The role of endobronchial electrocautery in the management of malignant airway obstruction.

Bronchoscopy has evolved well beyond a simple look-see examination, with new interventional techniques becoming more commonly employed. So-called interventional bronchoscopy implies the use of bronchoscopy as a therapeutic, in addition to diagnostic, tool. We present 2 cases to illustrate the utility of one such interventional technique, tumour ablation by endobronchial electrocautery and snaring, in the management of airway obstruction by tumour. This procedure, performed via a flexible bronchoscope under local anaesthesia can spare patients time-consuming, expensive treatments with their attendant morbidity, and in some cases can be life-saving. There is minimal morbidity associated with this technique. It is anticipated that interventional bronchoscopy will continue to revolutionise management of such conditions in the future, and become a necessary facility in all pulmonary medicine units.

Evaluation of the efficacy of nebulised lignocaine as adjunctive local anaesthesia for fibreoptic bronchoscopy: a randomised, placebo-controlled study.

Optimisation of topical anaesthesia for flexible fibreoptic bronchoscopy (FOB) is becoming increasingly important as a wider range of more complex, and thereby more prolonged, interventional endoscopic procedures are becoming available. Lignocaine is the most commonly used topical anaesthetic agent for bronchoscopy, but there is variability in current practice as to its optimum mode of administration. In this prospective, randomised, placebo-controlled, blinded study, we examine whether there was enhanced effectiveness of additional nebulised lignocaine as compared to our current regime utilising two visual analogue scales as markers of efficacy. Treatment groups were matched in terms of age (p = 0.39), gender, concomitant sedation (p = 0.51 midazolam; p = 0.12 fentanyl) and dose of background administered lignocaine (290 mg). We found no significant additional differences between any of the treatment groups in terms of general ease of procedure (p = 0.09) or in cough severity (p = 0.12). We conclude that this study does not support the hypothesis that additional nebulised lignocaine confers any additional benefit to the ease of procedure or cough severity in patients undergoing fibreoptic bronchoscopy. We suggest that preparation regimes for bronchoscopic examinations need optimization.

An electrogenic component of the potential difference in the rabbit lens.

The normal resting potential of the rabbit lens, -70mV, is altered to -59mV by ouabain concentrations up to 5-1- minus 6M, and to -52mV at 4 degrees C. Ouabain acts only at the anterior lens surface. The temperature effect id completely reversible. The Hodgkin-Katz-Goldman equation can be used with the measured lens potentials and Na+ and K+ levels in the lens and bathing medium to obtain alpha, the ration of the membrane permeabilities to Na+ and K+. The alpha-values obtained were 0.052 at 4 degrees C and 0.053 in 5-10 minus 6M ouabain. These data suggest that the change in potential due to cold and ouabain is caused by an inhibition of an electrogenic Na+ ump in the anterior lens epithelium.

Endothelial cells inhibit flow-induced smooth muscle cell migration: role of plasminogen activator inhibitor-1.

BACKGROUND: The endothelium may play a pivotal role in hemodynamic force-induced vascular remodeling. We investigated the role of endothelial cell (EC) plasminogen activator inhibitor-1 (PAI-1) in modulating flow-induced smooth muscle cell (SMC) migration. METHODS AND RESULTS: Human SMCs cocultured with or without human ECs were exposed to static (0 mL/min) or flow (26 mL/min; shear stress 23 dyne/cm(2)) conditions for 24 hours in a perfused capillary culture system. SMC migration was then assessed with a Transwell migration assay. In the absence but not in the presence of ECs, pulsatile flow significantly increased the migration of SMCs (264+/-26%) compared with SMCs under static conditions, concomitant with a 3- and 4-fold increase in PAI-1 mRNA and protein, respectively, in cocultured ECs. In the presence of PAI-1-/- ECs, flow increased wild-type SMC migration (226+/-25%), an effect that was reversed by exogenous PAI-1. To determine whether the antimigratory activity of PAI-1 was dependent primarily on inhibition of PAs or its association with vitronectin, experiments were conducted with PAI-1R (a mutant PAI-1 that binds to vitronectin but does not inhibit PA) and PAI-1K (a mutant that inhibits PA but has reduced affinity for vitronectin). PAI-1R inhibited both basal and flow-induced migration, whereas PAI-1K inhibited flow-induced migration in the absence of any effect on baseline migration. CONCLUSIONS: Flow-induced EC PAI-1 inhibits flow-induced SMC migration in vitro. EC PAI-1 expression may be one of the predominant mechanisms responsible for controlling the process of vascular remodeling.

The implementation of a nurse-provided, ward-based bilevel non-invasive ventilation service.

Bilevel non-invasive ventilation (NIV) is now standard of care for patients with acute hypercapnic respiratory failure (AHRF), and has an increasing role to play in patients with stable chronic hypercapnic respiratory failure (CHRF). The institution of an NIV service in a hospital setting requires major infrastructural and multidisciplinary input to be effective. This paper describes our experiences in setting up a 24-hour, nurse-provided, ward-based NIV service in a new acute teaching hospital in Dublin over a 39-month period. In addition, we provide audit data on 78 patients with AHRF treated with NIV by this service over this time period. The majority of patients (65) had their respiratory acidosis corrected and were discharged home; 11 patients failed NIV and were intubated and mechanically ventilated in the ITU; 13 patients died, 8 from respiratory causes and 5 from non-respiratory causes, indicating the critical nature of this condition.

Use of A-192621 to provide evidence for involvement of endothelin ET(B)-receptors in endothelin-1-mediated cardiomyocyte hypertrophy.

Increased plasma levels of endothelin-1 correlate with the severity of left ventricular hypertrophy in vivo. The aim of the study was to determine the relative contribution of stimulation of endothelin ET(A) and endothelin ET(B) receptors, and the associated activation of protein kinase C, to the hypertrophic response initiated by endothelin-1 in adult rat ventricular cardiomyocytes maintained in culture (24 h). Endothelin-1 (10(-7) M) increased the total mass of protein and the incorporation of [14C] phenylalanine into protein to 26% and 25% greater (P<0.05) than respective basal values. The total content of RNA and the incorporation of 2-[14C] uridine into RNA were increased by 23% and 21%, respectively, by endothelin-1 (10(-8) M). Actinomycin D (5x10(-6) M), an inhibitor of transcription, abolished the incorporation of [14C] phenylalanine and the increased protein mass elicited by endothelin-1 (10(-8) M). The selective agonists at the endothelin ET(B) receptor, sarafotoxin 6c (10(-7) M) and endothelin-3 (10(-7) M), increased the incorporation of [14C] phenylalanine to 13% and 13% greater than respective basal values. The incorporation of [14C]phenylalanine in response to endothelin-1 (10(-7) M) was reduced by 50% (P<0.05) by the selective antagonist at endothelin ET(A) receptors, ABT-627 (10(-9) M), while the response to sarafotoxin 6c was not attenuated. The selective antagonist at endothelin ET(B) receptors, A192621 (10(-10) M), abolished the response to sarafotoxin 6c (10(-7) M) and attenuated the response to endothelin-1 (10(-7) M) by 43% (P<0.05). The selective inhibitor of protein kinase C, bisindolylmaleimide (5x10(-6) M) attenuated the response to sarafotoxin 6c (10(-7) M) by 78% and that to endothelin-1 (10(-7) M), elicited in the presence of A192621 (10(-10) M), by 52%. In conclusion, these data implicate endothelin ET(B) receptors, in addition to endothelin ET(A) receptors, in endothelin-1-mediated cardiomyocyte hypertrophy and provide evidence for the involvement of protein kinase C, at least in part, in the hypertrophic signalling pathways associated with activation of each receptor subpopulation.

Simulated Bennett fracture treated with closed reduction and percutaneous pinning. A biomechanical analysis of residual incongruity of the joint.

UNLABELLED: Contact area and contact pressure within the trapeziometacarpal joint were measured during static and dynamic loading in a cadaver model. The measurements were repeated after a Bennett fracture had been simulated with use of an osteotomy of the metacarpal base. The beak fragment was recessed two millimeters and was fixed in close apposition to maintain the integrity of the palmar beak ligament, and contact area and contact pressure were measured during lateral pinch. Despite the resulting articular incongruity, the mean total contact area of the joint surface increased from 15.8 to 25.8 square millimeters (63 per cent) in all specimens after simulation of the Bennett fracture (p = 0.02), and it shifted dorsally in moderately osteoarthrotic and non-osteoarthrotic specimens. The mean contact area in the palmar region of the joint surface decreased, from 58 to 25 per cent of the total area (p = 0.04); that in the central region increased, from 28 to 52 per cent (p = 0.05); and that in the dorsal region increased, but not significantly with the numbers available, from 14 to 24 per cent (p = 0.18). No pathological concentration of contact pressure was seen at the margin of the articular step-off. The changes in area and pressure reflect an unloading of the metacarpal beak, where osteoarthrotic degeneration most commonly occurs. CLINICAL RELEVANCE: There is no biomechanical basis for predisposition to post-traumatic osteoarthrosis after a Bennett fracture with a small palmar-beak component and a residual two-millimeter articular step-off, provided that the fragments of the shaft and the beak heal in close apposition. This suggests that reduction of the metacarpal shaft relative to the trapezium and the beak fragment, rather than strict anatomical restoration of the joint surface, should be the priority of treatment. Bennett fractures that can be reduced with articular incongruity of no more than two millimeters may be treated satisfactorily with closed reduction and percutaneous pinning without the need for open anatomical reduction and internal fixation of the joint surface.

The neurologic sequelae of cervical spine facet injuries. The role of canal diameter.

Neurologic outcomes were correlated with the cervical canal diameter for 33 patients who sustained unilateral or bilateral facet fractures, dislocations, subluxations, or perch injuries during a 9-year period. Lateral roentgenograms (target distance, 72 in.) were used to measure the canal and calculate the canal-body ratio (Torg's ratio) at the level of the vertebral injury. Frankel's classification system was employed to compare initial and final neurologic function. The most important factors that determined the long-term functional results after unilateral or bilateral injuries in the cervical spine were the degree of vertebral trauma and the severity of the initial neurologic deficit. There was no correlation between the preinjury canal diameter or ratio and the severity of neurologic injury or the prognosis. Also, neurologic injuries were more common and more severe in patients with bilateral facet injuries. No patients with complete injuries had an improvement in their Frankel grade.

Practices and attitudes of postsecondary LD service providers in North America.

A nationwide survey of 510 postsecondary LD service providers was conducted to determine (a) the types of interventions utilized by service providers, and (b) their attitudes toward the needs of adults with learning disabilities. The results of this study revealed that an educationally diverse group of professionals have been given the responsibility of developing programs and providing direct instruction to individuals with LD. The proliferation of services found in this survey is analogous to a "menu" of options, with little or no philosophical base. Findings suggest that service providers should be encouraged to utilize interventions that lead to self-determination and independence for adults with LD.

Operationalizing a definition of learning disabilities.

Past, present, and future concerns regarding the definition of learning disabilities (LD) are documented. Research on efforts to clarify the LD label is discussed, with a focus on the questionable utility of the discrepancy model. Finally, an approach to operationalizing the NJCLD definition of LD is presented and applied.

Auditing a new lung cancer service.

The Adelaide and Meath Hospital (AMNCH) is a new hospital, with the respiratory service established in 1999. We report on our experience with lung cancer in this short time. We conducted a retrospective chart audit, identifying patients from the Oncology Nurse patient list, of lung cancer cases diagnosed in 2001-2002. In 2001, 47 cases were diagnosed, with 71 cases diagnosed in 2002. Time to tissue diagnosis was 14.8, 2-46 (mean, range, one subject skewing the data) days. Diagnosis by tissue type was as follows: non-small cell carcinoma (NSCLC) n=92 (77.9%), small cell lung carcinoma (SCLC) n=17 (14.4%), mesothelioma n=2 (17%), carcinoid n=1 (0.8%) and no tissue diagnosis n=6 (5.1%). Staging of NSCLC: stage 1a n=3 (3.2%), stage 1b n=6 (6.5%), stage 2a n=5 (5.4%), stage 2b n=2 (2.2%), stage 3a n=10 (10.9%), stage 3b n=22 (23.9%) and stage 4 n=44 (47.8%). Staging of SCLC: limited stage n=5 (29.4%), extensive stage n=12 (70.6%). Positive emission tomography (PET) was employed in the staging of 22 patients. In these patients PET up-staged the disease in 8 patients, and management was unchanged in 8 patients. We conclude that 1. the relatively new respiratory service in AMNCH is handling increasing numbers of lung cancer cases, 2. cases are diagnosed within an acceptable time-frame, 3. rate of tissue diagnosis is comparable to national figures, 4. most patients present with advanced disease and 5. PET is a useful imaging modality for detection of cancer spread in selected patients.

A psychosocial evaluation process for living liver donors: the University of Rochester model.

OBJECTIVE: The donation of livers by living donors entails complex processes, both surgically and psychosocially, potentially involving risks in both domains. Thorough psychosocial evaluation is necessary to minimize those risks, yet little has been written about the donor assessment process. This article describes one such process, utilized by a transplant program in upstate New York. METHOD: Donor candidates undergo multiple psychosocial interviews early in the overall transplant evaluation process. Evaluators subsequently meet as a group, along with an independent ethicist, to determine psychosocial candidacy prior to final medical/surgical clearance. RESULTS: Between 2003 and 2007, 416 donor candidates initiated and/or underwent full evaluation, resulting in a 17.5% surgery and 55.5% exclusion rate among those individuals. Of those ruled out, 20.8% were for (medical or psychosocial) reasons associated with the recipient, and 8.7% were for donor-related psychosocial issues. CONCLUSION: Given the primacy ofpsychosocial and ethical issues in living liver donor candidate evaluation, the multiple interview process, followed by team discussion and overseen by an ethicist removed from other transplant program functions, has advantages as a donor assessment model.

Detection of inspiratory resistive loads after anaesthesia for minor surgery.

We measured the ability to detect inspiratory resistances in 22 patients undergoing minor gynaecological surgery, using linear resistances of 1.2-24.4 cm H2O litre-1 s, and ranked 1-9. The rank that could be detected was measured before surgery, approximately 10 min after recovery from anaesthesia, and then 25 min later. After anaesthesia there was a significant increase (P < 0.001) in the rank number by 2, which returned to preoperative values 25 min later. Minute ventilation was reduced by 25% after operation and this may partly explain this change; however, we believe the transient decrease in ability to sense resistance indicates residual effects of anaesthetics and may explain in part the incidence of hypoxia caused by airway obstruction in patients after anaesthesia.

Treatment of traumatic radioulnar synostosis by excision and postoperative low-dose irradiation.

Post-traumatic radioulnar synostosis can have a profound effect on upper extremity function. Prior reports of excision, with and without interposition material, have demonstrated frequent recurrence and disappointing results. Based on a favorable experience with radiation prophylaxis of heterotopic ossification following total hip arthroplasty, this modality has been used in the management of post-traumatic forearm synostosis. Four cases using excision of bony synostosis followed by single-fraction, low-dose (800 cGy), limited-field irradiation are presented. With a follow-up period of 1-4 years after excision and irradiation, all four patients had total arcs of forearm rotation between 115 degrees and 120 degrees. Each patient noted sustained functional improvement, and there was no x-ray film evidence of recurrent synostosis formation. Single fraction irradiation did not require ongoing patient compliance nor did it complicate rehabilitative efforts. Furthermore, soft tissue and bony healing were not impaired.

Protective action of phenytoin in cerebral ischemia.

Thirty-six rabbits were subjected to 15-minute periods of stagnant cerebral hypoxia while blood flow to the rest of the body was preserved. After this ischemic interval the animals, divided into three groups, received either saline, phenytoin, 15 mg/kg IV, or thiopental 10 mg/kg IV and 10 mg/kg IM. Histologic examination of tissue sections of the brains, 72 hours after ischemia, indicated that phenytoin afforded significant protection (p less than 0.001) of neurons in the hippocampus and in the dentate nucleus when compared to saline, while the findings noted after thiopental were not statistically significant when compared to placebo. No statistically significant difference was noted between the two drugs. Neuron destruction was seen only in rabbits receiving either saline (92%) or thiopental (50%).