Diane:

Please don’t take this as condescending, but I’m missing something here. You are concerned with CHF exacerbation at 2.0 ATA, but you are willing to treat (suboptimally … with no scientific data showing clinical improvement) at 1.5 ATA.

No, I wouldn’t recommend doing this. I think the risk of exacerbation of CHF is nearly the same between the two pressures. It’s been awhile since I reviewed the venous displacement from HBO exposure, but I’m thinking 400 - 500 cc during a treatment.

So, here’s my recommended plan. Ask your friendly cardiologist to evaluate the patient. If he/she feels that the patient is on optimal therapy, then consider an appropriate HBO exposure for whatever diagnosis you are treating. If the cardiologist is concerned that 400cc increase in venous return will put this patient in jeopardy, don’t do it.

I’m assuming a monoplace chamber. That would make it simple. If the patient exhibits clinical changes during the treatment, terminate it.

In my experience and review of the literature, patients with ejection fractions down to 25% or so, can be managed if careful and with optimal help from the cardiologist. That said, there are case reports of patients with 35 - 40%EF who had flash pulmonary edema.

So, this is an interesting question and one where clinical management is absolutely necessary.

Hope this helps.

gene