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A M Walters

Publications and source records attributed to A M Walters.

14 recordsLinked to original sources
PubMed2004

Implementation of a specialist-led service for the management of acute gallstone disease.

BACKGROUND: The 'gold standard' treatment for acute cholecystitis and biliary colic requiring hospital admission is urgent laparoscopic cholecystectomy. This is not routinely available in all hospitals. METHODS: A retrospective audit of emergency admissions with acute cholecystitis or biliary colic from January to December 2000 led to the development and implementation of a specialist-led protocol for the urgent management of acute gallstone disease. A second audit was carried out covering the 6 months after implementation. RESULTS: One hundred and fifty-eight patients were admitted with acute cholecystitis or biliary colic in the first audit period and 110 in the second interval. The rate of cholecystectomy at index admission increased from 37.3 to 67.3 per cent, at a median of 3 days after admission, and the conversion rate to open surgery fell from 32 to 12 per cent. Median hospital stay fell from 9 to 5.5 days, and the unplanned readmission rate decreased from 19.0 to 3.6 per cent. CONCLUSION: Urgent cholecystectomy for the management of acute gallstone disease is feasible and achievable in an acute services hospital with a specialist upper gastrointestinal team. It can lead to a reduced conversion rate, shorter hospital stay, fewer unplanned readmissions, an acceptable operating time and a low complication rate. The protocol is recommended for implementation in other hospitals.

Acute Disease↗
PubMed2004

Timing of urgent laparoscopic cholecystectomy does not influence conversion rate.

BACKGROUND: The optimal treatment of acute gallstone disease is urgent laparoscopic cholecystectomy, but there is confusion about the effect of delay in operation on conversion rates. Most reports suggest that delay beyond 3 or 4 days leads to a higher conversion rate. This study assessed the conversion rate in relation to the timing of laparoscopic surgery. METHODS: This institution operates a specialist-led protocol for the urgent management of all admissions with acute gallstone disease. Data were collected prospectively over 6 months. RESULTS: Between March and August 2002, 84 patients with acute gallstone disease underwent urgent laparoscopic cholecystectomy at the index admission with an overall conversion rate of 12 per cent. Four of 40 procedures carried out within 3 days of admission were converted, compared with six of 44 after 3 days. Five of 46 carried out within 4 days of admission were converted, compared with five of 38 after 4 days. There were no deaths and one common bile duct injury. CONCLUSION: As long as the procedure is carried out by experienced upper gastrointestinal surgeons working within a specialist-led protocol, the conversion rate for laparoscopic cholecystectomy can be as low as 12 per cent. The timing of urgent laparoscopic cholecystectomy has no impact on the conversion rate.

Adult↗
PubMed2000

The inferior vena caval conduit--a neglected technique in transplantation of the right cadaveric kidney?

A short right renal vein may reduce access or compromise optimal positioning during transplantation of the right cadaveric kidney. This difficulty could be overcome by using the inferior vena cava (IVC) as a venous conduit to lengthen the short right renal vein. This manoeuvre would also facilitate training by ensuring safe tension-free vascular anastomoses since the kidney can be lifted up a comfortable distance, thus improving exposure of the operative field. In a postal survey, only a third of UK renal transplant units utilised the IVC conduit. Despite 81.5% of units claiming that they harvest the IVC during organ retrieval, a 2-year retrospective audit revealed that only 4.3% of imported right kidneys had the IVC. The IVC remains a much under-utilised resource in the UK despite its potential benefit as a venous conduit in transplanting the right cadaveric kidney. We urge all retrieving surgeons to routinely harvest the IVC with right cadaveric kidneys during organ procurement.

Cadaver↗
PubMed1994

Effect of a model of canine jejunoileal orthotopic autotransplantation on jejunal and ileal transport of water and electrolytes.

Canine jejunoileal transplantation induces an early profuse watery diarrhea of uncertain etiology. Our aim was to determine the temporal effects of a canine model of jejunoileal autotransplantation (a model devoid of confounding effects of ischemia-reperfusion or immune rejection) on basal jejunal and ileal absorption of water and electrolytes to determine if impaired absorption is responsible for the diarrhea. Our hypothesis was that net absorption of water and electrolytes in an enterically isolated loop would decrease after jejunoileal transplantation. Four groups of dogs (N > or = 6) were prepared with 80-cm modified Thiry-Vella loops: group I, neurally intact jejunum; group II, autotransplanted jejunum; group III, neurally intact ileum; and group IV, autotransplanted ileum. The loops were perfused for 3 hr with 150 mM NaCl at 3 ml/min under fasted conditions; transit time through the loop was determined by bolus of a nonabsorbable marker. Dogs were studied on three separate days at one, two, eight, and nine weeks postoperatively. Net absorptive fluxes of water and electrolytes and transit times were similar (P > 0.05) between neurally intact and autotransplant groups (group I vs II and group III vs IV) at each time point. Ileal loops absorbed more than jejunal loops, and transit was slower in ileal loops (each P < 0.05). Our findings suggest that, despite the obligate disruption of extrinsic innervation, enteric (intrinsic) neural continuity, and lymphatic drainage that accompanies this canine model of jejunoileal autotransplantation, net basal absorptive function of water and electrolytes during the fasted state was not decreased nor was transit altered either in jejunum or ileum.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Absorption of simple nutrients from the in vivo neurally isolated canine jejunum and ileum.

BACKGROUND: The effects of intestinal transplantation on enteric absorptive function are not well understood. Our aim was to determine the effects of in situ isolation of the jejunoileum, a large animal model of jejunoileal autotransplantation, on absorption of simple nutrients from the jejunum and ileum separately. METHODS: Four groups of dogs were prepared with modified Thiry-Vella loops: group 1, neurally intact jejunum; group 2, neurally isolated jejunum; group 3, neurally intact ileum; and group 4, neurally isolated ileum. Intestinal loops were perfused with five different isosmolar solutions of NaCl alone, 30 mmol/L glucose, 2.5 mmol/L glycine, 2.5 mmol/L phenylalanine, and 5 mmol/L oleic acid at 1 to 2 weeks and 8 to 9 weeks after operation. RESULTS: Net absorption of water and electrolytes, glucose, glycine, phenylalanine, and oleic acid were not different statistically between neurally intact and neurally isolated intestinal loops at either time point. Ileal loops absorbed more than jejunal loops. CONCLUSIONS: Absorption of simple nutrients from the canine jejunum and ileum is not altered by this model of intestinal autotransplantation. These observations suggest that the extrinsic denervation that accompanies intestinal transplantation does not affect the transport systems for glucose, glycine, phenylalanine, or oleic acid.

Amino Acids↗
PubMed1992

The properties of cultured fetal human and rat brain tissue and its use as grafts for the relief of the parkinsonian syndrome.

Primary cultures were derived from human fetal ventral mesencephalon and cerebral cortex at 7-11 weeks gestation, and from fetal rat mesencephalon and cortex at embryonic day 14-15. Immunohistochemical analysis of the mesencephalic cultures using antibodies to tyrosine hydroxylase (TH) showed between 0.1-0.5% of human cells to be TH positive and 0.1-1% of rat cells to be TH positive. HPLC analysis of extracts from the cultures showed that they had the ability to synthesise and store dopamine. Implantation of the cultured human and rat mesencephalic tissue into a 6-hydroxydopamine rat model of Parkinson's disease produced marked recovery from amphetamine induced rotational asymmetry in the recipient rats, but no such recovery was observed following implantation of cortical cultures. Histological examination demonstrated the presence of surviving human mesencephalic and cortical grafts at least 6 months after implantation. Implants of cultured fetal rat tissue were less obviously but still significantly effective in these experiments. These rat tissue grafts were detectable for periods of at least 6-8 weeks by histological staining.

Animals↗
PubMed1992

Net absorption of water, electrolytes, glucose, and folate from the in vivo, neurally isolated canine jejunum.

This study was designed to determine the effects of neural isolation of the jejunoileum (a model of intestinal transplantation) on jejunal absorptive function and associated changes that might occur over time. Net absorption of a simple, balanced crystalloid solution perfused in an 80 cm enterically isolated jejunal loop was assessed in two groups of conscious dogs with neurally intact jejunal loops or neurally isolated jejunal loops. Experiments were conducted 2, 4, and 8 weeks after surgery during fasting and after feeding to determine temporal changes. Net absorption of water and electrolytes (sodium, potassium, and chloride), glucose, and folate and loop transit times were not different (p greater than 0.05) between groups at any time point despite the presence of ongoing watery diarrhea and weight loss (15% +/- 8% body weight) in the dogs with neurally isolated jejunoileum. The effects of neural isolation (extrinsic denervation and disruption of enteric neural continuity and lymphatic drainage) do not appear to decrease net absorptive capacity for water, electrolytes, simple sugars, or folate when evaluated between 2 and 8 weeks after neural isolation. The watery diarrhea and weight loss do not appear to be related to a jejunal secretory diarrhea. These findings may have important implications in the transplanted small intestine.

Animals↗
PubMed1991

Jejunal and ileal absorptive function after a model of canine jejunoileal autotransplantation.

The effects of intestinal transplantation on the physiologic functions of the gut are not well understood. Our aim was to determine the effect of a large animal model of small intestinal transplantation (disruption of all neural and lymphatic continuity) on selected absorptive functions of the jejunoileum. Seven dogs were studied before and at 1, 4, and 12 weeks after a model of jejunoileal autotransplantation, which avoids confounding factors of immune rejection, immunosuppression, and harvest ischemia. Jejunal function was assessed by quantitative [3H]-folate and D-xylose absorption and ileal function by quantitative 57Co-vitamin B12 absorption. The role of lymphatic continuity was assessed by fecal fat recovery following 5 days of a controlled, high fat diet (75 g/day). All dogs developed a profuse, watery diarrhea that persisted for 6 to 12 weeks and lost about 15% body weight; however, absorption of D-xylose, folate, and vitamin B12 was unaffected at any time point. Fat absorption postoperatively was only mildly abnormal (less than or equal to 8 g/day) at all time points in five of seven dogs despite complete lymphatic disruption. We concluded that jejunoileal autotransplantation does not markedly affect these specific jejunoileal absorptive functions. Fat absorption in most dogs surprisingly remains almost normal. Anatomic and physiologic consequences of intestinal transplantation do not appear to induce global abnormalities in all absorptive functions in the nonrejecting jejunoileum.

Absorption↗
PubMedDate not supplied

Multiple partners and partner choice as risk factors for sexually transmitted disease among female college students.

Multiple sexual partners and partner choice are believed to increase the risk of sexually transmitted disease (STD), but these behaviors had not previously been assessed outside of clinical populations. In this study, a cross-sectional survey among single, white, female students in their senior year of college was conducted to measure the association between behavioral risk factors and the acquisition of self-reported STDs during college. The usable response rate was 47.2% (n = 467). The combined prevalence of chlamydial infection, gonorrhea, genital herpes, human papillomavirus (HPV) infection, syphilis, and trichomoniasis during a 3.5-year period was 11.7%. There was a strong association between number of sexual partners and having an STD: those women with 5 or more sexual partners were 8 times more likely to report having an STD than those with only 1 partner, even after adjusting for age at first intercourse (odds ratio = 8.1; 95% confidence interval = 1.99, 32.64). The prevalence of a history of STDs increased with more causal partner choice and earlier age at first intercourse, but neither factor was independently associated with a history of STDs. Of the respondents, 23% always used condoms. Future research should focus on identifying ways of effectively changing high-risk sexual behavior.

Adult↗