The effect of meconium on neonatal and fetal reflectance pulse oximetry

Reflectance probes are being developed for neonatal use and obstetricians are beginning to use reflectance pulse oximetry to monitor the fetus. When a reflectance probe was used to monitor the arterial oxygen saturation of a baby whose skin was stained with meconium an artificially low result was obtained. This is because meconium absorbs more red than infra-red light and acts as a red light filter between the vascular bed and the probe. This effect may be reproduced by interposing a red filter between a reflectance pulse oximetry probe and the skin. Obstetricians who use a pulse oximeter to assess the fetus through intact membranes will record an erroneously low result if they are stained with meconium. Similarly neonatologists should avoid placing a reflectance pulse oximetry probe on babies skin which is stained with meconium.     

阿德福韦双酯治疗拉米夫定耐药的慢性乙肝患者时出现的耐药问题

背景:阿德福韦双酯(ADV) 是一种有效治疗野生型和耐拉米夫定乙肝病毒(HBV)的核苷酸类药物。在使用核苷酸类药物治疗慢性乙肝时,当治疗时间为 48、96、144周时,耐ADV变异体出现的累积发生率分别为0、 0．8-3％和0-5．9％。目的:研究67例对拉米夫定耐药且接受ADV治疗的慢性乙肝患者耐ADV病毒变异体的表型和基因型特点。方法:HBV DNA含量采用实时定量PCR技术。ADV变异体检测采用基质辅助激光解吸电离／飞行时间质谱为基础的基因分型     

Pre-natal ventriculomegaly and hydrocephalus

Ultrasonic imaging of the human fetal brain has allowed ventriculomegaly and hydrocephalus to be categorized. In this study 40 fetuses with ventriculomegaly and 21 with an Arnold-Chiari malformation and a myelomeningocele had ventriculomegaly that resolved, stabilised or progressed in utero. Within the progressive group were those with hydrocephalus, hydrocephalus being defined as expansion of the cerebral ventricular atria together with disproportionate increase in the head circumference. The prognosis for fetuses with resolving and stable ventriculomegaly was good, reflecting the fact that the ventricular dilatation in these cases was probably caused by delayed parenchymal and cerebrospinal fluid pathway development. Whereas the prognosis for progressive ventriculomegaly was generally poor, suggesting that the causes were likely to have been chromosomal, genetic, an infective agent or a catastrophic event which had an adverse effect on parenchymal development. The causes of hydrocephalus also adversely affected brain development but additional damage was caused by raised intracranial pressure.     

The fluctuation in recovery following whiplash injury 7.5-year prospective review

Forty-two patients with a whiplash injury were assessed at the time of injury, after 3 months, 2 years and a mean of 7.5 years. The range of neck movement, pain, its effect on lifestyle, and psychometric testing were determined in each of the patients. Between 2 and 7.5 years, 5 (12%) described improved symptoms, 12 (29%) complained of continuing pain and 14 (33%) reported increased severity of symptoms since the accident. Neck pain was the commonest complaint in 23 (55%) and low back pain in 18 (43%). Radiation of pain was more common in the severely symptomatic patients. There was no significant difference in either the ages or sex of the patients between the symptomatic and asymptomatic groups. Anxiety and depression correlated well with symptom severity. None of the asymptomatic patients revealed any degree of psychological disturbance compared with 30 (77%) in the symptomatic groups. Symptoms largely stabilised within 3 months but there was significant fluctuation in symptom severity between 3 months and 2 years. This suggests that outcome cannot be accurately assessed during this time. In order to effectively manage those most severely affected by whiplash, patients should be identified within the first 12 weeks following injury if the outcome of their injury is to be modified.     

The use of lisuride in the treatment of multiple system atrophy with autonomic failure (Shy-Drager syndrome).

In a controlled trial lisuride, an ergolene derivative with dopamine receptor agonist properties was given maximum tolerated doses (2.4 mg/day) to seven patients with multiple system atrophy with autonomic failure (Shy-Drager syndrome). Improvement in Parkinsonian features occurred in only one patient and another patient who had been deriving marked benefit from levodopa treatment before the study began failed to respond to large doses of lisuride. Psychiatric side effects (including nightmares, isolated visual hallucinations and toxic confusional states) were the dose-limiting factor in six patients. A modest reduction in orthostatic hypotension occurred in two patients, one of whom had experienced an aggravation of this disturbance on levodopa and bromocriptine. Destruction of post-synaptic dopamine receptors and damage to central noradrenergic systems may offer an explanation for the lack of therapeutic effect of lisuride.