Effect of Different Administration Routes of Dexmedetomidine on Postoperative Delirium in Elderly Patients Undergoing Elective Spinal Surgery: A Prospective Randomized Double-Blinded Controlled Trial.

BACKGROUND: Intravenous dexmedetomidine has been reported to decrease the occurrence of postoperative delirium (POD) in elderly patients. Nevertheless, some previous studies have indicated that intratracheal dexmedetomidine and intranasal dexmedetomidine are also effective and convenient. The current study aimed to compare the effect of different administration routes of dexmedetomidine on POD in elderly patients. METHODS: We randomly allocated 150 patients (aged 60 years or more) scheduled for spinal surgery to receive intravenous dexmedetomidine (0.6 µg/kg), intranasal dexmedetomidine (1 µg/kg) before anesthesia induction, or intratracheal dexmedetomidine (0.6 µg/kg) after anesthesia induction. The primary outcome was the frequency of delirium during the first 3 postoperative days. The secondary outcomes were the incidence of postoperative sore throat (POST) and sleep quality. Adverse events were recorded, and routine treatment was performed. RESULTS: Compared with the intranasal group, the intravenous group had a significantly lower occurrence of POD within 3 days (3 of 49 [6.1%] vs 14 of 50 [28.0%]; odds ratio [OR], 0.17; 95% confidence intervals [CIs], 0.05-0.63; P < .017). Meanwhile, patients in the intratracheal group had a lower incidence of POD than those in the intranasal group (5 of 49 [10.2%] vs 14 of 50 [28.0%]; OR, 0.29; 95% CI, 0.10-0.89; P < .017). Whereas, there was no difference between the intratracheal and intravenous groups (5 of 49 [10.2%] vs 3 of 49 [6.1%]; OR, 1.74; 95% CI, 0.40-7.73; P > .017). The rate of POST was lower in the intratracheal group than that in the other 2 groups at 2 hours after surgery (7 of 49 [14.3%] vs 12 of 49 [24.5%] vs 18 of 50 [36.0%], P < .017, respectively). Intravenous dexmedetomidine had the lowest Pittsburgh Sleep Quality Index score on the second morning after surgery (median [interquartile range {IQR}]: 4 [3-5] vs 6 [4-7] vs 6 [4-7], P < .017, respectively). Compared with the intranasal group, the intravenous group had a higher rate of bradycardia and a lower incidence of postoperative nausea and vomiting ( P < .017). The intranasal group was associated with the highest incidence of hypertension ( P < .017). CONCLUSIONS: For patients aged ≥60 years undergoing spinal surgery, compared with the intranasal route of dexmedetomidine, intravenous and intratracheal dexmedetomidine reduced the incidence of early POD. Meanwhile, intravenous dexmedetomidine was associated with better sleep quality after surgery, and intratracheal dexmedetomidine resulted in a lower incidence of POST. Adverse events were mild in all 3 administration routes of dexmedetomidine.

[Finite element analysis of the stability of Mason type â ¢ radial head fracture fixed with three cross-bridge headless compression screw and locking plate].

OBJECTIVE: To compare the biomechanical stability of three cross-bridge headless compression screws and locking plates in the fixation of Mason type Ⅲ radial head fractures by finite element method. METHODS: Using reverse modeling technology, the radial CT data and internal fixation data of a healthy 25-year-old male were imported into the relevant software. Three-dimensional finite element model of 3 cross-bridge headless compression screws and locking plates for MasonⅢ radial head fractures were established, and the radial head was loaded with 100 N axial loading. The maximum displacement, maximum Von Mises stress and stress distribution of the two groups were compared. RESULTS: The maximum displacements of the three cross-bridge screws group and locking plate group were 0.069 mm and 0.087 mm respectively, and the Von Mises stress peaks were 18.59 MPa and 31.85 MPa respectively. The stress distribution of the three screws group was more uniform. CONCLUSION: Both internal fixation methods can provide good fixation effect. CoMPared with the locking plate fixation method, the 3 cross-bridge headless compression screws fixation is more stable and the stress distribution is more uniform.

[Activation of nuclear factor kappaB signaling pathway in human osteoblasts responses to Staphylococcus aureus in vitro].

OBJECTIVE: To investigate whether S. aureus could activate NF-κB signaling pathway in human osteoblasts. METHODS: Immunoblot and electrophoretic mobility shift assay were used to detect the degradation of I-κBα and activation of NF-κB in human osteoblasts following infection with S.aureus, respectively, and there were investigated the activated state of NF-κB signaling pathway in human osteoblasts. In addition, enzyme-linked immunosorbent assay was used to measure the secretion of IL-6 in culture supernatants, which was represented as one of important cytokines in osteomyelitis, and an inhibitor of NF-κB, SN50, which was added to human osteoblasts culture prior to 1 hour at 50 µmol/L before the infection of S.aureus, was used to determine whether S.aureus-activated NF-κB signaling pathway regulates IL-6 secretion of human osteoblasts. RESULTS: S.aureus could induce the degradation of I-κBα (I-κBα(15 min)/I-κBα(0 min) = 0.409 ± 0.245 and I-κBα(30 min)/I-κBα(0 min) = 0.061 ± 0.010) and activation of NF-κB in human osteoblasts in a time and dose-dependent manner following infection. In addition, the secretion of IL-6 in the supernatants of human osteoblasts ((2.17 ± 0.11) µg/L) was suppressed by 50 µmol/L SN50 compared to without the addition of SN50 ((3.58 ± 0.31) µg/L) (F = 174.25, P < 0.05). CONCLUSIONS: S.aureus could activate NF-κB signaling pathway in human osteoblasts, which could regulate cytokines secretions of human osteoblasts.

[Curative effect comparison for fixation of fibula or not for the treatment of middle and lower 1/3 fractures of tibia and fibula with intramedullary nail].

OBJECTIVE: To analyze and compare the effect of fibular plate fixation on the treatment of tibial and fibular fractures. METHODS: From July 2016 to September 2018, 65 cases of middle and lower 1/3 fractures of tibia and fibula were retrospectively analyzed, including 46 males and 19 females, aged 22 to 61 years old. There were 37 cases in fibular fixation group (27 males and 10 females) , 28 cases in fibular non fixation group (19 males and 9 females) . By comparing the operation time, intraoperative bleeding, fracture healing time, ankle rotation and valgus angle, postoperative complications, last follow-up ankle mobility and Baird Jackson score, the operation effect was evaluated. RESULTS: All patients were followed up for 12 to 16 months with an average of (13.67±1.23) months. There were 3 cases of infection of the fibular incision, all of which healed in the first stage without incision dehiscence, and 4 cases of delayed union without nonunion. In the fibula fixation group, the external rotation of ankle joint increased (7.16±1.36) ° and the valgus angle increased (3.35±1.16) °; while in the non fixation group, the external rotation increased (10.25±1.58) ° and the valgus angle increased (6.46±1.23) ° with statistical significance (P<0.05) . There was no significant difference in ankle joint activity, fracture healing time and complication rate between two groups (P>0.05) ; there was significant difference in operation time, intraoperative hemorrhage and Baird Jackson score at the latest follow-up (P<0.05) . CONCLUSION: The fibular plate fixation can prevent the ankle joint from malrotation and valgus deformity, and can obtain better surgical effect and functional prognosis.

The effect of Staphylococcus aureus on apoptosis of cultured human osteoblasts.

OBJECTIVE: To investigate the effect of Staphylococcus aureus (S. aureus) on cultured human osteoblast apoptosis and the corresponding mode of action. METHODS: Transmission electron microscopy (TEM), assessment of DNA laddering, and flow cytometry assays were used to investigate human osteoblast apoptosis following infection with S. aureus. RESULTS: TEM examination and DNA laddering assessment indicated that S. aureus can induce cultured human osteoblast apoptosis. Flow cytometry assays showed that human osteoblast apoptosis occurs in a dose-dependent manner following infection with S. aureus. In addition, compared with under co-culture conditions, inhibition of invasion by S. aureus resulted in a 64.62% reduction in the percentage of early apoptotic cells (P < 0.01); 7.09% ± 1.21% of human osteoblasts under indirect co-culture with S. aureus at a multiplicity of infection of 250 showed an early apoptotic profile compared with uninfected controls(P < 0.01). CONCLUSIONS: S. aureus induces cultured human osteoblast apoptosis in a dose-dependent manner. Intracellular S. aureus is mainly responsible for cultured human osteoblast apoptosis following infection; secreted soluble factor(s) of S. aureus playing a minor role in this process.