Safety measures for conducting exercise oxygen consumption, VO2, tests in developing countries

Measurements of rate of oxygen consumption (VO2) recorded during controlled exercise is used to assess cardiovascular health in test individuals. In low- or middle-income countries, where Mycobacterium tuberculosis is common and older VO2 systems are in use, three specific preventative measures should be in place to prevent the transmission of tuberculosis. These include: (1) disinfecting reusable plastic masks and rubber tubing with bleach solution; (2) limiting maximum exposure of test individuals to Cl2 gas to <1–3 ppm for a duration of ≤15 min to prevent respiratory distress; and (3) carefully inspecting for degradation of plastic VO2 masks and rubber tubing repeatedly disinfected with bleach and replace these at the first signs of deterioration.

Development and Assessment of a Microcomputed Tomography Compatible Five Degrees-of-Freedom Knee Joint Motion Simulator

Currently available knee joint kinematic tracking systems fail to nondestructively capture the subtle variation in joint and soft tissue kinematics that occur in native, injured, and reconstructed joint states. Microcomputed tomography (CT) imaging has the potential as a noninvasive, high-resolution kinematic tracking system, but no dynamic simulators exist to take advantage of this. The purpose of this work was to develop and assess a novel micro-CT compatible knee joint simulator to quantify the knee joint's kinematic and kinetic response to clinically (e.g., pivot shift test) and functionally (e.g., gait) relevant loading. The simulator applies closed-loop, load control over four degrees-of-freedom (DOF) (internal/external rotation, varus/valgus rotation, anterior/posterior translation, and compression/distraction), and static control over a fifth degree-of-freedom (flexion/extension). Simulator accuracy (e.g., load error) and repeatability (e.g., coefficient of variation) were assessed with a cylindrical rubber tubing structure and a human cadaveric knee joint by applying clinically and functionally relevant loads along all active axes. Micro-CT images acquired of the joint at a loaded state were then used to calculate joint kinematics. The simulator loaded both the rubber tubing and the cadaveric specimen to within 0.1% of the load target, with an intertrial coefficient of variation below 0.1% for all clinically relevant loading protocols. The resultant kinematics calculated from the acquired images agreed with previously published values, and produced errors of 1.66 mm, 0.90 mm, 4.41 deg, and 1.60 deg with respect to anterior translation, compression, internal rotation, and valgus rotation, respectively. All images were free of artifacts and showed knee joint displacements in response to clinically and functionally loading with isotropic CT image voxel spacing of 0.15 mm. The results of this study demonstrate that the joint-motion simulator is capable of applying accurate, clinically and functionally relevant loads to cadaveric knee joints, concurrent with micro-CT imaging. Nondestructive tracking of bony landmarks allows for the precise calculation of joint kinematics with less error than traditional optical tracking systems.

Endoscopic vocal fold injection using a 25-gauge butterfly needle

Objective:To describe a useful technique for infiltrating a bulking agent using a butterfly needle, as part of a transoral endoscopic vocal fold medialisation procedure.Methods:This paper describes the procedure of grasping the needle with phonosurgery forceps and administering the injectate to the vocal fold through careful application of the syringe plunger via a length of rubber tubing from outside the mouth.Results:This procedure is performed routinely in our institution without complication. The advantages of this technique are discussed.Conclusion:This is a safe and easy method of injecting into a vocal fold.

Nasal and Facial Reconstruction in a Dog Following Severe Trauma

Successful reconstruction of the nasomaxillary region requires closure of oronasal communication and maintenance of a patent upper airway. A dog with traumatic amputation of the nasomaxillary region was presented for reconstructive surgery. Staged surgical procedures were performed with the goal of closing the oronasal fistula, reapposing facial tissues, forming a granulation bed in each nasal passage, and harvesting and placing mucosal grafts in the nasal passages. A novel technique for developing a granulation tissue bed for mucosal grafts using silicone rubber tubing was employed. The end result of the reconstructive surgeries was a relatively cosmetic appearance with patent nasal openings.