I have seen medical plans sold from at least a couple of Dominican companies that have an International Option. Do check the limits and restrictions. Here is one example:
https://www.universal.com.do/productos_parati/salud local premium/Paginas/Exclusivo_Plus.aspx
Google Translation:
Deductible Compensation: claims for local detention will be considered deductible in case of international detention.
Free of coinsurance in internment.
3 deductible options: US $ 3,000; US $ 5,000; US $ 10,000
Life Coverage.
Maximum benefit per year US $ 1,000,000 international and RD $ 10,000,000 local.
Access to the highest medical technology and a prestigious network of providers Worldwide.
100% coverage in outpatient diagnoses and hospitalization.
$ 500,000 for organ transplantation, with no international case limit.
100% coverage by local and international ground ambulance.
International benefits:
100% coverage in laboratories of the prestigious Quest Diagnostic Network .
Free coverage for one (1) year in Travel Assistance, which includes the following coverage and limits: