Patient dose considerations in computed tomography examinations

Ionizing radiation is extensively used in medicine and its contribution to both diagnosis and therapy is undisputable.However,the use of ionizing radiation also involves a certain risk since it may cause damage to tissues and organs and trigger carcinogenesis.Computed tomography(CT) is currently one of the major contributors to the collective population radiation dose both because it is a relatively high dose examination and an increasing number of people are subjected to CT examinations many times during their lifetime.The evolution of CT scanner technology has greatly increased the clinical applications of CT and its availability throughout the world and made it a routine rather than a specialized examination.With the modern multislice CT scanners,fast volume scanning of the whole human body within less than 1 min is now feasible.Two dimensional images of superb quality can be reconstructed in every possible plane with respect to the patient axis(e.g.axial,sagital and coronal).Furthermore,three-dimensional images of all anatomic structures and organs can be produced with only minimal additional effort(e.g.skeleton,tracheobronchial tree,gastrointestinal system and cardiovascular system).All these applications,which are diagnostically valuable,also involve a significant radiation risk.Therefore,all medical professionals involved with CT,either as referring or examining medical doctors must be aware of the risks involved before they decide to prescribe or perform CT examinations.Ultimately,the final decision concerning justification for a prescribed CT examination lies upon the radiologist.In this paper,we summarize the basic information concerning the detrimental effects of ionizing radiation,as well as the CT dosimetry background.Furthermore,after a brief summary of the evolution of CT scanning,the current CT scanner technology and its special features with respect to patient doses are given in detail.Some numerical data is also given in order to comprehend the magnitude of the potential radiation risk involved in comparison with risk from exposure to natural background radiation levels.

Variation in patient dose due to differences in calibration and dosimetry protocols

For precise and accurate patient dose delivery,the dosimetry system must be calibrated properly according to the recommendations of standard dosimetry protocols such as TG-51 and TRS-398. However, the dosimetry protocol followed by a calibration laboratory is usually different from the protocols that are followed by different clinics, which may result in variations in the patient dose.Our prime objective in this study was to investigate the effect of the two protocols on dosimetry measurements.Dose measurements were performed for a Co-60 teletherapy unit and a high-energy Varian linear accelerator with 6 and 15 MV photon and 6, 9, 12, and 15 MeV electron beams, following the recommendations and procedures of the AAPM TG-51 and IAEA TRS-398 dosimetry protocols. The dosimetry systems used for this study were calibrated in a Co-60 radiation beam at the Secondary Standard Dosimetry Laboratory(SSDL) PINSTECH,Pakistan, following the IAEA TRS-398 protocol. The ratio of the measured absorbed doses to water in clinical setting,D_w(TG-51/TRS-398), was 0.999 and 0.997 for 6 and15 MV photon beams,whereas these ratios were 1.013,1.009, 1.003, and 1.000 for 6, 9, 12, and 15 MeV electron beams, respectively. This difference in the absorbed dosesto-water D_w ratio may be attributed mainly due to beam quality(K_Q) and ion recombination correction factor.

Patient dose from radiographic rejects/repeats in radiology centers of Urmia University of Medical Sciences, Iran

Medical diagnostic X-rays are the largest manmade source of ionizing radiation received by the members of the general public. The aim of this study was to evaluate the radiographic reject/repeat rate and also to determine dose to the patients from radiographic rejects/repeats in radiology centers of Urmia University of Medical Sciences. During a 4 month period the most frequently examinations were chosen in three radiology centers. A form was designed as a reject/repeat analysis form for radiographers to complete each time a film was rejected by radiologists or repeated. The collected data were compiled at the end of each week and entered into a computer for analysis at the end of study. The results of this study showed that highest and lowest repetition rates were for pelvis, 14.01% and upper limb, 4.17%, respectively. The main reasons of repetition of radiographs were due to exposure (54%) and positioning (18%) errors. The average repeat rate in all three hospitals was 7.20%. It was found that human error has important role to repetition of radiographs. It is demonstrated that those patients having repeated radiographs received an average of 3.23 Gy·cm2. Based on the findings of this study it must be remembered that the highest repetition rate was for pelvis. Considering the radiosensitive organs related to pelvis especially in pediatric patients some special considerations must be applied for pelvis examinations.

Study of the External Dose Rate and Retained Body Activity of Patients with Hyperthyroidism Who Are Receiving Ⅰ-131 Therapy

Hyperthyroidism refers to a clinical state that results from inappropriately hight hyroid hormone levels in the tissues;.Ⅰ-131 therapy plays a critical role and provides a remarkable curative effect in targeting thyroid diseases. Thyroid cells can take up isotope I-131, which emits not only beta rays but also

Patient Peak Skin Dose and Dose Area Product from Interventional Cardiology Procedures

Information about the peak skin dose and Dose Area product (DAP) from percutaneous transluminal coronary angioplasty (PTCA) and coronary angiography (CA) was collected from three catheter application rooms. The range of maximum photon energy was 50 - 125 kVp and the fluoroscopy time was 0.6 - 52 seconds. Values of up to 143 Gy·cm2 for DAP and 0.752 mGy for cumulative dose (CD) were found in CA procedures. Otherwise the DAP and CD for PTCA were found to be 143 Gy·cm2 and 2.287 mGy respectively in 3rd Quartile. The relation between the fluoroscopy time and the DAP is also considered. Objectives: The objective of this study is to obtain information about patient peak skin doses (PSD), dose area product (DAP), Fluoroscopy Time (FT) and Cumulative Dose (CD) from PTCA and CA which is the most predominant with respect to high skin doses in addition to other procedures. The aim of this study is also to assess the radiation dose received by patients undergoing interventional radiology procedures, by identifying the procedures that deliver the highest doses. This study is also helpful to establish the reference dose level for adult patients undergoing interventional procedure, and to provide recommendations on how to reduce dose on selected procedures that have been identified to deliver patient dose values near the ICRP (International Commission on Radiological Protection) threshold values.

Gastroduodenal ulcer bleeding in elderly patients on low dose aspirin therapy

AIM To determine the clinical characteristics of elderly patients of hemorrhagic gastroduodenal ulcer on low-dose aspirin(LDA)therapy.METHODS A total of 1105 patients with hemorrhagic gastroduodenal ulcer treated in our hospital between January 2000 and March 2016 were grouped by age and drugs used,and these groups were compared in several factors.These groups were compared in terms of length of hospital stay,presence/absence of hemoglobin(Hb)decrease,presence/absence of blood transfusion,Forrest Ⅰ,percentage of Helicobacter pylori infection,presence/absence of underlying disease,and percentage of severe cases.RESULTS The percentage of blood transfusion(62.6%vs 47.7%,P<0.001),Hb decrease(53.8% vs 40.8%,P<0.001),and the length of hospital stay(23.5 d vs 16.7 d,P<0.001)were significantly greater in those on drug therapy.The percentage of blood transfusion(65.3%vs 47.8%,P<0.001),Hb decrease(54.2%vs 42.1%,P<0.001),and length of hospital stay(23.3 d vs 17.5 d,P<0.001)were significantly greater in the elderly.In comparison with the LDA monotherapy group,the percentage of severe cases was significantly higher in the LDA combination therapy group when elderly patients were concerned(16.1%vs34.0%,P=0.030).Meanwhile,among those on LDA monotherapy,there was no significant difference between elderly and non-elderly(16.1%vs 16.0%,P=0.985).CONCLUSION A combination of LDA with antithrombotic drugs or nonsteroidal anti-inflammatory drugs(NSAIDs)contributes to aggravation.And advanced age is not an aggravating factor when LDA monotherapy is used.

Annual Committed Effective Dose from Various Phytotherapeutic Preparations (due to 238U, 232Th, 222Rn and 220Rn) Estimated for Adult Moroccan Patients

We use a nuclear technique based on the determination of the detection efficiencies of solid state nuclear track detectors CR-39 and LR-115 type II (SSNTDs) for alpha particles emitted from the series of uranium-238 and thorium-232 in a phytotherapeutic sample and the measurement of alpha track densities registered on these detectors to assess alpha activities due to uranium-238;thorium-232;radon and thoron in samples of phytotherapeutic preparations consumed by Moroccan adult patients. For modern preparations, the alpha activities due to 238U, 232Th and 222Rn range from 14.27 mBq/kg to 22.02 mBq/kg, from 6.27 mBq/kg to 9.64 mBq/kg and from 14.27 Bq/kg to 22.02 Bq/kg respectively. For classical preparations, the alpha activities due to 238U, 232Th and 222Rn range from 16.73 mBq/kg to 24 mBq/kg, from 7.34 mBq/kg to 10.82 mBq/kg and from 16.73 Bq/kg to 24.72 Bq/kg respectively. A dosimetric model for ingestion has been highlighted to determine committed equivalent dose to different compartments of human gastrointestinal system due to the ingestion of phytotherapeutic preparations by Moroccan adult patients. The maximum overall effective dose due to 238U, 232Th, and 222Rn after the ingestion of the studied phytotherapeutic preparations, was found equal to 38 × 10-8 S·vy-1 which is less than the dose limit given by the international commission for radiological protection in it publication 56.

Relationship between Patient-Dependent Parameters and Radiation Dose Rates Measured around Patients Undergoing PET/CT Imaging Using ¹⁸F-FDG

Objectives: Patients undergoing 18F-FDG PET/CT imaging are considered external radiation sources. Accurate dose rate estimates are important for conducting realistic risk assessments and performing dose reconstruction in cases of accidental exposures. The patient radiation self-attenuation factor is assumed to be a function of the patient’s body size metrics, but we can use these metrics to predict the dose rate around the patients with accuracy. The objective of this work was first to measure the patient attenuation factor by performing direct dose rate measurements from patients undergoing PET/CT imaging studies using 18F-FDG. The second objective was to study the possible correlation between the measured dose rate constant per unit activity from the patients and their body size metrics;five metrics were tested in this work. The last objective was to measure the patients’ voiding factor. Methods: We have measured dose rates at one meter from 57 patients and noted the patient’s height (H), weight (W) and calculated patient size metrics namely: Equivalent Cylindrical Diameter (ECD), Equivalent Spherical Diameter (ESD) and the Body Mass Index (BMI). Results: The measured average dose rate was 92.2 ± 14 μSv&middot;h-1&middot;GBq-1 measured at one meter. Therefore, the dose rate constant of 92 μSv&middot;h-1&middot;GBq-1 proposed by the AAPM, TG-108 report is adequate for radiation protection purposes. There was no statistically significant correlation between the dose rate constant per unit activity and the patient body size metrics. We have measured a patient voiding factor of 0.89 ± 0.06 in comparison with 0.85 recommended by the AAPM. Conclusions: The presented data can be used by medical physicist working in nuclear medicine in formulating more accurate risk estimations resulting from radiation exposure from patients undergoing 18F-FDG PET/CT imaging.

联合布托啡诺时环泊酚在老年患者无痛胃镜检查中的有效剂量及安全性

目的探讨联合布托啡诺时环泊酚用于老年患者无痛胃镜检查的半数有效剂量(ED_(50))和95%有效剂量(ED_(95))。方法选择择期行胃镜检查的老年患者27例,均给予静脉注射布托啡诺5μg/kg至少30 s,3 min后静脉注射环泊酚至少30 s;当睫毛反射消失或者警觉/镇静评分(MOAA/S)<1分时进行胃镜检查。环泊酚最初剂量设为0.2 mg/kg,采用改良序贯等差法测定;若胃镜置入发生阳性反应,则下例患者剂量增加1级,反之则剂量减少1级,相邻剂量梯度为0.05 mg/kg。将胃镜置入发生阳性反应定义为:胃镜进入咽喉部时发生呛咳、吞咽或肢体动作。整个研究过程中,若环泊酚剂量调整有7次折返,试验终止。计算复合布托啡诺时环泊酚对无痛胃镜检查的ED_(50)、ED_(95)和相应的95%可信区间(95%CI)。结果复合布托啡诺时,环泊酚对老年患者无痛胃镜检查的ED_(50)为0.253 mg/kg(95%CI:0.219~0.290),ED_(95)为0.328 mg/kg(95%CI:0.290~0.521)。结论复合布托啡诺时,环泊酚用于老年患者无痛胃镜检查ED_(50)为0.253 mg/kg,ED_(95)为0.328 mg/kg。

不同剂量异烟肼抗结核化疗方案对药物敏感复治肺结核的疗效

目的探讨药物敏感复治肺结核患者应用不同剂量异烟肼抗结核化疗方案治疗的效果及安全性。方法选取收治的对药物敏感的复治肺结核患者97例,按照随机抽样的方式将其分为标准组(n=48)和高剂量组(n=49),标准组依据国家统一的常规剂量(异烟肼0.3 g·d^(−1))给药,高剂量组根据患者体质量决定用药量,≥70 kg者异烟肼剂量为0.5 g·d^(−1),<70 kg者为0.4 g·d^(−1),疗程为8个月。比较2组患者治疗结束后X线摄影显示肺部病灶吸收情况的变化;痰菌阴转情况;血清细胞因子水平变化[白细胞介素-18(interleukin-18,IL-18)、γ干扰素(interferon-γ,IFN-γ)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素-10(interleukin-10,IL-10)]、生活质量[肺癌生活质量评估量表(functional assessment of cancer therapylung,FACT-L)]评分以及不良反应情况。结果高剂量组病灶吸收率为87.76%,明显高于标准组的70.83%(P<0.05);治疗第1个月和第2个月,2组患者痰液转阴率比较差异无统计学意义,治疗第4个月和第8个月高剂量组患者痰菌转阴率显著高于标准组(P<0.05);治疗8个月后,2组患者血清IL-18、IFN-γ、TNF-α及IL-10水平均显著低于治疗前,且高剂量组显著低于标准组(P<0.05);2组患者FACT-L评分均显著高于治疗前,且高剂量组高于标准组(P<0.05);高剂量组不良发应发生率(18.37%)与标准组(16.67%)比较差异无统计学意义。结论对药物敏感复治肺结核采用高剂量异烟肼治疗疗效较好,能有效增强患者肺部病灶吸收,加快空洞闭合,痰液尽早恢复阴性,血清中的炎症因子水平降低,从而提高生活质量,且无明显不良反应。

减低剂量阿扎胞苷治疗老年骨髓增生异常综合征的疗效及安全性分析

目的:分析减低剂量阿扎胞苷治疗老年骨髓增生异常综合征(MDS)的疗效和安全性。方法:选取2018年1月至2022年6月于安徽省淮北矿工总医院血液内科及徐州医科大学附属医院血液内科初次诊断的92例老年MDS患者,并随机分为观察组和对照组(各46例患者)。观察组采用减低剂量阿扎胞苷100 mg/d,d1-7,以28 d为1个疗程,共用6个疗程;对照组采用标准剂量阿扎胞苷75 mg/(m^(2)·d),d1-7,以28 d为1个疗程,共用6个疗程。观察两组患者的临床疗效、总生存期及不良事件发生率。结果:两组患者临床资料差异均无统计学意义(P>0.05)。治疗后,两组患者血红蛋白和血小板水平较各组治疗前均显著升高(P<0.05)。观察组和对照组患者之间的白细胞、血红蛋白和血小板水平对比,差异均无显著统计学意义(P>0.05)。观察组完全缓解、部分缓解、血液学缓解、疾病稳定和疾病进展病例数分别为4、10、22、6和4例,总有效率为78.26%;对照组完全缓解、部分缓解、血液学缓解、疾病稳定和疾病进展病例数分别为8、12、18、4和4例,总有效率为82.61%。观察组患者总有效率略低于对照组,但差异无统计学意义(χ^(2)=0.457,P=0.254)。两种治疗方案对是否有输血依赖和低危、中危及高危组患者的疗效无显著性统计学差异(P>0.05)。对照组和观察组达到最佳治疗反应分别需要4个和6个疗程,且两组患者总生存期无显著差别(P>0.05)。观察组出现感染、Ⅲ-Ⅳ°骨髓抑制、胃肠道反应的病例数分别有4、6和2例,不良事件发生率为26.09%;对照组出现感染、Ⅲ-Ⅳ°骨髓抑制、胃肠道反应的病例数分别有6、16和6例,不良事件发生率为60.87%;对照组患者不良事件发生率显著高于观察组,差异具有统计学意义(χ^(2)=7.095,P=0.036)。结论:老年MDS患者化疗耐受性低。减低剂量阿扎胞苷治疗老年MDS患者显示出良好的疗效和安全性。

环泊酚诱导行腹部手术老年患者意识消失的半数有效量评估

目的:评估环泊酚诱导行腹部手术老年患者意识消失的半数有效量(ED 50)。方法:选取2023年4至7月在本院择期全凭静脉麻醉下行腹部手术的老年患者,采用Dixon序贯法纳入研究,初始环泊酚诱导剂量为0.3 mg/kg,相邻患者环泊酚诱导剂量梯度差值为0.03 mg/kg,如果患者意识消失则下一例患者降低1个梯度,反之则升高1个梯度,待出现7个交叉拐点则终止该研究。采用Probit概率法计算环泊酚ED 50以及95%CI。记录开始给药至给药后3 min内患者的心率(HR)、脉搏氧饱和度(SpO 2)、平均动脉压(MAP)、脑电双谱指数(BIS)、改良警觉镇静评分(MOAA/S),每30 s记录一次数据;记录给药后患者低血压、心动过缓、呼吸抑制、注射痛情况和诱导期间环泊酚总剂量。结果:共纳入26例,年龄65~78岁,BMI 18.0~28.0 kg/m 2,ASA分级Ⅱ~Ⅲ级。环泊酚诱导致老年患者意识消失的ED 50(95%CI)为0.267(0.250~0.284)mg/kg。与麻醉诱导即刻比较,给药后30、60、90、120、150、180 s时的MOAA/S评分、BIS、MAP明显下降(P<0.05),HR无明显变化;患者均未发生注射痛、低血压和需要处理的心动过缓。结论:环泊酚诱导行腹部手术老年患者意识消失的ED 50(95%CI)为0.267(0.250~0.284)mg/kg。

Assessment of ESAK and ED for Adult’s Patients Examined by Computed Radiography

This study designed to evaluate the entrance surface air kerma (ESAK) to the patient during X-ray examination to the skull antero-posterior (AP), skull Lateral (LAT), chest postero-anterior (PA), Lumber spine AP/LAT and Pelvis AP. Totally, 408 patients were included in this study using computed radiography (CR) in different three hospitals in Khartoum;five X-ray machines were covered. The entrance surface air kerma (ESAK) was calculated for each patient from the exposure parameters using different peak tube voltages. Patient’s data such as (age and weight) and exposure parameters (kVp) and (mAs) were recorded. The result obtained showed that, the entrance surface air kerma ranged from 0.88 to 3.30 mGy for Skull (AP), 0.588 to 1.87 mGy for skull (LAT), 0.03 to 2 mGy for chest PA, 1.50 to 3.40 mGy Lumbar spine AP, 2.60 to 5.15 mGy for Lumbar spine (LAT), and 1.05 to 4.40 mGy for Pelvis. This study provides additional data that can help the regulatory authority to establish reference dose level for diagnostic radiology in Sudan. This study recommends that the CR operator must be used to optimize the patient dose by using the best strategies available for reducing radiation dose. Computed radiography must be used with high level training for medical staff to reduce the dose;each radiology department should implement a patient dose measurement quality assurance programme. Doses to the patients should be regularly monitored and the proposed national DRLs should be taken as guidance for optimization.

不同剂量瑞马唑仑全麻诱导在老年腹腔镜手术患者的价值

目的:分析不同剂量瑞马唑仑全麻诱导在老年腹腔手术患者中的应用价值。方法:选130例患者随机分为第1组(n=43)、第2组(n=43)、第3组(n=44),均采用瑞马唑仑行全麻诱导,分别静注0.2/0.3/0.4mg/kg。比较两组相关指标差异。结果:第1组的瑞马唑仑补救例数较第2、3组高(P<0.05);第1组的诱导开始至BIS≤60的时间>第2组>第3组(P<0.05);气管插管后即刻、气管插管后5min,第1组血浆NE、E、Cor水平均较第2、3组高(P<0.05);气管插管后5min,第1组HR、MAP均较第2、3组高(P<0.05);第3组不良反应发生率高于第1、2组(P<0.05)。结论:0.3mg/kg是瑞马唑仑用于老年腹腔镜手术患者全麻诱导的适宜剂量。

丙泊酚及不同剂量瑞马唑仑对舒芬太尼抑制老年患者气管插管反应半数有效剂量的影响

目的应用序贯法探讨丙泊酚或不同剂量瑞马唑仑对舒芬太尼抑制老年患者气管插管反应的半数有效剂量(50%effective dose,ED_(50))的影响。方法选择2022年10至12月在气管插管全身麻醉下接受择期手术的老年患者,美国麻醉医师协会(American Society of Anesthesiologists,ASA)分级Ⅰ、Ⅱ级,年龄65~80岁,将患者采用随机数字表法分为4组:丙泊酚组(P组,诱导时给予丙泊酚2mg/kg)和瑞马唑仑组(R1、R2、R3组,诱导时分别静脉注射瑞马唑仑0.2、0.3、0.4mg/kg)。麻醉诱导时给予Dixon序贯法设定剂量的舒芬太尼后,静脉注射丙泊酚或相应剂量瑞马唑仑及顺式阿曲库铵0.15mg/kg,待4个成串刺激(train of four,TOF)计数为0时行气管插管。若气管插管反应阳性,则下一例患者舒芬太尼剂量提高1个浓度梯度,否则降低1个浓度梯度,各相邻浓度之间的比为1∶1.1,直至出现7个转折点终止研究。采用Probit回归分析计算舒芬太尼抑制老年患者气管插管反应ED_(50)和95%有效剂量(95%effective dose,ED_(95))以及相应的95%置信区间(confidenceinterval,CI)。记录所有患者低血压、心动过缓、注射痛等不良反应的发生情况。结果本研究共纳入老年患者113例,P、R1、R2、R3组分别24、28、30、31例。丙泊酚2mg/kg或0.2、0.3、0.4mg/kg瑞马唑仑时舒芬太尼抑制老年患者气管插管反应的ED_(50)和ED_(95)及相应95%CI分别为:P组ED_(50)为0.236μg/kg(95%CI:0.218~0.256),ED_(95)为0.266μg/kg(95%CI:0.250~0.398);R1组ED_(50)为0.284μg/kg(95%CI:0.265~0.309),ED_(95)为0.329μg/kg(95%CI:0.306~0.478);R2组ED_(50)为0.239μg/kg(95%CI:0.221~0.260),ED_(95)为0.282μg/kg(95%CI:0.261~0.415);R3组ED_(50)为0.198μg/kg(95%CI:0.182~0.211),ED_(95)为0.231μg/kg(95%CI:0.216~0.303)。与P组相比,R1、R2、R3组低血压、心动过缓、注射痛发生率较低(P<0.05)。R2组舒芬太尼ED_(50)与P组相类似,但低血压、注射痛发生率与P组相比较低。结论随着瑞马唑仑剂量的增加,舒芬太尼抑制老年患者气管插管反应的ED_(50)逐渐降低;在ED_(50)相近的情况下,瑞马唑仑相较于丙泊酚诱导的低血压、心动过缓、注射痛发生率更低,因而在老年患者气管插管全身麻醉中,使用瑞马唑仑诱导更具有优势。

乌灵胶囊联合小剂量喹硫平用于失眠伴焦虑抑郁高龄老年患者的疗效分析

目的 探讨乌灵胶囊联合小剂量喹硫平治疗高龄老年失眠伴焦虑抑郁患者的疗效和安全性。方法 回顾性分析2020年6月-2022年12月在我院门诊就诊或住院治疗的96例失眠伴焦虑抑郁高龄老年(≥80岁)患者的临床资料。根据治疗方案的不同将患者分为乌灵胶囊组(0.99 g,每天3次,34例)、喹硫平组(25~50 mg,每晚1次,30例)和联合组(同时服用乌灵胶囊和喹硫平,用法用量同单药组,32例)。比较3组患者治疗前和治疗8周后的睡眠监测指标(总睡眠时间、睡眠效率、睡眠潜伏期、觉醒次数)、匹兹堡睡眠质量指数量表(PSQI)评分、14项汉密尔顿焦虑量表(HAMA-14)评分、17项汉密尔顿抑郁量表(HAMD-17)评分、简易智能精神状态量表(MMSE)评分、血清白细胞介素1β(IL-1β)和肿瘤坏死因子α(TNF-α)水平,以及疗效和不良反应发生情况。结果 与治疗前比较,3组患者治疗后的总睡眠时间、睡眠效率、MMSE评分均显著延长或升高(P<0.05),睡眠潜伏期、觉醒次数、PSQI评分、HAMA-14评分、HAMD-17评分、血清IL-1β和TNF-α水平均显著缩短或降低(P<0.05),喹硫平组患者的睡眠潜伏期、觉醒次数、HAMA-14评分、HAMD-17评分、血清TNF-α水平均明显短于或低于乌灵胶囊组,且联合组各定量指标均显著优于喹硫平组和乌灵胶囊组(P<0.05)。联合组患者的治疗总有效率显著高于喹硫平组和乌灵胶囊组(P<0.05),3组患者的总不良反应发生率比较差异无统计学意义(P>0.05)。结论 乌灵胶囊联合小剂量喹硫平用于高龄老年失眠伴焦虑抑郁患者的疗效优于各药单用,不良反应未见明显增加。

个体化给药方案对重症患者万古霉素血药谷浓度和肾功能的影响

目的考察个体化给药方案对重症患者万古霉素血药谷浓度(以下简称“谷浓度”)和肾功能的影响。方法临床药师参考相关指南推荐和Vancomycin Calculator软件计算结果,以体质量和肌酐清除率为自变量制定包含了负荷剂量和维持剂量的重症患者万古霉素个体化给药方案。采用回顾性研究方法,选取2018年7月-2021年12月入住广州医科大学附属第二医院重症医学科使用该方案的患者作为试验组,将该科室2015年1月-2018年6月应用万古霉素治疗并行血药浓度监测的患者作为对照组,比较2组患者万古霉素谷浓度的分布差异和用药后急性肾损伤(AKI)的发生率,并分析试验组患者血肌酐的变化情况。结果试验组纳入197例患者,对照组纳入144例患者。2组患者的性别、年龄、体质量、急性生理学及慢性健康状况评分系统Ⅱ评分、慢性肾功能不全患者占比等临床资料比较,差异均无统计学意义(P>0.05)。2组患者主要的感染部位(包括肺部、尿路、腹腔、血流、中枢神经系统)占比和治疗类型(目标治疗/经验性治疗)占比的差异均无统计学意义(P>0.05)。2组患者万古霉素理想谷浓度(15~20μg/mL)的达标率和谷浓度>20μg/mL的患者占比差异均无统计学意义(P>0.05),而目标谷浓度(10~20μg/mL)的达标率和谷浓度<10μg/mL的患者占比差异均有统计学意义(P<0.05)。试验组合并慢性肾功能不全患者目标谷浓度的达标率显著高于对照组(P<0.05)。2组患者用药后AKI的发生率、万古霉素相关AKI的发生率差异均无统计学意义(P>0.05)。用药时间≥7 d的试验组患者在用药第7天时的血肌酐水平较用药第3天时显著升高(P<0.05)。结论该个体化给药方案能够提高重症患者尤其是合并慢性肾功能不全的重症患者万古霉素首次规范监测时目标谷浓度的达标率,且与既往经验性用药相比不增加重症患者肾损伤的风险。

Cumulative radiation exposure from diagnostic imaging in intensive care unit patients

AIM:To quantify cumulative effective dose of intensive care unit(ICU)patients attributable to diagnostic imaging.METHODS:This was a prospective,interdisciplinary study conducted in the ICU of a large tertiary referral and level 1 trauma center.Demographic and clinical data including age,gender,date of ICU admission,primary reason for ICU admission,APACHE Ⅱ score,length of stay,number of days intubated,date of death or discharge,and re-admission data was collected on all patients admitted over a 1-year period.The overall radiation exposure was quantified by the cumulative effective radiation dose(CED)in millisieverts(mS v)and calculated using reference effective doses published by the United Kingdom National Radiation Protection Board.Pediatric patients were selected for subgroupanalysis.RESULTS:A total of 2737 studies were performedin 421 patients.The total CED was 1704 m Sv with a median CED of 1.5 mS v(IQR 0.04-6.6 mS v).Total CED in pediatric patients was 74.6 mS v with a median CED of 0.07 mS v(IQR 0.01-4.7 mS v).Chest radiography was the most commonly performed examination accounting for 83% of all studies but only 2.7% of total CED.Computed tomography(CT)accounted for 16% of all studies performed and contributed 97% of total CED.Trauma patients received a statistically significant higher dose [median CED 7.7 mS v(IQR 3.5-13.8 mS v)] than medical [median CED 1.4 m Sv(IQR 0.05-5.4 m Sv)] and surgical [median CED 1.6 mS v(IQR 0.04-7.5 mS v)] patients.Length of stay in ICU [OR = 1.12(95%CI:1.079-1.157)] was identified as an independent predictor of receiving a CED greater than 15 mS v.CONCLUSION:Trauma patients and patients with extended ICU admission times are at increased risk of higher CEDs.CED should be minimized where feasible,especially in young patients.

Relationship between patient centering,mean computed tomography numbers and noise in abdominal computed tomography:Influence of anthropomorphic parameters

AIM:To determine the influence of anthropomorphic parameters on the relationship between patient centering,mean computed tomography(CT) numbers and quantitative image noise in abdominal CT.METHODS:Our Institutional Review Board approved study included 395 patients(age range 21-108,years;male:female = 195:200) who underwent contrast-enhanced abdominal CT on a 16-section multi-detector row scanner(GE LightSpeed 16).Patient centering in the gantry isocenter was measured from the lateral localizer radiograph(off center S = patient off centered superior to isocenter;off center I = patient off centered inferior to isocenter).Mean CT numbers(Hounsfield Units:HU) and noise(standard deviation of CT numbers:SD) were measured in the anterior(aHU,aSD) and posterior(pHU,pSD) abdominal wall subcutaneous fat and liver parenchyma(LivHU,LivSD) at the level of the porta hepatis.Patients' age,gender,weight,body mass index and maximal anteroposterior diameter were recorded.The data were analyzed using linear regression analysis.RESULTS:Most patients(81%;320/395) were not correctly centered in the gantry isocenter for abdominal CT scanning.Mean CT numbers in the abdominal wall increased significantly with an increase in the offcentering distance,regardless of the direction of the off-center(P < 0.05).There was a substantial increase in pSD(P = 0.01) and LivSD(P = 0.017) with off-centering.Change in mean CT numbers and image noise along the off-center distance was influenced by the patient size(P < 0.01).CONCLUSION:Inappropriate patient centering for CT scanning adversely affects the reliability of mean CT numbers and image noise.