Nui nā kumu o ke keʻakeʻa ʻana o ka ʻōpū, a ʻo ka mea maʻamau ka poʻe maʻi me nā maʻi maʻi ʻino like ʻole, ʻoi aku ka nui o nā maʻi maʻi ʻeha. Wahi a nā helu helu ʻole, e pili ana i ka 30% o nā mea maʻi me nā maʻi maʻi digestive tract e ʻike i nā pae like ʻole o ka obstruction, e alakaʻi pololei ana i ka hiki ʻole o ka poʻe maʻi ke ʻai maʻamau, i hele pū ʻia me ka ʻeha o ka ʻōpū, bloating, a i nā hihia koʻikoʻi, gastrointestinal perforation, a hiki nā kūlana hoʻoweliweli.