Expert range maps of global mammal distributions harmonised to three taxonomic authorities

AIM

Comprehensive, global information on species' occurrences is an essential biodiversity variable and central to a range of applications in ecology, evolution, biogeography and conservation. Expert range maps often represent a species' only available distributional information and play an increasing role in conservation assessments and macroecology. We provide global range maps for the native ranges of all extant mammal species harmonised to the taxonomy of the Mammal Diversity Database (MDD) mobilised from two sources, the Handbook of the Mammals of the World (HMW) and the Illustrated Checklist of the Mammals of the World (CMW).

LOCATION

Global.

TAXON

All extant mammal species.

METHODS

Range maps were digitally interpreted, georeferenced, error-checked and subsequently taxonomically aligned between the HMW (6253 species), the CMW (6431 species) and the MDD taxonomies (6362 species).

RESULTS

Range maps can be evaluated and visualised in an online map browser at Map of Life (mol.org) and accessed for individual or batch download for non-commercial use.

MAIN CONCLUSION

Expert maps of species' global distributions are limited in their spatial detail and temporal specificity, but form a useful basis for broad-scale characterizations and model-based integration with other data. We provide georeferenced range maps for the native ranges of all extant mammal species as shapefiles, with species-level metadata and source information packaged together in geodatabase format. Across the three taxonomic sources our maps entail, there are 1784 taxonomic name differences compared to the maps currently available on the IUCN Red List website. The expert maps provided here are harmonised to the MDD taxonomic authority and linked to a community of online tools that will enable transparent future updates and version control.

Effectiveness of dogs for detecting feral cat scats in wheatbelt reserves of Western Australia

Abstract ContextDogs are increasingly being used in conservation work to collect information on species abundance, distribution, occupancy and other biological measures. Monitoring feral cats through the use of detection dogs could provide a useful technique to complement existing feral cat survey and control methods. AimTo demonstrate and quantify the ability of trained detection dogs to reliably and efficiently detect feral cat scats when present in woodland conservation reserves in the Wheatbelt of Western Australia. MethodsCat scats were randomly placed into 466 1.5 ha (150 m × 100 m) quadrats in Tutanning Nature Reserve, Western Australia, and the location of the scat was recorded. Quadrats were then independently searched by dogs walking a central transect line and the locations of all scats detected were recorded, with the distance from the scat to the transect subsequently being calculated. Data collected allowed the relationship between distance from the transect and detection probability to be used to assist modelling of detection probabilities. Key resultsDogs detected scats in 213 (55%) of 384 quadrats that were searched using a single transect line method. All indications of a find by the detector dogs were associated with a cat scat (no false indications). Detection probabilities for scats declined with distance from the transect line and with an increasing age of the scat. Simulations to investigate management options for cat control programs quantified effort required to detect cat scats under varying densities. ConclusionDogs were highly efficient at detecting scats within the woodland environment of the Western Australian wheatbelt. The effort required to detect a scat was considerably higher when cat density was low. ImplicationsOn the basis of the detection probabilities derived from the present study, trained scat-detection dogs can be expected to efficiently search woodlands and find cat scats by using an effective sweep width of 100 m (50 m either side of a transect) when scats are fresh. Sweep widths need to be reduced significantly if it is important to locate scats that have been exposed to the elements for greater periods of time, or to search habitats where terrain and vegetation cover are more challenging.

Are red-tailed phascogales (Phascogale calura) at risk from Eradicat® cat baits?

Abstract ContextFeral cats have benefitted from effective control of foxes in south-western Australia and, consequently, their impact on some threatened mammal species has increased. Control of feral cats in the region can be enhanced by use of the Eradicat® cat bait, but its impact on non-target animal populations requires investigation before widespread use. AimsThe aim of the present study was to determine through field trials whether consumption of Eradicat® baits by resident red-tailed phascogales, following a broadscale baiting operation to control feral cats, was sufficiently frequent to cause significant rates of mortality in wild populations of phascogales. MethodsNine radio-tagged red-tailed phascogales were monitored through an Eradicat® baiting event to determine their survival. Removal and consumption of toxic and non-toxic rhodamine B-labelled baits by a range of species were monitored with camera traps and by subsequent trapping of red-tailed phascogales and other mammals to sample whiskers for evidence of rhodamine uptake. Key resultsAlthough some phascogales showed interest in baits and sometimes moved them from the deposition site, all radio-tagged phascogales survived for at least 1 week after baiting, by which time very few or no baits remained. Examination of whiskers sampled from individuals exposed to rhodamine-labelled baits showed that consumption of non-toxic Eradicat® baits by phascogales was negligible; only one phascogale of 62 sampled showed any rhodamine banding. ConclusionsThe present study provided no evidence that red-tailed phascogales in the study region are at risk from an Eradicat® baiting episode in autumn. ImplicationsThe risk to red-tailed phascogale populations through the use of Eradicat® baiting to control cats in their habitat in the Great Southern region of Western Australia is likely to be low. Further research to elucidate any impact of repeated baiting on populations of this species at several locations is recommended.

Sequence analyses at mitochondrial and nuclear loci reveal a novel Theileria sp. and aid in the phylogenetic resolution of piroplasms from Australian marsupials and ticks

The order Piroplasmida encompasses two main families: Babesiidae and Theileriidae, containing tick-borne pathogens of veterinary and medical importance worldwide. While only three genera (Babesia, Cytauxzoon and Theileria) comprising piroplasm parasites are currently recognised, phylogenetic studies at the 18S rRNA (18S) gene suggest that these organisms represent at least ten lineages, one of which comprises the relatively unique and highly diverse Theileria spp. from Australian marsupials and ticks. As an alternative to analysing 18S sequences alone, sequencing of mitochondrial genes has proven to be useful for the elucidation of evolutionary relationships amongst some groups of piroplasms. This research aimed to characterise piroplasms from Australian native mammals and ticks using multiple genetic markers (18S, cytochrome c, oxidase subunit III (cox3) and cytochrome B (cytB)) and microscopy. For this, nearly complete piroplasm-18S sequences were obtained from 32 animals belonging to six marsupial species: eastern bettong (Bettongia gaimardi), eastern quoll (Dasyurus viverrinus), eastern grey kangaroo (Macropus giganteus), swamp wallaby (Wallabia bicolor), quokka (Setonix brachyurus) and Gilbert’s potoroo (Potorous gilbertii). The organisms detected represented eight novel Theileria genotypes, which formed five sub-clades within the main marsupial clade containing previously reported Australian marsupial and tick-derived Theileria spp. A selection of both novel and previously described Australian piroplasms at the 18S were also successfully characterised, for the first time, at the cox3 and cytB loci, and corroborated the position of Australian native theilerias in a separate, well-supported clade. Analyses of the cox3 and cytB genes also aided in the taxonomic resolution within the clade of Australian Piroplasmida. Importantly, microscopy and molecular analysis at multiple loci led to the discovery of a unique piroplasm species that clustered with the Australian marsupial theilerias, for which we propose the name Theileria lupei n. sp.

Potential impacts of poison baiting for introduced house mice on native animals on islands in Jurien Bay, Western Australia

Context House mice (Mus domesticus) are present on Boullanger and Whitlock islands, Western Australia, and could potentially threaten populations of the dibbler (Parantechinus apicalis) and grey-bellied dunnart (Sminthopsis griseoventer) through competition for resources. A workshop in 2007 recommended a study to assess the feasibility of eradicating house mice from the islands by using poison baits and of the risk posed to non-target native species. Aim We aimed to assess the risk to non-target native species if poison baiting was used to eradicate house mice on Boullanger and Whitlock islands. Methods Non-toxic baits containing the bait marker rhodamine B were distributed on Boullanger Island and on the mouse free Escape Island to determine the potential for primary poisoning. Acceptance of baits by mammals was measured through sampling and analysis of whiskers, and by reptiles through observations of dye in faeces. To determine the potential for secondary exposure to poison, the response of dibblers to mouse carcasses was observed using motion-activated cameras. Bait acceptance was compared using two methods of delivery, namely, scattering in the open and delivery in polyvinyl chloride (PVC) tubes. A cafeteria experiment of bait consumption by dibblers was also undertaken using captive animals held at the Perth Zoo. Ten dibblers were offered non-toxic baits containing rhodamine B in addition to their normal meals; consumption of bait and the presence of dye in whiskers were measured. Key results Bait acceptance on the islands was high for house mice (92% of individuals) and dibblers (48%) and it was independent of bait-delivery technique. There was no evidence of bait acceptance by grey-bellied dunnarts. Dibblers may consume mice carcasses if available; however, no direct consumption of mice carcasses was observed with movement sensor cameras but one dibbler was observed removing a mouse carcass and taking it away. During the cafeteria experiment, 9 of 10 captive dibblers consumed baits. Conclusions This investigation demonstrated that dibblers consume baits readily and island populations would experience high mortality if exposed to poison baits. Poison baiting could effectively eradicate mice from Boullanger and Whitlock islands but not without mortality for dibblers. Implications Toxic baits could be used to eradicate mice from Boullanger and Whitlock islands, provided that non-target species such as dibblers were temporarily removed from the islands before the application of baits.

The innate resistance of Trypanosoma copemani to human serum

Trypanosoma copemani is known to be infective to a variety of Australian marsupials. Characterisation of this parasite revealed the presence of stercorarian-like life-cycle stages in culture, which are similar to T. rangeli and T. cruzi. The blood incubation infectivity test (BIIT) was adapted and used to determine if T. copemani, like T. cruzi and T. rangeli, has the potential to grow in the presence of human serum. To eliminate any effects of anticoagulants on the complement system and on human high density lipoprotein (HDL), only fresh whole human blood was used. Trypanosoma copemani was observed by microscopy in all human blood cultures from day 5 to day 19 post inoculation (PI). The mechanism for normal human serum (NHS) resistance in T. copemani is not known. The results of this study show that at least one native Australian trypanosome species may have the potential to be infective for humans.

Numbat nirvana: conservation ecology of the endangered numbat (Myrmecobius fasciatus) (Marsupialia : Myrmecobiidae) reintroduced to Scotia and Yookamurra Sanctuaries, Australia

Despite a vigorous reintroduction program between 1985 and 2010, numbat populations in Western Australia are either static or declining. This study aimed to document the population ecology of numbats at two sites that are going against this trend: Scotia Sanctuary in far western New South Wales and Yookamurra Sanctuary in the riverland of South Australia. Scotia (64 659 ha) and Yookamurra (5026 ha) are conservation reserves owned and managed by the Australian Wildlife Conservancy and where numbats were reintroduced in 1999 and 1993 respectively. Both sites have large conservation-fence-protected introduced-species-free areas where there are no cats (Felis catus) or red foxes (Vulpes vulpes). Numbats were sourced from both wild and captive populations. From small founder populations, the Scotia numbats are now estimated to number 169 (113–225) with 44 at Yookamurra. Radio-collared individuals at Scotia were active between 13 and 31°C. Females had home ranges of 28.3 ± 6.8 ha and males 96.6 ± 18.2 ha, which leads to an estimated sustainable population or carrying capacity of 413–502 at Scotia. Captive-bred animals from Perth Zoo had a high mortality rate upon reintroduction at Scotia due to predation by raptors and starvation. The habitat preferences for mallee with a shrub understorey appear to be driven by availability of termites, and other reintroduced ecosystem engineers appear to have been facilitators by creating new refuge burrows for numbats. This study shows that numbats can be successfully reintroduced into areas of their former range if protected from introduced predators, and illustrates the difficulties in monitoring such cryptic species.

Further characterisation of two Eimeria species (Eimeria quokka and Eimeria setonicis) in quokkas (Setonix brachyurus)

The identification and characterisation of novel Eimeria species has largely been based on sporulated oocyst and sporocyst morphology, the host species and the geographical range. Variation in the size and shape of Eimeria oocysts across their host range however, make the identification and characterisation of novel species using traditional methodologies alone problematic. The use of molecular markers and phylogenetic analysis has greatly advanced our ability to characterise Eimeria species and has recently been applied to understand evolutionary relationships among Eimeria species from Australian marsupials. In the present study, Eimeria species isolated from quokkas (Setonix brachyurus) captured from Two Peoples Bay, Bald Island and Rottnest Island, Western Australia, were morphologically identified as Eimeria quokka and Eimeria setonicis. Both Eimeria species were identified as being polymorphic in nature with regards to sporulated oocyst and sporocyst morphometrics. Phylogenetic analysis using 18S rRNA and COI (cytochrome c oxidase subunit 1) genes, grouped E. quokka and E. setonicis within the Eimeria marsupial clade together with Eimeria trichosuri from brushtail possums, Eimeria macropodis from tammar wallabies (Macropus eugenii) and several unidentified macropod Eimeria species from western grey kangaroos (Macropus fuliginosus). This study is the first to characterise E. quokka and E. setonicis by molecular analysis, enabling more extensive resolution of evolutionary relationships among marsupial-derived Eimeria species.

Cutaneous papillomatosis and carcinomatosis in the Western barred bandicoot (Perameles bougainville)

A progressive wart-like syndrome in both captive and wild populations of the Western barred bandicoot (WBB) is hindering conservation efforts to prevent the extinction of this endangered marsupial. In this study, 42 WBBs exhibiting the papillomatosis and carcinomatosis syndrome were examined. The disease was characterized by multicentric proliferative lesions involving cutaneous and mucosal surfaces, which were seen clinically to increase in size with time. Grossly and histologically the smaller skin lesions resembled papillomas, whereas the larger lesions were most commonly observed to be squamous cell carcinomas. Large amphophilic intranuclear inclusion bodies were observed in hyperplastic conjunctival lesions of 8 WBBs under light microscopy. Conjunctival lesions from 2 WBBs examined using transmission electron microscopy contained a crystalline array of spherical electron-dense particles of 45-nm diameter, within the nucleus of conjunctival epithelial cells, consistent with a papillomavirus or polyomavirus. Conjunctival samples from 3 bandicoots that contained intranuclear inclusion bodies also demonstrated a positive immunohistochemical reaction after indirect immunohistochemistry for papillomavirus structural antigens. Ultrastructural and/or immunohistochemical evidence of an etiologic agent was not identified in the nonconjunctival lesions examined. Here we describe the gross, histopathologic, ultrastructural, and immunohistochemical findings of a papillomatosis and carcinomatosis syndrome recently identified in the WBB.

Klossiella quimrensis (Apicomplexa: Klossiellidae) causes renal coccidiosis in western barred bandicoots Perameles bougainville (Marsupialia: Peramelidae) in Western Australia

Previous studies have described a range of Klossiella species parasitic in marsupial hosts. Klossiella quimrensis is the etiologic agent of renal coccidiosis in the peramelid marsupial hosts Isoodon obesulus and Perameles gunnii in Eastern Australia, but there is no previous report of klossiellosis in Western Australian peramelids. This study describes klossiellosis diagnosed by histology of renal tissue sections collected during necropsy of 20 Perameles bougainville between 2000 and 2005. Sporonts, sporoblasts, and macrogametes were identified within parasitophorous vacuoles of epithelial cells located near the renal corticomedullary junction. The prevalence of renal coccidiosis in P. bougainville diagnosed by renal histology is estimated at 30%. Only a single unsporulated sporocyst was detected by examination of cystocentesis-collected urine, indicating that microscopic evaluation of urine samples is an insensitive diagnostic test for detection of K. quimrensis in P. bougainville. This infection in P. bougainville is indirectly associated with mild multifocal interstitial lymphohistiocytic nephritis and is likely to be only minimally pathogenic in otherwise healthy individuals. Our study also extends the host and geographic range of K. quimrensis to include P. bougainville and Western Australia.

A quantitative dietary study of the ?Critically Endangered? Gilbert?s potoroo Potorous gilbertii

Faecal analysis from the only known population of Gilbert?s potoroo (Potorous gilbertii) near Albany, Western Australia revealed that it, like other rat-kangaroo species is primarily mycophagous. Diet was determined by faecal collections from live-captured animals within Two Peoples Bay Nature Reserve. Microscopic examination of samples collected from June - September 2000 and additional samples from storage, found fungi to comprise over 90% of faecal matter. A total of 44 fungal spore types were identified with many believed to be of hypogeous origin. Fungal spores belonging to the genera Mesophellia, Elaphomyces, Hysterangium and an unknown spore type (Unknown 1) were frequently recorded in samples. Non-fungal material including plants (stems, roots and seeds) and invertebrates represented the remainder. This investigation found that P. gilbertii fed almost exclusively on fungi and could be considered a specialised mycophagist.

Cryptosporidium muris infection in bilbies (Macrotis lagotis)

Cryptosporidiosis is an enteric disease of animals and humans that can be fatal in immunocompromised individuals. There is no known effective treatment for cryptosporidiosis. Bilbies are threatened marsupials and are bred in captivity as part of a recovery program to re-introduce this species to the southwest of Western Australia. Cryptosporidium muris infection was detected in the faeces of bilbies at a captive breeding colony. Stress associated with a high density of bilbies in enclosures may have predisposed some of the bilbies to infection with C. muris. C. muris has been described in mice and was found in the faeces of one mouse trapped in the breeding enclosures. It is likely the bilbies acquired the infection from mice by faecal contamination of food and water. The infection cleared within 2 months from some bilbies, however others remained infected for 6 months and treatment was attempted with dimetridazole. Subsequently the parasite was no longer be detectable in the faeces.

Patient weighting of importance of asthma symptoms

BACKGROUND

Quality of life measures are increasingly important in evaluating outcomes in asthma. If some asthma symptoms are more troublesome to patients than others, this may affect their contribution to outcome measures. This study was designed to assess the relative importance of common symptoms in adults with asthma.

METHODS

A postal survey using conjoint analysis was performed in 272 adults attending hospital outpatient clinics with moderately severe asthma. Patients were asked to chose between "symptom scenarios" offering different combinations of levels of five common asthma symptoms over one week. Two versions of the questionnaire were used with identical scenarios presenting symptoms in different orders. Different patients answered the two versions. Regression analysis was used to calculate symptom weights for daytime cough, breathlessness, wheeze and chest tightness, and sleep disturbance.

RESULTS

Symptom order, percentage predicted peak expiratory flow (PEF), and symptoms in the week before the survey did not influence the choice of scenario. In both questionnaires patients were more likely to choose scenarios with low levels of cough and breathlessness than low sleep disturbance, wheeze or chest tightness. Regression weights for cough (-0.52) and breathlessness (-0.49) were twice those of wheeze (-0.25), chest tightness (-0.27), and sleep disturbance (-0.25). For 12% of patients cough dominated patient preferences, regardless of all other symptoms. Age was inversely related to weight given by patients to breathlessness.

CONCLUSIONS

The prominence of cough among other asthma symptoms was unexpected. Daytime cough and breathlessness had greater impact for patients than wheeze or sleep disturbance. Age influenced symptom burden, with younger patients giving greater weight to breathlessness than older patients. Conjoint analysis appears to be a useful method for establishing the relative importance of common symptoms.

Symptoms, quality of life, and health service contact among young adults with mild asthma

This report assesses Quality of Life (QoL) and its relationship to current symptoms and prospective medical contact among 396 adult patients with asthma. Patients were 16 to 52 yr of age and in the care of family physicians in the northeast of Scotland. All patients had been prescribed asthma medication within the previous 3 mo. Mean %pred FEV(1) was 87.4, mean %pred PEF was 85.1; 41% reported respiratory symptoms every week in the month before interview. Patients completed the SF-36, SF-12, and St. George's Respiratory Questionnaire (SGRQ) scales. Although mean scores on the SF-36 and SF-12 were close to population norms for patients without chronic illness, the presence of any respiratory symptoms in the month before interview was related to significantly lower QoL scores on the SF-36 scales of Physical Functioning, Energy, Mental Health, Pain, and Health Perception: the SF-12 Physical Functioning scale, and the SGRQ Symptoms, Impact and Activities scales. Physician contact for asthma in the 12 mo after interview was significantly related to SF-36, SF-12, and SGRQ scores at time of interview; however, when adjusted for symptoms at time of interview, only the SGRQ scales remained significant predictors of prospective physician contact. We conclude that respiratory symptoms have significant impact on QoL among patients with mild asthma, measured by generic and respiratory QoL scales, but that a specific respiratory scale is better able to discriminate patients who will seek physician care for asthma.

Mitochondrial DNA sequence variation within the remnant populations of the endangered numbat (Marsupialia: Myrmecobiidae: Myrmecobius fasciatus)

The numbat has been reduced to two populations in Western Australia. To better understand the effects of range reduction on gene flow and genetic variation, and to address questions crucial for the species' management, we analysed mitochondrial DNA (mtDNA) sequences of free-ranging individuals and museum specimens. The results suggest recent connectivity between the remnant populations, although one of those may have lost significant amounts of genetic diversity during the recent population size reduction. We propose that for management purposes the remnant populations should be treated as a single historical lineage and that, subject to certain caveats, consideration should be given to population augmentation by translocation.

Requests for repeat medication prescriptions and frequency of acute episodes in asthma patients

This study was conducted to determine if suboptimal use of inhaled steroid and over-reliance on bronchodilator medication to control asthma symptoms is associated with higher risk of acute asthma episodes. Details of repeat prescriptions for medication and use of health services over 12 months were collected for 754 adult outpatients with asthma; all were prescribed inhaled corticosteroid. Patients who requested less than five prescriptions per year were considered suboptimal users. Patients who requested seven or more bronchodilator prescriptions and less than five inhaled steroid prescriptions had significantly more family physician consultations for asthma episodes (p < 0.05), more hospital admissions (p < 0.05), and more disturbed nights in the week before hospital or family physician review (p < 0.05). Some patients with more severe asthma put themselves at risk by relying on bronchodilator medication rather than regular inhaled steroid for asthma control. Among patients who were low bronchodilator users, those who requested few inhaled steroid prescriptions were younger and more anxious but did not have an increased risk of acute asthma episodes.

Asthma, wheezy bronchitis, and atopy across two generations

Although the prevalence of asthma has risen significantly during the last 30 yr, it is not clear whether this has occurred primarily in persons with a strong genetic predisposition to asthma and atopy or in other sections of the population. We have investigated outcomes in children of nuclear families selected through probands previously characterized by studies in 1964 and 1989 as having histories of persistent childhood onset atopic asthma, transient childhood wheezy bronchitis, and no respiratory symptoms or atopy. Children of wheezy bronchitic probands had a significantly better symptomatic outcome in adolescence, irrespective of the atopic status of the parent proband, than do children of either asthmatic or asymptomatic probands, suggesting that this may be a syndrome that shows familial aggregation and is distinct from asthma. Total serum IgE levels were significantly lower in children of nonatopic asymptomatic probands, including those with wheezing symptoms. In contrast children of nonatopic asymptomatic probands had an unexpectedly high prevalence of wheezing (33%), positive skin prick tests (56%), and positive specific serum IgE to common allergens (48%) that was similar to that found in children of atopic asthmatic probands. Our findings support the concept that wheezy bronchitis is a separate syndrome from atopic asthma. High total serum IgE levels within our population appear to be an important marker of genetic predisposition to atopy. Our data also suggest that much of the increase in asthma prevalence is associated with specific IgE sensitization and is occurring in persons previously considered to be at low risk of developing asthma or atopy.

Domiciliary nebuliser therapy--a valuable option in chronic asthma and chronic obstructive pulmonary disease?

Domiciliary nebulisers are in widespread use for patients who have severe chronic airways disease, both asthma and chronic obstructive pulmonary disease (COPD). We report a study of the use of domiciliary nebulisers designed to assess practical problems and the value of such therapy in preventing hospital admissions. A total of 405 patients underwent a structured interview at home and their case records were reviewed. Technical performance of the nebuliser compressors was assessed. The mean (SD) age of those interviewed was 64.5 (12) years. 185 patients had a physician diagnosis of asthma, and 208 had COPD. 87% patients used their nebuliser at least once daily. Side effects, reported by 54%, were related to frequency of use and commoner in younger patients. 29 subjects (7%) died within 2 years of receiving their nebuliser. Among the survivors, the 2 year periods before and after supply of the nebuliser were compared. The percentage of patients requiring hospital admission for exacerbations of lung disease fell from 56% to 46% (p < 0.01) but the number and duration of admissions was unchanged. Those whose admission duration increased had more severely impaired spirometry when the nebuliser was supplied and had lower activity scores and higher breathlessness scores at the time of interview indicating more severe disease. Approximately half of the compressors were malfunctioning and patients' understanding of the principles of nebuliser treatment was poor. The provision of domiciliary nebuliser can influence hospital admission in patients with obstructive airways disease. There is also a need for improved patient education and for technical support which may require the development of a nurse-run nebuliser service.

Risk factors for adult onset wheeze: a case control study

Risk factors associated with adult onset wheeze were examined in a case control study of subjects aged 39-45 yr derived from a community cohort of 2,056 asymptomatic children originally studied in 1964. Participants included 102 cases with adult onset wheeze (since age 15) and 217 controls with no wheeze. Logistic regression analysis was used to determine independent risk factors for wheeze among all cases and three subgroups: doctor diagnosed asthma (n = 24), wheeze with chronic cough and phlegm (n = 31), and other wheeze (n = 47). The risk of adult onset wheeze among all cases increased with low socioeconomic status (relative risk [RR] 2.36), current smoking (RR 2.01), positive atopic status (RR 3.28), and positive family history of atopic disease (RR 5.49). Gender was not related to the risk of wheezing. The pattern of significant independent risk factors differed between the subgroups of cases. Socioeconomic status was associated with cough and phlegm and other wheeze. Smoking habit was only related to cough and phlegm. Atopy was associated with doctor diagnosed asthma and cough and phlegm. Family history of atopic disease was related to all subgroups, suggesting that despite apparent heterogeneity in diagnostic labeling, concurrent symptoms, and other risk factors, the different forms of adult onset wheeze may share a common allergic basis.

Outcome of children of parents with atopic asthma and transient childhood wheezy bronchitis

BACKGROUND

Childhood asthma and wheeze only in the presence of respiratory infection (wheezy bronchitis) appear to have different prognoses and may differ in their aetiology and heritability. In particular, slight reductions in lung function may be associated with episodes of wheezing associated with intercurrent viral infection.

METHODS

Outcomes for wheezing symptoms and lung function were studied in 133 offspring of three distinct groups of 69 middle aged probands with childhood histories of (1) atopic asthma (n = 18), (2) wheeze associated with upper respiratory tract infection (wheezy bronchitis, n = 24), and (3) no symptoms (n = 27). Probands were selected from a previously studied cohort in which outcomes of wheezy bronchitis and asthma had been shown to differ.

RESULTS

Children of probands with wheezy bronchitis had a lower prevalence of current wheezing symptoms. Forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) in boys of probands with a history of wheezy bronchitis were significantly reduced compared with either of the other two groups (p < 0.0001). In a multivariate analysis, grouping based on parent proband had a significant effect on lung function, independent of factors such as symptoms, atopy or smoking history.

CONCLUSIONS

The different symptomatic and lung function outcome in children of probands with wheezy bronchitis and asthma provides further evidence that wheezy bronchitis and asthma differ in their natural history and heritability, and suggests that there may be familial factors specific to each wheezing syndrome.

Quality of life and hospital re-admission in patients with chronic obstructive pulmonary disease

BACKGROUND

There is some evidence that quality of life (QOL) in patients with chronic obstructive pulmonary disease (COPD) may predict clinical outcomes and use of resources. This study examined whether QOL scores could prospectively predict re-admission for COPD or death within 12 months of an original admission, and whether QOL scores predicted home nebuliser provision.

METHODS

The study was carried out in all acute medical wards of Aberdeen Royal Infirmary, Woodend and City Hospitals, Aberdeen over 12 months. A total of 377 patients admitted with an exacerbation of COPD were identified in this time, 111 of whom were not included in the study because they refused the interview or died before discharge. The remaining 266 patients completed the St George's Respiratory Questionnaire (SGRQ). Information on spirometric parameters, nebuliser provision at discharge, provision of domiciliary oxygen, and re-admission within 12 months was collected from patient notes.

RESULTS

The mean age of the patients was 68 years and 53% were men. The mean (SD) forced expiratory volume in one second (FEV1) was 38.8 (18.0)% predicted and forced vital capacity (FVC) was 58.9 (23.8)% predicted. Higher (worse) scores on the SGRQ were significantly related to re-admission for COPD in the next 12 months (difference = 4.8, 95% CI 1.6 to 8.0). Patients who were re-admitted and died from COPD did not differ in SGRQ scores from those who were re-admitted and survived for more than 12 months. Re-admission was not related to sex, age, or pulmonary function. One hundred and thirty eight patients did not have a home nebuliser before admission. Of these, 14 were provided with a home nebuliser at discharge. Patients provided with nebulisers had significantly worse SGRQ scores and worse FVC. The 41 patients given domiciliary oxygen did not differ in SGRQ or spirometric parameters. Logistic regression analysis of the three SGRQ subscales (Symptom, Impact and Activity), adjusting for lung function, age and sex, showed that all three subscales were significantly related to hospital readmission and that Impact scores were related to nebuliser provision. Women did not differ from men in Symptom scores on the SGRQ but differed markedly on the Activity and Impact scales.

CONCLUSIONS

It is concluded that poor scores on the SGRQ, a QOL scale which measures patient distress and coping, are associated with re-admission for COPD and use of resources such as nebulisers, independent of physiological measures of disease severity.

Integrated care for asthma: matching care to the patient

The purpose of the present study was to investigate whether criteria associated with assignment of asthma patients between general practice (GP) care alone, integrated care (shared between GP care and hospital clinic) or conventional specialist review could be identified, and whether outcomes for these patients differed over the next 12 months. Seven hundred and sixty four patients with a diagnosis of asthma and previously assigned to either integrated care or clinic care were reviewed after 1 year and reassigned. These patients were then followed for another 12 months and clinical data were collected over this time. After 12 months in clinic care or integrated care, assignment to integrated care was predicted by previous participation in integrated care (OR 2.94), patient preference for integrated care (OR 3.7), no admission (OR 1.56), fewer steroid courses during the previous year (OR 0.88) and nonattendance at review (OR 0.43) in the previous 12 months. Patient discharge to GP care was predicted by higher level of forced expiratory volume in one second (FEV1) (OR 1.49), lower number of GP consultations for troublesome asthma (OR 0.78), and nonattendance for review in the preceding year (OR 2.15). In the following 12 months, the three groups of patients differed significantly in hospital admissions (Discharged = 0.008; Integrated = 0.12; Clinic = 0.31), bronchodilators prescribed (Discharged = 8.5; Integrated = 10.2; Clinic = 13.9), GP consultations (Discharged = 1.3; Integrated = 3.0; Clinic = 4.1) and oral steroid courses (Discharged = 0.62; Integrated = 1.7; Clinic = 2.4). Patients assigned to integrated care, clinic care or discharged to general practice care form three distinct patient populations differing retrospectively and prospectively in morbidity and admission risk. In particular, patients assigned to integrated care fall midway in risk and morbidity between those discharged or those retained in clinic care. These results suggest that integrated care provides general practitioners with a system of management for asthma patients, for whom they do not wish frequent specialist review but who they do not believe can safely be discharged to general practice care only.

Evaluation of Grampian Smokebusters: a smoking prevention initiative aimed at young teenagers

BACKGROUND

The Health of the nation aims 'to reduce the number of young people who start to smoke'. Smokebusters is a specific health promotion approach with the aim of encouraging non-smoking as the norm and developing a non-smoking peer group.

METHODS

This study of the Grampian club was undertaken to measure any change in the prevalence of smoking as well as knowledge and awareness of the regional Smokebusters club in the target group (10-13-year-olds). School-based questionnaires were administered to a one in ten sample of the target population, followed up four years after the launch of the club, to establish the prevalence of self-reported smoking in comparison with Scottish national smoking surveys, attitudes to smoking and the Smokebusters club, and to explore lifestyle factors.

RESULTS

The club was very popular and attracted over half of the eligible children. After four years, smoking prevalence in Grampian was similar to Scottish levels, and former club members were just as likely to have started smoking as those who had never joined.

CONCLUSIONS

Membership of Smokebusters does not seem to reduce the smoking prevalence among young people. However, Smokebusters competes in a social environment where many adults and children smoke, where it is still fairly easy for children to obtain cigarettes and where tobacco is extensively promoted. This evaluation focused on the outcome of the Smokebusters, and not on the process and impact. Finally, results of this intervention might include long-term benefits for children and the wider community which are not measured by this study.

Outcome of wheeze in childhood: the influence of atopy

We have previously demonstrated that the adult outcome of childhood asthma differs from that of wheeze occurring only in the presence of infection. This paper examines the role of atopy in relation to outcome. We investigated the atopic status, current symptoms and bronchial reactivity to methacholine of 235 subjects aged 34-40 yrs, originally classified at age 10-15 yrs as having asthma (asthma group), wheeze only in the presence of infection (wheezy group), or no respiratory symptoms (comparison group). Subjects from the original asthma group were more likely to be atopic as defined by skin test reactivity, total serum immunoglobulin E (IgE) measurement or specific IgE radio allergosorbent test (RAST) measurement than those from the wheezy group. The wheezy group differed significantly from the reference group only in RAST results, when other variables were taken into account. In a logistic regression model, the important independent predictors for adult wheezing symptoms were original group, atopy and current smoking. Methacholine responsiveness was independently associated with original group (the asthma group were more likely to respond positively), atopy and female gender. The results suggest that atopy is an important predictor for wheeze and bronchial hyperreactivity in middle age. However, the difference in outcome for children who had asthma compared to those who had wheeze only in the presence of infection cannot be explained by atopy alone.

Penetration of amoxycillin/clavulanic acid into bronchial mucosa with different dosing regimens

BACKGROUND

The efficacy of an antibiotic is related to its concentration at the site of infection. Previous studies of the concentrations of amoxycillin and clavulanic acid (co-amoxiclav) in respiratory secretions or whole lung tissue have suffered from methodological problems. The concentration of amoxycillin and clavulanic acid was determined in bronchial mucosal biopsy samples obtained at bronchoscopy following five different dosing regimens.

METHODS

Bronchial biopsy and serum samples were obtained from 50 patients undergoing diagnostic bronchoscopy. Ten patients each received 375 mg, 625 mg, 750 mg, and 3.25 g oral, and 1.2 g intravenous co-amoxiclav 1-3 hours before bronchoscopy. The concentrations of clavulanic acid and amoxycillin were determined by high performance liquid chromatography using a microbore column, solid phase extraction, and preconcentration to improve sensitivity tenfold over previous methods.

RESULTS

Concentrations of both clavulanic acid and amoxycillin in bronchial mucosa were dose related and were well above the MIC90 of co-amoxiclav for the common bacterial respiratory pathogens including Haemophilus influenzae, Micrococcus catarrhalis and Streptococcus pneumoniae for all dosing regimens. Mean mucosal levels were 200% and 118% of the corresponding serum levels for amoxycillin and clavulanic acid respectively.

CONCLUSIONS

Amoxycillin and clavulanic acid are concentrated in bronchial mucosa and, even at the lowest dose of 375 mg orally, are likely to produce tissue levels in the lung sufficient to inhibit all the common community acquired respiratory pathogens.

Reducing hospital admission through computer supported education for asthma patients. Grampian Asthma Study of Integrated Care (GRASSIC)

OBJECTIVE

To evaluate a personalised computer supported education programme for asthma patients.

DESIGN

Pragmatic randomised trial comparing outcomes over 12 months between patients taking part in an enhanced education programme (four personalised booklets, sent by post) and patients receiving conventional oral education at outpatient or surgery visits.

SETTING

Hospital outpatient clinics and general practices in north east Scotland.

SUBJECTS

801 adults attending hospital outpatient clinics, with a diagnosis of asthma confirmed by a chest physician and pulmonary function reversibility of at least 20%.

MAIN OUTCOME MEASURES

Numbers of hospital admissions, consultations with general practitioner for asthma, steroid courses used, bronchodilators and inhaled steroids prescribed, days of restricted activity, and disturbed nights.

RESULTS

Patients with asthma judged too severe for randomisation between clinic care and integrated care and thus retained in clinic care had 54% fewer hospital admissions after receiving enhanced education than did the control group (95% confidence interval 30% to 97%; P < 0.05) over the study year. Patients had not all spent a full year as "educated" patients within the study year: when "educated days" were controlled for, annual admission rates for the entire enhanced education group were 49% (31% to 78%) of those in the control group. Among patients with sleep variation, sleep disturbance in the education group in the week before a regular review was 80% (65% to 97%) of that in the control group. There was no significant difference in days of restricted activity, prescription of bronchodilators or inhaled steroids, use of oral steroids, or number of general practitioner consultations for asthma, and no significant interaction between ownership of a peak flow meter and education.

CONCLUSIONS

An asthma education programme based on computerised booklets can reduce hospital admissions and improve morbidity among hospital outpatients.

Outcome of wheeze in childhood. Symptoms and pulmonary function 25 years later

The outcome after 25 yr was studied for three groups of children classified in a random community survey in 1964 as having asthma (121 subjects), wheeze in the presence of infection (167 subjects), or no respiratory symptoms (167 comparison subjects). Approximately 80% of the subjects in each group, now aged 34 to 40 yr, were successfully traced. Current symptoms and smoking habit were recorded by questionnaire, and ventilatory function, peak flow variability, and bronchial reactivity to inhaled methacholine were measured. Subjects who had asthma in childhood were more likely to wheeze (odds ratio [OR] 14.4) or produce phlegm (OR 3.3) than comparison subjects. They also had significantly lower FEV1 values and greater bronchial reactivity than comparison subjects. Adult FEV1 correlated with childhood FEV1 (both expressed as % of predicted) (r = 0.44, p < 0.01). The prognosis for those children who were classed as having wheeze in the presence of infection in 1964 was better than for those who had asthma. Although they also were more likely to report wheeze (OR 3.8) or phlegm (OR 4.4) than comparison subjects, the wheezy symptoms were unlikely to interfere with activities and the ventilatory function and bronchial reactivity to methacholine did not differ from those of comparison subjects. Smokers were more likely to report wheeze (OR 2.0), cough (OR 7.2), and phlegm (OR 3.1) than never-smokers, and current smokers with current wheezy symptoms had significantly reduced FEV1 values, although smoking was not associated with increased methacholine reactivity.(ABSTRACT TRUNCATED AT 250 WORDS)

Six months versus nine months chemotherapy for tuberculosis of lymph nodes: final results

Of 199 patients treated for peripheral lymph node tuberculosis, 157 completed treatment as planned. Fifty received E2H9R9, 56 Z2 H9R9 and 51 Z2H6R6 regimens (E = Ethambutol; H = Isoniazid; R = Rifampicin; Z = pyrazinamide: numbers denote duration of therapy in months). In follow-up from 9 to 30 months, there were no significant differences between the regimens in enlargement of existing nodes, development of new glands or sinuses, in the need for new operative procedures, or in the percentage with measurable nodes at 30 months. Nine patients were felt to have had a clinical relapse (4 E2H9R9; 2 Z2H9R9; 3 Z2H6R6) although this was not confirmed bacteriologically in the five cases where material was sent for culture. These differences were not statistically different. The 6 month Z2H6R6 regimen performs just as well as the 9 month regimens Z2H9R9 and E2H9R9 in patients with fully sensitive organisms, and has the additional benefits of convenience and reduced cost.

Spontaneous sternal fractures in four patients with chronic airflow obstruction taking corticosteroids

Four patients with chronic airflow obstruction developed spontaneous sternal fractures. All had received repeated courses of high dose corticosteroids and three were receiving long term treatment with low dose corticosteroids. It is important to consider sternal fracture in the differential diagnosis when patients with chronic airflow obstruction present with chest pain.

Predicting patient attitudes to asthma medication

BACKGROUND

Studies of patient attitudes to asthma and its control have focused on crisis action, and little attention has been paid to attitudes to regular preventive medication. It is not clear whether attitudes to regular medication are related to the degree of distress or interference with life perceived by patients as being caused by their asthma. For this reason this study examined how far dislike of medication related to dislike of other aspects of interference of asthma with daily life.

METHODS

Three hundred and ninety one patients were surveyed with a questionnaire which assessed their dislike of the interference of asthma with their physical, social, and emotional functioning, together with dislike of regular asthma medication. A response was received from 320 patients (82%).

RESULTS

Four attitude clusters were identified. Recorded in descending factor order, these were (1) dislike of asthma medication, (2) dislike of disability, (3) dislike of public life interference, and (4) dislike of social and emotional interference. The attitude clusters were not related: in particular, dislike of asthma medication could not be predicted from other dislikes, or from asthma best function ratio (ratio of best recorded peak expiratory flow rate in the previous year to predicted value), age, or sex. The most significant predictors of the patients' dislike of taking their own inhaled steroid were (1) dislike of using bronchodilator, (2) dislike of steroids generally, and (3) dislike of taking medicine every day.

CONCLUSIONS

Patient attitudes to regular asthma medication are not related to general anxieties and dislikes about asthma, nor to the potential for asthma control as judged by the best function ratio. Patients were not always consistent in their attitude to inhaled steroids in general, nor to their own named inhaled steroid in particular. A general cluster of antimedication attitudes existed, independent of whether the medication was for prophylaxis or relief. Attitudes to asthma medication may be helpful in predicting patient behaviour.

Identifying asthmatic patients in the community: a new method

Identifying a random sample of patients in the community has long proved problematic. In 1989 changes were made in the management of adult asthmatic patients referred to specialist clinics in the Grampian Health Board area. In order to estimate the effect of these changes on the management of patients not referred, it was necessary to identify two random samples of adult asthmatic patients treated solely in general practice. As it was felt that existing methods were open to bias and other errors, a method using National Health Service drug prescription forms was devised. Following the computerization of the Pharmacy Practice Division in Aberdeen, a similar method for the identification of a follow-up sample had to be devised. Nearly 400 general practitioners (86% of those eligible) took part in the first sampling in 1989; 96% of those contacted participated in the second sampling in 1991. Both methods were effective in identifying asthmatic patients in the community. Computerization has made the task simpler, less time consuming and, as a consequence, most cost effective.

Prevalence of cystic fibrosis mutations in the Grampian region of Scotland

We have identified all known sufferers of cystic fibrosis (CF) alive in the Grampian region, north east Scotland, on 1 January 1989. DNA samples were obtained for a prevalence study of the common mutations with near to complete ascertainment. A relatively high prevalence of the delta F508 mutation was found (82%), with one of four mutations being present on 92% of CF chromosomes. The high prevalence of these four easily detectable mutations in Grampian has local implications for genetic counselling, the efficacy of population carrier screening, and the usefulness of mutation analysis in cases where the diagnosis of CF is in doubt.

Smoking habits of Grampian school children and an evaluation of the Grampian Smoke Busters campaign

To determine the effect of a Smoke Busters club in reducing the numbers of children recruited to smoking, levels of smoking in Grampian amongst 11-14 year olds were determined at the launch of the club and again 22 months later, using a self-completion questionnaire. Initial smoking levels were similar to Scottish Office of Population Censuses and Surveys (OPCS) 1986 figures taken 2 years prior to the first Grampian survey. OPCS findings indicated that in Scotland smoking levels had remained fairly stable among girls and had increased among boys between 1986 and 1990. At the second survey in Grampian, smoking levels among girls and boys were lower than in Scotland generally, but it is not possible to know whether this was a result of the campaign or not. There was evidence of a relationship between the smoking habits of children and parents, particularly their mothers. Life-style questions showed that smokers were more likely to take part in activities characteristic of older teenagers and to prefer music which was associated with alternative, rebellious attitudes. Smoke Busters clubs aim to promote a non-smoking life-style amongst young teenagers. After 22 months of a Smoke Busters club, it was evident that at least 32.9% of the target group had joined the club at some point and that it was very popular with its members. Those who joined Smoke Busters were more than twice as likely to remain non-smokers as those who were non-members, but this might not be a function of cause and effect. A further survey is to be undertaken at 4 years after the launch of the club and may allow assessment of any longer-term effects of the club in Grampian.

Achilles tendon rupture: an underrated complication of corticosteroid treatment

Ten patients attending outpatient clinics who were taking oral corticosteroids ruptured their Achilles tendon in the course of 12 years. It is suggested that Achilles tendon rupture is a complication of corticosteroid treatment.

Paraquat induced pulmonary fibrosis in three survivors

Pulmonary lesions following paraquat poisoning are believed to be almost invariably fatal. The three patients reports here survived despite persistent radiological change. One of the patients died after taking a larger dose of paraquat one year later, and at necropsy histological changes attributable to the two episodes of paraquat poisoning were apparent.

Air-driven nebulised high-dose salbutamol in severe chronic obstructive airways disease: is it safe?

The increasing use of air-driven nebulised bronchodilators by patients with airflow obstruction has raised concern about the safety of this practice. We have investigated the effects of 10 mg salbutamol, nebulised in air, on blood gas tensions, heart rate and plasma potassium (K+), when administered alone to 9 patients with severe chronic obstructive airway disease and then in combination with a therapeutic dose of oral sustained-release theophylline to 5 of them on 2 separate occasions. No significant reductions in PaO2 were observed with either treatments. Heart rate increased significantly from 77.8 +/- 3.7 beats/min (mean +/- s.e.m.) at baseline to a peak of 87.1 +/- 4.4 beats/min at 45 min (p less than 0.001) with salbutamol alone and there was a similar trend of increase after combined therapy. K+ decreased significantly from a baseline of 4.0 +/- 0.3 to a minimum of 3.6 +/- 0.2 mmol/l at 90 min (p less than 0.001) with combined therapy but did not change significantly with single therapy. No subject developed any significant cardiac arrhythmias on either occasion. Although the number of subjects studied is small, our data suggest that air-driven nebulised high-dose salbutamol may be safe in the treatment of severe chronic obstructive airway disease but when combined with oral theophylline, a significant fall in plasma potassium may occur. This could be of clinical significance in hypokalaemic patients. When combination treatment is used, monitoring of plasma potassium is recommended.

Use of nebulised saline and nebulised terbutaline as an adjunct to chest physiotherapy

To determine whether sputum clearance is increased by using nebulised saline or terbutaline as an adjunct to chest physiotherapy, a radioaerosol method (using technetium-99m labelled human albumin millimicrospheres) was employed in eight patients with stable bronchiectasis on four occasions, for comparison of sputum clearance with four different regimens. These were: control, with the patient resting in an upright position; chest physiotherapy, by the forced expiration technique with postural drainage; and chest physiotherapy following five minutes' inhalation of either nebulised normal saline or nebulised terbutaline 5 mg. Use of both nebulised saline and nebulised terbutaline immediately before chest physiotherapy gave a significantly greater yield of sputum than did physiotherapy alone, and terbutaline also significantly increased radioaerosol clearance from the whole lung and from regions of interest. The mechanism is unclear, but this method may provide a simple way of increasing the efficacy of conventional chest physiotherapy.

How well do asthma clinic patients understand their asthma?

Fifty asthmatic patients attending a hospital asthma clinic were interviewed to determine their understanding of their asthma and its treatment. Serious defects were found in their ability to judge the severity of their asthma, in their knowledge of medication, and in the correct action to take when deterioration in control occurred. Several risk factors previously identified in studies of asthma deaths were also present in this living population--in particular, delay in seeking medical help until critically ill, and lack of awareness of danger signs. There was evidence of poor patient-doctor contact and unsuccessful patient education.

Acute renal failure due to continuous rifampicin

We describe the clinical and pathological features of acute renal failure which occurred in a patient receiving a first course of antituberculous therapy, including daily rifampicin. Renal biopsy specimens demonstrated an interstitial nephritis. The renal lesion resolved three weeks after the cessation of rifampicin, as evidenced by improvement in renal function and the return of nuclear magnetic resonance tomographic studies to normal. This is only the fifth reported instance of renal impairment following continuous rifampicin therapy, despite widespread use of the drug in a daily dose. The possible toxic interaction of rifampicin and antituberculous drugs which are excreted predominantly by the kidneys is also described.

New Terrestrial Amphipods (Amphipoda:Talitridae) From Australian Forests

Descriptions of two new genera including five new species of Australian landhoppers are presented. Two new species are recorded from south-west Western Australia (Austrotroides pectinalis and A. occidentalis) and one each from the Adelaide area (A. crenatus), southern Victoria (Agilestia hyperocha) and southern Queensland-northern New South Wales (A. hylaea). Notes on the life history of Austrotoides crenatus are provided.

Progressive lung disease in a malt-worker

We described a malt-worker whose initial symptoms suggested extrinsic allergic alveolitis. The ensuing cavitating lung disease, Aspergillus fumigatus infection with mycetomata, vigorous immune response, and granulomatous liver disease are unusual features.

Pulmonary hypersensitivity in prawn workers

In a prawn-processing factory, workers were exposed to an aerosol of prawn. Nearly 40% of those exposed developed wheezing and other respiratory symptoms.

Sarcoid pleural effusion: three cases and review of the literature

Pleural sarcoidosis is rare--it is little recognised in Birtian although several cases have been reported in the international literature. Three white men with pleural effusions caused by sacroidosis have been seen in a two-year period when approximately 60 new cases of thoracic sarcoidosis have been presented. In one patient a recurrent massive effusion was only diagnosed as being caused by sarcoidosis after thoractomy, and in two further patients small symptomatic pleural effusions were present at the onset of typical sarcoidosis. Two patients were successfully treated with steroids and the third improved spontaneously. Percutaneous biopsy is not always helpful in diagnosing pleural sarcoidosis, but a lymphocytic, often blood-stained, pleural aspirate is highly characteristic. While other diseases may coexist, a pleural effusion in a patient with histologically proven sarcoidosis is more likely to be caused by the primary disease than by any other condition.

Blood flow in pulmonary veins: I. Studies in dog and man

The pattern of blood flow in the large extra parenchymal pulmonary veins is pulsatile in both dog and man. This pulsatility is dominated by the changes in left atrial pressure taking place throughout the cardiac cycle. No pulsatile component of low in the large pulmonary veins could be attributed to forward transmission of a flow pulse conducted from the lung capillaries. The findings suggest that there must be a region of considerable compliance in the pulmonary venous system which can absorb pulsations from the lung capillaries and eliminate their transmission to the left atrium.

Blood flow in pulmonary veins: II. The influence of events transmitted from the right and left sides of the heart

The wave form of blood flow in the large extra parenchymal pulmonary veins has an inverse relationship to the pressure wave form in the left atrium during each cardiac cycle. However, when vein flow from the lungs is separated from the left atrium by diverting it into a constant pressure reservoir, its wave form then resembles a lung capillary flow pulse, though delayed from it in time and reduced in ampliture. The pulsatility of flow in pulmonary veins separated from the left atrium is further reduced when transcapillary pressure is elevated by lung inflation. However, in the intact state, the relation between the pattern of pulmonary vein flow and left atrial pressure remains unaffected by lung inflation. It is postulated that the thin walled extraperenchymal pulmonary veins together behave as a collapsible reservoir which enables outflow from them to be determined by changes in left atrial pressure, in spite of variations of pulsatile flow into them from the lungs.