The UC San Diego Division of Regional Anesthesia is committed to providing perioperative care and postoperative pain relief on a global scale. Since 2004, Dr. Mariano has worked with the Philippine American Group of Educators and Surgeons (PAGES) as a senior pediatric anesthesiologist.

Founded in 1990, PAGES is a non-profit volunteer organization that conducts its annual Operation HOPE mission for the underprivileged children of the Philippines who are afflicted with craniofacial birth defects and deformities related to burn injuries.

Dr. Mariano has volunteered his pediatric and regional anesthesia services on multiple medical missions to the rural provinces of the Philippines.  Dr. Gloria Cheng, Regional Anesthesia Fellow 2007-08, accompanied Dr. Mariano on 2 of these missions, and Dr. Bing Feng, Regional Anesthesia Fellow 2008-09, participated in the most recent mission.

In 2006, Dr. Mariano was recruited by Project Perfect World (PPW) to participate in its annual pediatric orthopedic surgery mission to Guayaquil, Ecuador.  PPW is a humanitarian effort sponsored by the Association for Healthcare Resource & Materials Management that provides needed medical and surgical care that is otherwise unavailable to the children of third world countries. 

PPW conducts its annual Ecuador mission to care for impoverished children who are afflicted with limb deformities.  Dr. Mariano has brought a Regional Anesthesia Fellow on each of these missions (Dr. Vanessa Loland 2006, Dr. Gloria Cheng 2007, and Dr. Steven Suydam 2009).