Biomedical subjects

Brian R Jacobs

Publications and source records attributed to Brian R Jacobs.

24 records · Page 2Linked to original sources

PubMed2002

Capillary and arterial blood gases in hemorrhagic shock: a comparative study.

OBJECTIVES: To determine whether capillary blood gas samples accurately reflect the information obtained from arterial blood gas samples in a porcine hemorrhagic shock model. DESIGN: Randomized prospective study. SETTING: Animal research laboratory at a children's hospital. SUBJECTS: Fifteen adult Yorkshire pigs. INTERVENTIONS: Tracheally intubated, ventilated, and anesthetized pigs were randomly assigned to either a control group (n = 10) or a hemorrhagic shock group (n = 5). After instrumentation, the hemorrhagic shock group underwent a 40-mL/kg hemorrhage over 2 hrs, while the control group did not. Animals were then monitored over a 3-hr period. MEASUREMENTS AND MAIN RESULTS: Simultaneous arterial blood gas and capillary blood gas samples were obtained from each animal by using standardized technique. Capillary blood gas pH accurately predicted arterial blood gas pH in both control and hemorrhagic shock groups (r = .94, p < .01, and r = .78, p < .01, respectively). Bland-Altman analysis revealed a mean difference between arterial blood gas pH and capillary blood gas pH of 0.016 (95% limit of agreement, +/-0.037) in the control group vs. a mean difference between arterial blood gas pH and capillary blood gas pH of 0.075 (95% limit of agreement, +/-0.142) in the hemorrhagic shock group. Capillary blood gas Pco2 accurately predicted arterial blood gas Pco2 in the control group but not in the hemorrhagic shock group (r = .80, p < .01, and r = .13, p = .41, respectively). By Bland-Altman analysis, the mean difference between arterial blood gas Pco2 and capillary blood gas Pco2 was 3.9, with a 95% limit of agreement of +/-3.61 in the control group. In the hemorrhagic shock group, the mean difference between arterial blood gas Pco2 and capillary blood gas Pco2 was 11.7 with a 95% limit of agreement of +/-38.8. Hemorrhagic shock group capillary blood gas samples significantly overestimated Pco2 (Delta = 11.7, p < .01) and underestimated pH (Delta = 0.075, p < .01) compared with arterial blood gas samples. CONCLUSIONS: Capillary blood gas samples are poor predictors of Pco2 and pH in porcine hemorrhagic shock. These findings should be taken into account when capillary blood gas samples are used in the monitoring and management of subjects diagnosed with shock.

Journal Article↗

PubMedDate not supplied

The efficacy and safety of blood sampling through peripherally inserted central catheter devices in children.

BACKGROUND: The peripherally inserted central catheter (PICC) is commonly used in children for medication and fluid administration. In addition, PICCs are used occasionally for blood sampling as an alternative to venipuncture. Blood sampling from these catheters carries the hypothetical risk of catheter occlusion caused by blood remaining in the catheter, and this practice is not supported by PICC manufacturers. Children often undergo multiple needle punctures, which are associated with pain, anxiety, and dissatisfaction with care. The authors hypothesized that blood sampling through 3-Fr PICC devices is effective and safe for children. METHODS: After placement of a 3-Fr PICC, all the children were sequentially enrolled in one of two groups. The control group included patients that had 3-Fr PICC devices without blood sampling. The blood sampling group included patients with 3-Fr PICC devices through which blood samples were obtained. Demographic data, PICC placement and sampling data, infusate composition, catheter occlusion, mechanical complications, and blood stream infections were recorded. The primary outcome variable was the difference in occlusion rates between the two groups. RESULTS: The analysis included 204 children with 3-Fr PICCs (120 in the blood sampling group and 84 in the control group) who had a mean age, 117.7 +/- 4.9 months. The mean PICC duration was 15.6 +/- 1.0 days. Blood sampling was successful more than 98% of the time from all blood sampling group catheters, with a mean of 4.4 +/- 0.5 samples removed from each catheter. There was a higher occlusion rate in the blood sampling group. However, this result did not reach statistical significance. There were no significant differences between the groups in terms of infection or mechanical complication rates. CONCLUSIONS: Blood sampling is feasible and effective through 3-Fr PICC devices in children. This practice is not associated with a significant increase in occlusion, infection, or mechanical complication rates.

Age Factors↗

PubMedDate not supplied

Peripherally inserted central catheters in children: a survey of practice patterns.

There is little published information describing standards of practice in the placement, use, and maintenance of peripherally inserted central catheter (PICC) devices in children. A Web-based survey tool was designed to query these issues, and 72 intravenous therapy nurses from 72 hospitals provided complete responses to the survey. The respondents were predominantly (81%) from healthcare organizations inserting 40 or fewer PICC devices per month. These hospitals were equally divided in using 0.9% sodium chloride (USP) (saline) or heparinized saline flush to maintain patency, whereas 76% used catheters for blood sampling. Flushing and blood sampling practices were not related to catheter occlusion rates. From their survey, the authors conclude that the standards of practice for 3-Fr PICC devices, the most commonly used for children, are quite variable and in need of standardization for this specific population.

Adolescent↗

PubMedDate not supplied

Continuation of transpyloric feeding during weaning of mechanical ventilation and tracheal extubation in children: a randomized controlled trial.

BACKGROUND: Nutrition support is essential in the management of critically ill children. There is no current literature to support the common practice of discontinuing enteral nutrition delivered through a transpyloric feeding tube during the tracheal extubation process. We conducted a prospective, randomized controlled trial in mechanically ventilated children to examine the safety and efficacy of continuous transpyloric feeding compared with interrupted transpyloric feeding at the time of tracheal extubation. METHODS: Subjects were randomly assigned to receive transpyloric feeding throughout the tracheal extubation process (Continuous Group) or to have transpyloric feeding discontinued 4 hours before tracheal extubation and restarted 4 hours after tracheal extubation (Interrupted Group). Data consisting of patient demographics, admission pediatric risk of mortality (PRISM) score, diagnoses, adverse events (feeding intolerance, gastroesophageal reflux, and pulmonary aspiration), daily feeding volume, and caloric intake were recorded for the 3 days surrounding tracheal extubation. RESULTS: Fifty-nine patients completed the study (29 in Continuous Group, 30 in Interrupted Group). There was no episode of pulmonary aspiration in either group. The Continuous Group experienced 4 adverse events, whereas the Interrupted Group experienced 3 adverse events (p = not significant). The Continuous Group received 92 +/- 2.5% of their caloric goal on the day of weaning from the ventilator (day 1) and 93 +/- 3.2% on the day of tracheal extubation (day 2) compared with 76 +/- 4.2% and 43 +/- 4.3%, respectively, in the Interrupted Group (p < .004 and p < .0001, respectively). CONCLUSIONS: Continuous transpyloric feeding during weaning from the ventilator and tracheal extubation is safe and results in the delivery of more optimal nutrition.

Critical Illness↗

PubMedDate not supplied

Central venous catheter occlusion: a prospective, controlled trial examining the impact of a positive-pressure valve device.

BACKGROUND: Central venous catheter (CVC) occlusion occurs frequently in children. This problem is often associated with disruption of intravascular therapy and monitoring. Multiple factors may predispose to catheter occlusion, but reflux of blood into the catheter lumen is a common factor. We hypothesized that use of a positive pressure valve device would reduce the incidence of catheter occlusion. METHODS: In phase I of this sequential study design, newly placed CVCs were capped with a standard device. In Phase II, CVCs were capped with a positive-pressure valve device. Data collected included patient demographics, type of catheter, infusate, catheter duration, and complications. Partial and complete catheter occlusions were delineated. A user satisfaction survey was conducted. RESULTS: There were 153 children (mean age 48.0 +/- 7.7 months) with 312 CVC lumens enrolled in the study. Mean catheter duration was 9.4 +/- 0.9 days. There were fewer complete occlusions in CVCs capped with the positive pressure valve device than with the standard device [6/161 (3.7%) vs 18/151 (11.9%) occlusions, respectively; p = .012)]. There were no significant differences in partial occlusions, phlebitis, or catheter-related bloodstream infection between the 2 groups. CONCLUSIONS: CVCs with a positive-pressure valve cap device have a lower incidence of complete catheter occlusion than those with a standard cap device.

Catheterization, Central Venous↗

PubMedDate not supplied

The impact of needleless connector device design on central venous catheter occlusion in children: a prospective, controlled trial.

BACKGROUND: Intraluminal occlusion is common in children with central venous catheters (CVCs). Although multiple factors predispose CVCs to occlusion, reflux of blood is frequently implicated. We hypothesized that use of either a single-valve or positive-pressure-valve needleless connector device would reduce CVC occlusion rates in comparison to a standard device. We further hypothesized that saline would be as effective as heparinized saline flush in preventing occlusion and infection. METHODS: CVC lumens were prospectively capped with 1 of 3 needleless connector devices in a 4-group design. Group 1 lumens were capped with a standard device, group 2 with a single-valve device, group 3 with a positive-pressure-valve device flushed with heparinized saline, and group 4 with a positive-pressure-valve device flushed with saline. Data were obtained regarding occlusion and infection rates and user satisfaction. RESULTS: Three hundred sixty children with 599 CVC lumens completed the study. Complete occlusion occurred in 19/150 (12.7%) lumens in group 1 in comparison to 2/150 (1.3%) in group 2, 5/149 (3.4%) in group 3, and 6/150 (4%) in group 4 (p < .05). There was a trend toward a 2-fold greater infection rate in group 4. User satisfaction was higher in groups 2, 3, and 4 than group 1 (p < .05). CONCLUSIONS: CVCs capped with a single-valve or positive-pressure-valve needleless connector device have lower complete catheter occlusion rates than those capped with a standard device. Heparinized saline flush affords no advantages over saline in reducing occlusion rate; however, there was a trend toward lower infection rate with the use of heparinized saline.

Catheterization, Central Venous↗