Thesis (M.D.S.)--University of Hong Kong, 2000. / Includes bibliographical references (leaves 138-164).

Thesis (M.D.S.)--University of Hong Kong, 2000. / Includes bibliographical references (leaves 138-164). Also available in print.

Made available in DSpace on 2014-08-13T14:50:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-10Bitstream added on 2014-08-13T18:00:47Z : No. of bitstreams: 1 000753372.pdf: 1420006 bytes, checksum: 95cc4ca0aa76621c61d5f3a39a79e3b1 (MD5) / A Hemodiálise Prolongada (HDP) é opção de suporte renal para pacientes críticos com lesão renal aguda (LRA) e instabilidade hemodinâmica. O tempo de HDP pode variar de 6 a 18h e as intercorrências mais comuns são hipotensão e coagulação de sistema. Este foi um estudo prospectivo do tipo ensaio clínico com objetivo de avaliar e comparar as intercorrências dialíticas ocorridas durante diferentes durações de HDP (sessões de 6 e 10h) em pacientes críticos com LRA. Foram incluídos pacientes maiores de 18 anos com LRA associada à sepse, internados em Unidade de Terapia Intensiva, em uso de noradrenalina na dose de 0,3 a 0,7 ug/kg/min. Os pacientes foram alocados em dois grupos de modo aleatório, o grupo 1 (G1) foi submetido a sessões de 6 h e o grupo 2 (G2) a sessões de 10h. Para análise dos dados foi utilizado o programa SAS for Windows, versão 9.2. As comparações das variáveis contínuas entre os grupos foram realizadas através do teste t Student e teste de Mann-Whitney, e para as variáveis categóricas, os testes do Qui-Quadrado e teste exato de Fisher. Para as comparações das variáveis por sessões foi utilizado o modelo misto de análise de medidas repetidas no tempo com ajuste para Tukey. Foi considerado o nível de significância de 5%. Setenta e cinco pacientes foram tratados com 195 sessões de HPD durante 18 meses consecutivos. A idade média foi de 61,8±15,1 anos, predomínio de sexo masculino (70,6%), o principal foco infeccioso foi abdominal (42,6%) e o Sequential Organ Failure Assessment (SOFA) 13,6±2,7. A prevalência de hipotensão, coagulação de sistema, hipofosfatemia e hipocalemia foi de 82,6, 25,3, 20 e 10,6%, respectivamente. O G1 foi composto de 38 pacientes tratados por 100 sessões, enquanto o G2 foi composto de 37 pacientes tratados por 95 sessões. Ao se comparar as características clínicas e laboratoriais, os grupos apresentaram-se semelhantes quanto à predominância do sexo ... / Extended daily dialysis (EDD) has emerged as an alternative to CRRT in the management of hemodynamically unstable AKI patients, mainly in developed countries. This trial aimed to evaluate and compare the dialytics complications occurred during different durations of EDD sessions (6 vs.10h) in critically ill AKI patients. We included patients older than 18 years with AKI associated with sepsis admitted to the intensive care unit in use of norepinephrine dose ranged from 0.3 to 0.7 ucg/kg/min. Patients were divided into two groups randomly, group 1 (G1) was performed to sessions of 6 h and group 2 (G2) of 10h. Seventy - five patients were treated with 195 sessions EDD for 18 consecutive months. Age was 61.8 ± 15.1 years, predominantly male (70.6 %), the main focus of infection was abdominal (42.6 %) and SOFA was 13.6 ± 2.7. The prevalence of hypotension, filter clotting, hypokalemia, and hypophosphatemia was 82.6, 25.3, 20 and 10.6%, respectively. The G1 was composed of 38 patients treated with 100 sessions, whereas G2 consisted of 37 patients treated with 95 sessions. The two groups were similar in male predominance (65.7 vs. 75.6%, p = 0.34), age (63.614 vs. 59.915.5, p=0.28), and SOFA (13.12.4 vs. 14.23.0, p=0.2). There was no significant difference between the two groups in the prevalence of hypotension, filter clotting (81.5 vs. 83.7%, p=0.8 e 23.6 vs. 27%, p=0.73; respectively), hypokalemia and hypophosphatemia (13.1 vs. 8.1%, p=0.71 and 18.4 vs. 21.6%, p=0.72; respectively). However, the ...

xiv, 233 p. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / In general, postexercise hypotension is characterized by a sustained increase in systemic vascular conductance that is not completely offset by ongoing increases in cardiac output. These hemodynamic changes are present immediately after a single bout of moderate-intensity dynamic exercise in healthy (sedentary and endurance exercise-trained) and hypertensive humans. The mechanisms underlying this postexercise hypotension are currently under investigation; however, the overall hemodynamic response may be altered in response to different factors related to sex, training status, and fluid regulation. The purpose of this dissertation was to investigate the contribution of endogenous hormones associated with the normal menstrual cycle and training status and sex on postexercise hemodynamics and to better understand how fluid replacement and heat-stress affect postexercise hemodynamics in a group of highly trained men. In Chapter IV, the contribution of the menstrual cycle and sex to postexercise hemodynamics was investigated. The results showed that postexercise hemodynamics are largely unaffected by sex and factors associated with the menstrual cycle. In Chapter V, the role of heat-stress and fluid replacement on the postexercise cardiac hemodynamics in a group of endurance exercise-trained men was investigated. These data suggest that fluid replacement and heat-stress mitigate the previously observed fall in cardiac output during exercise recovery in trained men. In Chapter VI, the study investigated the hemodynamic profile in well-hydrated sedentary and trained men and women during recovery from exercise. In contrast to previous research, the results showed a lack of variation in the postexercise hemodynamic response across categories of subjects as there was no evidence of a sex and training interaction. Thus, it appears that factors such as heat-stress and fluid replacement can alter postexercise hemodynamics in trained men; however, factors such as menstrual cycle, sex, and training status do not seem to influence the hemodynamic recovery profile. Yet substantial variation in the postexercise response across individuals remains unexplained. This dissertation contains my previously published and my co-authored material. / Adviser: John R. Halliwill

Background: Two of the excipients in intravenous formulations of amiodarone, polysorbate 80 and benzyl alcohol, have been shown to cause hypotension. A newer formulation of amiodarone, which contains cyclodextrin, is devoid of these excipients. Objective: To evaluate the change in mean arterial pressure when utilizing 2 intravenous amiodarone formulations. Methods: This was a retrospective cohort analysis conducted at an academic medical center. Patients received intravenous amiodarone containing either polysorbate 80/benzyl alcohol (control) or cyclodextrin (cyclodextrin). Patients received these formulations based on a standard institutional protocol of 1 mg/min for 6 hours, followed by 0.5 mg/min for at least 18 hours or until discontinued by the provider. All data were collected from the medical record and included changes in blood pressures, time to lowest systolic blood pressure, concurrent antihypertensive use, and number of patients requiring treatment for hypotension. Results: A total of 160 patients (120 control, 40 cyclodextrin) were included. There was a statistically significant difference in mean arterial pressure between the groups receiving the control formulation of amiodarone compared with the cyclodextrin formulation across the 24-hour maintenance phase infusion (P < 0.001). There was a significant difference between formulations with regard to the change in mean arterial pressure during the 0- to 6-hour and 12- to 18-hour time blocks. There was a statistically significant difference in the number of patients receiving fluid boluses for treatment of hypotension (P = 0.001). Conclusions: The excipients in the formulation of intravenous amiodarone may have a significant role in the hypotensive effects seen throughout the duration the maintenance phase infusion.

Described for the first time approximately 30 years ago, exercise-induced anaphylaxis is a rare disorder characterized by development of a severe allergic response occurring after mild-to-strenuous physical activity. This disorder is especially important to recognize with the recent increase in physical activity and health fitness fads. A number of predisposing factors (eg, prior ingestion of particular food groups) linked to exercise-induced anaphylaxis has been outlined over the years. Mechanisms govern big the condition are still being unveiled, and it is likely that one mechanism involves mast cell degranulation and inflammatory mediator generation resulting from the biochemical effects of exercise, sometimes in the presence of an ingested allergen such that wheat or shell fish. Clinical manifestations usually occur after around 10 minutes of exercise, and follow a specific sequence, starting with pruritis and widespread urticarial lesions, evolving into a more typical anaphylactic picture with respiratory distress and vascular collapse. Fatality is exceedingly rare, with only one documented casein the literature. There is an overlap of symptoms with other syndromes (such as systemic mastocytosis and cholinergic urticaria), and these should be remembered when establishing a differential. Treatment of exercise-induced anaphylaxis consists of immediate stabilization geared toward the anaphylactic response with epinephrine and antihistamines. The patient needs to be educated on preventive measures and equipped with an epinephrine autoinjector in the event of an emergency. Exercise-induced anaphylaxis remains a potentially serious disorder, and the health care provider should be aware of its clinical features and effective management strategies.

No description available.

Thesis (M Sport Sc (Sport Science))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: It is well-known that acute and chronic aerobic and resistance exercise results in decreased blood pressure (BP) in hypertensive individuals. There is little evidence that water exercise has a similar effect on BP response. There is also no certainty regarding the magnitude and duration of post exercise hypotension (PEH) after either land or water-based exercise. Most studies were also performed under controlled laboratory conditions and very few characterised the PEH response under real life conditions. The current study endeavoured to examine the magnitude and duration of PEH after an acute session of water- and land-based exercise during free living conditions in persons with mild to moderate hypertension. Twenty-one men and women (aged 52 ± 10 years) volunteered for the study. All participants were pre-hypertensive or hypertensive. Participants completed a no exercise control session, a water exercise session and a combined aerobic and resistance land exercise session in random order. After all three sessions, participants underwent 24 hour monitoring using an Ergoscan ambulatory BP monitoring device. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and heart rate (HR) were monitored to determine changes from resting values after each session and to compare the PEH responses between land and water exercise. Overall, the land exercise treatment caused a 3.6 mmHg lower average SBP over 24 hours than the control treatment (P = 0.04). The average difference over 24 hours between the water and control treatments was 2.2 mmHg and between land and water exercise it was 1.5 mmHg (P > 0.05). During daytime, both land and water exercise resulted in significantly lower SBP (12.7 and 11.3 mmHg) compared to the control session (2.3 mmHg). The PEH response lasted for 24 hours after land exercise and nine hours after water exercise. There was no difference in the daytime DBP for the three treatments (P > 0.05). Although all three groups showed significant reductions during night time, both exercise treatments showed greater nocturnal falls in SBP, DBP and MAP than the control treatment. / AFRIKAANSE OPSOMMING: Dit is alombekend dat akute en chroniese aërobiese- en weerstandsoefening tot ‘n afname in bloeddruk (BD) lei in persone met hipertensie. Daar is egter min getuienis dat wateroefening dieselfde effek op die bloeddruk respons het. Daar is ook nie sekerheid oor die grootte en duur van post-oefening hipotensie na water- of landoefening nie. Die meeste studies is onder gekontrolleerde laboratorium omstandighede gedoen en min resultate is beskikbaar onder alledaagse lewensomstandighede. Die huidige studie het gepoog om die grootte en duur van die post-oefening hipotensie respons in persone met ligte tot matige hipertensie onder alledaagse omstandighede na ‘n akute sessie van water- en landgebaseerde oefening te ondersoek. Een-en-twintig mans en vrouens (ouderdom 52 ± 10 jaar) het ingewillig om aan die studie deel te neem. Alle deelnemers was hipertensief of pre-hipertensief. Alle deelnemers het ‘n kontrolesessie, ‘n wateroefeningsessie en ‘n gekombineerde aërobiese en weerstands landoefensessie, in lukrake volgorde, voltooi. Na elke sessie het die deelnemers 24 uur bloeddrukmonitering met ‘n Ergoscan wandelende bloeddruk monitor ondergaan. Sistoliese bloeddruk (SBD), diastoliese bloeddruk (DBD), gemiddelde arteriële bloeddruk en harttempo (HT) is gemonitor om die veranderinge vanaf rustende waardes na elke sessie te bepaal en om die hipotensiewe respons na land- en wateroefening te vergelyk. Landoefening het ‘n 3.6 mmHg laer gemiddelde SBD oor 24 uur tot gevolg gehad in vergelyking met die kontrolesessie (P = 0.04). Die gemiddelde verskil oor 24 uur tussen die water- en kontrolesessies was 2.2 mmHg en 1.5 mmHg tussen die land en water oefensessies (P > 0.05). Gedurende die dag het beide die land- and wateroefening gelei tot beduidende laer SBD (12.7 en 11.3 mmHg) in vergelyking met die kontrolesessie (2.3 mmHg). Die post-oefening hipotensie het 24 uur geduur na die landoefening en nege uur na die wateroefening. Daar was geen verskil in DBD gedurende die dag tussen die drie groepe nie (P > 0.05).

Background: Intradialytic hypotension is a potential complication experienced by patients with end-stage renal disease who receive hemodialysis. This complication occurs during the dialysis treatment in 15-30% of all treatments. The multiple comorbidities that exist in hemodialysis patients predispose them to recurrent intradialytic hypotension episodes. Recurrent intradialytic hypotensive episodes can result in negative short-term and long-term clinical consequences. Short-term consequences include complications such as ischemic events (e.g., heart attacks, strokes), clotting of patient dialysis access, or heart rhythm abnormalities. Long-term consequences include end-organ damage, increased cardiovascular morbidity, and a higher mortality rate. Problem Statement: Available nursing interventions used to treat intradialytic hypotension such as decreased dialysis fluid temperature, changes in the calcium and sodium concentrations in the dialysis fluid and oral medication have limited success. Another existing technological intervention called blood volume monitoring shows greater potential success but is currently underutilized. Purpose: The purpose of this literature review is to synthesize current literature on blood volume monitoring technology used to prevent intradialytic hypotension in hemodialysis patients. Methods: A literature review was conducted analyzing pertinent research articles published in the last ten years, in addition to seminal articles. Seventeen articles were retrieved and analyzed that met criteria. Results: Fourteen of the seventeen research studies reached a consensus on the successful use of blood volume monitoring to decrease intradialytic hypotension and the related symptoms. Conclusion: Results of the literature review support the use of blood volume monitoring technology as an effective nursing intervention to prevent intradialytic hypotension in hemodialysis patients.

published_or_final_version / abstract / Medicine / Master / Doctor of Medicine