Biomedical subjects

N Bhatta

Publications and source records attributed to N Bhatta.

7 recordsLinked to original sources

PubMed2002

Air travel and supplemental oxygen therapy in patients with cardiopulmonary diseases.

Air travel has become more popular in modern society and increasing number of patients with cardiopulmonary diseases are travelling by air. Although it represents a safe form of transportation, it leads to significant stress to an individual and its certain inherent risks may cause or promote hypoxia in patients with cardiopulmonary diseases. Clinicians will have to deal with situations where they will be asked to assess the fitness to travel and need for supplemental oxygen during flight. Once in a while the clinician may be required to help a co-passenger in distress during air travel. Predicting requirement of supplemental oxygen during commercial air flight requires knowledge of physiology of commercial air flight and available prediction equations. With modern pressurized aircrafts most of the patients with cardiopulmonary diseases would be able travel by air safely.

Altitude↗

PubMed1999

Clinical and laboratory study of kala-azar in children in Nepal.

Reports are scanty regarding kala-azar in children in Nepal. In this communication we document 20 children diagnosed to have kala-azar who were admitted and treated at B. P. Koirala Institute of Health Sciences, Dharan, Nepal. The children were between 2 and 14 years old. The duration of illness varied between 12 days and 24 months with a majority (65 per cent) of children being ill for less than 6 months. Hepatomegaly and splenomegaly were seen in 95 and 90 per cent of cases respectively. Splenomegaly was not found in two (10 per cent) children. Anaemia, leucopenia, and thrombocytopenia were seen in 95, 60, and 75 per cent of children respectively. Amastigotes of Leishmania donovani (LD bodies) were demonstrated in Giemsa-stained smears of bone marrow aspirates in 16 (80 per cent) children. All the children responded to treatment with sodium stibogluconate. No mortality was observed. This study emphasizes the importance of kala-azar in children in endemic areas of eastern Nepal.

Adolescent↗

PubMed1994

Comparative study of different laser systems.

OBJECTIVE: To review lasers, laser physics, laser-tissue interaction, delivery systems, and their clinical applications relevant to gynecology. SETTINGS: Gynecological Service at Massachusetts General Hospital (MGH) and MGH Laser Center. INTERVENTIONS: None. DESIGN: Laser literature review and personal experiences of the authors were used to prepare this manuscript. CONCLUSIONS: Lasers have been used in gynecologic practice for cutting and coagulating purposes. Photodynamic therapy has been used clinically for malignant conditions and is being investigated for dysplastic lesions of the lower genital tract and for endometrial ablation. Laser welding has potential, but further work is required in this field before it finds a clinical application. The main lasers used in gynecology are CO2, neodymium-yttrium aluminum garnet (Nd:YAG), and potassium tatanyl-phosphate-doubled Nd:YAG. Pulsed Ho:YAG laser looks promising, as does diode lasers. Holmium-yttrium aluminum garnet and diode lasers will be soon available commercially. Improvements in delivery systems have increased user friendliness, and more developments in this area are anticipated, for example, a fiber-optic delivery system for CO2 lasers. We believe that enhanced understanding of laser technology will provide unique applications for development in gynecology.

Female↗

PubMed1993

Injury and adhesion formation following ovarian wedge resection with different thermal surgical modalities.

The purpose of this study is to determine the role of bleeding, acute thermal damage, and charring in adhesion formation. Postoperative adhesions were compared following ovarian wedge resection in 48 rabbits using different lasers, electrosurgery, and scalpel. Twelve ovaries were sectioned per modality, in randomized pairs. Acute thermal injury as assessed by histology, bleeding, and charring differed among the modalities used. Adhesions were assessed 4 weeks later, by an investigator completely blinded of the treatment protocol. The adhesion scores were 11.6 +/- 8.0 with pulsed Er:YAG laser; 11.9 +/- 7.5 with scalpel; 8.3 +/- 9.3 with electrocautery; 6.7 +/- 8.8 with a continuous (c.w.) Nd:YAG laser; 5.3 +/- 4.8 with c.w. CO2 laser; 3.1 +/- 2.7 with pulsed CO2 laser; 1.7 +/- 1.8 with pulsed Ho:YAG laser; and 0.8 +/- 1.5 in the control (no resection) group. Ho:YAG, Nd:YAG, and electrocautery were completely hemostatic. Bleeding was minimal with the CO2 lasers. Er:YAG and scalpel caused maximum bleeding, requiring hemostatic measures to prevent exsanguination. Charring occurred with electrocautery, CO2 laser, and Nd:YAG laser. Bleeding and charring correlated with adhesion formation, but the histological depth of thermal damage did not. The Ho:YAG laser is a hemostatic, fiber-optic compatible laser causing significantly fewer adhesions (P < 0.04) than scalpel, electrocautery, Nd:YAG, Er:YAG, and c.w. CO2 lasers. Clinical use of the Ho:YAG laser, and the role of carbonization in promoting adhesions, deserve further study.

Adnexal Diseases↗

PubMed1992

Endometrial ablation by means of photodynamic therapy with photofrin II.

OBJECTIVE: Photodynamic therapy is a technique in which tissue is irradiated with light after the use of a photosensitizing drug that produces singlet oxygen, which has a cytotoxic effect. The feasibility of using photodynamic therapy with photofrin II for endometrial ablation was studied. STUDY DESIGN: Fifty-eight rabbits were studied. Preferential uptake of photofrin II by endometrial tissue, compared with the myometrium, was established by drug extraction and fluorescence microscopy after administration of photofrin II intravenously. Dosimetry for endometrial ablation was established by administering photofrin II in 1, 2, 5, and 10 mg/kg doses and laser light (630 nm) at radiant exposures of 100 and 200 J/cm2. Histologic examination was performed at 24 hours, 5 days, and 10 days after treatment. There were two control groups. One group received laser light but no photofrin II, and the other received photofrin II without laser light. RESULTS: The concentration of photofrin II was three times higher in the endometrium than in the myometrium at doses of 1 and 2 mg/kg. Fluorescence microscopy of frozen sections of endometrium and myometrium showed a predominantly perivascular fluorescence from photofrin II. A dose of 1 and 2 mg/kg and a flow of 100 J/cm2 was adequate for endometrial ablation in rabbits. At 24 hours after treatment there was extensive hemorrhage and evidence of cell death in the entire endometrium and mild hemorrhage in 10% to 50% of the inner circular layer of the myometrium. At 5 days after treatment necrosis of the entire endometrium and the inner half of the myometrium was seen, but the outer half of the myometrium and the serosa were normal. There were no cases of uterine perforation. Similar results were seen at 10 days after treatment, except for the additional presence of inflammatory cells. Neither control group (drug without light, light without drug) showed any injury to the endometrium at 24 hours. CONCLUSION: We conclude that endometrial ablation can be effectively achieved in rabbits by means of photodynamic therapy with photofrin II without significant complications.

Animals↗

PubMed1991

Variable tolerance of the developing follicle and corpus luteum to gonadotropin-releasing hormone antagonist-induced gonadotropin withdrawal in the human.

To examine the differential sensitivity of the ovary to temporary withdrawal of gonadotropin support at different stages of folliculogenesis and corpus luteum function, GnRH antagonist blockade of gonadotropin secretion was examined in 17 studies using the Nal-Glu GnRH antagonist. A vehicle control, antagonist treatment, and follow-up cycle format was used in each study. A previously determined ED100 dose of the Nal-Glu GnRH antagonist (150 micrograms/kg) or vehicle was administered sc every 24 h for 3 consecutive days in the midfollicular phase (MFP), late follicular phase (LFP), and midluteal phase (MLP). In studies in the MFP (n = 7), the largest follicle was 11 +/- 2 mm (mean +/- SEM), and the mean estradiol (E2) level was 220 +/- 44 pmol/L on the first day of antagonist administration. Administration of the antagonist resulted in a 75 +/- 6% suppression of LH (P less than 0.005), no significant change in FSH, and suppression of E2 to the assay detection limit (P less than 0.05). Total cycle length was increased compared to that of the vehicle control cycle (37.3 +/- 1.3 vs. 26.3 +/- 1.1 days; (P less than 0.005) due to prolongation of follicular phase length (P less than 0.005) and reinitiation of folliculogenesis. In the LFP (n = 5), the largest follicle was 16 +/- 1 mm (P less than 0.05 vs. MFP), and the E2 level was 394 +/- 95 pmol/L (P less than 0.05 vs. MFP) on the first day of antagonist administration. Antagonist administration resulted in a 65 +/- 6% suppression of LH (P less than 0.05), a 47 +/- 11% decrease in FSH (P less than 0.05), and no significant change in E2. Total cycle length was prolonged (32.4 +/- 2.2 vs. 25.6 +/- 0.4 days; P less than 0.05) due to an increase in follicular phase length (P less than 0.02); however, the prolongation of the follicular phase was significantly less than that of the MFP (8.0 +/- 1.5 vs. 15.1 +/- 0.1 days; P less than 0.001), suggesting ovulation from the initial dominant follicle. In studies in the MLP (n = 5), LH, E2, and progesterone decreased to the assay detection limit after antagonist administration, while FSH decreased by 36 +/- 4% (P less than 0.05). Menstrual bleeding occurred within 24-48 h of the final Nal-Glu antagonist injection.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMedDate not supplied

Roundworm infestation presenting as acute abdomen in four cases--sonographic diagnosis.

Infestation with Ascaris lumbricoides (roundworm) is very common in the tropics and subtropics. Patients with ascariasis can be asymptomatic or may present with different clinical features in the form of simple nausea, decreased appetite, abdominal pain or more severe bowel obstruction, perforation, intussusception, biliary colic etc. Ultrasonography (USG) can be quick, safe, noninvasive and relatively inexpensive tool in diagnosing the presence of worms and also evaluating response to treatment (1, 2, and 3). Here we present four cases of roundworm infestation presenting with acute abdomen in the emergency department, which were diagnosed by USG and further imaging features of ascariasis on USG is described.

Abdomen, Acute↗