Mycobacterium ulcerans-specific immune response after immunisation with bacillus Calmette-Guérin (BCG) vaccine

BackgroundBacillus Calmette–Guérin (BCG) vaccine provides partial protection against Buruli ulcer caused by Mycobacterium ulcerans in epidemiological studies. This study aimed to quantify M. ulcerans-specific immune responses induced by BCG immunisation.MethodsIntracellular cytokine analysis of in-vitro experiments done 10 weeks after BCG immunisation in 130 Australian infants randomised to one of three BCG vaccine strains given either at birth (BCG-Denmark, BCG-Japan, or BCG-Russia) or at two months of age (BCG-Denmark).ResultsProportions of polyfunctional CD4⁺ T-cells were higher in M. ulcerans-stimulated compared to unstimulated control samples. These proportions were not influenced by the vaccine strain or timing of the immunisation. The M. ulcerans-specific immune responses showed similar patterns to those observed in M. tuberculosis-stimulated samples, although they were of lower magnitude.ConclusionsOur data show that BCG immunisation induces M. ulcerans-specific immune responses in infants, likely explaining the cross-protective effect observed in epidemiological studies. (ACTRN12608000227392)     

Long-term persistent immunogenicity after successful standard and triple-dosed hepatitis B vaccine in hemodialysis patients: A 3-year follow-up study in China

BackgroundAlthough the efficacy of hepatitis B vaccines among hemodialysis patients has been documented, the long-term persistence of immunogenicity in this population remains largely unknown. We explored the long-term persistence of immunogenicity induced by different hepatitis B vaccine regimens in hemodialysis patients.MethodsIn initial study, we conducted a randomized, multicenter, double-blind, parallel-controlled trial among hemodialysis patients in 13 hospitals in Shanxi Province, China. A total of 352 hemodialysis patients were allocated to receive 3-dose 20 μg (IM20 group) and 3-dose 60 μg (IM60 group) recombinant hepatitis B vaccine at months 0, 1, and 6. Vaccine-induced immune responses were measured at month 7. In this study, the responders (anti-HBs ≥ 10 mIU/mL) were followed up at months 18, 24, 30, 36 and 42, respectively. We used the generalized log-rank test and generalized estimating equations (GEE) to analyze the long-term durability of responses and the kinetics of anti-HBs levels, respectively.ResultsA total of 284 patients were involved in the extended follow-up period. The duration of vaccine-induced response with 75% of patients maintained protective antibody were 12 months and 18 months in the IM20 group and IM60 group, respectively (P = 0.291). The long-term persistent immunogenicity induced by 3-dose 60 μg was more satisfactory than that by 3-dose 20 μg hepatitis B vaccine in patients with hemodialysis duration ≥ five years (P = 0.023). The peak anti-HBs levels in 100–1000 mIU/mL or ≥ 1000 mIU/mL were more likely to maintain long-term protective antibody compared to anti-HBs levels in 10–100 mIU/mL (P ＜ 0.05). The kinetic profile was similar between the two groups (P = 0.334).ConclusionHigh-dose 60 μg hepatitis B vaccine could lead a satisfactory long-term durability of immunogenicity among patients with hemodialysis duration of five years or more. Peak anti-HBs level after vaccination was associated with the long-term persistence of immunogenicity.     

电阻抗断层成像技术用于呼气末正压滴定的研究进展

适当的呼气末正压（PEEP）是保护性肺通气策略的重要组成部分,PEEP可以保持肺泡开放,减少肺萎陷伤。尽管个体化PEEP已被越来越多的临床医师认可,但最佳的PEEP滴定方法尚存争议。电阻抗断层成像（EIT）是一种无创、无辐射的成像技术,可在床边实时动态评估肺功能,将肺通气过程中的阻抗变化以动态图像呈现,能够反映PEEP调整前后肺内通气及气体分布变化,因此,EIT可用于滴定个体化PEEP。本文简要概括EIT的基本原理及监测指标,阐述临床应用EIT指导下的PEEP（PEEPEIT）滴定方法,旨在加强对EIT的优点和局限性的理解,为优化个体化PEEP的设置提供参考。     

Airway occlusion pressure (P0.1) — A useful predictor for the weaning outcome in patients with acute respiratory failure —

Twenty-five patients who required mechanical ventilatory support (MVS) after major surgery or severe burns were studied to determine whether airway occlusion pressure (P_0.1) is a clinically useful indicator to predict the success or failure of the weaning trial. A total of 33 weaning trials were attempted on these patients. Of the 33 trials, 24 were followed by successful weaning and 9 by failure. Although the success group, when compared with the failure group, had a lower respiratory rate (P 0.001), a lower minute ventilation (P 0.001), a higher maximal voluntary ventilation to minute ventilation ratio (P 0.01) and a higher forced vital capacity (P 0.05), no threshold values separated the success from the failure group. The alveolar-arterial P_{O 2} gradient, with an Fi _{O 2} of 1.0, in weaning success and failure showed no statistical difference. In contrast, all patients in the success group had a P_0.1 of less than 3.5cmH₂O and those in the failure group had a P_0.1 of greater than 3.5cmH₂O (P 0.001). We conclude that P_0.1 is a clinically superior indicator for discontinuing MVS in patients with acute respiratory failure.(Okamoto K, Sato T, Morioka T: Airway occlusion pressure (P_0.1)—A useful predictor for the weaning outcome in patients with acute respiratory failure—. J Anesth 4: 95–101, 1990)     

Evaluation of conventional weaning criteria in patients with acute respiratory failure

We evaluated the reliability of conventional weaning criteria from a ventilator during 33 weaning trials on 25 patients with acute respiratory failure (ARF). Of 13 criteria, a ratio of maximal voluntary ventilation to minute ventilation (MV) 2, a vital capacity 12ml·kg^–1, a spontaneous respiratory rate 25 breaths·min^–1, and a MV 10l·min^–1 appeared to be useful for predicting successful weaning outcome. However, even using those criteria, there were many falsely-negative cases. The alveolar-arterial P_{O 2} gradient 350mmHg at an Fi _{O 2} 1.0 was not useful as a predictor of weaning outcome. The present study demonstrates that conventional criteria are frequently inaccurate for predicting weaning outcomes and suggests that the use of some of these criteria may unnecessarily prolong the length of ventilator support. Since ventilation of most patients with poor oxygenation can be successfully discontinued by placing them on a continuous positive airway pressure system, these results suggest that the improvement of oxygenation is not an indispensable prerequisite for weaning from mechanical ventilators.(Okamoto K, Iwamasa H, Dogomori H, et al.: Evaluation of conventional weaning criteria in patients with acute respiratory failure. J Anesth 4: 213–218, 1990)     

Low-dose sufentanil and lidocaine supplementation of general anaesthesia

This randomized double-blind study compared the effects of: (1) saline infusion (C); (2) sufentanil alone (1.0 micrograms.kg-1) (S); and (3) low-dose sufentanil (0.5 micrograms.kg-1) in combination with lidocaine (1.5 mg.kg-1) (LS): on the cardiovascular responses to tracheal intubation and on postoperative ventilation as monitored by respiratory inductive plethysmography in day-care surgical procedures of approximately 60 min duration. Thirty healthy, unpremedicated patients were studied. Thiopentone requirements were reduced by 40 and 28 per cent in the S and LS groups respectively compared with control (P less than 0.001). Both treatments suppressed HR and BP responses (P less than 0.005) to intubation. Postoperatively, PaCO2 was elevated (P less than 0.05) in group S. Dose-related respiratory depression was observed. The incidence of postoperative apnoea was significantly higher in both S and LS groups than compared with control (P less than 0.05). However, only patients in group S showed higher apnoea index and mean apnoea duration over the initial 10-20 min after surgery compared with control (P less than 0.005). In addition, group S showed slower respiratory frequency and prolonged expiratory time (P less than 0.005). In conclusion, an induction dose of sufentanil (1 microgram.kg-1) used in balanced anaesthesia of less than 70 min duration was associated with significant respiratory depression, particularly during the initial 10-20 min after surgery, whereas low-dose sufentanil (0.5 micrograms.kg-1) with lidocaine (1.5 mg.kg-1) had minimal postoperative respiratory depression and comparable attenuation of pressor responses to intubation.     

穴位体表电刺激对术后PCEA的强化效应

目的　观察穴位体表电刺激对术后患者硬膜外自控镇痛（PCEA）效果、镇痛药用量、血清皮质醇浓度和不良反应的影响。方法　 选择经腹全宫切除术患者40例（ASAⅠ～Ⅱ级）,随机分成二组,每组20例。A组：于术后第4,8小时 Han's各刺激30 min,术后行PCEA。B组：单纯行术后PCEA（对照组）。术后随访镇痛效果、镇静评分、布氏舒适评分（BCS）,分段记录24 h镇痛药用量及总按压次数/实进次数（D1/D2）比值,血清皮质醇含量,肛门恢复排气时间和不良反应情况。结果　两组镇痛效果满意,A组BCS评分高于B组（P＜0.05）。A组镇痛药用量为（31.7±1.9）ml,与对照组（34.2±2.1）ml相比差异有显著性（P＜0.01）。血清皮质醇浓度两组均较术前下降,但A组术后8 h的下降幅度大于对照组。A组恢复肛门排气时间快于B组,而且恶心、呕吐与对照组相比有所减少。结论　术后患者硬膜外腔自控镇痛（PCEA）复合应用穴位体表电刺激,可增强镇痛效果,减少用药量,降低不良反应,是安全有效的复合镇痛方法。     

单肺通气时肺内分流与PETCO2的相关性研究

目的：研究单肺通气时PETCO2和Qs/Qt之间的关系。方法：选择28例择期开胸手术的患者分别于TLV 20min、OLV 5min、15min、30min、60min测动脉血和混合静脉血气并同时记录PETCO2,计算Qs/Qt,进行统计学处理。结果：OLV时不同时段PETCO2、PaCO2、Qs/Qt比TLV时增大(P＜0.05),TLV时PETCO2与Qs/Qt不相关(r=-0.0230,P=0.9077)。OLV时PETCO2与Qs/Qt相关(r=0.4739,P=0.00001),其直线回归方程为y=3.4862+0.0147x(y=PETCO2,x=Qs/Qt)。结论：OLV时PETCO2与Qs/Qt呈直线相关,PETCO2随Qs/Qt增加而增大。     

咯血并呼吸衰竭患者机械通气治疗初步观察

目的探索咯血并呼吸衰竭(COPD)患者机械通气治疗的效果。方法阐明了一例表皮葡萄球菌肺部感染的COPD患者产生大咯血并呼吸衰竭的原因及治疗经过,详细分析了治疗过程中的各种临床问题。结果表皮葡萄球菌肺部感染的COPD患者可以有大咯血的临床表现,该患者经抗感染、纤支镜止血、机械通气等积极治疗后得到康复出院。结论机械通气是治疗咯血并呼吸衰竭COPD患者的主要方法之一,咯血并不影响机械通气的治疗效果,机械通气对咯血的治疗也没有造成不良影响。