Search PubMed⌕ Search

Biomedical subjects

A Duncan

Publications and source records attributed to A Duncan.

At least 145 records · Page 8Linked to original sources
PubMed1988

Effect of intragastric pH on mucosal protective action of sucralfate.

Acid intragastric pH is believed to be mandatory for mucosal protective action of sucralfate, but evidence for its efficacy at neutral pH is lacking. The effect of sucralfate on gastric mucosal erosions induced by oral administration of aspirin and bile acids at acidic pH of 1.5 and 3.9, and near neutral pH of 6.5 was investigated in 320 rats. The effect of sucralfate on the intragastric pH four hours after the ingestion of test solutions was also examined. The incidence and severity of mucosal erosions induced by aspirin and bile acids were lower in animals treated with sucralfate at acidic (p less than 0.001) and near neutral (p less than 0.01) intragastric pH. Mucosal protection was greater with ingestion of sucralfate 300 mg/kg and 200 mg/kg, than with 100 mg/kg. The intragastric pH was higher (p less than 0.001) in sucralfate treated groups at pH 3.9 and 6.5. This study provides evidence that sucralfate protects against mucosal injury at near neutral, as well as at acidic pH.

Animals↗
PubMed1988

Can 111indium autologous mixed leucocyte scanning accurately assess disease extent and activity in Crohn's disease?

111Indium autologous mixed leucocyte scanning has recently been used for the investigation of Crohn's disease. Nineteen patients had indium scans to assess disease extent and activity. The scans were compared with conventional imaging techniques and indices of disease activity including clinical scores, ESR, CRP, and GI protein loss. In five patients with active disease the scans were negative and overall there was poor correlation between the scan scores and the other indices of disease activity. Indium scanning correctly located extent of disease in only 58% of patients. 111Indium mixed leucocyte scanning may be more suited for the assessment of disease extent and activity in severely ill patients with Crohn's disease.

Adolescent↗
PubMed1988

Acute epiglottitis: a different approach to management.

Between January 1979 and October 1986, 349 patients with epiglottitis were admitted to the Royal Children's Hospital, Melbourne, Australia. Forty-five (13%) patients were not intubated, 291 (83%) were managed by nasotracheal intubation and spontaneous respiration without sedation, three (1%) received continuous positive airway pressure, and ten (3%) were ventilated. The 294 patients who were not ventilated were intubated for a mean of 18 +/- 9.5 (SD) h; 90% were extubated within 24 h. Criteria for extubation included resolution of fever (less than 37.5 degrees C), passage of time (12 to 16 h), and improvement in the general appearance of the child. Laryngoscopy was not performed before extubation. Providing there is always a doctor present who can reintubate if accidental extubation occurs, routine use of sedation, paralysis and mechanical ventilation, and pre-extubation laryngoscopy are not required for the management of children with uncomplicated epiglottitis, and their use may prolong the period of intubation.

Acute Disease↗
PubMed1987

Is an acid pH medium required for the protective effect of sucralfate against mucosal injury?

It has been suggested that an acidic medium is required for the action of sucralfate in providing mucosal protection. We have examined the effect of sucralfate (300 mg/kg) at an acidic pH of 1.5 and a near-neutral pH of 6.5 on the occurrence of mucosal damage induced in rats by aspirin alone and aspirin combined with bile acids. Fasting Sprague-Dawley rats received test solutions by oral intubation, and their stomachs were examined four hours later for the presence of hemorrhagic erosions. Sucralfate significantly reduced mucosal erosions induced by aspirin alone and aspirin combined with bile acids at pHs of both 1.5 and 6.5. These results indicate that the protective effect of sucralfate against mucosal injury induced by aspirin and bile acids is not dependent on an acidic medium.

Animals↗
PubMed1987

Pyridinium crosslinks of bone collagen and their location in peptides isolated from rat femur.

The relative proportions of pyridinoline and deoxypyridinoline in bone showed large species variations, although the total number of pyridinium crosslinks in rat, rabbit and bovine bone collagen was only 25-30% of that found in articular cartilage. Three pyridinium-containing peptides were isolated from cyanogen bromide digests of rat femoral bone and were characterized by their Mr values and amino-acid compositions. The results showed that pyridinoline and its deoxy analogue were equally distributed at two locations stabilizing the 4D stagger through interactions involving both the N- and C-terminal telopeptide regions. Less than stoichiometric amounts of pyridinium crosslinks were present in the peptides, suggesting that the isolated peptides contained additional (unidentified) maturation products of the bifunctional, reducible crosslinks.

Animals↗
PubMed1987

Dual-photon bone densitometry in normal Australian women: a cross-sectional study.

Osteoporosis is a major health problem in Australia, as it is in most Western societies. Bone mineral density in the spine and femoral neck are accurate indicators of osteopenia and thus useful indicators of the risk of a fracture. Dual-photon absorptiometry is a non-invasive technique that allows the accurate quantitation of bone mineral density in the lumbar vertebrae and proximal femur with a low radiation exposure. The increasing availability of this technique dictates the requirement for "normal" ranges and quality control. We report here lumbar vertebral and proximal femur bone mineral density as measured by dual-photon absorptiometry in 179 normal Australian women. Forearm bone mineral content in these subjects, as measured by single-photon absorptiometry, is also presented. There was a relative stability of lumbar bone mineral density and forearm bone mineral content before the menopause, after which there was an age-related decline. On the other hand, bone mineral density at all three sites in the proximal femur showed an age-related decline throughout adult life. Intraoperator variability in calculated bone mineral density did not exceed 2.3%. The requirement for correct positioning of the patient is illustrated. The data allow statistical analysis and the development of normal ranges. They provide an Australian base against which individual patient values can now be compared.

Adult↗
PubMed1987

A novel whole blood capillary technic for measuring the prothrombin time.

The prothrombin time (PT) is frequently performed to monitor anticoagulant therapy. Although relatively simple to perform, it requires venipuncture and laboratory resources for sample handling and analysis. A recently developed capillary whole blood device that uses fingerstick samples was evaluated. Paired capillary whole blood and reference plasma PTs were performed in 858 samples from 732 subjects. The PT for normal volunteers (n = 193) was 11.8 +/- 0.9 seconds with the use of the new instrument and 12.1 +/- 0.5 seconds with the use of the reference method. In samples from 539 patients receiving anticoagulants, the correlation coefficient between the two methods was 0.96. Venous whole blood without anticoagulant and capillary whole blood gave equivalent results, which suggests that the fingersticks do not effect the quality of the specimen. Variation in hematocrit between 23.4% (0.34) and 53.8% (0.538) did not alter the performance of the instrument. The new instrument is easy to use and may allow testing by nonlaboratory personnel and patients. It obviates the need for venipuncture, provides immediate results, and appears to be comparable in accuracy to current reference methods.

Anticoagulants↗
PubMed1987

Intussusception following abdominal trauma.

We reviewed the charts of 21 patients on the Trauma Service who were operated on for intestinal obstruction for the years 1983 through 1985. Six (28.6%) of the 21 patients had intussusception as the cause of their obstruction post-laparotomy for trauma. All were males ages 17 to 25 years. The mechanisms of injury were gunshot wounds in three, stab wounds in two, and blunt trauma in one. Five patients were hypotensive on admission with systolic BP less than 70, and two patients received uncrossmatched blood preoperatively. Injuries at exploration included liver laceration (six patients), gastric perforation (two patients), and diaphragmatic lacerations, splenic laceration, renal injury, and ventricular injury, one each. No patient suffered small intestinal injuries and we cannot explain the occurrence of intussusception. Intussusception occurred in the first 8 postoperative days in four patients and at 21 days, and 10 months, in the remaining two. The diagnosis was made twice by CT scan preoperatively. Jejunojejunal intussusception was common (five patients), jejunoileal in one and ileocolic in one (who also had a jejunojejunal intussusception). All patients were treated with manual reduction alone and none recurred. There were no postoperative complications and all patients were discharged by the eighth postoperative day. Our study suggests that early postoperative obstruction is caused by intussusception with unexpected frequency in trauma patients, and can be diagnosed by CT scan in some cases. Treatment with operative reduction has an excellent prognosis.

Abdominal Injuries↗
PubMed1987

The dangers of premature extubation after severe birth asphyxia.

The records of all 91 neonates with asphyxia who were referred to the Royal Children's Hospital in 1982 and 1983 were reviewed and information was obtained on their subsequent neurological outcome. Thirty children had been extubated after their initial resuscitation, before transfer to the Royal Children's Hospital; 21 of these children had been extubated despite the fact that they had taken more than 5 min to take their first breath, and 11 (52%) of them died (while none of the nine infants who breathed within 5 min died). A paediatrician was involved with two-thirds of the 21 children who were extubated despite having more than 5 min to breathe. Twelve children required cardiac massage; seven of them were extubated and then reintubated before transfer, and six of the seven infants died. These findings suggest that many paediatricians are not aware of the importance of continuing ventilatory support in neonates who have suffered a severe asphyxial insult. Asphyxiated babies who require cardiac massage, and babies who do not start breathing within 5 min of birth, should not be extubated as soon as they have established regular respiration; they should remain intubated and be transferred to an intensive care unit.

Asphyxia Neonatorum↗
PubMed1987

Vertebral artery injury--diagnosis and management.

The literature on vascular trauma contains little information on the management of vertebral artery injuries. We have reviewed our experience consisting of 23 patients with vertebral artery injuries caused by 19 gunshot wounds, two stab wounds, one shotgun wound, and one blunt injury. Twelve patients sustained unilateral vertebral artery thrombosis, seven patients had vertebral AV fistulae (three jugular vein, four vertebral vein) and four patients sustained mural injury without thrombosis. Six patients (26.1%) developed major neurologic deficits of which five could be directly attributed to CNS missile injury. One patient had transient vertebrobasilar ischemia on the basis of a vertebral AV fistula. Four of the seven vertebral AV fistulae were managed solely by therapeutic embolization and two patients early in the series underwent surgical management alone. One patient had therapeutic embolization of the proximal vertebral artery and operative distal vertebral artery ligation for an AV fistula. The four patients who died (17.4%) did so as a direct result of their CNS missile injury. We conclude that: 1) unilateral vertebral artery occlusion seldom results in a neurologic deficit if there is a normal contralateral vertebral artery and PICA (posterior inferior cerebellar artery) blood supply is preserved; 2) accurate assessment of a vertebral artery injury requires contralateral vertebral arteriogram; 3) management of vertebral artery injury is simplified by proximal, and if possible distal, therapeutic embolization; 4) an anterior approach to the C1-2 vertebral artery is a satisfactory method of obtaining distal surgical control, obviating the need to unroof the bony canal of the vertebral artery; 5) angiography is necessary in penetrating neck trauma to identify occult vascular injuries.

Adolescent↗
PubMed1986

Early open reduction and internal fixation of the disrupted pelvic ring.

Early open reduction and internal fixation (ORIF) of extremity fractures in patients with multiple injuries has been demonstrated to be safe, improve survival, and decrease the incidence of respiratory failure. Complications leading to abandonment of planned operative fixation and death in several patients with pelvic fractures led us to initiate a policy of early ORIF of the disrupted pelvic ring. Early ORIF of the pelvis was performed in 15 multiply injured patients between May 1984 and August 1985. Patients ranged in age from 13 to 79 years, their Hospital Trauma Index-ISS scores ranged from 14 to 68, and number of preoperative transfusions ranged from 0 to 42. Types of fractures were A-P compression, two, lateral compression, one, vertical shear, seven, complex, two, and acetabulum with ring disruption, three. All patients were resuscitated, transported in pneumatic antishock garments, and evaluated by abdominal and pelvic CT scan (in two patients following celiotomy). Preoperative angiograms to assess retroperitoneal hemorrhage in eight patients resulted in identification and control of significant bleeding in five. The mean time from injury to pelvic stabilization was 38 hours. Seven patients underwent ORIF within the first 24 hours. In most cases simultaneous anterior and posterior internal fixation was performed with the patient in the lateral decubitus position. Excluding associated procedures, operative time averaged 5.1 hours. Intra-operative transfusions averaged 4 units (range, 0-11). Rigid fixation was achieved in all patients. Most patients were out of bed by the third postoperative day. No patient developed respiratory failure. Two patients developed wound infections. Modification of our technique has avoided this complication in the latter part of this series.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗