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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Skarpskytten i Mekaniserad Bataljon 09 : En prövning av definition och utrustningsalternativ / Designated marksman in the mechanized battalion 09 : An examination of definition and equipment

Hansson, Andreas January 2009 (has links)
<p>Inom ramen för den mekaniserade bataljonens organisation har ett flertal plutoner blivit tilldelade PSG90 som skarpskyttebeväpning. Frågan är om denna beväpning skapar effekt för förbandet? Syftet med denna uppsats är att undersöka skarpskyttens roll och beväpningsalternativ inom ramen för den mekaniserade bataljonen.</p><p>Uppsatsen avsåg att genom en hypotesprovning undersöka om tilldelningen av PSG90 till ett flertal plutoner i den mekaniserade bataljonen skapar ökad effekt för förbandet. Undersökningen krävde en delad frågeställning där först själv begreppet skarpskytt behövde definieras. Därefter krävdes en undersökning av denna definition jämtemot empiri för att etablera eftersökta effekter med skarpskytten. Slutligen genomfördes en komparation mellan olika vapensystem, som finns tillgängliga i den svenska arsenalen, och hur dessa förhåller sig till de eftersökta effekterna.</p><p>Uppsatsens resultat kan sammanfattas på följande sätt: Den svenska definitionen av skarpskytt är i sin nuvarande form minimalistisk i jämförelse med andra länders definiton. Skarpskytten måste i den mekaniserade bataljonen lösa många olika former av strid där olika beväpningsalternativ innebär olika för och nackdelar. Tillförandet av PSG90 som skarpskyttebeväpning är inte tillräckligt i förhållande till eftersökta effekter, varpå antingen en prioritering av uppgifter måste göras alternativt en dubbelbeväpning av skarpskytten blir nödvändig.</p> / <p>In the organizational schematic of the mechanized battalion, several platoons have been issued PSG90 sniper rifles as Designated Marksman armament. This raises the question if this armament creates any increased effects for the unit? The purpose of this essay is to examine the role and choice of armament for the Designated Marksman within the mechanized battalion.</p><p>The essay tests the hypothesis that assigning PSG90 sniper rifles to various platoons within the battalion leads to increased effects of the unit. This examination uses several methods of examining this hypothesis. Initially the Swedish definition of Designated Marksman is examined in relations to other countries definitions. Secondly the desired effects are defined from the empiric materiel. Finally a comparison between options of armament available with the Swedish arsenal is made and related to the desired effects.</p><p>The result of the essay can be summarized in the following ways: The Swedish definition of Designated Marksman is in its current form minimalistic in relation to other countries definitions. The Designated Marksman must be able to handle a number of different combat situations where different weapons alternatives offer different pros and cons. The issuing of PSG90 sniper rifles as armament for the designated marksman is insufficient in relations to the desired effects. This results in a situation where tasks either have to be prioritized in relation to the equipment or where the Designated Marksman has to be issued to different weapons, depending on different combat situations.</p>
22

Åskkäpp, bössa och dunderpåk : Automatkarbinen i den svenska försvarsmakten / Thundercane, gun and thunderstick : The assault rifle in the Swedish Armed Forces

Lundin, Sven January 2010 (has links)
<p>Under 1990-talet märktes en tydlig förändring bland automatkarbinerna. De blev mer och mer anpassningsbara och fler tillbehör blev tillgängliga för soldaterna. Samtidigt blev automatkarbiner mer kompakta för att bli mer lämpliga för operationer i urbaniserad terräng och fordonstjänst. Med invasionen av Afghanistan och den därefter följande upprorsbekämpningen upplever många försvarsmakter problem, eftersom striderna sker på antingen väldigt korta eller väldigt långa avstånd. Den ena situationen kräver ett kompakt vapen för SIB medan den andra situationen kräver ett vapen med lång pipa för att kunna uppnå verkan mot en fiende som ofta anfaller från avstånd på 500 meter eller mer. Försvarsmakten hade just startat försök med en uppdaterad version av AK5 när de förband sig att bidra med en reguljär styrka till ISAF. Författaren är av åsikten att Försvarsmakten saknar ett vapensystem på grupp och plutonsnivå för att uppnå verkan på avstånd större än 400 meter som ofta är fallet. Denna uppsats syftar därför till att undersöka hur nästa svenska automatkarbin kan komma att se ut utifrån erfarenheter dragna ifrån Operation Enduring Freedom.</p> / <p>During the 1990ies there is notable change in the assault rifle. They start to get more and more adaptable with a lot more accessories being available to the user. At the same time the assault rifle moves from rifle to carbine as many models become shorter to better suit operations in urban terrainas well as riding in vehicles. With the invasion and the following counter-insurgency operation in Afghanistan a lot of armies are experiencing problems since combat takes places at either very short or long ranges. One calls for acompact carbine suited for close quarters battle and one for a long barrelled rifle which enables soldiers to engage the enemy who often attacks from ranges exceeding the 500 meter mark. The Swedish Armed Forces had just started testing a new updated version of their AK5 assault rifle called AK5C when they committed to contributing a regular force to ISAF. The Author is of the opinion that Swedish forces lack a weapon system on squad and platoon level to engage an enemy atgreater distance than 400m which is often the case. This paper seeks to take a look at what the next Swedish assault rifle could look like taking in mind the experiences from Operation Enduring Freedom.</p>
23

Åskkäpp, bössa och dunderpåk : Automatkarbinen i den svenska försvarsmakten / Thundercane, gun and thunderstick : The assault rifle in the Swedish Armed Forces

Lundin, Sven January 2010 (has links)
Under 1990-talet märktes en tydlig förändring bland automatkarbinerna. De blev mer och mer anpassningsbara och fler tillbehör blev tillgängliga för soldaterna. Samtidigt blev automatkarbiner mer kompakta för att bli mer lämpliga för operationer i urbaniserad terräng och fordonstjänst. Med invasionen av Afghanistan och den därefter följande upprorsbekämpningen upplever många försvarsmakter problem, eftersom striderna sker på antingen väldigt korta eller väldigt långa avstånd. Den ena situationen kräver ett kompakt vapen för SIB medan den andra situationen kräver ett vapen med lång pipa för att kunna uppnå verkan mot en fiende som ofta anfaller från avstånd på 500 meter eller mer. Försvarsmakten hade just startat försök med en uppdaterad version av AK5 när de förband sig att bidra med en reguljär styrka till ISAF. Författaren är av åsikten att Försvarsmakten saknar ett vapensystem på grupp och plutonsnivå för att uppnå verkan på avstånd större än 400 meter som ofta är fallet. Denna uppsats syftar därför till att undersöka hur nästa svenska automatkarbin kan komma att se ut utifrån erfarenheter dragna ifrån Operation Enduring Freedom. / During the 1990ies there is notable change in the assault rifle. They start to get more and more adaptable with a lot more accessories being available to the user. At the same time the assault rifle moves from rifle to carbine as many models become shorter to better suit operations in urban terrainas well as riding in vehicles. With the invasion and the following counter-insurgency operation in Afghanistan a lot of armies are experiencing problems since combat takes places at either very short or long ranges. One calls for acompact carbine suited for close quarters battle and one for a long barrelled rifle which enables soldiers to engage the enemy who often attacks from ranges exceeding the 500 meter mark. The Swedish Armed Forces had just started testing a new updated version of their AK5 assault rifle called AK5C when they committed to contributing a regular force to ISAF. The Author is of the opinion that Swedish forces lack a weapon system on squad and platoon level to engage an enemy atgreater distance than 400m which is often the case. This paper seeks to take a look at what the next Swedish assault rifle could look like taking in mind the experiences from Operation Enduring Freedom.
24

Skarpskytten i Mekaniserad Bataljon 09 : En prövning av definition och utrustningsalternativ / Designated marksman in the mechanized battalion 09 : An examination of definition and equipment

Hansson, Andreas January 2009 (has links)
Inom ramen för den mekaniserade bataljonens organisation har ett flertal plutoner blivit tilldelade PSG90 som skarpskyttebeväpning. Frågan är om denna beväpning skapar effekt för förbandet? Syftet med denna uppsats är att undersöka skarpskyttens roll och beväpningsalternativ inom ramen för den mekaniserade bataljonen. Uppsatsen avsåg att genom en hypotesprovning undersöka om tilldelningen av PSG90 till ett flertal plutoner i den mekaniserade bataljonen skapar ökad effekt för förbandet. Undersökningen krävde en delad frågeställning där först själv begreppet skarpskytt behövde definieras. Därefter krävdes en undersökning av denna definition jämtemot empiri för att etablera eftersökta effekter med skarpskytten. Slutligen genomfördes en komparation mellan olika vapensystem, som finns tillgängliga i den svenska arsenalen, och hur dessa förhåller sig till de eftersökta effekterna. Uppsatsens resultat kan sammanfattas på följande sätt: Den svenska definitionen av skarpskytt är i sin nuvarande form minimalistisk i jämförelse med andra länders definiton. Skarpskytten måste i den mekaniserade bataljonen lösa många olika former av strid där olika beväpningsalternativ innebär olika för och nackdelar. Tillförandet av PSG90 som skarpskyttebeväpning är inte tillräckligt i förhållande till eftersökta effekter, varpå antingen en prioritering av uppgifter måste göras alternativt en dubbelbeväpning av skarpskytten blir nödvändig. / In the organizational schematic of the mechanized battalion, several platoons have been issued PSG90 sniper rifles as Designated Marksman armament. This raises the question if this armament creates any increased effects for the unit? The purpose of this essay is to examine the role and choice of armament for the Designated Marksman within the mechanized battalion. The essay tests the hypothesis that assigning PSG90 sniper rifles to various platoons within the battalion leads to increased effects of the unit. This examination uses several methods of examining this hypothesis. Initially the Swedish definition of Designated Marksman is examined in relations to other countries definitions. Secondly the desired effects are defined from the empiric materiel. Finally a comparison between options of armament available with the Swedish arsenal is made and related to the desired effects. The result of the essay can be summarized in the following ways: The Swedish definition of Designated Marksman is in its current form minimalistic in relation to other countries definitions. The Designated Marksman must be able to handle a number of different combat situations where different weapons alternatives offer different pros and cons. The issuing of PSG90 sniper rifles as armament for the designated marksman is insufficient in relations to the desired effects. This results in a situation where tasks either have to be prioritized in relation to the equipment or where the Designated Marksman has to be issued to different weapons, depending on different combat situations.
25

EFFECTS OF AUGMENTED REAL-TIME AUDITORY FEEDBACK ON TOP-LEVEL PRECISION SHOOTING PERFORMANCE

Underwood, Stacy Marie 01 January 2009 (has links)
This study examined the effects of training with real-time auditory feedback in precision shooting. Top-level shooters (N=9) were randomly assigned to the feedback or nonfeedback group. Each group performed a pre-test, a 4-week training intervention and a post-test. The feedback group was provided with augmented real-time auditory feedback based on postural and rifle barrel stability during training sessions. Increases in performance were measured through changes in postural stability, rifle barrel stability, shot outcome and shot group diameter. Real-time auditory feedback did not increase postural or rifle barrel stability in the feedback group. No meaningful differences were found related to shot outcome or shot group diameter in air rifle testing. The feedback group was able to reduce shot group diameter during smallbore testing. In summary, the augmented real-time auditory feedback did not improve postural or rifle barrel stability. Future research should focus on examining the effects of auditory feedback on smallbore performance.
26

The National Rifle Association In Context: Gun Rights in Relation to the National Security State

Young, Catherine L 01 January 2014 (has links)
The National Rifle Association (NRA) has dominated the debate over gun rights since the late 1960s. In many ways, its political power is unassailable. However, a historical analysis of the NRA's deeply rooted connection to the operations of the American government proves this has not always been so. This thesis is an examination of the mission and actions of the NRA through the lens of the government's expansion of power during and beyond the Cold War.
27

Nefrotoxicidade de polimixinas : fatores de risco e comparação entre polimixina B e colistina

Rigatto, Maria Helena da Silva Pitombeira January 2015 (has links)
Base teórica: As polimixinas, polimixina B e polimixina E (também denominada colistina), são antibióticos usados como opção de última linha no tratamento de infecções por bacilos Gram negativos multirresistentes. Apesar de serem drogas antigas, suas propriedades nefrotóxicas ainda são pobremente entendidas. Toxicidade direta aos túbulos renais proximais levando à necrose tubular e dano oxidativo estão envolvidos no mecanismo fisiopatológico da nefrotoxicidade por esta classe de drogas. Uso de maior dose total foi implicada em maior nefrotoxicidade, no entanto a relação entre dose recebida e peso do paciente, controlado para outras variáveis confundidoras ainda precisa ser clarificada. Além disso, diferenças farmacocinéticas entre polimixina B e a colistina impedem o extrapolamento de dados entre estas drogas, sendo importante a avaliação de desfecho clínico e nefrotoxicidade de cada uma e a comparação entre elas. Objetivo: Avaliar comparativamente a nefrotoxicidade (através de critério de RIFLE) e mortalidade em 30 dias em pacientes tratados com polimixina B e colistina. Métodos: Estudo de coorte prospectivo, multicêntrico com coleta consecutiva de dados. Critérios de inclusão: pacientes ≥ 18 anos em uso de polimixina B ou colistina. Critérios de exclusão: uso de polimixina B por período ≤48 horas, segundo uso de polimixina B, diálise no início do tratamento ou DCE ≤ 10ml/min nos pacientes avaliados para nefrotoxicidade. Fatores potencialmente relacionados à nefrotoxicidade ou a mortalidade em 30 dias como: variáveis demográficas (idade, sexo), variáveis individuais (peso, comorbidades, escore de Charlson), fatores de gravidade (escore APACHE, internação em UTI, ventilação mecânica, uso de vasopressor), fatores relacionados à nefrotoxicidade (outras drogas nefrotóxicas e uso de contraste endovenoso), dose de polimixina utilizada (total, média diária e em mg/kg/dia), associação de drogas e características da infecção ( sítio e isolado microbiológico) foram avaliadas em análise bivariada. Variáveis com P≤0.2 foram incluídas uma a uma, em ordem crescente, em modelo de regressão de COX. Variáveis com P< 0.1 permaneceram no modelo final. Resultados: Quatrocentos e dez pacientes foram incluídos na coorte de polimixina B. Nefrotoxicidade ocorreu em 189 (46.1%) pacientes. Dose de polimixina B ≥150mg/dia foi fator de risco independente para nefrotoxicidade: adjusted Hazard Ratio (HR) 1.95, IC 95% 1.31-2.89, P=0,01. Peso e idade também foram associados de forma independente com nefrotoxicidade. A probabilidade de desenvolver nefrotoxicidade aumentou significativamente com doses entre 150-199mg/dia, independente do peso do pacientes, sem aumento significativo com doses maiores. Nefrotoxidade foi relacionada à maior mortalidade em 30 dias, embora não tenha atingido significância estatística (aHR 1,35, IC 95% 0,99-1,85, P=0,06), enquanto dose ≥150mg/dia não aumentou o risco de mortalidade apesar de sua associação com nefrotoxicidade. Na avaliação de mortalidade foram avaliados apenas pacientes internados em UTI e com infecção microbiologicamente confirmada. Cento e nove pacientes foram incluídos: 47 (43.1%) tratados com polimixina B combinada com outro antibiótico e 62 (56.8%) com polimixina B em monoterapia. A mortalidade geral em 30 dias foi 56.9% (62 pacientes): 32,3% (20 de 47) e 67,7% (42 de 62), P=0,02, nos grupos de terapia combinada e monoterapia, respectivamente. Terapia combinada foi associada de forma independente à menor mortalidade em 30 dias (HR, 0,38; IC 95% 0,21-0,68; P=0,001). Maior escore APACHE foi fator de risco independente para mortalidade em 30 dias. Oitenta e um pacientes foram incluídos na coorte de colistina e foram pareados com 162 pacientes do grupo de polymyxin B, de acordo com a DCE (±25ml/min). A incidência falência renal foi de 23,5%: 38.3% no grupo da colistina e 16.1% no grupo da polimixina B, P<0,001 e ocorreu independente da DCE de base. Na análise multivariada, terapia com colistina foi fator de risco independente para falência renal (HR, 2,96, IC95%, 1,68- 5,22, P<0,001), assim como internação em UTI, maior peso e idade . Pacientes que desenvolveram falência renal morreram mais (50,9%, 29/57) do que os que não a desenvolveram (29.0%, 54/186), P=0,004; mas a mortalidade em 30 dias não diferiu entre os grupos: 30.9% e 35.8%, P=0,53, nos pacientes em uso de colistina e polimixina B, respectivamente. Conclusão: A dose média diária de polimixina B é diretamente relacionada ao risco de nefrotoxicidade, independente do peso do paciente. Mortalidade em 30 dias tendeu a ser maior em quem desenvolveu nefrotoxicidade. O uso de terapia combinada com polimixina B mostrou ser protetor para mortalidade em 30 dias. Colistina mostrou estar associada ao maior desenvolvimento de falência renal quando comparada à polimixina B. / Background: Polymyxins, polymyxin B and polymyxin E (also called colistin), are last line resort therapies to treat multi-resistant Gram negative bacteria. Despite the fact that they are old antibiotics, their nephrotoxicity properties are still poorly understood. Direct proximal renal tubular toxicity leading to tubular necrosis and oxidative damage are involved in the physiopathologic mechanism of injury by these drugs. Higher doses were implicated in nephrotoxicity, however the relation between dose and weight, controlled for confounding variables, still need to be clarified. Moreover, pharmacokinetic diferences between polymyxin B and colistin avoid direct extrapolation of data between these drugs. It is then important to evaluate clinical outcomes and nephrotoxicity of each of these drugs and to compare its results. Objective: To compare nephrotoxicity (using RIFLE score) and 30-day mortality in patients treated with colistin and polymyxin B. Methods: We performed a multicenter prospective cohort study with consecutive data collection. Inclusion criteria: patients ≥ 18 years old receiving polymyxin B or colistin. Exclusion criteria: polymyxin use for ≤48 hours, having received polymyxin before, dyalisis or GFR≤ 10ml/min in the beginning of therapy in patients evaluated for nephrotoxicity. Factors potentially related to nephrotoxicity or 30-day mortality such as: demographic data (age, gender), individual characteristics (weight, comorbidities, Charlson score), disease severity factors (APACHE score, ICU admission, mechanical ventilation, use of vasoactive drugs, nephrotoxicity related factors ( other nephrotoxic drugs and use of nephrotoxic contrast), polymyxin dose (total dose, average daily dose, mg/kg/day dose), combined therapy and infection characteristics (site of infection, microbiologic isolates) were evaluated in bivariate analysis. Variables with P≤0.2 were included one by one, in a COX regression model. Variables with P< 0.1 remained in the final model. Results: Four-hundred and ten patients were included. AKI occurred in 189 (46.1%) patients. Polymyxin B dose ≥150mg/day was a risk factor for AKI: adjusted Hazard Ratio (HR) 1.95, 95% CI 1.31-2.89, P=0.01. Higher weight and age were also independently associated with AKI. The probability of developing AKI significantly increases with doses between 150-199mg/day, regardless the patients’ weight, with no significant increase with higher doses. AKI was barely associated with increased risk for 30-day mortality (adjusted HR 1.35, 95% CI 0.99-1.85, P=0.06), while ≥150mg/day did not increase this risk despite its association with AKI. On mortality evaluation, a total of 109 patients were included: 47 (43.1%) treated with polymyxin B in combination and 62 (56.8%) with polymyxin B in monotherapy. The overall 30-day mortality was 56.9% (62 patients): 32.3% (20 of 47) and 67.7% (42 of 62), p=0.02, in combination and monotherapy groups, respectively. Combination therapy was independently associated with lower 30-day mortality (Hazard Ratio, 0.38; 95%CI 0.21-0.68; p=0.001), along with a higher APACHE score. Eighty one patients in colistin group were matched to 162 in polymyxin B group, according to baseline creatinine clearance (±25ml/min). . The incidence of renal failure was 23.5%: 38.3% in CMS and 16.1% in polymyxin B group, P<0.001, regardless the baseline creatinine clearance of patients. In multivariate analysis, CMS therapy was an independent risk factor for renal failure (Hazard Ration, 2.96, 95%Confidence Interval, 1.68-5.22, P<0.001), along with intensive care unit admission, higher weight and older age. Patients who developed renal failure presented higher 30-mortality rates (50.9%, 29/57 patients) than those who did not present renal failure (29.0%, 54/186), P=0.004; but CMS (30.9%) and polymyxin B (35.8%) treated patients had similar 30-day mortality, P=0.53. Conclusion: Median daily dose of polymyxin B therapy was directly related to the risk of developing nephrotoxicity, regardless of patient’s weight. 30-day mortality was higher in patients who developed nephrotoxicity. Combined therapy with polymyxin B was protective to 30-day mortality. Colistin use was related to higher rates of renal failure when compared to polymyxin B.
28

Nefrotoxicidade de polimixinas : fatores de risco e comparação entre polimixina B e colistina

Rigatto, Maria Helena da Silva Pitombeira January 2015 (has links)
Base teórica: As polimixinas, polimixina B e polimixina E (também denominada colistina), são antibióticos usados como opção de última linha no tratamento de infecções por bacilos Gram negativos multirresistentes. Apesar de serem drogas antigas, suas propriedades nefrotóxicas ainda são pobremente entendidas. Toxicidade direta aos túbulos renais proximais levando à necrose tubular e dano oxidativo estão envolvidos no mecanismo fisiopatológico da nefrotoxicidade por esta classe de drogas. Uso de maior dose total foi implicada em maior nefrotoxicidade, no entanto a relação entre dose recebida e peso do paciente, controlado para outras variáveis confundidoras ainda precisa ser clarificada. Além disso, diferenças farmacocinéticas entre polimixina B e a colistina impedem o extrapolamento de dados entre estas drogas, sendo importante a avaliação de desfecho clínico e nefrotoxicidade de cada uma e a comparação entre elas. Objetivo: Avaliar comparativamente a nefrotoxicidade (através de critério de RIFLE) e mortalidade em 30 dias em pacientes tratados com polimixina B e colistina. Métodos: Estudo de coorte prospectivo, multicêntrico com coleta consecutiva de dados. Critérios de inclusão: pacientes ≥ 18 anos em uso de polimixina B ou colistina. Critérios de exclusão: uso de polimixina B por período ≤48 horas, segundo uso de polimixina B, diálise no início do tratamento ou DCE ≤ 10ml/min nos pacientes avaliados para nefrotoxicidade. Fatores potencialmente relacionados à nefrotoxicidade ou a mortalidade em 30 dias como: variáveis demográficas (idade, sexo), variáveis individuais (peso, comorbidades, escore de Charlson), fatores de gravidade (escore APACHE, internação em UTI, ventilação mecânica, uso de vasopressor), fatores relacionados à nefrotoxicidade (outras drogas nefrotóxicas e uso de contraste endovenoso), dose de polimixina utilizada (total, média diária e em mg/kg/dia), associação de drogas e características da infecção ( sítio e isolado microbiológico) foram avaliadas em análise bivariada. Variáveis com P≤0.2 foram incluídas uma a uma, em ordem crescente, em modelo de regressão de COX. Variáveis com P< 0.1 permaneceram no modelo final. Resultados: Quatrocentos e dez pacientes foram incluídos na coorte de polimixina B. Nefrotoxicidade ocorreu em 189 (46.1%) pacientes. Dose de polimixina B ≥150mg/dia foi fator de risco independente para nefrotoxicidade: adjusted Hazard Ratio (HR) 1.95, IC 95% 1.31-2.89, P=0,01. Peso e idade também foram associados de forma independente com nefrotoxicidade. A probabilidade de desenvolver nefrotoxicidade aumentou significativamente com doses entre 150-199mg/dia, independente do peso do pacientes, sem aumento significativo com doses maiores. Nefrotoxidade foi relacionada à maior mortalidade em 30 dias, embora não tenha atingido significância estatística (aHR 1,35, IC 95% 0,99-1,85, P=0,06), enquanto dose ≥150mg/dia não aumentou o risco de mortalidade apesar de sua associação com nefrotoxicidade. Na avaliação de mortalidade foram avaliados apenas pacientes internados em UTI e com infecção microbiologicamente confirmada. Cento e nove pacientes foram incluídos: 47 (43.1%) tratados com polimixina B combinada com outro antibiótico e 62 (56.8%) com polimixina B em monoterapia. A mortalidade geral em 30 dias foi 56.9% (62 pacientes): 32,3% (20 de 47) e 67,7% (42 de 62), P=0,02, nos grupos de terapia combinada e monoterapia, respectivamente. Terapia combinada foi associada de forma independente à menor mortalidade em 30 dias (HR, 0,38; IC 95% 0,21-0,68; P=0,001). Maior escore APACHE foi fator de risco independente para mortalidade em 30 dias. Oitenta e um pacientes foram incluídos na coorte de colistina e foram pareados com 162 pacientes do grupo de polymyxin B, de acordo com a DCE (±25ml/min). A incidência falência renal foi de 23,5%: 38.3% no grupo da colistina e 16.1% no grupo da polimixina B, P<0,001 e ocorreu independente da DCE de base. Na análise multivariada, terapia com colistina foi fator de risco independente para falência renal (HR, 2,96, IC95%, 1,68- 5,22, P<0,001), assim como internação em UTI, maior peso e idade . Pacientes que desenvolveram falência renal morreram mais (50,9%, 29/57) do que os que não a desenvolveram (29.0%, 54/186), P=0,004; mas a mortalidade em 30 dias não diferiu entre os grupos: 30.9% e 35.8%, P=0,53, nos pacientes em uso de colistina e polimixina B, respectivamente. Conclusão: A dose média diária de polimixina B é diretamente relacionada ao risco de nefrotoxicidade, independente do peso do paciente. Mortalidade em 30 dias tendeu a ser maior em quem desenvolveu nefrotoxicidade. O uso de terapia combinada com polimixina B mostrou ser protetor para mortalidade em 30 dias. Colistina mostrou estar associada ao maior desenvolvimento de falência renal quando comparada à polimixina B. / Background: Polymyxins, polymyxin B and polymyxin E (also called colistin), are last line resort therapies to treat multi-resistant Gram negative bacteria. Despite the fact that they are old antibiotics, their nephrotoxicity properties are still poorly understood. Direct proximal renal tubular toxicity leading to tubular necrosis and oxidative damage are involved in the physiopathologic mechanism of injury by these drugs. Higher doses were implicated in nephrotoxicity, however the relation between dose and weight, controlled for confounding variables, still need to be clarified. Moreover, pharmacokinetic diferences between polymyxin B and colistin avoid direct extrapolation of data between these drugs. It is then important to evaluate clinical outcomes and nephrotoxicity of each of these drugs and to compare its results. Objective: To compare nephrotoxicity (using RIFLE score) and 30-day mortality in patients treated with colistin and polymyxin B. Methods: We performed a multicenter prospective cohort study with consecutive data collection. Inclusion criteria: patients ≥ 18 years old receiving polymyxin B or colistin. Exclusion criteria: polymyxin use for ≤48 hours, having received polymyxin before, dyalisis or GFR≤ 10ml/min in the beginning of therapy in patients evaluated for nephrotoxicity. Factors potentially related to nephrotoxicity or 30-day mortality such as: demographic data (age, gender), individual characteristics (weight, comorbidities, Charlson score), disease severity factors (APACHE score, ICU admission, mechanical ventilation, use of vasoactive drugs, nephrotoxicity related factors ( other nephrotoxic drugs and use of nephrotoxic contrast), polymyxin dose (total dose, average daily dose, mg/kg/day dose), combined therapy and infection characteristics (site of infection, microbiologic isolates) were evaluated in bivariate analysis. Variables with P≤0.2 were included one by one, in a COX regression model. Variables with P< 0.1 remained in the final model. Results: Four-hundred and ten patients were included. AKI occurred in 189 (46.1%) patients. Polymyxin B dose ≥150mg/day was a risk factor for AKI: adjusted Hazard Ratio (HR) 1.95, 95% CI 1.31-2.89, P=0.01. Higher weight and age were also independently associated with AKI. The probability of developing AKI significantly increases with doses between 150-199mg/day, regardless the patients’ weight, with no significant increase with higher doses. AKI was barely associated with increased risk for 30-day mortality (adjusted HR 1.35, 95% CI 0.99-1.85, P=0.06), while ≥150mg/day did not increase this risk despite its association with AKI. On mortality evaluation, a total of 109 patients were included: 47 (43.1%) treated with polymyxin B in combination and 62 (56.8%) with polymyxin B in monotherapy. The overall 30-day mortality was 56.9% (62 patients): 32.3% (20 of 47) and 67.7% (42 of 62), p=0.02, in combination and monotherapy groups, respectively. Combination therapy was independently associated with lower 30-day mortality (Hazard Ratio, 0.38; 95%CI 0.21-0.68; p=0.001), along with a higher APACHE score. Eighty one patients in colistin group were matched to 162 in polymyxin B group, according to baseline creatinine clearance (±25ml/min). . The incidence of renal failure was 23.5%: 38.3% in CMS and 16.1% in polymyxin B group, P<0.001, regardless the baseline creatinine clearance of patients. In multivariate analysis, CMS therapy was an independent risk factor for renal failure (Hazard Ration, 2.96, 95%Confidence Interval, 1.68-5.22, P<0.001), along with intensive care unit admission, higher weight and older age. Patients who developed renal failure presented higher 30-mortality rates (50.9%, 29/57 patients) than those who did not present renal failure (29.0%, 54/186), P=0.004; but CMS (30.9%) and polymyxin B (35.8%) treated patients had similar 30-day mortality, P=0.53. Conclusion: Median daily dose of polymyxin B therapy was directly related to the risk of developing nephrotoxicity, regardless of patient’s weight. 30-day mortality was higher in patients who developed nephrotoxicity. Combined therapy with polymyxin B was protective to 30-day mortality. Colistin use was related to higher rates of renal failure when compared to polymyxin B.
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Nefrotoxicidade de polimixinas : fatores de risco e comparação entre polimixina B e colistina

Rigatto, Maria Helena da Silva Pitombeira January 2015 (has links)
Base teórica: As polimixinas, polimixina B e polimixina E (também denominada colistina), são antibióticos usados como opção de última linha no tratamento de infecções por bacilos Gram negativos multirresistentes. Apesar de serem drogas antigas, suas propriedades nefrotóxicas ainda são pobremente entendidas. Toxicidade direta aos túbulos renais proximais levando à necrose tubular e dano oxidativo estão envolvidos no mecanismo fisiopatológico da nefrotoxicidade por esta classe de drogas. Uso de maior dose total foi implicada em maior nefrotoxicidade, no entanto a relação entre dose recebida e peso do paciente, controlado para outras variáveis confundidoras ainda precisa ser clarificada. Além disso, diferenças farmacocinéticas entre polimixina B e a colistina impedem o extrapolamento de dados entre estas drogas, sendo importante a avaliação de desfecho clínico e nefrotoxicidade de cada uma e a comparação entre elas. Objetivo: Avaliar comparativamente a nefrotoxicidade (através de critério de RIFLE) e mortalidade em 30 dias em pacientes tratados com polimixina B e colistina. Métodos: Estudo de coorte prospectivo, multicêntrico com coleta consecutiva de dados. Critérios de inclusão: pacientes ≥ 18 anos em uso de polimixina B ou colistina. Critérios de exclusão: uso de polimixina B por período ≤48 horas, segundo uso de polimixina B, diálise no início do tratamento ou DCE ≤ 10ml/min nos pacientes avaliados para nefrotoxicidade. Fatores potencialmente relacionados à nefrotoxicidade ou a mortalidade em 30 dias como: variáveis demográficas (idade, sexo), variáveis individuais (peso, comorbidades, escore de Charlson), fatores de gravidade (escore APACHE, internação em UTI, ventilação mecânica, uso de vasopressor), fatores relacionados à nefrotoxicidade (outras drogas nefrotóxicas e uso de contraste endovenoso), dose de polimixina utilizada (total, média diária e em mg/kg/dia), associação de drogas e características da infecção ( sítio e isolado microbiológico) foram avaliadas em análise bivariada. Variáveis com P≤0.2 foram incluídas uma a uma, em ordem crescente, em modelo de regressão de COX. Variáveis com P< 0.1 permaneceram no modelo final. Resultados: Quatrocentos e dez pacientes foram incluídos na coorte de polimixina B. Nefrotoxicidade ocorreu em 189 (46.1%) pacientes. Dose de polimixina B ≥150mg/dia foi fator de risco independente para nefrotoxicidade: adjusted Hazard Ratio (HR) 1.95, IC 95% 1.31-2.89, P=0,01. Peso e idade também foram associados de forma independente com nefrotoxicidade. A probabilidade de desenvolver nefrotoxicidade aumentou significativamente com doses entre 150-199mg/dia, independente do peso do pacientes, sem aumento significativo com doses maiores. Nefrotoxidade foi relacionada à maior mortalidade em 30 dias, embora não tenha atingido significância estatística (aHR 1,35, IC 95% 0,99-1,85, P=0,06), enquanto dose ≥150mg/dia não aumentou o risco de mortalidade apesar de sua associação com nefrotoxicidade. Na avaliação de mortalidade foram avaliados apenas pacientes internados em UTI e com infecção microbiologicamente confirmada. Cento e nove pacientes foram incluídos: 47 (43.1%) tratados com polimixina B combinada com outro antibiótico e 62 (56.8%) com polimixina B em monoterapia. A mortalidade geral em 30 dias foi 56.9% (62 pacientes): 32,3% (20 de 47) e 67,7% (42 de 62), P=0,02, nos grupos de terapia combinada e monoterapia, respectivamente. Terapia combinada foi associada de forma independente à menor mortalidade em 30 dias (HR, 0,38; IC 95% 0,21-0,68; P=0,001). Maior escore APACHE foi fator de risco independente para mortalidade em 30 dias. Oitenta e um pacientes foram incluídos na coorte de colistina e foram pareados com 162 pacientes do grupo de polymyxin B, de acordo com a DCE (±25ml/min). A incidência falência renal foi de 23,5%: 38.3% no grupo da colistina e 16.1% no grupo da polimixina B, P<0,001 e ocorreu independente da DCE de base. Na análise multivariada, terapia com colistina foi fator de risco independente para falência renal (HR, 2,96, IC95%, 1,68- 5,22, P<0,001), assim como internação em UTI, maior peso e idade . Pacientes que desenvolveram falência renal morreram mais (50,9%, 29/57) do que os que não a desenvolveram (29.0%, 54/186), P=0,004; mas a mortalidade em 30 dias não diferiu entre os grupos: 30.9% e 35.8%, P=0,53, nos pacientes em uso de colistina e polimixina B, respectivamente. Conclusão: A dose média diária de polimixina B é diretamente relacionada ao risco de nefrotoxicidade, independente do peso do paciente. Mortalidade em 30 dias tendeu a ser maior em quem desenvolveu nefrotoxicidade. O uso de terapia combinada com polimixina B mostrou ser protetor para mortalidade em 30 dias. Colistina mostrou estar associada ao maior desenvolvimento de falência renal quando comparada à polimixina B. / Background: Polymyxins, polymyxin B and polymyxin E (also called colistin), are last line resort therapies to treat multi-resistant Gram negative bacteria. Despite the fact that they are old antibiotics, their nephrotoxicity properties are still poorly understood. Direct proximal renal tubular toxicity leading to tubular necrosis and oxidative damage are involved in the physiopathologic mechanism of injury by these drugs. Higher doses were implicated in nephrotoxicity, however the relation between dose and weight, controlled for confounding variables, still need to be clarified. Moreover, pharmacokinetic diferences between polymyxin B and colistin avoid direct extrapolation of data between these drugs. It is then important to evaluate clinical outcomes and nephrotoxicity of each of these drugs and to compare its results. Objective: To compare nephrotoxicity (using RIFLE score) and 30-day mortality in patients treated with colistin and polymyxin B. Methods: We performed a multicenter prospective cohort study with consecutive data collection. Inclusion criteria: patients ≥ 18 years old receiving polymyxin B or colistin. Exclusion criteria: polymyxin use for ≤48 hours, having received polymyxin before, dyalisis or GFR≤ 10ml/min in the beginning of therapy in patients evaluated for nephrotoxicity. Factors potentially related to nephrotoxicity or 30-day mortality such as: demographic data (age, gender), individual characteristics (weight, comorbidities, Charlson score), disease severity factors (APACHE score, ICU admission, mechanical ventilation, use of vasoactive drugs, nephrotoxicity related factors ( other nephrotoxic drugs and use of nephrotoxic contrast), polymyxin dose (total dose, average daily dose, mg/kg/day dose), combined therapy and infection characteristics (site of infection, microbiologic isolates) were evaluated in bivariate analysis. Variables with P≤0.2 were included one by one, in a COX regression model. Variables with P< 0.1 remained in the final model. Results: Four-hundred and ten patients were included. AKI occurred in 189 (46.1%) patients. Polymyxin B dose ≥150mg/day was a risk factor for AKI: adjusted Hazard Ratio (HR) 1.95, 95% CI 1.31-2.89, P=0.01. Higher weight and age were also independently associated with AKI. The probability of developing AKI significantly increases with doses between 150-199mg/day, regardless the patients’ weight, with no significant increase with higher doses. AKI was barely associated with increased risk for 30-day mortality (adjusted HR 1.35, 95% CI 0.99-1.85, P=0.06), while ≥150mg/day did not increase this risk despite its association with AKI. On mortality evaluation, a total of 109 patients were included: 47 (43.1%) treated with polymyxin B in combination and 62 (56.8%) with polymyxin B in monotherapy. The overall 30-day mortality was 56.9% (62 patients): 32.3% (20 of 47) and 67.7% (42 of 62), p=0.02, in combination and monotherapy groups, respectively. Combination therapy was independently associated with lower 30-day mortality (Hazard Ratio, 0.38; 95%CI 0.21-0.68; p=0.001), along with a higher APACHE score. Eighty one patients in colistin group were matched to 162 in polymyxin B group, according to baseline creatinine clearance (±25ml/min). . The incidence of renal failure was 23.5%: 38.3% in CMS and 16.1% in polymyxin B group, P<0.001, regardless the baseline creatinine clearance of patients. In multivariate analysis, CMS therapy was an independent risk factor for renal failure (Hazard Ration, 2.96, 95%Confidence Interval, 1.68-5.22, P<0.001), along with intensive care unit admission, higher weight and older age. Patients who developed renal failure presented higher 30-mortality rates (50.9%, 29/57 patients) than those who did not present renal failure (29.0%, 54/186), P=0.004; but CMS (30.9%) and polymyxin B (35.8%) treated patients had similar 30-day mortality, P=0.53. Conclusion: Median daily dose of polymyxin B therapy was directly related to the risk of developing nephrotoxicity, regardless of patient’s weight. 30-day mortality was higher in patients who developed nephrotoxicity. Combined therapy with polymyxin B was protective to 30-day mortality. Colistin use was related to higher rates of renal failure when compared to polymyxin B.
30

Visceral leishmaniasis. Kala-azar. Acute kidney injury. Mortality. Risk factors. RIFLE / ManifestaÃÃes clÃnicas e fatores de risco relacionados à lesÃo renal aguda na Leishmaniose visceral e aplicaÃÃo do critÃrio Rifle

Michelle Jacintha Cavalcante Oliveira 10 May 2010 (has links)
Background. There are few studies of renal function evaluation in visceral leishmaniasis (Kala-azar). The aim of this study was to investigate the clinical manifest and the risk factors associated with acute kidney injury (AKI) based on RIFLE criteria in patients with visceral leishmaniasis (VL). Methods. A retrospective study of medical records from patients over 14 years old, without previous kidney disease, with VL, treated at SÃo Josà Infectious Diseases Hospital, from 2002 to 2008. Clinical manifestations and risk factors for AKI (defined by using RIFLE criteria) were studied. A multivariate analysis was performed to analyze the risk factors for AKI. Results. A total of 224 patients were included. The mean age was 36Â15 years and 76.8% were males. AKI was observed in 76 patients (33.9% of cases) and % 52.6 (40) were class F on RIFLE criteria. The main clinical symptoms were dyspnea, edema and jaundice in patients with VL and AKI (p<0.05). Oliguria was observed in 6.5% of patients with AKI. Risk factors associated with AKI were male gender (OR=2.2, 95% CI= 1.0-4.7, p=0.03), age > 40 years (OR = 1.05, 95% CI= 1.02-1.08, p < 0.001) and jaundice (OR=2.9, 95% CI= 1.5-5.8 p=0.002). There was an strong association between amphotericin B use and AKI (OR=18.4, 95% CI=7.9-42.8, p<0.0001), whereas glucantime use was associated with a lower incidence of AKI when compared to amphotericin B users (OR=0.05, 95% CI=0.02-0.12, p<0.0001). Mortality was 13.3% and it was higher in AKI patients (30.2% vs. 4.7%, p<0.0001). RIFLE criteria presented mortality 40%, 20.8% e 35% in R, I and F respective class. Conclusions. The risk factors associated with AKI in patients with VL were male gender, advanced age, jaundice and amphotericin B. The last one was the most important factor of AKI in VL. / IntroduÃÃo. Hà poucos dados na literatura que relacionam a Leishmaniose visceral (LV) à lesÃo renal aguda (LRA). O objetivo deste estudo à avaliar as manifestaÃÃes clÃnicas e fatores de risco associados à LRA em pacientes com LV e aplicar o critÃrio RIFLE. MÃtodo. Estudo retrospectivo, incluindo pacientes acima de 14 anos, sem doenÃa renal prÃvia, com diagnÃstico de LV, internados no HSJ entre 2002 e 2008. Foram avaliadas manifestaÃÃes clÃnicas e os fatores de risco relacionados à LRA (avaliada atravÃs do critÃrio RIFLE) nesses pacientes, aplicando regressÃo logÃstica multivariada. Resultados. Foram incluÃdos 224 pacientes com idade mÃdia de 36Â15 anos sendo 76,8% do gÃnero masculino. LRA foi observada em 76 pacientes (33,9%) sendo que 52,6% (40) estavam na classe F do critÃrio RIFLE. Dispneia, edema e icterÃcia foram os principais sinais e sintomas associados à LRA (p<0,05). OligÃria foi observada em 6,5% dos pacientes com LRA. Os fatores de risco associados à LRA foram gÃnero masculino (OR=2,2, 95% IC=1,0-4,7, p=0,03), idade acima de 40 anos (OR = 1,05, 95% IC = 1,02-1,08, p<0,001) e icterÃcia (OR=2,9, 95% IC=1,5-5,8, p=0,002). Foi verificada considerÃvel associaÃÃo entre o emprego de anfotericina B e LRA (OR=18,4, 95% IC=7,9-42,8, p<0,0001), contudo o uso de glucantime foi associado a menor ocorrÃncia de LRA (OR=0,05, 95% IC=0,02-0,12, p<0,0001). A mortalidade geral foi 13,3% e foi mais alta nos pacientes que desenvolveram LRA (30,2% vs. 4,7%, p<0,0001). Os percentuais de mortalidade nas classes R, I e F foram respectivamente 40%, 20,8% e 35%. ConclusÃes. Os fatores de risco preditores de LRA em pacientes com LV foram sexo masculino, anfotericina B, idade acima de 40 anos e icterÃcia. Anfotericina B foi o fator mais importante de LRA na LV.

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