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

Objective: 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.

Study Design: Prospective blinded comparison of techniques. Retrospective analysis of case records.

Animals: 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).

Methods: 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.

Results: 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.

Conclusions And Clinical Relevance: 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.