Development of a surgical instrument for measuring forces applied to the ossicles of the middle ear.

Surgery of the middle ear is a delicate process that requires the surgeon to manipulate the ossicles, the smallest bones in the body. Excessive force applied to the ossicles can easily be transmitted through to the inner ear which may cause a permanent sensorineural hearing loss. An instrument was required to measure the forces applied to cadaveric temporal bone ossicles with the vision of measuring forces in vivo at a later stage. A feasibility study was conducted to investigate a method of measuring force and torque applied to the ossicles of the middle ear. Information from research papers was gathered to determine the expected amplitudes. The study looked at commercially available transducers as well as constructing an instrument using individual axis transducers coupled together. A prototype surgical instrument was constructed using the ATI industrial automation Nano17 six axis transducer. The Nano17 allows for the measurement of force and torque in the X, Y and Z axis to a resolution of 1/320 N. The use of the Nano17 enabled rapid development of the surgical instrument. It meets the requirements for its use on cadaveric models and has the potential to be a useful data collection tool in vivo.

Towards improved sedation control in critically ill patients.

Patients in intensive care units are often prescribed a combination of sedative and analgesic to manage anxiety and pain relief. Proper sedation management is crucial to patient recovery but few intensive care units routinely employ strategies that tailor drug delivery to ongoing patient needs. The Infuse-Rite has been developed to automate a protocol that eliminates the possibility of excessive sedation. Changing clinical demands have provided the impetus for ongoing enhancements to improve the sedation control of patients in intensive care.