Albuterol delivery by metered-dose inhaler in a pediatric high-frequency oscillatory ventilation model

OBJECTIVES: To assess albuterol delivery by metered-dose inhaler (MDI) in a pediatric lung model ventilated by high-frequency oscillatory ventilation (HFOV). The percentage albuterol dose lost in the circuit's expiratory limb and the effects of operating frequency, inspiratory time, and use of a spacer were also determined. DESIGN: Prospective in vitro laboratory study. SETTING: Research laboratory. INTERVENTIONS: A model consisting of a HFOV and circuit, 4.5-mm endotracheal tube, and lung simulator was assembled. Ventilator settings were the following: humidified FIO2 of 1.0; mean airway pressure of 28 cm H2O; operating frequency of 10 Hz; pressure amplitude of 55 cm H2O; bias gas flow to maintain mean airway pressure; 30% inspiratory time; and temperature of 35 degrees C (95 degrees F). Lung simulator compliance and resistance values were consistent with pediatric patients with pulmonary disease. A total of ten MDI canisters were used to administer 2000 microg of albuterol with a spacer. Circuit filters placed proximal to the lung simulator and in the circuit's expiratory limb collected albuterol exiting the endotracheal tube and any albuterol lost, respectively. Filters were rinsed with water and albuterol concentrations determined by high performance liquid chromatography. Albuterol administration was repeated at operating frequencies of 5 and 15 Hz, inspiratory times of 40% and 50%, and with an actuator instead of a spacer. Each test condition was repeated ten times. Analysis of variance or Student's t-test was used to determine significant differences in albuterol delivered or lost among the operating frequencies and inspiratory times, and between the spacer and actuator. MEASUREMENTS AND MAIN RESULTS: Albuterol delivery to the lung simulator was <1% of the administered dose regardless of the operating frequency, inspiratory time, or use of a spacer or actuator. Albuterol lost in the expiratory limb ranged from 3.28% to 14.89% of the administered dose. CONCLUSIONS: These in vitro results suggest albuterol delivery by MDI in a pediatric model of HFOV is negligible, regardless of the operating frequency, inspiratory time, or use of a spacer or actuator.     

Hemolytic warm IgM autoagglutinins in autoimmune hemolytic anemia

The authors report a patient with fulminant autoimmune hemolytic anemia due to a rare warm IgM autoagglutinin more reactive at 37 degrees C than at lower temperatures and secondary to systemic lupus erythematosis. The patient's clinical course and the serologic and immunochemical characteristics of the antibody are described, including the possibility that transfusions of small amounts of incompatible red cells may have contributed to the hemolysis. The consequences of using the initial serologic test results as the basis for therapy are discussed.     

经冠状动脉移植自体骨髓单个核细胞和间充质干细胞对急性心肌梗死模型心功能的改善

目的:为保护濒死心肌提供机会窗口,对比观察经冠脉移植自体骨髓单个核细胞或间充质干细胞后,实验性急性心肌梗死动物心功能变化及心肌组织核转录因子кB、心肌细胞凋亡情况。方法:实验于2005-03/2006-11在河北省人民医院实验中心完成。选用24只雄性冀中白猪,随机数字表法分为4组:正常对照组、模型组、单个核细胞组、间充质干细胞组,6只/组。①24只猪均以盐酸氯胺酮200mg臀部肌肉注射麻醉后,分别于各自右侧股骨抽取骨髓20mL,采用Fercoll法分离获得骨髓单个核细胞,加入胶体金溶液,培养12～16h待用。分离过程中取出含有骨髓单个核细胞成分的细胞层,常规培养传代,每3d换液1次,贴壁生长细胞即为骨髓间充质干细胞,加入胶体金溶液,培养24h待用。②除正常对照组外,其余各组均经导管球囊封闭第一对角支以远的前降支,复制猪急性心肌梗死模型。单个核细胞组、间充质干细胞组均于造模后立即开通前降支,分别经球囊注入预先分离的骨髓单个核细胞6×108个、间充质干细胞6×108个。模型组造模后于梗死1h开通前降支,经球囊注入磷酸盐缓冲液10mL。③各组分别于术前及术后4周经心脏超声检测心功能,取材行病理学检查、心肌组织核转录因子кB的免疫组织化学检测及心肌细胞凋亡检测。结果:24只雄性白猪均进入结果分析。①心功能变化:术前各组左心室收缩末内径、左心室舒张末内径、左心室射血分数、短轴缩短率基本相似。移植术后4周,正常对照组、单个核细胞组、间充质干细胞组左心室舒张末内径均明显低于模型组(F=4.68,P=0.01),左心室射血分数及短轴缩短率均明显高于模型组(F=5.14,P=0.01;F=3.32,P=0.04),各组左心室收缩末内径差异无显著性意义(F=1.64,P=0.21)。②心肌组织病理学改变:电镜下单个核细胞组、间充质干细胞组在梗死边缘区可见有胶体金颗粒的不成熟的心肌细胞,胞质中散在肌丝结构,肌丝排列紊乱不规则。③心肌组织核转录因子кB阳性率表达:与模型组比较,单个核细胞组、间充质干细胞组的梗死边缘区核转录因子кB阳性率明显降低(F=25.59,P=0.0001);正常心肌区核转录因子кB阳性率亦明显降低(F=18.20,P=0.0001)。④心肌细胞凋亡检测结果:与模型组比较,单个核细胞组、间充质干细胞组在心肌梗死区细胞凋亡率均明显降低(F=6.63,P=0.0027),梗死边缘区细胞凋亡率亦明显降低(F=36.07,P=0.0001)。正常心肌区单个核细胞组细胞凋亡率与模型组基本相似(F=9.69,P=0.004),但间充质干细胞组有所降低。⑤心功能与心肌细胞凋亡及心肌组织NF-кB的相关性:急性心肌梗死4周时,左心室射血分数与心肌细胞凋亡、心肌组织核转录因子кB均呈负相关(r=0.613,P=0.001;r=-0.437,P=0.033)。心肌细胞凋亡与心肌组织核转录因子кB呈正相关(r=0.672,P=0.002)。结论:经冠脉移植骨髓单个核细胞和间充质干细胞均可改善实验性急性心肌梗死动物的心功能,与梗死边缘区核转录因子кB表达降低及心肌细胞凋亡减少有关。骨髓单个核细胞移植的促血管增生作用优于间充质干细胞移植。     

Effects of chronic morphine administration on the reproductive system of the male rat.

The effects of chronic morphine administration on a variety of rat organs were examined. Only the prostates and seminal vesicles were affected by a 3-day period of morphine pellet implantation. In these organs, particularly the seminal vesicles, morphine produced a marked decrease in both the wet and dry tissue weight and a reduction in their secretory activity. This apparent morphine-induced atrophy of these important accessory sex organs was not due to a change in the nutritional status of the animals but rather appeared to be associated with a pronounced (87 percent) reduction in the serum testosterone levels of morphine-treated rats when compared to control levels. The effect of morphine on the secondary sex organs was reversed by withdrawing the animals from morphine administration for a period of 7 days. These data suggest that the role of physiological and endocrinological factors in the narcotic addict's sexual difficulties be examined.     

Application of biosafety principles in blood establishments

In light of increasing public and employee concern over potential infectious hazards associated with blood and other body fluids, several government agencies (the Food and Drug Administration, the Centers for Disease Control, the Occupational Safety and Health Administration, the Environmental Protection Agency, the Health Care Financing Administration and the National Heart, Lung and Blood Institute) cosponsored a Biosafety Workshop in April 1988. The objective of the workshop was to identify appropriate biosafety practices and standard control procedures to protect workers involved in the collection, storage, and transportation of human blood donations with the least possible disruption of the nation's blood supply. Speakers focused on human immunodeficiency virus (HIV) and hepatitis B virus (HBV); however, the safety principles discussed were considered equally applicable to other known (e.g., non-A, non-B hepatitis and human T-lymphotropic virus type I (HTLV-1) blood-transmitted infections. The resulting consensus included the need for blood establishments to develop and apply thoughtful biosafety programs to address staff training, accident prevention, HBV vaccination, handling spills, managing contaminated waste and transporting blood specimens. There was lack of agreement, however, on the usefulness of gloves during the phlebotomy of healthy blood donors.     

Hyperscanning: simultaneous fMRI during linked social interactions

"Plain question and plain answer make the shortest road out of most perplexities." Mark Twain-Life on the Mississippi. A new methodology for the measurement of the neural substrates of human social interaction is described. This technology, termed "Hyperscan," embodies both the hardware and the software necessary to link magnetic resonance scanners through the internet. Hyperscanning allows for the performance of human behavioral experiments in which participants can interact with each other while functional MRI is acquired in synchrony with the behavioral interactions. Data are presented from a simple game of deception between pairs of subjects. Because people may interact both asymmetrically and asynchronously, both the design and the analysis must accommodate this added complexity. Several potential approaches are described.     

Risk indicators and psychopathology in traumatised children and adolescents with a history of sexual abuse

PURPOSE: Childhood sexual abuse (CSA) is widespread amongst South African (SA) children, yet data on risk factors and psychiatric consequences are limited and mixed. METHODS: Traumatised children and adolescents referred to our Youth Stress Clinic were interviewed to obtain demographic, sexual abuse, lifetime trauma and psychiatric histories. RESULTS: Data for 94 participants (59 female, 35 male; mean age 14.25 [8.25-19] years) exposed to at least one lifetime trauma were analysed. Sexual abuse was reported in 53% of participants (42.56% females, 10.63% males) with 64% of violations committed by perpetrators known to them. Multinomial logistic regression analysis revealed female gender (P=0.002) and single-parent families (P=0.01) to be significant predictors of CSA (62.5%). CSA did not predict exposure to other traumas. Sexually abused children had significantly higher physical and emotional abuse subscale scores and total CTQ scores than non-abused children. Depression (33%, X(2)=10.89, P=0.001) and PTSD (63.8%, X(2)=4.79, P=0.034) were the most prevalent psychological consequences of trauma and both were significantly associated with CSA. CONCLUSIONS: High rates of CSA predicted high rates of PTSD in this traumatised sample. Associations we found appear consistent with international studies of CSA and, should be used to focus future social awareness, prevention and treatment strategies in developing countries.     

Predictors and management of post-banding ulcer bleeding in cirrhosis: A systematic review and meta-analysis

Background and Aims

Post-banding ulcer bleeding (PBUB) is an understudied complication of oesophageal varices endoscopic band ligation (EBL). This systematic review with meta-analysis aimed at: (a) evaluating the incidence of PBUB in patients with cirrhosis treated with EBL in primary or secondary prophylaxis or urgent treatment for acute variceal bleeding and (b) identifying predictors of PBUB.

Methods

We conducted a systematic review of articles in English published in 2006–2022 using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Searches were made in eight databases including Embase, PubMed and Cochrane Library. Random-effects meta-analysis was used to determine the incidence, mean interval and predictors of PBUB.

Results

Eighteen studies (9034 patients) were included. The incidence of PBUB was 5.5% (95% CI 4.3–7.1). The mean time for it to occur was 11 days (95% CI 9.94–11.97). Model for End-stage Liver Disease (MELD) score (OR 1.162, 95% CI 1.047–1.291) and EBL done in emergency setting (OR 4.902, 95% CI 2.99–8.05) independently predicted post-ligation ulcer bleeding. Treatment included drugs, endoscopic procedures and transjugular intrahepatic portosystemic shunt. Refractory bleeding was treated with self-expandable metallic stents or balloon tamponade. Mortality was on average 22.3% (95% CI 14.1–33.6).

Conclusions

Patients with high MELD score and receiving EBL in an emergency setting are more prone to develop PBUB. Prognosis is still poor and the best therapeutic strategy to address remains to be ascertained.     

Timing of antibiotics in febrile children meeting sepsis criteria at a paediatric emergency department

Objective

Delay in antibiotic administration in paediatric sepsis is associated with increased mortality and prolonged organ dysfunction. This pre-intervention study evaluated performance in paediatric sepsis management.

Methods

Retrospective cohort study of febrile children admitted through the ED at The Children's Hospital at Westmead, Sydney, between 1 May and 31 July 2017. Participants were children aged 29 days to 60 months excluding children with simple febrile seizures, neonates and children who had received intravenous antibiotics elsewhere. We assessed the timing of antibiotic administration in children meeting local sepsis guidelines. We conducted a survey of clinicians in ED in 2018 to describe contributing factors.

Results

There were 160 febrile children admitted and 144 presentations were included in the analysis. Male 53% (n = 76); median age 20.1 months (interquartile range [IQR] 3.9–37 months). Thirty-seven (26%) febrile children met local sepsis criteria. The median time from triage to first dose of intravenous antibiotic was 109 min (IQR 62–183 min). Delay (>60 min) occurred in 26 (76%) children. Reported reasons contributing to delay included high patient load, long waiting times, difficult intravenous access, delayed prescribing, inadequate staffing and difficulty distinguishing between a viral infection and serious bacterial infection.

Conclusion

There was frequent delay in administering antibiotics in children meeting local sepsis criteria, more commonly in young infants. Reasons contributing to delay were specific to young children along with departmental factors that will require addressing through targeted quality improvement interventions.