published_or_final_version / Nursing Studies / Master / Master of Nursing

Ventilator-associated pneumonia (VAP) is a serious complication in critically ill patients; it can prolong intubation, increase intensive care unit and hospital length of stay, and increase mortality to twice the level of patients who do not develop VAP. The purpose of this project was to determine the effect of an evidence-based educational program to prevent VAP on ICU nurses' actual and documented practices for preventing VAP. The research questions addressed whether an educational program focused on VAP prevention will affect critical care nurses' compliance with a VAP prevention bundle, and whether the education will result in maintenance of a rate of zero cases of VAP per 1000 ventilator days. Data will be collected from all ICU patients intubated more than 24 hours and will include: (a) the frequency of oral care, (b) head-of-bed elevation of 30â??45 degrees, (c) daily sedation vacation, (d) assessment of readiness for extubation, and (e) whether prophylaxis for deep vein thrombosis and for peptic ulcer disease was ordered. Observations of care will verify the accuracy of nurses' documentation in the medical record. A survey will assess nurse satisfaction with the educational program. Paired t tests will be used to compare the compliance of the nurses with each element of oral care and hygiene practices before and after the intervention. Analysis of variance will be calculated on the mean duration of ventilation, mean ICU and hospital length of stay, mortality before discharge, patient acuity, and rates of VAP per 1000 ventilator days. The goal of this project is a compliance rate of 90% or greater with the elements of the VAP prevention bundle, leading to decreased ventilator and ICU days, decreased morbidity, decreased mortality, and lower emotional distress. Positive social change will be accomplished through an immediate improvement in the lives of VAP-prone individuals.

Pulmonary aspiration in mechanical ventilation occurs despite appropriate inflation of the tracheal tube cuff. After anaesthesiath is can causep ostoperative and, in critically ill patients, ventilator-associated pneumonia. Cuff over-inflation exerts excessive pressure on the tracheal mucosa causing injury. High volume low pressure (HVLP) cuffs permit wall pressure control as the intracuff pressure (CP) is the tracheal wall pressure (TWP). Unfortunately, at the cuff wall, folds and channels and, therefore, fluid leakage occur. Low volume high pressure (LVHP) cuffs develop neither folds nor associated leakage, but TWP is not easily inferred from CP and excessive pressures can result in tracheal injury. This thesis examines the problem of aspiration in a model, in anaesthetised patients and in the critically ill. In the model, protection against leakage resulted from positive end-expiratory pressure and cuff lubrication. Two tracheal cuff prototypes are introduced. Firstly, the compliant HVLP cuff is one with a tapered shape made of highly compliant material. Within the model this produced a circumferential band at the cuff wall without folds thus effectively eliminating channels and leakage. Secondly, the prototype pressure limited cuff (PLC) is a latex LVHP cuff with inflation characteristics such that TWP can be inferred from CP and maintained at an acceptable level. Within the model the PLC prevented leakage at acceptable TWPs. For clinical use a constant pressure inflation device is required to provide uninterrupted protection, although notably HVLP cuffs allow leakage despite this. The PLC prevented dye aspiration in 100% of tracheally intubated critically ill patients compared with 13% of the control HVLP group (p<0.01). A silicone cuff with similar inflation characteristics, yet improved biocompatability and shelf life, prevented dye aspiration in 100% of patients with tracheostomies compared to 0% of the HVLP control group (p=0.001). HVLP cuff lubrication delayed dye aspiration for 1 to 5 days (p<0.05).

No description available.

Patients with an impaired reflexive cough response are at increased risk of pneumonia. This study examined the correlation between cough sensitivity to citric acid and radiographic features of airway compromise. Eighty patients referred for a radiographic assessment of swallowing at an acute hospital over an 8-month period participated in the study. Nebulised citric acid diluted in 0.9% sodium chloride was inhaled through a facemask at four concentrations to assess cough sensitivity. These data were then compared to Penetration Aspiration Scale scores based on radiographic swallowing studies. There was a statistically significant correlation between cough response/lack of response and the radiographic features of airway compromise; that is, patients who had a weak or absent response to inhalation of citric acid were also likely to aspirate silently during radiographic assessment. Sensitivity for identifying absent cough was found to be high at all 4 concentrations (0.750, 0.833, 0.941, 1.000), however specificity was consistently quite low (0.344, 0.456, 0.238, 0.078). The significant findings of this research suggest that clinicians adopting cough reflex testing into their clinical practice will have a reliable screen for silent aspiration at bedside. Clinicians will be able to identify patients who require instrumental assessment and are at high risk of pneumonia. This will likely, in turn, decrease length and cost of hospital admissions as well as decrease aspiration pneumonia related morbidities.

The aim of this thesis was to examine the use of modelling techniques in the economic evaluation of selective decontamination of the digestive tract (SDD), used to prevent intensive care unit (ICU) acquired pneumonia. The need for evidence for the effectiveness and cost effectiveness of technologies used in intensive care was highlighted through an examination of the literature. The clinical and economic issues pertinent to ICU-acquired pneumonia and SDD were described. It was suggested that an economic evaluation of SDD was required. An evaluation using modelling techniques was proposed. A secondary economic evaluation of SDD was carried out, utilising a decision-analytic model and published clinical and economic evidence to derive cost/outcome ratios. This analysis showed that SDD could be a dominant therapy, but improved economic and long term outcome evidence was required to increase the robustness of conclusions. This thesis concentrated on improving the economic evidence. A national survey of SDD use provided information on clinical practice. A prospective observational study was carried out at two British ICUs to obtain evidence on the economic impact of ICU-acquired pneumonia. The impact of infection and confounding factors on resource use was handled quantitatively, using regression techniques. It was found that ICU-acquired pneumonia significantly increased length of ICU stay. These two sets of empirical data were used in a revised economic evaluation of SDD. SDD was found to be a dominant therapy at both centres. Uncertainty around cost/outcome ratios was considered to be decreased, or at least quantified, by this primary economic evidence. This thesis concludes that modelling has a place in economic evaluation in intensive care, if rigorous methods are used. It has also demonstrated that current, reliable and applicable economic evidence is a prerequisite to any economic evaluation, if it is to be included in the decision-making process.

Four strains of the swine pathogen Actinobacillus pleuropneumoniae, namely, the type strain (ATCC 27088), the "reference" strain of biotype 2 (Bertschinger 2008/76) and two additional biotype 1 strains, strain BC181, which is less virulent than the type strain, and strain K17 (reference strain of serotype 5A), which was isolated from a lamb, were investigated with respect to iron acquisition. All four strains produced iron-repressible outer membrane proteins. However, only strains ATCC 27088 and Bertschinger 2008/76 could acquire iron from porcine transferrin. No organism could utilize human, bovine or ovine transferrin, or ovine or porcine lactoferrin. Haemoglobin supported good growth of all strains except K17 (which also failed to acquire iron from haemin). In all cases, iron acquisition from transferrin or haemoglobin required direct contact between the organisms and the proteins. Total membranes derived from iron-restricted organisms were subjected to an affinity isolation technique based on biotinylated porcine transferrin and streptavidin-agarose, and the following polypeptides were isolated: 99 kDa and 64 kDa from strain ATCC 27088; 93 kDa from strain Bertschinger 2008/76; 95 kDa (trace amounts) and 60 kDa from strain BC181; none from strain K17. These polypeptides appear to be transferrin receptor components. The 99 kDa polypeptide (TBPl) from the type strain was purified by SDS-PAGE and transferred electrophoretically onto polyvinylidene difluoride membrane. The N-terminal amino acid sequence of the polypeptide was determined commercially. A commercially-synthesized oligonucleotide probe was used to clone the gene encoding the TBPl of the type strain in competent Escherichia coli DH5$ alpha$ cells.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.

Thesis (doctoral)--Lund University, 1995. / Added t.p. with thesis statement inserted.

Thesis (doctoral)--Lund University, 1995. / Added t.p. with thesis statement inserted.