Advanced high pressure hyperbaric techniques in tunnelling.

Work in compressed air and diving are both occupational activities that have been around since the mid-19th century, and those undertaking their work under elevated pressure. Meeting the demand to go to "higher pressure for longer" in tunneling has lagged in diving, but both activities have found it necessary to adopt mixed gas breathing and saturation exposure techniques. This paper explains how work in hyperbaric conditions at high pressure is undertaken in tunneling and is illustrated by the hyperbaric activity likely to be involved in constructing a large-diameter road tunnel below a body of water such as an estuary. It also explores the practical differences between work in compressed air and diving.

Shunt-mediated decompression sickness in a compressed air worker with an atrial septal defect.

We report a compressed air worker who had diffuse cutaneous decompression sickness with pain in his left shoulder and visual disturbance characteristic of migraine aura after only his third hyperbaric exposure. The maximum pressure was 253 kPa gauge with oxygen decompression using the Swanscombe Oxygen Decompression Table. He was found to have a very large right-to-left shunt across a 9 mm atrial septal defect. He had transcatheter closure of the defect but had some residual shunting with release of a Valsalva manoeuvre. Thirty-two other tunnel workers undertook the same pressure profile and activities in the same working conditions during the maintenance of a tunnel boring machine for a total of 233 similar exposures and were unaffected. As far as we are aware this is the first report of shunt-mediated decompression sickness in a hyperbaric tunnel worker in the United Kingdom and the second case reported worldwide. These cases suggest that shunt-mediated decompression sickness should be considered to be an occupational risk in modern compressed air working. A right-to-left shunt in a compressed air worker should be managed in accordance with established clinical guidance for divers.

Serotonin effects on sleep and emotional disorders in adolescent migraine.

OBJECTIVE: To determine frequency of emotional disorders and sleep disturbances in adolescent migraineurs with episodic and chronic headaches. To determine the relationship of whole blood serotonin, caffeine consumption, and frequency of sleep and mood disorders. BACKGROUND: The neurotransmitter serotonin has been implicated to play a role in the initiation and maintenance of sleep and in modulating mood. A putative role in migraine pathophysiology is also known. METHODS: Adolescents from 13 to 17 years of age were identified from our headache clinic with episodic or chronic migraine (according to International Classification of Headache Disorders-Second Edition criteria) and healthy controls enrolled. Psychological rating scales were completed, including Adolescent Symptom Inventory (4th Edition) and Child Depression Inventory. Sleep questionnaires (Pediatric Sleep Questionnaire and Child Sleep Habit Questionnaire) were completed by the teenager's parents/guardian. Whole blood serotonin levels were drawn and analyzed and caffeine consumption obtained by history. RESULTS: A total of 18 controls (8 girls) and 15 patients each with episodic migraines (9 girls) and chronic migraine (10 girls) were studied. Patients with headache had significantly more sleep problems than controls. Patients with chronic migraines had increased daytime sleepiness and dysthymia compared with teenagers with episodic migraines. Serotonin levels were not significantly different, and no association was noted between serotonin levels and sleep abnormalities or emotional rating scales. Increased caffeine intake was related to sleep and depressive complaints. CONCLUSIONS: Sleep and emotional disorders were common in adolescents with migraine. Sleep disorders and dysthymia were more prevalent with increased headache frequency. No correlation was noted with whole blood serotonin levels.

A survey of parent satisfaction with pediatric neuropsychological evaluations.

Satisfaction with pediatric neuropsychological evaluations was surveyed by asking parents or guardians of children who completed pediatric neuropsychological evaluations at a large children's hospital over a 2-year period to complete a 30-item rating scale. The scale included items drawn from published measures of consumer satisfaction, and incorporated a well-validated measure of general satisfaction. A total of 338 surveys were distributed, with 117 completed, for a return rate of 35%. Respondents were generally similar to non-respondents, except that respondents had a higher average level of maternal education and were more likely to have been referred for neuropsychological evaluations by sources outside the hospital. Parents were generally satisfied with pediatric neuropsychological evaluations, although some parents indicated that the evaluations did not provide as much help as expected. A factor analysis of the survey instrument revealed four dimensions of satisfaction: General Satisfaction, Clinician Acceptance/Empathy, Provision of Help, and Facilities/Administrative Assistance. Maternal education was negatively correlated with all four factors, but no other demographic, patient, or clinician variables were significantly related to satisfaction. Future studies could survey physicians and educators to provide a more complete understanding of satisfaction with pediatric neuropsychological evaluations.

Comorbidity of psychiatric and behavioral disorders in pediatric migraine.

OBJECTIVE: To determine whether behavioral and psychiatric disorders occur more frequently in school-age children with migraine headache. To also elucidate treatment response related to comorbid psychiatric or behavioral diagnosis. BACKGROUND: Recurrent migraine headaches are common in school-age children. Concurrent behavioral or psychiatric diagnoses could significantly impact headache frequency, severity, and response to treatment. METHODS: Healthy children from 6 to 17 years of age presenting to our headache clinic with migraine headache according to International Headache Society (IHS) criteria were identified. Parents/guardians were asked to complete the Child Symptom Inventory, 4th edition (CSI-4) after written informed consent. Children with positive rating scales underwent psychological interviews for confirmatory diagnosis. Results were compared to controls. Headache patients were assigned our usual treatment paradigm. Response regarding headache frequency was assessed at 3 months. RESULTS: A total of 47 patients were diagnosed with migraine headaches. The mean age was 10.55 years. Thirty controls were identified. After completing the CSI-4 and confirmatory psychological interview, 14 of 47 headache patients fulfilled Diagnostic and Statistical Manual (DSM-4) criteria for a psychiatric or behavioral disorder. Oppositional defiant disorder (ODD) was significantly represented among children with migraine compared to the control group of children. Headache patients improved significantly post-treatment regarding their headache frequencies regardless of comorbid psychiatric or behavioral disorder. No significant differences were noted between boys and girls regarding diagnoses or treatment outcome. CONCLUSION: ODD was a significant comorbidity in our headache population. Although families complained of significant behavioral symptomatology in their children, most of these symptoms did not qualify their children for a psychiatric diagnosis and may be related to the stressors of headache on social/school disruption.

Synthesis of meso-arylsulfanyl- and alkylsulfanyl-substituted porphyrins via palladium-mediated C-S bond formation.

A family of new meso-arylsulfanyl- and alkylsulfanyl-substituted porphyrins were efficiently synthesized from direct reactions of meso-brominated porphyrins with thiols via palladium-mediated C-S bond formation. The catalytic method can be performed under mild conditions with both mono- and bis-substituted meso-bromoporphyrins as well as their zinc complexes and is suitable for different types of thiols. With the use of selenols, meso-seleno-substituted porphyrins can also be prepared similarly.

Versatile synthesis of meso-aryloxy- and alkoxy-substituted porphyrins via palladium-catalyzed C-O cross-coupling reactions.

[reaction: see text] meso-Aryloxy- and alkoxy-substituted porphyrins were conveniently synthesized by direct reactions of meso-halogenated porphyrins with alcohols via palladium-catalyzed C-O cross-coupling reactions. Using a combination of palladium precursor Pd(OAc)(2) or Pd(2)(dba)(3) and phosphine ligand DPEphos or Xantphos allowed both 5-bromo-10,20-diarylporphyrin and 5,15-dibromo-10,20-diarylporphyrin, as well as their zinc complexes, to be effectively coupled with a variety of alcohols to give the corresponding mono- and bis-substituted meso-aryloxy/alkoxyporphyrins in moderate to high yields under mild conditions.

Motor adaptation in children with myelomeningocele: comparison to children with ADHD and healthy siblings.

Myelomeningocele is a common developmental malformation of the central nervous system that usually results in motor deficits. Previous studies of myelomeningocele have not examined motor adaptation, which involves changes in the control of movements that occur as a result of repeated task exposure but do not depend on conscious recall of the exposure. We studied motor adaptation in 17 children with myelomeningocele and shunted hydrocephalus, 19 children with attention deficit/hyperactivity disorder (ADHD), and 20 healthy siblings. All children were 8 to 15 years of age. They were administered 2 measures of motor adaptation known to be sensitive to subcortical abnormalities in adult neurological disorders. One task assessed the biasing in weight judgments that occurs after exposure to heavy versus light weights, and the other assessed the adaptation in reaching movements that occurs when vision is laterally displaced by prisms. Contrary to expectations, the groups did not differ in motor adaptation. Children in all 3 groups displayed significant biasing in their weight judgments and improvement in the accuracy of pointing during prism adaptation trials. Performance on the 2 motor adaptation tasks was not related to age or IQ. Weight biasing was positively related to a measure of response disinhibition. The findings suggest that myelomeningocele does not result in global impairment of motor skills, but instead in a profile of intact and impaired motor functions that potentially may be decomposed in accordance with the neuroscience of motor skills.

Do children with myelomeningocele and hydrocephalus display nonverbal learning disabilities? An empirical approach to classification.

As a group, children with myelomeningocele (MM) and early-onset hydrocephalus demonstrate many of the features of the syndrome of nonverbal learning disabilities (NLD). However, the frequency with which individual children display a pattern of neuropsychological functioning consistent with the NLD syndrome is unknown. We addressed this question by comparing the prevalence of NLD in 32 children with MM and shunted hydrocephalus to that in a group of 27 healthy siblings. Participants, who were between 8 and 15 years of age, completed a neuropsychological test battery that included 11 measures of possible assets and 17 measures of possible deficits that define the NLD syndrome. As a group, children with MM and shunted hydrocephalus displayed many of the specific assets and deficits. However, they also displayed significantly more variability in their patterns of assets and deficits than siblings, reflecting the substantial individual differences that characterize children with MM. About 50% of the children with myelomeningocele displayed a pattern of assets and deficits consistent with the NLD syndrome. Classification as NLD was weakly related to cumulative medical risk, as well as to left-handedness. The findings suggest a need for caution in making generalizations regarding the applicability of the NLD model to children with MM and early-onset hydrocephalus.

Long-term executive function deficits in children with traumatic brain injuries: assessment using the Behavior Rating Inventory of Executive Function (BRIEF).

Long-term deficits in executive functions following childhood traumatic brain injuries (TBI) were examined using the Behavior Rating Inventory of Executive Function (BRIEF). Parents completed the BRIEF approximately 5 years postinjury as part of a prospective study of children injured between the ages of 6 and 12. The children were between 10 and 19 years of age at the time of the assessment, and included 33 with severe TBI, 31 with moderate TBI, and 34 with orthopedic injuries. Parents also rated children's adaptive functioning and completed several other measures of parent and family functioning. Children were administered a neuropsychological test battery that included several measures of executive functions. The groups displayed a significant linear trend in BRIEF scores, with the largest deficits in executive functions reported in children with severe TBI. BRIEF scores were related consistently across groups to a test of working memory, but not to other neuropsychological measures. BRIEF scores also predicted children's adaptive functioning and behavioral adjustment, as well as parent psychological distress, perceived family burden, and general family functioning. The findings indicate that TBI results in long-term deficits in executive functions that are related to children's psychosocial outcomes, as well as to parent and family functioning.