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J Pereira

Publications and source records attributed to J Pereira.

At least 19 recordsLinked to original sources
PubMed2001

Strategies to manage the adverse effects of oral morphine: an evidence-based report.

Successful pain management with opioids requires that adequate analgesia be achieved without excessive adverse effects. By these criteria, a substantial minority of patients treated with oral morphine (10% to 30%) do not have a successful outcome because of (1) excessive adverse effects, (2) inadequate analgesia, or (3) a combination of both excessive adverse effects along with inadequate analgesia. The management of excessive adverse effects remains a major clinical challenge. Multiple approaches have been described to address this problem. The clinical challenge of selecting the best option is enhanced by the lack of definitive, evidence-based comparative data. Indeed, this aspect of opioid therapeutics has become a focus of substantial controversy. This study presents evidence-based recommendations for clinical-practice formulated by an Expert Working Group of the European Association of Palliative Care (EAPC) Research NETWORK: These recommendations highlight the need for careful evaluation to distinguish between morphine adverse effects from comorbidity, dehydration, or drug interactions, and initial consideration of dose reduction (possibly by the addition of a co analgesic). If side effects persist, the clinician should consider options of symptomatic management of the adverse effect, opioid rotation, or switching route of systemic administration. The approaches are described and guidelines are provided to aid in selecting between therapeutic options.

Administration, Oral↗
PubMed2001

Equianalgesic dose ratios for opioids. a critical review and proposals for long-term dosing.

Clinicians involved in the opioid pharmacotherapy of cancer-related pain should be acquainted with a variety of opioids and be skilled in the selection of doses when the type of opioid or route of administration needs changing. The optimal dose should avoid under-dosing or overdosing, both associated with negative outcomes for the patient. Although equianalgesic dose tables are generally used to determine the new doses in these circumstances, the evidence to support the ratios indicated in these tables largely refers to the context of single dose administration. The applicability of these ratios to the setting of chronic opioid administration has been questioned. A systematic search of published literature from 1966 to September 1999 was conducted to critically appraise the emerging evidence on equianalgesic dose ratios derived from studies of chronic opioid administration. There were six major findings: 1) there exists a general paucity of data related to long-term dosing and studies are heterogeneous in nature; 2) the ratios exhibit extremely wide ranges; 3) methadone is more potent than previously appreciated; 4) the ratios related to methadone are highly correlated with the dose of the previous opioid; 5) the ratio may change according to the direction the opioid switch; and 6) discrepancies exist with respect to both oxycodone and fentanyl. Overall, these findings have important clinical implications for clinicians and warrant consideration in the potential revision of current tables. The complexity of the clinical context in which many switches occur must be recognized and also appreciated in the design of future studies.

Analgesics, Opioid↗
PubMed2001

Complementary effects of Mediterranean diet and moderate red wine intake on haemostatic cardiovascular risk factors.

OBJECTIVES: To compare the effect of alcohol-free Mediterranean-type diet (MD) and high-fat diet (HFD) on plasma concentration of emergent haemostatic cardiovascular risk factors (HCVRF). Also, to test if red wine supplementation modifies HCVRF, independent of diet. DESIGN, SUBJECTS AND INTERVENTION: Controlled prospective intervention study. Two groups, each of 21 healthy male university students (22+/-3.4 y), received either MD or HFD for 90 days. Between days 30 and 60, both diets were supplemented with 240 ml/day of red wine. Baseline and T30, T60 and T90-day samples were drawn. No drop out from the study was observed. SETTING: University campus and outpatient nutrition clinic. RESULTS: Volunteers on HFD at T30 had increases in pro-coagulants fibrinogen (22%), factor VIIc (9%), and factor VIIIc (4%), and decreases in natural anticoagulants antithrombin III (3%), protein C (11%) and protein S (6%) and of 20% in plasminogen activator inhibitor-1. At the same time, individuals on MD had increases in fibrinogen (4%), antithrombin III (5%), protein C (3%), protein S (2.7%), and decreases in factor VIIIc (9%), and plasminogen activator inhibitor-1 (21%). After adjusting by baseline values, MD was associated with lower plasma fibrinogen (P=0.03), factor VIIc (P=0.034) and factor VIIIc (P=0.0057) and with higher levels of protein S (P=0.013). Red wine supplementation, in both diets, resulted in decreased plasma fibrinogen (P=0.001) and factor VIIc (P=0.05), and increased tissue plasminogen activator antigen (P=0.01) and plasminogen activator inhibitor-1 antigen (P=0.0003). Wine consumption was also associated with significantly (P=0.01) divergent effects on antithrombin III: it decreased by 10% in individuals on HFD but increased slightly in those on MD. No effects of diet or wine were detected in plasma protein C and C-reactive protein. CONCLUSION: MD and moderate consumption of red wine have complementary, mostly beneficial effects on HCVRF.

Adult↗
PubMed2001

Increased activation of protein C, but lower plasma levels of free, activated protein C in uraemic patients: relationship with systemic inflammation and haemostatic activation.

Chronic renal failure (CRF) courses with both systemic inflammatory reaction and haemostatic activation. We explored the relationship of these processes with plasma levels of free, activated protein C (APC) and complexes of APC with its inhibitors in patients with CRF under conservative treatment. Plasma concentrations of inflammatory cytokines [tumour necrosis factor alpha (TNFalpha) and interleukin 8], acute-phase proteins (C-reactive protein, fibrinogen, alpha1-anti-trypsin and von Willebrand factor), and markers of haemostatic activation (thrombin-anti-thrombin complexes, plasmin-anti-plasmin complexes, and fibrin and fibrinogen degradation products) were higher in patients than in controls. Inflammatory and haemostatic markers were significantly and positively correlated. Total plasma APC and APC:alpha1-anti-trypsin (alpha1AT) complexes were 44% and 75% higher in patients than in controls (P = 0.0001), whereas free APC was 20% lower (P < 0.015). No significant difference was observed in APC:protein C inhibitor (PCI) complexes between both groups. The free/total APC ratio was significantly lower in patients than in controls (P < 0.0001). Total plasma APC and APC:alpha1AT were positively correlated with activation markers of haemostasis and acute-phase proteins, whereas free APC was inversely correlated with plasma levels of creatinine, acute-phase proteins and fibrin degradation products (FnDP). Systemic inflammation and activation of haemostasis are interrelated processes in CRF. APC generation was increased in response to elevated thrombin production, but the inflammatory reaction, associated with increased synthesis of alpha1AT, reduced its anticoagulant effect. Lower free plasma APC in CRF may be pathogenically associated with atherothrombosis, a major cause of death in this disease.

Adult↗
PubMed2001

Effect of angiotensin-converting enzyme inhibition on renal filtration surface area in hypertensive rats.

BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitor treatment leads to protective effects on the cellular structure of the glomerulus and the kidney. The aim of this study was to determine whether ACE inhibition increases renal filtration surface area in the spontaneously hypertensive rat (SHR). METHODS: SHR were treated with the ACE inhibitor perindopril at a high dose (3 mg/kg/day) or a low dose (0.1 mg/kg/day) during the period of hypertension development, from 7 to 14 weeks of age. Some animals were treated concomitantly with the bradykinin B2 receptor antagonist, S16118. Tail-cuff systolic blood pressure and body weights were measured twice weekly. At termination of treatment, glomerular number and volume, length, and surface area of glomerular capillaries and renal filtration surface area were estimated using unbiased stereological techniques. RESULTS: There were significant dose-related reductions in blood pressure with high- and low-dose perindopril treatment. Neither low- nor high-dose perindopril treatment had any effect on glomerular number or size or glomerular capillary length and surface area. Hence, there was no significant difference in total renal filtration surface area between any of the experimental groups (8721 +/- 610 mm2 in untreated SHR and 7879 +/- 338 mm2 and 8767 +/- 437 mm2 in the low and high dose perindopril-treated groups, respectively). Coadministration of the bradykinin antagonist did not affect any of the glomerular parameters. CONCLUSIONS: ACE inhibition during the period of hypertension development does not lead to an enhanced glomerular capillary growth or increases in total renal filtration surface area in this model.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2001

Suprafascial dissection of the radial forearm flap and donor site morbidity.

A cutaneous free radial forearm flap was harvested from 25 patients using a suprafascial dissection technique. The donor site was managed with either a full or split thickness skin graft and a negative pressure wound dressing. The incidence of initial complete graft take was 96% at day 5 and 100% by 1 month. There was 100% early and complete graft take in the full thickness group but one area of partial loss in the split thickness group. This area of graft loss represented less than 0.5% of the total grafted area in this series. The mean time to wound healing was 14 days. There were no cases of tendon exposure or delayed healing. The suprafascial dissection creates a superior graft recipient bed. When combined with the negative pressure wound dressing technique it ensured early and complete graft take.

Adult↗
PubMed2001

Depression with psychomotor retardation: diagnostic challenges and the use of psychostimulants.

A patient with advanced pancreatic cancer is presented to demonstrate the clinical challenge of diagnosing depression in palliative care. The conundrum related to the relative roles of somatic and psychological symptoms in screening or diagnosing depression in these patients is illustrated and discussed. There is no clear consensus on how to apply diagnostic criteria for diagnosing depression in these patients. Although an approach that focuses on the psychological symptoms is often suggested, it appears that somatic criteria cannot be entirely excluded. The case also highlights the use of methylphenidate to treat palliative care patients. As compared to traditional antidepressants that may take as long as 6-8 weeks to have a full effect, they offer the advantage of onset of action within a few days. This is especially helpful in patients with limited life expectancies. They appear to be particularly advantageous where psychomotor retardation is a main feature of the depression. The patient discussed demonstrated an observed and self-reported improvement of mood and psychomotor retardation following the initiation of psychostimulant treatment. Larger, controlled trials, using specified criteria to diagnose depression, are warranted to elucidate the role of psychostimulants in treating depression in palliative care patients.

Aged↗
PubMed2001

Integrating the "new" with the "traditional": an innovative education model.

In 1998 the Faculty of Pharmacy and Pharmaceutical Sciences at the University of Alberta, Canada, introduced a new elective semester course entitled "The Pain Module" for pharmacy students in their final year of undergraduate training. The aim was to build on the existing theoretical content related to areas such as pharmacology and therapeutics and to generate opportunities for skill and attitude development, including those related to the management of cancer-related pain. Traditional formats such as classroom-based seminars were integrated with innovative methods such as computer-mediated discussions and conferencing (CMC) and academic bus rounds. The CMC component of the course served to provide continuity of discussion between weekly classroom discussions, gave students access to content experts on an ongoing basis and furthered learning initiated in the classroom. Students were given the opportunity to meet palliative care patients being cared for at home and in hospices. A total of 21 students participated in all the course activities. By the end of the course, there appeared to be a greater appreciation for end-of-life care issues. This highlights the need to incorporate end-of-life care into the undergraduate curriculum of disciplines other than medicine and nursing. Evaluation of the course identified several benefits and limitations of CMC. There was increased access to content experts and increased interaction between students. Limitations of CMC included increased time commitments and an open-ended nature that was uncomfortable for some learners. Other benefits and limitations are described further in this article. Future attempts at integrating new instructional technologies should be systematically evaluated.

Computer-Assisted Instruction↗
PubMed2001

Reflecting on the work of palliative care.

Caring for the terminally ill and their families is a unique experience. The experiences of our everyday work shape and transform us as individuals and as teams in ways that are sometimes subtle and unrecognizable and other times quite overt and apparent. Yet some of us as palliative care professional caregivers seldom take the time to stop and reflect on the work we do and how it impacts us, both personally and collectively as a team. In this article we share our experiences with a multidisciplinary "Reflection" Group.

Humans↗
PubMed2001

Percutaneous mechanical mitral commissurotomy performed with a Cribier's metallic valvulotome. Initial results.

OBJECTIVE: To evaluate the immediate results of percutaneous mechanical mitral commissurotomy. METHODS: Thirty patients underwent percutaneous mechanical mitral commissurotomy performed with a Cribier's metallic valvulotome from 8/11/99 to 2/4/00. Mean age was 30.7 years, and 73.3% were women. With regards to functional class, 63.3% were class III, and 36.7% were class IV. The echocardiographic score had a mean value of 7.5+/- 1.8. RESULTS: The mitral valve area increased from 0.97+/-0.15cm2 to 2.16+/-0.50cm2 (p>0.0001). The mean diastolic gradient decreased from 17.9+/-5.0mmHg to 3.2+/-1.4mmHg. The mean left atrial pressure decreased from 23.6+/-5.4mmHg to 8.6+/-3.1mmHg, (p>0.0001). Systolic pressure in the pulmonary artery decreased from 52.7+/-18.3mmHg to 32.2+/-7.4mmHg. Twenty-nine cases were successful. One patient developed severe mitral regurgitation. Interatrial septal defect was observed and one patient. One patient had cardiac tamponade due to left ventricular perforation. No deaths occurred. CONCLUSION: This method has proven to be safe and efficient in the treatment of rheumatic mitral stenosis. The potential advantage is that it can be used multiple times after sterilization, which decreases procedural costs significantly.

Adult↗
PubMed2001

Palliative care on the net: an online survey of health care professionals.

A survey was conducted to explore Internet use by palliative care health professionals (HCP). The survey was placed on the World Wide Web with an underlying database, and palliative care HCP were invited to participate via a palliative-care-related website, listserv, and newsletter. A total of 417 evaluable responses were received over a four-month period. Of these, 36% indicated they were from physicians and 30% from nurses, a third of respondents were practicing palliative care full time. Although 63% of respondents were from North America, regions from all over the world were represented. Eighty-eight percent of respondents were searching the Internet for clinical information, 80% were using email, 69% were accessing online medical journals, and 59% were subscribers to a palliative-care-related listserv or newsgroup. This survey illustrates the global outreach of the Internet and draws attention to the growing interest in the use of the Internet for education, research, and clinical use. Further development of online resources should address the needs of users. Evaluation of these resources is called for.

Adult↗
PubMed2001

Brain-invasive meningioma in a 16-month-old boy.

A previously well 16-month-old boy presented to Sydney Children's Hospital with generalised seizures. There was no history of neurofibromatosis and no family history. Imaging revealed a well-demarcated, frontal intracranial mass at the grey-white matter junction with surrounding oedema. At operation, the tumour was adherent to the underlying brain on its deep aspect but superficially connected to the dura. There was an associated peritumoural cyst. The tumour was biopsied for intra-operative frozen section opinion and excised in its entirety. The specimen consisted of a 25 x 25 x 17 mm nodule of firm cream tissue and separate fragments. Histologically, the tumour was a meningioma with frequent mitoses, necrosis and brain invasion. Optimal treatment, in view of the recurrence risk, includes complete excision and postoperative irradiation. The latter was deferred because of the young age. At follow-up at 26 months, the child was well and free of disease on MRI scan. Paediatric meningiomas are rare, with very few brain-invasive examples in reported series. In infants and young children, few meningiomas have been reported. There are several notable differences between meningiomas in children and adults. This report illustrates these differences.

Brain Neoplasms↗
PubMed2001

Use of Indermil tissue adhesive for closure of superficial skin lacerations in children.

BACKGROUND: The aim of this study was to assess the use of tissue adhesive for paediatric wound closure in a minor injuries environment. METHODS: A n-butyl 2-cyanoacrylate adhesive formulation was used for the closure of traumatic skin lacerations in 56 children. RESULTS: Tissue adhesive succeeded in approximating skin margins in all cases. No episodes of wound dehiscence were experienced. There were no incidences of wound infection. CONCLUSIONS: This study indicates that this form of tissue adhesive can safely and effectively be utilised for traumatic superficial skin closure in children.

Adolescent↗
PubMed2000

Cardiovascular risk factors in vegetarians. Normalization of hyperhomocysteinemia with vitamin B(12) and reduction of platelet aggregation with n-3 fatty acids.

Hyperhomocysteinemia in association with vitamin B(12) deficiency, and increased platelet aggregation, probably due to dietary lack of n-3 fatty acids, constitute cardiovascular risk factors frequently observed in vegetarians. We tested if administration of vitamin B(12) normalizes the concentration of total plasma homocysteine, and if intake of eicosapentaenoic (20:5n-3) and docosahexaenoic (22:6n-3) fatty acids modulates platelet function in a population of lactoovovegetarians. One week after a single intramuscular injection of cyanocobalamin (10000 microg) in 18 individuals, serum vitamin B(12) increased from 149+/-63 pg/mL to 532+/-204 pg/mL (p<0.0001) and total tHcy dropped from 12.4+/-4.7 to 7.9+/-3.1 micromol/L (p<0. 0001). Ten of fourteen of these vegetarians completed an 8-week supplementation with 700 mg/day of each eicosapentaenoic and docosahexaenoic acids. Increased incorporation of these fatty acids into plasma lipids was observed in all of them, together with a significant reduction in maximum percentage or slope of platelet aggregation with all the agonists tested (ADP, epinephrin, collagen, arachidonic acid). No significant change in bleeding time was observed after n-3 fatty acid trial. Supplementation with vitamin B(12) and n-3 fatty acids corrects hyperhomocysteinemia and reduces platelet reactivity to agonists in vegetarians. Whether this supplementation improves the already reduced cardiovascular morbidity and mortality associated with vegetarian diet has yet to be demonstrated.

Adult↗
PubMed2000

Estuarine and habitat-related differences in growth rates of young-of-the-year winter flounder (Pseudopleuronectes americanus) and tautog (Tautoga onitis) in three northeastern US estuaries.

Instantaneous growth rates of young-of-the-year winter flounder Pseudopleuronectes americanus (Walbaum) (12.0-60.4 mm standard length, SL) and tautog Tautoga onitis (Linnaeus) (21.4-73.8 mm total length, TL) from three estuarine systems in New Jersey (Great Bay-Little Egg Harbor and Navesink River) and Connecticut (Hammonasset River) were used in an attempt to assess the relative quality of selected nominal habitats. A series of short-term field caging experiments were conducted during 1994 and 1995 in: macroalgae (primarily, Ulva lactuca), eelgrass (Zostera marina), unvegetated areas adjacent to macroalgae and eelgrass and tidal creeks in Spartina dominated marsh. Growth rates varied with habitat, estuary and year. Comparisons across nominal habitats within and among estuaries did not show any one habitat with consistently higher growth, and growth was relatively independent of whether a habitat was vegetated or adjacent to vegetation. The growth rates of winter flounder and tautog from the Hammonasset River were not different among habitats in either year of the study. In the Great Bay-Little Egg Harbor, both winter flounder and tautog had higher growth rates in macroalgae with growth in eelgrass varying significantly between years. Conversely, in the Navesink River both species had higher growth rates in eelgrass. Environmental changes associated with temperature and dissolved oxygen appeared to influence growth rates. Winter flounder growth rate and survival was depressed in tidal marsh creeks in the three estuaries and in vegetated macroalgae habitats in the Navesink River where dissolved oxygen levels were often very low (<2 mgl(-1)) for extended periods. In summary, the growth rates of the young-of-the-year of these two species varied temporally and were dependent on the interaction of both the specific estuary and habitat in which the experiments took place. Further, habitat quality, as defined by relative growth rate, was difficult to evaluate because it can be variable and nominal habitat designations are often not sufficient to define the boundaries of a species habitat requirements.

Journal Article↗
PubMed2000

The radiologist says malrotation: does the surgeon operate?

The management of malrotation when it is an incidental finding is unclear. This retrospective study reports an analysis of radiological and operative findings in a series of 71 patients. There were no deaths. We report a false-positive rate of 15% for upper gastrointestinal contrast studies reported as showing malrotation. Our findings and a review of the literature demonstrate that in the asymptomatic child over 2 years of age, the evidence supporting mandatory correction of malrotation is weak.

Child, Preschool↗