The Italian suffered the first defeat of his second spell at the helm after a 2-1 defeat at struggling SPAL on Saturday.
Ahead of the Milan derby, the Stadio Olimpico club remain in fifth, three points off the Serie A top four.
Defeat comes 10 days after their exit from Europe's premier club competition, which led to the sacking of Eusebio di Francesco and the return of Ranieri until the end of the campaign.
And Ranieri says he will advise the Roma hierarchy to stage a mass overhaul if the club fail to achieve their primary goal.
"If Roma goes to the Champions League there is a program, if you don't go, you change them," he told Sky Sport Italia. "I've told them too. They have to earn what they earn.
"We lost against a team that earns less and has water to the throat. If there is a revolution? Without the income of the Champions League something must change."
Mohamed Fares gave SPAL a first-half lead before half-time substitute Diego Perotti equalised for the visitors.
The relegation-threatened home side got the winner from the penalty spot, after a VAR decision gave the hosts the chance following a Juan Jesus foul on Andrea Petagna.
Petagna stepped up to inflict upon the Roma club their seventh league reverse of the campaign.
Ranieri was critical of Roma's application throughout the contest though admitted his side showed plenty of fight.
"We have only put in hard work but without organisation," the ex-Leicester boss added. "It is not good, we lost all the duels. SPAL broke our rhythm.
"Evidently there are some players who at this time are not playing with confidence and are not determined to win duels."
Referring to the penalty decision, he added: "We cannot see everything from the bench, we must be less controversial and try to help the referees. Even the men of VAR need experience. I am positive".