They suffered a massive setback when they had their Northern Ireland international goalkeeper Maik Taylor sent off midway through the first half and their bad luck was compounded minutes later when Liam Ridgewell suffered a suspected broken leg.
Plymouth, winners of their previous two games, took advantage of Birmingham's misfortunes when their young on-loan striker, Paul Gallagher, notched his 13th goal of the season by converting a 23rd-minute penalty which came as a result of Taylor's departure.
Birmingham are likely to appeal against the decision as, after the match, television replays indicated that the incident had taken place outside the penalty area and Taylor had made contact with the ball.
In a match of high drama Birmingham showed great courage and fought back to grab a 50th-minute equaliser from substitute Queudrue.
Taylor, who had an impressive game in the goalless draw at Charlton on Saturday when he made several fine saves to earn Birmingham a vital point, again distinguished himself early in the game when he pushed a rising drive from Jamie Mackie over the bar.
But in the 23rd minute Birmingham's victory aspirations appeared to have gone up in smoke. Taylor was in all sorts of trouble and was sent off for his clumsy tackle on Mackie who had been put clear by Alan Judge.
Referee Clive Oliver, who subsequently had a nightmare match, had no hesitation in handing Taylor a red card. Irishman Colin Doyle was immediately drafted into the side but the young keeper had no chance with Gallagher's spot-kick that gave Plymouth a surprise lead.
But even worse was to follow within a few minutes when Mackie challenged Ridgewell and the Birmingham City defender sustained a serious injury which saw him stretchered off and replaced by Queudrue.
The depleted Birmingham side surprisingly chased the game with Plymouth dropping back onto the defensive to protect their slender lead.
Chris Barker and Marcel Seip in particular were deeply involved in keeping a desperate Birmingham at bay.
After the trauma of losing two key players in such a short space of time Birmingham displayed great resolution as they tried to get back into the game.
The ever-dangerous Mackie, however, was always a persistent threat and a 30-yard deflected shot from the Plymouth striker forced stand-in goalkeeper Doyle, making his first league appearance of the season, to make a super save.
Birmingham made a dream start to the second half when substitute Queudrue moved up to head home David Murphy's free-kick after Romain Larrieu failed dismally to get to the cross.
With everything to play for Birmingham maintained the pressure on Plymouth with some relentless pressure but the winning goal eluded them as the promotion race heads to an exciting finish.