In this paper, the pulsatile flow of blood through an inclined catheterized stenosed artery is analyzed. Perturbation method is used to solve the implicit system of partial differential equations with suitable boundar...In this paper, the pulsatile flow of blood through an inclined catheterized stenosed artery is analyzed. Perturbation method is used to solve the implicit system of partial differential equations with suitable boundary conditions. Various analytical expressions axial velocity, flow rate, wall shear stress and effective viscosity have been derived with the help of MATLAB for understanding the fluid flow phenomena. The combined effect of catheterization, body acceleration, slip and inclination has been seen by plotting the graph and observed that axial velocity and flow rate increases with the increase in body acceleration, inclination angle and slip velocity while axial velocity diminishes on increasing the catheter radius. Wall shear stress increases with the increase in catheter radius and body acceleration but presence of slip velocity reduces the wall shear stress. Effective viscosity diminishes on increasing body acceleration and inclination angle, whereas slightly augmented in non-inclined stenosed artery.展开更多
The blood flow through a catheterized artery having a mild stenosis at the wall together with a blood clot at the centre is studied in the current investigation.Stenosis can occur in vessels carrying blood to brain(i....The blood flow through a catheterized artery having a mild stenosis at the wall together with a blood clot at the centre is studied in the current investigation.Stenosis can occur in vessels carrying blood to brain(i.e.,Carotid arteries),Renal arteries that supply blood to kidneys etc.The flow is refined in such vessels by application of catheter.We have used a Newtonian viscous fluid model and also distinct shapes of stenosis,(i.e.,symmetric and non-symmetric shapes)are considered for this study.The entropy generation togetherwith viscous dissipation is also taken into account for a complete description of heat transfer mechanism.Exact solutions are calculated for the problem subject to given“no slip conditions”.The results are discussed graphically.The velocity quickly increases for a non-symmetric stenosis as compared to a symmetric stenosis.When the height of mild stenosis increases and the channel becomes narrow then the velocity increases in the centre but it decreases with the stenosed wall.However,as the height of blood clotσincreases then the velocity of blood flow reduces with the wall having clot but it remains almost same with the stenosed wall.Streamlines are plotted to visualize the flow pattern.The trapping is symmetric for a symmetric stenosis shape but it changes to non-symmetric trapping when we have a non-symmetric shape of stenosis.展开更多
A mathematical model for pulsatile flow of blood in a catheterized artery in presence of an axisymmetric stenosis with a velocity slip at the constricted wall is proposed. The expressions for the flow characteristics,...A mathematical model for pulsatile flow of blood in a catheterized artery in presence of an axisymmetric stenosis with a velocity slip at the constricted wall is proposed. The expressions for the flow characteristics, velocity profiles, the flow resistance, the wall shear stress, the effective viscosity are obtained in the present analysis. The effects of slip velocity on the blood flow characteristics are shown graphically and discussed briefly.展开更多
<strong>Introduction: </strong>Urinary tract infection represents more than 40% of all nosocomial infections of which 80% are attributed to the use of an indwelling urinary catheter. Although the device is...<strong>Introduction: </strong>Urinary tract infection represents more than 40% of all nosocomial infections of which 80% are attributed to the use of an indwelling urinary catheter. Although the device is useful medically to treat urinary retention and incontinence, its uses have also been associated with infections such as catheter-associated urinary tract infections. <strong>Objectives:</strong> To evaluate catheter-associated urinary tract infection in terms of its prevalence, pathogens causing the infection and the resistance pattern to some commonly used antibiotics. <strong>Methods: </strong>Urine and biofilm specimen were collected from 105 catheterized patients. Bacteria pathogens were identified based on colony morphology, Gram staining and other biochemical reactions. Kirby-Bauer disc diffusion method was employed to determine the antibiotic resistance pattern of the isolated pathogens. <strong>Results: </strong>The study recorded a 74.29% prevalence of catheter-associated urinary tract infection among the rarely symptomatic patients. <em>Escherichia coli</em> were significantly isolated (p < 0.000) in both samples compared to Klebsiella pneumoniae and <em>Staphylococcus aureus</em>. Most isolated pathogens from both samples were resistant to ciprofloxacin with the biofilm pathogens being highly resistant than the urine pathogens. K. pneumoniae from both samples showed higher resistance levels to antibiotics than <em>E. coli</em> and <em>S. aureus</em>. <strong>Conclusion:</strong> Ciprofloxacin, a commonly used antibiotic by catheterized patients turn out to be less effective against the pathogens. The use of ciprofloxacin in catheter-associated urinary tract infection treatment should therefore be given a second thought.展开更多
Catheter is commonly used by the surgeons for various reasons in the treatment of a patient suffering with cardiovascular diseases. Catheterization increases the mean flow resistance in the arterial blood flow and man...Catheter is commonly used by the surgeons for various reasons in the treatment of a patient suffering with cardiovascular diseases. Catheterization increases the mean flow resistance in the arterial blood flow and many other complications are associated with the presence of catheter in the artery. Effects of catheter in stenosed artery can be estimated non-invasively by means of hemo-dynamic indicator-WSS, WSSG, volume flow rate and impedance. The effect of slip at the arterial wall, inclination of the artery and magnetic field on the hemodynamic indicators and flow profiles are computed, presented and discussed through graphs.展开更多
Staphylococcus lentus(S.lentus)is a coagulase negative gram positive cocci recognized as opportunistic pathogens and rarely forming biofilm;it has many virulence factors,but recently caused nosocomial and community in...Staphylococcus lentus(S.lentus)is a coagulase negative gram positive cocci recognized as opportunistic pathogens and rarely forming biofilm;it has many virulence factors,but recently caused nosocomial and community infections.Biofilm formation of Staphylococcus lentus may be associated with the ability to resist antibiotics which leads to increase in mortality rate due to the difficulty in eradicate infections.To evaluate the biofilm forming capacity of Staphylococcus lentus and its susceptibility to antibiotics,phenotypic and genotypic assays were used.Among 28 biofilm bacteria,Staphylococcus lentus was isolated and identified from urine catheterized patients who were hospitalized in different departments of four Iraqi hospitals(Al-Diwaniyah Teaching,Al-Hilla Teaching,Al Qassim and Al Hashimiyah Hospitals).Staphylococcus lentus was examined for detection of biofilm formation by detecting icaA gene,the intercellular adhesion gene which expressed adhesion factor to form biofilm in staphylococci by using polymerase chain reaction(PCR)method and tested for antimicrobial susceptibility by disc diffusion method and VITEK2 system according to guidelines of the Clinical&Laboratory Standards Institute(CLSI).Three isolates of Staphylococcus lentus revealed the ability to form biofilm phenotypically which contained icaA gene with 100%antibiotics resistance to penicillin,carbenicillin,gentamicin,tobramycin,oxacillin,vancomycin,clindamycin,ciprofloxacin,and 0%antibiotics resistance to azithromycin.icaA genes are present in Staphylococcus lentus and responsible for biofilm formation which is considered as the indicator;biofilm formation is a strong cause of multidrug resistance in bacteria.展开更多
A perturbation analysis based on equations of motion in Lagrangian form is presented for the oscillatory and time-mean viscous flows induced by a propagating wave of small amplitude in an annulus with a viscoelastic o...A perturbation analysis based on equations of motion in Lagrangian form is presented for the oscillatory and time-mean viscous flows induced by a propagating wave of small amplitude in an annulus with a viscoelastic outer wall. Owing to the steady streaming effect, the existence of a catheter in a blood vessel brings in an additional steady pressure gradient, a correction to that predicted by the linear theory, and an additional steady shear stress, which may increase the possibility of hemolysis of red blood cells.展开更多
Serratia fonticola and Pantoea sp.are gram negative bacteria belonging Enterobactericeae,which were considered opportunistic pathogens and resulted in a great number of cases of nosocomial infections with serious prob...Serratia fonticola and Pantoea sp.are gram negative bacteria belonging Enterobactericeae,which were considered opportunistic pathogens and resulted in a great number of cases of nosocomial infections with serious problems of multi-drug resistance,leading to increasing morbidity and mortality rate.Recently,they were recorded as biofilm producers.There were only a few studies about the capability of these bacteria of forming biofilm.So our aim was evaluate the occurrence of Serratia fonticola and Pantoea sp.biofilm former phenotypically and genetically with the determination of their abilities to multi-drug resistance.Serratia fonticola and Pantoea sp.isolated from urine catheterized patients who were hospitalized in Iraqi hospitals.They were then examined for detection of biofilm formation phenotypically by congo red and tissue culture plate methods and genetically by detecting SmaI and EsaI genes(quarm sensing genes)in Serratia fonticola and Pantoea sp.respectively by using polymerase chain reaction method and tested for antimicrobial susceptibility by disc diffusion and VITEK2 system according to Clinical and Laboratory Standards Institute(CLSI).Serratia fonticola at 3 and Pantoea sp.at 4 isolates revealed to possess the ability of forming biofilm which contained SmaI and EsaI genes with 100%resistance to most tested antibiotics except imipenem and azithromycin.SmaI and EsaI genes are present in Serratia fonticola and Pantoea sp.respectively,and are responsible for biofilm formation and considered as indicator;biofilm formation is a strong cause of multidrug resistance in bacteria.展开更多
In this paper, the flow of blood through catheterized artery with mild constriction at the outer wall is considered. The closed form solutions are obtained for velocity and microrotation components. The impedance （re...In this paper, the flow of blood through catheterized artery with mild constriction at the outer wall is considered. The closed form solutions are obtained for velocity and microrotation components. The impedance （resistance to the flow） and wall shear stress are calculated. The effects of catheterization, coupling number, micropolar parameter, and height of the stenosis on impedance and wall shear stresses are discussed.展开更多
BACKGROUND Long-term chemotherapy for patients with gastric cancer(GC),facilitated by peripherally inserted central catheter(PICC)catheterization,reduces vascular damage and enhances drug delivery efficiency but carri...BACKGROUND Long-term chemotherapy for patients with gastric cancer(GC),facilitated by peripherally inserted central catheter(PICC)catheterization,reduces vascular damage and enhances drug delivery efficiency but carries risks of catheter-related complications.A combination of group psychological nursing and physical mo-vement care significantly mitigates the risk of venous thrombosis and improves psychological well-being,and enhances motor function,underscoring its clinical importance.AIM To assess group psychological and physical movement nursing in preventing venous thrombosis in patients with PICC GC.METHODS Sixty-five GC patients with PICC,admitted from January 2022 to January 2023,were randomly divided into two groups using the lottery method:A control group(n=35,routine nursing)and an observation group(n=30,routine nursing plus psychological nursing and physical movement nursing).Both groups re-ceived continuous care for 2 weeks.Pre-nursing and post-nursing data on psycho-logical state,physical function,chemotherapy-related thrombosis incidence,and cancer-related fatigue were analyzed using SPSS 26.0 and GraphPad Prism 8.0.RESULTS After nursing,both groups showed reduced Hamilton Anxiety Scale scores and increased General Perceived Self-Efficacy Scale scores,with the observation group performing better(P<0.05).The Functional Comprehensive Assessment score for the observation group after nursing was(65.42±2.35)points,lower than the control group’s(62.19±4.33)points(P<0.05).Although no significant difference was observed in the incidence of venous thrombosis between the two groups(χ2=0.815,P=0.367),the observation group had lower incidence.Both groups showed decreased Revised Piper Fatigue Scale scores,with the observation group scoring lower(P<0.05).CONCLUSION Group psychological and physical movement nursing for patients with PICC reduces venous thrombosis risk,improves psychological well-being,cancer-related fatigue,and physical function,making it highly promotable.展开更多
BACKGROUND Urologists are commonly consulted regarding difficult and traumatic urethral catheterizations.Complications surrounding Foley catheterizations represent a significant burden to the healthcare system.AIM To ...BACKGROUND Urologists are commonly consulted regarding difficult and traumatic urethral catheterizations.Complications surrounding Foley catheterizations represent a significant burden to the healthcare system.AIM To assess the demographic and patient characteristics surrounding urological consultation for difficult and traumatic Foley catheterizations at our institution across multiple hospitals.METHODS This is a single-institution,multi-hospital,263 patient,retrospective chart review from Jan 2020–December 2023.RESULTS The majority of consultations(80.2%)did not require heroic measures by the urology service.A Foley catheter placement was determined not difficult in the majority 191(72.6%)of patients.Sub-group analysis of“difficult by urology”vs“not difficult by urology”,showed a significant difference between those with zero attempts,one attempt,and greater than one attempts(P=0.004).Those patients specifically with greater than one attempts were more likely to be seen as a difficult insertion by urology assessment(60.6%)compared to not difficult(38.6%).Likewise,those patients with a history of difficult urethral catheter(DUC)/traumatic urethral catheterization(TUC)(25.8%)were more likely to be difficult compared to those without a history of DUC/TUC(14.2%)(P=0.038).CONCLUSION The study found that majority of consultations received did not require heroic measures by the urology service to place a catheter.Patients who had a history of DUC/TUC and those who had greater than one catheter attempts were statistically more likely to be a DUC based on urology assessment.At our institution we hope to propose a protocol in which nursing staff and non-urologic clinicians will utilize a troubleshooting checklist and an algorithm when difficult or traumatic urethral catheters are encountered in order to improve patient care and decrease healthcare costs.For example,this protocol would ideally address complications of multiple catheter attempts such as urethral trauma,development of urethral strictures,and infection risk.Additionally,future trainings and availability of additional resources will be provided and assessed with a goal of reducing healthcare cost surrounding these complications.展开更多
Urethral catheterization is an important skill to develop as consultations for“difficult catheterization”are common in practice.Developing a broad approach to difficult urethral catheterization is crucial to improve...Urethral catheterization is an important skill to develop as consultations for“difficult catheterization”are common in practice.Developing a broad approach to difficult urethral catheterization is crucial to improve trainee success rates.Strategies and techniques to improve catheterization success are often passed down and shared between trainees without formal documentation or dissemination of techniques.Herein,we present a framework for difficult urethral catheterization based on clinical history and patient examination,while also providing additional techniques and troubleshooting to overcome common challenges with urethral catheterization in adult and pediatric patients.展开更多
Background:The choice of a basket or a balloon catheter during endoscopic retrograde cholangiopancreatography(ERCP)for the clearance of pancreatic duct stones in patients with chronic pancreatitis(CP)remains controver...Background:The choice of a basket or a balloon catheter during endoscopic retrograde cholangiopancreatography(ERCP)for the clearance of pancreatic duct stones in patients with chronic pancreatitis(CP)remains controversial.This study compared the efficacy and safety of these two devices for pancreatic duct stone extractions.Methods:We compared the efficacy and safety of basket and balloon catheters for pancreatic stone extractions.We enrolled CP patients who underwent ERCP for the first time at Changhai Hospital,Naval Medical University between February 2012 and December 2021.After propensity score matching(1:1),101 patients were included in each group.The primary outcome was the rate of pancreatic stone clearance.Secondary outcomes included the rate of adverse events during hospitalization,long-term pain relief,and quality of life after one year follow-up period.Results:The rate of complete clearance was comparable between the two groups(86.1%vs.84.2%,P=0.692).In patients with stones≥2 cm before extracorporeal shock wave lithotripsy(ESWL),the rate of complete clearance was significantly higher in the balloon catheter group when compared to the basket catheter group[100%(19/19)vs.70.0%(14/20),P=0.031].In the multivariate logistic analysis,ESWL prior to stone extraction was the only independent predictor of complete clearance[with ESWL 58.4%(264/452)vs.without ESWL 41.6%(188/452),odds ratio=2.3,95%confidence interval:1.2–4.3;P=0.013].No significant differences between groups were found regarding the rates of adverse events during hospitalization,quality of life,and pain relief after one year of follow-up.Conclusions:Basket and balloon catheters showed similar efficacy and safety for pancreatic stone extractions.However,the balloon catheter was superior to the basket catheter if the pancreatic stone size was≥2 cm before ESWL.展开更多
BACKGROUND Peripherally inserted central catheters(PICCs)are crucial for patients requiring long-term intravenous therapy,especially within digestive surgery under bundled care protocols.AIM To evaluate and compare th...BACKGROUND Peripherally inserted central catheters(PICCs)are crucial for patients requiring long-term intravenous therapy,especially within digestive surgery under bundled care protocols.AIM To evaluate and compare the efficacy,safety,and patient-reported outcomes of single-lumen vs double-lumen PICCs among patients undergoing digestive surgery within a structured bundled care framework.METHODS This retrospective cohort study analyzed data from 249 patients who underwent digestive surgery and utilized either single-lumen(n=117)or double-lumen(n=132)PICCs between January 2021 and June 2024.Clinical outcomes,patient satisfaction,catheterization duration,and complication rates were compared using statistical analysis via SPSS(version 29.0).The bundled care protocol was consistently applied,focusing on standardized procedures,staff training,and patient support.RESULTS Single-lumen PICCs were associated with a significantly lower thrombosis rate(0.85%)than double-lumen PICCs(6.82%,P=0.039).The single-lumen group experienced shorter catheterization durations(12.5±3.14 days vs 13.6±4.50 days,P=0.025)and higher successful infusion rates(92.7%±5.32%vs 90.4%±6.60%,P=0.003).This group also reported higher comfort scores(8.40±1.20 vs 7.90±1.50,P=0.004)and lower pain levels(2.90±0.70 vs 3.20±0.80,P=0.002).Aside from thrombosis,complication rates showed no significant difference between the groups.CONCLUSION Within bundled care context,single-lumen PICCs demonstrated advantages in reducing thrombosis risk,procedural efficiency,patient comfort,and satisfaction compared with double-lumen PICCs.The findings underscore the importance of considering patient-specific needs and clinical scenarios in catheter choice.展开更多
Persistent left superior vena cava(PLSVC)is a congenital anomaly where the left-sided vena cava,which usually regresses during fetal development,persists.Double superior vena cava resulting from a PLSVC is indeed a ra...Persistent left superior vena cava(PLSVC)is a congenital anomaly where the left-sided vena cava,which usually regresses during fetal development,persists.Double superior vena cava resulting from a PLSVC is indeed a rare phenomenon.In the general population,the incidence of this condition is reported to be between 0.3%and 2.1%.[1]While this anatomical variation is often asymptomatic and discovered incidentally,it becomes relevant in certain clinical scenarios.Indeed,the presence of a PLSVC and double superior vena cava can pose challenges as incorrect positioning and result in failure.展开更多
BACKGROUND Few studies have quantified invasive hemodynamic parameters in post heart transplant recipients.AIM To report the incidence of abnormal hemodynamics in heart transplant recipients at 1-year and 3-year post-...BACKGROUND Few studies have quantified invasive hemodynamic parameters in post heart transplant recipients.AIM To report the incidence of abnormal hemodynamics in heart transplant recipients at 1-year and 3-year post-transplant and determine if there was any correlation with recipient and donor characteristics.METHODS Data from 279 consecutive heart transplant recipients from 2007 through 2020 were analyzed.Clinical variables regarding both recipients and donors as well as hemodynamic variables obtained via right heart catheterization during 1-year and 3-year annual testing were recorded.Simple and multiple linear regression tests were used to determine how recipient and donor variables influenced hemodynamic parameters at 1-year and 3-year.RESULTS Data were available for 260 patients and 224 patients at 1-year and 3-year posttransplant respectively.At 1-year,abnormal hemodynamic parameters were common with 24%patients having right atrial pressure(RAP)>10 mmHg,52%with mean pulmonary artery pressure>20 mmHg,and 12%with pulmonary capillary wedge pressure(PCWP)>18 mmHg.Similar abnormalities were noted at 3-year post-transplant.Recipient body mass index(BMI)demonstrated the strongest correlation with all 3 variables at both 1-year and 3-year by multivariate linear regression analysis(P<0.001 for both).Both donor age and predicted heart mass difference between recipient and donor were significantly linked to RAP and PCWP at 1-year but did not predict any variables at 3-year post-transplant.CONCLUSION Abnormal hemodynamics are common at 1-year and 3-year post-transplant and are associated with recipients with high BMI.展开更多
BACKGROUND Endoscopic retrograde cholangiopancreatography is a challenging procedure involving bile duct cannulation.Despite the development of several cannulation devices,none have effectively facilitated the procedu...BACKGROUND Endoscopic retrograde cholangiopancreatography is a challenging procedure involving bile duct cannulation.Despite the development of several cannulation devices,none have effectively facilitated the procedure.AIM To evaluate the efficacy of a recently developed catheter for bile duct cannulation.METHODS We retrospectively examined 342 patients who underwent initial cholangiopan-creatography.We compared the success rate of bile duct cannulation and the incidence of complications between the groups using existing and novel catheters.RESULTS The overall success rates of bile duct cannulation were 98.3%and 99.1%in the existing and novel catheter groups,respectively(P=0.47).The bile duct cannulation rate using the standard technique was 73.0%and 82.1%in the existing and novel catheter groups,respectively(P=0.042).Furthermore,when catheterization was performed by expert physicians,the bile duct cannulation rate was significantly higher in the novel catheter group(81.3%)than in the existing catheter group(65.2%)(P=0.017).The incidence of difficult cannulation was also significantly lower in the novel catheter group(17.4%)than in the existing catheter group(33.0%)(P=0.019).CONCLUSION The novel catheter improved the bile duct cannulation rate using the standard technique and reduced the frequency of difficult cannulation cases,valuable tool in endoscopic retrograde cholangiopancreatography procedures performed by experts.展开更多
Objective:To evaluate the impact of subcutaneous tunneling on peripherally inserted central catheters(PICCs)dislodgement and malposition.Dislodged or malpositioned PICCs can lead to improper treatment.The subcutaneous...Objective:To evaluate the impact of subcutaneous tunneling on peripherally inserted central catheters(PICCs)dislodgement and malposition.Dislodged or malpositioned PICCs can lead to improper treatment.The subcutaneous tunneling strategy may be effective,but there is insufficient evidence,and proximal movement has not been explored.Methods:We randomized 630 patients who needed PICCs placement to either the tunneled PICCs(experimental group)or the non-tunneled PICCs(control group).Dislodgement and malposition of the catheter were the primary outcomes,and catheter-related infection(CRI)and catheter-related thrombosis(CRT)were the secondary outcomes.Results:Subcutaneous tunneling does not significantly reduce distal catheter movement,but it significantly reduces proximal catheter movement(4.3%vs.9.9%,P=0.007),which may explain the lower incidence of CRI(2.0%vs.5.3%,P=0.030)and CRT(3.6%vs.12.5%,P<0.001).Conclusions:Although subcutaneous tunneling does not significantly improve catheter prolapse,it should still be used clinically because proximal catheter movement can be a more serious problem associated with CRI and CRT.展开更多
BACKGROUND Percutaneous nephrolithotomy(PNL)is the standard treatment for medium-sized and large kidney stones.Many potential complications of PNL may warrant hospital readmission(HR)after discharge,threatening patien...BACKGROUND Percutaneous nephrolithotomy(PNL)is the standard treatment for medium-sized and large kidney stones.Many potential complications of PNL may warrant hospital readmission(HR)after discharge,threatening patient safety and increasing the costs.AIM To estimate the rate of unplanned HR after PNL and identify its urological and nursing-related predictors.METHODS One hundred sixty-one patients were prospectively studied for HR after PNL from April 2022 to December 2022.The relevant urological and nursing-related characteristics of patients with and without unplanned HR after PNL were studied for association with HR,using univariate and multivariate analyses.Variables such as the demographic characteristics,comorbidities,laboratory and imaging characteristics,dietary status,operative time,number of kidney punctures,blood loss,urinary tract infections,and the receipt of instructions for catheter care and activities of daily living were included.A risk score was created.RESULTS The mean age of patients with HR(44.4±12.7 years)and without HR(43.9±12.6 years)was similar(P=0.847).The overall stone-free rate was 88.8%.The total complication rate was 32.3%(52 patients),and the highest grade was IIIa,according to the modified Clavein grading system,resulting in an HR rate of 22.4%.History of preoperative pyuria(P=0.001),hydronephrosis(P=0.001)and mean stone size(P=0.012),multiple renal punctures(P<0.001),double J stent(P=0.033),total operative time(P=0.001),intraoperative injury(P=0.011),postoperative urinary tract infection(P<0.001),and inadequate instructions for urethral catheter(P=0.001)and activity daily living(P=0.048)were significantly associated with HR after PNL.On multivariate analysis,only preoperative pyuria(P=0.004),intraoperative injury(P=0.001),and inadequate instructions on urethral catheter care(P=0.035)were associated with HR.The risk score of the independent predictors was 0-17;0-4(low risk),5-9(moderate risk),and 10-17(high risk).CONCLUSION The rate of unplanned HR after PNL was relatively high(22.4%).The presence of pus cells in the preoperative urine analysis,intraoperative injury,and receiving inadequate instructions on urethral catheter care were independent predictors of HR after PNL.Combined studying of the urological and nursing-related predictors may promote the implementation of enhanced recovery protocols after PNL.展开更多
文摘In this paper, the pulsatile flow of blood through an inclined catheterized stenosed artery is analyzed. Perturbation method is used to solve the implicit system of partial differential equations with suitable boundary conditions. Various analytical expressions axial velocity, flow rate, wall shear stress and effective viscosity have been derived with the help of MATLAB for understanding the fluid flow phenomena. The combined effect of catheterization, body acceleration, slip and inclination has been seen by plotting the graph and observed that axial velocity and flow rate increases with the increase in body acceleration, inclination angle and slip velocity while axial velocity diminishes on increasing the catheter radius. Wall shear stress increases with the increase in catheter radius and body acceleration but presence of slip velocity reduces the wall shear stress. Effective viscosity diminishes on increasing body acceleration and inclination angle, whereas slightly augmented in non-inclined stenosed artery.
文摘The blood flow through a catheterized artery having a mild stenosis at the wall together with a blood clot at the centre is studied in the current investigation.Stenosis can occur in vessels carrying blood to brain(i.e.,Carotid arteries),Renal arteries that supply blood to kidneys etc.The flow is refined in such vessels by application of catheter.We have used a Newtonian viscous fluid model and also distinct shapes of stenosis,(i.e.,symmetric and non-symmetric shapes)are considered for this study.The entropy generation togetherwith viscous dissipation is also taken into account for a complete description of heat transfer mechanism.Exact solutions are calculated for the problem subject to given“no slip conditions”.The results are discussed graphically.The velocity quickly increases for a non-symmetric stenosis as compared to a symmetric stenosis.When the height of mild stenosis increases and the channel becomes narrow then the velocity increases in the centre but it decreases with the stenosed wall.However,as the height of blood clotσincreases then the velocity of blood flow reduces with the wall having clot but it remains almost same with the stenosed wall.Streamlines are plotted to visualize the flow pattern.The trapping is symmetric for a symmetric stenosis shape but it changes to non-symmetric trapping when we have a non-symmetric shape of stenosis.
文摘A mathematical model for pulsatile flow of blood in a catheterized artery in presence of an axisymmetric stenosis with a velocity slip at the constricted wall is proposed. The expressions for the flow characteristics, velocity profiles, the flow resistance, the wall shear stress, the effective viscosity are obtained in the present analysis. The effects of slip velocity on the blood flow characteristics are shown graphically and discussed briefly.
文摘<strong>Introduction: </strong>Urinary tract infection represents more than 40% of all nosocomial infections of which 80% are attributed to the use of an indwelling urinary catheter. Although the device is useful medically to treat urinary retention and incontinence, its uses have also been associated with infections such as catheter-associated urinary tract infections. <strong>Objectives:</strong> To evaluate catheter-associated urinary tract infection in terms of its prevalence, pathogens causing the infection and the resistance pattern to some commonly used antibiotics. <strong>Methods: </strong>Urine and biofilm specimen were collected from 105 catheterized patients. Bacteria pathogens were identified based on colony morphology, Gram staining and other biochemical reactions. Kirby-Bauer disc diffusion method was employed to determine the antibiotic resistance pattern of the isolated pathogens. <strong>Results: </strong>The study recorded a 74.29% prevalence of catheter-associated urinary tract infection among the rarely symptomatic patients. <em>Escherichia coli</em> were significantly isolated (p < 0.000) in both samples compared to Klebsiella pneumoniae and <em>Staphylococcus aureus</em>. Most isolated pathogens from both samples were resistant to ciprofloxacin with the biofilm pathogens being highly resistant than the urine pathogens. K. pneumoniae from both samples showed higher resistance levels to antibiotics than <em>E. coli</em> and <em>S. aureus</em>. <strong>Conclusion:</strong> Ciprofloxacin, a commonly used antibiotic by catheterized patients turn out to be less effective against the pathogens. The use of ciprofloxacin in catheter-associated urinary tract infection treatment should therefore be given a second thought.
文摘Catheter is commonly used by the surgeons for various reasons in the treatment of a patient suffering with cardiovascular diseases. Catheterization increases the mean flow resistance in the arterial blood flow and many other complications are associated with the presence of catheter in the artery. Effects of catheter in stenosed artery can be estimated non-invasively by means of hemo-dynamic indicator-WSS, WSSG, volume flow rate and impedance. The effect of slip at the arterial wall, inclination of the artery and magnetic field on the hemodynamic indicators and flow profiles are computed, presented and discussed through graphs.
文摘Staphylococcus lentus(S.lentus)is a coagulase negative gram positive cocci recognized as opportunistic pathogens and rarely forming biofilm;it has many virulence factors,but recently caused nosocomial and community infections.Biofilm formation of Staphylococcus lentus may be associated with the ability to resist antibiotics which leads to increase in mortality rate due to the difficulty in eradicate infections.To evaluate the biofilm forming capacity of Staphylococcus lentus and its susceptibility to antibiotics,phenotypic and genotypic assays were used.Among 28 biofilm bacteria,Staphylococcus lentus was isolated and identified from urine catheterized patients who were hospitalized in different departments of four Iraqi hospitals(Al-Diwaniyah Teaching,Al-Hilla Teaching,Al Qassim and Al Hashimiyah Hospitals).Staphylococcus lentus was examined for detection of biofilm formation by detecting icaA gene,the intercellular adhesion gene which expressed adhesion factor to form biofilm in staphylococci by using polymerase chain reaction(PCR)method and tested for antimicrobial susceptibility by disc diffusion method and VITEK2 system according to guidelines of the Clinical&Laboratory Standards Institute(CLSI).Three isolates of Staphylococcus lentus revealed the ability to form biofilm phenotypically which contained icaA gene with 100%antibiotics resistance to penicillin,carbenicillin,gentamicin,tobramycin,oxacillin,vancomycin,clindamycin,ciprofloxacin,and 0%antibiotics resistance to azithromycin.icaA genes are present in Staphylococcus lentus and responsible for biofilm formation which is considered as the indicator;biofilm formation is a strong cause of multidrug resistance in bacteria.
基金Project supported by the Research Grants Council of the Hong Kong Special Administrative Region, China (Grant No. HKU 715609E)
文摘A perturbation analysis based on equations of motion in Lagrangian form is presented for the oscillatory and time-mean viscous flows induced by a propagating wave of small amplitude in an annulus with a viscoelastic outer wall. Owing to the steady streaming effect, the existence of a catheter in a blood vessel brings in an additional steady pressure gradient, a correction to that predicted by the linear theory, and an additional steady shear stress, which may increase the possibility of hemolysis of red blood cells.
文摘Serratia fonticola and Pantoea sp.are gram negative bacteria belonging Enterobactericeae,which were considered opportunistic pathogens and resulted in a great number of cases of nosocomial infections with serious problems of multi-drug resistance,leading to increasing morbidity and mortality rate.Recently,they were recorded as biofilm producers.There were only a few studies about the capability of these bacteria of forming biofilm.So our aim was evaluate the occurrence of Serratia fonticola and Pantoea sp.biofilm former phenotypically and genetically with the determination of their abilities to multi-drug resistance.Serratia fonticola and Pantoea sp.isolated from urine catheterized patients who were hospitalized in Iraqi hospitals.They were then examined for detection of biofilm formation phenotypically by congo red and tissue culture plate methods and genetically by detecting SmaI and EsaI genes(quarm sensing genes)in Serratia fonticola and Pantoea sp.respectively by using polymerase chain reaction method and tested for antimicrobial susceptibility by disc diffusion and VITEK2 system according to Clinical and Laboratory Standards Institute(CLSI).Serratia fonticola at 3 and Pantoea sp.at 4 isolates revealed to possess the ability of forming biofilm which contained SmaI and EsaI genes with 100%resistance to most tested antibiotics except imipenem and azithromycin.SmaI and EsaI genes are present in Serratia fonticola and Pantoea sp.respectively,and are responsible for biofilm formation and considered as indicator;biofilm formation is a strong cause of multidrug resistance in bacteria.
文摘In this paper, the flow of blood through catheterized artery with mild constriction at the outer wall is considered. The closed form solutions are obtained for velocity and microrotation components. The impedance （resistance to the flow） and wall shear stress are calculated. The effects of catheterization, coupling number, micropolar parameter, and height of the stenosis on impedance and wall shear stresses are discussed.
文摘BACKGROUND Long-term chemotherapy for patients with gastric cancer(GC),facilitated by peripherally inserted central catheter(PICC)catheterization,reduces vascular damage and enhances drug delivery efficiency but carries risks of catheter-related complications.A combination of group psychological nursing and physical mo-vement care significantly mitigates the risk of venous thrombosis and improves psychological well-being,and enhances motor function,underscoring its clinical importance.AIM To assess group psychological and physical movement nursing in preventing venous thrombosis in patients with PICC GC.METHODS Sixty-five GC patients with PICC,admitted from January 2022 to January 2023,were randomly divided into two groups using the lottery method:A control group(n=35,routine nursing)and an observation group(n=30,routine nursing plus psychological nursing and physical movement nursing).Both groups re-ceived continuous care for 2 weeks.Pre-nursing and post-nursing data on psycho-logical state,physical function,chemotherapy-related thrombosis incidence,and cancer-related fatigue were analyzed using SPSS 26.0 and GraphPad Prism 8.0.RESULTS After nursing,both groups showed reduced Hamilton Anxiety Scale scores and increased General Perceived Self-Efficacy Scale scores,with the observation group performing better(P<0.05).The Functional Comprehensive Assessment score for the observation group after nursing was(65.42±2.35)points,lower than the control group’s(62.19±4.33)points(P<0.05).Although no significant difference was observed in the incidence of venous thrombosis between the two groups(χ2=0.815,P=0.367),the observation group had lower incidence.Both groups showed decreased Revised Piper Fatigue Scale scores,with the observation group scoring lower(P<0.05).CONCLUSION Group psychological and physical movement nursing for patients with PICC reduces venous thrombosis risk,improves psychological well-being,cancer-related fatigue,and physical function,making it highly promotable.
文摘BACKGROUND Urologists are commonly consulted regarding difficult and traumatic urethral catheterizations.Complications surrounding Foley catheterizations represent a significant burden to the healthcare system.AIM To assess the demographic and patient characteristics surrounding urological consultation for difficult and traumatic Foley catheterizations at our institution across multiple hospitals.METHODS This is a single-institution,multi-hospital,263 patient,retrospective chart review from Jan 2020–December 2023.RESULTS The majority of consultations(80.2%)did not require heroic measures by the urology service.A Foley catheter placement was determined not difficult in the majority 191(72.6%)of patients.Sub-group analysis of“difficult by urology”vs“not difficult by urology”,showed a significant difference between those with zero attempts,one attempt,and greater than one attempts(P=0.004).Those patients specifically with greater than one attempts were more likely to be seen as a difficult insertion by urology assessment(60.6%)compared to not difficult(38.6%).Likewise,those patients with a history of difficult urethral catheter(DUC)/traumatic urethral catheterization(TUC)(25.8%)were more likely to be difficult compared to those without a history of DUC/TUC(14.2%)(P=0.038).CONCLUSION The study found that majority of consultations received did not require heroic measures by the urology service to place a catheter.Patients who had a history of DUC/TUC and those who had greater than one catheter attempts were statistically more likely to be a DUC based on urology assessment.At our institution we hope to propose a protocol in which nursing staff and non-urologic clinicians will utilize a troubleshooting checklist and an algorithm when difficult or traumatic urethral catheters are encountered in order to improve patient care and decrease healthcare costs.For example,this protocol would ideally address complications of multiple catheter attempts such as urethral trauma,development of urethral strictures,and infection risk.Additionally,future trainings and availability of additional resources will be provided and assessed with a goal of reducing healthcare cost surrounding these complications.
文摘Urethral catheterization is an important skill to develop as consultations for“difficult catheterization”are common in practice.Developing a broad approach to difficult urethral catheterization is crucial to improve trainee success rates.Strategies and techniques to improve catheterization success are often passed down and shared between trainees without formal documentation or dissemination of techniques.Herein,we present a framework for difficult urethral catheterization based on clinical history and patient examination,while also providing additional techniques and troubleshooting to overcome common challenges with urethral catheterization in adult and pediatric patients.
基金supported by grants from the National Nat-ural Science Foundation of China(82222012 and 82120108006)Scientific Innovation Program of Shanghai Municipal Education Committee(201901070007E00052)。
文摘Background:The choice of a basket or a balloon catheter during endoscopic retrograde cholangiopancreatography(ERCP)for the clearance of pancreatic duct stones in patients with chronic pancreatitis(CP)remains controversial.This study compared the efficacy and safety of these two devices for pancreatic duct stone extractions.Methods:We compared the efficacy and safety of basket and balloon catheters for pancreatic stone extractions.We enrolled CP patients who underwent ERCP for the first time at Changhai Hospital,Naval Medical University between February 2012 and December 2021.After propensity score matching(1:1),101 patients were included in each group.The primary outcome was the rate of pancreatic stone clearance.Secondary outcomes included the rate of adverse events during hospitalization,long-term pain relief,and quality of life after one year follow-up period.Results:The rate of complete clearance was comparable between the two groups(86.1%vs.84.2%,P=0.692).In patients with stones≥2 cm before extracorporeal shock wave lithotripsy(ESWL),the rate of complete clearance was significantly higher in the balloon catheter group when compared to the basket catheter group[100%(19/19)vs.70.0%(14/20),P=0.031].In the multivariate logistic analysis,ESWL prior to stone extraction was the only independent predictor of complete clearance[with ESWL 58.4%(264/452)vs.without ESWL 41.6%(188/452),odds ratio=2.3,95%confidence interval:1.2–4.3;P=0.013].No significant differences between groups were found regarding the rates of adverse events during hospitalization,quality of life,and pain relief after one year of follow-up.Conclusions:Basket and balloon catheters showed similar efficacy and safety for pancreatic stone extractions.However,the balloon catheter was superior to the basket catheter if the pancreatic stone size was≥2 cm before ESWL.
文摘BACKGROUND Peripherally inserted central catheters(PICCs)are crucial for patients requiring long-term intravenous therapy,especially within digestive surgery under bundled care protocols.AIM To evaluate and compare the efficacy,safety,and patient-reported outcomes of single-lumen vs double-lumen PICCs among patients undergoing digestive surgery within a structured bundled care framework.METHODS This retrospective cohort study analyzed data from 249 patients who underwent digestive surgery and utilized either single-lumen(n=117)or double-lumen(n=132)PICCs between January 2021 and June 2024.Clinical outcomes,patient satisfaction,catheterization duration,and complication rates were compared using statistical analysis via SPSS(version 29.0).The bundled care protocol was consistently applied,focusing on standardized procedures,staff training,and patient support.RESULTS Single-lumen PICCs were associated with a significantly lower thrombosis rate(0.85%)than double-lumen PICCs(6.82%,P=0.039).The single-lumen group experienced shorter catheterization durations(12.5±3.14 days vs 13.6±4.50 days,P=0.025)and higher successful infusion rates(92.7%±5.32%vs 90.4%±6.60%,P=0.003).This group also reported higher comfort scores(8.40±1.20 vs 7.90±1.50,P=0.004)and lower pain levels(2.90±0.70 vs 3.20±0.80,P=0.002).Aside from thrombosis,complication rates showed no significant difference between the groups.CONCLUSION Within bundled care context,single-lumen PICCs demonstrated advantages in reducing thrombosis risk,procedural efficiency,patient comfort,and satisfaction compared with double-lumen PICCs.The findings underscore the importance of considering patient-specific needs and clinical scenarios in catheter choice.
文摘Persistent left superior vena cava(PLSVC)is a congenital anomaly where the left-sided vena cava,which usually regresses during fetal development,persists.Double superior vena cava resulting from a PLSVC is indeed a rare phenomenon.In the general population,the incidence of this condition is reported to be between 0.3%and 2.1%.[1]While this anatomical variation is often asymptomatic and discovered incidentally,it becomes relevant in certain clinical scenarios.Indeed,the presence of a PLSVC and double superior vena cava can pose challenges as incorrect positioning and result in failure.
文摘BACKGROUND Few studies have quantified invasive hemodynamic parameters in post heart transplant recipients.AIM To report the incidence of abnormal hemodynamics in heart transplant recipients at 1-year and 3-year post-transplant and determine if there was any correlation with recipient and donor characteristics.METHODS Data from 279 consecutive heart transplant recipients from 2007 through 2020 were analyzed.Clinical variables regarding both recipients and donors as well as hemodynamic variables obtained via right heart catheterization during 1-year and 3-year annual testing were recorded.Simple and multiple linear regression tests were used to determine how recipient and donor variables influenced hemodynamic parameters at 1-year and 3-year.RESULTS Data were available for 260 patients and 224 patients at 1-year and 3-year posttransplant respectively.At 1-year,abnormal hemodynamic parameters were common with 24%patients having right atrial pressure(RAP)>10 mmHg,52%with mean pulmonary artery pressure>20 mmHg,and 12%with pulmonary capillary wedge pressure(PCWP)>18 mmHg.Similar abnormalities were noted at 3-year post-transplant.Recipient body mass index(BMI)demonstrated the strongest correlation with all 3 variables at both 1-year and 3-year by multivariate linear regression analysis(P<0.001 for both).Both donor age and predicted heart mass difference between recipient and donor were significantly linked to RAP and PCWP at 1-year but did not predict any variables at 3-year post-transplant.CONCLUSION Abnormal hemodynamics are common at 1-year and 3-year post-transplant and are associated with recipients with high BMI.
文摘BACKGROUND Endoscopic retrograde cholangiopancreatography is a challenging procedure involving bile duct cannulation.Despite the development of several cannulation devices,none have effectively facilitated the procedure.AIM To evaluate the efficacy of a recently developed catheter for bile duct cannulation.METHODS We retrospectively examined 342 patients who underwent initial cholangiopan-creatography.We compared the success rate of bile duct cannulation and the incidence of complications between the groups using existing and novel catheters.RESULTS The overall success rates of bile duct cannulation were 98.3%and 99.1%in the existing and novel catheter groups,respectively(P=0.47).The bile duct cannulation rate using the standard technique was 73.0%and 82.1%in the existing and novel catheter groups,respectively(P=0.042).Furthermore,when catheterization was performed by expert physicians,the bile duct cannulation rate was significantly higher in the novel catheter group(81.3%)than in the existing catheter group(65.2%)(P=0.017).The incidence of difficult cannulation was also significantly lower in the novel catheter group(17.4%)than in the existing catheter group(33.0%)(P=0.019).CONCLUSION The novel catheter improved the bile duct cannulation rate using the standard technique and reduced the frequency of difficult cannulation cases,valuable tool in endoscopic retrograde cholangiopancreatography procedures performed by experts.
文摘Objective:To evaluate the impact of subcutaneous tunneling on peripherally inserted central catheters(PICCs)dislodgement and malposition.Dislodged or malpositioned PICCs can lead to improper treatment.The subcutaneous tunneling strategy may be effective,but there is insufficient evidence,and proximal movement has not been explored.Methods:We randomized 630 patients who needed PICCs placement to either the tunneled PICCs(experimental group)or the non-tunneled PICCs(control group).Dislodgement and malposition of the catheter were the primary outcomes,and catheter-related infection(CRI)and catheter-related thrombosis(CRT)were the secondary outcomes.Results:Subcutaneous tunneling does not significantly reduce distal catheter movement,but it significantly reduces proximal catheter movement(4.3%vs.9.9%,P=0.007),which may explain the lower incidence of CRI(2.0%vs.5.3%,P=0.030)and CRT(3.6%vs.12.5%,P<0.001).Conclusions:Although subcutaneous tunneling does not significantly improve catheter prolapse,it should still be used clinically because proximal catheter movement can be a more serious problem associated with CRI and CRT.
文摘BACKGROUND Percutaneous nephrolithotomy(PNL)is the standard treatment for medium-sized and large kidney stones.Many potential complications of PNL may warrant hospital readmission(HR)after discharge,threatening patient safety and increasing the costs.AIM To estimate the rate of unplanned HR after PNL and identify its urological and nursing-related predictors.METHODS One hundred sixty-one patients were prospectively studied for HR after PNL from April 2022 to December 2022.The relevant urological and nursing-related characteristics of patients with and without unplanned HR after PNL were studied for association with HR,using univariate and multivariate analyses.Variables such as the demographic characteristics,comorbidities,laboratory and imaging characteristics,dietary status,operative time,number of kidney punctures,blood loss,urinary tract infections,and the receipt of instructions for catheter care and activities of daily living were included.A risk score was created.RESULTS The mean age of patients with HR(44.4±12.7 years)and without HR(43.9±12.6 years)was similar(P=0.847).The overall stone-free rate was 88.8%.The total complication rate was 32.3%(52 patients),and the highest grade was IIIa,according to the modified Clavein grading system,resulting in an HR rate of 22.4%.History of preoperative pyuria(P=0.001),hydronephrosis(P=0.001)and mean stone size(P=0.012),multiple renal punctures(P<0.001),double J stent(P=0.033),total operative time(P=0.001),intraoperative injury(P=0.011),postoperative urinary tract infection(P<0.001),and inadequate instructions for urethral catheter(P=0.001)and activity daily living(P=0.048)were significantly associated with HR after PNL.On multivariate analysis,only preoperative pyuria(P=0.004),intraoperative injury(P=0.001),and inadequate instructions on urethral catheter care(P=0.035)were associated with HR.The risk score of the independent predictors was 0-17;0-4(low risk),5-9(moderate risk),and 10-17(high risk).CONCLUSION The rate of unplanned HR after PNL was relatively high(22.4%).The presence of pus cells in the preoperative urine analysis,intraoperative injury,and receiving inadequate instructions on urethral catheter care were independent predictors of HR after PNL.Combined studying of the urological and nursing-related predictors may promote the implementation of enhanced recovery protocols after PNL.
