PubMed Health⌕ Search

Biomedical subjects

H Powell

Publications and source records attributed to H Powell.

At least 55 records · Page 3Linked to original sources
PubMed1994

Effects of extradural anaesthesia on interleukin-6 and acute phase response to surgery.

Serum concentrations of the cytokine, interleukin-6 (IL-6), increase after surgical trauma. IL-6 mediates the synthesis of acute phase proteins and stimulates secretion of pituitary hormones. We have examined the time course of circulating IL-6, and cortisol and growth hormone responses in patients undergoing hysterectomy to determine if IL-6 contributes to the early pituitary hormone changes found during surgery. One group (n = 8) received a standardized general anaesthetic while the remaining patients (n = 8) received extradural analgesia to T4-S5 in addition to a similar general anaesthetic. In the general anaesthesia group, there was a significant increase in serum cortisol and growth hormone concentrations before any changes in IL-6 were detected. Furthermore, in the extradural group, in whom these hormonal responses were attenuated, circulating IL-6 concentrations did not differ significantly from the general anaesthesia group. There were no significant differences between the groups in the acute phase response, as measured by circulating concentrations of C-reactive protein and zinc, but the expected effects of extradural block on circulating metabolites and white cell count were demonstrated. We conclude that IL-6 is unlikely to contribute to the initial increases in secretion of pituitary hormones found during surgery, but a later effect of the cytokine on endocrine responses cannot be excluded.

Acute-Phase Proteins↗
PubMed1994

Growth hormone suppression and glutamine flux associated with cardiac surgery.

Pharmacological doses of growth hormone (GH) in humans and rats increase plasma and muscle glutamine values. As major surgery results in a physiological rise in serum GH concentration, we investigated whether this physiological increase in GH altered glutamine metabolism. Eighteen patients undergoing coronary artery bypass graft (CABG) surgery were randomly assigned to receive somatostatin, 100 micrograms subcutaneously at induction of anaesthesia and 8 hourly for 48 h, or placebo. Somatostatin effectively blocked the physiological surge of GH following injury but did not affect plasma or muscle glutamine concentrations, which fell significantly in both groups. Plasma glutamine decreased by 31% (P < 0.01) and 28% (P < 0.01) in the control and somatostatin groups respectively. Muscle glutamine was reduced 45% (P < 0.001) in the control group and 50% (P < 0.001) in the somatostatin group. There was no difference in muscle or circulating glutamate, alanine or branched chain amino acid concentrations or in metabolite values between the somatostatin-treated patients and the control group. There was no relationship between the GH response to surgery and glutamine metabolism following major surgery.

Blood Glucose↗
PubMed1993

Eltanolone for induction of anaesthesia and to supplement nitrous oxide for minor gynaecological surgery.

We have used eltanolone to induce anaesthesia and by intermittent injection to supplement nitrous oxide during maintenance in 50 patients undergoing minor gynaecological surgery; opioids were not used. Induction of anaesthesia was remarkably trouble free and achieved with a single dose of 0.5 mg.kg-1 in 90% of patients. Pain on injection was not a feature. Satisfactory anaesthesia was achieved in 84% of patients; eight required addition of isoflurane. There were minimal cardiovascular changes and apnoea on induction occurred in only one patient. Recovery times were acceptable.

Abortion, Therapeutic↗
PubMed1992

Midazolam sedation reversed with flumazenil for cardioversion.

Midazolam was used for anaesthesia in 20 patients undergoing cardioversion; 10 received flumazenil, which caused immediate rapid reversal of anaesthesia, and these patients maintained SpO2 greater than 95%, breathing air, within 5-10 min. In contrast, patients in the placebo group were still partially sedated and required oxygen therapy for up to 2 h to maintain a normal SpO2. Arterial pressure, but not heart rate, also was greater in the flumazenil group in the recovery period.

Adult↗
PubMed1992

Ketorolac for postoperative analgesia in elderly patients.

Ketorolac was compared with papaveretum followed by paracetamol plus dextropropoxyphene orally, for postoperative pain relief in elderly orthopaedic patients. Seventy-two patients over the age of 65 years were entered into a double-blind, randomised trial. Pain and pain relief were recorded during an intramuscular and an oral phase, lasting up to 8 days, and a global assessment was made at the end of the study. No difference was demonstrated between the two treatment groups. The incidence of side effects was similar in both groups. It was concluded that ketorolac could provide pain relief equivalent to papaveretum for many patients.

Aged↗
PubMed1992

Pregnanolone: a new steroid intravenous anaesthetic. Dose-finding study.

The intravenous steroid anaesthetic pregnanolone has been investigated as an induction agent in 60 fit adults premedicated with morphine and atropine. The drug was given in a stepwise fashion starting with 0.5 mg.kg-1; following a successful induction, the next patient received 15% less, while the subsequent patient received 15% more if anaesthesia was not achieved. Taking loss of eyelash reflex as the end point, 31 patients were satisfactorily induced; the AD50 in these patients was 0.44 mg.kg-1 (95% CI 0.41-0.47). A further 23 patients were induced satisfactorily as assessed by cessation of counting. Induction was trouble free with minimal changes in heart rate and arterial blood pressure, a low incidence of apnoea and few involuntary movements; pain on injection was not a feature. Loss of eyelash reflex is not a good end point for assessment of loss of consciousness following pregnanolone.

Adult↗
PubMed1991

Gas gangrene.

Explore the source record for details and available documents.

Adult↗
PubMed1991

The stability of carboplatin, diamorphine, 5-fluorouracil and mitozantrone infusions in an ambulatory pump under storage and prolonged 'in-use' conditions.

Drug infusions can be exposed for prolonged periods to 'in-use' conditions where the temperature of an infusion in a holster-worn infusion pump may reach 37 degrees C. In this study, the stability of three cytotoxic drug infusions (carboplatin, 5-fluorouracil and mitozantrone) and one analgesic infusion (diamorphine HCl) was determined in Parker Micropump medication reservoirs under refrigerated storage and prolonged in-use conditions. The stability of the three cytotoxic drug infusions was unaffected by 14 days storage at either 4 or 37 degrees C. The diamorphine HCl infusion was stable over 14 days storage at 4 degrees C but under in-use conditions at 37 degrees C, drug degradation became significant (greater than 5%) if storage exceeded 7 days.

Carboplatin↗
PubMed1990

Internal jugular catheterisation. Case report of a potentially fatal hazard.

A case is presented of acute life-threatening haemorrhage caused by laceration of the subclavian artery as a result of attempted cannulation of the internal jugular vein. This sequence of events has not been reported previously, and probably resulted from use of a cannula-over-needle system.

Catheterization, Central Venous↗
PubMed1990

Comparison of intramuscular ketorolac and morphine in pain control after laparotomy.

Ketorolac, a prostaglandin synthetase-inhibiting analgesic, was compared with morphine for relief of pain after laparotomy for gynaecological surgery. Eighty patients were studied; they were given either ketorolac 30 mg intramuscularly followed by 10 mg 4-hourly as required, or morphine 10 mg intramuscularly 4-hourly as required, administered in a double-blind, randomised fashion. Pain scores (verbal and visual analogue) were recorded at baseline and assessed at 30 and 60 minutes and then hourly for 6 hours. Pain relief was measured at the same times. Pain and pain-relief scores were further assessed on the evening of day 1 and at 24 hours. Pain scores were similar in the two groups but pain-relief scores were better in the morphine group. A considerable number of patients suffered postoperative nausea and vomiting but there was no difference between the groups. One patient in the ketorolac group had unexplained hypotension. It is concluded that ketorolac can provide effective postoperative analgesia.

Adult↗
PubMed1988

Quantitation of human serum polymeric IgA, IgA1 and IgA2 immunoglobulin by enzyme immunoassay.

This report concerns the relative quantitation of serum polymeric IgA and polymeric IgA subclass concentrations by enzyme immunoassay (EIA). The assay relies on the specific binding of polymeric IgA to secretory component. Competition between pentameric IgM and polymeric IgA for binding to secretory component was observed. Thus, samples were adsorbed for IgM by affinity chromatography before the EIA was performed. The assay was used to determine an age-related range of serum polymeric IgA concentrations and to compare the polymeric IgA concentrations in patients with IgA nephropathy (n = 50) to those of controls (n = 50). The serum concentrations of both polymeric IgA and polymeric IgA1 increased with age reaching adult values of around 12 years of age. Polymeric IgA2 concentrations did not reach adult levels until 18 years of age. The ratio of the polymeric IgA concentration to the total serum IgA concentration was found to be significantly increased in children under 2 years of age compared with those over 4 years of age (Mann-Whitney U-test, P less than 0.01). Patients with IgA nephropathy had significantly increased concentrations of polymeric IgA (P = 0.001) and polymeric IgA1 (P = 0.001) but similar polymeric IgA2 concentrations to controls.

Adolescent↗
PubMed1986

Leigh's disease.

Explore the source record for details and available documents.

Brain Diseases, Metabolic↗
PubMed1985

Suppression of secondary hyperparathyroidism in children with chronic renal failure by high dose phosphate binders: calcium carbonate versus aluminium hydroxide.

Secondary hyperparathyroidism was suppressed over a period of one year in 12 children with chronic renal failure by using a regimen of mild dietary phosphate restriction and high dose phosphate binders. The patients were randomised to receive either aluminium hydroxide or calcium carbonate by mouth for six months and then crossed over to the other medication. Vitamin D (dihydrotachysterol) dosage was unchanged. Serum parathyroid hormone concentrations were reduced to within the normal range, urinary cyclic adenosine monophosphate values fell, plasma phosphate concentrations decreased, and the theoretical renal phosphate threshold increased significantly. Transiliac bone biopsy findings improved in four patients with adequate suppression of parathyroid hormone concentrations, deteriorated in two patients who were not compliant, and did not change in five patients in whom initial bone disease was mild. Growth velocity improved significantly. There was no difference in the clinical response, biochemical changes, or incidence of complications during treatment with the two agents. In view of the risk of aluminium toxicity the use of high dose calcium carbonate with dietary phosphate restriction and vitamin D supplementation is recommended in the control of secondary hyperparathyroidism in children with chronic renal failure.

Adolescent↗