Why did I get broken capillaries after pulse dye laser for rosacea?

As mentioned, efficacy from pulsed dye lasers is related to destruction of blood vessels with expected bruising and unfortunately, potential for hyperpigmentation, hence the need to use such products. Link is provided for more information.You may be undertreated with the pulsed dye technology. 
Pulsed dye laser can cause bruising and swelling and I precondition and treat my patients with a bioflavonoid product called Swell-x pt (post treatment) and also an oral supplement for PIH relief called Scler-X and I find them to be effective. 
For hyperpigmentation relief we use a HQ and non HQ based creams in  the U.S. called Melarase.
Best to inform the physician under whose guidance you got these results.
Hratch L Karamanoukian MD FACS

I have been using the Pulsed Dye
Laser for over 25 years and have never seen this happen. My guess is that you
are being undertreated. A sub therapeutic treatment could irritate and inflame
your Rosacea causing it to worsen and stimulate new vessel formation. A certain
energy threshold is needed for a laser treatment to be successful. Being too
gentle can actually have the opposite intended effect. This is commonly seen in
laser hair removal. When the laser energy is sublethal, the hair follicle can
be induced to grow rather than destroyed, resulting in increased hair rather
than hair destruction.

I have not come across this before. The before and afters will tell the story. Every patient should have standardised before photos, if you could attach the after, we can perhaps make an educated comment.  I do not have a logical explanation without photos. Rosacea is very complex and a tailored treatment program give the best results. This is because there are many types of rosacea (telengtctatic or capillaries, flushing and redness, acne like rosacea, ocular rosacea and even rhinophyma rosacea.)
To add to the complexity, everyone has different flare factors- Sunlight, stress, foods, chemical irritants, creams, changes in temperature, alcohol. The list goes on. 

A detailed history, together with a treatment tailored according to YOUR type of rosacea will give the best results. As a guide, I use a combination of -

1. Lasers ( to treat redness, broken capillaries, rhinophyma, flushing)- best laser is the V BEAM. IPL can be used, but usually not as effective. Laser toning using the long pulse Nd Yag at 1064 can help with background redness. 

2. Creams - anti inflammatory

3. Tablets -anti - inflammatory and sometimes low dose Vitamin A. 

4. For females- Mineral make up is recommend, over make up that contains parabens. 

For the best results, consult a dermatologist for both medical and laser treatment options. 

Kind regards.

Dr Davin S. Lim.

Laser Dermatologist.

Brisbane, Australia.