PubMed Health⌕ Search

Biomedical subjects

A Butt

Publications and source records attributed to A Butt.

29 records · Page 2Linked to original sources

Clinical efficacy of lorazepam in prophylaxis of anticipatory, acute, and delayed nausea and vomiting induced by high doses of cisplatin. A prospective randomized trial.

Nausea and vomiting are extremely common and most distressing side effects of high-dose cisplatin therapy. Cisplatin induces anticipatory and acute, as well as, delayed emesis. High doses of metoclopramide can effectively decrease the intensity of these symptoms in up to 70% of cases. Several agents, including dexamethasone and antihistamines have been demonstrated to either increase the efficacy of metoclopramide or decrease the side effects. Lorazepam, a benzodiazepine, has both antiemetic and anxiolytic properties. It can be useful as an adjunct to metoclopramide-based therapy. We conducted a randomized trial to evaluate the efficacy of lorazepam in managing anticipatory, acute, and delayed emesis induced by high doses of cisplatin. A total of 180 events involving cisplatin administration (100 mg/m2 as a 24-hour continuous infusion) were randomized to receive metoclopramide along with dexamethasone and clemastine with and without lorazepam. Categorical scales were utilized to document the incidence of nausea and vomiting and side effects related to antiemetic therapy. All episodes are evaluable. Lorazepam significantly reduced the incidence of anticipatory nausea and vomiting (P < .05) as well as acute emesis (P = .05) induced by cisplatin. Delayed emesis was also decreased; however, it was statistically significant on day 3 only (P < .05). Side effects were few except for mild sedation and amnesia, which were significantly more common in those receiving lorazepam (P < .001). We conclude that lorazepam increases the efficacy of metoclopramide against cisplatin-induced anticipatory, acute, and delayed nausea and vomiting. This four-drug regimen may offer one of the best combinations to be utilized in comparative trials against the newly introduced serotonin antagonists.

Adult↗

Regulatory responses of the coxal organs and the anal excretory system to dehydration and feeding in the spider Porrhothele antipodiana (Mygalomorpha: Dipluridae)

The roles of coxal and anal excretion in the regulation of haemolymph osmolality, [Na+] and [K+] were studied in the mygalomorph spider Porrhothele antipodiana (mass 0.7&shy;1.0 g) under differing conditions of feeding and hydration state. Dehydration of starved spiders by removal of drinking water caused progressive mass loss at a rate of about 2.5 % of initial body mass per day and was associated with increases in the whole-body [Na+] and [K+] and in the osmolality, [Na+] and [K+] of the haemolymph. On provision of prey, feeding partially restored this mass loss but further elevated body and haemolymph ion concentrations. Dehydration reduced fluid excretion by the anal excretory system and the four coxal organs in both starved and feeding spiders. Starved hydrated spiders initially produced anal urine at 5 &micro;l day-1 and this was progressively reduced to zero after 4 days of water deprivation. Spiders dehydrated to less than 12 % mass loss would nevertheless feed and this initiated a small post-prandial anal diuresis (<5 &micro;l day-1 compared with >30 &micro;l day-1 in fed hydrated spiders). Coxal fluid was produced by dehydrated spiders only during feeding and was delivered into the prey, the rate of production by single organs decreasing from about 19 &micro;l h-1 g-1 body mass in hydrated spiders to about 4 &micro;l h-1 g-1 body mass in spiders dehydrated to 11 % mass loss. There was an increase in urine [K+] and in the rate of anal K+ excretion associated with ad libitum feeding in dehydrated spiders. However, urine [Na+] and the rate of anal excretion of Na+ were not increased by feeding. This was associated with an increase in [K+] of the stercoral fluid above that observed in either fed or starved hydrated spiders, but no significant change in [Na+]. Conversely, [Na+] of the coxal fluid produced during feeding was increased by dehydration whereas [K+] was not. These observations are consistent with the previously postulated roles of the coxal organs (Na+) and anal system (K+) in the excretion of ions ingested with the prey. Full elimination of the prey ions was accomplished only after drinking water was resupplied, which initiated further anal and coxal diureses. Smaller anal and coxal diureses also occurred on rehydration of unfed spiders. The production of coxal fluid in the absence of prey is further evidence that the coxal organs have a true excretory function besides, presumably, assisting ingestion. During dehydration and feeding, P. antipodiana, unlike many insects, is unable simultaneously to conserve water and to eliminate ions by production of a highly concentrated excretory fluid. Both coxal fluid and anal urine were approximately iso-osmotic to the haemolymph and the urine was markedly hypo-ionic.

Journal Article↗

Streptococcus associated toxic shock.

In the past few years, there appears to have been a change in the spectrum of disease caused by group A beta-haemolytic streptococcus (GABHS), and a toxic shock-like syndrome caused by this organism has recently been described in adults. We report four children with an acute illness characterised by rapid progression of shock, erythematous rash, multisystem organ involvement, electrolyte derangements, and desquamation who fulfil the previously established diagnostic criteria for toxic shock syndrome. Three of the children had extensive cutaneous and soft tissue infection and the fourth had peritonitis. All four developed bacteraemia. Treatment included aggressive cardiovascular resuscitation and antibiotic therapy. Although no patient died, they suffered multiple and severe complications requiring prolonged treatment and hospitalisation. Streptococcal toxic shock syndrome is a separate and clearly defined entity occurring in previously healthy children.

Cardiopulmonary Resuscitation↗

Serum myoglobin in myocardial infarction: the "staccato phenomenon." Is acute myocardial infarction in man an intermittent event?

When serum was sampled frequently and soon after acute myocardial infarction, myoglobinemia was extremely common, occurring in 12 of 13 selected patients. Myoglobin first appeared in the serum within a few hours after infarction, but not consistently earlier than creatine phosphokinase. The peak level of serum myoglobin was reached appreciably earlier than the peak values of serum creatine phosphokinase activity. Time of earliest myoglobin appearance in the serum, peak level of myoglobin measured, and duration of detectable myoglobin release all correlated poorly with clinical and biochemical estimates of severity of myocardial infarction. There was no correlation between myoglobin levels and infarct size as estimated from creatine phosphokinase kinetics. Myoglobin appeared in the serum in multiple short "staccato" bursts, or episodes, often lasting only one to two hours. The hypothesis is suggested that the pattern of myoglobin appearance is a reflection of the episodic nature of acute myocardial infarction. Although isolated myoglobin determination may not be useful at present, for quantification of total myocardial damage, its pattern of release may be a sensitive marker for studying the time course of infarction, and may be useful to evaluate therapeutic interventions designed to interrupt an ongoing syndrome of myocardial necrosis.

Acute Disease↗

Surface matching of multimodality image volumes by a fuzzy elastic registration technique.

Multimodality image registration is useful in diagnostic imaging and treatment planning for radiation therapy. In this paper, we present a technique which registers the surfaces of two volumes acquired by different medical imaging modalities. We represent the image volumes in terms of their surface elements known as tiles. We identify the fuzzy variables, assign fuzzy membership functions to them and generate a fuzzy rule database. The fuzzy algorithm reduces the discrepancy between the two set of tiles until the surfaces are matched. In order to study the efficacy of our approach, we severely warp a simulated image and register it with its original. We register CT and MR volumes of humanoid phantom images. Finally, we present the results at the end of the article.

Algorithms↗

Chordae tendineae rupture resulting in pulmonary edema in a patient with discrete subvalvular aortic stenosis--a case report and literature review.

This report concerns an apparently healthy elderly woman who presented with gradually worsening mitral regurgitation secondary to chordae tendineae rupture leading to pulmonary edema in the presence of discrete subvalvular aortic stenosis with a severe gradient reflecting the left ventricular outflow tract obstruction. The gradual worsening of heart failure took place parallel to the increase in severity of mitral regurgitation in a short period. The patient underwent successful mitral valve replacement with myectomy. Surgical inspection revealed rupture of the chordae tendineae to the posterior leaflets without any significant primary intrinsic disease of the mitral valve. The predominant mechanism of chordae tendineae rupture in this patient with discrete subvalvular aortic stenosis is a severe pressure gradient. It is suggested that increased awareness of chordae tendineae rupture as a cause of mitral regurgitation and the prompt use of appropriate diagnostic tools may facilitate the timely recognition of this potentially fatal, but treatable, cause of mitral regurgitation in patients with left ventricular outflow tract obstruction.

Aged↗