Use of contraception in women who present for termination of pregnancy in inner London

Objectives: To describe the contraceptive usage of women undergoing termination of pregnancy in order to identify problems with contraception, and therefore suggest ways in which contraceptive services can be improved.Design: Prospective study of attenders for NHS termination of pregnancy over a three month period.Setting: Community based assessment clinics for NHS termination of pregnancy in inner London.Subjects: Two hundred and sixty-nine women asking for assessment for NHS termination of pregnancy.Main Outcome Measures: Source of contraception, method used around time of conception, and problems experienced.Results: Respondents fell into three groups: those using contraception around the time they became pregnant; those who had ceased to use contraception; and those that had never used contraception. The method of contraception used by the majority of the first group was the condom and the main source of the method was the chemist shop. The second group had most commonly used oral contraceptives in the past and had ceased use in many cases as a result of side effects. The majority of the third group did not speak English and had limited knowledge of methods of contraception.Conclusions: High usage of chemists means women avoid service providers who could offer help and advice. Women were prepared to put themselves at risk of unwanted pregnancy rather than return for further help and the lack of knowledge about emergency birth control was of some concern. The needs of black and ethnic minority women requires detailed work to improve access and acceptability of contraceptive services.     

Experience with a new ureteral stent made of a biocompatible copolymer

A double-pigtail ureteral stent made from a biocompatible copolymer was designed for antegrade insertion with a new coaxial system. Thirty-eight of these stents were successfully placed in 33 patients. Of eight stents used for benign temporary indications, two (two patients) occluded prematurely. One of these patients had retained stone fragments, which caused the 10-F stent to occlude 4 months after balloon dilation of a midureteral stricture. The second patient had a ureteroconduit stricture that was dilated and stented, but mucus occluded the 10-F stent 5 days after insertion. In 25 of the patients, 30 stents were placed for ureteral obstruction due to malignant neoplasms. Three patients died with patent stents, while surviving patients with malignancies continue to have functioning stents, for an overall mean patency of 5.1 months in these patients. No problems related to stent migration or brittleness have been encountered.     

In vitro dissolution of gallstones with MTBE: correlation with characteristics at CT and MR imaging

The authors undertook a study to determine whether in vitro computed tomography (CT) or magnetic resonance (MR) imaging could enable the prediction of the outcome of gallstone dissolution with methyl tert-butyl ether (MTBE). In vitro CT and MR images were obtained of gallstones removed at surgery from 40 and 30 patients, respectively. The patterns of the gallstones seen on CT scans were categorized as dense, moderately dense, faint, isodense, rimmed, and laminated. Gallstones were categorized by maximal signal intensities seen on T1-weighted MR images. After imaging, gallstones underwent in vitro MTBE dissolution. CT appearances correlated well with dissolution rates. Greatest weight change was noted in gallstones with homogeneously faint and isodense patterns, and least weight change was seen in stones with a homogeneously dense pattern. Rimmed and laminated stones with foci of high attenuation dissolved significantly to 5% or less of the original weight, a finding indicating that such foci do not preclude dissolution. Dissolution rates correlated with attenuation values of homogeneous stones (r = .8) and of the rim portion of rimmed stones (r = .8). No correlation was found between T1-weighted signal intensities on MR images and MTBE dissolution rates.     

Assessment of the hemostatic effectiveness of human platelets treated with aminomethyltrimethyl psoralen and UV A light using a rabbit ear bleeding time technique

The photochemical aminomethyltrimethyl psoralen (AMT), in conjunction with UV A light (UVA), has been shown to inactivate human immunodeficiency virus-1 and model viruses in platelet suspensions under conditions that have only a minimal effect on in vitro platelet properties. A rabbit ear bleeding time technique was used to assess the hemostatic effectiveness of human platelet suspensions treated with AMT/UVA. New Zealand White rabbits were made thrombocytopenic by a combination of irradiation and heterologous antirabbit platelet antiserum. Reticuloendothelial function in these rabbits was suppressed by the intravenous administration of ethyl palmitate. The hemostatic function of 1- and 5-day-old human platelet suspensions (14.5% plasma) that had been treated on day 1 with 40 micrograms/mL AMT and 24 kJ/m2 UVA (1 x UVA) was evaluated by measuring microvascular bleeding times after a standard incision. Comparable bleeding times were observed after infusion with both control and AMT/UVA-treated platelets stored for either 1 or 5 days. With the transfusion of AMT/1 x UVA-treated platelets stored for 5 days, the mean (+/- SD) bleeding time was 156.3 +/- 39.2 seconds (n = 10). With untreated platelets (no AMT/no UVA), stored for 5 days, the mean bleeding time was 189.2 +/- 36.4 seconds (n = 10). Neither AMT nor 1 x UVA treatment alone influenced the observed bleeding times. In contrast, the hemostatic effectiveness of human platelet suspensions was diminished if they were exposed to three times the standard UVA dose (72 kJ/m2) on day 1 and stored for 4 more days, regardless of whether AMT was present, with the mean bleeding time increasing to 442.2 +/- 122.6 seconds (n = 15, AMT present) or 396.0 +/- 45.9 seconds (n = 10, AMT absent). These results are consistent with data obtained from in vitro studies and indicate that virucidal AMT/1 x UVA treatment does not influence platelet hemostatic function. However, the final conditions to achieve these results must be carefully controlled.     

The geographical assignment of cancer units: patient accessibility as an optimal allocation problem

The seminal report A Policy Framework for Commissioning Cancer Services provides the foundation for a major reorganisation of cancer service provision in England and Wales. One central recommendation of the report, the establishment of a tier of specialised cancer units in each Health Authority Region has raised the fundamental question of where those units are to be located. In particular, a declared objective of the report is for services to be planned to maximise their accessibility to patients. This paper demonstrates a classical method (location-allocation modelling) by which the accessibility criterion can be used to determine the optimal number, location and capacity of units for a given cancer site. The method is illustrated with reference to cervical cancer in Trent Health Authority Region. The implications of the method for the guidance of access-related decisions on the placement of cancer services are considered, and the wider relevance of the method to the organisation of service provision in other branches of medicine is suggested.