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R Sequeira

Publications and source records attributed to R Sequeira.

13 recordsLinked to original sources
PubMed2005

Anticonvulsant therapy for status epilepticus.

BACKGROUND: Status epilepticus is a medical emergency associated with significant mortality and morbidity, which requires immediate and effective treatment. OBJECTIVES: (1) To determine whether a particular anticonvulsant is more effective or safer to use in status epilepticus compared to another and compared to placebo.(2) To delineate reasons for disagreement in the literature regarding recommended treatment regimens and to highlight areas for future research. SEARCH STRATEGY: We searched the following electronic databases using the highly sensitive search strategy for identifying published randomised controlled trials: (1) Cochrane Epilepsy Group Specialized Register (July 2005); (2) Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 2,2005); (3) MEDLINE (1966 - August 2004); (4) EMBASE (1966 - January 2003). SELECTION CRITERIA: Randomised controlled trials of participants with premonitory, early, established or refractory status epilepticus using a truly random or quasi-random allocation of treatments were included. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials for inclusion, assessed trial quality and extracted data. MAIN RESULTS: Eleven studies with 2017 participants were included. Few studies used the same interventions. Diazepam was better than placebo in reducing the risk of non-cessation of seizures (RR 0.73, 95% CI 0.57 to 0.92), requirement for ventilatory support (RR 0.39, 95% CI 0.16 to 0.94) or continuation of status epilepticus requiring use of a different drug or general anaesthesia (RR 0.73, 95% CI 0.57 to 0.92). Lorazepam was better than placebo for risk of non-cessation of seizures (RR 0.52, 95% CI 0.38 to 0.71) and for risk of continuation of status epilepticus requiring a different drug or general anaesthesia (RR 0.52, 95% CI 0.38 to 0.71). Lorazepam was better than diazepam for reducing risk of non-cessation of seizures (RR 0.64, 95% CI 0.45 to 0.90) and had a lower risk for continuation of status epilepticus requiring a different drug or general anaesthesia (RR 0.63, 95% CI 0.45 to 0.88). Lorazepam was better than phenytoin for risk of non-cessation of seizures (RR 0.62, 95% CI 0.45 to 0.86). Diazepam (30 mg intrarectal gel) was better than a lower dose (20 mg intrarectal gel) in premonitory status epilepticus for the risk of seizure continuation (RR 0.39, 95% CI 0.18 to 0.86). AUTHORS' CONCLUSIONS: Lorazepam is better than diazepam or phenytoin alone for cessation of seizures and carries a lower risk of continuation of status epilepticus requiring a different drug or general anaesthesia. Both lorazepam and diazepam are better than placebo for the same outcomes. In the treatment of premonitory seizures, diazepam 30 mg in an intrarectal gel is better than 20 mg for cessation of seizures without a statistically significant increase in adverse effects. Universally accepted definitions of premonitory, early, established and refractory status epilepticus are required.

Anticonvulsants↗
PubMed2002

Water-soluble aerosol and visibility degradation in Hong Kong during autumn and early winter, 1998.

During the October-December 1998 period, 30 daily samples of size-separated airborne respirable suspended particulates (RSP) were collected at the quasi-rural Kadoorie Agricultural Research Centre (KARC) in central New Territories (NT), Hong Kong, Special Administrative Region (SAR). Results of analysis indicate that sulphate is the predominant water-soluble species, and that sulphate, nitrate and ammonium together contribute to most of the total water-soluble fine aerosol mass. An interesting result obtained through principal component analysis (PCA) following varimax rotation of the bivariate correlation matrix for water-soluble species is that the first component (PCl) is made up exclusively of SO4 and NH4 ions. The stoichiometric ratio and correlation coefficient between the two ions suggest that ammoniated sulphate compounds are the probable species responsible for the PCI. Further, the use of a linear multivariate visibility model which accommodates the effect of relative humidity (RH) shows that SO4 and NH4 are the only anions important in visibility degradation. It is found that SO4 in aerosol at the KARC can be used to predict the visual range (or extinction coefficient) recorded from Kings Park, Kowloon, approximately 10 km away. This result suggests that SO4 (and possibly NH4) is, generally, likely to be of regional rather than of local origin. Further observations suggest that the model is most applicable to a moderate visual range, 10 km < R(v) < or = 20 km under a rather broad range of ambient relative humidity, 40% < RH < or = 80. However, this inference does not preclude the contributions to visibility degradation--mostly by absorption--by some of the water-insoluble aerosol constituents, including carbon, or the pollutant gas, NO2.

Aerosols↗
PubMed1999

Safeguarding production agriculture and natural ecosystems against biological terrorism. A U.S. Department of Agriculture emergency response framework.

Foreign pest introductions and outbreaks represent threats to agricultural productivity and ecosystems, and, thus, to the health and national security of the United States. It is advisable to identify relevant techniques and bring all appropriate strategies to bear on the problem of controlling accidentally and intentionally introduced pest outbreaks. Recent political shifts indicate that the U.S. may be at increased risk for biological terrorism. The existing emergency-response strategies of the Animal and Plant Health Inspection Services (APHIS) will evolve to expand activities in coordination with other emergency management agencies. APHIS will evolve its information superstructure to include extensive application of simulation models for forecasting, meteorological databases and analysis, systems analysis, geographic information systems, satellite image analysis, remote sensing, and the training of specialized cadres within the emergency-response framework capable of managing the necessary information processing and analysis. Finally, the threat of key pests ranked according to perceived risk will be assessed with mathematical models and "what-if" scenarios analyzed to determine impact and mitigation practices. An infrastructure will be maintained that periodically surveys ports and inland regions for the presence of exotic pest threats and will identify trend abnormalities. This survey and monitoring effort will include cooperation from industry groups, federal and state organizations, and academic institutions.

Agriculture↗
PubMed1996

Heart rate variability during the first 24 hours of successfully reperfused acute myocardial infarction: paradoxic decrease after reperfusion.

Heart rate variability (HRV) was evaluated during the first 24 hours of hospitalization in 36 patients with acute myocardial infarction. Reperfusion was achieved by 60 minutes in 21 patients (group M1) and by 130 minutes in the remaining 15 (group M2). Mean 24-hour HRV measures were not significantly different between groups M1 and M2. Hourly spectral analysis revealed a decrease in total power (0.01 to 1.0 Hz) from 0 to 8 hours to 9 to 16 and 17 to 24 hours in groups M1 (7.04 +/- 0.27 to 6.94 +/- 0.28 and 6.52 +/- 0.18; p = 0.0006) and in group M2 (6.88 +/- 0.30 to 6.57 +/- 0.23 and 6.40 +/- 0.15; p = 0.002). Total power decreased immediately after reperfusion: in group M1 it decreased during the second hour (7.32 +/- 0.96 to 6.42 +/- 1.2; p = 0.001) and in group M2 during the third (7.47 +/- 1.2 to 6.73 +/- 1.4; p = 0.049) and fourth hours (7.47 +/- 1.2 to 6.48 +/- 1.4; p = 0.029). Mean change in total power in the second hour was -11.6% in group M1 and +3.9% in group M2 (p = 0.0001) and in the third hour, +14.5% in group M1 and -8.6% in group M2 (p = 0.006). During the remaining 21 hours, there was no significant difference in hourly change in total power between groups. Similar changes were noted in high-frequency power, but the ratio of low-frequency to high-frequency power was unchanged. In acute myocardial infarction, HRV is higher during the early phase and decreases as hours progress. Reperfusion causes an immediate, transient, and seemingly paradoxic decrease in HRV, probably because of an abrupt decrease in parasympathetic tone.

Anistreplase↗
PubMed1995

Laparo-vaginal treatment of uterine procidentia.

The following is a description of a combined vaginal and laparoscopic repair of vaginal eversion with uterine prolapse (procidentia). There are few procedures that seek to correct the condition while preserving vaginal function. Among them are (1) vaginal approach for sacrospinous fixation, (2) abdominal sling procedures, and (3) abdominal and laparoscopic approaches for promontorial fixation. We are presenting a technical report of a modified sling procedure done via laparoscopy. This technique achieves the functional vaginal reconstruction and avoids the potentially dangerous bleeding associated with the sacral fixation. It has also been our experience that the sacrospinous fixation technique affords limited visual exposure, and henceforth the laparoscopic vaginal sling procedure may be a better alternative.

Female↗
PubMed1994

Credentialing physicians for new technology: the physician's learning curve must not harm the patient.

Laparoscopic Cholecystectomy (L.C.) offers advantages that are realized only when patient safety is assured. In November 1990, The Department of Surgery at The New York Hospital Medical Center of Queens initiated a program to introduce this new technology to surgeons who had not performed the operation previously. A preceptorship program was initiated, accompanied by contemporaneous quality assurance review. This is the experience of 15 general surgeons who performed their first 400 L.C.s from November 1990 through March 1993. There were no deaths and only one common bile duct injury (0.25%).

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1988

QRS morphology-dependent pharmacodynamics in multiform ventricular ectopic activity.

The effect of an infusion of intravenous procainamide on the frequency of ventricular premature complexes (VCPs) of differing QRS morphologies was studied in 20 patients with multiform ectopic activity. In 17 of 20 patients, there was differential suppression of single VPCs with different QRS morphologies. VPCs of the most frequent QRS morphology and the second most frequent QRS morphology were compared with respect to the procainamide level at the escape of VPCs from 85% suppression and the duration of suppression measured from the onset of the procainamide infusion. In 8 patients, VPCs of the most frequent QRS morphology remained suppressed at lower procainamide concentrations and for longer times than did VPCs of the second most frequent QRS morphology (escape procainamide concentration = 2.8 +/- 1.7 versus 5.4 +/- 2.3 micrograms/ml, p less than 0.025; time to escape 244 +/- 138 versus 98 +/- 114 min; p less than 0.05). In 9 other patients, VPCs of the second most frequent QRS morphology remained suppressed at lower procainamide concentrations and for longer times than did VPCs of the most frequent QRS morphology (escape procainamide concentration 2.9 +/- 1.4 versus 8.3 +/- 6.3 micrograms/ml, p less than 0.025; time to escape 317 +/- 114 versus 63 +/- 80 min; p less than 0.001). Thus, in individual patients there are specific patterns of suppression of VPCs of different QRS morphologies which are independent of the frequency of each morphology. There is apparently a differential pharmacologic effect of procainamide on the foci or pathways responsible for the different QRS morphologies of multiform VPCs.

Arrhythmias, Cardiac↗
PubMed1986

Procainamide pharmacokinetics in patients with acute myocardial infarction or congestive heart failure.

Abnormal procainamide pharmacokinetics (prolonged half-life and decreased volume of distribution) and pharmacodynamics (decreased threshold for the suppression of premature ventricular complexes) have been suggested in patients with acute myocardial infarction or congestive heart failure, or both. To better define procainamide kinetics, 37 patients in the acute care setting received intravenous procainamide (25 mg/min, median dose 750 mg) with peak and hourly blood samples taken over 6 hours. Compared with the 10 control patients, the 12 patients with acute myocardial infarction and the 15 patients with congestive heart failure had normal procainamide pharmacokinetics with respect to half-life (2.3 +/- 1.0, 2.5 +/- 0.9 and 2.6 +/- 0.8 hours, respectively), volume of distribution (1.9 +/- 0.7, 1.8 +/- 0.4 and 1.8 +/- 0.5 liters/kg, respectively), clearance (11.3 +/- 7.5, 9.3 +/- 3.6 and 9.1 +/- 3.5 ml/min per kg, respectively) and unbound drug fraction (66 +/- 9, 66 +/- 9 and 69 +/- 4%, respectively). Low thresholds for greater than 85% premature ventricular complex suppression were confirmed in these patients (median 4.7 micrograms/ml in patients with acute myocardial infarction and 3.3 micrograms/ml in patients with congestive heart failure). Thus, differences in the response of premature ventricular complexes to procainamide reflect electropharmacologic differences dependent on clinical setting rather than pharmacokinetic abnormalities. Furthermore, the reduction of procainamide dosing in patients with acute myocardial infarction or congestive heart failure, based solely on prior kinetic data, may result in inappropriate antiarrhythmic therapy.

Aged↗
PubMed1980

Pulsed Doppler echocardiographic findings in total anomalous pulmonary venous drainage to the coronary sinus.

The pulsed doppler echocardiographic (PDE) findings in a premature cyanotic infant with total anomalous pulmonary venous return to the coronary sinus are reported. Features that suggested the diagnosis of total anomalous pulmonary venous return were 1) an area of systolic-diastolic turbulent flow posterior to the apparent left atrial border, which was interpreted as representing the convergence of pulmonary venous return to a common pulmonary vein, and 2) systolic and diastolic turbulent flow within the right atrium suggesting pulmonary venous return through the coronary sinus. We suggest that PDE should be included as part of the evaluation of cyanotic infants in whom the diagnosis of total anomalous pulmonary venous return is considered.

Diagnosis, Differential↗