The effect of non-steroidal anti-inflammatory drugs on postoperative delirium: a meta-analysis.

Background: Neuroinflammation is postulated as a potential mechanism underlying postoperative delirium. This study aimed to investigate the impact of non-steroidal anti-inflammatory drug (NSAID) use on postoperative delirium. Methods: We conducted a literature search in electronic databases, including PubMed, EMBASE, CENTRAL, and Web of Science, to identify eligible randomized controlled studies. The primary outcome was the incidence of postoperative delirium, and the secondary outcomes included pain scores and the amounts of opioid used at 24 h postoperatively. We estimated the effect size through calculating the odds ratios (ORs) or mean differences (MDs) with 95% CIs, as appropriate. Results: In the analysis of eight studies involving 1,238 participants, the incidence of postoperative delirium was 11% and 19% in the NSAID and control groups, respectively, with a significant reduction in the NSAID group (OR, 0.54; 95% CI, 0.38 to 0.76; P = 0.0001; I2 = 0%). NSAID use had a significant effect on postoperative pain reduction (MD, -0.75; 95% CI, -1.37 to -0.13; P = 0.0172; I2 = 88%). Significant lower postoperative opioid consumption was observed in the NSAID group (MD, -2.88; 95% CI, -3.54 to -2.22; P = 0.000; I2 = 0%). Conclusions: NSAID administration reduced the incidence of postoperative delirium, severity of pain, and opioid dose used.

Preoperative gastric volume assessment using ultrasound in cerebral palsy pediatric patients: a prospective observational study.

BACKGROUND: Although cerebral palsy is a risk factor for aspiration, there is insufficient research on residual gastric volume after preoperative fasting in children with cerebral palsy. We evaluated the incidence of a full stomach by ultrasound assessment of the gastric volume in children with cerebral palsy who underwent orthopedic surgery after preoperative fasting. METHODS: The patients fasted for 8 h for solid foods and 2 h for clear liquids. We obtained the gastric antral cross-sectional area using ultrasound in the semi-recumbent and right lateral decubitus positions. A calculated stomach volume > 1.5 mL.kg-1 was considered as full, which poses a high aspiration risk. The primary outcome was the incidence of full stomach, and the secondary outcomes were the qualitative gastric volume, correlation of disease severity categorized according to the Gross Motor Function Classification System with the residual gastric volume, gastric volume per body weight, and qualitative gastric volume. RESULTS: Thirty-seven pediatric patients with cerebral palsy, scheduled for elective orthopedic surgery, were included for analysis. Full-stomach status was observed in none, and the gastric volume per body weight was 0.5 (0.4-0.7) mL.kg-1. No significant differences were observed in the residual gastric volume (p = 0.114), gastric volume per body weight (p = 0.117), or qualitative grade of gastric volume (p = 0.642) in relation to disease severities. CONCLUSION: Children with cerebral palsy who fasted preoperatively had empty or nearly empty stomachs. Further studies are required to determine the optimal fasting duration for such children.

Neuroprotective effect of erythropoietin on anesthesia-induced neurotoxicity through the modulation of autophagy in Caenorhabditis elegans.

BACKGROUND: The anti-oxidative, anti-inflammatory, and anti-apoptotic effects of erythropoietin may provide neuroprotective effects. Erythropoietin also modulates autophagy signaling that may play a role in anesthesia-induced neurotoxicity (AIN). Herein, we investigated whether AIN can be attenuated by the neuroprotective effect of erythropoietin in the Caenorhabditis elegans (C. elegans). METHODS: Synchronized worms were divided into the control, Iso, EPO, and EPO-Iso groups. The chemotaxis index (CI) was evaluated when they reached the young adult stage. The lgg-1::GFP-positive puncta per seam cell were used to determine the autophagic events. The erythropoietin-mediated pathway of autophagy was determined by measuring the genetic expression level of let-363, bec-1, atg-7, atg-5, and lgg-3. RESULTS: Increased lgg-1::GFP puncta were observed in the Iso, EPO, and EPO-Iso groups. In the Iso group, only the let-363 level decreased significantly as compared to that in the control group (P = 0.009). bec-1 (P < 0.001), atg-5 (P = 0.012), and lgg-3 (P < 0.001) were expressed significantly more in the EPO-Iso group than in the Iso groups. Repeated isoflurane exposure during development decreased the CI. Erythropoietin could restore the decreased CI by isoflurane significantly in the EPO-Iso group. CONCLUSIONS: Erythropoietin showed neuroprotective effects against AIN and modulated the autophagic pathway in C. elegans. This experimental evidence of erythropoietin-related neuroprotection against AIN may be correlated with the induced autophagic degradation process that was sufficient for handling enhanced autophagy induction in erythropoietin-treated worms.

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 analgesic effects of the quadratus lumborum block in pediatric patients: a systematic review and meta-analysis.

Background: This study assessed the postoperative analgesic efficacy and safety of the quadratus lumborum block (QLB) in pediatric patients. Methods: Electronic databases were searched for studies comparing the QLB to conventional analgesic techniques in pediatric patients. The primary outcome was the need for rescue analgesia 12 and 24 hours after surgery. Secondary outcomes covered the Face-Legs-Activity-Cry-Consolability Scale (FLACC) scores at various time points; parental satisfaction; time to the first rescue analgesia; hospitalization time; block execution time; block failure rates, and adverse events. Results: Sixteen randomized controlled trials were analyzed involving 1,061 patients. The QLB significantly reduced the need for rescue analgesia both at 12 and 24 hours after surgery (12 hours, relative risk [RR]: 0.45; 95% confidence interval [CI]: 0.01, 0.88; 24 hours, RR: 0.51; 95% CI: 0.31, 0.70). In case of 24 hours after surgery, type 1 QLB significantly reduced the need for rescue analgesia (RR: 0.56; 95% CI: 0.36, 0.76). The QLB also exhibited lower FLACC scores at 1 hour (standardized mean difference [SMD]: -0.87; 95% CI: -1.56, -0.18) and 6 hours (SMD: -1.27; 95% CI: -2.33, -0.21) following surgery when compared to non-QLB. Among QLBs, type 2 QLB significantly extended the time until the first rescue analgesia (SMD: 1.25; 95% CI: 0.84, 1.67). No significant differences were observed in terms of parental satisfaction, hospitalization time, block execution time, block failure, or adverse events between QLB and non-QLB groups. Conclusions: The QLB provides non-inferior analgesic efficacy and safety to conventional methods in pediatric patients.

The Impact of Regional Nerve Blocks on Postoperative Delirium or Cognitive Dysfunction following Thoracic Surgery: A Systematic Review and Meta-Analysis.

Regional nerve blocks (NBs) mitigate the occurrence of postoperative cognitive dysfunction (POCD) and postoperative delirium (POD) in adult patients undergoing thoracic surgery. This study aimed to determine the exact effect of NBs on POCD and POD. Electronic databases, including PubMed, EMBASE, CINAHL, Scopus, and Web of Science, were searched for studies. The primary outcome was the incidence of POD or POCD. The secondary outcome was pain scores assessed 24 and 48 h postoperatively. We calculated the log odds ratio (LOR) and standardized mean difference (SMD) with 95% confidence intervals (CIs). The LOR was converted to an odds ratio (OR). In the analysis of 1010 patients from seven randomized controlled trials, POD and POCD rates were 14.1% and 16.7%, respectively, in the NB group, and higher, at 27.3% and 35.2%, in the control group. NBs reduced the incidence of POD (OR, 0.44; 95%CI 0.30 to 0.64; p < 0.001; I2 = 0.00%) and POCD (OR, 0.43; 95%CI 0.24 to 0.76; p < 0.001; I2 = 0.00%). NBs reduced pain scores at 24 h (SMD, -2.60; 95%CI -3.90 to -1.30, p < 0.001; I2 = 97.68%) and 48 h (SMD, -1.80; 95%CI -3.18 to -0.41, p = 0.01; I2 = 98.14%) postoperatively. NBs mitigated the occurrence of POD and POCD in adult patients after thoracic surgery.

Effects of magnesium sulphate on neostigmine-induced recovery from moderate neuromuscular blockade with rocuronium: a randomized controlled trial.

Magnesium enhances the effects of neuromuscular blocking agents. However, there is a paucity of evidence demonstrating possible effects of magnesium on neostigmine-induced recovery from neuromuscular blockade with rocuronium. This study compared the profiles of recovery from neuromuscular blockade between groups treated with magnesium (Group M) and placebo controls (Group C). Sixty-four patients were randomly allocated to Group M or Group C. Patients in Group M received a loading dose of 50 mg/kg magnesium and continuous infusion of 15 mg/kg/hr. Patients in Group C received a comparable amount of saline. Rocuronium at 0.6 mg/kg was used for tracheal intubation and 0.1 mg/kg of rocuronium was additionally administered to maintain train-of-four (TOF) status of 2-3 during surgery. At the end of surgery, neostigmine (50 µg/kg) plus glycopyrrolate (10 µg/kg) were administered, and the recovery time for TOF ratios of 0.7, 0.8, and 0.9 was measured. The primary outcome was the time from neostigmine administration to recovery with a TOF ratio of 0.9. In addition, rocuronium onset time (time from administration of rocuronium to 95% suppression of the first TOF twitch response), additional requirements for rocuronium and spontaneous recovery period (the time from administration of rocuronium to reappearance of the first TOF twitch response) were also measured. Neostigmine-induced recovery time was comparable between Group M and Group C (10.6 ± 4.3 vs. 9.1 ± 5.0 min, respectively, p = 0.22). The rocuronium onset time was shorter in Group M, and the spontaneous recovery period was longer in Group M. The amount of additional rocuronium administered was 27% lower in Group M, but this difference was not significant. Magnesium was not shown to prolong neostigmine-induced recovery time from neuromuscular blockade with rocuronium, however, it enhanced the clinical effects of rocuronium.

Hemidiaphragmatic paralysis after costoclavicular approach versus other brachial plexus blocks in upper limb surgery: a meta-analysis.

BACKGROUND: The costoclavicular brachial plexus block (CCB) is a recently established technique that uses the infraclavicular approach and is performed just below the clavicle. This meta-analysis aimed to determine whether CCB can reduce the incidence of hemidiaphragmatic paralysis (HDP), which is a major adverse event related to brachial plexus block (BPB), while yielding comparable block performance as other BPB techniques. METHODS: We searched electronic databases to identify relevant studies that compared the incidence of HDP between CCB and other BPB techniques. The primary outcome was the incidence of HDP following CCB and other BPB techniques. The secondary outcomes were pulmonary function test results, other adverse events, and block performance parameters such as onset and performance time. RESULTS: We included six randomized controlled trials that included 414 patients. Compared with the other BPB group, the CCB group had a significantly lower incidence of HDP (relative ratio: 0.21, 95% CI [0.12, 0.36], P < 0.001) and higher peak expiratory flow rate (mean difference: 0.68 L/s, 95% CI [0.13, 1.23], P = 0.015). There were no significant between-group differences with respect to other adverse events and block performance parameters. CONCLUSIONS: Compared with other BPB techniques, CCB involves a lower incidence of HDP with comparable onset and performance time.

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.

The Effect of Peripheral Nerve Block on Postoperative Delirium in Older Adults Undergoing Hip Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

This meta-analysis aimed to determine whether peripheral nerve blocks (PNB) reduce postoperative delirium (POD) in elderly patients undergoing hip surgery. This study was registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD42022328320). The PubMed, EMBASE, Web of Science, and Cochrane Library databases were searched for randomized controlled trials (RCTs) on 26 April 2022. A total of 19 RCTs with 1977 participants were included. Perioperative PNB lowered the POD incidence on the third postoperative day (OR: 0.59, 95% CI [0.40 to 0.87], p = 0.007, I2 = 35%), in patients without underlying cognitive impairment (OR: 0.47, 95% CI [0.30 to 0.74], p = 0.001, I2 = 30%), and when a fascia iliaca compartment block (OR: 0.58, 95% CI [0.37 to 0.91], p = 0.02, I2 = 0%) or a femoral nerve block (OR: 0.33, 95% CI [0.11 to 0.99], p = 0.05, I2 = 66%) were performed. The pain score was also reduced (SMD: -0.83, 95% CI [-1.36 to -0.30], p = 0.002, I2 = 95%) after PNB. Perioperative PNB can lower the POD incidence and pain scores up to the third postoperative day. However, considering the wide variety of PNBs performed, more trials are needed to identify the effects of each PNB on POD.

Change in glottic view during intubation using a KoMAC videolaryngoscope: A retrospective analysis.

Intubation with videolaryngoscopy has become popular in various clinical settings. However, despite the use of a videolaryngoscope, difficult intubation still exists and intubation failure has been reported. This retrospective study assessed the efficacy of the 2 maneuvers in improving the glottic view during videolaryngoscopic intubation. The medical records of patients who underwent videolaryngoscopic intubation and whose glottal images were stored in electronic medical charts were reviewed. The videolaryngoscopic images were divided into 3 categories according to the applied optimization techniques as follows: conventional method, with the blade tip located in the vallecular; backward-upward-rightward pressure (BURP) maneuver; and epiglottis lifting maneuver. Four independent anesthesiologists scored the visualization of the vocal folds using the percentage of glottic opening (POGO, 0-100%) scoring system. A total of 128 patients with 3 laryngeal images were analyzed. The glottic view was the most improved in the epiglottis lifting maneuver among all the techniques. The median POGO scores were 11.3, 36.9, and 63.1 in the conventional method, BURP, and epiglottis lifting maneuver, respectively (P < .001). There were significant differences in the distribution of POGO grades according to the application of BURP and epiglottis lifting maneuvers. In the POGO grades 3 and 4 subgroups, the epiglottis lifting maneuver was more effective than the BURP maneuver in improving the POGO score Inadequate visualization of the vocal folds occurred even when intubation was performed using a videolaryngoscope. The application of optimization maneuvers, such as BURP and epiglottis lifting by the blade tip, could improve the glottic view.

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.

Polymer Electrolyte/Sulfur Double-Shelled Anisotropic Reduced Graphene Oxide Lamellar Scaffold Enables Stable and High-Loading Cathode for Quasi-Solid-State Lithium-Sulfur Batteries.

Lithium-sulfur batteries (LSBs) can replace lithium-ion batteries by delivering a higher specific capacity. However, the areal capacity of current LSBs is low because the intrinsic limitations of sulfur make achieving a high sulfur loading difficult. Herein, the authors report vertically aligned reduced graphene oxide (rGO) with sulfur and poly(ethylene oxide)-based polymer electrolyte double-shell layers (VRG@S@PPE) as a high-loading sulfur cathode. The addition of vapor-grown carbon fiber (VGCF) into rGO is the key to success, as it allows for gas evacuation from internal nano/micropores without structural collapse, enabling perfect double-shell layer contact. Owing to the anisotropic rGO lamellar structure that enables straightforward ion/electron transport and provides numerous active sites, sulfur-infiltrated rGO reinforced via VGCF (VRG@S) exhibits a high capacity of 998 mAh g-1 after 100 cycles at 0.1 C under high sulfur loading (6 mg cm-2 ). Interestingly, an additional polymer electrolyte layer further increases the cycle retention (1005 and 718 mAh g-1 after 100 cycles at 0.1 and 1 C, respectively), because intimate contact between the solid polymer electrolyte and sulfur could suppress the loss of sulfur due to lithium polysulfide (LPS) shuttling or volume change during lithiation/delithiation. Therefore, it is possible to realize safe and stable quasi-solid-state LSBs with high sulfur loading.

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.

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 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.

Ultrasound assessment of residual gastric volume in older adults undergoing staged-bilateral total knee arthroplasty after consuming carbohydrate-containing fluids: a prospective observational study.

BACKGROUND: We compared preoperative residual gastric volume (GV) between the first and second stages of total knee arthroplasty (TKA) in older adults after drinking carbohydrate-containing fluid 2 h prior to surgery. METHODS: In this study, 36 patients, aged > 65 years, scheduled for staged bilateral TKA with one-week interval, were enrolled. The patients consumed 400 ml of carbohydrate-containing fluid 2 h prior to surgery. Before the induction of spinal anesthesia, the gastric antral cross-sectional area was measured at the first and second TKA using ultrasound, and the residual GV was calculated. The primary outcome was the residual GV. Qualitative GV (grades 0, 1, and 2) and analgesic consumption after the first TKA were assessed as secondary outcomes. RESULTS: The GV (median [Q1, Q3]) was greater in the second-stage TKA (41.1 [22.5, 62.8] ml) than in the first-stage TKA (10.3 [0.0, 27.1] ml) (P < 0.001). In the qualitative assessment, the distribution was not different between the two stages of TKA (P = 0.219) and only one patient showed grade 2 gastric content in the second TKA. When opioid consumption was converted to an equivalent dose of morphine, an average of 53.9 mg of morphine was required after the first TKA. CONCLUSIONS: Residual GV after drinking carbohydrate-containing fluid differed according to the stage of TKA, showing a larger residual GV in the second TKA than in the first one. In older adults scheduled to undergo bilateral staged TKA, caution is required in preoperative fasting practice, especially in second-stage surgery.

Incidence of ionized hypomagnesemia in adult patients undergoing noncardiac major surgery: a prospective observational trial

Background: The present study aimed to investigate the incidence of preoperative ionized hypomagnesemia and compare with that of total hypomagnesemia. Methods: This prospective observational study included 536 patients aged >20 years who were scheduled for elective surgery. Total and ionized magnesium levels were evaluated before and after the surgery. Based on these levels, patients were classified into the following groups: ionized hypo- (<0.42 mmol/L), normo- (0.42-0.59 mmol/L) and hypermagnesemia (>0.59 mmol/L), as well as total hypo- (<1.9 mg/dL[0.78 mmol/L]), normo- (1.9-2.7 mg/dL[0.78-1.11 mmol/L]) and hypermagnesemia (>2.7 mg/dL [1.11 mmol/L]). The primary objective was to establish the incidence of preoperative ionized hypomagnesemia. Results: There was a marked difference between the incidence of preoperative ionized and total hypomagnesemia (28% vs. 19%; p<0.001). The postoperative values of ionized magnesium, ionized calcium, and albumin were significantly lower than the respective preoperative values (p<0.001 for all three variables). Conclusion: The incidence of hypomagnesemia, determined by ionized magnesium concentration, was higher than that determined by total magnesium concentration.

The effect of lidocaine patch for postoperative pain: A meta-analysis of randomized controlled trials.

STUDY OBJECTIVE: The role of lidocaine patch (LP) in reducing postoperative pain by local anesthetic absorption has been evaluated in several studies; however, these trials have shown inconsistent results. This meta-analysis aimed to identify the benefits of LP, focusing on its pain-reducing and morphine-sparing effect in patients after surgery. DESIGN: Meta-analysis. SETTING: Published randomized controlled trials (RCTs) comparing the analgesic effects of LP after surgery to those of placebo or no patch. PATIENTS: Eleven RCTs including 539 patients. INTERVENTIONS: We searched electronic databases to identify relevant RCTs. MEASUREMENTS: The primary outcome was postoperative pain score up to 48 h assessed using a numerical rating or visual analog scale, and the secondary outcomes were postoperative morphine consumption and side effects. The effect size was estimated by calculating the mean difference (MD) or risk ratio (RR), with 95% confidence interval (CI). MAIN RESULTS: LP significantly decreased postoperative pain score at 6 h (MD, -1.85; 95% CI, -2.98 to -0.72; p = 0.001), 12 h (MD, -1.48; 95% CI, -2.07 to -0.88; p < 0.001), 24 h (MD, -1.18; 95% CI, -1.65 to -0.7; p < 0.001), and 48 h (MD, -1.33; 95% CI, -2.46 to -0.19; p = 0.022). In contrast, no significant effect on postoperative morphine consumption was observed at 24 h (MD, -3.48 mg; 95% CI, -7.94 to 0.98 mg; p = 0.127) or 48 h (MD, -5.29 mg; 95% CI, -13.28 to 2.71; p = 0.195). LP was unrelated to local (RR, 1.00, 95% CI, 0.67 to 1.49; p = 0.987) or systemic side effects (RR, 0.76, 95% CI, 0.52 to 1.11, p = 0.151). CONCLUSIONS: LP can lower postoperative pain without side effects, compared to placebo or no patch. However, its morphine-sparing effect remains unclear.