Diss. (sammanfattning) Umeå : Univ., 2007. / Härtill 4 uppsatser.

The abdominal aorta (AA) in man is a vulnerable artery prone to atherosclerosis as well as aneurysmatic dilation. The underlying aortic composition, mechanical properties as well as the mechanisms responsible for age-related changes and vascular disease are however largely unknown. The aims of this study were 1) to characterize the age- and gender-related changes of the aortic wall components in vivo, using a mechanical model based on ultrasound measurements of pulsatile aortic diameter changes combined with intra-arterial pressure; 2) to validate ultrasound measurements of diameter and intima-media thickness (IMT) of the AA in order to calculate wall stress; 3) to study the stress driven remodeling response of the aortic wall in healthy individuals and the influence of age and gender; and 4) to study wall stress and remodeling of the AA in diabetic patients in order to elucidate the protective influence of diabetes on abdominal aortic aneurysm formation. The stiffness of the isotropic material (mainly elastin) increased in males despite the known decrease in elastin content with age. Further, an exponential increase in stiffness of the anisotropic material (mainly collagen) in males at high physiological pressure was found. This might be due to changed isoforms of collagen and increased glycation with age. Females were less affected than males. The reproducibility of the ultrasound measurements of diameter and IMT in the AA was acceptable (CV; 4% and 11% respectively), making it possible to calculate circumferential aortic wall stress in vivo. The age-related remodeling of the arterial wall led to increased diameter, and compensatory thickening of the wall preventing the circumferential wall stress from increasing in the common carotid artery of males and females, and the AA of females. However, the compensatory increase in wall thickness was defect in the male AA, where stress increased with age. Pulsatile stress influenced the material parameters of the AA, leading to increased stiffness of anisotropic material (mainly collagen), whereas stiffness of isotropic material (mainly elastin) was unaffected. Patients with diabetes mellitus had increased aortic wall thickness than controls, generating less circumferential stress. This coincides with the known reduction of abdominal aortic aneurysms in diabetic patients and may act as a protective factor.

Intraoperativ kommunikation är av stor betydelse för patientsäkerheten. Operationsteamet består av flera olika yrkeskategorier som alla har ett gemensamt mål där patienten är i fokus. För att underlätta kommunikationen mellan och inom olika professioner i olika överrapporteringstillfällen finns kommunikationsverktyg att tillgå. SBAR och WHO´s checklista för säker kirurgi är beprövade verktyg. Syftet med studien är att beskriva hur teamet på operationssal kan skapa god kommunikation mellan/inom olika professioner intraoperativt. Metoden i studien är en allmän litteraturöversikt, ett strukturerat arbetssätt för att skapa en bild av det valde området. Resultatet redovisas i tre huvudkategorier och sex underkategorier. Huvudkategorier är trygghet, samförstånd och dialog.  Trygghet beskrivs både för patienten och för personalen där kommunikationen är det centrala. Kommunikationen mellan de olika professionerna och deras uppträdande intraoperativt påverkar patientens trygghet. Familjära team med samarbete, vänlighet och respekt för varandra ger samförstånd och ökad patientsäkerhet. Informationsutbyte med hjälp av SBAR och WHO´s checklista för säker kirurgi ökar patientsäkerheten då risken för att viktig information faller bort minskar. Perioperativa sjuksköterskor har ett gemensamt ansvar att värna om patientens autonomi och individuella behov. Patientens behov är i fokus för den intraoperativa vården. Vårdpersonal bör göras medveten om att kommunikationsbrister kan medföra patientlidande.

Background: Excessive gestational weight gain (GWG) is common in developed countries and is associated with an increased risk of maternal and offspring morbidity. Evidence regarding efficacy and safety of antenatal lifestyle intervention is limited in terms of both systematic reviews and original trials. This thesis is based on the need to further explore this research area. Objectives: To assess and grade current evidence and evaluate short and long-term effects of an antenatal lifestyle intervention on women and their offspring Materials: Controlled trials of intervention publishedbefore August 2009 were systematically searched and reviewed. A randomized controlled trial (RCT) including 445 healthy women aged >18 years with a body mass index (BMI) ≥19 and ≤16 weeks pregnant and their offspring was performed during 2007-2015 in Örebro Region, Sweden. Methods: The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system was used for review. Our RCT (called the VIGA trial) compared standard care with a composite intervention consisting of education, application of a personalized weight graph, prescription of exercise and more frequent monitoring of weight. Standardized measures of weight and height in offspring waere analysed based on World Health Organization (WHO) Child Growth Standards. Results: Quality of evidence across the studies published pre-August 2009 was concluded to be very low. Our intervention significantly reduced mean GWG (kg) but the proportion of women with excessive GWG, according to recommendations, was not significantly reduced. Short- term postpartum weight retention (PPWR) was significantly lower after the intervention but no significant difference remained 1 year after delivery. Offspring mean BMI z-scores or proportion of obesity did not differ between study groups at either birth or age 5. Conclusions: The antenatal lifestyle intervention reduced mean GWG and short-term PPWR but no long-term effects on maternal weight retention or offspring obesity were seen. Alternative modes and timing of intervention should be considered in future research. Reducing the prevalence of pre-conception obesity must still be considered the primary means to improve maternal and fetal outcome.

Transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) imaging are two commonly used imaging modalities for evaluating the size and function of the heart. There are advantages and disadvantages associated with both modalities when examining the right ventricle (RV). The RV is positioned partly behind the sternum and lung, sometimes causing shadows in the TTE images. This along with the complex shape of the RV makes volume calculations challenging by 2D TTE. CMR is considered to be the reference method for volume calculations of the ventricles. The valve separating the RV from the right atrium is however often oblique compared to the valve separating the left ventricle from the left atrium. This complicates RV volume calculations using conventional CMR short-axis stack images. The aim of this thesis was to find ways to improve the RV stroke volume and ejection fraction calculations using TTE and CMR. A method, transferring the position of the tricuspid plane from RV long-axis images to short-axis images, was developed to improve the separation of the right atrium from the RV when calculating RV stroke volumes by CMR. The method provided calculations of RV stroke volumes with good agreement to reference volumes. Further, the movements contributing to the RV stroke volume was studied aiming to find new ways of calculating RV stroke volumes and ejection fraction by TTE. A model for RV stroke volume and ejection fraction calculations was evaluated showing underestimation of stroke volumes by TTE compared to CMR, which probably depend on differences in distance measurements using the two modalities. The model provided, however, promising results for ejection fraction calculations which was validated in a study of 37 participants that covered a wide range of EF.

Radiography is a common radiologic investigation despite abundant evidence of its limited diagnostic value. On the other hand, computed tomography (CT) has a high diagnostic value and is widely considered to be among the most important advances in medicine. However, CT exposes patients to a higher radiation dose and it might therefore not be acceptable simply to replace radiography with CT, despite the powerful diagnostic value of this technique. At the expense of reduced CT image quality, which could be adjusted to the diagnostic needs, low-dose CT of abdomen and lumbar spine can be performed at similar dose to radiography. The aim of the current thesis project was to evaluate low-dose CT of the abdomen and lumbar spine and to compare it with radiography. The hypothesis was that CT would give better image quality and diagnostic information compared to radiography at similar dose levels. Firstly, the diagnostic accuracy of low-dose CT of the abdomen was evaluated. Results showed that low-dose CT of abdomen has a high sensitivity and specificity compared to radiography, i.e., it has higher diagnostic accuracy. Similar results were obtained from our systematic review. Secondly, in a phantom study, an ovine phantom was scanned at various CT settings. The image quality was evaluated to obtain a protocol for the optimal settings for low-dose CT of lumbar spine at 1 mSv. This new protocol was then used in a clinical study to assess the image quality of low-dose CT of the lumbar spine and compare it to radiography. Results showed that low-dose CT has significantly better image quality than radiography. Finally, the impact of Iterative reconstruction (IR) on image quality of lumbar spine CT was tested. Iterative reconstruction is a recent CT technique aimed to reduce radiation dose and/or improve image quality. The results showed that the use of medium strength IR levels in the reconstruction of CT image improves image quality compared to filtered back projection. In conclusion, low-dose CT of the abdomen and lumbar spine, at about 1 mSv, has better image quality and gives diagnostic information compared to radiography at similar dose levels and it could therefore replace radiography.

This thesis aims to present a multi-dimensional instrument for self-assessment of progress in postoperative recovery. The author employs different research paradigms and methodologies to achieve this aim. Walker and Avant’s approach to concept analysis was used to examine the basic elements of postoperative recovery (Study I). The analysis identified different recovery dimensions and developed a theoretical definition showing postoperative recovery to be an energy-requiring process of returning to normality and wholeness, defined by comparative standards. Fourteen patients and 28 staff members participated in individual and focus group interviews aimed at describing patient and staff experiences of patient recovery (Study II). The essence of the postoperative recovery process was described as a desire to decrease unpleasant physical symptoms, reach a level of emotional wellbeing, regain functions, and re-establish activities. In Study III, 5 dimensions and 19 items were identified as a part of the operationalization process of the concept postoperative recovery. Fifteen staff members and 16 patients participated in the evaluation of content validity. On average, 85% of the participants considered the items as essential to the recovery process. In a test run of the questionnaire, 14 of 15 patients considered the questionnaire to be easy to understand and easy to complete. Twenty-five patients participated in the evaluation of intra-patient reliability. Percentage agreement (PA), systematic disagreement (RP, RC), and individual variability (RV) between the two assessments were calculated. PA measures ranged from 72% to 100%. The observed disagreement could be explained mainly by systematic disagreement. In total, 158 patients participated in the evaluation of construct validity, the ability to discriminate between groups, and the investigation of important item variables (Study IV). A rank-based statistical method for evaluation of paired, ordered categorical data from rating scales was used to evaluate consistency between the assessments of the Postoperative Recovery Profile (PRP) questionnaire and a global recovery scale. The number of months needed by participants to be regarded as fully recovered was studied by means of recovery profiles displayed by the cumulative proportion of recovered participants over time. A ranking list based on the participant’s appraisal of the five most important item variables in the PRP questionnaire was compiled to illustrate the rank ordering of the items. In comparing the assessments from the PRP questionnaire and the global recovery scale, 7.6% of all possible pairs were disordered. Twelve months after discharge 73% in the orthopaedic group were regarded as fully recovered, compared to 51% of the participants in the abdominal group (95% CI: 6% to 40%). The pain variable appeared among the top five most important items on eight measurement occasions, of eight possible, in both study groups. In conclusion, the PRP questionnaire was developed and support was given for validity and reliability. The questionnaire enables one to evaluate progress in postoperative recovery.

Malignant gliomas grow infiltrative in the brain and can therefore not be completely removed by neurosurgical means. However, for an optimized oncological treatment it has proven useful to resect as much as possible of tumor. The identification of the tumor in the marginal zone is difficult but crucial. Studies have shown that visualization of the specific enhancement of 5-aminolevulinic acid(5-ALA) in the tumor can help to maximize the resection. The Department of Biomedical Engineering, Linköping University, has developed an optical hand-held probe (HHP) to identify tumor tissue with a high sensitivity by means of fluorescence spectroscopy. The technical design and the optical properties of the probe were gradually developed in a standard neurosurgical setting during resection of malignant gliomas. The device could easily be implemented in the operating room, meeting all requirements in terms of sterile handling and without interference of any kind with other equipment. The integration of the device in a navigation system and its use in combination with a blue light surgical microscope were simple. Measurements in 27 operations during resection of malignant gliomas were compared to results from biopsies from the same tumor locations. The equipment was tested as a stand-alone device (n = 180), integrated in a navigation system or in combination with the blue light microscope (n = 190). A ratiocal culated from the measurements enabled objective and comparable values for different tissue types, in correspondence with the findings from the histopathological examinations and in accordance with the navigation system as well as with the surgical microscope.The marginal zone was explored and tumor fluorescence could be identified beyond the fluorescence as seen through the microscope. A higher sensitivity of the HHP was confirmed; the specificity was lower. The combined use of the HHP with a navigation system and with asurgical microscope was beneficial. / Maligna hjärntumörer växer infiltrerande i hjärnan och kan därförinte helt avlägsnas genom kirurgiska operationer. För en optimerad behandling har det emellertid visat sig vara av värde att avlägsna såmycket som möjligt av tumörvävnaden. Identifiering av tumören i gränszonen är mycket svårt, men avgörande. Studier har visat att visualisering av den specifika laddningen av 5-aminolevulinsyra (5-ALA) i tumören kan bidra till att maximera resektionen. Institutionen för Medicinsk Teknik (IMT) på Linköpings universitet,har utvecklat en liten handhållen optisk prob (HHP) för att identifiera tumörvävnad med hög känslighet med hjälp avfluorescens-spektroskopi. Den tekniska konstruktionen och de optiska egenskaperna hos proben utvecklades stegvis genom testning i flera neurokirurgiska operationer för resektion av maligna gliom. Utrustningen uppfyllde alla krav när det gällde steril hantering i operationssalen och kunde användas utan störningar av något slag med annan operationsutrustning. Integreringen i ett navigerings-system och användningen i kombination med ett kirurgiskt mikroskop för fluorescens-styrd kirurgi var oproblematiska. Mätningar under 27 operationer vid resektion av maligna gliom jämfördes med resultat från biopsier från samma tumörtagningsställen. Utrustningen testades såväl som en fristående enhet (n = 180) och som integrerad i ett navigationssystem eller i kombination med mikroskopet (n =190). En särskild kvot beräknad ur mätningarna möjliggjorde objektiva och jämförbara värden för olika vävnader, i överensstämmelse med resultaten från de vävnadspatologiska undersökningarna och i överensstämmelse med navigationssystemet såväl som med det kirurgiska mikroskopet. Tumörernas gränszon undersöktes och tumörfluorescens kunde identifieras bortom fluorescensen som mikroskopet visade. En högre känslighet hos HHP bekräftades; specificiteten var lägre. Den kombinerade användningen av HHP med ett navigationssystem och med ett kirurgiskt mikroskop visade sig vara fördelaktig.

Gällande riktlinjer för preoperativ fasta beskriver att patienter med liten risk för aspiration kan inta fast föda fram till sex timmar och klara drycker fram till två timmar före start av anestesi. Studier har visat att många patienter fastar längre, vilket kan ha negativ inverkan både fysiologiskt och på välbefinnandet som till exempel dehydrering, törst, illamående, huvudvärk och nedsatt insulinkänslighet. Syftet med studien var att kartlägga och beskriva preoperativa fastetider, dryckintag samt förekomst av törst hos patienter planerade för elektiv kirurgi. Strukturerade intervjuer genomfördes under fem dagar med 50 patienter som rekryterades konsekutivt på två preoperativa avdelningar. Resultaten visade att majoriteten av patienterna instruerats att inta klara drycker fram till två timmar före start av anestesi. Fastetider hos patienter med strikt fasta varierade mellan 7,75 till 13,25 timmar (median 10 och dryckintag mellan 0,5 till 7,5 glas (medelvärde 3,14; standardavvikelse 1,98). Fastetider hos patienter med flytande fasta varierade mellan 0,75 till 11,25 timmar (median 3,5 och dryckintag mellan 1 till 9 glas (medelvärde 4,31; standardavvikelse 1,91). Av de 50 intervjuade patienterna uppgav 44 % att de upplevde törst. Studiens resultat visade på en stor variation i fastetider och dryckintag där de äldsta patienterna tenderade att fasta länge och inta små mängder dryck preoperativt. / Existing guidelines for preoperative fasting means that patients with a minimal risk of aspiration can take solid food until six hours, and clear drinks until two hours before start of anesthesia. Studies have shown that many patients are fasting longer, which may be detrimental both physiologically and on wellbeing, for example, dehydration, thirst, nausea, headache and reduced insulin sensitivity. The purpose of this study was to map and describe fasting times, beverage intake and the incidence of thirst preoperatively in patients who were undergoing elective surgery. Structured interviews were conducted over five days with 50 patients who were enrolled consecutively in two preoperative departments. The results showed that fasting times in patients with strict fasting ranged from 7.75 to 13.25 hours (MD 10) and beverage intake between 0.5 to 7.5 glasses (3.14 SD 1,98). Fasting times in patients with float fasting ranged from 0.75 to 11.25 hours (MD 3,5) and beverage intake between 1 to 9 glasses (4,31 SD 1,91). Of the 50 interviewed patients, 44 % said they experienced thirst. The results indicated a wide variation in preoperative fasting times and beverage intake, where the oldest patients tended to have long duration of fasting and intake of small amounts of beverage preoperatively. / <p>2010 felaktigt årtal titelsida</p>

Bakgrund: I litteraturen finns evidens att använda dubbla lager av operationshandskar vid all kirurgi för att förebygga smittspridning mellan patient och personal samt för att förebygga vårdrelaterade infektioner. Operationshandskar kan ha olika tjocklek och taktil känsla beroende på latex eller latexfritt material. Trots att evidens finns att använda dubbla lager operationshandskar förekommer variation i användandet. Syfte: Syftet med studien var att undersöka om operationssjuksköterskor och kirurger väljer enkla eller dubbla handskar vid operationer, samt hur de motiverar sitt val. Metod: Operationssjuksköterskor och kirurger från två operationsavdelningar i Mellansverige undersöktes i en tvärsnittsdesign med intervjustödda enkäter. Flera deltagare intervjuades flera gånger. Resultat: Totalt inkluderades 66 deltagare i studien och 137 intervjuer genomfördes. Nästan hälften av deltagarna motiverade sitt val av handskar med rutin eller vana. Vid samtliga ortopediska operationer användes dubbla handskar. Enkelt lager av handskar användes i högre grad då endast latexfria handskar fanns att tillgå, och den dominerande motiveringen var då att det var mer svårarbetat med dubbla handskar. Slutsats och klinisk betydelse: Användandet av enkla respektive dubbla handskar skiljer sig mellan verksamheterna och mellan yrkeskategorierna. Dubbla handskar användes av samtliga deltagare på den avdelning där skriftliga riktlinjer angående dubbla handskar fanns formulerade. Enkla handskar användes i högre grad då endast latexfria handskar fanns att tillgå. Resultatet i föreliggande studie indikerar att riktlinjer angående dubbla handskar, samt latexfria handskars sämre taktila förmåga kan ha betydelse för hur operationspersonal väljer operationshandskar. / Background: In the literature, there is evidence of the usage of double layered surgical gloves during all surgical procedures in order to prevent the spread of infection between the patient and medical personnel, as well as, to prevent clinical infections. Double layered surgical gloves can have different thickness and tactile feeling depending on latex or latex-free material. Aim: To investigate if operating room nurses and surgeons choose single or double gloving for operations, as well as, how they motivate their choices. Method: Operating room nurses and surgeons from two different operation departments in the middle of Sweden were examined in a cross-sectional design with interview-supported questionnaires. Some participants were interviewed several times. Results: In total, 66 participants were included in the study and 137 interviews were conducted. Almost half of the participants motivated their choice of gloves routinely or habitually. In all orthopedic operations, double gloves were used. Conclusion and clinical implications: The usage of single as opposed to double-gloving differs between departments and between different categories of profession. The majority of participants chose to use double gloves. Double gloves were more frequently used on the ward where written guidelines regarding double gloves were formulated. Single gloves were more commonly used in the pediatric surgery department, where only latex-free gloves were available for use. The result in the present study indicates that guidelines regarding double gloves can be significant for how operation personnel choose surgical gloves.