A laparoscopia é técnica cirúrgica minimamente invasiva na qual se utiliza um laparoscópio inserido por via transabdominal por onde é possível inspecionar visualmente a superfície das vísceras e do peritônio e realizar procedimentos cirúrgicos. Até o momento, a laparoscopia diagnóstica em equinos em estação através da fossa paralombar exige que sejam realizados dois procedimentos (um de cada lado do animal) para visualização significativa da cavidade peritoneal, além do uso de laparoscópio específico. Com o intuito de desenvolver a laparoscopia diagnóstica em equinos em estação por acesso único, foi desenvolvida uma cânula óptica com espiral sem trocarte de 60 cm de comprimento que tem o objetivo de promover maior segurança ao acesso laparoscópico (penetração radial sem trocarte e sob visualização) e sustentação ao endoscópio flexível para que seja possível realizar exploração significativa de ambos os hemisférios abdominais dorsais por apenas uma das fossas paralombares. Foram utilizados seis equinos adultos, sendo três machos e três fêmeas, submetidos a jejum alimentar de 24 a 30 horas. Amostras de sangue para realização de hemograma e dosagem de fibrinogênio foram obtidas no D-Pré, D4 e D7. Os equinos foram sedados com cloridrato de detomidina, seguido de bloqueio anestésico local com cloridrato de lidocaína infundida na musculatura e tecido subcutâneo do local de incisão no centro da fossa paralombar. O procedimento cirúrgico teve início com incisão cutânea de cerca de 2 cm de comprimento. As camadas musculares da região foram afastadas através da rotação da cânula em sentido horário e o afastamento dos tecidos foi acompanhado pelas imagens produzidas pelo endoscópio flexível e reproduzidas no monitor. Logo da perfuração do peritônio, foi iniciada a exploração da cavidade. Após a exploração do lado ipsilateral ao local de acesso, foi realizada a transposição do conjunto cânula/endoscópio ventralmente à porção caudal do cólon descendente seguida de exploração do lado contralateral. Terminado o exame, o conjunto foi removido através da rotação da cânula no sentido anti-horário e a incisão de pele foi suturada junto ao subcutâneo. A movimentação da cânula entre os órgãos abdominais mostrou-se segura, no entanto, em dois animais houve lesão iatrogênica ao baço, evidenciada por discreta hemorragia local. Foi possível a identificação da maioria das estruturas abdominais descritas na literatura por procedimento laparoscópico em equinos em estação pelo acesso único. Em cinco dos seis animais houve formação de enfisema subcutâneo adjacente às feridas cirúrgicas. Os parâmetros hematológicos dos animais mantiveram-se dentro dos limites estabelecidos para a espécie, com exceção dos leucócitos totais, neutrófilos segmentados e fibrinogênio que demonstraram pequenas variações. A abordagem proposta mostrou-se viável e tem o potencial de tornar o procedimento mais rápido, prático e seguro e menos invasivo e oneroso, fomentando a aplicação da laparoscopia diagnóstica na espécie equina. / Laparoscopy is a minimally invasive surgical technique by using a laparoscope inserted through the abdominal wall where it is visually possible to inspect visceral surfaces and peritoneum, and to perform surgical procedures. Up to now, diagnostic laparoscopy in standing horses through the paralumbar fossa requires two procedures to be performed (one on each side of the animal) in order to significantly see the peritoneal cavity, in addition of using specific laparoscope. With the purpose to develop a diagnostic laparoscopy in standing horses through a single access, a trocarless threaded visual cannula 60 cm length was designed with the aim to promote higher safety to laparoscopic access (radial penetration without trocar and under visualization), and support to a flexible endoscope so that a significant exploration of both dorsal abdominal hemispheres through only one of the paralumbar fossa is possible to perform. Six mature horses were used: three males and three females. Food was withheld for 24 to 30 hours before surgery. Blood samples to perform complete blood count and fibrinogen metering were obtained in D-Pre, D4, and D7. The horses were sedated with detomidine hydrochloride, followed by local anesthesia blockade with lidocaine hydrochloride infused in the muscle and subcutaneous tissue at the incision place in the center of the paralumbar fossa. The surgical procedure started with a skin incision of nearly 2 cm length. Muscle layers of the region were moved away through clockwise cannula rotation and the distancing of the tissues were followed by images produced by the flexible endoscope and played on the monitor. After the peritoneum perforation, the cavity exploration was started. After the ipsilateral side exploration to the access site, the transposing of the set cannula/endoscope was performed ventrally to the rear portion of the descending colon followed by the contralateral side exploration. When the examination was finished, the set was removed through counterclockwise cannula rotation and the skin incision was stitched to the subcutaneous. Moving the cannula among the abdominal organs was shown to be safe; however, spleen iatrogenic injury in two animals was highlighted by minor local hemorrhage. The majority of the abdominal structures described in the literature was possible to identify through the laparoscopic procedure in standing horses by single access. There was subcutaneous emphysema formation adjoining the surgical wounds in five of the six animals. The hematological parameters of the animals were kept in the limits established for the species, with exception of total leucocytes, segmented neutrophils and fibrinogen which showed small variations. The proposed approach was shown to be feasible and has the potential to make the procedure faster, more practical and safe and less invasive and expensive, fostering the diagnostic laparoscopy application in the equine species.

A técnica cirúrgica endoscópica transluminal por orifícios naturais (NOTES) tem por definição envolver a introdução de um endoscópio no interior da cavidade abdominal através de uma perfuração intencional de uma víscera (p.ex. estômago, reto, vagina) e realizar uma exploração e/ou operação intra-abdominal. A incisão cirúrgica realizada pela técnica de NOTES tem a vantagem de ser utilizada para a retirada da cavidade abdominal de espécimes (NOSE) reseccionadas através de uma laparoscopia padrão ou por NOTES. O presente estudo teve por objetivo verificar a viabilidade da cânula vaginal em realizar o acesso transvaginal para a cavidade abdominal através da técnica de NOTES transvaginal em éguas hígidas posicionadas em estação e avaliar o acesso vaginal como canal de extração de espécimes (NOSE) em éguas submetidas à ovariectomia laparoscópica via flanco. Foram utilizadas 6 éguas hígidas para ambos os procedimentos cirúrgicos. Os animais foram submetidos a jejum alimentar pré-cirúrgico de 24 à 30 horas. Para a sedação utilizou-se cloridrato de detomidina e cloridrato de lidocaína para execução da epidural baixa. A incisão vaginal foi realizada dorsal à cérvix na posição horária de 12 horas utilizando uma cânula vaginal de ponta romba rosqueada e realizada sob visualização indireta através do endoscópio flexível inserido dentro da cânula. A remoção dos ovários via vaginal ocorreu em quatro das seis éguas utilizadas no experimento. Das quatro éguas, três tiveram a necessidade do aumento manual da colpotomia para apreensão manual dos ovários intracavitária e sua remoção. Em dois animais os ovários tiveram de ser seccionados e removidos através do flanco pelo aumento da incisão do canal de trabalho laparoscópico. A execução cirúrgica do acesso à cavidade abdominal via transvaginal e a técnica de extração de espécimes por NOSE submetidas à ovariectomia laparoscópica via flanco é possível de ser realizada em éguas hígidas. / The technique of Natural Orifice Transluminal Endoscopic Surgery (NOTES), by definition, concerns the introduction of an endoscope in the abdominal cavity through an intentional perforation of a viscera (for ex., stomach, recto, vagina) and performs an intra-abdominal exploration and/or operation. The surgical incision performed through the NOTES technique has the benefit of being used to remove resected specimens (NOSE) from the abdominal cavity through a standard laparoscopy or through NOTES. The present study had the purpose to check the practicality of the vaginal cannula in performing transvaginal access to the abdominal cavity through the NOTES technique in standing healthy mares and assess the vaginal access as an canal extraction of specimens (NOSE) in mares subjected to laparoscopic ovariectomy. Six healthy mares were used for both surgical procedures. The food was withheld between 24 to 30 hours before surgery. They were sedated with detomidine hydrochloride and to perform the low epidural, lidocaine hydrochloride was used. The vaginal incision was performed dorsally to the cervix at 12 o’clock position using threaded round tip vaginal cannula and performed under indirect viewing through a flexible endoscope inserted in the cannula. The ovaries were removed through the vagina in four of the six mares used in the experiment. From the four mares, three were required to manually increase the colpotomy for manual intracavitary seizure of the ovaries and their removal. In two of the animals, the ovaries had to be cut and removed through the flank, increasing the incision of the laparoscopic working channel. The procedure to create the access to the abdominal cavity through the vagina to perform the NOTES technique and the specimen extraction technique through NOSE subjected to laparoscopic ovariectomy in healthy mares did not demonstrate high difficulties in its execution nor post-surgical complications, confirming the practicality of the two techniques in the equine species.

A laparoscopia é técnica cirúrgica minimamente invasiva na qual se utiliza um laparoscópio inserido por via transabdominal por onde é possível inspecionar visualmente a superfície das vísceras e do peritônio e realizar procedimentos cirúrgicos. Até o momento, a laparoscopia diagnóstica em equinos em estação através da fossa paralombar exige que sejam realizados dois procedimentos (um de cada lado do animal) para visualização significativa da cavidade peritoneal, além do uso de laparoscópio específico. Com o intuito de desenvolver a laparoscopia diagnóstica em equinos em estação por acesso único, foi desenvolvida uma cânula óptica com espiral sem trocarte de 60 cm de comprimento que tem o objetivo de promover maior segurança ao acesso laparoscópico (penetração radial sem trocarte e sob visualização) e sustentação ao endoscópio flexível para que seja possível realizar exploração significativa de ambos os hemisférios abdominais dorsais por apenas uma das fossas paralombares. Foram utilizados seis equinos adultos, sendo três machos e três fêmeas, submetidos a jejum alimentar de 24 a 30 horas. Amostras de sangue para realização de hemograma e dosagem de fibrinogênio foram obtidas no D-Pré, D4 e D7. Os equinos foram sedados com cloridrato de detomidina, seguido de bloqueio anestésico local com cloridrato de lidocaína infundida na musculatura e tecido subcutâneo do local de incisão no centro da fossa paralombar. O procedimento cirúrgico teve início com incisão cutânea de cerca de 2 cm de comprimento. As camadas musculares da região foram afastadas através da rotação da cânula em sentido horário e o afastamento dos tecidos foi acompanhado pelas imagens produzidas pelo endoscópio flexível e reproduzidas no monitor. Logo da perfuração do peritônio, foi iniciada a exploração da cavidade. Após a exploração do lado ipsilateral ao local de acesso, foi realizada a transposição do conjunto cânula/endoscópio ventralmente à porção caudal do cólon descendente seguida de exploração do lado contralateral. Terminado o exame, o conjunto foi removido através da rotação da cânula no sentido anti-horário e a incisão de pele foi suturada junto ao subcutâneo. A movimentação da cânula entre os órgãos abdominais mostrou-se segura, no entanto, em dois animais houve lesão iatrogênica ao baço, evidenciada por discreta hemorragia local. Foi possível a identificação da maioria das estruturas abdominais descritas na literatura por procedimento laparoscópico em equinos em estação pelo acesso único. Em cinco dos seis animais houve formação de enfisema subcutâneo adjacente às feridas cirúrgicas. Os parâmetros hematológicos dos animais mantiveram-se dentro dos limites estabelecidos para a espécie, com exceção dos leucócitos totais, neutrófilos segmentados e fibrinogênio que demonstraram pequenas variações. A abordagem proposta mostrou-se viável e tem o potencial de tornar o procedimento mais rápido, prático e seguro e menos invasivo e oneroso, fomentando a aplicação da laparoscopia diagnóstica na espécie equina. / Laparoscopy is a minimally invasive surgical technique by using a laparoscope inserted through the abdominal wall where it is visually possible to inspect visceral surfaces and peritoneum, and to perform surgical procedures. Up to now, diagnostic laparoscopy in standing horses through the paralumbar fossa requires two procedures to be performed (one on each side of the animal) in order to significantly see the peritoneal cavity, in addition of using specific laparoscope. With the purpose to develop a diagnostic laparoscopy in standing horses through a single access, a trocarless threaded visual cannula 60 cm length was designed with the aim to promote higher safety to laparoscopic access (radial penetration without trocar and under visualization), and support to a flexible endoscope so that a significant exploration of both dorsal abdominal hemispheres through only one of the paralumbar fossa is possible to perform. Six mature horses were used: three males and three females. Food was withheld for 24 to 30 hours before surgery. Blood samples to perform complete blood count and fibrinogen metering were obtained in D-Pre, D4, and D7. The horses were sedated with detomidine hydrochloride, followed by local anesthesia blockade with lidocaine hydrochloride infused in the muscle and subcutaneous tissue at the incision place in the center of the paralumbar fossa. The surgical procedure started with a skin incision of nearly 2 cm length. Muscle layers of the region were moved away through clockwise cannula rotation and the distancing of the tissues were followed by images produced by the flexible endoscope and played on the monitor. After the peritoneum perforation, the cavity exploration was started. After the ipsilateral side exploration to the access site, the transposing of the set cannula/endoscope was performed ventrally to the rear portion of the descending colon followed by the contralateral side exploration. When the examination was finished, the set was removed through counterclockwise cannula rotation and the skin incision was stitched to the subcutaneous. Moving the cannula among the abdominal organs was shown to be safe; however, spleen iatrogenic injury in two animals was highlighted by minor local hemorrhage. The majority of the abdominal structures described in the literature was possible to identify through the laparoscopic procedure in standing horses by single access. There was subcutaneous emphysema formation adjoining the surgical wounds in five of the six animals. The hematological parameters of the animals were kept in the limits established for the species, with exception of total leucocytes, segmented neutrophils and fibrinogen which showed small variations. The proposed approach was shown to be feasible and has the potential to make the procedure faster, more practical and safe and less invasive and expensive, fostering the diagnostic laparoscopy application in the equine species.

A técnica cirúrgica endoscópica transluminal por orifícios naturais (NOTES) tem por definição envolver a introdução de um endoscópio no interior da cavidade abdominal através de uma perfuração intencional de uma víscera (p.ex. estômago, reto, vagina) e realizar uma exploração e/ou operação intra-abdominal. A incisão cirúrgica realizada pela técnica de NOTES tem a vantagem de ser utilizada para a retirada da cavidade abdominal de espécimes (NOSE) reseccionadas através de uma laparoscopia padrão ou por NOTES. O presente estudo teve por objetivo verificar a viabilidade da cânula vaginal em realizar o acesso transvaginal para a cavidade abdominal através da técnica de NOTES transvaginal em éguas hígidas posicionadas em estação e avaliar o acesso vaginal como canal de extração de espécimes (NOSE) em éguas submetidas à ovariectomia laparoscópica via flanco. Foram utilizadas 6 éguas hígidas para ambos os procedimentos cirúrgicos. Os animais foram submetidos a jejum alimentar pré-cirúrgico de 24 à 30 horas. Para a sedação utilizou-se cloridrato de detomidina e cloridrato de lidocaína para execução da epidural baixa. A incisão vaginal foi realizada dorsal à cérvix na posição horária de 12 horas utilizando uma cânula vaginal de ponta romba rosqueada e realizada sob visualização indireta através do endoscópio flexível inserido dentro da cânula. A remoção dos ovários via vaginal ocorreu em quatro das seis éguas utilizadas no experimento. Das quatro éguas, três tiveram a necessidade do aumento manual da colpotomia para apreensão manual dos ovários intracavitária e sua remoção. Em dois animais os ovários tiveram de ser seccionados e removidos através do flanco pelo aumento da incisão do canal de trabalho laparoscópico. A execução cirúrgica do acesso à cavidade abdominal via transvaginal e a técnica de extração de espécimes por NOSE submetidas à ovariectomia laparoscópica via flanco é possível de ser realizada em éguas hígidas. / The technique of Natural Orifice Transluminal Endoscopic Surgery (NOTES), by definition, concerns the introduction of an endoscope in the abdominal cavity through an intentional perforation of a viscera (for ex., stomach, recto, vagina) and performs an intra-abdominal exploration and/or operation. The surgical incision performed through the NOTES technique has the benefit of being used to remove resected specimens (NOSE) from the abdominal cavity through a standard laparoscopy or through NOTES. The present study had the purpose to check the practicality of the vaginal cannula in performing transvaginal access to the abdominal cavity through the NOTES technique in standing healthy mares and assess the vaginal access as an canal extraction of specimens (NOSE) in mares subjected to laparoscopic ovariectomy. Six healthy mares were used for both surgical procedures. The food was withheld between 24 to 30 hours before surgery. They were sedated with detomidine hydrochloride and to perform the low epidural, lidocaine hydrochloride was used. The vaginal incision was performed dorsally to the cervix at 12 o’clock position using threaded round tip vaginal cannula and performed under indirect viewing through a flexible endoscope inserted in the cannula. The ovaries were removed through the vagina in four of the six mares used in the experiment. From the four mares, three were required to manually increase the colpotomy for manual intracavitary seizure of the ovaries and their removal. In two of the animals, the ovaries had to be cut and removed through the flank, increasing the incision of the laparoscopic working channel. The procedure to create the access to the abdominal cavity through the vagina to perform the NOTES technique and the specimen extraction technique through NOSE subjected to laparoscopic ovariectomy in healthy mares did not demonstrate high difficulties in its execution nor post-surgical complications, confirming the practicality of the two techniques in the equine species.

A laparoscopia é técnica cirúrgica minimamente invasiva na qual se utiliza um laparoscópio inserido por via transabdominal por onde é possível inspecionar visualmente a superfície das vísceras e do peritônio e realizar procedimentos cirúrgicos. Até o momento, a laparoscopia diagnóstica em equinos em estação através da fossa paralombar exige que sejam realizados dois procedimentos (um de cada lado do animal) para visualização significativa da cavidade peritoneal, além do uso de laparoscópio específico. Com o intuito de desenvolver a laparoscopia diagnóstica em equinos em estação por acesso único, foi desenvolvida uma cânula óptica com espiral sem trocarte de 60 cm de comprimento que tem o objetivo de promover maior segurança ao acesso laparoscópico (penetração radial sem trocarte e sob visualização) e sustentação ao endoscópio flexível para que seja possível realizar exploração significativa de ambos os hemisférios abdominais dorsais por apenas uma das fossas paralombares. Foram utilizados seis equinos adultos, sendo três machos e três fêmeas, submetidos a jejum alimentar de 24 a 30 horas. Amostras de sangue para realização de hemograma e dosagem de fibrinogênio foram obtidas no D-Pré, D4 e D7. Os equinos foram sedados com cloridrato de detomidina, seguido de bloqueio anestésico local com cloridrato de lidocaína infundida na musculatura e tecido subcutâneo do local de incisão no centro da fossa paralombar. O procedimento cirúrgico teve início com incisão cutânea de cerca de 2 cm de comprimento. As camadas musculares da região foram afastadas através da rotação da cânula em sentido horário e o afastamento dos tecidos foi acompanhado pelas imagens produzidas pelo endoscópio flexível e reproduzidas no monitor. Logo da perfuração do peritônio, foi iniciada a exploração da cavidade. Após a exploração do lado ipsilateral ao local de acesso, foi realizada a transposição do conjunto cânula/endoscópio ventralmente à porção caudal do cólon descendente seguida de exploração do lado contralateral. Terminado o exame, o conjunto foi removido através da rotação da cânula no sentido anti-horário e a incisão de pele foi suturada junto ao subcutâneo. A movimentação da cânula entre os órgãos abdominais mostrou-se segura, no entanto, em dois animais houve lesão iatrogênica ao baço, evidenciada por discreta hemorragia local. Foi possível a identificação da maioria das estruturas abdominais descritas na literatura por procedimento laparoscópico em equinos em estação pelo acesso único. Em cinco dos seis animais houve formação de enfisema subcutâneo adjacente às feridas cirúrgicas. Os parâmetros hematológicos dos animais mantiveram-se dentro dos limites estabelecidos para a espécie, com exceção dos leucócitos totais, neutrófilos segmentados e fibrinogênio que demonstraram pequenas variações. A abordagem proposta mostrou-se viável e tem o potencial de tornar o procedimento mais rápido, prático e seguro e menos invasivo e oneroso, fomentando a aplicação da laparoscopia diagnóstica na espécie equina. / Laparoscopy is a minimally invasive surgical technique by using a laparoscope inserted through the abdominal wall where it is visually possible to inspect visceral surfaces and peritoneum, and to perform surgical procedures. Up to now, diagnostic laparoscopy in standing horses through the paralumbar fossa requires two procedures to be performed (one on each side of the animal) in order to significantly see the peritoneal cavity, in addition of using specific laparoscope. With the purpose to develop a diagnostic laparoscopy in standing horses through a single access, a trocarless threaded visual cannula 60 cm length was designed with the aim to promote higher safety to laparoscopic access (radial penetration without trocar and under visualization), and support to a flexible endoscope so that a significant exploration of both dorsal abdominal hemispheres through only one of the paralumbar fossa is possible to perform. Six mature horses were used: three males and three females. Food was withheld for 24 to 30 hours before surgery. Blood samples to perform complete blood count and fibrinogen metering were obtained in D-Pre, D4, and D7. The horses were sedated with detomidine hydrochloride, followed by local anesthesia blockade with lidocaine hydrochloride infused in the muscle and subcutaneous tissue at the incision place in the center of the paralumbar fossa. The surgical procedure started with a skin incision of nearly 2 cm length. Muscle layers of the region were moved away through clockwise cannula rotation and the distancing of the tissues were followed by images produced by the flexible endoscope and played on the monitor. After the peritoneum perforation, the cavity exploration was started. After the ipsilateral side exploration to the access site, the transposing of the set cannula/endoscope was performed ventrally to the rear portion of the descending colon followed by the contralateral side exploration. When the examination was finished, the set was removed through counterclockwise cannula rotation and the skin incision was stitched to the subcutaneous. Moving the cannula among the abdominal organs was shown to be safe; however, spleen iatrogenic injury in two animals was highlighted by minor local hemorrhage. The majority of the abdominal structures described in the literature was possible to identify through the laparoscopic procedure in standing horses by single access. There was subcutaneous emphysema formation adjoining the surgical wounds in five of the six animals. The hematological parameters of the animals were kept in the limits established for the species, with exception of total leucocytes, segmented neutrophils and fibrinogen which showed small variations. The proposed approach was shown to be feasible and has the potential to make the procedure faster, more practical and safe and less invasive and expensive, fostering the diagnostic laparoscopy application in the equine species.

<div>In this thesis, the design of the robotic cannula for minimally invasive robotic lumbar discectomy is presented. Lumbar discectomy is the surgery to remove the herniated disc material that is pressing on a nerve root or spinal cord. </div><div><br></div><div>Recently, a robotic approach to performing this procedure has been proposed that utilizes multiple teleoperated articulated instruments inserted into the surgical workspace using a single cannula. In this paper, a new robotic cannula system to work in conjunction with this new procedure is presented. It allows for the independent teleoperated control of the axial position and rotation of up to three surgical instruments at the same time. The mechanical design, modeling, controller design, and the performance of the prototype of the new system are presented in this paper demonstrating a fully functioning device for this application. A novel worm gear and rack system allow for the instrument translation while and embedded gear trains produce the rotational movement. Steady-state errors of less than 10 microns for translation and less than 0.5 degree for rotation motion are achieved in position tracking; steady-state errors of less than 100 micron per second of translation and less than 0.5 degree per second for rotation motion are obtained in speed tracking. </div>

Nasal high flow (NHF) therapy is a recent form of non-invasive respiratory support for patients suffering from respiratory distress that supplies high flows of heated and humidified air, oxygen or a mix via a nasal cannula. A number of in vivo studies have proven its effectiveness at improving blood oxygenation; however, its mechanisms of action remain widely unproven. Two proposed mechanisms of action, the CO2 washout of anatomic dead space and the production of positive airway pressure, are investigated in this thesis for the use of the Fisher & Paykel Healthcare Ltd (FPH) Optiflow™ adult nasal cannula through a range of experiments. Five anatomically correct upper airway models produced from computed tomography (CT) scan data via 3D printing were employed during in vitro experiments and two live subjects participated in in vivo measurements. The human respiratory system was faithfully replicated for CO2 washout experiments with physiological CO2 diffusion into the lung replicated by a constant flow of CO2 into the lung pump. In vivo measurement of a natural breathing flow pattern was scaled to an average population tidal volume and respiratory rate for in vitro use. In vitro measurements of static pressure during natural breathing found similar flow resistances across the nasal passage for inspiratory and expiratory flow directions; however, across the entire upper airway greater resistance was seen for inspiration. Introduction of NHF therapy produced significant increases in all mean and peak airway pressures within the upper airway with a flow rate of 30 LPM fulfilling the inspiratory work requirements presented by the upper airway resistance. In vivo and in vitro hot wire anemometry measurements at the exterior nares indicated low velocity and turbulence intensity flows at peak inspiration and a high velocity jet with high turbulence during peak expiration. At natural breathing an in vitro anterior-posterior velopharynx traverse captured low turbulence intensities during peak inspiration and high turbulence intensities during peak expiration. Introduction of NHF therapy had little influence on the turbulence intensity profile of peak expiration yet did cause significant increases in the turbulence intensities during peak inspiration. Measurements of the CO2 concentration near the lung volume over many breath cycles were used to find time-averaged CO2 concentrations. For the standard airway model an average CO2 concentration of 4.88 ± 0.07 %V/V was determined during natural breathing. Implementation of increasing levels of NHF therapy generated significant washout of CO2 reducing this average concentration to a minimum of 3.81 ± 0.11 %V/V at a flow rate of 80 LPM. It was determined that airway geometry significantly affected the efficacy of the NHF therapy though CO2 washout was observed in all five airway models.

Ventricle Assist Devices (VADs), which are typically either axial or centrifugal flow pumps implanted on the aortic arch, have been used to support patients who are awaiting cardiac transplantation. Success of the apparatus in the short term has led to long term use. Despite anticoagulation measures, blood clots (thrombi) have been known to form in the device itself or inside of the heart. The Ventricle Assist Devices supply blood flow via a conduit (cannula) implanted on the ascending aorta. Currently, the implantation angle of the VAD cannula is not taken into consideration. Since the VADs supply a significant amount of blood flow to the aorta, the implantation angle can greatly affect the trajectory of the formed thrombi as well as the cardiac flow field inside of the aortic arch. This study aims to vary the implantation angle of a pediatric Left Ventricle Assist Device (LVAD) through a series of computational fluid dynamics (CFD) software simulations focusing on the aortic arch and its branching arteries of a 20 kg pediatric patient in order to reduce the occurrence of stroke.

Presented dissertation deals with the problematics of optimal choice of venous access for each hospitalized patient at standard internal wards. Introduction of vascular access must be safe for the patient and must allow the fulfillment of all the goals for which it was indicated. In recent years, in addition to peripheral cannulas and non-tunneled central catheters, introduction of midline catheters and PICC gets into everyday practice. The choice of optimal vascular access device since adminition can bring benefit to the patients in the form of decline of complications. Goal: The goal of master thesis was to prove that the use of new types of vascular access devices has influence on the decline of vascular access devices related complication occurence. Methods: To reach the goal we used a quantitative method of data collection during certain time period using created collection protocols. Research investigation took place from November 2017 to February 2018 at two standard wards of Department of Internal Medicine FN Motol. Results: A total of 350 venous access devices (271 peripheral cannulas, 54 midline catheters, 35 PICC) in 187 hospitalized patients was monitored. Prevalence of complications, average length of placement and reasons for extraction of individual vascular access devices was...

<p>UVOD: Anestezija je povezana sa promenama ventilacije, koje počinju sa prvim datim lekom, a mogu da traju i danima posle hirur&scaron;ke intervencije. Hipoksemija je najočiglednija posledica ove promene. U anesteziolo&scaron;koj praksi i perioperativnom tretmanu bolesnika kiseonička terapija zauzima značajno mesto. Jo&scaron; uvek ne postoje jasne, na dokazima zasnovane, smernice za upotrebu kiseoničke terapije u postoperativnom periodu. Razlog verovatno leži u činjenici da veliki broj faktora može da utiče na ishod lečenja hirur&scaron;kog bolesnika i zato je te&scaron;ko ispitati njihove pojedinačne uticaje. Kiseonička terapija tretira ili prevenira nastanak hipoksije obezbeđujući inspiratornu koncentraciju kiseonika veću od iste u vazduhu. Kod najvećeg broja pacijenata u postoperativnom periodu ne postoji potreba za strogom kontrolom inspiratorne koncentracije kiseonika, a administracija kiseoničke terapije sprovodi se primenom uređaja niskog protoka i varijabilne performanse, kao &scaron;to su nazalna kanila i kiseonička maska za lice. Brojna istraživanja poslednjih decenija poku&scaron;ala su da daju odgovor na pitanja da li postoji stvarna razlika u primeni ova dva uređaja, posebno u svetlu razvoja hipoksemije u postoperativnom periodu. Prednosti primene nazalne kanile su bolje prihvatanje od strane bolesnika u poređenju sa maskom, obično zbog manje izraženog osećaja klaustrofobije pri upotrebi nazalne kanile. Nazalna kanila, ne zahteva uklanjanje prilikom nege usne duplje ili per os unosa &scaron;to obezbeđuje kontinuitet u isporuci kiseonika. Nedostaci nazalne kanile vezani su za otežanu primenu kod bolesnika sa nazogastričnom sondom ili otežanim disanjem na nos. Pri protocima većim od 4 litre u mnuti može izazvati nelagodnost na nosnoj sluznici bolesnika. Literaturni podaci, ukazuju da se primenom kiseoničke maske ipak postižu veće inspiratorne koncentracije kiseonika, te da se epizode desaturacije i hipoksemije znatno ređe javljaju. Međutim, postoje i istraživanja koja ukazuju na mogućnost ponovnog udisanja vazduha iz mrtvog prostora maske, pri nižim protocima &scaron;to može uticati na parcijalni pritisak ugljen-dioksida u arterijskoj krvi. CILJEVI: Ciljevi istraživanja su da se ispitata učestalost javljanja hipoksemije unutar 48 sati od ekstubacije kod bolesnika u jedinici intezivne terapije, zatima da se ispita pojava desaturacije, da se utvrditi učestalost potrebe za primenom neinvazivne mehaničke ventilacije pozitivnim pritiskom kod bolesnika u jedinici intezivne terapije kod kojih se primenjuje kiseonička terapija putem nazalne kanile, odnosno kiseoničke maske. Takođe, cilj je i da se ispita da li postoji povezanost preoperativnih karakteristika bolesnika sa eventualnim izborom jednog od dva uređaja za primenu kiseoničke terapije u ranom postoperativnom periodu. METODOLOGIJA: Na Klinici za anesteziju i intenzivnu terapiju Kliničkog centra Vojvodine sprovedeno je prospektivno istraživanje kojim je obuhvaćeno 160 pacijenata nakon elektivnih hrur&scaron;kih procedura, koji su nakon operativnog zahvata praćeni u jedinici intenzivne terapije. Pacijenti su randomizovani u dve grupe (grupa M &ndash; kiseonička maska i grupa N &ndash; nazalna kanila) u odnosu na uređaj kojim je sprovođena postoperativna kiseonička terapija. Za sve pacijente uključene u studiju evidentirana je pol, starost, telesna masa, telesna visina, izračunat indeks telesne mase. Evidentiran je i ASA status, kao i NYHA status. U istraživanje nisu uključeni pacijenti sa plućnim komorbiditetima. Iz istraživanja su isključeni svi oni bolesnici kod kojih je do&scaron;lo do respiratornih komplikacija u perioperativnom periodu, kao i onih kod kojih je bila prisutna hemodinamska nestabilnost. Postoperativno svi pacijenti su sedirani, na mehaničkoj ventilaciji sme&scaron;teni u jedinicu intenzivne terapije. Nakon prevođenja na spontano disanje i ekstubacije započinjana je primena kiseonika putem kiseoničke maske za lice (6 l/min) odnosno nazalne kanile (4 l/min). Sprovođen je kontinuirani monitoring vitalnih parametara, saturacije hemoglobina kiseonikom, kao i novo ugljen-dioksida na kraju ekspirijuma. Kod svih pacijenata u četiri vremena rađene su gasne analize arterijske krvi. Svi praćeni parametri poređeni su između dve ispitivane grupe pacijenata. Za statističku obradu podataka kori&scaron;ćen je programski paket Statistical Package for Social Sciences - SPSS 21. Numerička obeležja su prikazana putem srednjih vrednosti (aritmetička sredina) i mera varijabiliteta (opseg vrednosti, standardna devijacija), a atributivna obeležja kori&scaron;ćenjem frekvencija i procenata. Komparacija vrednosti numeričkih obeležja između dve grupe vr&scaron;ena je primenom Studentovog t- testa, odnosno neparametrijskog Mann- Whitney testa. Testiranje razlike frekvencija atributivnih obeležja vr&scaron;eno je primenom &chi;2 testa. U cilju ispitivanja povezanosti dva ili vi&scaron;e obeležja, odnosno generisanja adekvatnih statističkih modela, kori&scaron;ćena je multivarijantna regresiona analiza. Statistički značajnim se smatraju vrednosti nivoa značajnosti p&lt;0.05. REZULTATI: U odnosu na preoperativne karakteristike ispitivanih pacijenata nije nađena statistički značajna razlika u distribuciji pacijenata u dve ispitivane grupe u odnosu na pol (2 test; 2=0,378;p=0,539), starost (T test; t=1,958; p=0,053), APACHE II skor na prijemu (Mann-Whitney test; U=1220,500; p=0,837), indeks telesne mase (T test; t=1,380; p=0,171), pu&scaron;ačkim navikama (2 test; 2=0,644;p=0,422), vrednostima preoperativnog hemoglobina (T test; t=0,442; p=0,660), saturacije hemoglobina kiseonikom (T test; t=0,883; p=0,380). Razlike nije bilo ni u pogledu trajanja mehaničke ventilacije (Mann-Whitney test; U=1114,500; p=0,345). Hipoksemija (parcijalni pritisak kiseonika u arterijskoj krvi manji od 65 mmHg) nije registrovana ni kod jednog od pacijenata u obe ispitivane grupe. Vrednsti SpO2 &lt; 92%, registrovane su kod ukupno 24 pacijenta u svim analiziranim vremenima (24%). Najveći broj pacijenata kod kojih je registrovana niska vrednost detektovan je u prvom satu nakon ekstubacije kada je vrednost manja od 92% registrovana kod 5 pacijenata (5%) i to kod 3 pacijenta u grupi M (6%) i 2 pacijenta u grupi N (4%). Između vizita 2. i 3. vrednosti satutracije manje od 92% registrovana je kod 19 pacijenata (19%), kod 8 pacijenata u grupi M (16%) i kod 11 pacijenata u grupi N (22%). U periodu između vizita 3. i 4. vrednosti saturacije niže od 92% registrovane su kod 19 (19%) pacijenata i to kod 10 pacijenata u grupi M (20%) i kod 9 pacijenata u grupi N (18%). Statistički značajna razlika zabeležena je u sve tri vizite (vizita 2, 3, 4) u vrednosti parcijalnog pritiska kiseonika u arterijskoj krvi. Tako su pacijenti u grupi kod kojih je primenjivana maska imali statistički značajno veće vrednosti parcijalnog pritiska kiseonika. Istovremeno pacijenti kod kojih je kiseonička terapija primenjivana putem maske imali su značajno veće vrednosti saturacije hemoglobina kiseonikom i ova razlika je bila statistički značajna u svim posmatranim vizitama. U prvih 48 sati nakon operacije neinvazivna mehanička ventilacija primenjena je kod 80 pacijenata. Kod svih pacijenata indikacija za primenu je bila pojava desaturacije. U odnosu na distribuciju pacijenata po ispitivanim grupama nije bilo statistički značajne razlike u broju pacijenata koji su zahtevali neinvazivnu mehaničku ventilaciju (2 test; 2=2,250; p=0,134). Pacijenti u grupi N proveli su vi&scaron;e minuta (srednja vrednost 56,85 +/- 19,80 minuta) na neinvazivnoj ventilaciji od pacijenata u grupi M (srednja vrednost 33,14 +/- 10,65 minuta), a ova razlika je statistički značajna (T test; t=2,923; p=0,009). Na osnovu multivarijantne regresione analize, pacijenti koji su kiseoničku terapiju primali putem nazalne kanile, sa porastom indeksa telesne mase imali su niže vrednosti parcijalnog pritiska kiseonika u arterijskoj krvi (r2=0,392). ZAKLJUČCI: Kiseonička maska za lice i nazalna kanila obezbeđuju adekvatnu primenu kiseoničke terapije u smislu prevencije nastanka hipoksemije u ranom postoperativnom periodu. Primenom kiseoničke maske za lice ostvaruju se vi&scaron;e vrednosti parcijalnog pritiska kiseonika u arterijskoj krvi. Epizode desaturacije če&scaron;će se javljaju kod pacijenata kod kojih se u ranom postoperativnom periodu primenjuje kiseonička terapija putem nazalne kanile. Pacijenti kod kojih se primenjuje kiseonička terapija putem maske ostvaruju veće vrednosti saturacije hemoglobina kiseonikom. Pacijenti kod kojih je kiseonička terapija u ranom postoperativnom periodu primenjivana putem nazalne kanile zahtevali su dužu primenu neinvazivne mehaničke ventilacije pluća. Kod pacijenata sa većim vrednostima indeksa telesne mase, za primenu kiseoničke terapije u ranom postoperativnom periodu, kiseonička maska za lice će obezbediti bolju oksigenaciju.</p> / <p>INTRODUCTION: Anesthesiology is associated with vicissitudes in ventilation, which start with application of first medicine and last for days following surgical intervention. Hypoxemia is a most common side effect of vicissitudes in ventilation. Oxygen therapy is important in anesthesiology and post-operative treatment of a patient. There are no clear evidence-based guidelines for application of oxygen therapy in post-operative period. Numerous factors influence patient&rsquo;s treatment outcome and it is difficult to examine each factor&rsquo;s independent impact. Oxygen therapy treats or prevents occurrence of hypoxemia by providing inspiratory concentration of oxygen greater than the amount found in air. Most patients in post-operative period don&rsquo;t require vigilant control of inspiratory concentration of oxygen, and administration of oxygen therapy is implemented with a low flow device with variable performances such as nasal cannula and oxygen face mask. Various research attempts where made in the last decades to discover an evident difference between these two devices, especially in cases where hypoxemia occurred in post-operative period. One advantage to using nasal cannula over oxygen face mask is that its better perceived by a patient as it reduces feeling of claustrophobia. Nasal cannula doesn&rsquo;t need to be removed during oral cavity care or &ldquo;per os&rdquo; intake which ensures continuous oxygen delivery. The drawback to using nasal cannula is that its challenging to insert it in a patient with nasogastric tube or difficult nasal breathing. Also, patient can experience nasal discomfort if the oxygen flow is bigger than four litters per minute. Literature data shows that application of oxygen trough the face mask achieves greater inspiratory concentrations of oxygen, and reduces the occurrence of desaturation and hypoxemia. Still, there is research which points out to the possibility of breathing in from dead space in the mask, in lower flows, which can partially affect pressure of carbon dioxide in artery blood. AIM: Aim of the research is to examine frequency of hypoxemia and non-invasive mechanical ventilation in patients treated with oxygen therapy via nasal cannula or oxygen face mask during the first 48 hours following patient extubating in intensive care unit. Also, aim is to examine correlation between patients&rsquo; pre-operative characteristics and the choice of one of the two devices for oxygen therapy in early postoperative period. METHODOLOGY: Clinic for Anesthesiology and Intensive Therapy at the Clinical Center of Vojvodina conducted this research on 160 patients who underwent elective surgical procedures and received post-operative care in Intensive Care Unit. Patients were randomly assigned to two groups (Group M with oxygen face mask and Group N with nasal cannula) relative to device which was used for post-operative oxygen therapy. Information recorded for all the patients included in the study constituted their gender, age, weight, hight, and body max index. ASA status, as well as NYHA status were also recorded. Research excluded any patient who experienced respiratory complications in post-operative period as well as those who experienced hemodynamic instability. Postoperatively all patients were sedated and on mechanical ventilation therapy in intensive care unit. After transition to spontaneous breathing and extubating, oxygen therapy was applied using oxygen mask (6 l/min) or nasal cannula (4 l/min). Vital parameters were continuously monitored as well as hemoglobin oxygen saturation, and carbon dioxide at the end of the expirium. Gas analysis of artery blood was carried out four times for all participants in the study. All parameters were compared between two examined patient groups. Statistical analysis was carried out using Statistical Package for Social Sciences - SPSS 21. Numerical features are depicted using arithmetic mean and variability rate, and attributive features are depicted with frequency and percentages. Comparison of the values of numerical characteristics between the two groups was performed using Student&#39;s t-test, that is, a non-parametric Mann-Whitney test. The frequency difference in attributive characteristics was tested using &chi;2 test. To generate adequate statistical model, multivariate regression analysis was applied to examine the link between two or more of features. Significant values are determined if level of significance is p&lt;0.05. RESULTS: Preoperative characteristics of the patient showed no significant differences between the two study groups. Characteristics were recorded with respect to gender (2 test; 2 = 0.378; p = 0.539), age (t-test; t = 1,958, p = 0,053 ), APACHE II score on admission (Mann-Whitney test; U = 1220.500; p = 0.837), body mass index (t-test; t = 1.380, p = 0.171), smoking habits (2 test; 2 = 0.644; p = 0.422), the values of the preoperative hemoglobin (t-test; t = 0.442, p = 0.660), and hemoglobin oxygen saturation (t-test; t = 0.883, p = 0.380). Difference was discovered in regards to duration of mechanical ventilation (Mann-Whitney test; U = 1114.500; p = 0.345). Hypoxemia (partial oxygen pressure in the arterial blood of less than 65 mmHg) was not registered in any of the patients in both study groups. Value SpO2&lt; 92%, was registered in 24 patients during every round (24%). Patients who registered value lower than 92% experienced it in the first hour post extubation. This was observed in 5 patients in total (5%) where 3 patients from group M (6%) and 2 from group N (4%). Between 2nd and 3rd rounds, saturation values lower than 92% were recorded in 19 patients (19%): 8 from group M (16%) and 11 from group N (22%). In the period between the 3rd and 4th rounds the value of saturation lower than 92% was detected in 19 (19%) patients: 10 from group M (20%) and 9 from group N (18%). Statistically significant difference was noted in all three rounds (rounds 2, 3, 4) in the values of the partial oxygen pressure in arterial blood. Thus, patients from the group treated with an oxygen face mask had significantly higher values of partial oxygen pressure. In addition patients treated by oxygen face mask had significantly higher levels of oxygen saturated hemoglobin, and this difference was statistically significant in all observed rounds. In the first 48 hours after surgery noninvasive mechanical ventilation was performed in 80 patients. Common indication for oxygen therapy in all patients was desaturation. There were no statistically significant differences in the number of patients who required non-invasive mechanical ventilation in either of the groups (2 test; 2 = 2.250; p = 0.134). Patients in group N received several minutes more (mean value of 56.85 +/- 19.80 minutes) of the non-invasive ventilation than patients in the group M (mean value of 33.14 +/- 10.65 minutes), and this difference was statistically significant (t-test; t = 2,923, p = 0,009). Based on the multivariate regression analysis, the patients who received oxygen therapy via nasal cannula, with the increase in body mass index had lower values of partial oxygen pressure in arterial blood (r2 = 0.392). CONCLUSION: Both face mask and nasal cannula ensure adequate application of oxygen therapy to prevent hypoxemia in the early postoperative period. Oxygen face mask achieves higher value of partial oxygen pressure in arterial blood. Episodes of desaturation more frequently occur in patients who receive oxygen therapy with nasal cannula in early postoperative period. Patients who receive oxygen therapy via oxygen face mask achieve higher hemoglobin oxygen saturation values. Patients who undergo oxygen therapy in the early postoperative period using nasal cannula require longer application of non-invasive mechanical ventilation. Patients with higher body mass index receive better oxygenation in the early postoperative period if facial mask is the device of choice.</p>