Showing papers by "Royal Adelaide Hospital published in 1991"

Relationships between oesophageal transit and solid and liquid gastric emptying in diabetes mellitus.

Abstract: In 87 randomly selected diabetic patients (67 type 1, 20 type 2) and 25 control subjects, gastric emptying of digestible solid and liquid meals and oesophageal transit of a solid bolus were measured with scintigraphic techniques. Gastrointestinal symptoms, autonomic nerve function and glycaemic control were evaluated in the diabetic patients. Gastric emptying and oesophageal transit were slower (P less than 0.001) in the diabetic patients compared with the control subjects, and each was delayed in about 40% of them. There was a relatively weak (r = 0.32; P less than 0.01) relationship between solid and liquid gastric emptying, and no significant correlation (r = 0.11, NS) between oesophageal transit and gastric emptying of the solid meal. Scores for upper gastrointestinal symptoms and autonomic nerve function correlated weakly (r = 0.21; P less than 0.05) with both oesophageal transit and gastric emptying. Gastric emptying of the liquid meal was slower (P less than 0.05) in patients with blood glucose concentrations greater than 15 mmol/l. These results indicate that gastric emptying in patients with diabetes mellitus should be assessed by liquid as well as by solid test meals and that oesophageal transit should not be used as a predictor of generalised diabetic gastroenteropathy.

Provocation of transient lower esophageal sphincter relaxations by meals in patients with symptomatic gastroesophageal reflux

Abstract: The effect of a meal on the rate of transient lower esophageal sphincter (LES) relaxations and patterns of gastroesophageal reflux was investigated in 49 patients referred for evaluation of gastroesophageal reflux. Esophageal motility and pH were recorded concurrently before and after a standard meal. In the patients with symptomatic reflux, the meal induced a four- to sevenfold increase in the gastroesophageal reflux through two mechanisms: a four- to fivefold increase in the rate of transient LES relaxations and an increase in the proportion of transient LES relaxations accompanied by reflux from 47% to 68%. Overall the rate of reflux episodes that occurred by mechanisms other than transient LES relaxation did not increase significantly. An exception to these findings were those in six patients with chronically absent basal LES pressure in whom transient LES relaxations could not be scored. In these patients, reflux increased postprandially through mechanisms other than transient LES relaxation. These findings confirm the pivotal importance of transient LES relaxations in the pathogenesis of gastroesophageal reflux.

Potential errors in pulse oximetry. II. Effects of changes in saturation and signal quality.

Abstract: The published studies of pulse oximeter performance under conditions of normal, high and low saturation, exercise, poor signal quality and cardiac arrhythmia are reviewed. Most pulse oximeters have an absolute mean error of less than 2% at normal saturation and perfusion; two-thirds have a standard deviation (SD) of less than 2%, and the remainder an SD of less than 3%. Some pulse oximeters tend to read 100% with fractional saturations of 97-98%. Pulse oximeters may be suitable hyperoxic alarms for neonates if the alarm limit chosen is directly validated for each device. Pulse oximeters are poorly calibrated at low saturations and are generally less accurate and less precise than at normal saturations; nearly 30% of 244 values reviewed were in error by more than 5% at saturations of less than 80%. Ear, nose and forehead probes respond more rapidly to rapid desaturation than finger probes, but are generally less accurate and less precise. Ear oximetry may be inaccurate during exercise. Low signal quality can result in failure to present a saturation reading, but data given with low signal quality warning messages are generally no less accurate than those without. Cardiac arrhythmias do not decrease accuracy of pulse oximeters so long as saturation readings are steady.

Role of the proximal and distal stomach in mixed solid and liquid meal emptying.

Abstract: The role of the proximal and distal stomach in the emptying of solids and liquids from the stomach remains unclear. We have used a dual isotope technique to quantify proximal and distal stomach emptying of a solid (100 g of 99mTc labelled liver/ground beef) liquid (either 200 ml of normal saline (eight subjects) or 25% dextrose (seven subjects) labelled with 113mIn-diethylenetriaminepenta-acetic acid) mixed meal. A manometric catheter simultaneously measured antral, pyloric, and duodenal motor activity. The liquid component dispersed rapidly throughout the stomach and emptied after a minimal lag period. The emptying of the 25% dextrose was delayed compared with the saline. This delay was associated with increased retention of the liquid in the distal stomach, a significant increase in localised phasic pyloric contractions, and a suppression of antral contractions. The solid component initially resided wholly within a proximal stomach reservoir area. Solids then redistributed from proximal to distal stomach during the emptying of liquid from the stomach. Dextrose delayed gastric emptying of solids compared with saline by increasing the solid lag period and retention in the proximal stomach. There was no significant difference between saline and dextrose meals in the distal stomach retention of solid or in the linear rate of emptying after the lag period. We conclude that, contrary to general opinion, the proximal stomach plays an important role in the control of gastric emptying of solids while the distal stomach is important in the emptying of nutrient liquids.

A prospective comparison of a percutaneous tracheostomy technique with standard surgical tracheostomy

Abstract: A prospective non-randomized study was undertaken to compare, in intensive care patients, the safety and utility of a percutaneous tracheostomy technique performed at the bedside with a surgical tracheostomy technique performed in the operating room. During a 21 month period, 153 percutaneous tracheostomies were performed. Complications occurred in 6 patients (3.9%). Secondary wound haemorrhage occurred in 4 patients and primary wound haemorrhage occurred in 2 patients. During the same period, 74 surgical tracheostomies were performed. Complications occurred in 14 patients (18.9%) which included tracheal obstruction, haemorrhage, pneumothorax, wound infection, wound breakdown and one death. In comparison to surgical tracheostomies, percutaneous tracheostomies were rapidly and easily performed at the bedside and were associated with significantly fewer complications.

Hyperglycaemia stimulates pyloric motility in normal subjects.

Abstract: The motor correlates of the delay in gastric emptying produced by hyperglycaemia were investigated in 11 healthy volunteers. Fasting gastroduodenal motility was measured during euglycaemia (blood glucose concentration 3-5 mmol/l) and during hyperglycaemia induced by intravenous dextrose (blood glucose concentration 12-16 mmol/l). Antral, pyloric, and proximal duodenal pressures were recorded by a sleeve/sidehole manometric assembly positioned across the pylorus, with the aid of measurements of transmucosal potential difference. During hyperglycaemia there was stimulation of isolated pyloric pressure waves when compared with the euglycaemia period (p less than 0.05). This was associated with inhibition of antral pressure waves (p less than 0.05). In nine of the 11 subjects an episode of duodenal 'phase III like' activity occurred within 15 minutes of the onset of hyperglycaemia. It is proposed that the stimulation of localised pyloric contractions and inhibition of antral contractions contribute to the delayed gastric emptying induced by hyperglycaemia. Abnormal gastric motility in patients with diabetes mellitus may be the result of hyperglycaemia itself, rather than irreversible autonomic neuropathy.

Potential errors in pulse oximetry III: Effects of interference, dyes, dyshaemoglobins and other pigments*

Abstract: Electrosurgery, patient motion and some types of lighting can cause errors in saturation readout; it is recommended that probes should be shielded from ambient lighting. Intravenous dyes can introduce gross but transient errors, which may also be present in in vitro measurements. Carboxyhaemoglobin causes overestimation of fractional saturation by an amount less than, but possibly close to, the percent of carboxyhaemoglobin present. Methaemoglobin causes the pulse oximeter readout to tend towards 85%. Fetal haemoglobin and bilirubin introduce no significant error, although they may interfere with in vitro measurements. Skin pigmentation can result in a slight decrease in accuracy. Nail polish may cause up to 6% underestimation of saturation; it is recommended that probes should be mounted sideways on fingers with nail polish or long nails. Adhesive tape or a vinyl glove across the probe has no demonstrable effect on accuracy. A blood sample should be analysed by a multiwavelength in vitro oximeter when an erroneous pulse oximeter reading is suspected, although errors may be introduced in the in vitro reading by fetal haemoglobin, bilirubin and intravenous dyes.

Clinical efficacy of oral-transdermal clonidine combinations during the perioperative period.

Abstract: In an attempt to maintain stable levels of an alpha 2-adrenergic agonist throughout the perioperative period, two different oral-transdermal clonidine dosage regimens were administered according to a randomized, double-blind, placebo-controlled study in patients undergoing abdominal surgery. We determined the clinical efficacy of a high- and a low-dose clonidine regimen on sedation, hemodynamic parameters, anesthesia, and analgesia. The low-dose clonidine group of patients (n = 14) received a 7-cm2 clonidine transdermal patch (Catapres-TTS #2), which was supplemented with oral doses of clonidine approximately 3 micrograms.kg-1 on the evening prior to surgery and on the morning of surgery. The high-dose clonidine group (n = 14) received a 10.5-cm2 clonidine transdermal patch (Catapres-TTS #3) with oral clonidine approximately 4.5 micrograms.kg-1 at bedtime and 6.0 micrograms.kg-1 on the morning of surgery. Placebo-treated (control) patients received the same occlusive patch without active ingredient and oral placebo tablets at bedtime and on the morning of surgery. Preanesthetic medication included midazolam 50 micrograms.kg-1 intramuscularly (im). Anesthesia was induced with alfentanil 30 micrograms.kg-1 intravenously (iv), thiopental 3 mg.kg-1 iv, and vecuronium 0.1 mg.kg-1 iv, and was maintained with 70% nitrous oxide in oxygen and a continuous infusion of alfentanil 0.5 microgram.kg-1.min-1. Isoflurane was added when the blood pressure exceeded 110% of the patient's prestudy value. For pain relief postoperatively, the patients received morphine, 1-2-mg iv boluses, via a patient-controlled analgesia pump. The low-dose clonidine patient group had mean plasma clonidine concentrations that varied from 1.47 ng.ml-1 (preoperative) to 1.32 ng.ml-1 (postoperative day 2).(ABSTRACT TRUNCATED AT 250 WORDS)

Intra‐operative patient‐controlled sedation

Abstract: Summary The quality of sedation and postoperative recovery have been assessed for intra-operative sedation provided by either patient-controlled sedation with propofol or a standard method using divided doses of midazolam and fentanyl, in 40 ASA 1 day surgery patients undergoing extraction of third molar teeth under local analgesia. Patient-controlled sedation with propofol produced sedation no deeper than full eyelid closure with prompt response to verbal command, but deeper levels were seen in three patients in the midazolam and fentanyl group. Patient satisfaction was higher in the patient-controlled sedation propofol group for both subjective intra-operative feelings (p < 0.01) and willingness to have the procedure again in the same manner (p < 0.05). Amnesia was more limited to intra-operative events (rather than extending into the postoperative period) in the patient-controlled sedation propofol group (p < 0.05). Drug dose was correlated with duration of procedure and surgical difficulty in the patient-controlled sedation propofol group but not in the midazolam and fentanyl group. Postoperative testing included a new computerised test, the FAST index, which indicated a dose-dependent reduction in cognitive function in the midazolam and fentanyl group, which persisted until the time of discharge. Changes in cognitive function in the patient-controlled sedation propofol group in the same postoperative interval were significantly less and not related to propofol dose.

Potential errors in pulse oximetry. I. Pulse oximeter evaluation.

Abstract: There is no absolute reference for oxygen saturation, although multiwavelength in vitro oximeters are accepted as the 'gold standard'. Regardless of whether fractional or functional saturation is used by manufacturers to calibrate their oximeters, evaluation against fractional saturation is recommended since this is the clinically relevant variable. The use of standard notation and comparisons based on bias and precision is recommended. The accuracy of pulse oximetry is intrinsically limited by the use of only two wavelengths, and is dependent on the initial calibration population. The empirical algorithms used to convert the signal to its 'readout value' and the quality control of hardware may both be important sources of variability between oximeters. Change in blood temperature may introduce errors in pulse oximeter and in vitro oximeter saturation readings, but these will be clinically insignificant. Changes in blood pH should not decrease pulse oximetry accuracy.

Calcium absorption in normal and osteoporotic postmenopausal women.

Abstract: Hourly fractional absorption of radiocalcium (alpha), serum calcitriol, and a number of other variables were measured in 152 normal and 148 osteoporotic postmenopausal women. Alpha, body weight, and serum albumin were all significantly lower in the osteoporotic than in the normal women, and plasma alkaline phosphatase, fasting urinary calcium, sodium, and hydroxyproline were all significantly higher in the osteoporotic than in the normal group. The most significant determinant of alpha in each group was the serum calcitriol concentration, but calcium absorption relative to serum calcitriol was significantly lower in the osteoporotic than in the normal women. The serum calcitriol level was slightly but not significantly lower in the osteoporotic than in the normal group and accounted for only 20% of the difference in alpha between them. The implied "resistance" to calcitriol in the osteoporotic group was significantly related to serum albumin and body weight but independent of age. Urinary hydroxyproline was an inverse function of alpha and a positive function of fasting urinary calcium in the osteoporotic group.

Disordered Gastric Motor Function in Diabetes Mellitus: Recent Insights into Prevalence, Pathophysiology, Clinical Relevance, and Treatment

Abstract: (1991). Disordered Gastric Motor Function in Diabetes Mellitus: Recent Insights into Prevalence, Pathophysiology, Clinical Relevance, and Treatment. Scandinavian Journal of Gastroenterology: Vol. 26, No. 7, pp. 673-684.

Cigarette smoking and rate of gastric emptying: effect on alcohol absorption.

Abstract: OBJECTIVE--To examine the effects of cigarette smoking on alcohol absorption and gastric emptying. DESIGN--Randomised crossover study. SETTING--Research project in departments of medicine and nuclear medicine. SUBJECTS--Eight healthy volunteers aged 19-43 who regularly smoked 20-35 cigarettes a day and drank small amounts of alcohol on social occasions. INTERVENTIONS--Subjects drank 400 ml of a radiolabelled nutrient test meal containing alcohol (0.5 g/kg), then had their rates of gastric emptying measured. Test were carried out (a) with the subjects smoking four cigarettes an hour and (b) with the subjects not smoking, having abstained for seven days or more. The order of the tests was randomised and the tests were conducted two weeks apart. MAIN OUTCOME MEASURES--Peak blood alcohol concentrations, absorption of alcohol at 30 minutes, amount of test meal emptied from the stomach at 30 minutes, and times taken for 50% of the meal to leave the proximal stomach and total stomach. RESULTS--Smoking was associated with reductions in (a) peak blood alcohol concentrations (median values in non-smoking versus smoking periods 13.5 (range 8.7-22.6) mmol/l v 11.1 (4.3-13.5) mmol/l), (b) area under the blood alcohol concentration-time curve at 30 minutes (264 x 10(3) (0-509 x 10(3)) mmol/l/min v 140 x 10(3)) (0-217 x 10(3) mmol/l/min), and (c) amount of test meal emptied from the stomach at 30 minutes (39% (5-86%) v 23% (0-35%)). In addition, smoking slowed both the 50% gastric emptying time (37 (9-83) minutes v 56 (40-280) minutes) and the intragastric distribution of the meal. There was a close correlation between the amount of test meal emptied from the stomach at 30 minutes and the area under the blood alcohol concentration-time curve at 30 minutes (r = 0.91; p less than 0.0001). CONCLUSION--Cigarette smoking slows gastric emptying and as a consequence delays alcohol absorption.

Substance P-containing neurons in the mesopontine tegmentum are severely affected in Parkinson's disease.

Abstract: Substance P immunoreactive (SP+) neurons were analysed quantitatively in serial sections of the mesopontine tegmentum in 6 patients with idiopathic Parkinson's disease and 5 age-matched normal controls. In the tegmentum of the Parkinson's disease brains many SP+ neurons contained swollen, twisted neuronal processes as well as Lewy bodies. There were significant reductions in the total number of SP+ neurons in the pedunculopontine tegmental nucleus (loss 43%), in the laterodorsal tegmental nucleus (loss 28%), in the oral pontine reticular nucleus (loss 41%) and in the median raphe nucleus (loss 76%). It was the large SP+ (greater than 20 microns) neurons that were particularly affected. In our control group we did not document a significant relationship between age at death and number of SP+ neurons in these tegmental nuclei or between age at death and number of pigmented neurons in the locus coeruleus. In contrast, in patients with Parkinson's disease, there was a strong inverse relationship between age at death and numbers of SP+ and pigmented neurons. Our findings suggest an interaction between the pathophysiological mechanisms initiated by Parkinson's disease and other processes related to ageing. Since tegmental SP+ neurons are affected by the primary pathological processes underlying Parkinson's disease as severely as catecholamine-synthesizing neurons are affected, theories of pathogenesis and therapeutic strategies in Parkinson's disease will need to take into account the involvement of these SP+ neurons.

Air embolism of the brain in rabbits pretreated with mechlorethamine.

Abstract: Infusion of 400 microliters air into the left internal carotid artery of five anesthetized rabbits caused transient pial arteriole air embolism, an immediate 41.9 +/- 0.8% dilatation of the embolized vessels, suppression of the cortical somatosensory evoked response to 29.4 +/- 2.7% of baseline, and a progressive decline in ipsilateral cerebral blood flow (measured by hydrogen clearance) to 46 +/- 4.1% of baseline after 2 hours. These values were significantly different from those at baseline and from the responses of 10 control rabbits given equivalent intracarotid saline infusions. Twelve other rabbits were made leukopenic by treatment with 1.5 mg/kg i.v. mechlorethamine 72 hours prior to study. Mean +/- SEM leukocyte count decreased from 6,320 +/- 73/mm3 to 1,890 +/- 66/mm3 without any change in the leukocyte differential or erythrocyte and platelet counts. Intracarotid infusion of saline into seven of the leukopenic rabbits caused no changes. In the other five leukopenic rabbits, infusion of 400 microliters air caused air embolism but did not produce the anticipated declines in cerebral blood flow or the cortical somatosensory evoked response, both of which remained indistinguishable from baseline values and responses in the seven saline-treated leukopenic controls. Similarly, air-embolized arterioles showed nonsignificant dilatation in leukopenic rabbits. Our data suggest that the decreases in both cerebral blood flow and brain function seen after air embolism require the presence of leukocytes.

Pulse oximeter probes A comparison between finger, nose, ear and forehead probes under conditions of poor perfusion*

Abstract: The performances of 10 pulse oximeters using finger probes were compared with the same pulse oximeters using alternative probes (eight finger probes, two nose probes and a forehead probe) in poorly perfused patients. All readings were then compared with directly measured arterial blood oxygen saturations. The mean difference (bias, 'accuracy'), standard deviation (precision) and 'drop out' rate for each pulse oximeter combination was determined. An overall ranking of performance of each pulse oximeter was calculated using five criteria (accuracy, precision, number of readings within 3% of standard, percentage of readings given within 3% of standard, expected overread limit in 95% of cases). Nose and forehead probes performed poorly. Some ear probes performed well compared to some finger probes, but the overall performance of probes in other sites compared to finger probes was worse, (p = 0.05). Two of eight ear probes and no nose or forehead probes would be expected to be within 4% of the reference value in 95% of readings. The use of finger probes rather than probes in other sites is recommended in the patient with poor peripheral perfusion.

Further experience with the lateral arm free flap.

Abstract: Our experience with the lateral arm free flap over the last 7 years was reviewed in detail, placing emphasis on the clinical aspects and modifications of the flap. A total of 150 patients have undergone reconstructive procedures with the flap for small to medium-sized defects. This included 18 split flaps, 11 osteocutaneous flaps, 6 with vascularized triceps tendon, 5 neurosensory flaps, and 5 fascia-fat flaps. The donor-site scar was generally acceptable; only 3 patients required scar revision and 15 patients required debulking of the flaps. With use of the split flap for wide defects, tension-free primary closure of the donor site can be achieved. In most cases, a two-team approach may be adopted, thereby increasing the efficiency of this microvascular transfer.

Head injuries in infants and young children: the value of the Paediatric Coma Scale. Review of literature and report on a study.

Abstract: The normal verbal and motor responses embodied in the standard Glasgow Coma Scale (GCS) are not achievable during the first few years of life The recent literature contains numerous reports of attempts to devise scales of responses quantitating the conscious level in infants and young children, both for research purposes and as clinical guides; some of these scales incorporate items, eg brainstem reflexes, that are not included in the GCS We have reported on a simple paediatric version of the GCS, which uses the standard scale with minor modifications in the verbal component, and sets realistic age-related normal responses This has been tested prospectively in a series of 60 head-injured infants and children (age range 0-72 months) Of 6 cases recorded as comatose 6 h after injury, 4 have confirmed or suspected residual disabilities Of 35 cases considered to be fully conscious at 6 h, 31 have made good recoveries and only 1 has suspected residual disabilities The study suggests that the scale accords with the realities of neurological immaturity, and confirms that it can be used in routine paediatric practice For comparative therapeutic trials, the conscious level in infants has limited value as an index of brain injury, and should be complemented by other indices, such as brainstem reflexes

Intra-operative patient-controlled sedation. Comparison of patient-controlled propofol with anaesthetist-administered midazolam and fentanyl.

Abstract: The quality of sedation and postoperative recovery have been assessed for intra-operative sedation provided by either patient-controlled sedation with propofol or a standard method using divided doses of midazolam and fentanyl, in 40 ASA 1 day surgery patients undergoing extraction of third molar teeth under local analgesia. Patient-controlled sedation with propofol produced sedation no deeper than full eyelid closure with prompt response to verbal command, but deeper levels were seen in three patients in the midazolam and fentanyl group. Patient satisfaction was higher in the patient-controlled sedation propofol group for both subjective intra-operative feelings (p less than 0.01) and willingness to have the procedure again in the same manner (p less than 0.05). Amnesia was more limited to intra-operative events (rather than extending into the postoperative period) in the patient-controlled sedation propofol group (p less than 0.05). Drug dose was correlated with duration of procedure and surgical difficulty in the patient-controlled sedation propofol group but not in the midazolam and fentanyl group. Postoperative testing included a new computerised test, the FAST index, which indicated a dose-dependent reduction in cognitive function in the midazolam and fentanyl group, which persisted until the time of discharge. Changes in cognitive function in the patient-controlled sedation propofol group in the same postoperative interval were significantly less and not related to propofol dose.

Heparin and heparan sulphate are inhibitors of human leucocyte elastase.

Abstract: 1. Heparin and heparan sulphate strongly inhibited human leucocyte elastase activity in an automated assay using the soluble substrate, n-succinyl-(l-alanine)3-p-nitroanilide (50% inhibition of 250 μl of 10 μg of human leucocyte elastase/ml was obtained with 80 μl of 2.8 μg of heparin/ml and 8 μg of heparan sulphate/ml). Less significant inhibition at the same concentrations was seen with the other glycosaminoglycans tested: hyaluronic acid and chondroitin sulphates A–C. 2. Heparin and heparan sulphate also strongly inhibited human leucocyte elastase activity towards insoluble human lung elastin, as determined by an e.l.i.s.a. for soluble elastin-derived peptides released by elastolytic activity on the elastin. This inhibition was shown not to be due to a direct interference of the glycosaminoglycans in the e.l.i.s.a. nor to the inhibition causing a change in the size of the elastin-derived peptides. However, unlike the chromogenic assay with n-succinyl-(l-alanine)3-p-nitroanilide as substrate, where heparin was the more effective inhibitor, in this assay system heparan sulphate was the more effective inhibitor (50% inhibition of 100 μl of 50 ng of human leucocyte elastase/ml was obtained with 100 μl of 4.5 μg of heparin/ml and 0.8 μg of heparan sulphate/ml). These results suggest that heparin and heparan sulphate, as components of cellular and basement membranes, are likely to have a role in protecting structural proteins, such as elastin, from the proteolytic activity of human leucocyte elastase. 3. The degree of inhibition by heparin was independent of pH within the range of pH studied (pH 6–9) and was almost immediate in the automated chromogenic assay system where a 10 s preincubation step was used. The inhibitory effect of heparin could be prevented by the addition of protamine sulphate or by the removal of heparin by an ion-exchange resin. 4. Low Mr preparations of heparin were also found to inhibit human leucocyte elastase, although preparations with Mr of 2000 or less did not inhibit the enzyme to the same extent as commercial preparations. 5. Heparin at the same concentrations did not inhibit other leucocyte enzymes, such as cathepsin G and myeloperoxidase, nor the pancreatic enzymes, pancreatic elastase, trypsin and chymotrypsin.

The effect of short-term dietary supplementation with glucose on gastric emptying in humans.

Abstract: In order to test whether gastric motility can adapt to changes in nutrient load, gastric emptying of hyperosmotic glucose and protein drinks was measured by applied potential tomography in two groups of ten volunteers following dietary supplementation with 400 g glucose/d for 3 d. The half emptying time for the glucose test meal was significantly faster after the standard diet had been supplemented with glucose compared with the standard diet alone (median and range, 20.7 (4.6-36.8) v. 29.1 (19.8-38.4) min; P less than 0.05), while the emptying of the protein drink (Oxo; Brooke Bond Ltd) was unchanged (median and range, 18.0 (12.5-23.6) v. 16.1 (9.6-22.7) min). These results suggest that rapid and specific adaptation of the small intestinal regulatory mechanisms for gastric emptying of nutrient solutions can occur in response to increases in dietary load. This adaptation may be explained by desensitization of nutrient receptors or by a reduction in the area of receptor field exposed to nutrients caused by increased absorption of glucose in the upper small intestine.

Stress fracture of the lumbar pedicle. Case reports of "pediculolysis" and review of the literature.

Abstract: Cases of lumbar pedicle stress fractures are described and the term "pediculolysis" introduced. The condition may be bilateral or, more commonly, may occur in association with contralateral spondylolysis. A method of direct repair with pedicle screw fixation is described.

The human humoral immune response to Salmonella typhi Ty21a.

Abstract: The short-term kinetics and the effects of different dose regimens and formulations on the humoral immune response induced in human subjects by the live attenuated typhoid vaccine Salmonella typhi Ty21a were examined. Antibody responses in jejunal fluid and serum and by specific antibody production in vitro by peripheral blood lymphocytes to S. typhi lipopolysaccharide were determined. A short vaccination schedule of three doses of 10(11) live organisms over 5 days induced significantly greater intestinal IgA antityphoid antibody responses than did two comparable doses 21 days apart. The humoral immune response was dose dependent with 10(10) and 10(11) live organisms stimulating greater intestinal immune responses than did 10(11) killed organisms. No responses were evident with either 10(9) viable organisms or with an enteric-coated preparation. In the continued development and assessment of oral typhoid vaccines, the effects of different doses and formulations and the timing of sampling on the humoral immune response should be considered.

Attempted suicide in Adelaide and Perth: changing rates for males and females, 1971-1987.

Abstract: OBJECTIVE: Official rates of attempted suicide in Perth, in 1971-1972 and 1986-1987, were examined, with the aim of documenting changes in the age and sex distribution of persons who attempted suicide over the 15-year period. In addition a survey of all patients presenting to the Royal Adelaide Hospital between 1986 and 1988 aimed to determine whether or not the official figures accurately reflect the number of presentations for attempted suicide. DESIGN AND SETTING: Rates of attempted suicide were calculated from the Hospital Morbidity Data for hospitals in the Perth Statistical Division and from the Inpatient Separations Information System (ISIS) for hospitals in the Adelaide Statistical Division. Rates were expressed for each sex as annual age-specific rates per 100,000 population. The data were age-standardised by the direct method. A survey was completed of all patients presenting to the Royal Adelaide Hospital between 1986 and 1988 after attempted suicide. The findings were compared with the official figures for the Royal Adelaide Hospital and were used to estimate the actual rate of attempted suicide in the Adelaide Statistical Division. RESULTS: In Perth the rate of attempted suicide for males increased from 93 per 100,000 in 1971-1972 to 137 per 100,000 in 1986-1987. The increase was most striking in the age groups 15-19 and 40-44 years. The rates for females decreased from 214 per 100,000 to 195 per 100,000. In Adelaide, from 1986 to 1987, between one-fifth and one-third of persons who attempted suicide and presented to the Royal Adelaide Hospital were not recorded in the ISIS. In 1988, two-thirds were not recorded. We estimated that the real rate of attempted suicide for males in Adelaide was about 180 per 100,000 and for females was about 250 per 100,000. CONCLUSIONS: Our understanding of the epidemiology of attempted suicide is largely based on data which are now out of date. The Perth findings of a 47% rise in rate among males and a 9% fall among females suggest that attempted suicide is no longer a behaviour more associated with females than males. The Adelaide survey data demonstrate that official rates for attempted suicide underestimate the extent of the phenomenon in the community by a significant margin. An attempted suicide register is suggested as a method of overcoming this problem. Language: en

A comparison of Doppler ankle pressures and skin perfusion pressure in subjects with and without diabetes.

Abstract: Doppler ankle pressure measurements may be misleading in some patients because medial calcification has made the arteries of the leg incompressible. This problem is especially common in diabetics. Medical calcification that is not severe enough to make an artery clinically incompressible may cause an increased stiffness of the arterial wall that will limit the accuracy of Doppler ankle pressure measurements. A comparison of skin perfusion pressure, using an isotope technique, and Doppler ankle pressures was made in 226 subjects, diabetic and non-diabetic. Patients with incompressible arteries were excluded from the study. The slopes of the regression lines relating skin perfusion pressure to Doppler ankle pressure in diabetic and non-diabetic subjects were significantly different (P = 0.03). This result was consistent with the hypothesis that diabetic subjects have arteries that are less compressible than normal arteries and may make Doppler ankle pressure measurements in diabetic subjects misleading over the whole range of pressures recorded.

Treatment of collagen‐induced arthritis in rats with a monoclonal antibody against the α/β T cell antigen receptor

Abstract: A monoclonal antibody (MAb) to the alpha/beta T cell receptor (TCR alpha/beta), R73 MAb, completely blocked the induction of collagen-induced arthritis (CIA) in rats when the MAb was administered at the time of immunization with type II collagen. When administered after CIA had begun, the progression of the arthritis was suppressed significantly by R73 MAb treatment. The preventive and suppressive effects of R73 MAb on CIA were associated with the depletion of peripheral blood alpha/beta-positive T cells. These results indicate that alpha/beta-positive T cells play a role in the progression of existing CIA as well as in its induction.

Effect of cisapride on delayed gastric emptying in gastro-oesophageal reflux disease.

Abstract: Some patients with gastro-oesophageal reflux disease have delayed gastric emptying. This study investigates the effect of cisapride on gastric emptying in 34 patients with proved reflux and delayed gastric emptying of solids. They were enrolled in a double blind controlled crossover study. Placebo or cisapride (10 mg) tablets were given three times a day for three days followed by further assessment of gastric emptying. The protocol was repeated with the crossover tablet. Gastric emptying was assessed by a dual radionuclide technique. The percentage of a solid meal remaining in the stomach at 100 minutes (% R100 minutes) and the time taken for 50% of the liquid to empty (T50 minutes) were calculated and analysed by the Wilcoxon matched pairs signed ranks test and expressed as medians (ranges). For gastric emptying of solids the initial % R100 minutes (70 (60-100)%) was not significantly different from placebo (71 (35-100)%). After cisapride treatment a significant acceleration (p less than 0.001) in gastric emptying occurred (% R100 minutes, 50.5 (28-93)%). Similarly with gastric emptying of liquids, the initial T50 minute value was 26.5 (12-82) minutes, after placebo the value was 28 (11-81) minutes, but this was significantly accelerated with cisapride (p less than 0.03) to 22.5 (6-61) minutes. The acceleration in gastric emptying occurred in the proximal portion of the stomach for gastric emptying of both solids and liquids suggesting that this is the principal site of action of cisapride. We conclude that cisapride significantly accelerates gastric emptying of both solids and liquids in patients with gastro-oesophageal reflux disease and delayed gastric emptying.