ABSTRACT
Background & objectives: Chest X-ray (CXR) is an important screening tool for pulmonary tuberculosis (TB). Accessibility to CXR facilities in difficult-to-reach and underserved populations is a challenge. This can potentially be overcome by deploying digital X-ray machines that are portable. However, these portable X-ray machines need to be validated before their deployment in the field. Here, we compare the image quality of CXR taken by a newly developed handheld X-ray machine with routinely used reference digital X-ray machine through the conduct of a feasibility study. Methods: A total of 100 participants with suspected pulmonary TB were recruited from the outpatient departments of a medical college and a community health centre in Agra. Each participant underwent CXR twice, once with each machine. Both sets of de-identified images were independently read by two radiologists, who were blinded to the type of X-ray machine used. The primary outcome was agreement between image qualities produced by these two machines. Results: The intra-observer (radiologist) agreements regarding the status of the 15 CXR parameters ranged between 74 per cent and 100 per cent, with an unweighted mean of 87.2 per cent (95% confidence interval: 71.5-100). The median Cohen’s kappa values for intra-observer agreement were 0.62 and 0.67 for radiologists 1 and 2, respectively. In addition, on comparison of the overall median score of quality of the image, the handheld machine images had a higher score for image quality. Interpretation & conclusions: The current study shows that a handheld X-ray machine, which is easy to use and can potentially be carried to any area, produces X-ray images with quality that is comparable to digital X-ray machines routinely used in health facilities.
ABSTRACT
Introduction: During limb operations tourniquets are widely used to minimize surgical bleeding and to maintain a relatively bloodless field. Tourniquet induced hypertension occurs more frequently under general anaesthesia than spinal anaesthesia and more with lower limb tourniquet than with upper limb tourniquet and can be serious in patients with cardiopulmonary diseases, neurological disease and glaucoma. This study was designed to investigate the hemodynamic effects of dexmedetomidine on prolonged tourniquet inflation. Material and Methods: Sixty patients scheduled for elective orthopaedic surgery of the upper limb under general anaesthesia were recruited. They were randomly assigned to receive intravenous dexmedetomidine (0.5 mcg/kg; n=30) or normal saline (NS group; n = 30) before tourniquet inflation. Arterial blood pressure and heart rate were recorded every 10 minutes until 90 minutes after the start of tourniquet inflation and again immediately after deflation. Result: In the dexmedetomidine group, arterial pressure was not significantly changed, but in the Control group arterial pressure was significantly increased at 90 minutes after the start of tourniquet inflation. Development of more than 30% increase in arterial pressure during tourniquet inflation was more frequent in the Control group than in the dexmedetomidine group. Conclusion: Preoperative intravenous dexmedetomidine could therefore prevent tourniquet-induced hypertension in patients undergoing general anaesthesia.