In Hajdik v. Wingate, 753 S.W.2d 199 (Tex. App.--Houston 1st Dist. 1988), aff'd, 795 S.W.2d 717 (Tex. 1990), the Court noted that in determining whether a party has shown surprise sufficient to preclude a pleading amendment, a trial court should consider:
(1) how long the suit has been on file before the filing of the amendment;
(2) how soon before trial the amendment was made;
(3) whether the amendment presents a new claim or cause of action;
(4) whether the new cause of action is based on recently discovered matters;
(5) whether the resisting party alleges surprise and inability to prepare to try the new cause of action. 753 S.W.2d at 204.