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Biomedical subjects

J D Mason

Publications and source records attributed to J D Mason.

At least 19 recordsLinked to original sources
PubMed2001

Comparative practice patterns of emergency medicine physicians and pediatric emergency medicine physicians managing fever in young children.

BACKGROUND/OBJECTIVE: The management of fever in young children is a controversial topic. This study seeks to compare the management approaches between general emergency medicine physicians (GEMPs) and pediatric emergency medicine physicians (PEMPs) and correlate them to existing practice guidelines. DESIGN/METHODS: All charts of children age 3 to 36 months presenting with the complaint of fever at both a children's hospital emergency department (ED) and a general ED from June 1, 1998 to September 1, 1998; December 1, 1998 to April 1, 1999; and June 1, 1999 to September 1, 1999 were retrospectively reviewed. Fever was defined as >/=39 degrees C. Patients with a history of immunodeficiency, chronic illness, ventriculoperitoneal shunt, antibiotic use in the past 48 hours, or focal infection noted on examination were excluded. Data collected included focal exam findings, laboratory tests, diagnosis, treatment, and disposition. Variances from the practice guidelines were tabulated and compared. RESULTS: One thousand three hundred twenty-three eligible children met exclusion criteria and were seen by PEMPs; 755 were eliminated because of exclusion criteria (526 because of focal infection). Twenty-two (4%) of 568 remaining patients were admitted to the hospital. Two hundred twenty-eight eligible children were seen by GEMPs; 147 were excluded (109 because of focal infection). No patients were admitted to the hospital. PEMPs ordered more complete blood counts (324/568 vs 27/81), more blood cultures (321/568 vs 27/81), and more urine cultures (208/568 vs 20/81) than GEMPs. GEMPs ordered more chest radiographs and cerebrospinal fluid analyses than PEMPs; GEMPs ordered less complete blood counts, blood cultures, and urine cultures than PEMPs. GEMPs diagnosed more focal infections (109/228 vs 526/1323), and conflicted more often with the practice guidelines (66/79 vs 225/498) than PEMPs. Patients spent an average of 2.26 +/- 0.16 hours in the pediatric ED versus 3.0 hours +/- 0.18 hours in the general ED. CONCLUSIONS: Significant differences in the management of the young child with fever and no source exist between these two groups of physicians. These variations affect both cost and standard of care. Future studies assessing whether these strategies affect patient outcomes would further elucidate their clinical implication.

Bacterial Infections↗
PubMed2000

Community water fluoridation, bone mineral density, and fractures: prospective study of effects in older women.

OBJECTIVE: To determine whether fluoridation influences bone mineral density and fractures in older women. DESIGN: Multicentre prospective study on risk factors for osteoporosis and fractures. SETTING: Four community based centres in the United States. PARTICIPANTS: 9704 ambulatory women without bilateral hip replacements enrolled during 1986-8; 7129 provided information on exposure to fluoride. MAIN OUTCOME MEASURES: Bone mineral density of the lumbar spine, proximal femur, radius, and calcaneus plus incident fractures (fractures that occurred during the study) of vertebrae, hip, wrist, and humerus. RESULTS: Women were classified as exposed or not exposed or having unknown exposure to fluoride for each year from 1950 to 1994. Outcomes were compared in women with continuous exposure to fluoridated water for the past 20 years (n=3218) and women with no exposure during the past 20 years (n=2563). In women with continuous exposure mean bone mineral density was 2.6% higher at the femoral neck (0.017 g/cm(2), P<0.001), 2.5% higher at the lumbar spine (0.022 g/cm(2), P<0.001), and 1.9% lower at the distal radius (0.007 g/cm(2), P=0.002). In women with continuous exposure the multivariable adjusted risk of hip fracture was slightly reduced (risk ratio 0.69, 95% confidence interval 0.50 to 0.96, P=0.028) as was the risk of vertebral fracture (0.73, 0.55 to 0.97, P=0.033). There was a non-significant trend toward an increased risk of wrist fracture (1.32, 1.00 to 1.71, P=0.051) and no difference in risk of humerus fracture (0.85, 0.58 to 1.23, P=0.378). CONCLUSIONS: Long term exposure to fluoridated drinking water does not increase the risk of fracture.

Aged↗
PubMed1999

Alar haematoma.

We present two cases of alar haematoma. This is a very rare complication of nasal trauma, and only two cases have been described previously. One case presented late and did not undergo surgical drainage and has a persistent cosmetic deformity. We recommend early surgical drainage when possible.

Adult↗
PubMed1999

Twenty-four hour ambulatory nasal pH monitoring.

The nasal delivery of drugs, both for systemic and local use, is an expanding field with many drugs being delivered by this route. It is known that changes in pH can affect drug absorption but there is no data regarding intranasal pH over time. We present the results of 24-h ambulatory nasal pH monitoring in four subjects, each of whom had monitoring on two separate occasions. The apparatus consisted of a pH monitor with two electrodes, thus enabling us to take readings from 1 and 4 cm behind the anterior end of the inferior turbinate. Measurements were recorded every 6 s by the posterior electrode and every 30 s by the anterior electrode. The recording apparatus was worn around the subjects waist. Analysis of the results showed that there was no diurnal variation and no significant differences between the subjects. The mean pH from the anterior electrode was higher than that from the posterior (7.1 versus 6.6). The pH did not fluctuate with daily activities such as eating, drinking or sleeping. The results are interesting and may be of importance with regard to the design of formulations for nasal drug delivery systems.

Activities of Daily Living↗
PubMed1998

A systematic approach to the interpretation of computed tomography scans prior to endoscopic sinus surgery.

Computed tomography (CT) provides an excellent map for the sinus surgeon as well as providing information about the extent of disease and the presence of bony destruction. Surgeons need to be aware of the anatomical configuration of the sinuses and the presence of any structural changes such as a dehiscent lamina papyracea, asymmetric skull base, low level of posterior skull base or an Onodi cell, which place the patient at increased risk. Described here is a six-step guide to help the sinus surgeon avoid missing any of the radiologically important features.

Endoscopy↗
PubMed1997

Chitosan as a nasal delivery system: the effect of chitosan solutions on in vitro and in vivo mucociliary transport rates in human turbinates and volunteers.

In these studies, we examined the effect on mucociliary transport rates (MTR) of various 0.25% (w/v) chitosan solutions applied to human nasal tissue both ex vivo and in vivo. In the first study a range of chitosans with different molecular weights were applied to freshly amputated human nasal turbinates, and their effect on MTR was recorded. The transient inhibitory effect on turbinate MTR that was found for most of the chitosan preparations showed a marked dependence on the volume of chitosan solution applied and the molecular weight of the chitosan tested. The higher the molecular weight of the chitosan and the more chitosan applied, the longer the original MTR was depressed. A small scale human trial, investigating the effect of chitosan glutamate, on saccharin clearance times, was also undertaken. The study showed that a once daily application of a 0.25% solution of the chitosan for 7 days had no effect on either saccharin clearance times or nasal histology as examined by light microscopy.

Adult↗
PubMed1996

Effect of facial burns on the nasal mucosa.

In this study the nasal mucosa of patients who had recently sustained facial burns was examined endoscopically. The saccharin clearance test was performed as a measure of nasal mucociliary transport. All the patients had singed nasal hairs, but none had inflammatory changes extending beyond the nasal valve. In only one patient was the saccharin clearance prolonged beyond 20 min, and only one patient developed nasal obstruction postburn. This study shows that the nasal mucosa is resistant to damage when the face is burned, suggesting the nose is an efficient heat exchanger, and the nasal mucosa should preserve its capacity to absorb drugs.

Adult↗
PubMed1996

The evaluation of acute abdominal pain in children.

The infant or child that presents with abdominal pain must be evaluated with a careful history, physical examination, and selective laboratory studies. There are a few diagnoses that the emergency physician should always consider as "life threatening." In the event of any uncertainty in the diagnosis of conditions like appendicitis, pyloric stenosis, or intussusception, the child or infant should be observed carefully over time with appropriate laboratory/radiologic studies ordered to further delineate pathology. Ultrasound evaluation of children with abdominal pain continues to be one of the most valuable tools to help diagnose different conditions.

Abdominal Pain↗
PubMed1996

Client centred hypnotherapy in the management of tinnitus--is it better than counselling?

The aim of this study was to assess whether client centred hypnotherapy (CCH) which required three sessions with a trained therapist was superior to a single counselling session in reducing the impact of tinnitus. Patients were randomly allocated to receive either counselling (n = 42) or CCH (n = 44). The outcome measures were: tinnitus loudness match, subjective tinnitus symptom severity score, trend of linear analogue scale, request for further therapy and whether the patient had an impression of improvement in their tinnitus after treatment. CCH was no better than counselling in reducing the impact of tinnitus using the three quantative measures of tinnitus, and requests for further follow up. The only significant difference between the two therapies was that 20 (45.5 per cent) of the CCH group reported a general sense of improvement compared to six (14.3 per cent) in the counselling group, this is significant p < 0.01. The study did not demonstrate whether this was a genuine hypnotic effect or simply a response to the additional attention from the therapist.

Adult↗
PubMed1995

Raised ABR threshold after suction aspiration of glue from the middle ear: three case studies.

Between 1991 and 1993, 13 children (25 hearing ears) underwent recordings of the auditory brain stem response (ABR) under a general anaesthetic. The anaesthetic technique was similar for each child. Fourteen of these ears had fluid aspirated after myringotomy with insertion of grommets prior to the auditory brain stem response investigation. On subsequent hearing assessment six of these 14 ears (43 per cent) showed clear evidence of a threshold shift of 15 dB or greater. Eleven ears had either dry myringotomies or did not have a myringotomy prior to ABR and none of these showed evidence of a temporary threshold shift. Using Fisher's Exact probability test this difference is significant (p = 0.034). We feel it is important to report these observations so that unexpected high ABR thresholds following aspiration of glue are interpreted with caution.

Adolescent↗
PubMed1995

Measurement of small tissue volumes using Holden's apparatus.

A reproducible method for the estimation of volumes of small tissue samples was needed to allow comparison of the biological activity of tissue explants and to relate symptom improvement to procedures such as adenoidectomy or polypectomy. Holden's apparatus, which utilizes fluid displacement between two chambers, was compared to displacement in a 20 ml syringe. Two observers made four readings each on 20 tissue samples (range 0.37 to 4.70 ml) using both methods for comparison. A two-way analysis of variance for replicated data gave an F ratio of 0.6885 (df = 19; p > 0.8) for Holden's apparatus, and an F ratio of 1.4307 (df = 19; p > 0.1) for the 20 ml syringe. The standard error of the mean for repeated readings on the same sample by an observer was 0.001 ml for Holden's apparatus and 0.014 ml for the syringe method. For accurate estimation of small tissue volumes within 0.01 ml we recommend Holden's apparatus.

Adenoids↗
PubMed1995

Measurement of nasal mucociliary transport rates on the isolated human inferior turbinate.

The mucociliary transport rate was measured using sequential images of graphite particles moving on 17 isolated human inferior turbinates. These had been removed from 13 patients who had normal saccharin clearance tests on the day of surgery. The initial mean mucociliary transport rate was found to be 4.1 mm/min rising to 5.0 mm/min 2 h after harvesting. After 4 h it fell to 3.7 mm/min. Where the rate was measured at two different sites on the same turbinate (n = 4), there was a close correlation over 6 h (r = 0.95, P < 0.001). When the turbinates were exposed to an aqueous solution of adrenaline (1:10,000) or a 2.5% cocaine solution, the rate increased or decreased respectively by 100% and 58% but returned to within 10% of the initial level within 2 h. We believe that the isolated inferior turbinate can be considered a useful model for the study of mucociliary clearance and agents that may influence it.

Cocaine↗
PubMed1995

Streptokinase and facial haematoma.

We report two cases of facial haematoma following streptokinase therapy. This is an important complication as it can have fatal consequences. Early recognition and close monitoring are essential as emergency intervention may be required.

Aged↗