Comparison of success rate and time to obtain venous cannulation by cutdown technique at 3 locations using canine cadavers.

OBJECTIVE: To compare the success rates and time taken to cannulate the jugular, cephalic, and lateral saphenous veins using a cutdown technique by personnel with 4 different levels of experience. DESIGN: Prospective ex vivo study. SETTING: Veterinary university teaching hospital. ANIMALS: Eighteen canine cadavers. INTERVENTIONS: Recently euthanized canine patients that were donated to the hospital for research purposes between October 2019 and March 2020 were enrolled. Four groups of personnel participated in the study to give 4 varying levels of experience: 8 final year veterinary students, 2 registered veterinary nurses, 1 emergency and critical care intern and 1 ACVECC diplomate. Each cannula placer had 5 minutes to attempt cannulation by venous cutdown at each site. Time to venous cannulation (VC) was compared for each site and group and complications encountered during each attempt recorded. MEASUREMENTS AND MAIN RESULTS: The overall success rate for cannulation of the jugular, cephalic, and lateral saphenous veins were 81%, 84%, and 87%, respectively. The median times for venous cutdown for all personnel were as follows: jugular vein 119 s (range 51-280 s), cephalic vein 82 s (range 39-291 s), and lateral saphenous vein 110 s (range 41-294 s). There was no difference in time to VC between veins. When comparing personnel at the 3 cannulation sites, the ACVECC diplomate was faster than the registered veterinary nurses and students (P = 0.042 and P = 0.048, respectively). No differences were found between any other groups. Complications encountered often related to cadaver factors such as hematoma from antemortem venipuncture. CONCLUSIONS: All groups were able to perform venous cutdown at each site with good overall success even without prior experience of the technique. VC by cutdown technique of the jugular, cephalic, or lateral saphenous veins may be considered in an emergency setting by personnel of various skill levels.

A novel alternative placement site and technique for totally implantable vascular access ports in non-human primates.

BACKGROUND: Two novel approaches to implanting a central venous catheter port in non-human primates (NHPs) using peripheral insertion are presented and compared. METHODS: Sixty vascular access port (VAP) implants were attempted in 52 NHPs by saphenous vein puncture (n = 20) or saphenous vein cutdown (n = 40). RESULTS: Fifty eight procedures were successful. Eighteen of 20 VAPs were successfully placed using saphenous vein puncture, and 40 of 40 using saphenous vein cutdown. There were no significant differences between procedures. Mean implantation times were similar between groups. At explant or study endpoint, all 58 VAPs were patent. CONCLUSIONS: Vascular access port implantation by saphenous vein puncture or saphenous vein cutdown is safe and effective in NHPs. It is less invasive than conventional procedures, has fewer complications, provides outstanding patency, and reduces surgery time. Furthermore, it allows for cooperative in-homecage VAP use, minimizing handling stress. We recommend these refined methods for long-term vascular access in NHPs.

Technical note: ruminal vein catheterization and continuous blood flow measurement in ruminal arteries of sheep.

Eight wethers were used to test the technique. Silicone rubber catheters were introduced into both ruminal veins so that their tips lay a few centimeters from the splenic vein. Arterial blood flow to the rumen was measured by an ultrasonic transit-time flow meter with 3-mm probes implanted around the left and right ruminal arteries. No loss of patency of the venous catheters was observed before slaughter (2 to 6 mo after surgery). There was no evidence of extensive vascular trauma due to catheterization at postmortem examination. In vivo calibration of the flow probes showed that reliable measurements could be made until at least 6 mo after implantation. With an accurate method of blood flow measurement in ruminal arteries and guaranteed long-term catheter patency, it would be possible to make reliable estimates of nutrient uptake across the ruminal wall of sheep over an experimental period of several months.