@Tdg4 welcome to the forum! You have an interesting question about PTSD, Trauma and dysautonomia. I have HPOTS ( thought to be genetic since it affects women in three generations in my family ) as well as PTSD and ADHD. I have underwent extensive neuro-psychologic testing, am currently and have been in counseling for the PTSD. I also was positively diagnosed for POTS with lab tests and TTT. The neuro-psychologist states that my symptoms are NOT related to anxiety or trauma.
I went through a rough time emotionally a year and a half ago but it has not affected my POTS, or worsened the symptoms in any way, neither has the therapy. However - therapy for PTSD can be very scary and stressful since the goal is to have you come to terms with the trauma and learn healthy ways to deal with it. This will trigger the trauma recall and the pure stress of this can potentially trigger an abnormal autonomic response, as ANY stress can.
What is always best when going through a flare is ample rest, mild exercise and lots of fluids, as well as good self care and diet. To most breathing exercises can be helpful, your therapist may be able to teach you some. Be gentle with yourself, and talk to your therapist about your symptoms as well as your doctor. Let us know how you are getting along - be well!