Attenuated psychosis symptoms are related to working alliance between therapist and service user

AIM

Many trials have demonstrated the efficacy of specific therapy modalities for individuals with attenuated psychosis symptoms (APS). Less is known regarding mechanisms behind positive outcomes, including the role of nonspecific therapeutic factors. This study explored working alliance (WA) in a clinic serving individuals with APS to see how WA changed across the course of treatment and its relation to APS.

METHODS

Session level APS and WA data was available for 12 individuals of diverse racial and gender identity, (M = 48 sessions each). Multilevel models with random intercepts tested change in WA and APS over time, and cross-sectional and prospective relations.

RESULTS

WA increased and APS decreased over time. Cross sectionally, WA and APS were inversely related. Prospective relations were non-significant.

CONCLUSION

When symptoms increase, therapists for individuals with APS should be attentive to potential disruptions in WA, though strong WA may be a cross-sectional protective factor.

Evaluation of delayed timing of artificial insemination with sex-sorted sperm on pregnancy per artificial insemination in seasonal-calving, pasture-based lactating dairy cows

The objective was to use ovulation synchronization with timed artificial insemination (TAI) to evaluate the effect of timing of artificial insemination (AI) with frozen sex-sorted sperm on fertility performance in pasture-based compact calving herds. Ejaculates from 3 Holstein-Friesian bulls were split and processed to provide frozen sex-sorted sperm (SS) at 4 × 10⁶ sperm per straw, and frozen conventional sperm at 15 × 10⁶ sperm per straw (CONV). A modified Progesterone-Ovsynch protocol was used for estrous synchronization, with TAI occurring 16 h after the second GnRH injection for cows assigned to CONV, and either 16 h (SS-16) or 22 h (SS-22) for cows assigned to SS. Pregnancy diagnosis was conducted by transrectal ultrasound scanning of the uterus 35 to 40 d after TAI (n = 2,175 records available for analysis). Generalized linear mixed models were used to examine the effects of treatment on pregnancy per artificial insemination (P/AI). Fixed effects included treatment (n = 3), bull (n = 3), treatment by bull interaction, parity (n = 4), days-in-milk category (n = 3), and treatment by days-in-milk category, with herd (n = 24) included as a random effect. Pregnancy per AI was greater for CONV compared with both SS-16 and SS-22 (61.1%, 49.0%, and 51.3%, respectively), and the SS treatments did not differ from each other (relative P/AI for SS-16 and SS-22 vs. CONV were 80.2% and 84.0%, respectively). There were significant bull and treatment by bull interaction effects. Additional analysis was undertaken using a model that included herd as a fixed effect. This analysis identified marked herd-to-herd variation (within-herd relative P/AI for the combined SS treatments vs. CONV ranged from 48-121%). The tertile of herds with the best performance achieved a mean relative P/AI of 100% (range = 91-121%), indicating that P/AI equivalent to CONV is achievable with SS. Conversely, the tertile of herds with the poorest performance achieved a mean relative P/AI of 67% (range = 48-77%). We found that SS resulted in poorer overall P/AI compared with CONV sperm regardless of timing of AI. Marked variation existed between herds; however, one-third of herds achieved P/AI results equal to CONV. Identification of factors responsible for the large herd-to-herd variation in P/AI with SS, and development of strategies to reduce this variation, warrant further research.

Long term effects of gestational hypertension and pre-eclampsia on kidney function: Record linkage study

•

We examine risk of chronic kidney disease (CKD) after pregnancy hypertension.

•

We found increased risk of chronic kidney disease after gestational hypertension.

•

Risk of chronic kidney disease was further increased after preeclampsia.

•

Women with pregnancy hypertension develop CKD earlier than normotensive women.

Objective

To assess the long term effects of hypertensive disorders of pregnancy on renal function.

Design

Cohort study where exposure was gestational hypertension or preeclampsia in the first pregnancy. Normotensive women formed the comparison group.

Setting

Aberdeen, Scotland.

Participants

All women with date of birth on or before 30th June 1969 and at least their first singleton delivery recorded in the Aberdeen Maternity and Neonatal Databank.

Methods

Participants were linked to the Renal Biochemistry Register, Scottish Morbidity Records, Scottish Renal Registry and National Register for deaths.

Main outcome measures

Occurrence of chronic kidney disease (CKD) as identified from renal function tests in later life, hospital admissions or death from kidney disease or recorded as receiving renal replacement therapy.

Results

CKD was diagnosed in 7.5% and 5.2% of women who previously had GH and PE respectively compared to 3.9% in normotensive women. The unadjusted odds ratio (95% confidence interval) of having CKD in PE was 2.04 (1.53, 2.71) and that for GH was 1.37 (1.15, 1.65), while the adjusted odds ratio (95% confidence interval) of CKD was 1.93 (1.44, 2.57) and 1.36 (1.13, 1.63) in women with PE and GH respectively. Kaplan–Meier curves of survival time to development of chronic kidney disease revealed that women with preeclampsia were susceptible to kidney function impairment earliest, followed by those with gestational hypertension.

Conclusions

There was an increased subsequent risk of CKD associated with hypertensive disorders of pregnancy. Women with GH and PE were also found to have CKD earlier than normotensive women.

Refractory cachexia and truth-telling about terminal prognosis: a qualitative study

The purpose of this paper is to examine the consequences that medical practitioners' decisions about whether or not to be candid about terminal prognosis have for those suffering from refractory cachexia and their families. It presents the findings of a qualitative study that used focus groups and semi-structured interviews of a volunteer sample of doctors, nurses and dieticians in a cancer centre of a large teaching hospital in Northern Ireland. Respondents reported that some physicians tended to avoid discussing terminal prognosis in a direct manner with their patients. Nurses and dieticians tended to be reluctant to engage in conversations about weight loss with patients with cachexia. One of the reasons they reported for their lack of acknowledgement of weight loss concerned the close association between refractory cachexia and terminal prognosis. Because they viewed the telling of bad news as an exclusive prerogative of medical practitioners, they did not feel in a position to discuss cachexia because they were concerned that this had the potential to raise end-of-life issues that lay outside the boundaries of their professional role. This meant patients and their families were provided with little information about how to cope with the distressing consequences of cachexia.

PP038. Are women with gestational hypertension or preeclampsia at an increased long term risk of kidney function impairment?

INTRODUCTION

Preeclampsia is known to cause impairment of kidney function in pregnancy, which manifests as proteinuria. Previous studies have found an association between preeclampsia and kidney disease but were restricted in their numbers or had a short follow up time.

OBJECTIVES

To assess the long term effects of hypertensive disorders of pregnancy on kidney function in later life.

METHODS

From the Aberdeen maternity and neonatal databank (AMND), we identified the first singleton pregnancy of all women with date of birth on or before 30th June 1969. These women were linked by means of their identifying information to the local renal biochemistry database (GRBD). GRBD captures all kidney function tests from primary and secondary care in the health region. A cohort study design was used to assess the odds ratios with 95% confidence intervals for chronic kidney disease stage 1-5 (predefined based on internationally accepted KDOQI definition) occurring at least 1year following delivery. Those with gestational hypertension and preeclampsia were compared to normotensive women using multivariate logistic regression to adjust for potential confounders.

RESULTS

A total of 14675 women who had been linked to the RBD and had complete information regarding age, socio-economic class, smoking category, and body mass index (BMI) were included in a multivariate model. The unadjusted odds ratio (95% confidence interval) of having chronic kidney disease (according to previously stated definition) in preeclamptic women was 2.04 (1.53,2.71) and that in women with gestational hypertension was 1.37 (1.15,1.65), while the adjusted odds ratio (95% confidence interval) of having chronic kidney disease was 1.93 (1.44,2.57) and 1.36 (1.13,1.63) in preeclamptic women and women with gestational hypertension respectively compared to women who were normotensive in their first pregnancy.

CONCLUSION

Women who had gestational hypertension or preeclampsia in their first pregnancy had a higher risk of impairment of renal function compared to women who were normotensive.

UKHCDO guidelines on the management of HCV in patients with hereditary bleeding disorders 2011

Chronic HCV infection continues to be of significant clinical importance in patients with hereditary bleeding disorders. This guideline provides information on the recent advances in the investigation and treatment of HCV infection and gives GRADE system based recommendations on the management of the infection in this patient group.

Low body mass not vitamin D receptor polymorphisms predict osteoporosis in patients with inflammatory bowel disease

BACKGROUND

Osteoporosis is a recognized complication of inflammatory bowel disease (IBD). Aim To investigate the role of environmental factors and vitamin D receptor (VDR) variants on the prevalence of osteoporosis.

METHODS

DEXA scans and case note review were performed on 440 IBD patients from 1997 to 2006. All the IBD patients and 240 healthy controls were genotyped for VDR variants Taq-1 and Apa-1 using PCR-RFLP.

RESULTS

Osteoporosis and osteopenia rates were 15% and 18% for IBD, 16% and 18% for Crohn's disease (CD) and 13% and 19% for ulcerative colitis, respectively. On univariate analysis of the CD patients, low body mass index (BMI, <18.5) and smoking status (P = 0.008 and 0.005 respectively) were associated with osteoporosis and osteopenia. Low BMI was also associated with osteoporosis on multivariate analysis in CD (P = 0.021, OR 5.83, CI 1.31-25.94). No difference was observed between Taq-1 and Apa-1 VDR polymorphisms in IBD, CD, ulcerative colitis and healthy controls. However, CD males were more likely to carry the variant Taq-1 polymorphism than healthy controls males (P = 0.0018, OR 1.94, CI 1.28-2.92) and female CD patients (P = 0.0061, OR 1.60, CI 1.17-2.44).

CONCLUSIONS

In this well-phenotyped cohort of IBD patients, a relatively low prevalence of osteoporosis was observed. Low BMI was the only independent risk factor identified to be associated with osteoporosis.

Successful PCR amplification of genomic DNA from Cryptosporidium parvum oocysts extracted from a human faecal sample: a rapid and simple method suited for outbreak analysis

A method to extract genomic DNA from oocysts of Cryptosporidium parvum in human faecal material was developed and consisted of a simple alkali wash, freeze/boil technique. This method was simple, quick, sensitive, inexpensive and resulted in the production of genomic DNA which was free of PCR inhibitors and as such was a suitable template for the detection of C. parvum by various PCR amplification targets.

A select few: women and the National Research Council of Canada, 1916-1991

This paper explores the interrelationship of women and the National Research Council of Canada during the 1916-1991 period. Although women received 14% of the NRC fellowships and bursaries before 1931, they fared less well during and after the Depression. Based on information obtained from primary and secondary written sources as well as from interviews with both women and men employed by the NRC, the paper traces changing trends in employment practices and improved research opportunities for women scientists at the NRC.

MRSA pyomyositis complicating sickle cell anaemia

A patient being treated for sickle cell crisis developed swollen, painful, indurated, discoloured thighs after several days in hospital. Imaging revealed the presence of multiple small abscesses in the muscle and methicillin resistant Staphylococcus aureus (MRSA) was cultured from aspirated fluid. Pyomyositis usually occurs in association with damaged muscle and impaired host defences. Staphylococcus is the most frequent organism involved. It is not a common complication of sickle cell disease, although it may be under diagnosed. Availability of advanced imaging techniques facilitates early diagnosis of pyomyositis.

CMV viral load measurements in whole blood and plasma--which is best following renal transplantation?

BACKGROUND

Quantitative commercial assays for cytomegalovirus (CMV) detection have recently been developed. Their role in the management of patients after transplantation needs to be evaluated. Widespread use of these assays will allow for comparison of results between centers and meaningful interpretation of the significance of viral load measurements.

METHODS

Sequential samples from 52 patients after renal transplantation were tested in the murex hybrid capture assay (HCA) and the Roche Amplicor CMV DNA assay (QPCR) and correlated with the development of CMV disease. A comparison of viral loads in plasma and whole blood was also made.

RESULTS

Both assays were sensitive and detected all cases of CMV disease. The specificity and positive predictive value increased from 0.34 and 0.36 to 0.85 and 0.96 for the HCA and 0.37, 0.37 to 0.72 and 0.63 for the QPCR following a receiver operator curve analysis. Higher viral loads were measured using the HCA compared to the QPCR. Response to ganciclovir was associated with a greater than 80% reduction in viral load by HCA or greater than 70% using the QPCR.

CONCLUSIONS

Both assays were highly sensitive. By using a receiver operator curve analysis a cutoff viral load can be determined which maximizes the clinical utility of these assays.

ASW: a gene with conserved avian W-linkage and female specific expression in chick embryonic gonad

Vertebrates exhibit a variety of sex determining mechanisms which fall broadly into two classes: environmental or genetic. In birds and mammals sex is determined by a genetic mechanism. In mammals males are the heterogametic sex (XY) with the Y chromosome acting as a dominant determiner of sex due to the action of the testis-determining factor, SRY. In birds females are the heterogametic sex (ZW); however, it is not known whether the W chromosome carries a dominant ovary-determining gene, or whether Z chromosome dosage determines sex. Using an experimental approach, which assumes only that the sex-determining event in birds is accompanied by sex-specific changes in gene expression, we have identified a novel gene, ASW (Avian Sex-specific W-linked). The putative protein for ASW is related to the HIT (histidine triad) family of proteins. ASW shows female-specific expression in genital ridges and maps to the chicken W chromosome. In addition, we show that, with the exception of ratites, ASW is linked to the W chromosome in each of 17 bird species from nine different families of the class Aves.

The application of high permittivity piezoelectric ceramics to 2D array transducers for medical imaging

Two-dimensional (2D) array transducers have become of great interest in the last few years, in view of real-time volumetric ultrasonic imaging. The electrical matching between the high electrical impedance of elements and the standard cables and electronics is one of the key issues in 2D array design. The use of high-permittivity ceramics such as PNNZT either in bulk configuration or in 1-3 piezocomposites decreases the electrical impedance. In this paper, bulk samples of PNNZT and PZT ceramics are characterised, and results are compared. 2D array elements are then manufactured and their electrical impedances measured. Theoretical predictions of homogenisation models for 1-3 piezocomposites allow the simulation of the electroacoustic behaviour of 2D array elements. Results for both piezocomposite and bulk materials can be obtained. Calculations of the input impedance, the sensitivity and the bandwidth of the different configurations are compared and discussed. These results demonstrate the advantages of the PNNZT compositions over standard PZT.

PVDF reference hydrophone development in the UK-from fabrication and lamination to use as secondary standards

During the last 30 yrs, PVDF has been used extensively as a sensor material. Over this period, the GEC-Marconi Research Centre has developed a wide range of devices based on PVDF as a piezoelectric transducer material. The ability to create laminated structures has led to an enhancement in performance and has allowed innovative designs to be realized. This paper describes the development of the laminated PVDF structure and its benefits, such as increased sensitivity and improved signal to noise ratio. Examples of devices utilizing the lamination process are given in the form of both a bilaminar-shielded membrane hydrophone and a PVDF sonar hydrophone. Performance properties of both types of hydrophones are presented along with a discussion of their use as secondary standard hydrophones at the National Physical Laboratory (NPL).

Use of molecular assays in diagnosis and monitoring of cytomegalovirus disease following renal transplantation

We compared two commercial molecular assays (the Murex Hybrid Capture CMV DNA assay [HCA], version 2, and the Roche Amplicor plasma PCR assay) with a standard shell vial assay in detecting and predicting cytomegalovirus (CMV) disease in a group of renal transplant patients and assessed the role of viral load measurements (using the HCA) in their management. The sensitivity of the HCA and Amplicor assay in terms of disease detection was 100%, compared to 71% for the shell vial assay. Both the HCA and the PCR assay detected all cases of disease, at medians of 11 and 12.5 days before the onset of symptoms, respectively. Significantly higher viral loads were detected in those patients with symptoms (7.9 x 10(5) copies/ml) than in patients without symptoms (7.9 x 10(4) copies/ml; P < 0.0001). There was also a trend towards higher viral loads in those patients with primary infections (7.8 x 10(5) copies/ml) than in those patients with reactivations of CMV disease or reinfections. Successful treatment with ganciclovir was associated with a >90% reduction in viral load. Both of these new assays are sensitive and easy to use. A comparison of accurate quantitation is also useful in monitoring responses to antiviral therapy.

Perceptions of care and services by the clients and families: a personal experience

This study was initiated in response to a provincial mental health policy emphasizing the primacy of the person and the hospital's decision to adopt total quality management. The objective of the project was to learn more about how clients and families viewed the care and services received during a psychiatric admission. Their perceptions were elicited through seven focus groups including multiple admission (3) clients and families of single and multiple admission clients (2 each). Group sessions were tape-recorded, transcribed and analysed for themes. Three major themes were identified: quantity and quality of care, individuality and partnership. Both positive and negative comments were made within each of these themes, but two major areas for improvement were continuity of care and the environment. The findings are being used to change practices within the Department of Psychiatry.

Effects of H-7 on the iris and ciliary muscle in monkeys

OBJECTIVES

To determine the effects of H-7 on (1) iris and ciliary muscles (CMs) in living monkeys; (2) isolated monkey CM strips; (3) actomyosin contractility in cultured Swiss 3T3 cells.

METHODS

(1) Pupillary diameter (calipers) and accommodation (refractometer) in living monkeys were measured after topical, intracameral, or intravitreal administration of H-7 followed by systemic pilocarpine hydrochloride. (2) Pilocarpine-induced contraction of isolated monkey CM strips following administration of H-7 was measured in a perfusion chamber. (3) Actomyosin contractility in Swiss 3T3 cells cultured on thin silicone rubber film was determined by measuring cell-induced film wrinkles before and after administration of H-7.

RESULTS

Topical H-7 prevented anesthesia-induced miosis but did not affect resting refraction. Intracameral or intravitreal H-7 dilated the pupil and inhibited miotic but not accommodative responses to pilocarpine. H-7 inhibited pilocarpine-induced contraction of isolated monkey CM strips and reduced Swiss 3T3 cell contraction.

CONCLUSIONS

H-7 inhibits actin-based contractility in non-muscle cells and in monkey iris sphincter and CM. Under our in vivo experimental conditions, the effect on the iris predominates over that on the CM.

Modeling of highly loaded 0-3 piezoelectric composites using a matrix method

A model previously developed for pure 0-3 connectivity piezocomposites has been extended to 3-3 connectivity. This matrix method allows the prediction of the effective electroelastic moduli of a piezocomposite according to its connectivity. It is used to optimize composite performance by choosing the optimal constituents for each phase. A simple combination of the results for 0-3 and 3-3 connectivities allows the effective proportion of 3-3 connectivity to be defined in highly loaded 0-3 piezocomposites. This theoretical analysis has been used to evaluate effective proportions of 3-3 connectivity in five composite samples. The values obtained are shown to be a function of the ceramic volume fraction and fabrication process. The results of this study were used to optimize the fabrication process.

Bladder epithelial oxygen tension--a new means of monitoring regional perfusion? Preliminary study in a model of exsanguination/fluid repletion

OBJECTIVE

To assess whether monitoring of bladder epithelial oxygen tension (BEOT) would provide an indication of regional (renal) organ perfusion in an exsanguination/fluid repletion animal model.

DESIGN

Prospective non-randomized laboratory study.

SETTING

Research laboratory.

INTERVENTIONS

Eight anaesthetised, spontaneously breathing Sprague-Dawley male rats weighing approximately 200 g were instrumented. They received 1-ml aliquots of fluid until no further haemodynamic improvement was seen, followed by removal of 1-ml aliquots of blood until renal blood flow fell by 50%. The animal was then resuscitated with repeated 1 to 2-ml aliquots of fluid until no further improvement was achieved and, finally, progressively exsanguinated to cardiovascular collapse.

MEASUREMENTS AND RESULTS

A continuous Clark-type oxygen electrode lying in contact with the inside wall of the bladder measured changes in BEOT during these exsanguination and fluid repletion manoeuvres. Changes in BEOT closely mirrored both systemic (blood pressure and aortic blood flow) and regional (renal blood flow) haemodynamic changes. A direct correlation existed between percentage change in BEOT and base deficit, and an indirect correlation was seen with arterial oxygen tension.

CONCLUSIONS

Measurement of BEOT may be a useful and relatively non-invasive means of monitoring regional organ perfusion. Further studies are warranted.

Endothelin subtypes: effect on isolated rhesus monkey ciliary muscle

The effects of endothelin (ET)-1, ET-2, ET-3 and sarafotoxin S6C on the contractile response in the longitudinal and coronal vectors of the isolated rhesus monkey ciliary muscle were studied. Fresh ciliary muscle strips from young and middleaged rhesus monkeys were mounted in an apparatus capable of monitoring contractile force simultaneously in the two vectors. The responses to the ET compounds were measured and compared to those produced with 1 microM carbachol. ET-1 produced contractions of up to 15% of the near-maximum response to carbachol in both vectors of 66% of ciliary muscle strips studied. In responsive strips, the maximal ET-1 induced contraction was approximately equal in both vectors, but the longitudinal vector was approximately 5-fold more sensitive than the circular. All ciliary muscle strips responded reproducibly to carbachol. None of the other ET compounds tested had any effect, suggesting that the ETA receptor may predominate in rhesus monkey ciliary muscle. Because ET-1 induces only weak and interindividually variable contraction in isolated rhesus monkey ciliary muscle strips, ET-1's enhancement of outflow facility with only minimal induction of accommodation in the living monkey may be due to effects directly on the trabecular meshwork. However, the 5-fold greater potency of ET-1 in the longitudinal compared to the circular contractile vector may indicate that selective contraction of the longitudinal portion of the ciliary muscle with consequent deformation of the trabecular meshwork but not the lens is also involved.

Prostaglandin F2 alpha effects on isolated rhesus monkey ciliary muscle

PURPOSE

The effects of prostaglandin (PG)F2 alpha on the contractile response in the longitudinal and coronal vectors of the isolated rhesus monkey ciliary muscle were studied.

METHODS

Fresh rhesus monkey ciliary muscle strips from young and middle-aged animals were mounted in an apparatus capable of monitoring contractile force simultaneously in the two vectors. The responses to PGF2 alpha were measured and compared to those produced with 1 microM carbachol.

RESULTS

PGF2 alpha consistently relaxed the carbachol precontracted ciliary muscle in a dose-dependent manner with equal potency and efficacy in both vectors, but it did not alter the tone of muscle strips at resting tension.

CONCLUSIONS

The relaxation of precontracted ciliary muscle by PGF2 alpha may help explain how a single topical dose of this prostanoid increases uveoscleral outflow and antagonizes resting myopia in the living monkey.

Effects of timolol, terbutaline and forskolin on IOP, aqueous humour formation and ciliary cyclic AMP levels in the bovine eye

We have studied the effects of terbutaline, timolol, forskolin and 8-bromo cyclic AMP on aqueous humour formation, intraocular pressure and on ciliary epithelial cyclic AMP levels, either in presence or in absence of IBMX, using the bovine isolated arterially perfused eye, excised ciliary processes and cultured ciliary epithelium. Both terbutaline, a beta-adrenoceptor agonist, and timolol, a beta-adrenoceptor antagonist, caused significant reduction in aqueous humour formation and intraocular pressure but produced no effect on ciliary epithelial cyclic AMP content in the absence of IBMX. Even a three times higher dose of terbutaline was entirely ineffective in producing any effect on ciliary cyclic AMP in the perfused eye. On the other hand, terbutaline at the IOP-reducing dose, produced a significant increase in cyclic AMP when injected after 30 min perfusion with IBMX. Incubation of excised ciliary processes or cultured ciliary epithelial cells with terbutaline (10(-6) to 10(-4) M) produced concentration-dependent increases in cyclic AMP, in both tissues, even in the absence of IBMX. Forskolin, which stimulates cyclic AMP synthesis without interacting with cell surface receptors, was found to produce highly significant increases in ciliary cyclic AMP content both in presence and in absence of IBMX but had no effect on aqueous humour formation in the isolated eye. IBMX perfused at concentrations of 1 mM or 10 microM had no effect on basal levels of ciliary cyclic AMP but the 1 mM concentration produced a marked and significant reduction in IOP. Direct application of 8-bromo cyclic AMP, a cell permeable analogue, more resistant to hydrolysis by phosphodiesterases, had also no effect on aqueous humour formation in the perfused eye. It is concluded that in the bovine arterially perfused eye, the correlation between the aqueous humour formation rate and ciliary epithelial cyclic AMP content is unclear.

Cerebral arteriovenous malformations in children

The treatment of cerebral arteriovenous malformations (AVM) or vascular anomalies are challenging neurosurgical procedures for an anaesthetist. Large AVMs are uncommon in children. Only 18% of AVMs become symptomatic before the age of 15 yr. This series reviews the experience at this institution during the period of 1982 to 1992. The symptoms at the time of presentation are varied and include haemorrhage (50%), seizures and hydrocephalus (36%) or congestive cardiac failure (18%). Symptoms of congestive heart failure predominate in the newborn whilst neurological symptoms, such as stroke, seizures or hydrocephalus occur more commonly in infants and older children. Approximately one third of AVMs in childhood present acutely. Radiological investigations, e.g., CT scan, MRI and cerebral angiography are essential to identify the precise location of the lesion. Therapeutic intervention in the acute presentation may involve craniotomy for evacuation of haematoma and treatment of increased intracranial pressure (ICP). Control of seizures and congestive heart failure may take priority and allow time to plan the elective procedures of embolization and surgical excision of the AVM. Operative intervention is hazardous and peroperative complications can be expected in more than 50% of patients. The morbidity and mortality associated with cerebral AVM are high, especially in infants who present in the neonatal period with congestive cardiac failure. The overall mortality in this series was 20%. Children presenting with intracranial arteriovenous malformations require a multidisciplinary approach. The successful management of anaesthesia either for embolization or surgical resection necessitates an understanding of the disciplines of paediatric and neuroanaesthesia. Special care and specific attention to detail may contribute to reduce the high morbidity and mortality encountered in these compromised children.

Awake intubation increases intracranial pressure without affecting cerebral blood flow velocity in infants

Tracheal intubation is frequently required in neonatal anaesthetic practice. Awake intubation is one method of securing the airway and in certain circumstances, for many anaesthetists, can be preferable to intubation following induction of anaesthesia. Previous studies have inferred that the elevation in anterior fontanelle pressure observed during tracheal intubation in neonates was caused by an increase in cerebral blood flow although it was never measured. In this study, direct methods were used to observe changes in the cerebral circulation. Thirteen neonates, ASA I to III (E), aged from 1 to 34 days of age were studied. Patients were randomized to receive either tracheal intubation awake or following induction of anaesthesia with thiopentone 5 mg.kg-1 and succinylcholine 2 mg.kg-1. Heart rate, systolic arterial blood pressure, anterior fontanelle pressure, cerebral blood flow velocity (using transcranial Doppler sonography) and oxygen saturation were recorded at the following intervals: baseline (not crying), after intravenous atropine 0.02 mg.kg-1, during laryngoscopy, immediately after insertion of the endotracheal tube, one and five minutes later. The use of atropine masked the cardiovascular responses to intubation. Whereas the change in anterior fontanelle pressure from baseline was different between the groups (P < 0.05), the cerebral blood flow velocity variables were not. The rise in anterior fontanelle pressure seen in the awake group may be attributed to a reduction of the venous outflow from the cranium thereby increasing cerebral blood volume and subsequently the intracranial pressure.

The bovine arterially-perfused eye: an in vitro method for the study of drug mechanisms on IOP, aqueous humour formation and uveal vasculature

A method is reported in which the isolated bovine eye is perfused through a long posterior ciliary artery with buffered physiological saline, to provide simultaneous monitoring of drug effects on intraocular pressure (IOP), vascular resistance and the condition of the blood-aqueous barrier. With perfusion under constant pressure of 45 mm Hg, perfusate flows at 1.64 +/- 0.12 ml.min-1 (mean +/- SEM) and IOP is 7.26 +/- 0.16 mm Hg. Applying a constant flow rate of 2.25 ml.min-1, IOP averages 10.19 +/- 0.32 mm Hg and in both cases this can be maintained for around 2h. Increasing the perfusion flow rate from 1.5 to 3.5 ml.min-1 produces a 76% rise in perfusion pressure but IOP increases only insignificantly (< 10%). The inclusion in the perfusion fluid of dextran and albumin to maintain oncotic pressure similar to that of plasma makes no difference to the IOP achieved and does not affect the leakiness of the barrier. The preparation shows a net consumption of oxygen, supporting the hypothesis that the aqueous humour formed is secreted by active transport processes. Timolol (in bolus doses of 1-300 nmol) injected into the perfusing fluid is shown to induce a dose-dependent fall in IOP within 5 min, reaching a steady state within 40 min. Timolol, however, causes no significant change in vascular resistance, whether this is measured as perfusion flow rate under constant pressure or as perfusion pressure at constant flow rate, nor does it alter the permeability of the barrier. Other beta-blockers such as oxprenolol and betaxolol also induce dose-dependent decreases in IOP. By applying a fluorescein dilution technique, it is found that the aqueous formation rate (K(out) = 0.0046 min-1, or 12.9 microliters.min-1) is also reduced by timolol and, in a dose-dependent manner, by the new carbonic anhydrase inhibitor, MK-927. The bovine perfused eye offers a useful method for studying the mechanisms of action of drugs on IOP and aqueous humour formation, in isolation from the complicating influences of the CNS and the cardiovascular system and without the necessity to kill animals for experimental purposes.

Multimodality approach to staging renal cell carcinoma

Renal imaging has dramatically improved since the introduction of ultrasound (US), computed tomography (CT), and most recently magnetic resonance (MR) imaging. US and MR imaging are ideal for patients with compromised renal function preventing administration of iodinated contrast material or those who have experienced reactions to contrast. Staging errors occur due to limitations in assessing microscopic tumor invasion of the renal capsule and perinephric fat, detecting metastatic deposits in normal sized lymph nodes and differentiating inflammatory hyperplastic lymph nodes from neoplastic ones. These limitations are shared by US, CT, and MR imaging. Vascular invasion by tumor can be evaluated by all imaging modalities including venography. The advantages and limitations of each examination will be presented.

Haemodynamic effects and uptake of enflurane in patients undergoing cardiac surgery: good versus poor myocardial function

We measured haemodynamic effects and uptake of enflurane in patients undergoing cardiac surgery utilizing a standard anaesthetic technique of fentanyl 15 mcg/kg nitrous oxide 50%/enflurane 1%. We divided 22 patients preoperatively into two groups according to standard criteria: good and poor myocardial function. Regression lines could be drawn illustrating the relationship of cardiac output and uptake (at 1 minute: r = -0.56, P less than 0.01; at 5 minutes: r = -0.43, P less than 0.05; at 30 minutes: r = -0.31, P = 0.08). Although patients with poor myocardial function had decreased uptake of enflurance (approximately 10-20%), this did not reach statistical significance. Fentanyl/nitrous oxide/enflurane anaesthesia provided stable haemodynamics, even in patients with poor myocardial function. Both groups had a shunt fraction of approximately 10% and an arterial: end-tidal carbon dioxide difference of approximately 3-4 mmHg.