The effect of back-up rate during non-invasive ventilation in young patients with cystic fibrosis

Objective The aim of the study was to evaluate the effect of the back-up rate on respiratory effort during non-invasive mechanical ventilation.Design An in vitro study evaluated the inspiratory trigger in seven domiciliary ventilators. Then, a prospective, randomized, crossover trial compared the effect on respiratory effort of three different back-up rates during pressure support (PS) and assist-control/volume-targeted (AC/VT) ventilation.Setting A research unit and a tertiary referral pediatric center.Patients Ten patients with cystic fibrosis (CF).Interventions During the in vivo study, the back-up rate was progressively increased to the maximum that patients could tolerate (Fmax) and respiratory effort, as judged by pressure/time product of the diaphragm (PTPdi/min), was compared between the two ventilatory modes.Results Differences were observed between trigger pressure, trigger time delay, trigger pressure/time product and the slope between flow and pressure in the seven ventilators. PS and AC/VT ventilation were associated with a decrease in respiratory effort (PTPdi/min was 518±172, 271±119 and 291±138 cmH₂O . s^–1 . min^-1, for spontaneous breathing, PS and AC/VT ventilation, respectively, p=0.05). During the two modes, increasing the back-up rate to Fmax resulted in a greater reduction in PTPdi/min (p=0.001), which was more pronounced during AC/VT ventilation, due to the automatic adjustment of the inspiratory/expiratory time ratio.Conclusions Increasing the back-up rate during PS and AC/VT ventilation decreases respiratory effort in young patients with CF, but this effect was more marked with AC/VT ventilation.Electronic Supplementary Material Supplementary material is available in the online version of this article at This study was supported with grants from Vaincre la Mucoviscidose (VLM), the Comité National contre les Maladies Respiratoires (CNMR) and the Société de Pneumologie de Langue Française (SPLF).     

Should aminophylline be abandoned in the treatment of acute asthma in adults?

Intravenous aminophylline is widely used for the treatment of acute asthma and anecdotes about its apparent effectiveness abound. Early studies demonstrated that aminophylline is an inefficient bronchodilator compared with adrenergic agonists given by injection or inhalation. This paper presents the results of a review of randomized controlled trials examining the effect of adding aminophylline to standard modern therapy with a nebulized beta(2) agonist and systemic corticosteroids in acute asthma in adults. Six of the seven trials, comprising 343 patients, failed to demonstrate any beneficial effect of aminophylline. Furthermore, minor toxicity was common. There is presently no evidence to support the use of aminophylline in addition to standard therapy for acute asthma in adults.     

Lipoprotein and apoprotein levels in postmenopausal women during treatment with norethisterone

Lipoprotein and apolipoprotein levels were monitored in 21 postmenopausal women during 6 months' treatment with norethisterone. There was no significant change in low density lipoprotein (LDL) cholesterol but apoprotein B levels rose significantly (p less than 0.001) thus increasing the apoprotein:cholesterol ratio in LDL. High density lipoprotein (HDL) cholesterol levels decreased significantly (p less than 0.001) in the first two months and did not change significantly thereafter. The HDL2 subfraction was reduced to a greater extent than the HDL3 subfraction. Apoprotein AI and AII levels were both reduced as was the apoprotein AI:AII ratio. The ratios of apoproteins AI and AII to HDL cholesterol were increased. We conclude that norethisterone has an adverse effect on the important risk factors for cardiovascular disease.     

膈肌疲劳对呼吸中枢驱动的影响

膈肌是主要的呼吸肌，我们设想膈肌疲劳可能会导致呼吸中枢驱动增高以维持正常的通气功能。为验证这一假说，我们在6名健康人身上记录膈肌疲劳前后所进行的二氧化碳重复呼吸时的食道膈肌肌电压。采用具有4个电极对的多导食道电极导管记录膈肌电压，同时用胃食道球管法记录磁刺激下的食道、胃和跨膈肌电压。     

Esophagitis Dissecans Superficialis: Clinical,Endoscopic, and Histologic Features

Digestive Diseases and Sciences - Esophagitis dissecans superficialis (EDS) is a desquamative disorder of the esophagus, but there is a paucity of the literature regarding this condition. We...     

Acute dissociative reaction to spontaneous delivery in a case of total denial of pregnancy: Diagnostic and forensic aspects

This article presents the history of a 21-year-old female college student with total denial of pregnancy who experienced an acute dissociative reaction during the spontaneous delivery at home without medical assistance where the newborn died immediately. Psychiatric examination, self-report questionnaires, legal documents, and witness reports have been reviewed in evaluation of the case. Evidence pointed to total denial of pregnancy, that is, until delivery. The diagnoses of an acute dissociative reaction to stress (remitted) and a subsequent PTSD were established in a follow-up examination conducted 7 months after the delivery. Notwithstanding the inherently dissociative nature of total denial of pregnancy, no other evidence has been found about pre-existing psychopathology. For causing the newborn’s death, the patient faced charges for “aggravated murder,” which were later on reduced into “involuntary manslaughter.” Given the physical incapacity to perform voluntary acts due to the loss of control over her actions during the delivery, and the presence of an acute dissociative reaction to unexpected delivery, the legal case represents an intricate overlap between “insanity” and “incapacitation” defenses. The rather broad severity spectrum of acute dissociative conditions requires evaluation of the limits and conditions of appropriate legal defenses by mental health experts and lawyers. Denial of pregnancy as a source of potential stress has attracted little interest in psychiatric literature although solid research exists which documented that it is not infrequent. Arguments are presented to introduce this condition as a diagnostic category of female reproductive psychiatry with a more neutral label: “unperceived pregnancy.”     

Gay men's HIV testing behaviour in Scotland

This paper reports on the social and demographic factors associated with HIV testing in gay men in Scotland. Trained sessional research staff administered a short self-complete questionnaire to men in gay bars during January and February 1999 in Glasgow and Edinburgh, Scotland. Questionnaires were completed by 2,498 men (response rate of 77.5%). Half (1,190; 50%) reported ever having been HIV antibody tested, with men in Edinburgh more likely to report testing. Testing was associated with being older (26 years plus), higher education, reporting one unprotected anal intercourse (UAI) partner, or six or more UAI partners, in the last year, genitourinary medicine clinic service use, and lifetime experience of sexually transmitted infections. There was no relationship between HIV testing and treatment optimism, or evidence of a "post-Vancouver" effect. Over a fifth of men who said that they knew their own HIV status at last UAI had never been tested. Current testing policy needs to be challenged if there is to be an increase in the number of gay men who know their HIV status and, if tested HIV-positive, to then access antiretroviral treatments.     

Sensitivity of patients with familial cerebral cavernous malformations to therapeutic radiation

Familial cerebral cavernous malformations are autosomal dominant conditions that can result in significant morbidity. A two‐hit mechanism is accepted as likely responsible for formation of these malformations. We present two patients with this disease who received therapeutic radiation and developed very high numbers of malformations within the radiation ports, supporting radiation as an accelerator of lesion formation and suggesting implications for risks of radiation in this disease.