Complex sentence: American loans financed road construction and public health with the United States employing more than 10,000 Salvadorans in the Panama Canal Zone, with Salvadorian wages arranged sent back home.
Split into simpler sentences: American loans financed road construction and public health improvement. Furthermore, the United States employed more than 10,000 Salvadorans in the Panama Canal Zone, and arranged to have part of their wages sent back home.