Arterial catheter setup for glucose control in critically ill patients: a randomized controlled trial

BACKGROUND

Use of an arterial catheter to obtain hourly blood samples for intensive insulin therapy monitoring avoids causing patients the discomfort of repeated fingersticks. Returning the clearing volume may decrease procedure-related blood loss by 50% and minimize the risk of anemia.

OBJECTIVES

To compare the feasibility of 2 arterial catheter clearing-volume return setups for hourly blood extractions and to evaluate the related complications and the accuracy of arterial samples in determining glycemia.

METHODS

In an open clinical trial, 90 critical patients undergoing intensive insulin therapy who had a radial arterial catheter were randomized to an intervention group-nonwaste needleless setup or nonwaste syringe setup and compared with the standard setup (control group). Mechanical and infectious complications related to the arterial catheter were evaluated. Blood glucose measurements at point-of-care glucometer (arterial catheter or fingerstick sample) were compared with laboratory results (venous blood).

RESULTS

No patient had catheter-related infection in the intervention group (an estimated 12776 manipulations); the control group had 2 infection episodes in 5230 catheter-days (an estimated 13 075 manipulations). The incidence of bacterial colonization was not significantly higher in the needleless group than in the syringe group (22.2% vs 12.2%; relative risk, 0.55; 95% CI, 0.16-1.71), with 1778 (SD, 114) and 1918 (SD, 82) catheter manipulations, respectively. Arterial catheter complications were negligible in all patients. Glycemia was detected from arterial catheter samples as effectively as with laboratory results (venous samples) except when hematocrit was less than 25%.

CONCLUSIONS

Use of blood obtained via an arterial catheter is safe and effective for glucose monitoring in patients undergoing intensive insulin therapy, with no increase in complications of catheterization.

Density of microbial colonization on external and internal surfaces of concurrently placed intravascular devices

BACKGROUND

Intravascular devices provide essential vascular access for management of critically ill patients but can be associated with bloodstream infections.

OBJECTIVES

To determine colonization rates in segments of concurrently placed peripheral arterial, nontunnelled short-term central venous catheters and peripherally inserted central catheters and the pattern of heaviest colonization when the catheters are removed.

METHODS

A prospective study was conducted on inpatients with intravascular devices in place for 9 days or more. At removal, each catheter was cut into 3 segments, and each segment was cultured separately. The density of colonization on external and internal surfaces of each segment was compared by estimating odds ratios by repeated-measures ordinal logistic regression.

RESULTS

A total of 48 peripheral arterial, 135 central venous, and 106 peripherally inserted central catheters were obtained from 289 patients. Colonization was greatest at the proximal external segment of all catheters. On the external surface, colonization was lower on the middle (odds ratio, 0.70; P < .001) and distal (odds ratio, 0.56; P < .001) segments than on the proximal segments. On the internal surface, colonization was lower on the proximal (odds ratio, 0.39; P < .001), middle (odds ratio, 0.30; P < .001), and distal (odds ratio, 0.31; P < .001) segments than on the external proximal segments. This trend was similar for all catheter types.

CONCLUSION

Colonization of intravascular devices was heaviest on proximal segments.