FARINDOLA, Italy — Using saws, shovels and their hands, rescue workers advanced slowly Saturday through the wreckage of an avalanche-destroyed hotel in central Italy, listening carefully for signs of more survivors among the 23 missing guests and hotel workers. Because of the avalanche risk, escape routes were planned for rescue crews and each participant was equipped with a tracking device in case they were buried under the snow. The heavy snowfall thwarted the arrival of equipment like cranes, said rescue spokesman Marco Bini, leaving the searchers to often rely on their hands or simple snow shovels to make progress. Rescuers passed crates full of chunks of hardened snow and ice to colleagues as they tried to penetrate deeper into the wreckage, creating the rough equivalent of elevator shafts to allow searchers to descend into the smashed hotel.