The effect of intra-operative hypotension on acute kidney injury, postoperative mortality and length of stay following emergency hip fracture surgery.

The association between intra-operative hypotension and postoperative acute kidney injury, mortality and length of stay has not been comprehensively evaluated in a large single-centre hip fracture population. We analysed electronic anaesthesia records of 1063 patients undergoing unilateral hip fracture surgery, collected from 2015 to 2018. Acute kidney injury, 3-, 30- and 365-day mortality and length of stay were evaluated to assess the relationship between intra-operative hypotension absolute values (≤ 55, 60, 65, 70 and 75 mmHg) and duration of hypotension. The rate of acute kidney injury was 23.7%, mortality at 3-, 30- and 365 days was 3.7%, 8.0% and 25.3%, respectively, and median (IQR [range]) length of stay 8 (6-12 [0-99]) days. Median (IQR [range]) time ≤ MAP 55, 60, 65, 70 and 75 mmHg was 0 (0-0.5[0-72.1]); 0 (0-4.4 [0-104.9]); 2.2 (0-8.7 [0-144.2]); 6.6 (2.2-19.7 [0-198.8]); 17.5 (6.6-37.1 [0-216.3]) minutes, and percentage of surgery time below these thresholds was 1%, 2.5%, 7.9%, 12% and 21% respectively. There were some univariate associations between hypotension and mortality; however, these were no longer evident in multivariable analysis. Multivariable analysis found no association between hypotension and acute kidney injury. Acute kidney injury was associated with male sex, antihypertensive medications and cardiac/renal comorbidities. Three-day mortality was associated with delay to surgery ? 48 hours, whilst 30-day and 365-day mortality was associated with delay to surgery ≥ 48 hours, impaired cognition and cardiac/renal comorbidities. While the rate of acute kidney injury was similar to other studies, use of vasopressors and fluids to reduce the time spent at hypotensive levels failed to reduce this complication. Intra-operative hypotension at the levels observed in this cohort may not be an important determinant of acute kidney injury, postoperative mortality and length of stay.

Congruence between arthropod and plant diversity in a biodiversity hotspot largely driven by underlying abiotic factors.

Plants often form the basis of conservation planning and management. The effectiveness of plant diversity as a surrogate for arthropod diversity was assessed in natural areas in the Kogelberg Biosphere Reserve, a floral endemism hotspot in the Cape Floristic Region (CFR), South Africa. Arthropods and plants were sampled across 30 topographically heterogeneous sites in a spatially nested design. The relationship between plants and arthropods were quantified in terms of species richness, assemblage variation, and assemblage turnover. The influence of arthropod trophic groups, habitat association, and spatial scale were also explored. Generalized dissimilarity modelling was used to investigate differential influence of explanatory groups (geology, disturbance, local site characteristics, refuge, mesoclimate, terrain) on arthropod and plant turnover. Congruence in assemblage variation was restricted to local scales, and only present between plants and those arthropods associated with the foliar component of the habitat. Weak congruence in species turnover was due to differences in the relative importance of explanatory groups, with different variables within each explanatory group being important, and similar variables predicting different turnover patterns. For both groups, variables related to geology and fire history were important for assemblage turnover. These variables are already incorporated in conservation planning and management for plant diversity across the CFR. Overall plant diversity was a weak surrogate for the arthropod groups included in this study, suggesting that as an alternative, environmental surrogates for arthropod diversity perform better.

A case series of third-trimester raltegravir initiation: Impact on maternal HIV-1 viral load and obstetrical outcomes.

OBJECTIVE: To describe the impact of initiating raltegravir (RAL)-containing combination antiretroviral therapy (cART) regimens on HIV viral load (VL) in pregnant women who have high or suboptimal VL suppression late in pregnancy. METHODS: HIV-infected pregnant women who started RAL-containing cART after 28 weeks' gestation from 2007 to 2013 were identified in two university hospital centres. RESULTS AND DISCUSSION: Eleven HIV-infected women started RAL at a median gestational age of 35.7 weeks (range 31.1 to 38.0 weeks). Indications for RAL initiation were late presentation in pregnancy (n=4) and suboptimal VL suppression secondary to poor adherence or viral resistance (n=7). Mean VL at the time of RAL initiation was 73,959 copies/mL (range <40 to 523,975 copies/mL). Patients received RAL for a median of 20 days (range one to 71 days). The mean decline in VL from the time of RAL initiation to delivery was 1.93 log, excluding one patient who received only one RAL dose and one patient with undetectable VL at the time of RAL initiation. After eight days on RAL, 50% of the women achieved a VL <1000 copies/mL (the threshold for recommended Caesarean section to reduce the risk for perinatal transmission). There were no cases of perinatal HIV transmission. CONCLUSION: The present study provides preliminary data to support the use of RAL-containing cART to expedite HIV-1 VL reduction in women who have a high VL or suboptimal VL suppression late in pregnancy, and to decrease the risk of HIV perinatal transmission while avoiding Caesarean section. Further assessment of RAL safety during pregnancy is warranted.

OBJECTIF: Décrire les répercussions de l'amorce d'une antirétrovirothérapie prophylactique associative (ARPA) contenant du raltégravir (RAL) sur la charge virale (CV) du VIH chez les femmes enceintes dont la suppression de la CV est élevée ou sous-optimale en fin de grossesse. MÉTHODOLOGIE: Les chercheurs ont extrait le dossier des femmes enceintes infectées par le VIH qui avaient amorcé une ARAP contenant du RAL après 28 semaines de grossesse dans deux centres hospitaliers universitaires entre 2007 et 2013. RÉSULTATS ET EXPOSÉ: Onze femmes infectées ont entrepris un traitement de RAL à une médiane de 35,7 semaines de grossesse (plage de 31,1 à 38,0 semaines). Les indications pour entreprendre le RAL étaient une présentation tardive au suivi de grossesse (n=4) et une suppression sous-optimale de la CV en raison d'un mauvais respect du traitement ou d'une résistance virale (n=7). La CV moyenne au début du traitement au RAL était de 73 959 copies/mL (plage de moins de 40 copies/mL à 523 975 copies/mL). Les patientes ont pris du RAL pendant une médiane de 20 jours (plage de un à 71 jours). La diminution moyenne de la CV entre le début du RAL et l'accouchement était de 1,93 log, à l'exception d'une patiente qui n'a reçu qu'une dose de RAL et d'une patiente dont la CV n'était pas décelable au moment d'entreprendre le RAL. Au bout de huit jours de RAL, 50 % des femmes présentaient une CV inférieure à 1 000 copies/mL (le seuil pour recommander une césarienne afin de réduire le risque de transmission périnatale). Il n'y a d'ailleurs eu aucun cas de transmission périnatale du VIH. CONCLUSION: La présente étude fournit des données provisoires pour soutenir l'utilisation d'ARPA contenant du RAL afin d'accélérer la réduction de la CV du VIH-1 chez les femmes qui présentaient une CV élevée ou une suppression sous-optimale de leur CV pendant la grossesse, ainsi que pour réduire le risque de transmission périnatale du VIH tout en évitant une césarienne. Une évaluation plus approfondie de l'innocuité du RAL est justifiée pendant la grossesse.

CT scan the key to unmasking a solid pseudopapillary pancreatic neoplasm in blunt abdominal trauma.

SUMMARY: We present a previously healthy 13-year-old male, who sustained a handlebar injury after falling from his bicycle. The computerised tomography (CT) scan indicated a probable pancreatic neoplasm associated with a retroperitoneal haematoma which was, following resection, confirmed histologically to be a solid pseudopapillary neoplasm of the pancreas. These are rare tumours of the pancreas, especially in young males. The rarity of this neoplasm and the mechanism that led to its presentation make this an interesting and unique case.

Does manual anaesthetic record capture remove clinically important data?

BACKGROUND: Numerous studies have shown smoothing and inaccuracies in handwritten anaesthetic records, but the clinical relevance of these findings is unclear. We therefore sought to determine whether the behaviour of anaesthetists differed in assessing anaesthetic records re-synthesized from either handwritten or automated records. METHODS: In a recent New Zealand study (ACTRN12608000068369), both manual and automated records were acquired from the same anaesthetics. Manual records were digitized using digital callipers. Selected data (systolic, diastolic, and mean arterial pressure; heart rate; Sp(O(2)); E'(CO(2))) were replayed in a computerized anaesthetic record-keeping system with which the participants were familiar, to present manual and corresponding automated anaesthetic records. Ten anaesthetists, randomly selected from participants in this study, assessed 24 replayed records (a manual and an automated record from each of 10 anaesthetics, with two of each displayed twice). They indicated where and how they would have intervened if administering these anaesthetics. We compared the number of interventions for each pair of anaesthetics and subjective measures of anaesthetic quality. RESULTS: In our selected sample of unstable anaesthetics, the mean (SD) number of interventions per anaesthetic was 4.0 (2.9) vs 5.2 (3.4) for manual and automated records, respectively (P=0.013). Subjective measures did not differ significantly between record types. Assessors identified 32 artifacts in six manual records (0.32/record assessment) and 105 artifacts in eight automated records (1.05/record assessment), P=0.14. Replicability was moderate (COV 39.8%). CONCLUSIONS: In comparison with computerized record-keeping, manual record-keeping resulted in loss of clinically relevant information.

Environmental filtering and spillover explain multi-species edge responses across agricultural boundaries in a biosphere reserve.

To ensure integrity of protected areas we need to understand how species respond to anthropogenic borders. We investigate, from a metacommunity perspective, the direct and indirect mechanisms by which transformed areas affect distribution patterns of ground-living arthropod assemblages inhabiting an extensive protected area adjacent to fruit orchards in an important biosphere reserve. Arthropods and environmental variables were sampled along transects perpendicular to natural-orchard edges. Influence of distance from orchard boundary, degree of impermeability of the boundary, orchard habitat quality (local scale land-use intensity), and edge-induced changes in local environmental variables on arthropod species richness and composition in non-crop habitats were assessed. Arthropod groups were assessed in terms of habitat fidelity: species associated with natural habitat (stenotopic species), those within crop habitat (cultural species), and those showing no preference for either habitat (ubiquitous species). Spillover resulted in higher cultural species richness near edges, but not higher overall species richness. Environmental filtering was important for stenotopic species composition, which was influenced by edge-induced changes in environmental variables. Ubiquitous species composition was determined by orchard impermeability. Increased orchard habitat quality was associated with higher cultural and ubiquitous species richness. The effects of orchards on assemblages in natural habitats can be variable, but predictable when using species habitat specificity in conjunction with a metacommunity framework. High intensity orchards may act as sink habitats, especially for species that readily disperse between crop and natural habitats. Here we recommend that local buffer strips are > 85 m wide, which will reduce the influence of cultural species spillover on sensitive natural ecosystems.

Serious toxicity associated with continuous nevirapine-based HAART in pregnancy.

OBJECTIVE: This study was designed to determine the safety of nevirapine (NVP)-based highly active antiretroviral therapy (HAART) in a cohort of HIV-positive pregnant women. DESIGN: This was a prospective cohort study of HIV-positive pregnant women. POPULATION AND SETTING: All HIV-positive women treated with HAART during pregnancy from January 1997 to February 2004 at the British Columbia (BC) Women's Hospital in Vancouver, BC, Canada. METHODS: Demographic and clinical data were collected to compare antiretroviral drug toxicities in women treated antenatally with NVP-based or non-NVP-based HAART. Multivariate analyses were then used to investigate determinants of toxicity. RESULTS: From 1997 to 2004, 103 HIV-positive pregnant women received HAART. Equivalent numbers of women were initially treated with NVP-based (54%) and non-NVP-based (46%) HAART. The groups did not differ by clinical or demographic parameters and duration of HAART exposure was similar between groups. Toxicities necessitating treatment discontinuation were observed in 6 of 56 NVP-exposed women (2 cases each of grade 2, 3, and 4 toxicity) compared with 1 of 47 in the non-NVP-exposed women. First time use of NVP approached significance as a predictor for toxicity, with a toxicity rate of 12.5% (6/48) observed among those taking NVP for the first time (adjusted OR 2.68, 95% CI 0.49-14.6). CONCLUSION: Continuous NVP use in pregnancy resulted in a relatively higher rate of toxicity, and all cases of NVP toxicity occurred in women exposed to NVP for the first time during pregnancy.

Frequency responses of infant air-balloon versus liquid-filled catheters for intra-esophageal pressure measurement.

Amplitude and phase frequency response characteristics of infant air-balloon catheters (IABC) of differing French gauge (FG) sizes and brands were quantified to determine their suitability for measuring dynamic intra-esophageal pressure (Pes) accurately. Frequency response performances of matching IABC and water-filled catheters (WFC) were also compared using the swept sine wave technique. The maximum respiratory rate within which IABCs could potentially measure Pes within a 5% error limit was calculated (FRR). Frequency responses of IABCs greater than FG size 5 exhibited underdamped resonant properties, while smaller FG size IABCs exhibited near-critical damping or overdamping. IABCs maintained uniform amplitude frequency responses up to 25 Hz, demonstrating the ability to measure Pes potentially up to 148 breaths/min within a 5% error limit. The frequency response performance of FG size 6 IABCs was similar to that of FG size 10 IABCs. Compared with matching WFCs, the frequency response performance of IABCs was significantly superior, the frequency response variability within IABC samples was lower, and IABC correlation between FG size and FRR was advantageously lower than for WFCs. FRR values for differing IABC brands and FG sizes are presented. We conclude that IABCs manufactured to infant-appropriate balloon specifications exhibit significantly superior frequency response characteristics compared with matching WFCs. Measurement accuracy is not improved using IABCs greater than FG size 6. Inexpensive intra-esophageal IABCs are technical suitable for the accurate measurement of dynamic Pes during high-frequency respiratory mechanics encountered during infant artificial ventilation.

Effect of biological contamination on dentine bond strength of adhesive resins.

The purpose of this in vitro study was to determine the effect of saliva (S) and blood (B) contamination on the dentine bond strength of two single-component dentine bonding systems. The occlusal thirds of 120 recently extracted, human molars were removed with a low speed saw and subsequently embedded in Bencor rings by means of self-curing, acrylic resin. The occlusal surfaces were ground wet on 600-grit silicone carbide paper in a polishing machine to expose superficial dentine and to create a smear layer. The teeth were randomly divided into 12 groups (n = 10). All the dentine surfaces were etched with 34% phosphoric acid for 15 seconds rinsed with water, air-dried for 3 seconds, leaving the surfaces visibly moist. For the control groups (C) the etched dentine surfaces were treated with either, Scotchbond 1 (SB1, 3M) or Prime & Bond NT (PBNT, Dentsply) according to the manufacturer's instructions. In the contaminated groups, the saliva or blood was applied by means of a disposable brush, left undisturbed for 1 minute, and the excess then thinned by air spray. The dentine bonding systems were then applied, also according to manufacturer's instructions. Composite (Z250 and TPH) and Compomer (F2000 and Dyract AP (D-AP)) stubs were packed and cured incrementally to the corresponding pretreated dentine surfaces. All specimens were stored for 24 hours under water at 37 degrees C. The bonds were then stressed to failure with a Zwick testing machine, operating at a crosshead speed of 0.5 mm/min. Fractured samples were examined in a Scanning Electron Microscope. The data were statistically analysed (Student-t test). The mean SBS (MPa) were. SB1 with Z250: C = 19.1 +/- 4.4; S = 17.3 +/- 3.5; B = 2.6 +/- 0.9; SB1 with F2000: C = 11.8 +/- 3.3; S = 9.7 +/- 1.8; B = 4.7 +/- 1.6. PBNT with TPH: C = 9.2 +/- 3.2; S = 6.5 +/- 3.0; B = 4.3 +/- 1.5; PBNT with D-AP: C = 10.2 +/- 3.6; S = 9.3 +/- 2.9 and B = 7.3 +/- 2.5. There was no statistical significant difference in shear bond strengths between the control and the saliva-contaminated samples for both systems. There was, however, a significant difference in bond strengths between the control and the blood-contaminated samples. Blood contamination negatively influenced bond strength of bonding systems to dentine.

Epidemiology of Clostridium difficile infection in two tertiary-care hospitals in Perth, Western Australia: a cross-sectional study.

The epidemiology of Clostridium difficile infection (CDI) has changed over time and between countries. It is therefore essential to monitor the characteristics of patients at risk of infection and the circulating strains to recognize local and global trends, and improve patient management. From December 2011 to May 2012 we conducted a prospective, observational epidemiological study of patients with laboratory-confirmed CDI at two tertiary teaching hospitals in Perth, Western Australia to determine CDI incidence and risk factors in an Australian setting. The incidence of CDI varied from 5.2 to 8.1 cases/10 000 occupied bed days (OBDs) at one hospital and from 3.9 to 16.3/10 000 OBDs at the second hospital. In total, 80 patients with laboratory-confirmed CDI met eligibility criteria and consented to be in the study. More than half (53.8%) had hospital-onset disease, 28.8% had community-onset and healthcare facility-associated disease and 7.5% were community-associated infections according to the definitions used. Severe CDI was observed in 40.0% of these cases but the 30-day mortality rate for all cases was only 2.5%. Besides a shorter length of stay among cases of community-onset CDI, no characteristics were identified that were significantly associated with community-onset or severe CDI. From 70 isolates, 34 different ribotypes were identified. The predominant ribotypes were 014 (24.3%), 020 (5.7%), 056 (5.7%) and 070 (5.7%). Whereas this study suggests that the characteristics of CDI cases in Australia are not markedly different from those in other developed countries, the increase in CDI rate observed emphasizes the importance of surveillance.

Primate pleuroesophageal tissue barrier frequency response and esophageal pressure waveform bandwidth in health and acute lung injury.

BACKGROUND: Dynamic intraesophageal pressure (Pes) is used to estimate intrapleural pressure (Ppl) to calculate lung compliance and resistance. This study investigated the nonhuman primate Ppl-Pes tissue barrier frequency response and the dynamic response requirements of Pes manometers. METHODS: In healthy monkeys and monkeys with acute lung injury undergoing ventilation, simultaneous Ppl and Pes were measured directly to determine the Ppl-Pes tissue barrier amplitude frequency response, using the swept-sine wave technique. The bandwidths of physiologic Pes waveforms acquired during conventional mechanical ventilation were calculated using digital low-pass signal filtering. RESULTS: The Ppl-Pes tissue barrier is amplitude-uniform within the bandwidth of conventional Pes waveforms in healthy and acute lung injury lungs, and does not significantly attenuate Ppl-Pes signal transmission between 1 and 40 Hz. At Pes frequencies higher than conventional clinical regions of interest the Ppl-Pes barrier resonates significantly, is pressure amplitude dependent at low-pressure offsets, and is significantly altered by acute lung injury. Allowing for 5% or less Pes waveform error, the maximum Pes bandwidths during conventional ventilation were 1.9 Hz and 3.4 Hz for physiologic and extreme-case waveforms in healthy lungs and 4.6 Hz and 8.5 Hz during acute lung injury. CONCLUSIONS: In monkeys, the Ppl-Pes tissue barrier has a frequency response suitable for Ppl estimation during low-frequency mechanical ventilation, and Pes manometers should have a minimum uniform frequency response up to 8.5 Hz. However, the Ppl-Pes tissue barrier adversely affects the accurate estimation of dynamic Ppl at high frequencies, with varied airway pressure amplitudes and offsets, such as the Ppl encountered during high-frequency oscillatory ventilation.

Bradykinesia akinesia inco-ordination test (BRAIN TEST): an objective computerised assessment of upper limb motor function.

OBJECTIVES: A simple and rapid computerised keyboard test, based on the alternating finger tapping test, has been developed to quantify upper limb motor function. The test generates several variables: (1) kinesia score: the number of keystrokes in 60 seconds; (2) akinesia time: cumulative time that keys are depressed; (3) dysmetria score: a weighted index calculated using the number of incorrectly hit keys corrected for speed; (4) incoordination score: a measure of rhythmicity which corresponds to the variance of the time interval between keystrokes. METHODS: The BRAIN TEST(Copyright ) was assessed on 35 patients with idiopathic Parkinson's disease, 12 patients with cerebellar dysfunction, and 27 normal control subjects. RESULTS: The mean kinesia scores of patients with Parkinson's disease or cerebellar dysfunction were significantly slower than normal controls (Parkinson's disease=107 (SD 28) keys/min v cerebellar dysfunction=86+/- (SD 28) v normal controls=182 (SD 26), p<0.001) and correlated with the UPDRS (r =-0.69, p<0.001). The akinesia time is very insensitive and was only abnormal in patients with severe parkinsonism. The median dysmetria (cerebellar dysfunction=13.8 v Parkinson's disease=6.1 v normal controls=4.2, p=0.002) and inco-ordination scores (cerebellar dysfunction=5.12 v Parkinson's disease=0.84 v normal controls=0.15, p=0.002) were significantly higher in patients with cerebellar dysfunction, in whom the dysmetria score correlated with a cerebellar disease rating scale (r=0.64, p=0.02). CONCLUSION: The BRAIN TEST(Copyright ) provides a simple, rapid, and objective assessment of upper limb motor function. It assesses speed, accuracy, and rhythmicity of upper limb movements regardless of their physiological basis. The results of the test correlate well with clinical rating scales in Parkinson's disease and cerebellar dysfunction. The BRAIN test will be useful in clinical studies. It can be downloaded from the Internet ().

A novel study on the effect of acetylsalicylic acid on the binding capacity of estrogen receptors from MCF-7 cells.

The effect of acetylsalicylic acid (ASA, aspirin) was investigated on [3H]-estradiol-17 beta ([3H]-E2) binding to estrogen receptors (ER) from MCF-7 mammary tumour cells. No effect was observed using the monoclonal estrogen receptor-enzyme immunoassay (ER-EIA). In contrast to the ER-EIA, the radioreceptor assay (RRA) showed decreases of [3H]-E2 specific binding in the presence of increasing amounts of ASA. It is therefore concluded that these results demonstrate that ASA possibly affects the direct binding of E2 to region E of the ER of human breast cancer MCF-7 cells, but does not affect binding of monoclonal antibodies to regions D and F of the ER.

Prevalence of asthma: a comparative study of urban and rural Xhosa children.

An epidemiological study was undertaken to determine the prevalence of asthma in young urban and rural black (Xhosa) children. One thousand three hundred and seventy five children were studied, 694 from a Cape Town african township and 671 from a rural area in Transkei. The exercise tolerance test which required free range running at maximum effort for 6 min was used to identify asthmatic subjects. A fall of 15% or more in the post-exercise FEV1 and PEFR values was regarded as a positive result. Twenty-three children were found to be asthmatic, twenty-two from the city area, but only one from the country, giving a prevalence figure for asthma of 3.17% in the first group and 0.14% for the second. Possible reasons for these differences are discussed. The exercise tolerance test was found to be a useful tool for epidemiological studies of asthma.