Multi position ask and bid

I use the following code to calculate the highest number of pips a single position or set of positions goes against a trade. So, if it goes 20 pips against you and then comes back, at the close of the trade I know how far it drew down the account for strategy analysis purposes.

foreach(Position position in Positions)
                {
                    if (position.TradeType == TradeType.Buy)
                    MaxDrawDown = Math.Max(Math.Round((position.EntryPrice - Symbol.Bid) / Symbol.PipSize, Symbol.Digits), MaxDrawDown);
                    else
                    MaxDrawDown = Math.Max(Math.Round((Symbol.Ask - position.EntryPrice) / Symbol.PipSize, Symbol.Digits), MaxDrawDown);
                } 

it will only work with single currency.  because it subtracts from the Symbol.Bid(or Ask)  How can I get this o work with multiple currencies there is no bid or ask in the position object.  I assume I could use position.symbolcode to get the currency pair but then how do I use that to return the pairs ask and bid?