目的 研究煤工尘肺(coal worker's pneumoconiosis, CWP)患者电子计算机断层扫描(computed tomograghy, CT)的影像学表现。方法 选取2017年10月—2020年10月我院CWP患者102例,均行CT检查、X线胸片检查,比较CT检查、X线胸片检查影像学征象、小阴影形态、大阴影影像学表现,并对比CT检查、X线胸片检查并发症情况(灶周气肿、胸膜改变、淋巴结肿大、钙化)。结果 CT检查、X线胸片检查大阴影、肺内钙化影、肺大疱、空洞检出率比较,差异无统计学意义(P＞0.05);CT检查小阴影检出率82.03%高于X线胸片检查73.20%(P＜0.05);CWP患者小阴影主要形态为q/q,且CT检查q/q比例82.67%高于X线胸片检查72.77%(P＜0.05);CT检查灶周气肿31.37%、胸膜改变21.57%、淋巴结肿大15.69%、钙化18.63%, 高于X线胸片检查18.63%、10.78%、6.86%、8.82%(P＜0.05)。结论 CT检查CWP患者影像学征象、并发症检出率均高于X线胸片检查,且小阴影以q/q为主,对大阴影表现明显,有助于病情早期诊断及治疗方案的制定。

Objective To study the imaging features of computed tomograghy (CT) scanning in coal worker's pneumoconiosis (CWP). Methods A total of 102 CWP patients in our hospital from October 2017 to October 2020 were selected. CT examination and X-ray chest examination were performed to compare the imaging features, small shadow shape and large shadow imaging manifestations, and compared the complications of CT examination and X-ray chest examination (focal emphysema, pleura change, lymph node enlargement and calcification). Results There was no statistical difference in the detection rates of large shadow, calcification shadow, pulmonary bulla and cavity in CT and X-ray chest examination (P>0.05); the detection rate of small shadow in CT was 82.03%, which was higher than that of X-ray chest examination (73.20%, P<0.05); the main shape of small shadow in CWP patients was q/q, and the q/q ratio of CT examination was 82.67%, higher than that of X-ray chest examination (72.77%, P<0.05); the detection rates of the focal emphysema by CT examination was 31.37%, the changes of pleura were 21.57%, lymph node enlargement was 15.69%, calcification was 18.63%, which were higher than those of X-ray chest examination (18.63%, 10.78%, 6.86%, 8.82%, P<0.05). Conclusion The detection rate of imaging signs and complications in CWP patients by CT was higher than that of X-ray, and the small shadow was mainly q/q, and CT examination was obvious for detecting large shadow, which was helpful for the early diagnosis and treatment of the disease.

目的 本文旨在研究穿心莲内酯对慢性阻塞性肺疾病急性加重期(acute exacerbation of chronic obstructive pulmonary disease,AECOPD)患者血清学中的炎症反应因子及肺部功能改变的影响。方法 从我院已出院的患者中挑选2017年6月—2018年6月期间收治的AECOPD患者共80例,其中给予哌拉西林舒巴坦抗感染和雾化吸入布地奈德及复方异丙托溴铵治疗的患者为对照组,对照组的治疗方法基础上给予喜炎平注射液的患者为观察组,各40例。对2组患者接受治疗前后血清学中的基质金属蛋白酶-9 (matrix metalloproteinase-9, MMP-9)、降钙素原 (procalcitonin, PCT)、白介素-6 (interleukin-6, IL-6) 水平和肺功能指标等方面进行比较。结果 2组治疗前血清学MMP-9、PCT、IL-6和肺功能指标第1秒用力呼气容积(forced expiratory volume in one second, FEV1)、用力肺活量(forced vital capacity, FVC)、一秒率(FEV1/FVC)无差异(P＞0.05)。观察组经过治疗后MMP-9为(1995.13±347.281)pg/mL、IL-6为(7.98±3.23)pg/mL,低于对照组的(2159.30±367.477)pg/mL、(10.03±5.45)pg/mL(P＜0.05);观察组治疗后的PCT、FEV1、FVC和FEV1/FVC与对照组相比差异无统计学意义 (P＞0.05)。结论 穿心莲内酯在AECOPD患者中可以减少血清学中炎症因子,值得在临床中推广。

Objective To investigate the effect of andrographolide on levels of serum inflammatory factors and pulmonary function in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods Eighty patients with AECOPD who were treated in our hospital from June 2017 to June 2018 were selected. Forty patients in the control group were given anti-infection treatment with piperacillin and sulbactam and aerosol inhalation with compound ipratropium bromide and budesonide, while other 40 patients in study group were given andrographolide additionally. The levels of serum matrix metalloproteinase-9 (MMP-9), procalcitonin (PCT), interleukin-6 (IL-6) and the pulmonary function indexes of patients in the two groups were observed and compared before and after treatment. Results There were no statistically significant differences in the serum levels of MMP-9, PCT and IL-6 and the pulmonary function indexes forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and FEV1/FVC of the two groups before treatment (P>0.05). After treatment, in the study group, the MMP-9 and IL-6 levels in serum were (1995.13±347.281)pg/mL and (7.98±3.23)pg/mL respectively, which were significantly lower than that in the control group [(2159.30±367.477) pg/mL and (10.03±5.45) pg/mL (P＜0.05)].Compared with the control group, differences in the PCT, FEV1, FVC and FEV1/FVC in the study group were not statistically significant (P>0.05). Conclusion Andrographolide had significant clinical effect on the treatment of AECOPD, which could reduce the levels of serum inflammatory factors and it is worthy of clinical application.

目的 分析CT肺动脉栓塞指数(PAOI)与急性肺栓塞(APE)患者右心功能与预后的相关性。方法 以收治的86例疑似患者为研究对象,均行CT肺动脉成像(CTPA)检查,共60例APE患者,依据患者病情严重程度分为轻度、中度与重度,而无APE患者26例(对照组),分析左右心室最大短轴内径(RVd/LVd)、左右心室最大截面积比(RVA/LVA)、右心室短轴最大直径(RVMSA)、左心室短轴最大内径(LVMSA)、主肺动脉直径(MPAd)、上腔静脉直径(SVCd)、奇静脉直径(AZd)、动脉血氧分压(PaO₂)、动脉血二氧化碳分压(PaCO₂)以及动脉血氧饱和度(SaO₂)与PAOI的相关性,并分析患者预后情况。结果 经比较,中、重度患者RVd/LVd、RVA/LVA、RVMSA、MPAd与AZd水平高于轻度患者,而LVMSA低于轻度患者(P<0.05);且重度患者RVd/LVd、RVMSA水平高于中度,而RVA/LVA、LVMSA、MPAd与AZd水平比较无意义(P>0.05);3组SVCd水平比较P>0.05,其他参数指标比较差异明显(P<0.05);APE患者的PaO₂、PaCO₂以及SaO₂水平随着患者病情的加重呈现出逐渐下降趋势,且3组患者的PaO₂对比差异有统计学意义(P<0.05);PaO₂、PaCO₂和SaO₂与PAOI均呈负相关,且仅有PaO₂的差异存在统计学意义(P<0.05);POAI对APE患者的死亡有着一定的预测价值(P<0.05),最佳切点值58.91%,敏感度为85.29%,特异度为89.93%,其他数据未见明显诊断预测价值(P>0.05)。故RVd/LVd、RVA/LVA、RVMSA、MPAd与AZd水平与PAOI成正相关,而LVMSA水平与PAOI成负相关,与SCVd无关。结论 PAOI与APE患者的右心功能各参数以及动脉血气各参数均有密切关联性,可将其作为患者预后评估的有效指标。

目的 分析胞内分枝杆菌肺病与堪萨斯分枝杆菌肺病的胸部CT影像特征差异。方法 收集天津市海河医院胞内分枝杆菌肺病(A组)和堪萨斯分枝杆菌肺病(B组)各70例胸部CT图像,分析比较两组CT特征差异。结果 2组在性别、年龄上差异有统计学意义,A组小叶中心结节及树芽征、结节、厚壁空洞、支气管扩张比例均大于B组,A组薄壁空洞占比小于B组。A组分布在右肺上、下叶的空洞多于B组,右肺中叶支气管扩张少于B组。A组分布在右肺中叶、下叶及左肺上叶舌段、下叶的支气管扩张占比较B组多。结论 胞内分枝杆菌肺病病灶较堪萨斯分枝杆菌肺病多,以支气管扩张尤为明显,堪萨斯分枝杆菌肺病薄壁空洞较为显著。

Objective To compare and analyze CT imaging features differences between Mycobacterium intracellulare pulmonary disease and Mycobacterium kansasii pulmonary disease. Methods The CT images of 70 cases with Mycobacterium intracellulare lung disease(group A) and 70 cases with Mycobacterium kansasii lung disease(group B)were collected. The CT features of the two groups were compared by statistical analysis. Results The differences of gender and age between the two groups were statistically significant. The central nodule and tree-in-bud, nodule, thick wall cavity and bronchiectasis incidences in group A were more than those in group B. The thin wall cavity incidence in group A was less than those in group B. The number of cavities in the upper and lower lobe of the right lung in group A was bigger than group B,and the proportion of bronchiectasis in the middle lobe of the right lung in group A was less than those of group B. The bronchiectasis in the middle, lower lobe of right lung and upper lobe lingual segment and lower lobe of left lung in group A were more than those in group B. Conclusion The pulmonary lesion number of Mycobacterium intracellulare was bigger than that of Mycobacterium kansasii, especially bronchiectasis. The thin wall cavity of Mycobacterium kansasii pulmonary disease is more obvious.

目的 探讨老年吸入性肺炎的危险因素,建立风险预测模型,以期降低老年吸入性肺炎的发病率。方法 选取2017年8月28日—2020年 10月30日广州市第一人民医院老年病科住院治疗的老年肺炎患者205例,按照是否发生吸入性肺炎分为吸入性肺炎组和非吸入性肺炎组,对比2组患者的各项指标,分析老年吸入性肺炎的危险因素,建立风险预测模型,采用ROC曲线对模型进行预测效果检验。结果 多因素Logistic回归分析结果显示,脑梗塞、帕金森、留置胃管、长期卧床为老年吸入性肺炎的危险因素(P<0.05)。模型公式为Logit(P)=-2.952+1.221X₂+2.417X₃+2.388X₈+1.683X₁₀。该模型ROC曲线下面积为0.894。结论 本研究中的模型预测效果良好,可为医护人员预测老年患者发生吸入性肺炎的概率,及时采取相应的预见性护理及干预性治疗。

Objective To explore the risk factors of aspiration pneumonia in the elderly and establish the risk prediction model, in order to reduce the incidence of aspiration pneumonia in the elderly. Methods A total of 205 elderly patients with pneumonia who were hospitalized in the department of geriatrics, Guangzhou First People's Hospital from August 28, 2017 to October 30, 2020, were divided into aspiration pneumonia group and non-aspiration pneumonia group according to whether aspiration pneumonia occurred. The indicators of the two groups of patients were compared, the risk factors of aspiration pneumonia in the elderly were analyzed, the risk prediction model was established, and the prediction effect of the model was tested by receiver operating characteristic curve. Results Multivariate Logistic regression analysis showed that cerebral infarction, Parkinson's disease, indwelling nasogastric tube, and being bedridden were risk factors for aspiration pneumonia in elderly patients (P<0.05). The model formula was Logit (P)=-2.952+1.221X₂+2.417X₃+2.388X₈+1.683X₁₀. The area under receiver operating characteristic curve of this model was 0.894. Conclusion The prediction effect of the model in this study was good, which could predict the probability of aspiration pneumonia in elderly patients for medical staff, and to timely take the corresponding predictive care and interventional treatment.

目的 为初步评估在无创辅助通气基础上进行雾化肺表面活性物质(AS)治疗呼吸窘迫综合征(RDS)早产儿的安全性及效果,开展了此项临床研究。方法 2019年7月—2020年6月,经监护人知情同意,符合入选标准的RDS早产儿,入院后在经鼻间歇正压通气(NIPPV)基础上,通过振动筛网雾化器系统给予100 mg/kg注射用牛肺表面活性剂,雾化完毕继续无创辅助通气。详细观察及记录患儿在雾化初期的生命体征及血气分析结果,记录在雾化治疗期间不良反应发生情况以及患儿病情转归情况。结果 20例患儿参与研究,1例出生后26天死亡,其余均存活出院。5例在AS治疗后3天内无创辅助通气失败。和雾化前比较,AS治疗后1小时患儿血气分析主要指标均改善,血氧饱和度上升,心率下降(P＜0.05),但血压及呼吸机参数无明显变化(P＞0.05)。在雾化过程中,所有患儿无明显不良反应发生。结论 此项临床研究初步显示AS联合无创辅助通气治疗早产儿RDS是安全可行的,但尚需进一步临床研究评估其效果。

Objective To evaluate the safety and efficacy of non-invasive ventilation with aerosolized surfactant (AS) in the treatment of premature infants with respiratory distress syndrome (RDS). Methods From July 2019 to June 2020, in this unblinded Phase I study, the premature infants with RDS who met the criteria with the informed consent of their guardians were enrolled. They were treated with nasal intermittent positive pressure ventilation (NIPPV) and received one dose (100 mg/kg) of aerosolized surfactant by vibrating mesh system (Aeroneb Solo) after hospitalization. The vital signs, adverse reactions and blood gas during areosolizing were recorded and prognosis of them also recorded in detail. Results Twenty infants were enrolled, nineteen completed the study, one died in 26 days. Five infants still required endotracheal intubation and mechanical ventilation after AS treatment. One hour after AS treatment, infants' oxygen saturation and indicators of pulse oximetry improved (P＜0.05), and heart rate decreased (P＜0.05) , but blood pressure and parameters of ventilator had no change (P＞0.05). Infants all tolerated the aerosol treatment well. No other significant adverse events were identified. Conclusion We have demonstrated the feasibility and safety of AS treatment in preterm infants with RDS receiving non-invasive respiratory support. The treatment was well tolerated by infants and clinical caregivers , but still need further study.

目的 使用TCGA数据库,探索DNA甲基化位点对肺腺癌的预后影响。方法 使用TCGA数据库,获取肺腺癌病人癌和癌旁组织甲基化表达数据、基因表达数据及临床数据;将人群分为探索组和验证组,使用LASSO在探索人群中筛选对肺腺癌预后有影响的甲基化位点;受试者工作特征曲线用于评估甲基化位点预测效果,并进一步在验证人群中验证。结果 在TCGA数据库中筛选出158个癌和癌旁组织差异表达且与所在基因mRNA表达显著相关的甲基化位点,经LASSO回归分析,cg19378330与肺腺癌预后相关。甲基化位点水平高于中位数的患者,归入高风险组,甲基化位点水平低于中位数的为低风险组。结果发现与低风险组相比,高风险组的死亡风险比低风险组增加了38%(OR=1.38,95% CI=1.16～2.69)。在探索阶段人群中其曲线下面积为0.80(95% CI=0.73～0.88),灵敏度为86.2%。验证人群中也表现出类似结果。结论 甲基化位点cg19378330与肺腺癌具有较显著的关联性,且可以对肺腺癌的风险进行有效的预测。

Objective Using the TCGA database to explore the prognostic effects of DNA methylation sites on lung adenocarcinoma. Methods TCGA database was used to collecting DNA methylation data, gene expression data and clinical data of lung adenocarcinoma patients. The population were divided into the exploratory group and the validation group. The LASSO regression analysis was used to screen the methylation sites associated with the prognosis of lung adenocarcinoma in the exploratory group. Receiver operating characteristic curve was used to evaluate the prediction effect of the model, and further verified in the validation population. Results A total of 158 methylation sites with differential expression and significant correlation with the mRNA expression of the corresponding gene were screened from the TCGA database. With LASSO regression analysis, the DNA methylation sites associated with prognosis of lung adenocarcinoma were cg19378330. Those patients with levels above the median methylation site were assigned to the high-risk group, while those with levels below the median methylation site were assigned to the low-risk group. Patients' death risk in the high-risk group were 38% higher than those in the low-risk group (OR=1.38, 95%CI=1.16-2.69). The area under the curve was 0.80 (95%CI=0.73-0.88) and the sensitivity was 86.2% in the exploratory stage population.Similar results were seen in the validation population. Conclusions The DNA methylation site cg19378330 was significantly associated withthe prognosisof lung adenocarcinoma, and could effectively predict the risk of lung adenocarcinoma.

目的 对儿童重症肺炎支气管肺泡灌洗液(BALF)进行病原学分析及疾病预后的分析。方法 本研究选取2019年3月—2020年12月在我院儿科住院并进行肺泡灌洗治疗的40例重症肺炎患儿作为研究对象。通过对这些患儿在感染急性期肺泡灌洗液中的细菌、真菌、肺炎支原体等进行病原学检查以及T 淋巴细胞亚群的检测,了解台山地区儿童重症肺炎病原体情况及耐药性、T淋巴细胞亚群与疾病严重程度、预后评估的关系。结果 BALF病原学检测结果分析中,肺炎支原体27例,肺炎支原体+肺炎链球菌5例,肺炎支原体+中间葡萄球菌2例,肺炎支原体+铅黄肠球菌1例,肺炎支原体+嗜麦芽假单胞菌2例,病原菌阴性3例;本组病例血清T细胞亚群检测结果显示:大部分病例CD3⁺、CD4⁺、CD8⁺及CD4⁺/CD8⁺水平有不同程度的下降。其中CD3⁺水平下降的有6例,CD4⁺水平下降的有16例,CD8+水平下降的有17例,CD4⁺、CD8⁺水平同时下降的有14例,CD3⁺、CD4⁺、CD8⁺水平同时下降的有4例;BALF细胞总数(3673.1±377.9)×10⁶ /L,巨噬细胞比例(23.6±17.6)%,淋巴细胞(22.1±16.2)%,中性粒细胞(46.5±24.8)%。结论 病原学分析儿童重症肺炎BALF的主要病原菌为肺炎支原体,血清T细胞亚群检测大多表现为CD4⁺、CD8⁺水平下降。

Objective To analyze the etiology of bronchoalveolar lavage fluid and prognosis of children with severe pneumonia. Methods In this study, 40 children with severe pneumonia who were hospitalized in the pediatrics department of our hospital and underwent alveolar lavage treatment from March 2019 to December 2020 were selected as the research objects. Through the detection of pathogens such as bacteria, fungi, Mycoplasma pneumoniae and T lymphocyte subsets of these children in the acute phase of infection, we can understand the pathogens and drug resistance of children with severe pneumonia in Taishan area and the relationship among drug resistance, T lymphocyte subsets and disease severity and prognosis assessment. Results In the analysis of the BALF pathogenic test results, there were 27 cases with Mycoplasma pneumoniae, 5 cases with Mycoplasma pneumoniae+Streptococcus pneumoniae, 2 cases with Mycoplasma pneumoniae+Staphylococcus intermedius, 1 case with Mycoplasma pneumoniae+Enterococcus casseliflavus, 2 cases with Mycoplasma pneumoniae+Pseudomonas maltophilia and 3 cases were pathogenic bacteria negative. The test results of serum T cell subsets of these cases showed that most of the cases had different degrees of decline in the levels of CD3⁺, CD4⁺, CD8⁺ and CD4⁺/CD8⁺. Among them, CD3⁺ levels decreased in 6 cases, CD4⁺ levels decreased in 16 cases, CD8⁺ levels decreased in 17 cases, CD4⁺ and CD8⁺ levels decreased in 14 cases, and CD3⁺, CD4⁺, and CD8⁺ levels decreased in 4 cases; total cell number of BALF was (3 673.1±377.9)×10⁶/L, the proportion of macrophages was (23.6±17.6)%, lymphocytes had (22.1±16.2)%, and neutrophils had (46.5±24.8)%. Conclusions Pathogenic analysis showed that the main pathogen of BALF in children with severe pneumonia is Mycoplasma pneumoniae, and the detection of serum T cell subsets mostly showed a decrease in CD4⁺ and CD8⁺ levels.

目的 探究血清C反应蛋白与白蛋白比值(CRP/ALB)、中性粒细胞与淋巴细胞比值(NLR)、血糖不稳定指数(GLI)水平对重症肺炎患者预后的预测价值。方法 将我院2020年1月—2021年5月收治的126例重症肺炎患者作为研究对象,根据入院治疗28 d的预后情况,分为存活组(93例)和死亡组(33例)。对比2组患者的一般资料,采用多因素Logistic分析重症肺炎患者高危因素,应用ROC曲线评估血清CRP/ALB、NLR、GLI水平对重症肺炎患者预后的预测价值。结果 2组患者一般资料对比,NEU、CRP、APACHEⅡ、CRP/ALB、NLR、GLI水平差异有统计学意义(P<0.05);多因素Logistic回归分析显示APACHEⅡ评分、血清CRP/ALB、NLR、GLI水平是重症肺炎患者死亡的危险因素;ROC曲线分析结果显示,CRP/ALB、NLR、GLI曲线下面积分别为0.837,0.826,0.837。结论 CRP/ALB、NLR、GLI水平对重症肺炎患者预后均具有较高的预测价值,其中以CRP/ALB的预测价值最佳。

Objective To explore the prognostic predictive value of serum CRP/ALB, NLR and GLI in patients with severe pneumonia. Methods A total of 126 patients with severe pneumonia treated in our hospital from January 2020 to May 2021 were divided into survival group (93 cases) and death group (33 cases) according to the prognosis of 28 days of hospitalization. The general data of the two groups were compared, the high-risk factors of patients with severe pneumonia were analyzed by multivariate logistic, and the predictive value of serum CRP/ALB, NLR and GLI levels on the prognosis of patients with severe pneumonia was evaluated by ROC curve. Results There were significant differences in the levels of NEU, CRP, APACHE Ⅱ, CRP/ALB, NLR and GLI between the two groups (P<0.05); multivariate logistic regression analysis showed that APACHE Ⅱ score, serum CRP/ALB, NLR and GLI were the risk factors of death in patients with severe pneumonia; ROC curve analysis showed that the areas under CRP/ALB, NLR and GLI curves were 0.837, 0.826 and 0.837 respectively. Conclusions The levels of CRP/ALB, NLR and GLI had high predictive value in the prognosis of patients with severe pneumonia, among which CRP/ALB had the best predictive value.

目的 探讨慢性阻塞性肺疾病(COPD)并发低氧血症患者抢救中使用小剂量肾上腺素及布地奈德的价值。方法 纳入50例COPD并发低氧血症患者研究(2018年4月—2021年4月),按双盲法分为对照组(n=25,采用布地奈德雾化吸入治疗)、观察组(n=25,在对照组基础上采用肾上腺素治疗),统计2组抢救成功率、临床指标、预后效果。结果 (1)抢救成功率:观察组(96.00%)高于对照组(76.00%),组间对比P<0.05。(2)临床指标:观察组PaCO₂(43.29±4.92 mmHg)低于对照组,PaO₂(86.77±8.25 mmHg)、SpO₂(92.14±2.82%)、pH(7.43±0.12)、FVC(2.41±0.28 L)、FEV1(1.72±0.72 L)、FEV1/FVC(70.95±8.22%)高于对照组,组间对比P<0.05。(3)预后效果:观察组气喘(3.22±1.08 d)、哮鸣音(5.21±1.11 d)消失时间及住院时间(9.61±2.24 d)短于对照组,组间对比P<0.05。结论 小剂量肾上腺素联合布地奈德在COPD并发低氧血症治疗中效果确切,可提高抢救成功率,亦可改善其肺功能及血气指标,值得临床参考。

Objective To explore the value of low dose epinephrine and budesonide aerosol inhalation in the rescue of patients with chronic obstructive pulmonary disease(COPD) complicated with hypoxemia. Methods Fifty patients with COPD complicated with hypoxemia(April 2018 to April 2021)were enrolled and divided into control group(n=25,treated with budesonide aerosol inhalation)and observation group(n=25,treated with epinephrine additionally)according to double-blind method.The rescue success rate,clinical indicators and prognosis of the two groups were statistically analyzed. Results (1)The success rate of rescue of the observation group(96.00%)was higher than that of the control group(76.00%,P<0.05). (2)Clinical indicators:PaCO₂(43.29 1±4.92 mmHg)in the observation group was lower than that of the control group,PaO₂(86.774±8.25 mmHg), SpO₂(92.14±2.82%), pH(7.43±0.12), FVC(2.41±0.28 L), FEV1 (1.72±0.72 L), FEV1/FVC (70.95±8.22%)were higher than that in the control group(P<0.05). (3)Prognosis effect:asthma duration in the observation group(3.22±1.08 d),wheezing disappeared time(5.211±1.11 d)and hospitalization time(9.611±2.24 d)were shorter than that of the control group(P<0.05). Conclusions Low dose epinephrine combined with budesonide in the treatment of COPD complicated with hypoxemia has definite effect, which can improve the success rate of rescue,also improve lung function and blood gas index. It is worthy of clinical reference.