OBJECTIVE To learn about the factors affecting the quality of the air in operating-rooms and discuss the methods of improving their air quality.METHODS The dynamic and static air bacteriology between laminar air flow operating-room and normal operating-room of a fertiary care level hospital of grade Ⅰ in Changchun were observed.RESULTS The passing rate of samples for air static bacteriology between two types of operating rooms at the begining of selective operations(T0) was without difference.At the begining of emergency operations,there was a disparity.The total number of bacteria in normal operating-room increased with the operating-time,but in the laminar flow operating-room,the total number of bacteria increased in fluctuations during the(T2) time(60 ming since operation begain),and descended dramatically during the(T3) time(90 min since operation).CONCLUSIONS The emergency and operation-time are the main factors affecting the air quality in operating-room and the cleaning air-condition could improve the air quality.

4 h,and for class Ⅰ and class Ⅱ operation.

Objective: To study the characteristics of QT interval dynamicity in patients with heart failure (HF) and provide reference for predicting risk of sudden death in HF patients. Methods: A total of 80 inpatients with chronic HF from our department of cardiology were selected as HF group, and another 50 healthy volunteers were enrolled as healthy control group. All subjects received 24h ambulatory electrocardiography (ECG), surface ECG and echocardiography examination. Left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), QT dispersion (QTd), index for heart rate variability-- standard deviation of normal to normal RR intervals calculated over the 24 h period (SDNN) and slope of QT/RR correlated linear were measured. Results: Compared with healthy control group, there were significant increase in LVESV [(34.0±8.3) ml vs. (90.4±15.4) ml], LVEDV [(86.0±32.2) ml vs. (150.3±30.4) ml], QTd [（35.6±8.5）ms vs.（46.6±10.4）ms], slopes of QTe /RR [(0.136±0.021) vs. (0.175±0.023)] and QTp/RR [(0.130±0.026) vs. (0.158± 0.033)], and significant decrease in LVEF [(60.6±8.4) % vs. (38.5±8.8) %], and SDNN [（140.3±53.3）ms vs.（100.4±40.3）ms] in HF group, P<0.01 all.. Conclusions: Instability of ventricular repolarization in patients with heart failure makes their QT/RR slope significantly higher than that of normal subjects.

Objective:To explore the correlation betWeen deceleration capacity of heart rate (DC)and heart rate var-iability (HRV)in patients With essential hypertension (EH)complicated coronary heart disease (CHD).Methods:DC and HRV Were monitored in 81 patients With EH + CHD (EH + CHD group)and 80 healthy volunteers (healthy control group)respectively.Results:Compared With healthy control group,there Were significant decrease in DC [(11.99±4.93)ms vs.(6.62±1.83)ms],standard deviation of normal to normal RR intervals calculated o-ver the 24 h period [SDNN,(129.94±15.22)ms vs.(63.66±12.13)ms],root-mean square of differences be-tWeen successive normal to normal intervals [rMSSD,(55.52±9.03)ms vs.(28.25±8.81)ms]and adjacent nor-mal RR interval difference > 50ms stroke accounted for a percentage of 24h total RR interval [PNN50,(13.99± 5.63)% vs.(7.29±1.11)%]of HRV in EH + CHD group,P <0.05 all;Pearson correlation analysis indicated that DC Was positively correlatedWith SDNN,rMSSD and PNN50 in EH+CHD patients (r =0.571,0.662,0.763, P <0.05 all).Conclusion:There is positive correlation betWeen deceleration capacity of heart rate and heart rate variability in patients With hypertension complicated coronary heart disease,Which can be jointly used as evidence for diagnosis and treatment.