Outcome of Organ Dysfunction in the Perioperative Period

Predicting the Risk of Postoperative Delirium in Elderly Patients Undergoing Hip Arthroplasty: Development and Assessment of a Novel Nomogram

OBJECTIVE

To construct and internally validate a nomogram that predicts the likelihood of postoperative delirium in a cohort of elderly individuals undergoing hip arthroplasty.

METHODS

Data for a total of 681 elderly patients underwent hip arthroplasty were retrospectively collected and divided into a model (n = 477) and a validation cohort (n = 204) according to the principle of 7:3 distribution temporally. The assessment of postoperative cognitive function was conducted through the utilization of The Confusion Assessment Method (CAM). The nomogram model for postoperative cognitive impairments was established by a combination of Lasso regression and logistic regression. The receiver operating characteristic (ROC) curve, calibration plot, and decision curve analysis (DCA) were used to evaluate the performance.

RESULTS

The nomogram utilized various predictors, including age, body mass index (BMI), education, preoperative Barthel Index, preoperative hemoglobin level, history of diabetes, and history of cerebrovascular disease, to forecast the likelihood of postoperative delirium in patients. The area under the ROC curves (AUC) for the nomogram, incorporating the aforementioned predictors, was 0.836 (95% CI: 0.797-0.875) for the training set and 0.817 (95% CI: 0.755-0.880) for the validation set. The calibration curves for both sets indicated a good agreement between the nomogram's predictions and the actual probabilities.

CONCLUSION

The use of this novel nomogram can help clinicians predict the likelihood of delirium after hip arthroplasty in elderly patients and help prevent and manage it in advance.

Teaching Before, During, and After a Surgical Resuscitation

Teaching during a surgical resuscitation can be difficult due to the infrequency of these events. Furthermore, when these events do occur, the trainee can experience cognitive overload and an overwhelming amount of stress, thereby impairing the learning process. The emergent nature of these scenarios can make it difficult for the surgical educator to adequately teach. Repeated exposure through simulation, role play, and "war games" are great adjuncts to teaching and preparation before crisis. However, surgical educators can further enhance the knowledge of their trainees during these scenarios by using tactics such as talking out loud, targeted teaching, and debriefing.

Dietary Restriction Improves Perioperative Neurocognitive Disorders by Inhibiting Neuroinflammation and Gut Microbial Dysbiosis

Anesthesia/surgery have been identified as potential factors contributing to perioperative neurocognitive disorders, with a notably heightened risk observed in aging populations. One of the primary drivers of this impairment is believed to be neuroinflammation, specifically inflammation of hippocampal microglia. Dietary restriction has demonstrated a favorable impact on cognitive impairment across various disorders, primarily by quelling neuroinflammation. However, the precise influence of dietary restriction on perioperative neurocognitive disorders remains to be definitively ascertained. This investigation aims to explore the effects of dietary restriction on perioperative neurocognitive disorders and propose innovative therapeutic strategies for their management. The model of perioperative neurocognitive disorder was induced through exploratory laparotomy under isoflurane anesthesia. Cognitive performance was evaluated using the open field test, Barnes maze test, and fear conditioning test. The enzyme-linked immunosorbent assay (ELISA) was employed to quantify concentrations of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) in both serum and hippocampal samples. The Western blot technique was utilized to assess expression levels of hippocampal PSD 95, Synaptophysin, TLR4, MyD88, and NF-kB p65. Microglial polarization was gauged using a combination of reverse transcription quantitative polymerase chain reaction (RT-qPCR) and immunofluorescence labeling techniques. We conducted 16S rRNA sequencing to investigate the impact of dietary restriction on the intestinal flora of aged mice following anesthesia/surgery. Our findings indicate that dietary restrictions have the potential to ameliorate anesthesia/surgery-induced cognitive dysfunction. This effect is achieved through the modulation of gut microbiota, suppression of inflammatory responses in hippocampal microglia, and facilitation of neuronal repair and regeneration.

Nomogram for predicting postoperative pulmonary complications in spinal tumor patients

OBJECTIVES

Although several independent risk factors for postoperative pulmonary complications (PPCs) after spinal tumor surgery have been studied, a simple and valid predictive model for PPC occurrence after spinal tumor surgery has not been developed.

PATIENTS AND METHODS

We collected data from patients who underwent elective spine surgery for a spinal tumor between 2013 and 2020 at a tertiary hospital in China. Data on patient characteristics, comorbidities, preoperative examinations, intraoperative variables, and clinical outcomes were collected. We used univariable and multivariable logistic regression models to assess predictors of PPCs and developed and validated a nomogram for PPCs. We evaluated the performance of the nomogram using the area under the receiver operating characteristic curve (ROC), calibration curves, the Brier Score, and the Hosmer-Lemeshow (H-L) goodness-of-fit test. For clinical use, decision curve analysis (DCA) was conducted to identify the model's performance as a tool for supporting decision-making.

RESULTS

Among the participants, 61 (12.4%) individuals developed PPCs. Clinically significant variables associated with PPCs after spinal tumor surgery included BMI, tumor location, blood transfusion, and the amount of blood lost. The nomogram incorporating these factors showed a concordance index (C-index) of 0.755 (95% CI: 0.688-0.822). On internal validation, bootstrapping with 1000 resamples yielded a bias-corrected area under the receiver operating characteristic curve of 0.733, indicating the satisfactory performance of the nomogram in predicting PPCs. The calibration curve demonstrated accurate predictions of observed values. The decision curve analysis (DCA) indicated a positive net benefit for the nomogram across most predicted threshold probabilities.

CONCLUSIONS

We have developed a new nomogram for predicting PPCs in patients who undergo spinal tumor surgery.

Effect of remote ischemic preconditioning on postoperative cognitive dysfunction in adult patients with general anesthesia: a meta-analysis

BACKGROUND

Remote ischemic preconditioning (RIPC) is proven to have neuroprotective protective effects. Nevertheless, the impact of RIPC on postoperative cognitive dysfunction (POCD) in patients undergoing general anesthesia is controversial. This meta-analysis of randomized controlled trials (RCTs) aimed to assess the effect of RIPC on POCD in adults after general anesthesia.

METHODS

Relevant literature was obtained by searching Embase, PubMed, Web of Science, Cochrane Library, Wanfang, and China National Knowledge Infrastructure (CNKI) databases in July 2022. RCTs were included to assess the influences of RIPC on POCD in adults following general anesthesia. Two investigators independently performed literature screening, data extraction, and quality assessment based on the inclusion and exclusion criteria. The incidence of POCD, operation time, and hospital stay were analyzed by Review manager5.4 software.

RESULTS

Thirteen RCTs with 1122 participants were selected for this meta-analysis. Compared to the control group, RIPC decreased the incidence of POCD (OR = 0.50, 95% CI 0.31-0.82), as well as reduced the duration of hospitalization (MD = - 0.98, 95% CI - 1.69 to - 0.27), but did not prolong operative time (MD = - 2.65, 95% CI - 7.68 to 2.37).

CONCLUSION

RIPC reduced the incidence of POCD in adult patients after general anesthesia and accelerated their discharge.

The risk factors of postoperative cognitive dysfunction in patients undergoing carotid endarterectomy: an updated meta-analysis

OBJECTIVE

The purpose of the current meta-analysis was to determine the incidence and risk factors to provide a scientific basis for prevention and treatment of postoperative cognitive dysfunction (POCD) after carotid endarterectomy (CEA).

METHODS

Relevant articles published before October 2022 were searched from Pubmed/MEDLINE, Cochrane and Embase databases. The outcomes were the incidence and risk factors for POCD. A random-effects model was applied to estimate the overall odds ratios (ORs) and mean differences (MDs) for all risk factors through STATA 14.0 and RevMan 5.4. The quality of eligible studies was evaluated by Newcastle-Ottawa Scale (NOS) as previously described.

RESULTS

A total of 22 articles involving 3459 CEA patients were finally identified. The weighted mean incidence of POCD was 19% (95% confidence intervals (95% CI) 0.16-0.24, P < 0.001). Of the 16 identified risk factors, hyperperfusion (OR: 0.54, 95% CI 0.41-0.71) and degree of internal carotid artery (ICA) stenosis (OR: 5.06, 95% CI 0.86-9.27) were the potential risk factors of POCD, whereas patients taking statins preoperative had a lower risk of POCD (OR: 0.54, 95% CI 0.41-0.71). Subgroup analysis revealed that the risk of POCD at 1 month after CEA was higher in patients with diabetes (OR: 1.70, 95% CI 1.07-2.71).

CONCLUSION

The risk factors of POCD were hyperperfusion and degree of ICA stenosis, while diabetes could significantly increase the incidence of POCD at 1 month after surgery. Additionally, preoperative statin use could be a protective factor for POCD following CEA.

Effects of perioperative intravenous glucocorticoids on perioperative neurocognitive disorders in adults after surgery: A PRISMA-compliant meta-analysis of randomized controlled trials

BACKGROUND

Randomized controlled trials (RCTs) have shown uncertain clinical benefits from perioperative intravenous glucocorticoids for perioperative neurocognitive disorders (PND). Thus, this meta-analysis was performed to evaluate whether perioperative intravenous glucocorticoids can decrease the occurrence of PND among adults undergoing surgery.

METHODS

We searched 4 databases (MEDLINE, Embase, CENTRAL and Web of Science) for RCTs that assessed the incidence of PND in adults (aged ≥ 18 years old) after surgery. Two reviewers independently assessed the studies for eligibility, extracted data, and assessed the risk of bias in each study. We assessed the certainty of evidence using GRADEpro software.

RESULTS

A total of 10 studies (N = 14,967) were eligible. Compared with controls, glucocorticoids were not associated with reducing the risk of postoperative cognitive dysfunction (POCD) (risk ratio [RR]: 0.79 95% confidence interval [CI]: 0.41-1.55, P = .50, I2 = 85%), risk of postoperative delirium (POD) (RR: 0.87 95% CI: 0.74-1.03, P = .10, I2 = 36%), the length of stay in intensive care unit (ICU) (mean difference [MD] -0.21 95% CI: -1.20 to 0.79, P = .68, I2 = 84%), 30-day mortality (RR: 0.92 95% CI: 0.59-1.46, P = .73, I2 = 0%), or postoperative atrial fibrillation (RR: 0.94 95% CI: 0.86-1.01, P = .11, I2 = 25%). However, there was significant difference between glucocorticoids and control group in the length of hospital stay (LOS) (MD: -0.39 95% CI: -0.62 to -0.16, P = .001, I2 = 0%), and postoperative infections (RR: 0.65 95% CI: 0.56-0.76, P < .00001, I2 = 0%).

CONCLUSIONS

Perioperative intravenous glucocorticoids did not reduce the risk of PND in adults after surgery but might be associated with shorter the LOS and lower the incidence of postoperative infections. More, larger, higher-quality RCTs including neurological surgery or hip fracture surgery and different doses of glucocorticoids compared with placebos are needed to explore the intervention effects.

Effect of acupuncture inclusion in the enhanced recovery after surgery protocol on tumor patient gastrointestinal function: a systematic review and meta-analysis of randomized controlled studies

Introduction

Acupuncture has been shown to be effective in restoring gastrointestinal function in tumor patients receiving the enhanced recovery after surgery (ERAS) protocol. The present systematic review and meta-analysis aimed to evaluate the rationality and efficacy of integrating acupuncture in the ERAS strategy to recuperate gastrointestinal function.

Methods

We searched eleven databases for relevant randomized clinical trials (RCTs) of acupuncture for the treatment of gastrointestinal dysfunction in tumor patients treated with the ERAS protocol. The quality of each article was assessed using the Cochrane Collaboration risk of bias criteria and the modified Jadad Scale. As individual symptoms, the primary outcomes were time to postoperative oral food intake, time to first flatus, time to first distension and peristaltic sound recovery time (PSRT). Pain control, adverse events, and acupoint names reported in the included studies were also investigated.

Results

Of the 211 reviewed abstracts, 9 studies (702 patients) met eligibility criteria and were included in the present systematic review and meta‑analysis. Compared to control groups, acupuncture groups showed a significant reduction in time to postoperative oral food intake [standardized mean difference (SMD) = -0.77, 95% confidence interval (CI) -1.18 to -0.35], time to first flatus (SMD=-0.81, 95% CI -1.13 to -0.48), time to first defecation (SMD=-0.91, 95% CI -1.41 to -0.41, PSRT (SMD=-0.92, 95% CI -1.93 to 0.08), and pain intensity (SMD=-0.60, 95% CI -0.83 to -0.37).The Zusanli (ST36) and Shangjuxu (ST37) acupoints were used in eight of the nine included studies. Adverse events related to acupuncture were observed in two studies, and only one case of bruising was reported.

Discussion

The present systematic review and meta‑analysis suggested that acupuncture significantly improves recovery of gastrointestinal function and pain control in tumor patients receiving the ERAS protocol compared to the control group. Moreover, ST36 and ST37 were the most frequently used acupoints. Although the safety of acupuncture was poorly described in the included studies, the available data suggested that acupuncture is a safe treatment with only mild side effects. These findings provide evidence-based recommendations for the inclusion of acupuncture in the ERAS protocol for tumor patients.

Systematic review registration

https://www.crd.york.ac.uk/prospero/ PROSPERO, identifier CRD42023430211.

Appropriate time to radical surgery for colorectal cancer patients complicated with newly onset cerebral infarction: a propensity score matching analysis

The purpose of our study was to compare the short-term outcomes of early (within 3 months after stroke) and nonearly (more than 3 months after stroke) radical colorectal cancer surgery to find an appropriate time to surgery for these colorectal cancer patients complicated with new-onset cerebral infarction. A retrospective analysis of patients with stroke who underwent curative colorectal cancer surgery between January 2010 and December 2020 was conducted. Propensity score matching (PSM) analysis was performed to overcome patient selection bias between the two groups. A total of 395 patients were reviewed. After PSM, 40 patients in the early group and 40 patients in the nonearly group were compared. The median time to surgery was 4 weeks in the early group. The overall incidence of postoperative complications between the groups was not significantly different (p = 0.745). The early group was associated with less intraoperative blood loss (50 vs. 100, p = 0.029 ml), with no difference in 30-day morbidity and mortality. Additionally, multivariate logistic regression analysis showed that previous abdominal surgery (p = 0.049) was an independent risk factor for postoperative complications after matching. Before matching, multivariate logistic analysis showed that ESRS (p = 0.028) and MRS (p = 0.039) were independent risk factors. Radical surgery after 4 weeks of cerebral infarction may be feasible for colorectal cancer patients with new onset stroke, as it appear not to increase the perioperative complications of Clavien-Dindo grade II or higher, while strengthening the preoperative evaluation and perioperative monitoring.

Effects of Remote Ischemic Preconditioning on Postoperative Cognitive Dysfunction in Elderly Patients with Laparoscopic Cholecystectomy

Purpose

We hypothesized that remote ischemic preconditioning (RIPC) could improve postoperative cognitive dysfunction (POCD) in elderly patients following laparoscopic cholecystectomy (LC).

Patients and Methods

Eighty-eight patients were randomly assigned to either the control or the RIPC group. The RIPC was applied on the right upper limb using a blood pressure cuff inflating 200 mmHg, consisting of 3 cycles of 5 min ischemia and 5 min reperfusion. Serum concentrations of Neuron-specific Enolase (NSE) and Brain-Derived Neurotrophic Factor (BDNF) were collected at one-day preoperative (T0), at the end of the operation (T4) and one-day postoperative (T5). Z score was tested at T0 and 3 days after the operation (T6). POCD was determined if there were two Z scores ≥1.96 at the same time or an average Z score ≥1.96.

Results

There was no significant difference in the Z score of each test between the two groups at T0 (P > 0.05). Notably, the duration of Stroop test C was significantly shorter in the RIPC group than that in the Control group at T6 (P = 0.01). POCD occurred in 1/44 (2.3%) patients in the RIPC group and 8/44 (18.2%) patients in the control group at T6 (P=0.035). In addition, serum NSE concentration was significantly decreased, but serum BDNF concentration was increased compared with the control group at T4 and T5 (P<0.001).

Conclusion

RIPC could reduce the incidence of POCD in elderly patients after laparoscopic cholecystectomy.

Longitudinal Profiling of Plasma Cytokines and Its Association With Postoperative Delirium in Elderly Patients Undergoing Major Lower Limb Surgery: A Prospective Observational Study

BACKGROUND

Surgery is accompanied by a systemic inflammatory response that may presage delirium in susceptible individuals. Little is known about the trajectory of plasma proinflammatory cytokines and their potential associations with postoperative delirium (POD). The current study longitudinally assessed both pro and anti-inflammatory plasma cytokine response and development of POD in older surgical patients to investigate associations with individual and/or clusters of cytokines that may indicate pathogenic mechanisms.

METHODS

A prospective longitudinal study sought to enroll patients >60 years old who were scheduled for major lower limb surgery under general anesthesia. Blood was obtained preoperatively and postoperatively from day 1 through postoperative day 4 for measurement of plasma interleukin-1β (IL-1β), IL-2, IL-4, IL-6, soluble IL-6 receptor (sIL-6R), IL-10, and tumor necrosis factor-α (TNF-α). Participants were assessed for POD twice daily for 4 days using the confusion assessment method. Trajectory of postoperative changes in plasma cytokines was determined by a group-based trajectory modeling analysis that was informed by distinct cytokines identified by time-dependent Cox regression model.

RESULTS

One hundred eighty-eight patients were assessed for eligibility of whom 129 underwent major surgery and 126 had complete datasets for final analysis. POD was diagnosed in 31 of 126 patients (24.6%). Time-dependent Cox regression model identified that higher IL-6 and sIL-6R levels were associated with higher risk of developing POD. A two-cluster model (stable lower and fluctuating higher levels) was considered to be the most statistically appropriate model for IL-6 and sIL-6R trajectory. More participants with fluctuating higher IL-6 were delirious (73.3% vs 18.0%, P = .001) as were those with fluctuating higher sIL-6R (81.3% vs 16.4%, P = .001).

CONCLUSIONS

As higher IL-6 and sIL-6R levels were significantly associated with higher risk of POD and the combination is required for IL-6 trans-signaling, it is possible that activation of this pathway may be associated with POD. Furthermore, it will be important to determine whether high levels of the combination of IL-6 and sIL-6R can be an early biomarker for the subsequent development of POD.

SOLUBLE GUANYLYL CYCLASE ACTIVATION RESCUES HYPEROXIA-INDUCED DYSFUNCTION OF VASCULAR RELAXATION

ABSTRACT

Introduction: Perioperative alterations in perfusion lead to ischemia and reperfusion injury, and supplemental oxygen is administered during surgery to limit hypoxic injury but can lead to hyperoxia. We hypothesized that hyperoxia impairs endothelium-dependent and endothelium-independent vasodilation but not the vasodilatory response to heme-independent soluble guanylyl cyclase activation. Methods: We measured the effect of oxygen on vascular reactivity in mouse aortas. Mice were ventilated with 21% (normoxia), 60% (moderate hyperoxia), or 100% (severe hyperoxia) oxygen during 30 minutes of renal ischemia and 30 minutes of reperfusion. After sacrifice, the thoracic aorta was isolated, and segments mounted on a wire myograph. We measured endothelium-dependent and endothelium-independent vasodilation with escalating concentrations of acetylcholine (ACh) and sodium nitroprusside (SNP), respectively, and we measured the response to heme-independent soluble guanylyl cyclase activation with cinaciguat. Vasodilator responses to each agonist were quantified as the maximal theoretical response ( Emax ) and the effective concentration to elicit 50% relaxation (EC 50 ) using a sigmoid model and nonlinear mixed-effects regression. Aortic superoxide was measured with dihydroethidium probe and high-performance liquid chromatography quantification of the specific superoxide product 2-hydroxyethidium. Results: Hyperoxia impaired endothelium-dependent (ACh) and endothelium-independent (SNP) vasodilation compared with normoxia and had no effect on cinaciguat-induced vasodilation. The median ACh Emax was 76.4% (95% confidence interval = 69.6 to 83.3) in the normoxia group, 53.5% (46.7 to 60.3) in the moderate hyperoxia group, and 53.1% (46.3 to 60.0) in the severe hyperoxia group ( P < 0.001, effect across groups), while the ACh EC 50 was not different among groups. The SNP Emax was 133.1% (122.9 to 143.3) in normoxia, 128.3% (118.1 to 138.6) in moderate hyperoxia, and 114.8% (104.6 to 125.0) in severe hyperoxia ( P < 0.001, effect across groups), and the SNP EC 50 was 0.38 log M greater in moderate hyperoxia than in normoxia (95% confidence interval = 0.18 to 0.58, P < 0.001). Cinaciguat Emax and EC 50 were not different among oxygen treatment groups (median range Emax = 78.0% to 79.4% and EC 50 = -18.0 to -18.2 log M across oxygen groups). Aorta 2-hydroxyethidium was 1419 pmol/mg of protein (25th-75th percentile = 1178-1513) in normoxia, 1993 (1831-2473) in moderate hyperoxia, and 2078 (1936-2922) in severe hyperoxia ( P = 0.008, effect across groups). Conclusions: Hyperoxia, compared with normoxia, impaired endothelium-dependent and endothelium-independent vasodilation but not the response to heme-independent soluble guanylyl cyclase activation, and hyperoxia increased vascular superoxide production. Results from this study could have important implications for patients receiving high concentrations of oxygen and at risk for ischemia reperfusion-mediated organ injury.

Perioperative Acupuncture Optimizes Surgical Outcomes: Theory, Clinical Practice and Future Perspectives

A growing body of evidence supports the use of perioperative acupuncture as part of an enhanced postsurgical recovery protocol. Data from both clinical trials and animal studies has shown that the integration of acupuncture into perioperative patient care leads to a reduction of perioperative complications such as preoperative anxiety, intraoperative hemodynamic instability, postoperative pain, postoperative cognitive dysfunction, and postoperative nausea and vomiting in surgical patients. Despite these favorable outcomes, perioperative acupuncture has yet to be widely adopted in current anesthesia practice. This review summarized data from clinical perioperative acupuncture studies and cites recent discoveries regarding the anatomical location and characteristics of acupoint(s), acupuncture stimulation techniques, and treatment practice protocols, as well as identified the areas of deficiency in perioperative acupuncture applications. To facilitate acupuncture integration in perioperative care practice, the authors propose to establish a perioperative acupuncture registry which can be used for data mining as well as a resource for studying the underlying mechanisms of acupuncture. Through this acupuncture registry, clinical guidelines and research protocols can be established, additional large/multi-center clinical and pragmatic trials can be easily performed to determine if the integration and expansion of perioperative acupuncture practice is cost-effective.

Influences of remote ischemic preconditioning on postoperative delirium and cognitive dysfunction in adults after cardiac surgery: a meta-analysis of randomized controlled trials

Background

Remote ischemic preconditioning (RIPC) has been suggested to confer neuroprotective effect. However, influences of RIPC on postoperative delirium (POD) and cognitive dysfunction (POCD) in adults after cardiac surgery are less known. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the effects of RIPC on POD and POCD.

Methods

Relevant studies were obtained by search of PubMed, Embase, and Cochrane’s Library databases. A random-effect model was used to pool the results.

Results

Ten RCTs including 2303 adults who received cardiac surgery were included. Pooled results showed that RIPC did not significantly affect the incidence of POD (six RCTs, odds ratio [OR] 1.07, 95% confidence interval [CI] 0.81 to 1.40, P = 0.65) with no significant heterogeneity (I² = 0%). In addition, combined results showed that RIPC did not significantly reduce the incidence of POCD either (six RCTs, OR 0.64, 95% CI 0.37 to 1.11, P = 0.11) with moderate heterogeneity (I² = 44%). Sensitivity analysis by excluding one RCT at a time showed consistent results (P values all > 0.05).

Conclusions

Current evidence from RCTs did not support that RIPC could prevent the incidence of POD or POCD in adults after cardiac surgery. Although these findings may be validated in large-scale RCTs, particularly for the results of POCD, based on these findings, RIPC should not be routinely used as a preventative measure for POD and POCD in adult patients after cardiac surgery.