Utjecaj tehnike zatvaranja reza cistotomije na maksimalni intravezikalni tlak u svinjskom mokraćnom mjehuru

master's thesis

• Title (english): Influence of the cystotomy incision closure technique on the maximum intravesical pressure in porcine bladder
• Author: Ivana Vranić
• Mentor: Janoš Kodvanj (mentor)
• Mentor: Dražen Vnuk (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2018-12-13, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

Cistotomija je kirurški zahvat pri kojem se reže stijenka mokraćnog mjehura. Najčešće se koristi u humanoj i veterinarskoj medicini za kirurško liječenje mokraćnih kamenaca. Rez cistotomije potrebno je zatvoriti i za to se koriste različite kirurške tehnike. Standardne tehnike su korištenje resorbirajućih monofilamentnih materijala za šivanje korištenjem pojedinačnog čvorastog ili produžnog šava s čvoranjem na početku i na kraju šava. Zbog nedostataka standardne tehnike zatvaranja reza cistotomije, kao što su produženo vrijeme šivanja i prisutnost čvorova koji mogu lokalno iritirati tkivo unutar abdomena, potrebno je uvođenje novih tehnika. U ovom radu, osim standardne tehnike, ispitan je utjecaj zatvaranja reza cistotomije kožnim staplerom i koncem s postranim kukicama na vrijednost maksimalnoga intravezikalnog tlaka i vrijeme potrebno za zatvaranje reza, a statičkim vlačnim testom ispitana je vlačna čvrstoća rane ovisno o tehnici zatvaranja. Kako bi se dobio bolji uvid u način popuštanja rane zatvorene različitim tehnikama, tijekom provedbe statičkoga vlačnog ispitivanja pomaci u području rane mjereni su optičkim mjernim sustavom Aramis. Osim toga, ispitana su i mehanička svojstva tkiva svinjskog mjehura u dva međusobno okomita smjera. Rezultati ispitivanja pokazali su da je razlika u maksimalnom intravezikalnom tlaku između pojedinih skupina uzoraka statistički značajna. Za uzorke zatvorene staplerom i koncem s postranim kukicama zabilježene su manje vrijednosti maksimalnoga intravezikalnog tlaka od onih zatvorenih standardnim načinom. Usporedbom vremena potrebnoga za zatvaranje reza cistotomije uočeno je da između standardne i tehnike zatvaranja korištenjem konca s postranim kukicama nema statistički značajne razlike, a zatvaranje reza staplerom znatno je brže. Statičkim vlačnim ispitivanjem čvrstoće rane uočeno je da nema statistički značajne razlike, ovisno o tehnici zatvaranja reza. Analiza mehaničkoga ponašanja tkiva svinjskog mjehura u dva međusobno okomita smjera pokazala je da postoji statistički značajna razlika u mehaničkim svojstvima ovisno o mjestu uzimanja uzorka. Maksimalni intravezikalni tlak izmjeren nakon šivanja reza cistotomije standardnom tehnikom bio je najveći i opravdao je primjenu standardne tehnike svakodnevno korištene pri zatvaranju reza cistotomije, iako je fiziološki intravezikularni tlak u svinje niži nego vrijednosti izmjerene nakon zatvaranja reza cistotomije staplerom ili koncem s postranim kukicama.

Abstract (english)

Cystotomy is a surgical procedure in which the bladder wall is opened, and is a common medical practice for the surgical treatment of the bladder. Various surgical techniques are used to close the cystotomy incision. Standard techniques imply the use of absorbable monofilament suturing materials, using simple knots or a simple continuous suture pattern with knots at the beginning and end of the suture. Due to a lack of standard suturing techniques for the cystotomy cut, such as an extended suturing time and presence of knots that can locally irritate tissues within the abdomen, there is a need for new techniques. This paper investigates the impacts of closure of the cystotomy incision, in addition to standard suturing methods, using skin staplers and barbed sutures, on the values of maximum intravesical pressure and the time needed to close the wound, while static tensile tests were used to investigate the tensile strength of the wound with regard to the closure technique. In order to obtain better insight into the ways wounds strength following different closure techniques, during the static tensile test, displacements in the wound area were measured using the Aramis optical measurement system. Additionally, the mechanical properties of porcine bladder tissue were tested in two perpendicular directions. The testing results indicated that there was a statistically significant difference in the maximum intravesical pressure between samples. Samples closed with a stapler and barbed suture achieved lower values of maximum intravesical pressure than those samples closed with standard suturing techniques. A comparison of the time needed to close the cystotomy cut showed no statistically significant differences between the standard techniques and closure technique using barbed suture, while closure using the skin stapler was significantly faster. Static tensile testing of wound strength indicated no statistically significant differences with regard to wound closure technique. Analysis of the mechanical behaviour of porcine bladder tissue in two perpendicular directions indicated that there was a statistically significant difference in the mechanical properties with regard to the sampling site.

The maximum intravesical pressure measured following suturing of the wound was highest using standard techniques, and justified the use of the standard techniques used regularly in the closure of cystotomy cuts, even though the physiological intravesical pressure in porcine was lower than the values measured after the closure of the cystotomy cut using a skin stapler or barbed suture.

• Keywords: svinjski mokraćni mjehur; cistotomija; stapler; konac s postranim kukicama; vlačno ispitivanje
• Keywords (english): porcine bladder; cystotomy; stapler; barbed suture; tensile testing
• Language: croatian
• URN:NBN: urn:nbn:hr:235:875001
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-22 22:36:03