Clinical feasibility study of protrach dualcare a new speaking valve with heat and moisture exchanger for tracheotomized patients.

Objective: The aim of this study was to evaluate the clinical feasibility of the ProTrach DualCare (Atos Medical, Hörby, Sweden), a device combining a hands-free speaking valve and a Heat and Moisture Exchanger (HME) for tracheotomized patients. Study Design: A non-randomized, prospective single center feasibility study. Methods: Sixteen adult tracheotomized patients were included. Participants were asked to test the DualCare for two weeks while continuing their normal activities. After these two weeks, participants could choose whether or not to take part in the long-term evaluation. The EuroQOL-5D, Borg scale and questionnaires on speaking, pulmonary function and patient preference were used. During the long-term evaluation, a minor redesign was implemented and all participants were asked to test the new device again for one week, with a potential long-term evaluation. Eleven decided to participate. Results: The device was well-tolerated. Speaking noise was reduced (p = 0.020) and speech was considered to sound more natural compared to previously used devices according to the users (p = 0.020). Overall 11 participants preferred the DualCare to their standard device. No serious adverse events were reported. Conclusion: Overall, 11 of 16 participants preferred the DualCare to their standard speaking valve or HME. Users of the DualCare were able to use hands free speech with the benefits of an HME and the device was considered clinically feasible and has the potential to improve quality of life of tracheotomized patients. Level of Evidence: 2b.

Organ-sparing Intensity-modulated radiotherapy for anal cancer using the ACTII schedule: a comparison of conventional and intensity-modulated radiotherapy plans.

AIMS: Conventional external beam radiotherapy for anal cancer is associated with a high rate of treatment-related morbidity. The purpose of this retrospective study was to compare the dosimetric advantages of three intensity-modulated radiotherapy (IMRT) plans with the conventional plan with regards to organs at risk avoidance delivering the ACTII schedule of 50.4 Gy in 1.8 Gy/fraction: 17 fractions for phase 1 and 11 fractions for phase 2. MATERIALS AND METHODS: Ten anal cancer patients (T1-3 N0-3) treated with the conventional plan using four fields and conformal boost were identified. The phase 1 planning target volume (PTV) included tumour, anal canal and inguinal, peri-rectal and internal/external iliac nodes. Phase 2 included identifiable disease only. Three step-and-shoot IMRT plans were generated: IMRT1: phase 1 inverse-planned IMRT with two- to four-field conformal phase 2; IMRT2: both phase 1 and phase 2 inverse-planned IMRT; IMRT3: phase 1 IMRT and phase 2 forward-planned IMRT. All IMRT plans were then compared against the conventional plan on PTV coverage, small bowel, genitalia, femoral heads, bladder and healthy tissue dose volume information. RESULTS: While achieving similar PTV coverage compared with the conventional plan, significant dose reductions were observed for IMRT plans in external genitalia, small bowel and healthy tissue. Reductions were also observed in the femoral heads and bladder. CONCLUSIONS: IMRT significantly reduces the dose to organs at risk while maintaining excellent PTV coverage in anal cancer radiotherapy.

Birth outcomes following treatment for precancerous changes to the cervix: a population-based record linkage study.

OBJECTIVE: To examine whether treatments for precancerous changes to the cervix are associated with adverse birth outcomes in subsequent pregnancies. DESIGN: Population-based retrospective cohort study using electronic linkage of data from the Welsh cervical screening programme and a national routine child health database. SETTING: Wales. POPULATION: A total of 174,325 women aged 20-39 years who received cervical screening between April 2001 and March 2004. METHODS: Logistic regression was used to compare the odds of each birth outcome between women who had negative cervical smears and women who received either colposcopy ± punch biopsy only or colposcopy and excisional or ablative treatments, adjusted for confounding factors (e.g. age, social deprivation and smoking). MAIN OUTCOME MEASURES: Preterm birth (before 37, 32 and 28 weeks of gestation), and low birthweight (<2500 g). RESULTS: Compared with women who had negative cervical smears, the odds ratio for preterm birth (<37 weeks) was significantly increased in women who had colposcopy only (adjusted odds ratio 1.54, 95% CI 1.32-1.80) and single excisional treatment (adjusted odds ratio 1.77, 95% CI 1.47-2.13). Similar results were observed for preterm birth at <32 weeks of gestation. There was no increased risk of preterm birth or low birthweight for women who had treatment compared with women who had colposcopy only. CONCLUSION: Women who were referred for colposcopy had an increased risk of preterm births regardless of whether or not they received treatment to the cervix. This increased risk could be the result of common risk factors for abnormal smears and preterm birth.

An ergonomic evaluation of infant life jackets: Donning time & donning accuracy.

Canada is considering the development of a new standard for infant/child life jackets. Eight currently available (approved and non-approved) infant/child life jackets were procured for evaluation. Fifty-six participants were chosen as a sample of convenience from the general public for testing. The life jackets were divided into two groups of four, which were donned on a soft infant manikin procured from the Red Cross. In 224 attempts at donning, only 43 (19%) attempts resulted in the life jacket being donned correctly in less than 1 min. Only one life jacket came close to a good design and passed the life jacket standard for donning time and accuracy. Failure rates were observed across all the participants irrespective of age, gender, experience with children and experience with recreational marine equipment. Accuracy and speed of donning the life jacket were hampered as the number of donning sub-tasks increased. It was concluded that it is possible to design a life jacket that can be donned correctly in under 1 min. The life jacket must be of simple, intuitive design and fall naturally into the anatomical shape of the child. A minimum number of ties, zips and clips should be used in the design, and if such connectors are used they should be color coded or of different shapes and sizes to avoid confusion.

Use of a patient linked data warehouse to facilitate diabetes trial recruitment from primary care.

Recruitment into clinical trials from primary care may be difficult. Our aim was to use the Secure Anonymised Information Linkage (SAIL) databank to identify potential participants for two factitious trials. We identified 284 and 711 participants for each study (population=250,086). This method appears promising in identifying trial participants.

Quality of 'glottal' stops in tracheoesophageal speakers.

Glottal stops are conveyed by an abrupt constriction at the level of the glottis. Tracheoesophageal (TE) speakers are known to have poor control over the new voice source (neoglottis), and this might influence the production of 'glottal' stops. This study investigated how TE speakers realized 'glottal' stops in abutting words that end and begin with the same vowel. Ten phoneticians rated seven TE speakers' attempts to convey 'glottal' stops less favourably than two laryngeal control speakers' 'glottal' stops. Acoustic analyses showed that TE speakers relied on more gradual changes, but in 25% of realizations, a constriction at the neoglottis, similar to the constriction found in normal speakers, was produced. It was concluded that control over the neoglottis might be greater than is generally assumed. It might be possible to improve TE speakers' awareness and control over the neoglottis through training, using such tools as digital high-speed imaging.

The intelligibility of tracheoesophageal speech, with an emphasis on the voiced-voiceless distinction.

Total laryngectomy has far-reaching effects on vocal tract anatomy and physiology. The preferred method for restoring postlaryngectomy oral communication is prosthetic tracheoesophageal (TE) speech, which like laryngeal speech is pulmonary driven. TE speech quality is better than esophageal or electrolarynx speech quality, but still very deviant from laryngeal speech. For a better understanding of neoglottis physiology and for improving rehabilitation results, study of TE speech intelligibility remains important. Methods used were perceptual evaluation, acoustic analyses, and digital high-speed imaging. First results show large variations between speakers and especially difficulty in producing voiced-voiceless distinction. This paper discusses first results of our experiment.

Compliance, quality of life and quantitative voice quality aspects of hands-free speech.

CONCLUSIONS: With the use of a new automatic stoma valve (ASV) it appears possible to rehabilitate patients who have previously been unsuccessful in acquiring hands-free speech. As well as making daily ASV use possible for an additional group of patients, this new device was also appreciated by many patients as an additional rehabilitation tool for specific occasions. Despite statistically significant improvements in aspects of voice and breathing using this novel ASV, improvement of peristomal adhesion is probably the main factor needed to further increase success rates. Nevertheless, our results show that it makes sense to keep trying to achieve hands-free speech, even if previous attempts have failed. OBJECTIVE: To make a long-term (6 months) assessment of compliance and aspects of voice, breathing and quality of life using a new ASV: the Provox FreeHands heat and moisture exchanger (HME). MATERIAL AND METHODS: This was a prospective clinical multicentre trial in 79 laryngectomized patients (8 regular ASV users, 58 previously unsuccessful users and 13 new users). Data were collected at baseline and after 1 and 6 months by means of European Organization for Research and Treatment of Cancer Quality of Life questionnaires and specific structured questionnaires concerning compliance, skin adhesion, voicing and pulmonary aspects. An objective assessment of voice parameters (maximum phonation time, maximum phonation time while counting, dynamic loudness range and number of pauses in a standard read-aloud text) was made for comparison of different stoma occlusion methods (digital occlusion via an HME and two different ASVs). A subjective assessment of overall voice quality was made. RESULTS: After 6 months, 19% of patients used the new ASV on a daily basis (mean 5 h/day), while 57% used it on an irregular basis as an additional rehabilitation tool for special occasions. Two-thirds of the study group indicated that they would continue to use the new ASV after the study period. With respect to the objective parameters, statistically significantly better maximum phonation times and dynamic loudness ranges were observed with the new ASV compared to the Blom-Singer ASV. However, the best results for all the objective parameters were obtained with digital occlusion via the Provox HME.

How much did cold shock and swimming failure contribute to drowning deaths in the fishing industry in British Columbia 1976-2002?

BACKGROUND: The Workers' Compensation Board of British Columbia requested a retrospective analysis of all fishermen's deaths from immersion in water in British Columbia. AIMS: To identify the underlying cause of drowning and make recommendations to improve safety in the fishing industry. METHOD: Eighty-nine inshore and offshore fishing accidents were analysed. Where possible, deaths were classified into the four stages of cold-water immersion: cold shock, swimming failure, hypothermia and post-rescue collapse. Other factors that led up to the drowning were also identified. RESULTS: One hundred and thirty fishermen died from immersion between 1976 and 2002. One hundred and twenty-eight drownings were certified by the coroner as drowning or drowning/hypothermia and two were certified as cardiac event after immersion. The underlying causes of drownings were reclassified as: cold shock (5.4%), swimming failure (5.4%), hypothermia (5.4%), post-rescue collapse (0.8%), cardiac event (0.8%) and drowning/other (10%). In the remaining 72.2% of deaths, there was insufficient information to determine an underlying cause. All deaths occurred in water below 17.5 degrees C but 95% were in water less than 15 degrees C. CONCLUSIONS: Immersion in water below 15 degrees C is dangerous and this should be emphasized on marine survival courses. Accident investigators, coroners and pathologists need a common checklist to record vital data. A recommended format is included as Supplementary data available at Occupational Medicine Online. Fishermen should be educated about the dangers of sudden, unexpected immersion in cold water. Consideration should be given to making marine survival courses mandatory for fishermen.

Fractalkine expression on human renal tubular epithelial cells: potential role in mononuclear cell adhesion.

Fractalkine (CX3CL1) is a transmembrane molecule with a CX3C chemokine domain attached to an extracellular mucin stalk which can induce both adhesion and migration of leucocytes. Mononuclear cell infiltration at renal tubular sites and associated tubular epithelial cell damage are key events during acute renal inflammation following renal allograft transplantation. Using northern and Western blot analysis, we have demonstrated the expression of fractalkine message and protein by renal tubular epithelial cells in vitro. The expression was up-regulated by TNF-alpha, a key proinflammatory cytokine in acute rejection. Investigation of surface expression of fractalkine on cultured proximal tubular epithelial cells revealed only a subpopulation of positively staining cells. Immunohistochemistry revealed that only a proportion of tubules in renal allograft biopsies showed induction of fractalkine expression. Studies using a static model of adhesion demonstrated CX3CR1/fractalkine interactions accounted for 26% of monocytic THP-1 cell and 17% of peripheral blood natural killer cell adhesion to tubular epithelial cells, suggesting that fractalkine may have a functional role in leucocyte adhesion and retention, at selected tubular sites in acute renal inflammation. Thus, fractalkine blockade strategies could reduce mononuclear cell mediated tubular damage and improve graft survival following kidney transplantation.

Breath-holding ability of offshore workers inadequate to ensure escape from ditched helicopters.

BACKGROUND: Following a helicopter ditching in water, the survival rate of individuals not mortally injured by the impact ranges from 50-85%. One possible cause for this low survival rate is that the crew and passengers cannot hold their breath underwater long enough to make the often difficult escape from an inverted and submerged helicopter. METHODS: We investigated pulmonary function, breath-holding times in air (BHTa) and water (BHTw) of 228 students enrolled in offshore survival courses required to work in either the offshore petroleum industry or in military marine aviation. Comparisons were performed based on occupation, SCUBA experience, and smoking. RESULTS: In 25 degrees C pool water, the overall BHTw ranged from 5.4 to 120 s with a median of 37 s. Of the 228 subjects, 34% had a BHTw less than the 28 s required for the complete evacuation of a Super Puma helicopter under ideal conditions. No significant differences in BHTw were observed based on either smoking history (Non-Smoker, 41.5 +/- 21.6 s; Smoker, 37.2 +/- 20.2 s) or occupation (Novice, 37.5 +/- 21.1 s; Offshore, 40.5 +/- 21.1 s; Military, 45.2 +/- 20.9 s). However, SCUBA-trained individuals had a significantly longer BHT, (47.4 +/- 21.6 s) than non-SCUBA (37.6 +/- 20.6 s), as well as a greater force vital capacity (FVC), BHTa, and subjective comfort in water. CONCLUSIONS: It is concluded that the inability to breath-hold in emergency situations is a major contributor to the low survival rates of marine helicopter ditchings. Therefore, efforts must be made to both decrease escape times and to increase survival time underwater.

The basis for the development of a fuselage evacuation time for a ditched helicopter.

HYPOTHESIS: When a helicopter ditches or crashes in water, unless the buoyancy bags are inflated, it commonly sinks inverted. Thus, crew and passengers must make an underwater escape. It is postulated that later passengers in the escape sequence do not have the breath-holding ability to conduct a successful escape, particularly if the water is cold. This contributes to the 20-50% mortality rate in survivable accidents. METHODS: There were 132 immersed subject evaluations which were conducted in daylight and darkness to measure escape times from a helicopter underwater escape trainer, configured to the Super Puma, seated for 15 and 18 passengers. The subjects were highly experienced instructors or Navy clearance divers. RESULTS: The time from when each subject's head disappeared underwater until each subject surfaced and total fuselage evacuation time were measured and any problems hampering escape were noted. Breath-holding for the last subject out ranged from 28 to 92 s. An emergency breathing system was used by a minimum of four subjects each time and a maximum of 11 subjects in one condition. The buoyancy of the survival suit was the principal component that hampered escape. CONCLUSION: Breath-holding times were too long for the later subjects to escape without resorting to an EBS, in spite of the fact that they were highly trained. For regular crew and passengers flying over water, this would explain the high mortality, etc. Therefore, a new helicopter standard should be developed requiring fuselage design to accommodate total evacuation within 20 s from underwater. For current helicopters, where this cannot be achieved, passengers should be provided with some form of air supply, or, after ditching, the helicopter should be modified so that it will stay afloat on its side and retain an air space in the cabin.

Underwater disorientation as induced by two helicopter ditching devices.

BACKGROUND: Spatial orientation is based on the integration of concordant and redundant information from the visual, vestibular, and somatosensory systems. When a person is submerged underwater, somatosensory cues are reduced, and vestibular cues are ambiguous with respect to upright or inverted position. Visual cues may be lost as a result of reduced ambient light. Underwater disorientation has been cited as one of the major factors that could inhibit emergency egress after a helicopter ditching into water. One countermeasure to familiarize aircrew with underwater disorientation is emergency egress training. This study examined the relative degree of underwater disorientation induced by the Modular Egress Training Simulator (METS) and the Shallow Water Egress Trainer (SWET). METHODS: There were 36 healthy subjects (28 males and 8 females) who participated in the study. Underwater disorientation was quantified by measuring the deviation of subjective vertical-pointing from the gravitational vertical, time to egress, and subjective reports of disorientation and ease of egress. A repeated measure design was employed with seat position (SWET chair, METS window, and METS aisle) as the sole factor. RESULTS: Subjective response data indicated that the degree of disorientation is rated significantly higher, and the ease of egress is rated worse from the two METS seat positions than from the SWET. This is supported by the findings that subjective vertical-pointing accuracy is worse in the METS seat positions than in the SWET (p < 0.01). The time to egress is longer from the two METS seat positions than from SWET (p < 0.01). CONCLUSION: Our results indicate that the METS device is effective for inducing underwater disorientation as provoked by simulated helicopter ditching. disorientation, vestibular, subjective pointing.

Cholesterol oxidase: sources, physical properties and analytical applications.

Since Flegg (H.M. Flegg, An investigation of the determination of serum cholesterol by an enzymatic method, Ann. Clin. Biochem. 10 (1973) 79-84) and Richmond (W. Richmond, The development of an enzymatic technique for the assay of cholesterol in biological fluids, Scand. J. clin. Lab. Invest. 29 (1972) 25; W. Richmond, Preparation and properties of a bacterial cholesterol oxidase from Nocardia sp. and its application to enzyme assay of total cholesterol in serum, Clinical Chemistry 19 (1973) 1350-1356) first illustrated the suitability of cholesterol oxidase (COD) for the analysis of serum cholesterol, COD has risen to become the most widely used enzyme in clinical laboratories with the exception of glucose oxidase (GOD). The use is widespread because assays incorporating the enzyme are extremely simple, specific, and highly sensitive and thus offer distinct advantages over the Liebermann-Burchard analytical methodologies which employ corrosive reagents and can be prone to unreliable results due to interfering substances such as bilirubin. Individuals can now readily determine their own serum cholesterol levels with a simple disposable test kit. This review discusses COD in some detail and includes the topics: (1) The variety of bacterial sources available; (2) The various extraction/purification protocols utilised in order to obtain protein of sufficient clarification (purity) for use in food/clinical analysis; (3) Significant differences in the properties of the individual enzymes; (4) Substrate specificities of the various enzymes; (5) Examples of biological assays which have employed cholesterol oxidase as an integral part of the analysis, and the various assay protocols; (6) New steroidal products of COD. This review is not a comprehensive description of published work, but is intended to provide an account of recent and current research, and should promote further interest in the application of enzymes to analytical selectivity.

Repellent and antifeedant activity of salicylic acid and related compounds against the biting midge, Culicoides impunctatus (Diptera: Ceratopogonidae).

An artificial membrane, blood-feeding method was used to assess the repellent and antifeedant effects of derivatives of salicylic acid on the biting midge Culicoides impunctatus Goetghebeur. Trans-2-hydroxycyclohexanecarboxylic acid, 6-methylsalicylic acid, 2,6-dihydroxy-4-methylbenzoic acid, and salicyluric acid caused highly significant inhibition of feeding, with salicyluric acid performing significantly greater than the other compounds. Investigating the effects of alkyl substitution of salicylic acid, o-thymotic and o-cresotic acids were also effective. A pilot clinical trial using salicyluric acid indicated that it provided a protective effect and it was hypothesized that this may have resulted primarily from contact, because no significant repellent effects were shown for this compound in a microscope slide test, designed to demonstrate repellency with volatile compounds.

Evaluation of a new universal jettison mechanism for helicopter underwater escape.

BACKGROUND: To date, there is no standard jettison mechanism for doors, windows, or hatches in ditched helicopters. A new Universal Escape Exit (UEE) has been invented and the performance has been compared with two current in-service systems in a helicopter underwater escape trainer. METHOD: A total of 416 evacuations were conducted by 40 subjects in two experiments using the Survival Systems Limited's underwater escape trainer. RESULTS: The UEE had a distinct 2-s advantage to escape; and, in the majority of cases, was preferred to a rotating lever or a straight push out system. CONCLUSIONS: Further work should continue with UEE development for qualification in an operational helicopter.

Interleukin-8: A pathogenetic role in antineutrophil cytoplasmic autoantibody-associated glomerulonephritis.

BACKGROUND: In neutrophil trafficking, the role of interleukin-8 (IL-8) is location dependent. Tissue IL-8 directs transmigration, whereas intravascular IL-8 frustrates this process. The bystander damage of glomerular endothelium by antineutrophil cytoplasmic autoantibody (ANCA)-activated neutrophils is believed to be an early event in the pathogenesis of ANCA-associated glomerulonephritis. We have studied the role of IL-8 in this process. METHODS: Intraglomerular expression of IL-8 in patients with ANCA-associated glomerulonephritis was studied by in situ hybridization and immunohistochemistry and location of neutrophils by serial section immunohistochemistry. In vitro, we analyzed ANCA-stimulated neutrophil IL-8 production by enzyme-linked immunosorbent assay, and the IL-8 attributable effect of ANCA-stimulated neutrophil supernatant by chemotactic and transendothelial assays. RESULTS: There was intraglomerular expression of IL-8 at segmental, crescentic, and parietal epithelial sites. IL-8 protein expression colocalized to intraglomerular neutrophils; many localized within glomerular capillary loops, suggesting failed trafficking to tissue IL-8. ANCAs differentially stimulated time- and dose-dependent neutrophil IL-8 production, and ANCA-stimulated neutrophil supernatant demonstrated potent IL-8-dependent chemotactic activity and inhibited transendothelial migration of normal human neutrophils toward an IL-8 gradient. CONCLUSION: Despite heavy tissue expression of IL-8 in ANCA-associated GN, the production of IL-8 by ANCA-stimulated neutrophils within the intravascular compartment may frustrate neutrophil transmigration, encourage intravascular stasis, and contribute to bystander damage of glomerular endothelial cells.

The effect of wave motion on dry suit insulation and the responses to cold water immersion.

METHODS: Six subjects who were each wearing a dry immersion suit system were immersed for 1 h in 16 degrees C water in a number of different wave conditions, ranging from still water to 70 cm in height. Physiological and physical parameters were measured in order to calculate the total thermal resistance of the suit system and its components. RESULTS: None of the physiological parameters were affected significantly by the wave conditions, except for skin heat flux, which increased with wave height from 72.0 +/- 1.9 W x m(-2), at 0 cm of height, to 85.5 +/- 2.9 W x m(-2), at 70 cm of height. Wave heights up to 70 cm decreased the insulation (including boundary layer) of the dry suit system by 14%, and the only component of the suit affected by the wave motion was the insulation of the water boundary layer, which decreased by 75%. The body sites that were most affected by wave motion were the head and the trunk, with an average 45% decrement in suit system thermal resistance at those sites at wave heights of 0 to 70 cm. No significant effect was observed at sites on the distal limbs. CONCLUSION: To simulate open ocean conditions in the laboratory, the standards must take the reduction of suit insulation into account.

Options for liferaft entry after helicopter ditching.

METHOD: Dry and wet evacuations were conducted by 24 male and 19 female subjects from the Nutec Super Puma Simulator into two different types of aviation liferaft. RESULTS: Dry evacuation on the windward side is the method of choice. The non-canopy raft is subjectively and objectively easier to enter both from the helicopter and the sea. CONCLUSIONS: The non-canopy raft is the raft of choice, the canopy raft needs a redesign to ensure that it always inflates the correct way and both rafts need a redesign of the painter anchor point. Aircrew should have special training in open water after traditional pool training. A helicopter ditching survival compass has been developed for training all who fly over water for a living.