The use of alternative adult laryngoscope blades in an unexpected difficult intubation was evaluated with a human patient simulator manikin. Twenty anaesthetists of varying experience attempted to intubate the trachea of a high fidelity simulator in both its normal and difficult intubation settings using Macintosh, Dorges and McCoy laryngoscopes in a randomised order. The time taken to intubate, Cormack and Lehane scores, percentage of glottic opening visible, failure rate, number of attempts and subjective ease of use were recorded. The Dorges and McCoy blades did not perform any better than the standard Macintosh blade in either the easy or difficult tracheal intubation settings. Guidelines recommending the use of an alternative blade in an unexpected difficult intubation scenario have limited supporting evidence. This study does not support this recommendation.