Effect of heated-air blanket on the dispersion of squames in an operating room.

High-fidelity, predictive fluid flow simulations of the interactions between the rising thermal plumes from forced air warming blower and the ultra-clean ventilation air in an operating room (OR) are conducted to explore whether this complex flow can impact the dispersion of squames to the surgical site. A large-eddy simulation, accurately capturing the spatiotemporal evolution of the flow in 3 dimensions together with the trajectories of squames, is performed for a realistic OR consisting of an operating table (OT), side tables, surgical lamps, medical staff, and a patient. Two cases are studied with blower-off and blower-on together with Lagrangian trajectories of 3 million squames initially placed on the floor surrounding the OT. The large-eddy simulation results show that with the blower-off, squames are quickly transported by the ventilation air away from the table and towards the exit grilles. In contrast, with the hot air blower turned on, the ventilation airflow above and below the OT is disrupted significantly. The rising thermal plumes from the hot air blower drag the squames above the OT and the side tables and then they are advected downwards toward the surgical site by the ventilation air from the ceiling. Temporal history of the number of squames reaching 4 imaginary boxes surrounding the side tables, the OT, and the patient's knee shows that several particles reach these boxes for the blower-on case.

Assessment of transcervical chorion villus aspiration biopsy in early pregnancy.

BACKGROUND: Chorionic villus sampling for prenatal diagnosis is a relatively new technique and variable success rates have been reported by different authors depending on the methods and instruments used. We describe our experience with chorionic villus sampling in Bombay. METHODS: The procedure was attempted on 62 women before termination of their pregnancy via the transcervical route, under constant real-time ultrasound guidance. A metallic cannula was negotiated through the cervix into the uterine cavity to reach the chorionic frondosum and chorionic villi were aspirated by creating a negative pressure in the syringe attached to the cannula. The villus tissue was checked under a dissecting microscope. We calculated the success rate for obtaining a sample depending on the site of the chorionic frondosum, the physique of the mother, the position of the uterus and the size of the cannula. RESULTS: Villus tissue was aspirated in 47 of the 62 cases. The success rates of sampling at the first and second attempts were 48% and 27% respectively. The factors which were associated with a higher success rate were when the chorionic frondosum was situated posteriorly rather than anteriorly (61% v. 48%; p < 0.01), when the patient was thin rather than fat (58% v. 25%; p < 0.001), when the uterus was anteverted rather than retroverted (53% v. 41%). The commonest complication was bleeding which occurred in 15% of patients. CONCLUSION: Transcervical chorionic villus sampling is associated with a high success rate except in fat women with a retroverted uterus and in those with the chorionic frondosum situated in the fundus.

Mono ferrous acid citrate (FeC6O7H2O) as an iron fortificant.

1. Iron absorption from ferrous citrate (monoferrous acid citrate, FeC6H6O7H2O) was studied in normal healthy male and female volunteers using ferrous citrate labelled with radioactive Fe and whole-body counting. Ferrous citrate was either given alone or with a rice-based meal. 2. Fe absorption from ferrous citrate was satisfactory and was comparable to that from ferrous sulphate. 3. Fortification of crude cooking salt with ferrous citrate was not satisfactory due to colour development on storage. Ferrous citrate can, however, serve as an effective Fe fortificant with sugar or wheat flour.