The catheters are inserted over a 0.35-inch guidewire through the femoral vein. "When I first started doing this – the first 10 or so patients – I did bilateral groin sticks because I’m placing bilateral pulmonary artery catheters," Dr. Engelhardt said.
He now uses a 10-French catheter that has two ports. "So I can now put catheters in each port and feed one into the right and one into the left." The catheter includes small ultrasound transducers and allows for thrombolytic drug delivery.
"I developed a protocol when I first started doing these cases. I was giving a bolus dose down each side – 4 mg each side – then I would run it for 12 hours at 0.5 mg per side. Since then, I’ve decided not to give a bolus dose but to run 0.5 mg per side for 20 hours." He now administers 20 mg total because he found that larger doses provide the same results as 20 mg but with complications such as groin hematomas.
"These catheters treat only what they’re in contact with, so I try to get these catheters as far into the periphery of the lung as I can. I’ve never had a perforation," he said.
Dr. Engelhardt is a consultant to EKOS Corp., which makes the ultrasound device.