PubMed Health⌕ Search

Biomedical subjects

C V Prasad

Publications and source records attributed to C V Prasad.

At least 19 recordsLinked to original sources

Abdominal muscle action during expiration can impair pressure controlled ventilation.

Pressure controlled ventilation, and pressure support for spontaneous breathing are often used in intensive care because coordination of the ventilator with patient efforts can improve comfort and possibly reduce sedation. However we report a series of 10 patients whose efforts did not synchronise with pressure controlled ventilation. This was incorrectly diagnosed as inadequate sedation, and treated with increased sedation or muscle paralysis. Better recognition of this condition showed that slow respiratory rates and increased abdominal muscle action during expiration can affect pressure-controlled ventilation and pressure assisted breathing. If the condition is not recognised, treatment for poor synchronisation may delay weaning or be inappropriate.

Abdominal Muscles↗

Outcome of compartment syndrome following intramedullary nailing of tibial diaphyseal fractures.

Seventeen cases of compartment syndrome were treated in a group of 626 consecutive patients with tibial diaphyseal fractures. Clinical and radiological follow-up was performed at an average of 24 months (range 8-54 months). Functional outcome was assessed using Edward's classification. All patients who developed compartment syndrome had fracture stabilisation with a reamed intramedullary nail using skeletal traction. The average interval between the nailing procedure and fasciotomy was 11 h. Results were good in 10 cases, fair in four cases and poor in the remaining three cases. Patients who had decompression within 12 h had a good functional outcome. Patients with poor results were all treated at an interval greater than 24 h.

Adult↗

Wound complications following operative fixation of calcaneal fractures.

The aim of our study was to find the incidence of wound complications following operative fixation of fractured calcanea and identify the risk factors contributing to them. We retrospectively reviewed the results of operative treatment of 33 calcaneal fractures in 30 patients over a 4-year period. We report an overall wound complication rate of 18.1%. Wound infection, haematoma, dehiscence and heel necrosis were noted in our series with or without underlying osteomyelitis. We identified the following as risk factors to the causation of post-operative wound complications: (a) fall of more than 3.4 m (p<0.005); (b) surgery within 7 days (p<0.05); (c) operating time in excess of 2 h (p<0.05); (d) tourniquet time in excess of 1.5 h (p<0.001). We recommend careful attention to these factors in treating calcaneal fractures.

Adult↗

CT assessment of torsion following locked intramedullary nailing of tibial fractures.

The aim of our study is to determine the incidence and extent of torsional malalignment in patients with tibial diaphyseal fractures treated with closed antegrade intramedullary (IM) nailing. We measured torsion using CT scanning in 22 patients. A difference of 8 degrees or more was found in 8 cases (36%) as compared with the uninjured side. Only 2 of these cases could be clinically detected and only one patient noted the problem. We also describe a method of directly calculating torsion from CT images captured on a single film that is easy and does not require any special equipment.

Cohort Studies↗

Simultaneous determination of tinidazole, furazolidone and diloxanide furoate in a combined tablet preparation by second-derivative spectrophotometry.

A second-derivative spectrophotometric procedure has been developed for the simultaneous determination of tinidazole (TD), furazolidone (FD) and diloxanide furoate (DF) in a commercial preparation. The method consists of the utilization of second-derivative absorption spectra of tablet extract in distilled water and then determination of the analyte concentration in the mixture was carried out using zero-crossing (ZC) and ratio-compensation (RC) techniques. Calibration graphs constructed at their wavelengths of determination were linear in the concentration range of TD (5-20 microg ml(-1)), FD (2.5-10 microg ml(-1)) and DF (7.5-15 microg ml(-1)). The results were found to be accurate and free from interference. The details of the statistical treatment of analytical data are also presented.

Antiprotozoal Agents↗

Simultaneous quantitative determination of metronidazole and nalidixic acid in tablets by difference spectroscopy.

A difference spectrophotometric procedure has been developed for simultaneous determination of metronidazole (MDZ) and nalidixic acid (NA) in tablets. The method comprised the measurement of the absorbance of a solution of the tablet extract in 0.1 M NaOH relative to that of an equimolar solution in 0.1 M HCl at 292 nm for NA and 325 nm for MDZ. The presence of identical isosbestic points for pure drug solutions and tablet extracts indicated the non-interference of excipients in the absorption at these wavelengths. Compliance with Beer's law was observed in the concentration ranges 5-25 micrograms ml(-1) for MDZ and 15-35 micrograms ml(-1) for NA these wavelengths.

Anti-Infective Agents↗

Hemostatic alterations in non-cirrhotic portal fibrosis, extrahepatic portal venous obstruction and Budd-Chiari syndrome.

We studied the coagulation function in ten patients each with non-cirrhotic portal fibrosis (NCPF), extrahepatic portal venous obstruction (EHPO) and Budd-Chiari syndrome (BCS), conditions where venous thrombosis in the hepatic vasculature is a common denominator. Prothrombin time, partial thromboplastin time with kaolin (PTTK) and thrombin time were normal in patients with NCPF and EHPO. However, in BCS the PTTK was prolonged, with a mean test/control ratio of 1.68 +/- 0.11. Fibrin degradation products were absent in all patients. Platelet aggregation tests showed hypoaggregability in all patients with NCPF. They were normal in patients with EHPO. However, two of ten BCS patients showed hyperaggregability, coinciding with a recent onset of illness in one patient. In conclusion, coagulation abnormalities appear unlikely to be the cause of thrombosis in patients with NCPF and EHPO. Further studies are required to substantiate the findings of hyperaggregability of platelets in BCS.

Adolescent↗

Counterion distribution around DNA: variation with conformation and sequence.

The three-dimensional Poisson-Boltzmann equation for the distribution of counterion charge density around double helical DNA has been solved by an iterative procedure. These computations have been performed for 0.01M monovalent salt solutions. A systematic study of the ten possible sequences found among adjacent nucleotide base pairs is presented for the A, B, and C conformations of DNA. In addition, calculations of the electrostatic stabilities of these conformations of DNA allows for comparison of the charge accumulation around each of the three conformers.

Base Sequence↗

A program to calculate non-bonded interaction energy in biomolecular aggregates.

This paper describes a program to calculate intermolecular as well as intramolecular electronic potential energy resulting from non-bonded interactions. The underlying theory is obtained by the application of Rayleigh-Schroedinger perturbation theory to non-overlap regions of a molecular system. The rigorous theoretical expressions for the energy terms are simplified by approximations consistent with those commonly employed in semi-empirical molecular orbital theories. The program is particularly suited for the study of biomolecular assemblies, and in situations where insight into contributions to total energy from various component interaction types is desired. The inclusion of the non-additive dispersion effects in this approach makes it especially interesting for the study of cooperative phenomena in the light of a recent finding [1].

Computers↗