[Pharmacokinetics Study of Phentolamine Mesylate Injection in Healthy Volunteers].

OBJECTIVE: To study the pharmacokinetic profile of phentolamine mesylate injection in healthy Chinese volunteers. METHODS: A total of 16 healthy volunteers were randomly divided into two groups, each receiving anterior teeth submucosal infiltration anesthesia and inferior alveolar nerve block anesthesia, respectively. The participants were injected with 0.9 mL, 1.8 mL, and 3.6 mL of 2% lidocaine HCl with 1∶100 000 epinephrine over three periods sequentially, followed by corresponding sequential injection of 0.2 mg, 0.4 mg, 0.8 mg of phentolamine mesylate at the same sites 30 min later.Blood samples were drawn from 5 min before injection to 15 h post the injection of phentolamine mesylate (16 time points). Adverse events were closely observed all the time. Plasma phentolamine mesylate was detected using UPLC-MS/MS with isotope as internal standard. WinNolin 6.1 software was used to calculate the pharmacokinetic parameters. RESULTS: Time to peak concerntration (Tmax) ranged from 12 to 13 min. Half-time of elimination (t1/2) ranged from 3.84 to 4.07 h, with a clearance (CL) of 190 L/h. Peak concentration (Cmax), area under concentration-time curves from 0 to t hour and from 0 to infinite time (AUC0-t and AUC0-∞) increased proportionally in the dose range of 0.2 mg to 0.8 mg. The results of confidence interval analysis showed nearly linear dynamic characteristics for the injection of phentolamine mesylate. All participants experienced mild adverse events, including pain at the injection point, dizziness, and palpitations. These adverse events disappeared without treatments. CONCLUSIONS: Phentolamine mesylate injection is effective for reversing oral local anesthetic effects.

Is it Beneficial to Reuse the Balloon in Percutaneous Kyphoplasty for the Treatment of Non-Neoplastic Vertebral Compression Fractures?

BACKGROUND Percutaneous kyphoplasty (PKP) has been widely used to treat vertebral compression fractures (VCFs). Bilateral percutaneous punctures are always performed to access the fractured vertebrae. However, the procedure has expensive clinical costs, especially the cost for the device, which creates a heavy financial burden for patients. MATERIAL AND METHODS Data from 49 patients who have single-level non-neoplastic vertebral compression fracture (VCF) were collected for 12 months after treated by PKP, including 21 cases that used bilateral puncture with single balloon (S group) and 28 cases that used bilateral puncture with double balloon (D group). We assessed the clinical (visual analogue scale, VAS) and radiological (vertebral height and kyphotic angle, KA) outcomes. Cost data (gross medical cost, cost for the device and cost for drugs) were obtained from the medical bill of each patient. RESULTS Baseline patient variables were similar between the two groups except the compensation (S group