Electrocardiography-guided and retrospective analysis of central venous catheter placement in the dog

To compare the success rates of central venous catheter placement (CVCP) in dogs using electrocardiograph (ECG)-guided and external landmark ('blind') techniques. To report success rates determined retrospectively of CVCPs in dogs using external landmarks at a tertiary referral institution.

Prospective blinded comparison of techniques. Retrospective analysis of case records.

Adult Beagles weighing 11.9 +/- 2.6 kg were used in the experimental group (n = 38). Various breeds of dogs were in the retrospective clinical group (n = 33).

Laboratory dogs were anesthetized and CVCPs were placed using a modified Seldinger technique. Catheter tip position was first based on external landmarks and then the catheter was repositioned using an ECG-guided placement. The ECG-guided technique used the V-lead with the positive electrode attached to the guide wire. Catheter placement was determined by moving the catheter cephalad and caudad to the point of maximum p-wave amplitude and then withdrawing the catheter 1-2 cm from this point. Catheter position with each technique was determined using a lateral thoracic radiograph. Retrospective data were collected from the medical records of dogs that had CVCPs using anatomical landmarks and corresponding thoracic radiographs.

The number of successful CVCP attempts was the same for both prospective groups (21/38). There was no statistically significant difference in success between the ECG-guided technique and the blind technique. From the retrospective investigation 10/33 of the cases that fit the criteria had correct CVCPs.

The odds of correctly placing a central venous catheter by ECG-guidance were the same as the external landmark technique. The ECG-guided technique may be useful in situations where external landmarks are not readily available.