Sensitivity for pressure difference on the ischial tuberosity.

Although research on sitting and sitting postures has been done for decades, the field of the subjective feeling of comfort or discomfort during sitting is still an unexplored field. On the basis of those studies some manufacturers claim enhanced subjective comfort because of pressure-relieving qualities of the seat cushions. The question is: does a relatively small pressure reduction enhance comfort? Before that question can be answered, the sensitivity for pressure differences applied to the skin must first be determined. The aim of this study was therefore, to determine the sensitivity of the ischial tuberosity for pressure difference in a healthy population. For this study five males and five females aged between 19 and 30 years with no exercise-induced muscle ache were selected. The (Deltaa) was determined for which stimulus (a + Deltaa) was judged as exceeding stimulus (a) in 50% of the trials. This value was called (Deltaa0.5) and was determined with an adapted simple up - down method with forced choice. Two different values for (a) were used: (a) = 13.3 kPa and (a) = 26.5 kPa and the pressure was applied with two different contact surface with diameters of 10 mm and 20 mm. For (a) = 26.5 kPa and d = 10 mm a Deltaa0.5 = 2.7 kPa was found. For (a) = 26.5 kPa and d = 20 mm a Deltaa0.5 = 3.5 kPa was found. For (a) = 13.3 kPa and d = 20 mm a Deltaa0.5 = 1.9 kPa was found.

Analysis of hearing loss after shunt placement in patients with normal-pressure hydrocephalus.

OBJECT: Following shunt placement for treatment of normal-pressure hydrocephalus (NPH), several patients suffered hearing loss. The authors undertook a study to analyze this outcome. METHODS: Sixteen patients in whom NPH was diagnosed were treated by placement of a ventriculoperitoneal shunt. Their hearing was assessed pre- and postoperatively by using pure tone audiometry. Two thirds of the ears tested showed a postoperative hearing loss of more than 10 dB. Recovery of the hearing loss occurred 6 to 12 weeks after shunt placement in 75% of the ears examined. CONCLUSIONS: Although shunt insertion for treatment of NPH results in a decrease in hearing, most of the loss can be recovered.

Persistent tachypnea in children: keep pulmonary embolism in mind.

PURPOSE: Tachypnea in children is associated with respiratory disorders and nonrespiratory disorders such as cardiac disease, metabolic acidosis, fever, pain, and anxiety. Pulmonary embolism is seldom considered by pediatricians as a cause of tachypnea. PATIENTS AND METHODS: Three children of various ages with persistent tachypnea are described: a girl after orthopedic surgery for kyphoscoliosis, a boy with nephrotic syndrome, and a neonate with Hirschsprung disease. Other causes of tachypnea were diagnosed and treated before pulmonary embolism was considered. RESULTS: Ventilation-perfusion scanning appeared to be highly probable for pulmonary embolism in these patients. Anticoagulant therapy was started. CONCLUSION: Pulmonary embolism should be kept in mind in children with tachypnea, especially when other risk factors for venous thromboembolism are present, to avoid delay in anticoagulant treatment and a fatal outcome.