Application of Linear Accelerator on Boarding Kilovolt Fan Beam CT and Megavolt Cone Beam CT System on Set-up Errors During Radiation Treatment / 肿瘤防治研究

Objective To quantify the setup errors for the different anatomical sites of patients who received intensity-modulated radiotherapy (IMRT) with linear accelerator on-board kilovolt fan beam CT(kV-FBCT) as non-isocenter IGRT and megavolt cone beam CT (MV-CBCT) as isocenter IGRT. Methods A retrospective analysis was performedon 70 patients who underwent radiotherapy, kV-FBCT, and/or MV-CBCT scans after each routine setup prior to IMRT. The average displacement (M), systematic error (Σ), and random error (б) at different treatment sites in the left-right, anterior-posterior, and cranial-caudal directions were calculated according to the individual displacements. The formula 2.5Σ+0.7б was used to estimate the PTV margin in respective direction. For each single patient, the root mean square in three directions was used as 3D displacement. Results A total of 1130 displacements were recorded in the 70 patients. The PTV margin was estimated to be 1.9-3.1 mm in head and neck cancer, 2.8-5.1 mm in thoracic cancer, 4.6-5.1 mm in breast cancer, 3.0-5.5 mm in upper abdominal cancer, and 3.5-6.8 mm in pelvic tumor. For the 3D mean displacements, the head and neck, thoracic, breast, upper abdominal, and pelvic cancer were 2.4±1.0, 4.0±1.6, 4.1±2.0, 4.6±2.1, and 4.6±2.1 mm, respectively. The average 3D displacement obtained by kV-FBCT and MV-CBCT were 4.1 and 3.4 mm, respectively (P=0.212). Conclusion The quantitative setup-error data can be obtained using linear accelerator on-board FBCT, and the non-isocenter IGRT induced set-up error cannot be negligible.

Construction of a risk prediction and evaluation system for postoperative incisional infection after spinal surgery / 中华创伤骨科杂志

Objective:To construct a risk prediction and assessment system for incisional infection after spinal surgery.Methods:Based on the failure mode and effect analysis (FMEA), risk factors and assessment indicators of postoperative incisional infection in spinal surgery were sorted out through literature search followed by expert consultation using the Delphi expert consultation method. After three-level assessment indicators were selected according to their importance and expert opinions and assigned by different scores, a risk prediction and evaluation system was constructed for postoperative incisional infection after spinal surgery.Results:The 2 rounds of expert consultation questionnaire resulted in an effective response rate of 100%. The degree of expert consultation authority was 0.85, showing high reliability; the Kendall coordination coefficients of expert consultation ranged from 0.525 to 0.686, showing good coordination ( P<0.05). The three-level assessment indicators consisted of 3 primary, 18 secondary and 54 tertiary ones. After statistical analyses of the important risk indicators selected which consisted of 6 preoperative evaluation ones and 18 postoperative evaluation ones, 6 preoperative and 12 postoperative predictive indicators were obtained. The values of risk priority number (RPN) were calculated for high, medium and low risks for postoperative incisional infection using a semi-quantitative method. Conclusion:A self-designed system has been constructed for risk prediction and assessment of incisional infection after spinal surgery based on expert consultation and FMEA method.

Household transmission of COVID-19, Shenzhen, January-February 2020

Coronavirus disease 2019 has led to more than three million cases globally. Since the first family cluster of COVID-19 cases identified in Shenzhen in early January, most of the local transmission occurred within household contacts. Identifying the factors associated with household transmission is of great importance to guide preventive measures.

Evolving Epidemiology and Effect of Non-pharmaceutical Interventions on the Epidemic of Coronavirus Disease 2019 in Shenzhen, China

Previous studies have demonstrated the characteristics of patients with 2019 novel coronavirus disease (COVID-19). However, the effect of non-pharmaceutical interventions on the epidemic in Shenzhen, China remains unknown. Individual data of 417 cases were extracted from the epidemiological investigations and the National Infectious Disease Information System between January 1, 2020 and February 29, 2020. On the basis of important interventions, the epidemic was divided into four periods (January 1-15, January 16-22, January 23-February 5 and after February 6). We used a susceptible-exposed-infectious-asymptomatic-recovered model to evaluate the effect of interventions. Results suggested that about 53.7% were imported from Wuhan. The median age was 47 years and 52.8% were women. Severity risk increased with age and associated with male and co-existing disorders. The attack rate peaked in the third period and drastically decreased afterwards across sex, age groups and geographic regions. Children younger than 5 years showed a higher attack rate than those aged of 6~19. The effective reproductive number decreased from 1.44 to 0.05 after the highest level emergency response since January 23. Overall, the non-pharmaceutical interventions have effectively mitigated the COVID-19 outbreak in Shenzhen, China. These findings may facilitate the introduction of public health policies in other countries and regions.

Epidemiological and clinical characteristics of COVID-19 in Shenzhen, the largest migrant city of China

We conducted a retrospective study among 417 confirmed COVID-19 cases from Jan 1 to Feb 28, 2020 in Shenzhen, the largest migrant city of China, to identify the epidemiological and clinical features in settings of high population mobility. We estimated the median incubation time to be 5.0 days. 342 (82.0%) cases were imported, 161 (38.6%) cases were identified by surveillance, and 247 (59.2%) cases were reported from cluster events. The main symptoms on admission were fever and dry cough. Most patients (91.4%) had mild or moderate illnesses. Age of 50 years or older, breathing problems, diarrhea, and longer time between the first medical visit and admission were associated with higher level of clinical severity. Surveillance-identified cases were much less likely to progress to severe illness. Although the COVID-19 epidemic has been contained in Shenzhen, close monitoring and risk assessments are imperative for prevention and control of COVID-19 in future. Article Summary LineWe characterized epidemiological and clinical features of a large population-based sample of COVID-19 cases in the largest migrant city of China, and our findings could provide knowledge of SARS-CoV-2 transmission in the context of comprehensive containment and mitigation efforts in similar settings.

Epidemiology and Transmission of COVID-19 in Shenzhen China: Analysis of 391 cases and 1,286 of their close contacts

BackgroundRapid spread of SARS-CoV-2 in Wuhan prompted heightened surveillance in Shenzhen and elsewhere in China. The resulting data provide a rare opportunity to measure key metrics of disease course, transmission, and the impact of control. MethodsThe Shenzhen CDC identified 391 SARS-CoV-2 cases from January 14 to February 12, 2020 and 1286 close contacts. We compare cases identified through symptomatic surveillance and contact tracing, and estimate the time from symptom onset to confirmation, isolation, and hospitalization. We estimate metrics of disease transmission and analyze factors influencing transmission risk. FindingsCases were older than the general population (mean age 45) and balanced between males (187) and females (204). Ninety-one percent had mild or moderate clinical severity at initial assessment. Three have died, 225 have recovered (median time to recovery is 21 days). Cases were isolated on average 4.6 days after developing symptoms; contact tracing reduced this by 1.9 days. Household contacts and those travelling with a case where at higher risk of infection (ORs 6 and 7) than other close contacts. The household secondary attack rate was 15%, and children were as likely to be infected as adults. The observed reproductive number was 0.4, with a mean serial interval of 6.3 days. InterpretationOur data on cases as well as their infected and uninfected close contacts provide key insights into SARS-CoV-2 epidemiology. This work shows that heightened surveillance and isolation, particularly contact tracing, reduces the time cases are infectious in the community, thereby reducing R. Its overall impact, however, is uncertain and highly dependent on the number of asymptomatic cases. We further show that children are at similar risk of infection as the general population, though less likely to have severe symptoms; hence should be considered in analyses of transmission and control.

The key points of development trend and clinical practice of global donation after cardiac death / 器官移植

Organ transplantation has brought hope for healing of patients with end-stage organ failure. However, the shortage of human organs has become one of the important factors that severely restrict the development of human organ transplantation. Donation after cardiac death (DCD) is a safe way to expand the source of donors. While trying to make extensive effort to increase the quantity of donation after brain death (DBD), countries attempt to grasp the opportunity of DCD when conditions permit. In this article, the historical background and global development trend of DCD, fundamental conditions for the implementation of controllable DCD, key issues and ethical review in the practice of controllable DCD were discussed.

Genomic characterisation of a colistin-resistant Klebsiella pneumoniae ST11 strain co-producing KPC-2, FloR, CTX-M-55, SHV-12, FosA and RmtB causing a lethal infection.

OBJECTIVES: The aim of this study was to characterise the genomic and phenotypic characteristics of a colistin-resistant Klebsiella pneumoniae isolate causing a lethal infection that was phenotypically resistant to carbapenems and colistin. METHODS: Whole-genome sequencing was performed on an Illumina HiSeq 2500 platform. Genome annotation was performed by the Rapid Annotation using Subsystem Technology (RAST) server. Antimicrobial resistance genes and plasmid replicons were identified using ResFinder 2.1 and PlasmidFinder 1.3, respectively. The isolate was further characterised by plasmid analysis using S1-PFGE and Southern blot hybridisation with a digoxigenin-labelled probe specific for blaKPC. RESULTS: The genome of K. pneumoniae LSK16 consists of a 6.02-Mbp chromosome and one plasmid. Multilocus sequence typing (MLST) identified the isolate as ST11, a close variant of the international pandemic clone ST258. The isolate was found to harbour blaKPC-2, blaSHV-12, blaCTX-M-55, floR and rmtB genes. Of note, a novel fosfomycin resistance glutathione transferase variant was confirmed by PCR and sequencing, with 98.6% (136/138) identity to fosA. Moreover, amino acid substitutions in PmrB (R256G) and PhoQ (D150G) were identified in LSK16, confirming the polymyxin/colistin resistance, although the isolate was negative for mcr genes. Southern blotting and plasmid analysis revealed that the blaKPC-2 gene was harboured on a non-conjugative IncR plasmid (˜165kb). CONCLUSION: Here we identified a colistin-resistant K. pneumoniae ST11 strain co-producing KPC-2, FloR, CTX-M-55, SHV-12 and RmtB causing a lethal infection. This study provides new genomic insights into the diversity of K. pneumoniae ST11 prevalent in Zhejiang Province, China.

Correlation between single nucleotide polymorphism of TET2 gene and susceptibility and prognosis of sepsis / 中华急诊医学杂志

Objective@#To investigate the association of SNPs in TET2 gene with the susceptibility and prognosis of sepsis.@*Methods@#Ninety-nine patients diagnosed with sepsis and 107 controls were enrolled in the study. The septic patients were further divided into survivors (56 cases) and non-survivors (43 cases) according to the outcome of 28-day hospitalization. Patients without sepsis after major surgery were enrolled as the controls. The genotypes of the five loci (rs6839705, rs7670522, rs7679673, rs7698522 and rs10010325) with high minor allele frequency in the TET2 were screened according to the existing research reports and the SNP database of the NCBI website. The five loci were detected by TaqMan probe based allelic discrimination assays using real-time polymerase chain reaction (PCR). The data were calculated for genetic association study through χ2 test and Fisher’s exact probability method.@*Results@#There was no significant difference in genotype frequencies of the five tested SNPs in TET2 gene between septic patients and controls or between survivors and non-survivors in septic patients (P > 0.05). Furthermore, the allelic frequencies of the five SNPs between septic patients and controls or between survivors and non-survivors in septic patients also had no significant difference (P > 0.05).@*Conclusions@#This study showed that the five SNPs in TET2 gene (rs6839705, rs7670522, rs7679673, rs7698522, and rs10010325) were not associated with the susceptibility and prognosis of sepsis, which needs to be further confirmed by large-sample studies.

Correlation between single nucleotide polymorphism of TET2 gene and susceptibility and prognosis of sepsis / 中华急诊医学杂志

Objective To investigate the association of SNPs in TET2 gene with the susceptibility and prognosis of sepsis.Methods Ninety-nine patients diagnosed with sepsis and 107 controls were enrolled in the study.The septic patients were further divided into survivors (56 cases) and non-survivors (43 cases) according to the outcome of 28-day hospitalization.Patients without sepsis after major surgery were enrolled as the controls.The genotypes of the five loci (rs6839705,rs7670522,rs7679673,rs7698522 and rs10010325) with high minor allele frequency in the TET2 were screened according to the existing research reports and the SNP database of the NCBI website.The five loci were detected by TaqMan probe based allelic discrimination assays using real-time polymerase chain reaction (PCR).The data were calculated for genetic association study through x2 test and Fisher's exact probability method.Results There was no significant difference in genotype frequencies of the five tested SNPs in TET2 gene between septic patients and controls or between survivors and non-survivors in septic patients (P ＞ 0.05).Furthermore,the allelic frequencies of the five SNPs between septic patients and controls or between survivors and non-survivors in septic patients also had no significant difference (P ＞ 0.05).Conclusions This study showed that the five SNPs in TET2 gene (rs6839705,rs7670522,rs7679673,rs7698522,and rs10010325) were not associated with the susceptibility and prognosis of sepsis,which needs to be further confirmed by large-sample studies.

Evaluation of the right ventricular function in patients with pneumoconiosis by echocardiography / 中华劳动卫生职业病杂志

Objective@#To investigate right ventricular function in patients with pneumoconiosis, and to provide a basis for quantitative diagnosis and treatment of pneumoconiosis in clinical practice.@*Methods@#A total of 43 patients with pneumoconiosis who were hospitalized consecutively in Shijiazhuang Prevention and Treatment Center for Occupational Diseases from May 2015 to May 2016 were enrolled, and according to the stage of pneumoconiosis, they were divided into stage I group with 16 patients, stage II group with 14 patients, and stage III group with 13 patients. A total of 16 healthy subjects were enrolled as control group. Echocardiography was performed and the relevant parameters were recorded, i.e., right ventricular transverse diameter (RVTD), tricuspid annular plane systolic excursion (TAPSE), and right ventricular myocardial performance index(Tei index).@*Results@#There were significant differences in Tei index and TAPSE between all groups (P <0.05) except between the stage I group and the control group in terms of Tei index (P>0.05) and between the stage I group and the stage II group in terms of TAPSE (P>0.05). Right ventricular Tei index was negatively correlated with TAPSE (r=-0.547,P<0.05).@*Conclusion@#A combination of right ventricular Tei index and TAPSE can be used for early quantitative evaluation of right ventricular function in patients with pneumoconiosis.

Application of incisional negative pressure wound therapy (iNPWT) for primary incision closure: now and future / 中华创伤骨科杂志

It has long been one significant focus in the field of surgery to reduce postoperative incisional complications.Recently,incisional negative pressure wound therapy (iNPWT),which was designed to reduce the incidence of incisional complications,has gradually been applied for primary incision closure.This article reviews the relevant basic and clinical studies to elucidate the mechanism of iNPWT and its clinical safety and efficacy,and answers some fundamental questions regarding clinical application of iNPWT.

Application of placebo acupuncture in randomized controlled trials in the past 10 years in foreign countries / 中国针灸

The application of placebo acupuncture in randomized controlled trials in the past 10 years (2004-2014) in foreign countries was systematically reviewed to summarize the design of placebo acupuncture; according to category of diseases, advantages and disadvantages were analyzed to explore an ideal placebo acupuncture set. By retrieval in PubMed, EMBASE and OVID databases, the clinical study literature which met the inclusion criteria was searched, and the category of diseases, design of placebo acupuncture and clinical efficacy were analyzed. Totally 29 articles were included. The pain was the leading disease in category of diseases; the most commonly used application of placebo acupuncture design was telescopiform sliding blunt needle, accounting for 45. 16%; the treatment locations were non-acupoints mostly; in the needling depth, approximately 60. 00% selected non-penetrating needling and 26. 67% selected superficial needling; 28 articles indicated that acupuncture and placebo acupuncture had clinical effects, accounting for 96. 55%; 37. 93% of articles indicated acupuncture was superior to placebo acupuncture and 37. 93% of articles indicated acupuncture was not superior to placebo acupuncture. It is concluded that the design of placebo acupuncture should consider multiple factors, including main symptoms, operability, security, blinding and specific effects, and the objective indices should be selected for outcome evaluation.

Risk factors and prognosis of acute kidney injury in elderly patients with sepsis / 中华老年医学杂志

Objective To investigate the risk factors and prognosis of acute kidney injury (AKI) in elderly patients with sepsis in intensive care unit (ICU).Methods Clinical data of 108 elderly patients diagnosed as sepsis admitted in ICU in our hospital,from May 2010 to May 2014 were analyzed retrospectively.Patients were divided into two groups:the AKI group and the non-AKI group.Clinical characteristics,laboratory and physiologic data were compared between groups.Multivariate Logistic regression analysis was used to analyze the independent risk factors for AKI in these patients,and clinical outcome was retrospectively analyzed.Results Among the 108 elderly patients,60 patients developed AKI and the incidence was 55.6％.Baseline glomerular filtration rate (GFR) and mean arterial pressure (MAP) were lower in the AKI group than in non-AKI group (t=4.536 and 3.28).Prothrombin time (PT) (t=3.053),multiple organ dysfunction score (MODS) (t =2.201),acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score (t=3.423),the incidence of septic shock (x2 =5.400) and patients undergoing surgical operation within two weeks (x2 =5.625) were higher or longer in AKI group than in non-AKI group (all P＜0.05).Multivariate Logistic regression analysis showed that MAP (OR =0.833),baseline GFR (OR=0.776),MODS (OR=2.039) were independent risk factors for AKI occurrence.Hospital mortality,length of stay in ICU and hospitalization time were higher or longer in AKI group than in non-AKI group (P=0.001,0.026 and 0.042).Conclusions MAP,baseline GFR and MODS are the independent risk factors for AKI occurrence in elderly adults with sepsis in ICU.Hospital mortality,length of stay in ICU and hospitalization time are increased in sepsis patients combined with AKI.

Preparation of calcium titanate coating on titanium and its biosafety / 医学研究生学报

requirement of medical materials for hemolysis experiment (<5%) .MTT assay showed that , after 4 days of culture , the optical densi-ties were 0.498 ±0.218 and 0.566 ±0.266 in the 120℃12 h and 24 h groups and 0.668 ±0.268 and 0.769 ±0.213 in the 150℃12 h and 24 h groups, while after 8 days, the optical densities were 0.767 ±0.267 and 0.836 ±0.236 in the 120℃12 h and 24 h groups and 0.765 ±0.265 and 0.903 ±0.303 in the 150℃12 h and 24 h groups, all significantly higher than in the non-CaTiO3 group at 4 (0.341 ±0.143) and 8 days (0.731 ±0.121) (P<0.05). Conclusion The CaTiO3 coating on titanium is neither mutagenic nor hemolytic and has no toxicity on osteoblasts .Instead, it can promote the proliferation of osteoblasts , and therefore is a valuable coating material for implants .

Prevalence and risk factors of Enterobius vermicularis among preschool chil-dren in kindergartens in Luohu District,Shenzhen City / 中国血吸虫病防治杂志

Objective To understand the prevalence and risk factors of Enterobius vermicularis among preschool children in kindergartens in Luohu District Shenzhen City. Methods A total of 489 children in 6 kindergartens were selected by the stratified sampling method and investigated for E. vermicularis infection by the cellophane anal swab technique. The information of sanitary condition of the kindergartens personal hygiene and family hygiene were investigated by questionnaire. Results The infection rate of E. vermicularis was 10.2% 50/489 . The single factor analysis indicated that the following factors might re?lated to the infection the different classes of kindergartens grades ground of bed room private toilet types of taps and beds bed management education levels of parents frequency of shower and washing anus and washing hands before meal and after WC. The multivariate Logistic analysis indicated that the bed management education level of mothers frequency of washing anus and private toilet were independent risk factors for E. vermicularis infection. Conclusion To control the infection of E. vermicularis the circumstance and management of kindergartens parents knowledge of E. vermicularis infection and chil?dren s healthy habit need improve.

Constipation predominant irritable bowel syndrome treated with acupuncture for regulating the mind and strengthening the spleen: a randomized controlled trial / 中国针灸

<p><b>OBJECTIVE</b>To observe the clinical efficacy on constipation predominant irritable bowel syndrome (IBS-C) treated with acupuncture for regulating the mind and strengthening the spleen and the impacts on the quality of life in the patients.</p><p><b>METHODS</b>Sixty patients of IBS-C were randomized into two groups. In the acupuncture group (30 cases), acupuncture was applied to Tianshu (ST 25), Zusanli (ST 36), Shangjuxu (ST 37), Taichong (LR 3), Sanyinjiao (SP 6), Yintang (GV 29) and Baihui (GV 20), once a day, 5 treatments a week and 4 weeks treatment as one session. In the western medication group (30 cases), lactulose oral solution was prescribed, 15 mL each time, three times a day, 4 weeks treatment as one session. The symptom grade scale and the quality of life scale (IBS-QOL) were adopted to observe the changes in clinical symptoms and quality of life before treatment, after treatment and 2-month follow-up after treatment in the patients of the two groups separately.</p><p><b>RESULTS</b>(1) Clinical symptom score: the difference in the symptom score at each time point was significant statistically in intra-group comparison (P < 0.01). In 1 week, 4 weeks of treatment and 2 months after treatment, the clinical symptom scores in the acupuncture group were lower than those in the western medication group (P < 0.05, P < 0.01). (2) IBS-QOL score after treatment was improved as compared with that before treatment in the two groups (P < 0.01). The improvement of IBS-QOL at 2 months after treatment in the acupuncture group was apparently superior to the western medication group (P < 0.05). (3) The total effective rate was 90.0% (27/30) in the acupuncture group and was 83.3% (25/30) in the western medication group. The overall efficacy in the acupuncture group was better than that in the western medication group (P < 0.01).</p><p><b>CONCLUSION</b>Acupuncture for regulating the mind and strengthening the spleen significantly relieves the clinical symptoms of IBS-C and improves QOL of patients. The total efficacy is superior to lactulose oral solution and presents a certain of long-term efficacy.</p>

A clinical trial of ketogenic diet in patients with acute spinal cord injury: safety and feasibility / 南方医科大学学报

<p><b>OBJECTIVE</b>To conduct a clinical trial of ketogenic diet (KD) in patients with acute spinal cord injury (SCI) and evaluate its safety and feasibility by measuring blood ketone bodies and blood glucose levels.</p><p><b>METHOD</b>Ten patients with acute SCI were recruited in the trial during the period from May, 2012 to October, 2013. The patients received a standard KD after fasting for 48 h. The levels of blood ketone, blood glucose and uric ketone were tested daily, and routine blood examination, electrolytes, liver and kidney function, body mass index (BMI), sensory and motor function, and adverse reactions were monitored weekly to assess the safety and feasibility of KD.</p><p><b>RESULTS</b>KD treatment lasted for a mean of 12.9 days (4 to 29 days) in these patients. In all the patients, blood ketone level increased during the fasting and maintained a level above 2.0 mmol/L after taking KD, while the uric ketone level ranged from +++ to ++++. The blood glucose level was in the normal range during KD. Except for blood chloride level and BMI, routine blood test results, electrolytes, liver and kidney function showed no significant changes after KD. No significant changes were observed in the sensation of light touch and pinprick. The average motor ASIA score increased from 33.3 to 35.1 after KD. Gastrointestinal dysfunction (diarrhea, nausea, poor appetite, gastric pain, and abdominal distension) was recorded in 5 patients, hypoglycemia occurred in one patient early after KD, and one patient experienced urticaria during KD. All the adverse reactions were relieved after symptomatic treatments.</p><p><b>CONCLUSION</b>This preliminary clinical trial demonstrated that KD could increase ketone bodies level and maintain a normal blood glucose level, suggesting its safety and feasibility in patients with acute SCI.</p>

Internal fixation of femoral neck fractures in the elderly / 中华创伤骨科杂志

Objective To evaluate the outcome of the old patients who were treated for femoral neck fractures in our hospital during 2000-2007. Methods A retrospective study was conducted to evaluate outcomes of the 139 old patients who had received internal fixation for femoral neck fractures in our department during 2000-2007. The mechanism of injury, duration between injury and hospitalization, severity of fracture, anamnesis, time of hospital stay, anaesthesia, operation, postoperative complications, fracture healing, in-cidence of avascular necrosis of femoral head, failure of fixation, and functional restoration of the patients were documented. Results Fracture healing was found in 126 cases (90.6%). Time to healing ranged from 2 to 20 months (average, 6.2 months). Failure of fixation and nonunion were found in 13 cases (9.4%). Avascular necrosis of femoral head occurred in 9 cases (6.5% ). Of them, 81 patients(58.3%) restored their gait as normal as before whereas 50 patients(36.0%) walked with crutches. Conclusions Internal fix-ation can be suggested for old patients with femoral neck fracture, considering a high rate of fracture healing and a low rate of avascular necrosis of the femoral head. Early operation is recommended if the general con-dition of the patient has been well controlled.

The use of modified apnea test in the brain death evaluation / 中华急诊医学杂志

Objective To evaluate the safety and feasibility of the modified apnea test (MAT) for brain death evaluation. Method A prospective, controlled clinical study was carried out. Forty-three patients with suspected brain death underwent a total of 85 MATs. The patient's spontaneous breathing, hemodynamics and oxy genarion were monitored during MAT; arterial blood pH, PaCO2, PaO2 were measured before and after the MAT. Paired t test was used for statistical analysis to determine significant differences in measurements before and after MAT on the same patient. The Wilcoxon Signed-Rank Test was used to determine statistical significance for skew distribution of PaO2 before and after apnea testing. Informed consent was obtained from the kinfolk of all participants and all of the procedures were done in accordance with national and international laws and policies. Results Hemodynamics and oxygenarion were stable in all patients during MAT, and none regained spontaneous respiration. About 89.4% of tests were completed within 4 minutes, and 10.6% within 8 minutes. The mean value of Pa CO2 rise was (23.1 ±4.8), and the average rate of PaCO2 increase was 5.3 mmHg per minute. Conclusions Modified apnea test can be done safely for brain death evaluation and is a useful supplement to the common apnea test.