A comparative study of preoperative and postoperative changes in corneal astigmatism after pterygium excision by different techniques

Purpose: To study the changes in corneal astigmatism before and after pterygium excision as well as with differences between various surgical techniques (bare sclera, conjunctival autograft, amniotic membrane graft). Methods: The study population included 71 patients with primary pterygium who underwent surgery. The surgical techniques used differed among the study population. All the patients were preoperatively assessed for visual acuity, anterior and posterior segments, autorefraction, and autokeratometry. After surgery, the patients were assessed for visual acuity, autorefraction, and autokeratometry on day 5, 1 month, and 3 months and the results were analyzed. Paired and unpaired t-tests were used to compare the variables. The probability level of 0.05 was considered as statistically significant. Results: The reduction in the mean preoperative astigmatism of 3.47 ± 1.74 Diopters (D) to 1.10 ± 0.78 D 3 months after surgery was statistically significant (P < 0.0001). Bare sclera, conjunctival autograft, and amniotic membrane graft techniques exhibited changes in astigmatism amounting to 1.85 ± 0.88 D, 2.55 ± 1.26 D, and 2.67 ± 1.44 D, respectively. Pterygium excision surgeries using amniotic membrane graft and conjunctival autograft techniques were more effective than pterygium excision surgery using bare sclera technique in reducing astigmatism. Conclusion: Pterygium excision results in significant reduction in astigmatism which leads to improvement in visual acuity. Amniotic membrane graft and conjunctival autograft are better surgical techniques than bare sclera as far as reducing astigmatism is concerned.

Knowledge, attitude and practice of emergency contraceptive pills among tertiary level students in Trinidad: a cross-sectional survey / Conocimientos, actitudes y práctica de las píldoras anticonceptivas de emergencia entre estudiantes de nivel terciario en Trinidad: un estudio transversal

OBJECTIVE: The objective of this study was to estimate the general knowledge, attitude and practice of Emergency Contraceptive pills (ECs) among tertiary level students in Trinidad. METHOD: A 32-item questionnaire was constructed to assess knowledge, attitudes and practice of EC. There were 76 medical and 160 non-medical students who volunteered to fill-up the questionnaire. This survey was conducted by graduate students under supervision of the Department of Mathematics and Computer Science, UWI, St Augustine. RESULTS: Eighty-four per cent of the students were less than 25 years of age, 64% were Christians and 92% were single. Sixty-three per cent were female and there were more females in the non-medical group than the medical students group but the numbers were not significant. Eighty-one per cent used condoms as the main type ofcontraception. Only 63% had heard of ECs before and only 9% had heard of ECs from medical sources. Among the factors that related to attitude towards EC, only two factors were significant. Sixty-two per cent of students felt that increased EC use would increase promiscuity (p = 0.013) but 59% also felt that ECs should be made more easily available (p = 0.014). CONCLUSION: The general level of their knowledge about ECs was poor. The general attitude of students towards ECs was positive. This study will help policy-makers by providing evidence-based knowledge to promote EC use among university students.

OBJETIVO: El objetivo de este estudio fue evaluar de manera general los conocimientos, actitudes y prácticas en relación con las píldoras anticonceptivas de emergencia (PAE) entre estudiantes de nivel terciario en Trinidad. MÉTODO: Se diseñó una encuesta de 32 puntos con el propósito de evaluar los conocimientos, actitudes y prácticas de la anticoncepción de emergencia (AE). Hubo 76 estudiantes de medicina y 160 de otras carreras que se ofrecieron voluntariamente para responder la encuesta. RESULTADOS: El 84 por ciento de los estudiantes tenían menos de 25 años de edad, el 64% eran cristianos, y el 92% eran solteros. El 63 por ciento eran hembras y había más hembras en el grupo de estudiantes no médicos que en el grupo de estudiantes de medicina, pero las cifras no fueron significativas. El 81 por ciento usaban condones como tipo principal de contracepción. Solamente un 63% había oído de las PAEs y sólo el 9% había oído de las PAEs a partir de fuentes médicas. Entre los factores relacionados con las actitudes hacia las PAEs, sólo dos factores fueron significativos. El 62 por ciento de los estudiantes sentían que un aumento en el uso de la AE equivaldría a un aumento de la promiscuidad (p = 0.013), pero el 59% también tenía la percepción de que las PAEs debían estar más fácilmente al alcance de todos (p = 0.014). CONCLUSIÓN: En términos generales, el nivel de los conocimientos de los estudiantes sobre las PAEs fue en términos generales pobre, Su actitud general hacia las PAEs fue positiva. Este estudio ayudará a quienes tienen a su cargo el trazar políticas, brindándole conocimientos basados en evidencias, a promover el uso de PAEs entre los estudiantes universitarios.

Anti-seizure efficacy of nimodipine in pentylenetetrazole and kainic acid combined seizure models in mice.

The present study aimed at establishing two models of experimental seizures by combination treatment with subconvulsive doses of PTZ and kainic acid in adult male mice and evaluating the modulatory role of cerebroselective dihydropyridine calcium channel blocker, nimodipine. The CD50 +/- SEM value for PTZ was found to be 20.00 +/- 0.92 mg/kg, ip in kainic acid (administered at per se subconvulsive dose of 1.00 mg/kg, ip) pretreated mice while CD50 +/- SEM value for kainic acid was found to be 0.30 +/- 0.08 mg/kg, ip in PTZ (administered at per se subconvulsive dose of 30.00 mg/kg, ip) pretreated mice. Nimodipine (5.00 mg/kg, ip) significantly protected the mice from seizure in both of the combination in vivo seizure models. The results suggested synergistic interaction between PTZ and kainic acid at subconvulsive dose combination while the protective efficacy of nimodipine suggested the role of calcium ion as an important mediator for the genesis of seizures.

Rational use of anti-snake venom (ASV): trial of various regimens in hemotoxic snake envenomation.

BACKGROUND: Viperine snake bites cause hemotoxicity in the form of coagulation dysfunction. Optimal dose requirement of anti-snake venom (ASV) and duration of therapy in such situation have not yet been fully explored. Our aim in this study was to compare two low-dose continuous infusion regimes with the standard high dose intermittent bolus regime in treating systemic envenomation and preventing its recurrence. METHODS: A prospective interventional study was conducted on 90 adult patients with snake bite with hemotoxicity. Patents were allocated into three treatment regimes, each regime being tried on 30 patients. Regimen I (standard high dose regimen) consisted of conventional, intermittent bolus dosage of 100 ml of ASV as a loading dose followed by 50 ml every six hours till whole blood coagulation time (CT) became normal. Regimen II consisted of 30 ml of ASV as a loading dose followed by 30 ml continuous infusion every six hours till two CTs at an interval of six hours were normal and a further dose of 30ml over 24 hours. Regimen III was similar to Regimen II in all aspects except that loading dose was 70 ml (instead of 30 ml). RESULTS: In patients with mild envenomation, even though the average requirement of ASV was only marginally lower in Regimen II (128.6 ml) as compared to in Regimen I (137.5 ml), one patient on Regimen I had relapse of coagulation dysfunction. In patients with moderate envenomation, average requirement of ASV was 221.3 ml and 179 ml in Regimens II and III respectively, which was much less than in Regimen I (343.8 ml) (p values 0.05 and 0.01 respectively). Further, no patient receiving Regimen III had relapse of coagulation dysfunction. In severe envenomation, average dose of ASV required was almost similar in Regimens II and III, i.e., 213.7 ml and 233.7 ml respectively, as compared to 433.3 ml required in Regimen I (p values 0.02 and 0.001 respectively). However, time lapse for CT normalization was only 18 hours in Regimen III as compared to 23.6 hours and 24 hours in Regimens I and II respectively. CONCLUSION: Regimens consisting of continuous intravenous infusion of ASV i.e., Regimen II in mild envenomation and Regimen III in moderate and severe envenomation are likely to make significant saving of ASV and reduction of recurrence of coagulation dysfunction.

Dose and frequency of anti-snake venom injection in treatment of Echis carinatus (saw-scaled viper) bite.

OBJECTIVES: To assess the adequacy of initial standard dose of 100 ml of polyvalent anti-snake venom (ASV) and subsequent doses of 50 ml in correcting coagulation dysfunction in cases of viperine bite and to find the incidence of recurrence of coagulation dysfunction. The other objective was to correlate total requirement of ASV with initial coagulation profile. METHODS: Forty two adult patients of Echis carinatus bite with features of systemic envenomation, admitted over a period of 18 months, were monitored every six hours with bed-side clotting time (CT) and were given an initial standard dose of 100 ml of ASV intravenously. Further doses of 50 ml were administered six hourly until coagulation profile normalised or whenever a recurrence of coagulation dysfunction observed. RESULTS: Twenty one (50%) of 42 patients who received initial standard dose of 100 ml of ASV required a subsequent 50 ml of ASV. Ten (23.8%) of them required a further 50 ml on subsequent test (making the total requirement at least 200 ml). Sixteen (72.7%) of 22 patients who had incoagulable blood at entry required further dose of anti-snake venom (after initial 100 ml), six required 150 ml and ten 200 ml or more before CT returned to normal. Recurrence of venom antigenemia as evidenced by prolonged clotting time was noticed in 15 patients (35.7%). The mean dose requirement of anti-snake venom was 179.2 ml. CONCLUSIONS: Total requirement of anti-snake venom correlated positively with degree of coagulation dysfunction at entry. Hence patients having incoagulable blood at entry should be administered higher initial dose of ASV i.e., 150-200 ml. If needed as judged by CT, subsequent dose of ASV in patients having still incoagulable blood should be 100 ml (and those having mild dysfunction 50 ml) until total correction occurs Recurrence of coagulation dysfunction was observed in approximately one-third of patients and thus, CT should be monitored even after total correction.

A trial of various regimens of antibiotics in acute appendicitis.

A three year prospective randomised study was undertaken to study the efficacy of three regimens of antimicrobial drug combinations in reducing postoperative wound sepsis in acute appendicitis. Group A--Metronidazole and gentamicin; Group B--Metronidazole and ciprofloxacin; Group C--Metronidazole and cefotaxime. Randomization was done by drawing from a set of sealed envelopes. Antibiotics were started preoperatively once a presumptive diagnosis of appendicitis was made, provided there was no history of prior antibiotic usage. For simple appendicitis (normal or inflamed) two more doses were given postoperatively. For complicated appendicitis, duration of antibiotic treatment was four days postoperatively. All antibiotics were given intravenously to avoid variations in bioavailability. Wound was inspected daily till discharge and at 30 days post operatively or earlier if the patient had symptoms of wound infection. A total of 128 patients completed the study. Eighty nine were simple appendicitis while the rest were complicated. Twenty one developed wound infection. Out of 21, 13 occurred in group A, 5 in group B and 3 in group C. Individually, the difference in infection rates between group A and group C patients with simple appendicitis was statistically significant. Infection rates in all other groups were not statistically different. Cefotaxime and metronidazole combination had the lowest wound infection rate. Hence it is recommended for antibiotic prophylaxis.

Effect of indoor air pollution on the respiratory system of women using different fuels for cooking in an urban slum of Pondicherry.

BACKGROUND. Some of the highest exposures to air pollutants in developing countries occur inside homes where biofuels are used for daily cooking. Inhalation of these pollutants may cause deleterious effects on health. We studied the effects of exposure to indoor air pollution from the use of cooking fuels on lung functions and respiratory symptoms in women aged 15-60 years. METHODS. The study was conducted in Kuruchikuppam, an urban slum in Pondicherry. The study participants were 105 women using biofuels, 105 using kerosene and 105 using liquid petroleum gas (LPG), selected from among 1117 women aged 15-60 years, by a stratified random sampling technique. These women were interviewed at home to collect information about exposure to fuel smoke and presence of respiratory symptoms. Lung functions were assessed by measuring forced vital capacity (FVC), forced expiratory volume in the first second (FEV1) and peak expiratory flow rate (PEFR). Occurrence of respiratory symptoms over six months was noted by making monthly follow up visits. RESULTS. Women using biofuels experienced more respiratory symptoms (23%) than those using kerosene (13%;p > 0.05) or LPG (8%; p < 0.05). Lung functions-FVC, FEV1, FEV1% and PEFR-were significantly lower in biofuel users compared with both kerosene (p < 0.01) and LPG users (p < 0.001). Lung functions in kerosene users also were significantly poorer when compared with LPG users (p < 0.01). Predicted pulmonary functions using multiple regression equations, derived from the data set of the present study, indicated that women using biofuels were more liable to have reduced pulmonary functions than women using kerosene or LPG. CONCLUSION. Women exposed to biofuel smoke suffer more from respiratory illnesses and have decreased pulmonary functions compared with women exposed to kerosene or LPG smoke. To reduce pollutant exposures we recommend the use of smokeless chullas or cleaner fuels such as charcoal, biogas and kerosene.

Truncal vagotomy and gastrojejunostomy for chronic duodenal ulcer in India.

BACKGROUND: Insufficient information is available on long term results of truncal vagotomy and gastrojejunostomy since most previous series have relied on functional grading using the Visick scale which possibly both overdiagnoses and underdiagnoses complications. We used endoscopy to assess the results following truncal vagotomy and gastrojejunostomy as well as functional grading and compared them with published results of highly selective vagotomy. METHODS: Two hundred patients were reviewed (5-11 years after truncal vagotomy and gastrojejunostomy) by clinical examination and endoscopy. Completeness of vagotomy was assessed by estimation of the postprandial alkaline tide in the urine and gall bladder using ultrasonography. RESULTS: The ulcer recurrence rate was 15 (7%). Nine (60%) of the recurrent ulcers were asymptomatic and detected only on endoscopy. In all patients with recurrence, the urinary alkaline tide estimation revealed an incomplete vagotomy. Dumping was present in 12%, it was troublesome in 4%, occasional episodes of post-vagotomy diarrhoea in 6% (all in Visick grades I or II) and bile vomiting in 17% (affecting the lifestyle in only 5%). Recurrence and other complications were not related to the experience of the operating surgeon or the type of gastroenterostomy. There was no mortality. Overall, satisfactory long term functional results (Visick grades I and II) were found in 8% of patients. CONCLUSIONS: Truncal vagotomy and gastrojejunostomy still remains the best option in the surgical management of chronic duodenal ulcer. Long term results are good with a relatively low incidence of troublesome complications.

Atrial natriuretic peptide: pathophysiological considerations.

Atrial natriuretic peptide (ANP) is a cardiac hormone with potent diuretic and natriuretic properties. This hormone mediates a finely tuned control mechanism for the maintenance of blood pressure and volume. The altered pressure and volume in many important cardiovascular diseases suggest that understanding the functional role of ANP is integral to these conditions. ANP levels are increased in a wide variety of cardiac disorders such as hypertension, diabetes, congestive heart failure, myocardial infarction and valvular heart diseases. Several studies have indicated a positive correlation between the severity of cardiac disorders and plasma ANP levels highlighting its importance as a prognostic factor in cardiovascular diseases. Furthermore, its compensatory role in these situations has prompted a world-wide investigation on the use of ANP as a drug in cardiac diseases and it is not surprising that there has been a wealth of scientific papers on this subject. This review attempts to summarize the present knowledge concerning the physiology of ANP and evaluates some of the latest experimental findings and opinions on the involvement of ANP in cardiovascular diseases.

Macular dazzling test in central serous retinopathy using electronic flash.

Recovery time after dazzling the macula by conventional electronic flash used by the photographer instead of the light of an ophthalmoscope was recorded in 100 normal subjects and 50 cases of active central serous retinopathy. In normal subjects the recovery time after macular dazzling test was 10 to 54 seconds. There was no difference in value between the two sexes. The recovery value increases with the advancement of age. The recovery time was 10 to 15 minutes in cases of active central serous retinopathy and there was no delay in recovery time in healed central serous retinopathy. The values elicited by electronic flash were repeatable in comparison to the technique of dazzling the macula by light of an ophthalmoscope.