OBJECTIVETo evaluate the efficacy and safety of intravenous esmolol, amiodarone and diltiazem for controlling rapid ventricular rate in patients with atrial fibrillation (AF) during anesthesia period.

METHODSNinety AF patients with rapid atrial ventricular rate (≥ 120 beats/min) in anesthesia period were randomly divided into 3 groups (n = 30 each: group I patients were treated with intravenous esmolol (0.5 mg/kg loading dose within 1 minute followed with infusion of 0.05 mg×kg(-1)×min(-1)); group II patients were treated with intravenous amiodarone (loading dose: 3 mg/kg for 10 minutes, followed with intravenous infusion of 1 mg/min); group III patients were treated with intravenous diltiazem (0.25 mg/kg for 5 minutes). The heart rate, blood pressure, rhythm were recorded before treatment, at 5, 10, 15, 30, 60 and 90 min after treatment. The reacting time, side effects including hypotension, bradycardia, nausea, vomiting, dizziness, etc, were analyzed.

RESULTSThe mean reacting time was significantly shorter in group I (4.3 ± 2.1) min than in group II (19.2 ± 8.5) min and in group III (8.5 ± 3.4) min (P < 0.05). The mean reacting time in group III was significantly shorter than in group II (P < 0.05). The total effective rate were similar among the groups (86.7%, 90.0% and 83.3% with a mean decrease in heart ventricular rate by 42.4%, 42% and 41.9% of the baseline level in group I, group II and group III, respectively). The incidence of total side effect was significantly lower in group II (10%) than in group I (16.7%) and group III (20%, P < 0.05).

CONCLUSIONSIntravenous esmolol, amiodarone and diltiazem are all equally effective and safe on controlling rapid ventricular rate in patients with atrial fibrillation during the anesthesia period. Esmolol use is associated with the shortest mean reacting time and amiodarone use is associated with the lowest total side effect rate in this patient cohort.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Amiodarone ; therapeutic use ; Anesthesia ; Atrial Fibrillation ; drug therapy ; physiopathology ; Child ; Diltiazem ; therapeutic use ; Female ; Heart Rate ; Humans ; Male ; Middle Aged ; Propanolamines ; therapeutic use ; Treatment Outcome ; Young Adult

Objective To design a new type of external fixator for bone fracture and verify its rationality and feasibility. Methods The frame and screw of stainless steel achieved fracture fixation in vitro with a threaded locking structure.At the same time the increasing thickness of body frame, the inclined nail holes and the raised bottoms were designed to greatly enhance the strength and overall stability of body frame.FEM (finite element method),measuring the relative displacement and stress distribution after axial load,was used to verify the rationality of the design.An animal experiment with sheep was used to verify the feasibility of fracture treatment. Results Simulated result of FEM indicated that the biggest relative displacement between the separated bones was 0.04 mm,which was much less than the minimum value 1 mm required for fracture healing.The maximum stresses applied on the frame of the fixator,fixator screw,and bone were 35,26,and 6 MPa, respectively, which was much less than the allowable stress. In the animal experiment, fracture site was fixed firmly after operation and was well cured 3 months later.Conclusion The design of this new device is feasible and it can be used as a new method of fracture treatment.

The advantages and disadvantages of different treatment methods of traditional tibial fracture were summarized. The research progress on the treatment of tibial fracture with internal fixation plates as external fixators was introduced from two aspects of biomechanics and clinical application. It was proved that internal fixation plates as external fixators could reduce the structural stability, but this technique was still controversial to meet the mechanical requirements of fracture healing on biomechanics.Internal fixation plates as external fixators,it had the advantages of minimal invasion,high healing rate, less complications and favorable activities. It's pointed out clinical trials on its feasibility and availability as well as simulating body mechanics environment should be carried out to provide basis for relevant biomechanics researches.

Humans ; Female ; Prevalence ; Breast Neoplasms ; Cancer Survivors ; Non-alcoholic Fatty Liver Disease ; Liver

Background: The long-term predicted value of microvolt T-wave alternans (MTWA) for ventricular tachyarrhythmia in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) remains unclear. Our study explored the characteristics of MTWA and its prognostic value when combined with an electrophysiologic study (EPS) in patients with ARVC. Methods: All patients underwent non-invasive MTWA examination with modified moving average (MMA) analysis and an EPS. A positive event was defined as the first occurrence of sudden cardiac death, documented sustained ventricular tachycardia (VT), ventricular fibrillation, or the administration of appropriate implantable cardioverter defibrillator therapy including shock or antitachycardia pacing. Results: Thirty-five patients with ARVC (age 38.6 ± 11.0 years; 28 males) with preserved left ventricular (LV) function were recruited. The maximal TWA value (MaxValt) was 17.0 (11.0–27.0) μV. Sustained VT was induced in 22 patients by the EPS. During a median follow-up of 99.9 ± 7.7 months, 15 patients had positive clinical events. When inducible VT was combined with the MaxValt, the area under the curve improved from 0.739 to 0.797. The receiver operating characteristic curve showed that a MaxValt of 23.5 μV was the optimal cutoff value to identify positive events. The multivariate Cox regression model for survival showed that MTWA (MaxValt, hazard ratio [HR], 1.06; 95% confidence interval [CI], 1.01–1.11; P = 0.01) and inducible VT (HR, 5.98; 95% CI, 1.33–26.8; P = 0.01) independently predicted positive events in patients with ARVC. Conclusions MTWA assessment with MMA analysis complemented by an EPS might provide improved prognostic ability in patients with ARVC with preserved LV function during long-term follow-up.