The immediate effect of changing mandibular position on the EMG activity of the masseter, temporalis, sternocleidomastoid, and trapezius muscles

This study investigated the immediate effect of changing mandibular position on the electromyographic (EMG) activity of the masseter (MS), temporalis (TM), sternocleidomastoid (SCM) and trapezius (TR) muscles. Thirty-three (33) asymptomatic subjects (16 males and 17 females), ages 23 to 52 were selected. Surface EMG recordings were obtained for all muscles bilaterally with the mandible in a relaxed open position (relaxed) and during maximal voluntary clenching (fullbite) for the following: a non-repositioning appliance (NONREPOS) and repositioning appliance (REPOS). REPOS significantly reduced EMG activity of all muscles bilaterally during fullbite. During relaxation, reduction in EMG activity was only found for TR bilaterally. NONREPOS decreased the EMG activity bilaterally for TM and TR and unilaterally (left) for MS and SCM during fullbite. During relaxation, NONREPOS decreased muscle activity bilaterally for TR and SCM. A unilateral reduction was found for TM (right). These findings suggest that immediate alterations in mandibular position affect the cranio-cervical system. Both mandibular positions tested lowered the EMG activity of masticatory and cervical muscles in the relaxed and fullbite positions. The trapezius muscle was the most responsive to alterations in mandibular position.     

Effects of colonoscopy on intracranial pressure: observation in a large animal model

BACKGROUND AND STUDY AIMS: Increased intra-abdominal pressure has been associated with increased intracranial pressure. Bowel insufflation during colonoscopy may increase the intra-abdominal pressure. It was hypothesized that colonoscopy may be associated with intracranial pressure elevation subsequent to an elevation in intra-abdominal pressure. MATERIALS AND METHODS: Colonoscopy was carried out in seven anesthetized pigs, and the colonoscope was advanced up to 60 cm from the anal verge. Insufflation was used to allow safe advancement of the colonoscope and to allow visualization of the colon, in the same way as in the procedure performed in humans. Intra-abdominal pressure was measured by determining the hydrostatic pressure in the urinary bladder. A subarachnoid screw was used to monitor intracranial pressure. The mean arterial blood pressure and intra-abdominal venous pressure were directly monitored via the femoral vessel access; all parameters were recorded before and during colonoscopy. RESULTS: A statistically significant elevation in intracranial pressure was demonstrated during colonoscopy. The average increase in intracranial pressure was 3.1 mm Hg. The intra-abdominal pressure and intra-abdominal venous pressure were also significantly elevated during the procedure. CONCLUSIONS: Colonoscopy may increase intracranial pressure due to an increase in intra-abdominal pressure. This may have clinical implications when colonoscopy is conducted in patients with brain pathology associated with high intracranial pressure.     

Active sodium-urea counter-transport is inducible in the basolateral membrane of rat renal initial inner medullary collecting ducts.

Rat inner medullary collecting ducts (IMCD3s) possess a luminal Na+-dependent, active urea secretory transport process, which is upregulated by water diuresis. In this study of perfused IMCDs microdissected from base (IMCD1), middle (IMCD2), or tip (IMCD3) of the inner medulla, we tested whether furosemide diuresis alters active urea transport. Rats received furosemide (10 mg/d s.c. for 3-4 d) and were compared with pair-fed control rats. Furosemide significantly decreased urine osmolality and urea clearance, and increased blood urea nitrogen. IMCD3s from furosemide-treated rats had significantly lower rates of active urea secretion than IMCD3s from control rats. IMCD2s showed no active urea transport in control or furosemide-treated rats. IMCD1s from control rats had no active urea transport, but IMCD1s from furosemide-treated rats expressed significant rates of active urea reabsorption. In IMCD1s, this active urea reabsorptive transport process was inhibited by: (i) 0. 25 mM phloretin (bath); (ii) 1 mM ouabain (bath); and (iii) replacing bath Na+ with NMDG+; it was stimulated by 10 nM bumetanide (bath). In summary, we found that furosemide decreased active urea secretion in IMCD3s and induced active urea reabsorption in IMCD1s. The new Na+- dependent, active urea reabsorptive transport process may be a basolateral Na+-urea antiporter.     

Double-blind study of endotracheal tobramycin in the treatment of gram-negative bacterial pneumonia. The Endotracheal Tobramycin Study Group.

A prospective, double-blind, placebo-controlled study was conducted to determine the safety and efficacy of endotracheal tobramycin (ETT) for treatment of gram-negative bacterial pneumonia. Patients were randomized to either 40 mg of tobramycin or a placebo instilled endotracheally every 8 h. Patients also received intravenous tobramycin plus either cefazolin or piperacillin. Of 85 patients enrolled, 41 were assessable. Most microbiologic diagnoses were made by endotracheal aspiration with strict grading criteria. The clinical-radiographic responses of patients and standard demographic data were recorded. Pseudomonas aeruginosa, "multiple pathogens," and Klebsiella-Enterobacter-Serratia-Citrobacter species were isolated in 41, 32, and 15% of the instances, respectively. Causative pathogens were eradicated from sputum significantly more frequently by patients who received ETT (P less than 0.05). However, no significant differences were noted in the clinical outcomes of the two study groups. No local adverse reactions attributable to the administration of this agent were observed, but four patients had supraventricular tachycardia, compared with none who received the placebo (P = 0.053). ETT may be considered as adjunctive therapy for seriously ill individuals.     

Perceptions of crisis care in populations who self‐referred to a telephone‐based mental health triage service

Although psychiatric crises are very common in people with mental illness, little is known about consumer perceptions of mental health crisis care. Given the current emphasis on recovery‐oriented approaches, shared decision‐making, and partnering with consumers in planning and delivering care, this knowledge gap is significant. Since the late 1990s, access to Australian mental health services has been facilitated by 24/7 telephone‐based mental health triage systems, which provide initial psychiatric assessment, referral, support, and advice. A significant proportion of consumers access telephone‐based mental health triage services in a state of crisis, but to date, there has been no published studies that specifically report on consumer perceptions on the quality and effectiveness of the care provided by these services. This article reports on a study that investigated consumer perceptions of accessing telephone‐based mental health triage services. Seventy‐five mental health consumers participated in a telephone interview about their triage service use experience. An eight‐item survey designed to measure the responsiveness of mental health services was used for data collection. The findings reported here focus on the qualitative data produced in the study. Consumer participants shared a range of perspectives on telephone‐based mental health triage that provide invaluable insights into the needs, expectations, and service use experiences of consumers seeking assistance with a mental health problem. Consumer perceptions of crisis care have important implications for practice. Approaches and interventions identified as important to quality care can be used to inform educational and practice initiatives that promote person‐centred, collaborative crisis care.     

Complications and side effects associated with epidural bupivacaine/morphine analgesia

Postoperative analgesia is a responsibility that physicians should fulfil in every patient. It is not only an act of kindness, but also an improved clinical outcome may be derived from this service when epidural techniques are used. However, complications and side effects may occur with postoperative epidural analgesia. Thus, there have been concerns among some clinicians regarding the use of local anaesthetics and opioids for epidural analgesia in the surgical wards where monitoring of patients is not as strict as it is in critical care or step down units. A review of the literature reflects a low incidence of side effects and complications in the surgical wards where the nursing staff have been trained in the early recognition of potential complications and the treatment of side effects. Many issues remain to be addressed via further research efforts. However, we believe that the current knowledge on potential complications and side effects of postoperative epidural analgesia and their treatment, allow for the safe epidural delivery of combinations of local anaesthetics and opioids in a wide range of postoperative patients. We also present the protocols that we currently use in our Acute Pain Treatment Service for the management of these complications and side effects.