Hyperactivity of N-methyl-D-aspartate (NMDA) receptors may be one of the factors in the genesis of neuropathic pain. Ketamine is an NMDA-blocking agent widely used in human medicine. Ketamine (at 250 mcg/kg i.v. slow push) was administered to 6 patients for control of chronic neuropathic pain syndromes in double-blind placebo-controlled fashion. All 3 patients with peripheral nervous system (PNS) disease-related pain, and 2 of 3 patients with central pain and dysesthesia syndromes responded with a temporary decrease in the rating of ongoing pain. The allodynia, hyperalgesia and after-sensation present in 5 patients improved after the administration of ketamine. Dose-response estimation in 2 patients with PNS-related neuropathic pain revealed that ketamine was effective in dose-related fashion. Continuous subcutaneous infusion of ketamine administered to 1 patient with PNS-related neuropathic pain caused no additional improvement in pain control but caused intolerable cognitive and memory side effects. In contrast, side effects during single-dose injections were mild and well tolerated. Ketamine affected the evoked pain and associated after-sensation in chronic neuropathic pain syndromes more than the ongoing constant pain.

The diagnostic significance of procalcitonin concentrations in lower respiratory tract infections and tuberculosis is not known. A prospective analysis was, therefore, performed in patients with acute exacerbation of chronic bronchitis (AECB), community-acquired pneumonia (CAP), hospital-acquired pneumonia (HAP) and tuberculosis and their procalcitonin levels compared with those of patients with noninfectious lung diseases (controls). In addition, standard inflammatory parameter data were collected.A prospective clinical study was performed with four different groups of patients and a control group that consisted of patients with noninfectious lung diseases. A total of 129 patients were included: 25 with HAP, 26 CAP, 26 AECB, 27 tuberculosis, and 25 controls. C-reactive protein level, blood cell counts and procalcitonin concentration were evaluated on the first day after onset of clinical and inflammatory symptoms prior to treatment.The median procalcitonin concentrations in HAP, CAP, AECB and tuberculosis were not elevated in relation to the cut-off level of 0.5 ng?mL -1 . In the HAP group, in four of five patients who subsequently died, procalcitonin concentrations ofw0.5 ng?mL -1 were found. In acute lower respiratory infections, such as HAP, CAP and AECB, significantly elevated levels were found in comparison to the control group, but below the usual cut-off level. No differences were observed between tuberculosis and the control group.Relative to the current cut-off level of 0.5 ng?mL -1 , procalcitonin concentration is not a useful parameter for diagnosis of lower respiratory tract infections. However, compared to the control group, there were significantly elevated levels in patients with hospital-acquired pneumonia, community-acquired pneumonia and acute exacerbation of chronic bronchitis below the current cut-off level, which should be further investigated. Eur Respir J 2003; 21: 939-943.

The WEB system allows one-lung ventilation to be achieved with a conventional endotracheal tube. The need for reintubation at the end of surgery is eliminated and endotracheal tube cross-sectional area is conserved.

No abstract

Intubation bougies are commonly used to aid in intubation when an optimal view of the larynx is not obtained. We describe a case of tracheal perforation using a disposable intubation bougie resulting in a complete intratracheal airway obstruction relieved by cricothyrotomy. Disposable intubation bougies may have mechanical properties that differ from their nondisposable counterparts making complications more likely.