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Monitoring Central Venous Catheter Resistance to Predict Imminent Occlusion: A Prospective Pilot Study.

Wolf J, Tang L, Rubnitz JE, Brennan RC, Shook DR, Stokes DC, Monagle P, Curtis N, Worth LJ, Allison K, Sun Y, Flynn PM - PLoS ONE (2015)

Bottom Line: When turbulent flow through the device was evident, resistance was not estimated, and the result was noted as "non-laminar." Ten patients attended 113 catheter-resistance monitoring visits.Participants rated catheter-resistance monitoring as highly acceptable.Larger studies are required to validate these findings, assess the predictive value for other clinical outcomes, and determine the impact of pre-emptive therapy.

View Article: PubMed Central - PubMed

Affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America; Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America; Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia.

ABSTRACT

Background: Long-term central venous catheters are essential for the management of chronic medical conditions, including childhood cancer. Catheter occlusion is associated with an increased risk of subsequent complications, including bloodstream infection, venous thrombosis, and catheter fracture. Therefore, predicting and pre-emptively treating occlusions should prevent complications, but no method for predicting such occlusions has been developed.

Methods: We conducted a prospective trial to determine the feasibility, acceptability, and efficacy of catheter-resistance monitoring, a novel approach to predicting central venous catheter occlusion in pediatric patients. Participants who had tunneled catheters and were receiving treatment for cancer or undergoing hematopoietic stem cell transplantation underwent weekly catheter-resistance monitoring for up to 12 weeks. Resistance was assessed by measuring the inline pressure at multiple flow-rates via a syringe pump system fitted with a pressure-sensing transducer. When turbulent flow through the device was evident, resistance was not estimated, and the result was noted as "non-laminar."

Results: Ten patients attended 113 catheter-resistance monitoring visits. Elevated catheter resistance (>8.8% increase) was strongly associated with the subsequent development of acute catheter occlusion within 10 days (odds ratio = 6.2; 95% confidence interval, 1.8-21.5; p <0.01; sensitivity, 75%; specificity, 67%). A combined prediction model comprising either change in resistance greater than 8.8% or a non-laminar result predicted subsequent occlusion (odds ratio = 6.8; 95% confidence interval, 2.0-22.8; p = 0.002; sensitivity, 80%; specificity, 63%). Participants rated catheter-resistance monitoring as highly acceptable.

Conclusions: In this pediatric hematology and oncology population, catheter-resistance monitoring is feasible, acceptable, and predicts imminent catheter occlusion. Larger studies are required to validate these findings, assess the predictive value for other clinical outcomes, and determine the impact of pre-emptive therapy.

Trial registration: Clinicaltrials.gov NCT01737554.

No MeSH data available.


Related in: MedlinePlus

Estimation of catheter resistance.Resistance was calculated as the gradient of a pressure-flow plot. Results that were a poor fit to a least squares regression line (R2 <85%) were termed non-laminar, and resistance was not estimated.
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pone.0135904.g003: Estimation of catheter resistance.Resistance was calculated as the gradient of a pressure-flow plot. Results that were a poor fit to a least squares regression line (R2 <85%) were termed non-laminar, and resistance was not estimated.

Mentions: CRM was performed weekly by trained study staff (medical doctor or registered nurse) for up to 12 weeks, and participants were followed for clinical endpoints for 3 weeks after completion of the final CRM visit. During CRM visits, normal saline was infused through each lumen of the CVC at various predetermined flow rates while inline pressure was measured. Specifically, staff measured the inline pressure in the CVC twice at each of 4 flow rates (typically 10, 50, 100, and 150 mL/h). Pressure was measured using a syringe pump with an incorporated pressure-sensing transducer (Alaris 8110 Syringe Pump, CareFusion Inc., San Diego, CA). The pressure sensor was placed below the estimated height of the participant’s right atrium, with the participant lying at an angle of approximately 45°. The relative heights and positions of the patient and pump were not altered between or during measurements (Fig 2). Inline pressure was measured for 20 s during relaxed breathing at each flow rate, and the maximal pressure was recorded. Clinical staff and participants were blind to the CRM results. These data were used to produce a pressure-flow scatter plot (Fig 3), and the gradient of this plot was estimated by a least squares regression line. This gradient was then used to represent the resistance of that lumen. Because the least squares regression line was assumed to represent laminar flow, results that were a poor fit to this line (R2 <85%) were termed “non-laminar”, and resistance was not estimated.


Monitoring Central Venous Catheter Resistance to Predict Imminent Occlusion: A Prospective Pilot Study.

Wolf J, Tang L, Rubnitz JE, Brennan RC, Shook DR, Stokes DC, Monagle P, Curtis N, Worth LJ, Allison K, Sun Y, Flynn PM - PLoS ONE (2015)

Estimation of catheter resistance.Resistance was calculated as the gradient of a pressure-flow plot. Results that were a poor fit to a least squares regression line (R2 <85%) were termed non-laminar, and resistance was not estimated.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4555832&req=5

pone.0135904.g003: Estimation of catheter resistance.Resistance was calculated as the gradient of a pressure-flow plot. Results that were a poor fit to a least squares regression line (R2 <85%) were termed non-laminar, and resistance was not estimated.
Mentions: CRM was performed weekly by trained study staff (medical doctor or registered nurse) for up to 12 weeks, and participants were followed for clinical endpoints for 3 weeks after completion of the final CRM visit. During CRM visits, normal saline was infused through each lumen of the CVC at various predetermined flow rates while inline pressure was measured. Specifically, staff measured the inline pressure in the CVC twice at each of 4 flow rates (typically 10, 50, 100, and 150 mL/h). Pressure was measured using a syringe pump with an incorporated pressure-sensing transducer (Alaris 8110 Syringe Pump, CareFusion Inc., San Diego, CA). The pressure sensor was placed below the estimated height of the participant’s right atrium, with the participant lying at an angle of approximately 45°. The relative heights and positions of the patient and pump were not altered between or during measurements (Fig 2). Inline pressure was measured for 20 s during relaxed breathing at each flow rate, and the maximal pressure was recorded. Clinical staff and participants were blind to the CRM results. These data were used to produce a pressure-flow scatter plot (Fig 3), and the gradient of this plot was estimated by a least squares regression line. This gradient was then used to represent the resistance of that lumen. Because the least squares regression line was assumed to represent laminar flow, results that were a poor fit to this line (R2 <85%) were termed “non-laminar”, and resistance was not estimated.

Bottom Line: When turbulent flow through the device was evident, resistance was not estimated, and the result was noted as "non-laminar." Ten patients attended 113 catheter-resistance monitoring visits.Participants rated catheter-resistance monitoring as highly acceptable.Larger studies are required to validate these findings, assess the predictive value for other clinical outcomes, and determine the impact of pre-emptive therapy.

View Article: PubMed Central - PubMed

Affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America; Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America; Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia.

ABSTRACT

Background: Long-term central venous catheters are essential for the management of chronic medical conditions, including childhood cancer. Catheter occlusion is associated with an increased risk of subsequent complications, including bloodstream infection, venous thrombosis, and catheter fracture. Therefore, predicting and pre-emptively treating occlusions should prevent complications, but no method for predicting such occlusions has been developed.

Methods: We conducted a prospective trial to determine the feasibility, acceptability, and efficacy of catheter-resistance monitoring, a novel approach to predicting central venous catheter occlusion in pediatric patients. Participants who had tunneled catheters and were receiving treatment for cancer or undergoing hematopoietic stem cell transplantation underwent weekly catheter-resistance monitoring for up to 12 weeks. Resistance was assessed by measuring the inline pressure at multiple flow-rates via a syringe pump system fitted with a pressure-sensing transducer. When turbulent flow through the device was evident, resistance was not estimated, and the result was noted as "non-laminar."

Results: Ten patients attended 113 catheter-resistance monitoring visits. Elevated catheter resistance (>8.8% increase) was strongly associated with the subsequent development of acute catheter occlusion within 10 days (odds ratio = 6.2; 95% confidence interval, 1.8-21.5; p <0.01; sensitivity, 75%; specificity, 67%). A combined prediction model comprising either change in resistance greater than 8.8% or a non-laminar result predicted subsequent occlusion (odds ratio = 6.8; 95% confidence interval, 2.0-22.8; p = 0.002; sensitivity, 80%; specificity, 63%). Participants rated catheter-resistance monitoring as highly acceptable.

Conclusions: In this pediatric hematology and oncology population, catheter-resistance monitoring is feasible, acceptable, and predicts imminent catheter occlusion. Larger studies are required to validate these findings, assess the predictive value for other clinical outcomes, and determine the impact of pre-emptive therapy.

Trial registration: Clinicaltrials.gov NCT01737554.

No MeSH data available.


Related in: MedlinePlus