On the effects of straight metallic jewellery on the specific absorption rates resulting from face-illuminating radio communication devices at popular cellular frequencies.

This paper presents simulated and measured phantom results for the possible effects that head worn jewellery may have on the relative levels of energy absorbed in the human head with cellular enabled mobile communication devices. The FDTD electromagnetic code used with simple and complex anatomical mathematical phantoms was used to consider the interactions of metallic jewellery, heads and representative sources at 900 and 1800 MHz. Illuminated metallic pins of different lengths were positioned in front of the face. Initially, a homogenous phantom was used to understand the relative enhancement mechanisms. This geometry allowed the results to be validated with the industry standard DASY4 robot SAR measurement system related to the CENELEC head. Jewellery pins were then added to an anatomically realistic head. The relative increase in the 1 g and 10 g SAR, due to a pin with a length 0.4lambda near the eyebrows of a complex, anatomically realistic head was approximately three times at 1800 MHz. Such pins increased the SAR averaged over a 1 g or 10 g mass by redistributing the energy absorbed inside the head and focusing this energy towards the area of the head nearest to the centre of the pin. Although, the pins increased the SAR, the SAR standards were not breached and the jewellery produced lower values than those of previous studies when the source was positioned close to the ear.

Prophylactic vs postoperative antibiotic use in complex septorhinoplasty surgery: a prospective, randomized, single-blind trial comparing efficacy.

OBJECTIVE: To compare the efficacy of prophylactic vs postoperative antibiotic use in complex septorhinoplasty and strengthen the evidence base for antibiotic use in nasal surgery. DESIGN: A randomized, prospective, single-blinded trial. One hundred sixty-four patients requiring complex septorhinoplasty surgery were recruited sequentially from the waiting lists of the 2 senior authors. Power was calculated at 80% at the 5% significance level. Patients randomized to the prophylactic arm of the study received three 1200-mg intravenous doses of amoxicillin-clavulanate, given at induction of anesthesia and at 6 and 12 hours postoperatively. Patients in the postoperative antibiotic arm received a 7-day course of 375 mg of amoxicillin-clavulanate 3 times a day. Patients allergic to penicillin were given erythromycin. Clinical and microbiological evidence of infection on the 10th postoperative day was categorized as either minor (vestibulitis) or major (nasal or septal cellulitis, septal abscess, secondary hemorrhage, or donor-site infection) infections. RESULTS: At follow-up, 6 (7%) of 82 patients in the prophylactic arm and 9 (11%) of 82 of patients in the postoperative arm showed evidence of infection. Most (80%) of infections were minor. There was no significant difference in infection rates between the prophylactic and postoperative arms on chi2 analysis (P = .42). All 164 patients completed the study on an intention-to-treat basis. CONCLUSION: We recommend the use of prophylactic antibiotics rather than empirical postoperative antibiotics for patients undergoing complex septorhinoplasty.

Preoperative localization of parathyroid adenomas: ultrasonography, sestamibi scintigraphy, or both?

Minimal access techniques are increasingly used to remove parathyroid adenomas. Such surgery depends on accurate preoperative localization but the selection of imaging modality remains controversial. We have reviewed the accuracy of ultrasonography, sestamibi scintigraphy and their combination in 48 cases of primary hyperparathyroidism. Ultrasound had a sensitivity of 64.3% (95% confidence interval 44.1-81.4) and positive predictive value (PPV) of 100% (81.5-100) for correct lateralization. Sestamibi had a sensitivity of 83.3% (69.8-92.5) and PPV of 87.1% (73.7-95.1). The simple combination of ultrasound with sestamibi had a sensitivity of 82.1% (63.1-93.9) and a PPV of 92.0% (74.0-99.0): little different from sestamibi alone. However, if the sestamibi result was disregarded in favour of ultrasonography in discordant cases, the sensitivity reached 96.4% (81.7-99.9) and the PPV was 100% (87.2-100). These results were not dependant on a learning curve or the size of adenoma.

Dipstick screening for urinary tract infection before arthroplasty: a safe alternative to laboratory testing?

We performed a prospective study on 247 consecutive patients attending our arthroplasty pre-admission clinic over six months, to compare the accuracy of dipstick urinalysis with the standard microbiological test for excluding urinary tract infection. There were 22 positive culture results and 43 positive dipstick results, with 16 true positives and 198 true negatives. Sensitivity was 72.7%, lower then the 88.0% figure for specificity. The positive predictive value was 37.2%, and the negative predictive value was 97.1%. Dipstick urinalysis is ideally suited to the busy pre-admission setting and would have resulted in a 90% reduction in the number of samples sent for laboratory analysis. In view of these results, we have changed our working practise from performing cultures to dipstick urinalysis on all patients prior to arthroplasty.

A novel method for replacement of a blocked fine bore nasogastric tube.

Nasogastric intubation is often difficult in patients with upper aero-digestive tract tumours. We present a new method for replacing obstructed fine-bore nasogastric tubes. This method eliminates the need for specialized equipment and skills, minimizes the risk of tracheal intubation and oesophageal trauma, and is better tolerated by patients.