A comparison was made of arterial pressures measured invasively from a radial arterial cannula and non-invasively from the middle finger using the 2300 Finapres (Ohmeda) during induction and maintenance of anaesthesia. Digital outputs of both pressures were captured directly onto computer hard disk; data recorded during flushing of the arterial line were excluded from analysis. We studied 53 patients undergoing cardiac, major vascular and neurosurgical procedures; 17705 comparisons of systolic, diastolic and mean pressure were analysed. Overall correlations between Finapres and invasive pressures were poor (r = 0.82, 0.68 and 0.78 for systolic, diastolic and mean pressures, respectively). The Finapres exhibited a high level of accuracy and precision in some recordings. However, patient data sets showed marked variability in average pressure differences (invasive minus Finapres) when examined individually or grouped by operation type. Unexplained variations in pressure difference with time and absolute pressure were observed also. Whilst providing useful beat-to-beat information on arterial pressure trends, the Finapres cannot be recommended as a universal substitute for invasive arterial pressure monitoring.

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The science of bone grafting has been employed for bone repair for hundreds of years. Bone grafting has developed into a unique scientific endeavor that is essential to many surgical disciplines. Orthopedic surgeons may be responsible for pioneering bone grafting, but since World War II, other specialists also have been extensively involved. Plastic surgeons have used bone grafting throughout the body. Foot and ankle surgeons have found multiple uses for harvesting and grafting bone in the foot and ankle. Otolaryngologists and oral and maxillofacial surgeons use bone grafts in facial reconstruction. Surgeons must be adept in bone graft harvesting and must have a thorough understanding of the biologic characteristics of the graft. Additionally, surgeons must assess final outcomes and appreciate potential complications. 1,2 Most of the traditional reconstructive methods are rather invasive and associated with certain amount of morbidity. The impetus of this study is to obviate donor-site morbidity. Bony defects created in maxilla and mandible, secondary to trauma, pathology, metabolic bone disorders, congenital anomalies, infection, and periodontal diseases, need to be filled with appropriate bone graft materials for esthetic and functional purposes. A multitude of bone graft materials have been used to fill such defects but all are associated with some shortcomings. Traditionally, the augmentation of bony defects is carried out using autogenous bone, allografts, alloplasts, and xenografts. Several synthetic bone graft substitutes have been used with variable degree of success, such as bioactive glasses, aluminum oxide, calcium sulfate, calcium phosphate, alpha and beta tricalcium phosphate, synthetic hydroxyapatite. These materials may not necessarily be used solely for reconstructive procedures, but when used in right situation in combination with autografts, allografts, or other synthetics they have the potential for more desirable results. Synthetic materials have also been developed for use as bone graft substitutes. Advantages of synthetic materials include tunable resorption rates, controlled porosity, higher mechanical strength compared with demineralized bone matrix products, ideal processing, and molding parameters. However, these materials lack inherent native growth factors due to which there is an absence of osteoinductive properties.