can you buy a flare gun?
if this is not available in a confined quarters consider roman scutum wide enough in hall they can not pass or hit you they reach you use the edge of shield to mangle appendage. With a blade in other you can twist shield and stab at your leisure once you know how to twist your body. never forget blade is not your primary weapon with this set up the shield is, battering and crushing any exposed part. Think how much agony a 3/4 inch ply wood wood sheet would do if you metal rimed it and put your weight behind a foot hit. If you wanted to go further you can buy a police riot shield but most of those to heavy and are more ballistic stops.
to use a sword shield combo is HARD work 2 mins of hard fighting will have most wheezing and gasping