Prolonged or untreated intracranial pressure (ICP) can have devastating and life threatening effects. If left untreated, significant brain damage or death can occur as a result of a vicious cycle of destruction. Although clinical signs and symptoms are present with increases in intracranial pressure, ICP monitoring is the "gold standard" for assessment of intracranial pressure. Unfortunately, ICP monitoring is utilized only 50% of the time that it is indicated in the U.S. due to risks such as hemorrhage, infection, and technical malfunctions. Findings in the literature identify variables associated with infection risk when ICP monitoring devices are utilized. Factors associated with an increased risk of infection include indications for monitoring (subarachnoid or intraventricular hemorrhage), concurrent infection, duration and number of devices utilized, manipulation, and dislodgement. Other factors that may be associated with infection risk included corticosteroid use and location where the device is placed. Catheters impregnated with silver or antibiotics are associated with a decreased risk of infection. Variables deemed unimportant in regard to infection risk included age, gender, severity of illness, GCS score, CSF leak, who places the device, routine CSF sampling, prophylactic antibiotics, antibiotic irrigation, and prophylactic catheter exchange. None of the current literature is focused on nursing care. This is unfortunate, as the care nurses provide is integral to infection prevention associated with such devices. Future nursing research must address this lack of imperative information.

abstract: Intracranial pressure is an important parameter to monitor, and elevated intracranial pressure can be life threatening. Elevated intracranial pressure is indicative of distress in the brain attributed by conditions such as aneurysm, traumatic brain injury, brain tumor, hydrocephalus, stroke, or meningitis. Electrocorticography (ECoG) recordings are invaluable in understanding epilepsy and detecting seizure zones. However, ECoG electrodes cause a foreign body mass effect, swelling, and pneumocephaly, which results in elevation of intracranial pressure (ICP). Thus, the aim of this work is to design an intracranial pressure monitoring system that could augment ECoG electrodes. A minimally invasive, low-cost epidural intracranial pressure monitoring system is developed for this purpose, using a commercial pressure transducer available for biomedical applications. The system is composed of a pressure transducer, sensing cup, electronics, and data acquisition system. The pressure transducer is a microelectromechanical system (MEMS)-based die that works on piezoresistive phenomenon with dielectric isolation for direct contact with fluids. The developed system was bench tested and verified in an animal model to confirm the efficacy of the system for intracranial pressure monitoring. The system has a 0.1 mmHg accuracy and a 2% error for the 0-10 mmHg range, with resolution of 0.01 mmHg. This system serves as a minimally invasive (2 mm burr hole) epidural ICP monitor, which could augment existing ECoG electrode arrays, to simultaneously measure intracranial pressure along with the neural signals. This device could also be employed with brain implants that causes elevation in ICP due to tissue - implant interaction often leading to edema. This research explores the concept and feasibility for integrating the sensing component directly on to the ECoG electrode arrays. / Dissertation/Thesis / Masters Thesis Bioengineering 2015

A monitoração intraventricular da pressão intracraniana (PIC) com drenagem contínua do líquido cefalorraquiano (LCR) já é um procedimento difundido na prática da neurocirurgia e considerado de grande importância diagnóstica, terapêutica e prognóstica por sua precisão. Entretanto, por se tratar de um método invasivo, apresenta riscos potenciais de complicações, sendo a infecção a mais freqüente. O presente estudo teve como objetivo verificar e analisar as taxas de infecções decorrentes deste método de monitoração da PIC, assim como as taxas de seus fatores de risco. As informações obtidas através de prontuários e arquivo dos exames laboratoriais foram registradas em duas fichas de coleta de dados próprias e posteriormente submetidas a testes estatísticos como o de Kruskal-Wallis, de Mann-Whitney, de qui-quadrado, teste exato de Fisher e o coeficiente de correlação de Spearman. Obtidas as freqüências relativas e absolutas, médias e desvio-padrão, sendo de 5% o nível de significância utilizado para os testes. A população deste estudo foi de 79 pacientes dos quais 70.9% eram do sexo masculino com média de 33.7 anos, sendo que os diagnósticos presentes em 82.3% eram referentes ao trauma craniencefálico (TCE) seguido de tumores intracranianos e acidentes vasculares cerebrais (AVCs). Todos fizeram uso de antibioticoprofilaxia. A taxa de ventriculite foi de 26.6%, permanecendo o cateter, em média, 6.7 dias e apresentando taxas diárias desta infecção variáveis. Não encontramos associação estatisticamente significativa entre tempo de monitoramento e infecção, porém houve um aumento no índice diário de ventriculite após os três primeiros dias e picos no 6°, 9° e 12° dia indicando uma provável ligação não acumulativa ou linear. Outras variáveis avaliadas neste estudo que apresentaram associação direta com a ocorrência de ventriculite foram o sexo masculino, hemorragia subdural e infecções em outros sítios, principalmente a sepses. Variáveis como idade, procedimentos invasivos, TCE aberto, fístulas liquóricas, hemorragia intraventricular, múltiplas ventriculostomias, presença de PIC acima de 20mmHg, intercorrências durante a cateterização ou manutenção desta não apresentaram associação com a taxa ventriculite, no entanto muitas destas variáveis estiveram presentes em poucos casos dificultando uma conclusão definitiva. / Intraventricular monitoring of the intracranial pressure (ICP) with continuous drainage of cerebrospinal fluid (CSF) is already a widespread procedure in neurosurgical practice and considered as of great diagnostic, therapeutic and prognostic importance due to its precision. However, as it is an invasive method, it presents a potential risk of complications, the infection being the most frequent. The present study aims at verifying and analyzing the rates of infection originating from this monitoring method of ICP, as well as the rates of its risk factors. The information obtained from case histories and laboratory test files were recorded on two own separate data collection cards and later submitted to statistical tests like the Kruskal-Wallis, Mann-Whitney, Chi-Square, Fisher’s exact test, and Spearman correlation coefficients. Relative and absolute, average and standard deviation frequency were verified, 5% was the significance level utilized for the tests. The population of this study was of 79 patients, 70.9% of which were male averaging 37.7 years of age, this being so that the diagnostics present in 82.3% are related to traumatic head injury followed by intracranial tumors and stroke. All of them made use of antibioticprophylaxis. The ventriculitis rate was of 26.6 %, the catheter remaining, on average, 6.7 days and showing variable daily rates of this infection. We have not found a statistically meaningful association between monitoring time and infection, however there was an increase in the daily ventriculitis rate after the first three days and peaks on the 6th, 9th and 12th days showing a probable non-cumulative or linear link. Other variables evaluated in this study which presented a direct association with the occurrence of ventriculitis were the male sex, subdural hemorrhage and infections at other sites, mainly sepsis. Variables such as age, invasive procedures, open traumatic head injury, CSF leaks, intraventricular hemorrhage, multiple ventriculostomies, presence of ICP above 20mmHg, intercurrences during catheterization or its maintenance did not show association with the ventriculitis rate, nevertheless many of these variables were present in few cases making a definite conclusion difficult.

A monitoração intraventricular da pressão intracraniana (PIC) com drenagem contínua do líquido cefalorraquiano (LCR) já é um procedimento difundido na prática da neurocirurgia e considerado de grande importância diagnóstica, terapêutica e prognóstica por sua precisão. Entretanto, por se tratar de um método invasivo, apresenta riscos potenciais de complicações, sendo a infecção a mais freqüente. O presente estudo teve como objetivo verificar e analisar as taxas de infecções decorrentes deste método de monitoração da PIC, assim como as taxas de seus fatores de risco. As informações obtidas através de prontuários e arquivo dos exames laboratoriais foram registradas em duas fichas de coleta de dados próprias e posteriormente submetidas a testes estatísticos como o de Kruskal-Wallis, de Mann-Whitney, de qui-quadrado, teste exato de Fisher e o coeficiente de correlação de Spearman. Obtidas as freqüências relativas e absolutas, médias e desvio-padrão, sendo de 5% o nível de significância utilizado para os testes. A população deste estudo foi de 79 pacientes dos quais 70.9% eram do sexo masculino com média de 33.7 anos, sendo que os diagnósticos presentes em 82.3% eram referentes ao trauma craniencefálico (TCE) seguido de tumores intracranianos e acidentes vasculares cerebrais (AVCs). Todos fizeram uso de antibioticoprofilaxia. A taxa de ventriculite foi de 26.6%, permanecendo o cateter, em média, 6.7 dias e apresentando taxas diárias desta infecção variáveis. Não encontramos associação estatisticamente significativa entre tempo de monitoramento e infecção, porém houve um aumento no índice diário de ventriculite após os três primeiros dias e picos no 6°, 9° e 12° dia indicando uma provável ligação não acumulativa ou linear. Outras variáveis avaliadas neste estudo que apresentaram associação direta com a ocorrência de ventriculite foram o sexo masculino, hemorragia subdural e infecções em outros sítios, principalmente a sepses. Variáveis como idade, procedimentos invasivos, TCE aberto, fístulas liquóricas, hemorragia intraventricular, múltiplas ventriculostomias, presença de PIC acima de 20mmHg, intercorrências durante a cateterização ou manutenção desta não apresentaram associação com a taxa ventriculite, no entanto muitas destas variáveis estiveram presentes em poucos casos dificultando uma conclusão definitiva. / Intraventricular monitoring of the intracranial pressure (ICP) with continuous drainage of cerebrospinal fluid (CSF) is already a widespread procedure in neurosurgical practice and considered as of great diagnostic, therapeutic and prognostic importance due to its precision. However, as it is an invasive method, it presents a potential risk of complications, the infection being the most frequent. The present study aims at verifying and analyzing the rates of infection originating from this monitoring method of ICP, as well as the rates of its risk factors. The information obtained from case histories and laboratory test files were recorded on two own separate data collection cards and later submitted to statistical tests like the Kruskal-Wallis, Mann-Whitney, Chi-Square, Fisher’s exact test, and Spearman correlation coefficients. Relative and absolute, average and standard deviation frequency were verified, 5% was the significance level utilized for the tests. The population of this study was of 79 patients, 70.9% of which were male averaging 37.7 years of age, this being so that the diagnostics present in 82.3% are related to traumatic head injury followed by intracranial tumors and stroke. All of them made use of antibioticprophylaxis. The ventriculitis rate was of 26.6 %, the catheter remaining, on average, 6.7 days and showing variable daily rates of this infection. We have not found a statistically meaningful association between monitoring time and infection, however there was an increase in the daily ventriculitis rate after the first three days and peaks on the 6th, 9th and 12th days showing a probable non-cumulative or linear link. Other variables evaluated in this study which presented a direct association with the occurrence of ventriculitis were the male sex, subdural hemorrhage and infections at other sites, mainly sepsis. Variables such as age, invasive procedures, open traumatic head injury, CSF leaks, intraventricular hemorrhage, multiple ventriculostomies, presence of ICP above 20mmHg, intercurrences during catheterization or its maintenance did not show association with the ventriculitis rate, nevertheless many of these variables were present in few cases making a definite conclusion difficult.