Comparison of General vs. Intraspinal Anesthesia in Lower Limb Fracture Surgery: A Prospective Study.

Objective: This study was carried out to evaluate the effectiveness of general versus intraspinal anesthesia in lower limb fracture surgery. Methods: Between January 2018 and August 2022, the researchers' hospital recruited and randomized 433 patients who underwent surgery for lower limb fractures. The study population was divided into 2 groups. Group A (n=220) received general anesthesia during surgery; group B (n=213) received intraspinal anesthesia. Factors were recorded and analyzed, including anesthesia duration, operative time, length of hospital stay, and laboratory indices such as hemoglobin (Hb), serum glutamate pyruvate transaminase (SGPT), blood urea nitrogen (BUN), creatinine (Cr). All adverse events were monitored as well. Results: There were no significant differences in anesthesia duration, surgery time, and length of hospital stay between the two patient groups (P > .05). After receiving different anesthesia approaches, both groups had similar laboratory results (P > .05). The absence of significant differences in adverse events between the two groups indicates that both methods of anesthesia have comparable surgical safety (P > .05). Conclusion: Both general anesthesia and intraspinal anesthesia provided effective anesthetic effects for lower limb fracture surgery with a similar safety profile. Patients also showed similar laboratory indices and experienced comparable anesthesia duration, operative time, and length of hospital stay.

Effect of intraoperative low vs. conventional tidal volume on the incidence of postoperative acute kidney injury after noncardiac surgery: a two-center randomized clinical trial.

BACKGROUND: In adults undergoing noncardiac surgery, the correlation between intraoperative tidal volume and postoperative acute kidney injury (AKI) is unclear. This study aimed to investigate the effects of low tidal volume ventilation on the incidence of postoperative AKI compared with conventional tidal volume in adults undergoing noncardiac surgery. METHODS: This was a two-center prospective randomized controlled trial on adult patients who underwent noncardiac surgery and had a mechanical ventilation of >60 min. Patients were randomized to receive either a tidal volume of 6 mL/kg pre-predicted body weight (PBW, low tidal volume) or a tidal volume of 10 mL/kg pre-predicted body weight (conventional tidal volume). The primary outcome was the incidence of AKI after non-cardiac surgery. Appropriate statistical methods were used for this study. RESULTS: Among the 1982 randomized patients, 943 with low tidal volume and 958 with conventional tidal volume were evaluable for the primary outcome. Postoperative AKI occurred in 12 patients (1.3%) in the low tidal volume group and 11 patients (1.1%) in the conventional tidal volume group, with an odds ratio of 0.889 (95%CI, 0.391-2.03) and a relative risk of 0.999 ([95%CI, 0.989-1.01]; P=0.804). Postoperative serum creatinine levels increased in 284 (30.0%) patients with low tidal volume compared to 316 (32.0%) patients with conventional tidal volume (P=0.251). No difference in postoperative serum creatinine levels was found between the two groups (57.5 [49.0-68.2] µmol/L vs. 58.8[50.4-69.5] µmol/L, P=0.056). CONCLUSIONS: Among adults undergoing noncardiac surgery, low tidal volume mechanical ventilation did not significantly reduce the incidence of postoperative AKI compared with conventional tidal volume.

Ultrasound-Guided Modified Thoracolumbar Fascial Plane Block in Tianji Robot-Assisted Lumbar Internal Fixation: A Prospective, Randomized, and Non-Inferiority Study.

Purpose: Ultrasound-guided modified thoracolumbar fascial plane block (MTLIP) has been reported effective for postoperative pain control following lumbar surgery. Although trauma of the Tianji robot-assisted lumbar internal fixation is reduced, the degree of pain cannot be ignored.MTLIP may improve operation efficiency and reduce puncture complications.This study aimed to explore whether MTLIP is not inferior to thoracolumbar fascial plane block (TLIP) in the treatment of lumbar internal fixation. Methods: This prospective double-blinded, non-inferiority randomized trial enrolled patients underwent Tianji robot-assisted lumbar internal fixation between April and August 2022 to either MTLIP or TLIP. The primary outcome was an effective dermatomal block area after 30 min. Secondary outcomes included the numeric rating scale (NRS) scores, nerve block operation time, puncture times, image clarity, patient satisfaction, intraoperative opioid consumption, complications/adverse reactions, and Oswestry Disability Index (ODI). Results: Sixty participants were randomized to MTLIP (n=30) and TLIP (n=30). The effective dermatomal block area 30 min after block was non-inferior in the MTLIP group (283.6 ± 62.6 cm2) compared with the TLIP group (261.4±53.2 cm2) (P=0.145; estimated mean difference: -22.17, 95% CI: -52.19, 7.85; smaller than the non-inferiority margin of 39.5). Compared with TLIP, MTLIP showed shorter operation time, smaller puncture times, and better target definition and satisfaction scores (all P<0.001). Sufentanil amount, remifentanil amount, PCIA sufentanil dosage, parecoxib amount, NRS scores (increased with time in the two groups but without inter-group differences), and complications were not significantly different between the two groups (all P>0.05). Conclusion: This non-inferiority trial supports the hypothesis that MTLIP yields a non-inferior effective dermatomal block area compared with TLIP for Tianji robot-assisted lumbar internal fixation. Clinical Trials Registration: Chinese Clinical Trial Registry (ChiCTR2200058687);.

Ketamine administration ameliorates anesthesia and surgery-induced cognitive dysfunction via activation of TRPV4 channel opening.

Perioperative neurocognitive disorder (PND) is a common complication associated with anesthesia and surgery in the elderly. The dysfunction of transient receptor potential vanilloid 4 (TRPV4) has been associated with a number of diseases, including Alzheimer's disease. Given that ketamine can reportedly improve PNDs, the present study sought to determine whether ketamine-induced PND alleviation was mediated by activation of TRPV4 channel opening. A total of 120, 20-month-old male C57BL/6 mice were randomly divided into five groups: Vehicle, PND (tibial fracture surgery), PND + ketamine (Ket), PND + Ket + HC-067047 (HC), and PND + HC groups. Ketamine (0.5 mg/kg) was administered intraperitoneally once a day for 3 days after surgery and HC-067047 (1 µmol/2 µl), an antagonist of TRPV4, was administered via the left lateral ventricle 30 min before ketamine treatment. Superoxide dismutase (SOD), malondialdehyde (MDA), lipid peroxidation (LPO), IL-1ß, IL-6, adenosine monophosphate-activated protein kinase (AMPK), NF-κB, TNF-α and IFN-ß levels were determined 3 days after surgery. At 28 days after surgery, fear conditioning and novel object recognition were assessed, and Aß1-42 levels were measured and ionized calcium binding adaptor molecule 1 (Iba1) staining was conducted on day 31 after surgery. The results revealed that ketamine administration upregulated total SOD activity, downregulated MDA and LPO content, mitigated phosphorylated (p)-NF-κB, TNF-α mRNA and IFN-ß mRNA expression in the hippocampus, and promoted p-AMPK 3 days after surgery. Furthermore, it was found that ketamine increased both context- and tone-dependent fear conditioning, and the time spent exploring a novel object, and reduced Aß peptide levels and microglial activation 30 days after surgery. Notably, these changes could be reversed by HC-067047 to a certain extent. In conclusion, ketamine improved PND in aged mice after tibial fracture surgery and the potential mechanism may involve activation of the TRPV4/AMPK/NF-κB signaling pathway.

Role of mTOR-Regulated Autophagy in Synaptic Plasticity Related Proteins Downregulation and the Reference Memory Deficits Induced by Anesthesia/Surgery in Aged Mice.

Postoperative cognitive dysfunction increases mortality and morbidity in perioperative patients and has become a major concern for patients and caregivers. Previous studies demonstrated that synaptic plasticity is closely related to cognitive function, anesthesia and surgery inhibit synaptic function. In central nervous system, autophagy is vital to synaptic plasticity, homeostasis of synapticproteins, synapse elimination, spine pruning, proper axon guidance, and when dysregulated, is associated with behavioral and memory functions disorders. The mammalian target of rapamycin (mTOR) negatively regulates the process of autophagy. This study aimed to explore whether rapamycin can ameliorate anesthesia/surgery-induced cognitive deficits by inhibiting mTOR, activating autophagy and rising synaptic plasticity-related proteins in the hippocampus. Aged C57BL/6J mice were used to establish POCD models with exploratory laparotomy under isoflurane anesthesia. The Morris Water Maze (MWM) was used to measure reference memory after anesthesia and surgery. The levels of mTOR phosphorylation (p-mTOR), Beclin-1 and LC3-II were examined on postoperative days 1, 3 and 7 by western blotting. The levels of synaptophysin (SYN) and postsynaptic density protein 95 (PSD-95) in the hippocampus were also examined by western blotting. Here we showed that anesthesia/surgery impaired reference memory and induced the activation of mTOR, decreased the expression of autophagy-related proteins such as Beclin-1 and LC3-II. A corresponding decline in the expression of neuronal/synaptic, plasticity-related proteins such as SYN and PSD-95 was also observed. Pretreating mice with rapamycin inhibited the activation of mTOR and restored autophagy function, also increased the expression of SYN and PSD-95. Furthermore, anesthesia/surgery-induced learning and memory deficits were also reversed by rapamycin pretreatment. In conclusion, anesthesia/surgery induced mTOR hyperactivation and autophagy impairments, and then reduced the levels of SYN and PSD-95 in the hippocampus. An mTOR inhibitor, rapamycin, ameliorated anesthesia/surgery-related cognitive impairments by inhibiting the mTOR activity, inducing activation of autophagy, enhancing SYN and PSD-95 expression.

Grip strength can be used to evaluate postoperative residual neuromuscular block recovery in patients undergoing general anesthesia.

BACKGROUND: Residual postoperative neuromuscular blockade is an important clinical issue. Neuromuscular monitoring is usually used to evaluate neuromuscular recovery in patients undergoing general anesthesia. However, this procedure is inconvenient and not widely adopted. We aimed to examine the correlation between grip strength and train-of-four ratio (TOFr) to examine whether assessing grip strength can be used clinically to monitor residual neuromuscular blockade. METHODS: One hundred twenty patients with ASA I or II scheduled for laparoscopic cholecystectomy under general anesthesia were enrolled in this study. All patients were randomly selected to receive standard anesthesia induction with either 0.6 mg·kg rocuronium or 0.2 mg·kg cisatracurium. Grip strength was tested in all patients using an electronic device before anesthesia and when TOFr values of 0.7, 0.8, and 0.9, and an hour later of TOFr value of 0.25. The time required for a change in TOFr values from 0.25 to 0.75 and 0.9 was evaluated. Spearman rank correlation analysis was performed to determine correlations between grip strength and TOFr. RESULTS: Spearman rank correlation analysis indicated that there was a significant correlation between grip strength and TOFr during patient recovery from general anesthesia (correlation coefficient for grip strength recovery [rs] = 0.886). Subgroup analysis revealed that there were no differences in mean maximum grip value recovery between patients treated with rocuronium and those treated with cisatracurium when TOFr was 0.7, 0.8, and 0.9 or when the TOFr was 0.25 after 60 minutes (all P >.05). Recovery of TOFr from 0.25 to 0.75 and from 0.25 to 0.9 was longer in patients treated with rocuronium than in those treated with cisatracurium (both P <.001). CONCLUSION: There was a strong correlation between grip strength and TOFr during recovery from general anesthesia. Evaluation of grip strength can be used as an additional strategy to evaluate postoperative residual neuromuscular blockade.