Spontaneous jaw muscle activity in patients with acquired brain injuries-Preliminary findings.

PATIENTS: High or excessive parafunctional jaw muscle activity is a frequent complication of acquired brain injury (ABI) and may have some similarities to bruxism. Bruxism has been associated with increased tooth wear, masseter hypertrophy and headaches. The aim of this observational study was to identify the levels of jaw muscle activity from fourteen ABI patients having different functional and cognitive levels in their early phase of neurological rehabilitation (according to their Ranchos Los Amigos Scale (RLAS) score). Nine patients were severely cognitive impairement (RLAS score 1-3): with no or little response to any external stimuli due to low arousal and five patients were with RLAS score 4-8: depending on responses to stimuli and confusion level i.e. defining that patients had enough arousal to respond and react and therefore were able to follow the instructions. A single-channel electromyographic (EMG) device was used to assess the jaw muscle EMG activity in ABI patients for two hours continuously at two different days. DISCUSSION: The mean (±SD) jaw muscle activity observed in patients with ABI was 46.9±6.5 EMG events/h with a wide range between 1-163 EMG events/h but with no significant difference between days (P=0.230). CONCLUSION: Irrespective of functional and cognitive ability scores patients with ABI had a wide range of EMG activity. The use of ambulatory single-channel EMG devices might open a path for further studies to determine levels of jaw muscle activity associated with potential side effects in ABI patients.

Determination of tobramycin in saliva is not suitable for therapeutic drug monitoring of patients with cystic fibrosis.

BACKGROUND: Tobramycin, used in the treatment of infections caused by Gram-negative bacteria, requires therapeutic drug monitoring (TDM) due to its narrow therapeutic index. The collection of blood for these assays may cause pain and trauma to the child and/or be difficult because of limited access to appropriate blood vessels. We undertook an evaluation of the role of saliva concentrations in the TDM of once-daily tobramycin therapy in patients with cystic fibrosis. METHODS: Fourteen patients (mean age 15 years) with cystic fibrosis were enrolled at Women's and Children's Hospital, Adelaide (WCH). All patients received once-daily dose of intravenous tobramycin for 2-3 weeks and had plasma levels measured once a week. At the same time of blood sampling at 1 and 6 h after initiation of tobramycin infusion, the patients also provided saliva samples. For collection of saliva, the Salivette (Sarstedt Laboratories) system was used which was developed specifically for saliva sampling. Concentrations in blood and saliva were measured by the Beckman Synchron CX system, which is utilized for routine assays of plasma tobramycin. RESULTS AND CONCLUSION: Tobramycin could not be detected in saliva within the first 6 h after a once-daily dosing. Therefore, plasma cannot be substituted with saliva for the TDM of tobramycin using the clinical routines at WCH.