaltose group than the oral iron group. CONCLUSIONS: This study supports that ferric carboxymaltose may increase the postoperative hemoglobin level in surgical patients. However, transfusion requirements could not be reduced by ferric carboxymaltose. Optimal dose and time should be further analyzed.

Comparison of Intraoperative Sedation With Dexmedetomidine Versus Propofol on Acute Postoperative Pain in Total Knee Arthroplasty Under Spinal Anesthesia: A Randomized Trial.

BACKGROUND: In patients undergoing total knee arthroplasty under spinal anesthesia, we compared the postoperative analgesic effect of intraoperative sedation with dexmedetomidine versus propofol. We hypothesized that sedation with dexmedetomidine would result in lower postoperative opioid analgesic consumption than with propofol. METHODS: Forty-eight patients were enrolled and randomly assigned to either a dexmedetomidine group (n = 24), which received a loading dose of 1 µg/kg dexmedetomidine over 10 minutes, followed by a continuous infusion of 0.1-0.5 µg·kg·hour, or a propofol group (n = 24), which received a continuous infusion of propofol via a target-controlled infusion to maintain the effect-site concentration within a range of 0.5-2.0 µg/mL. The drug infusion rate was determined according to the sedation level, targeting a modified observer's assessment of alertness/sedation score of 3 or 4. The cumulative amounts of fentanyl administered via intravenous patient-controlled analgesia were recorded at 24 and 48 hours postoperatively (primary outcome). The postoperative numerical rating scale for pain was assessed at 6, 12, 24, and 48 hours (secondary outcome). The postoperative use of additional rescue analgesic (ketoprofen) and antiemetic drugs was also compared between the 2 groups at 24 and 48 hours. RESULTS: Dexmedetomidine significantly reduced postoperative fentanyl consumption (median [interquartile range]) during 0-24 hours (45 [30-71] vs 150 [49-248] µg, P = .004; median difference = -105 µg [99.98% CI, 210-7.5]), 24-48 hours (90 [45-143] vs 188 [75-266] µg, P = .005; median difference = -98 µg [99.98% CI, 195-45]), and 0-48 hours (135 [68-195] vs 360 [146-480] µg, P = .003; median difference = -225 µg [99.98% CI, 405-7.5]). The numerical rating scale (median [interquartile range]) was lower at 6 hours (1 [0-2] vs 2 [1-3], P = .003), 12 hours (1 [1-2] vs 3 [2-3], P < .001), 24 hours (1 [1-2] vs 3 [2-3], P < .001), and 48 hours (2 [2-3] vs 3 [3-4], P < .001) after surgery in the dexmedetomidine group compared to the propofol group. No significant intergroup differences were observed in the amount of rescue analgesics and antiemetics at 24 hours (P = .155 and P = .482) and 48 hours (P = .082 and P = .153) after surgery. CONCLUSIONS: Intraoperative dexmedetomidine sedation was associated with a small but clinically important reduction in postoperative opioid use after total knee arthroplasty.

Detecting affiliation in colaughter across 24 societies.

Laughter is a nonverbal vocal expression that often communicates positive affect and cooperative intent in humans. Temporally coincident laughter occurring within groups is a potentially rich cue of affiliation to overhearers. We examined listeners' judgments of affiliation based on brief, decontextualized instances of colaughter between either established friends or recently acquainted strangers. In a sample of 966 participants from 24 societies, people reliably distinguished friends from strangers with an accuracy of 53-67%. Acoustic analyses of the individual laughter segments revealed that, across cultures, listeners' judgments were consistently predicted by voicing dynamics, suggesting perceptual sensitivity to emotionally triggered spontaneous production. Colaughter affords rapid and accurate appraisals of affiliation that transcend cultural and linguistic boundaries, and may constitute a universal means of signaling cooperative relationships.

A Comparison of Hemostatic Properties between Monopolar and Bipolar Hysteroscopic Surgery using Rotational Thromboelastometry: A Randomized Trial.

OBJECTIVE: Systemic absorption of irrigation fluid can lead to a disturbed coagulation cascade. We compared the changes in hemostatic properties on using nonelectrolyte solution in monopolar hysteroscopic surgery (HS) with that on using isotonic saline in bipolar HS via rotational thromboelastometry (ROTEM) analysis. METHODS: A total of 54 patients were randomized into 2 groups: 1 group underwent monopolar HS using a mixture of 2.7% sorbitol and 0.54% mannitol (the HSMP group), whereas the other group underwent bipolar HS using 0.9% isotonic saline (the HSBP group). The effects of these 2 methods on coagulation were assessed via pre and postoperative laboratory tests, including estimation of the international normalized ratio of prothrombin time and activated partial thromboplastin time and ROTEM analysis. In addition, the hemoglobin, hematocrit, and electrolyte levels and the platelet count were analyzed. RESULTS: Patient characteristics, volume of irrigation fluid absorbed, and type of procedure were comparable between the 2 groups. There were no significant differences in the pre and postoperative values of ROTEM parameters between the 2 groups. Most postoperative ROTEM parameters, as compared with preoperative values, changed in both groups; clot formation time was prolonged, and the α-angle and maximum clot firmness were decreased. All ROTEM parameters were maintained within the normal range. Hematological parameters, including hemoglobin and hematocrit levels and platelet count, were significantly decreased postoperatively in both groups compared to the preoperative values. No pre and postoperative hematological and hemostatic parameters were significantly different between the 2 groups. CONCLUSION: Irrigation fluid absorbed in healthy women during HS caused hypocoagulable changes in the blood, irrespective of the irrigant type, and no significant differences between HS using monopolar and bipolar electrodes were demonstrated.

The Perception of Spontaneous and Volitional Laughter Across 21 Societies.

Laughter is a nonverbal vocalization occurring in every known culture, ubiquitous across all forms of human social interaction. Here, we examined whether listeners around the world, irrespective of their own native language and culture, can distinguish between spontaneous laughter and volitional laughter-laugh types likely generated by different vocal-production systems. Using a set of 36 recorded laughs produced by female English speakers in tests involving 884 participants from 21 societies across six regions of the world, we asked listeners to determine whether each laugh was real or fake, and listeners differentiated between the two laugh types with an accuracy of 56% to 69%. Acoustic analysis revealed that sound features associated with arousal in vocal production predicted listeners' judgments fairly uniformly across societies. These results demonstrate high consistency across cultures in laughter judgments, underscoring the potential importance of nonverbal vocal communicative phenomena in human affiliation and cooperation.

Comparison of upper airway patency in patients with mild obstructive sleep apnea during dexmedetomidine or propofol sedation: a prospective, randomized, controlled trial.

BACKGROUND: In addition to propofol, dexmedetomidine is a suitable alternative for intraoperative sedation in procedures requiring regional anesthesia. To date, however, little is known about the influences of each drug on upper airway patency. Accordingly, the authors investigated differences between dexmedetomidine and propofol sedation in the occurrence of upper airway obstruction and requirements for airway intervention in patients with mild obstructive sleep apnea. METHODS: Patients with an apnea/hypopnea index of 5-14/h according to Watch-PAT 200 analysis were enrolled in this study. Spinal anesthesia was routinely performed for surgery. Intraoperative sedation was initiated using either dexmedetomidine or propofol infusion at a level of modified observer's assessment of alertness/sedation scale 3. The primary outcome was the proportion of patients exhibiting signs of upper airway obstruction. A sign of upper airway obstruction was defined as no detection of end-tidal carbon dioxide for at least 10 s despite respiratory efforts. RESULTS: A total of 50 patients were included in the final analysis (dexmedetomidine [n = 26]; propofol [n = 24]). During the intraoperative sedation period, there was a significantly lower proportion of patients exhibiting signs of upper airway obstruction in the dexmedetomidine group than in the propofol group (11.5% vs. 41.7%, P = 0.035). An artificial airway was inserted in 1 patients (3.8%) and 5 patient (20.8%) in the dexmedetomidine and propofol groups, respectively (P = 0.093). CONCLUSION: Dexmedetomidine sedation was associated with a lower incidence of upper airway obstruction than propofol sedation in patients with mild obstructive sleep apnea. TRIAL REGISTRATION NUMBER: Clinical trials.gov ( NCT02993718 ): Retrospectively registered.

The Role of Perioperative Statin Use in the Prevention of Delirium After Total Knee Replacement Under Spinal Anesthesia.

BACKGROUND: The relationship between statin use and incidence of postoperative delirium (POD) is controversial. We investigated the association between perioperative statin use and occurrence of delirium after total knee arthroplasty (TKA) under spinal anesthesia. METHODS: We retrospectively reviewed the electronic medical records of patients who underwent TKA under spinal anesthesia at a single tertiary care hospital between January 2005 and October 2017. POD incidence was recorded for patients who received statins continuously from 1 month before surgery until discharge and for patients who did not receive any statins. Univariable and multivariable logistic regression analyses were conducted to investigate an association between occurrence of POD and perioperative statin use. RESULTS: In total, 6020 procedures were included, and 992 (16.4%) were associated with perioperative statin use. POD was confirmed for 304 (5.0%) procedures. The statin group showed a 1.7% significant lower incidence (P = .017) of POD (35/992, 3.5%) than the no statin group (1420/5,028, 5.4%). In multivariable logistic regression analysis, the POD incidence in the statin group was 34% lower than that in the no statin group (odds ratio [OR] 0.66, 95% confidence interval [CI] 0.45-0.97, P = .036]. Moreover, the POD incidence was decreased by 37% (OR 0.63, 95% CI 0.40-0.99, P = .047) and 79% (OR 0.21, 95% CI 0.05-0.88, P = .033) respectively, when atorvastatin and simvastatin were administered. CONCLUSION: Continuous perioperative statin use may be associated with a significantly lower risk of delirium after TKA under spinal anesthesia; simvastatin was the most effective statin for POD prevention.

Continuous wound infiltration system for postoperative pain management in gynecologic oncology patients.

PURPOSE: Major open surgery for gynecologic cancer usually involves a long midline skin incision and induces severe postoperative surgical site pain (POSP) that may not be effectively controlled with the conventional management. We investigated whether combining a continuous wound infiltration system (CWIS, ON-Q PainBuster®) and intravenous patient-controlled analgesia (IV PCA) effectively decreases POSP, compared with IV PCA alone, in gynecologic oncology patients. METHODS: This retrospective study included 62 Korean patients who received a long midline skin incision during gynecologic cancer surgery. The combined therapy group (n = 31), which received CWIS (0.5% ropivacaine infused over 72 h) and IV PCA (fentanyl citrate), and the IV PCA only group (n = 31) were determined using 1:1 matching. POSP was assessed using resting numeric rating scale (NRS) scores measured for 96 h after surgery, which were analyzed using a linear mixed model. RESULTS: The slopes of the predicted NRS values from the linear mixed model were significantly different between the groups. Compared with the control group, the combined therapy group had lower predicted NRS scores for the first 72 h, but higher predicted scores between 72 and 96 h. Moreover, the mean NRS scores over the first 48 h postoperation were significantly lower in the combined therapy group than in the control group; the scores were similar in both groups during the remaining period. With the exception of a higher body mass index in the CWIS group, the other variables, such as the dosage and usage time of fentanyl citrate, use of additional painkillers, and side effects, including wound complications, did not differ between groups. CONCLUSIONS: Combined therapy using CWIS and IV PCA may be a useful strategy for POSP management in gynecologic oncology patients.