Biomedical subjects
Ramesh Agarwal
Publications and source records attributed to Ramesh Agarwal.
Diffuse neonatal haemangiomatosis without cutaneous involvement.
Explore the source record for details and available documents.
Hand-foot-and-mouth disease in Calicut.
OBJECTIVE: Hand-Foot-and-Mouth Disease (HFMD) is a mild exanthematous illness seen worldwide, affecting mainly children under ten years of age. The causative agents were initially Coxsackie virus type A 16 and related serotypes. The situation changed drastically about thirty years ago with the advent of a new aetiological agent, Enterovirus type 71 (EV 71), which has caused very large outbreaks with severe complications and many deaths. METHODS: The authors report an outbreak of papulovesicular lesions on the skin and oral mucosa compatible with the diagnosis of HFMD in children in and around Calicut in October 2003. Clinical and laboratory study in collaboration with the National Institute of Communicable Diseases, Delhi. Eighty one children with the syndrome were examined and followed up from October 2003 to February 2004, when the outbreak subsided. RESULT: The outbreak was mild and all children recovered within 1 to 2 weeks. CONCLUSION: Acute and convalescent paired serum samples collected from 19 patients were examined at the NICD for IgM antibody against EV 71 by microneutralisation test in cell culture. All the paired samples tested showed significant rise in titre of antibodies, confirming the diagnosis of EV 71 infection in each of them.
Factors affecting the accuracy of pressure measurements in vascular stenoses from phase-contrast MRI.
In this work the effects of noise, resolution, and velocity (flow) on the measurement of intravascular pressure from phase-contrast (PC) MRI are discussed. To elucidate these effects, we employed an axisymmetric geometry that enabled us to calculate pressures in <2 min on a Sun Ultra SPARC 10 workstation. To determine the effects of vascular stenoses, we fabricated several stenotic phantom geometries (with 50%, 75%, and 90% area stenoses), and performed both MRI and computational fluid dynamics (CFD) simulations for various flow rates for these phantom geometries. Noise with Gaussian statistics was added to the velocity field obtained from the CFD simulations. The pressure maps obtained directly from CFD simulations for our phantom geometries were compared with pressure maps derived by our algorithm when 1) the input was noise-corrupted velocity data from CFD, and 2) the input was PC-MRI data collected from the phantoms. The quantitative effects of noise, resolution, and flow rate on the accuracy of pressure measurements were determined. We found that for flow rates below the Reynolds number for turbulent flow, resolution is a more significant determinant of accuracy than SNR. Furthermore, if other parameters remain constant, increased flow rates may result in decreased accuracy.
Effect of fortification with human milk fortifier (HMF) and other fortifying agents on the osmolality of preterm breast milk.
This study was conducted to test the effect of fortification with human milk fortifier (HMF), low birth weight (LBW) formula and coconut oil, initially and upon subsequent storage, on the osmolality of preterm breast milk. Milk samples (n = 48) were collected from mothers (n = 25) delivered at 34 pounds weeks and fortified with HMF (Lactodex-HMF), LBW formula (Lactodex-LBW) and edible coconut oil. Osmolality was measured before and after fortification and after 6 hours,.The gestation and birth weight (median) was 31 (range 29-32) weeks and 1198 (range 716-1478) grams. The median (range) postnatal age at testing was 15 days (range 3-60 days). There was a significant increase in osmolality of breast milk (302.3 +/- l.82) after addition of HMF (392.9 +/- 3.01) and LBW formula (390.5 +/- 2.4). There was no change in osmolality with addition of coconut oil (304 +/- 1.6). There was no further change in the osmolality after 6 hours of storage at 4 degrees C.
Efficacy of oral phenobarbitone in term "at risk" neonates in decreasing neonatal hyperbilirubinemia: a randomized double-blinded, placebo controlled trial.
OBJECTIVE: To evaluate the efficacy of oral phenobarbitone in "at risk " term neonates (with high cord bilirubin) in decreasing hyperbilirubinemia. DESIGN: Double blind, placebo-control, randomized trial. SETTING: Tertiary level neonatal unit. OUTCOME: Primary-hyperbilirubinemia defined as total serum bilirubin (TSB) greater than 13 mg/dL. Secondary-TSB at 72 +/- 12 hr, need for phototherapy or exchange transfusion and side effects of phenobarbitone therapy. METHODS: All consecutively born term healthy neonates with cord bilirubin > or = 2.5 mg/dL were randomly assigned to receive either phenobarbitone (n = 37) or placebo (n = 38) after obtaining informed consent. Phenobarbitone was administered orally (5 mg/kg/day) for 3 days starting within 12 hours of birth. The neonates were followed up till seven days of life. TSB was estimated in neonates who developed jaundice with clinically assessed level of 8-10 mg/dL and at 72 +/-12 hours of age in 55 neonates. RESULTS: The baseline characteristics were similar in two groups. There was no significant reduction in incidence of hyperbilirubinemia in phenobarbitone group compared to in placebo group (6/37 (16.2%) versus 13/38 (34.3%); RR 0.47, 95% confidence interval: 0.20-1.11; risk difference: -18.1%, 95% confidence interval: -39.5 to 3.3%). However TSB at 72 +/-12 hours in phenobarbitone group (mean +/- S.D: 10.0 +/- 3.7 mg/dL) was significantly lesser than in placebo group (mean +/- S.D: 12.3 +/- 3.3 mg/dL) (difference of means: -2.3 mg/dL, 95% confidence interval: -3.9 to -0.7 mg/dl, P = 0.018). No significant difference with respect to need for treatment was observed in two groups. No significant adverse effects of phenobarbitone were noted. CONCLUSIONS: Prophylactic phenobarbitone is not helpful in reducing the incidence of hyper-bilirubinemia in "at risk" term neonates.
The challenges of imaging based computational fluid dynamics.
Image based Computational Fluid Dynamics (CFD) simulation of the cardiovascular system is increasingly becoming important and its application in everyday medical practice can already be envisaged. The goal of this workshop is to address all the factors involved in the development of a computational framework/software for modelling and analyses of the cardiovascular system and provide examples. The development of such framework, requires integration, management and interpretation of data from several technology areas such as a) feature detection and extraction of arterial geometry from imaging data, b) adaptive grid generation techniques for 3-D asymmetric geometries c) hemodynamic modelling, disparate length-scale model, and fluid-tissue interaction with high-performance computing, d) CFD data validation, e) feature extraction/detection and visualisation algorithms, f) graphical user interface to allow remote visualisation of post processed data. These computational tools are employed to study flow in specific problem sites in the vascular tree such as the carotid, femoral, coronary and abdominal arteries. Such studies provide understanding of the factors involved in the initialisation and evolution of arterial disease due to altered flow conditions (as a result of plaque formation) such as flow separation and reversal, and low and oscillatory wall shear stress. It is also used to study the effect of various clinical procedures such as the implantation of stents, vascular grafts, vascular prostheses and artificial valve implants on local and global hemodynamics. This workshop will address a new emerging paradigm in clinical practice known as predictive medicine for effective surgical planning and post surgical rehabilitation. The workshop will also address the difficulties in the implementation of some of the technology areas in this application with examples of carotid, femoral, and abdominal artery simulations.
Effects of oral Lactobacillus GG on enteric microflora in low-birth-weight neonates.
BACKGROUND: Colonization patterns, especially by anaerobic flora, may play an important role in neonatal gut function. Probiotics could affect disease risk either directly through colonization or indirectly by promoting changes in gut microbial ecology. METHODS: To study the ability of Lactobacillus GG(LGG) to colonize the neonatal gut and modify its microbial ecology, a prospective, randomized study was performed in 71 preterm infants of less than 2000 g birth weight. Infants less than 1500 g (24 treated, 15 control) received 10(9) LGG orally twice daily for 21 days. Those infants weighing 1500 to 1999 g (23 treated, 9 control) were treated for 8 days. Stools were collected before treatment and on day 7 to 8 (and day 14 and 21, in the infants weighing less than 1500 g) for quantitative aerobic and anaerobic cultures. RESULTS: Colonization with LGG occurred in 5 of 24 (21%) infants who weighed less than 1500 g versus 11 of 23 (47%) in larger infants. Colonization was limited to infants who were not on antibiotics within 7 days of treatment with LGG. There was a paucity of bacterial species at baseline, although larger infants had more bacterial species (1.59 +/- 0.13 (SEM) vs 1.11 +/- 0.12; P < 0.03) and higher mean log colony forming units (CFU) (8.79 +/- 0.43 vs 7.22 +/- 0.63; P < 0.05) compared with infants weighing less than 1500 g LGG. Treatment in infants weighing less than 1500 g resulted in a significant increase in species number by day 7, with further increases by day 21. This increase was mainly the result of increased Gram (+) and anaerobic species. No difference in species number was noted in controls. Mean log CFU of Gram (-) bacteria did not change in treated infants weighing less than 1500 g. However, Gram (+) mean log CFU showed a significant increase on day 21 (6.1 +/- 0.9) compared with day 0 (3.5 +/- 0.9) (P < 0.05). No significant changes in species number or quantitative counts were noted after LGG treatment in the infants weighing 1500 to 1999 g LGG was well tolerated in all infants. CONCLUSION: The neonatal response to a probiotic preparation is dependent on gestational and post-natal age and prior antibiotic exposure. Although LGG is a relatively poor colonizer in infants, especially those infants weighing less than 1500 g at birth, it does appear to affect neonatal intestinal colonization patterns.
Retinopathy of prematurity.
With improving survival of very low birth infants in India, Retinopathy of Prematurity (ROP is likely to emerge as a significant problem. The most important risk factor in the pathogenesis of ROP is prematurity. Other factors like frequent blood transfusions; sepsis, apnea and problems with oxygenation have also been implicated in the causation of ROP. Essentially asymptomatic in the initial stages, a good screening program is essential for the early detection and treatment of this condition. Description of the various stages and threshold ROP has been included in the protocol. Guidelines regarding the procedure of dilatation, ophthalmic examination and treatment (if required) has been provided in the protocols. Close cooperation between the ophthalmologist and neonatologist is essential for a successful program.
Congenital airway abnormalities in neonates.
Airway malformations such as laryngeal atresia, tracheal agenesis and subglottic stenosis are rare and present at birth with significant respiratory distress with or without stridor. There may be an initial improvement on bag and mask ventilation. Repeated attempts at intubation are met with failure. The related embryology and clinical aspect of airway malformations have been discussed. The prognosis in tracheal agenesis is universally fatal but cases with laryngeal atresia and subglottic stenosis may be saved with prompt tracheostomy and later surgical reconstruction.
Dandy-Walker malformation in Rubinstein-Taybi syndrome: a rare association.
A female infant is described with the rare association of Dandy-Walker malformation in Rubinstein-Taybi syndrome.
Unconjugated hyperbilirubinemia in newborns: current perspective.
Explore the source record for details and available documents.
Early neonatal hyperbilirubinemia using first day serum bilirubin level.
OBJECTIVE: To evaluate the predictive value of total serum bilirubin (TSB) < or =6 mg/dl at 24 +/- 6 hr postnatal age in identifying near term and term infants, who do not develop hyperbilirubinemia subsequently. DESIGN: Prospective study. SETTING: Tertiary care hospital. METHODS: All healthy neonates with gestation > or =35 weeks, in absence of significant illness or Rh hemolysis were included. TSB was estimated at 24 +/- 6 hr by micromethod using spectrophotometry. Infants were followed up clinically every 12 hr till discharge and then after 48 hr. TSB level was estimated again whenever clinical suspicion of jaundice exceeded 10 mg/dl. Primary outcome was defined as presence of hyperbilirubinemia (TSB > or= 17 mg/dl) till day five of age. RESULTS: Of the 220 infants, 213 (96.8%) were followed up. All infants were exclusively breastfed. Mean age at bilirubin estimation was 24.7 +/- 1.9 hr with mean TSB of 5.9 +/- 1.8 mg/dl. Clinically detectable jaundice was present in 164 (77%) and hyperbilirubinemia occurred in 22 (10.3%) infants. A TSB level of < or = 6 mg/dl at 24 +/- 6 hr was present in 136 (63.8%) infants and only one infant developed hyperbilirubinemia subsequently (probability < 1%). In the remaining 77 (36.1%) infants, with TSB >6 mg/dl, subsequent hyperbilirubinemia developed in 21 (27.2%) (sensitivity 95%, specificity 70.6%, positive predictive value 27.2%, negative predictive value 99.3%, likelihood ratio of positive test 3.23 and likelihood ratio of negative test 0.07). Babies with TSB levels higher than 6 mg/dl had a significant risk of developing hyperbilirubinemia (relative risk 38; 95% confidence interval 6-1675). CONCLUSION: A TSB level of < or = 6 mg/dl at 24 +/- 6 hr of life predicted neonates who would not develop hyperbilirubinemia.