Biomedical subjects

Jason Abbott

Publications and source records attributed to Jason Abbott.

11 recordsLinked to original sources

PubMed2005

Nontyphoidal Salmonella from human clinical cases, asymptomatic children, and raw retail meats in Yucatan, Mexico.

BACKGROUND: We report the results of a 3-year Salmonella surveillance study of persons with diarrhea; asymptomatic children; and retail pork, poultry, and beef in Yucatan, Mexico. METHODS: Isolates were characterized according to serotype, antimicrobial susceptibility, and genetic relatedness with pulsed-field gel electrophoresis. RESULTS: Salmonella Typhimurium was the most common serotype found in ill humans (21.8% of isolates), followed by Salmonella Agona (21% of isolates). Salmonella Enteritidis was a minor serotype (4.2% of isolates). Asymptomatic children carried S. Agona (12.1% of isolates), Salmonella Meleagridis (11.6% of isolates), Salmonella Anatum (8% of isolates) and S. Enteritidis (5.8% of isolates). A high percentage of retail meat samples contained Salmonella; it was most commonly found in pork (58.1% of samples), followed by beef (54% of samples) and poultry (39.7% of samples). Resistance to oral drugs used for the treatment of salmonellosis was observed for ampicillin (14.6% of isolates were resistant), chloramphenicol (14.0% of isolates), and trimethoprim-sulfamethoxazole (19.7% of isolates). Resistance to ceftriaxone emerged in 2002 and was limited to the serotype S. Typhimurium. Twenty-seven percent of the isolates were resistant to nalidixic acid, and none were resistant to ciprofloxacin. Multidrug resistance was most common among isolates of serotypes S. Typhimurium and S. Anatum. Pulsed-field gel electrophoresis showed that strains found in retail meats were genetically identical to strains found in both asymptomatic children and ill patients. CONCLUSIONS: Our study found a high prevalence of Salmonella in retail meats and persons with enteric infection; many of these isolates were resistant to clinically important antimicrobials. A random selection of isolates from people and retail meat showed genetic relatedness, which suggests that, in Yucatan, considerable transfer of Salmonella occurs through the food chain.

Adolescent↗

PubMed2005

Transcervical sterilization.

The transcervical approach to permanent female sterilization has been studied for more than 150 years. Methods for accessing the tubes via this approach include blind, radiological and visual (hysteroscopic) techniques. Modalities for occluding the fallopian tubes include thermal, chemical and mechanical means. Some combination of the approach and the occlusive method define all known procedures. Initial attempts at transcervical sterilization were not widely adopted due to an inability to occlude the tube reliably, resulting in pregnancy and/or high morbidity from the procedure. Quinacrine sterilization is a procedure that is widely used in the developing world, but this has not been taken up by the developed world. There are limitations in diagnosing tubal occlusion with this technique. New methods for transcervical sterilization include the Essure and the Adiana procedures. These methods involve hysteroscopic placement of devices that rely on both mechanical occlusion and stimulation of tissue ingrowth to effect tubal occlusion. These new devices can be delivered to more than 90% of tubes, have very high success rates of pregnancy prevention (>99% in studies to date) and are acceptable to patients. Most importantly, they can be fitted under local anaesthesia in an ambulatory setting. The cost advantages of transcervical sterilization have not yet been investigated. It is possible that such a modality for permanent female sterilization may be demonstrated to be highly cost-effective.

Ambulatory Surgical Procedures↗

PubMed2004

Cost effectiveness analysis of laparoscopic hysterectomy compared with standard hysterectomy: results from a randomised trial.

OBJECTIVE: To assess the cost effectiveness of laparoscopic hysterectomy compared with conventional hysterectomy (abdominal or vaginal). DESIGN: Cost effectiveness analysis based on two parallel trials: laparoscopic (n = 324) compared with vaginal hysterectomy (n = 163); and laparoscopic (n = 573) compared with abdominal hysterectomy (n = 286). PARTICIPANTS: 1346 women requiring a hysterectomy for reasons other than malignancy. MAIN OUTCOME MEASURE: One year costs estimated from NHS perspective. Health outcomes expressed in terms of QALYs based on women's responses to the EQ-5D at baseline and at three points during up to 52 weeks' follow up. RESULTS: Laparoscopic hysterectomy cost an average of 401 pounds sterling (708 dollars; 571 euros) more (95% confidence interval 271 pounds sterling to 542 pounds sterling) than vaginal hysterectomy but produced little difference in mean QALYs (0.0015, -0.015 to 0.018). Mean differences in cost and QALYs generated an incremental cost per QALY gained of 267 333 pounds sterling (471 789 dollars; 380 437 euros). The probability that laparoscopic hysterectomy is cost effective was below 50% for a large range of values of willingness to pay for an additional QALY. Laparoscopic hysterectomy cost an average of 186 pounds sterling (328 dollars; 265 euros) more than abdominal hysterectomy, although 95% confidence intervals crossed zero (-26 pounds sterling to 375 pounds sterling); there was little difference in mean QALYs (0.007, -0.008 to 0.023), resulting in an incremental cost per QALY gained of 26 571 pounds sterling (46 893 dollars; 37 813 euros). If the NHS is willing to pay 30 000 pounds sterling for an additional QALY, the probability that laparoscopic hysterectomy is cost effective is 56%. CONCLUSIONS: Laparoscopic hysterectomy is not cost effective relative to vaginal hysterectomy. Its cost effectiveness relative to the abdominal procedure is finely balanced.

Cost-Benefit Analysis↗

PubMed2004

The eVALuate study: two parallel randomised trials, one comparing laparoscopic with abdominal hysterectomy, the other comparing laparoscopic with vaginal hysterectomy.

OBJECTIVE: To compare the effects of laparoscopic hysterectomy and abdominal hysterectomy in the abdominal trial, and laparoscopic hysterectomy and vaginal hysterectomy in the vaginal trial. DESIGN: Two parallel, multicentre, randomised trials. SETTING: 28 UK centres and two South African centres. PARTICIPANTS: 1380 women were recruited; 1346 had surgery; 937 were followed up at one year. Primary outcome Rate of major complications. RESULTS: In the abdominal trial laparoscopic hysterectomy was associated with a higher rate of major complications than abdominal hysterectomy (11.1% v 6.2%, P = 0.02; difference 4.9%, 95% confidence interval 0.9% to 9.1%) and the number needed to treat to harm was 20. Laparoscopic hysterectomy also took longer to perform (84 minutes v 50 minutes) but was less painful (visual analogue scale 3.51 v 3.88, P = 0.01) and resulted in a shorter stay in hospital after the operation (3 days v 4 days). Six weeks after the operation, laparoscopic hysterectomy was associated with less pain and better quality of life than abdominal hysterectomy (SF-12, body image scale, and sexual activity questionnaires). In the vaginal trial we found no evidence of a difference in major complication rates between laparoscopic hysterectomy and vaginal hysterectomy (9.8% v 9.5%, P = 0.92; difference 0.3%, -5.2% to 5.8%), and the number needed to treat to harm was 333. We found no evidence of other differences between laparoscopic hysterectomy and vaginal hysterectomy except that laparoscopic hysterectomy took longer to perform (72 minutes v 39 minutes) and was associated with a higher rate of detecting unexpected pathology (16.4% v 4.8%, P = < 0.01). However, this trial was underpowered. CONCLUSIONS: Laparoscopic hysterectomy was associated with a significantly higher rate of major complications than abdominal hysterectomy. It also took longer to perform but was associated with less pain, quicker recovery, and better short term quality of life. The trial comparing vaginal hysterectomy with laparoscopic hysterectomy was underpowered and is inconclusive on the rate of major complications; however, vaginal hysterectomy took less time.

Adult↗

PubMed2004

Laparoscopic excision of endometriosis: a randomized, placebo-controlled trial.

OBJECTIVE: To examine the effect on pain and quality of life for women with all stages of endometriosis undergoing laparoscopic surgery compared with placebo surgery. DESIGN: A randomized, blinded, crossover study. SETTING: A tertiary referral unit in a district general hospital. PATIENT(S): Thirty-nine women with histologically proven endometriosis completed the 12-month study. INTERVENTION(S): Women were randomized to receive initially either a diagnostic procedure (the delayed surgical group) or full excisional surgery (the immediate surgery group). After 6 months, repeat laparoscopy was performed, with removal of any pathology present. MAIN OUTCOME MEASURE(S): The end points were changes from baseline values of visual analogue pain scores, validated quality-of-life instruments (EQ-5D and SF-12), and sexual activity questionnaire scores. Patients and assessors of outcomes were blinded to the treatment-group assignment. RESULT(S): Significantly more of the 39 women operated on according to protocol reported symptomatic improvement after excisional surgery than after placebo: 16 of 20 (80%) vs. 6 of 19 (32%); chi(2)(1) = 9.3. Other aspects of quality of life were also significantly improved 6 months after excisional surgery but not after placebo. Progression of disease at second surgery was demonstrated for women having only an initial diagnostic procedure in 45% of cases, with disease remaining static in 33% and improving in 22% of cases. Nonresponsiveness to surgery was reported in 20% of cases. CONCLUSION(S): Laparoscopic excision of endometriosis is more effective than placebo at reducing pain and improving quality of life. Surgery is associated with a 30% placebo response rate that is not dependent on severity of disease. Approximately 20% of women do not report an improvement after surgery for endometriosis.

Adult↗

PubMed2004

Hysteroscopic training: the butternut pumpkin model.

Operative hysteroscopy involves significant hand-eye coordination, utilizing energy sources, video imaging, and the safe control of distending media. We describe a safe, effective, inexpensive, and reproducible method of developing the skills and hand-eye coordination for diagnostic and operative hysteroscopy. In this inanimate model, advanced surgical skills can be practiced, and realistic, simulated electrosurgery including resection of the endometrium and rollerball ablation can be performed.

Australia↗

PubMed2003

A double-blind randomized trial comparing the Cavaterm and the NovaSure endometrial ablation systems for the treatment of dysfunctional uterine bleeding.

OBJECTIVE: To compare two second-generation endometrial ablation systems in women with dysfunctional uterine bleeding (DUB) who want conservative surgical treatment. DESIGN: A double-blind, randomized trial. SETTING: A minimal access gynecological surgery unit in northeast England. PATIENT(S): Fifty-seven women diagnosed with DUB were recruited, with 55 undergoing surgery and completing 12-month follow-up. INTERVENTION(S): Thirty-seven women underwent a NovaSure endometrial ablation, and 18 had a Cavaterm endometrial ablation. Clinical and quality of life data were collected 6 and 12 months after treatment. MAIN OUTCOME MEASURE(S): Amenorrhea, menstrual change, quality of life, sexual activity, patient satisfaction, and procedure acceptability. RESULT(S): Amenorrhea, hypomenorrhea, eumenorrhea, and menorrhagia rates for the Cavaterm and Novasure groups at 12 months were 2/18 (11%) vs. 16/37 (43%); 11/18 (61%) vs. 10/37 (27%); 5/18 (27%) vs. 6/37 (16%); and 0/18 vs. 5/37 (13%), respectively. At 12 months, 83% and 92% of women were either satisfied or very satisfied in the Cavaterm or Novasure groups, respectively. There were no major complications in either group. CONCLUSION(S): Both the Cavaterm and the Novasure endometrial ablation systems are effective in reducing menstrual loss in women with DUB and achieve high rates of patient satisfaction. The Novasure system achieved a statistically significantly higher rate of amenorrhea in this study.

Adult↗

PubMed2003

In-vitro and in-vivo histochemical and thermal studies using a thermal balloon endometrial ablation system for varying treatment times.

BACKGROUND: To assess the immediate zone of thermal necrosis (ZTN) using an enzyme histochemical staining technique and serosal temperatures for the Cavaterm endometrial balloon ablation system for different treatment times. METHODS: A thermal balloon ablation was performed initially post- (n = 6) and subsequently pre-hysterectomy (n = 15). Eight to 12 tissue blocks from each uterus were sectioned and stained using diaphorase respiratory enzyme techniques. Patients in the in-vivo group had temperature measurements taken from four serosal points, a myometrial gradient profile, the balloon surface and the endocervical canal. RESULTS: The serosal temperature sensors did not demonstrate any rise in temperature above 44.1 degrees C. The mean temperature at the anterior wall, posterior wall, fundus and cornual areas was 37.1 (SD 1.3), 36.8 (SD 1.0), 37.4 (SD 1.8) and 36.7 degrees C (SD 1.0), respectively. The immediate mean maximum ZTN was greatest for the 15-min treatment time (3.1 mm, SD 1.5) compared to the 10- and 7-min treatment times (3.0 mm, SD 1.4 and 2.2 mm, SD 0.7, respectively). The maximum ZTN recorded was 5.6 mm. No full thickness injuries were demonstrated either histochemically or suggested by the temperature studies. CONCLUSIONS: This study confirms that Cavaterm thermal balloon ablation produces a reproducible thermal injury without evidence of serosal heating. Results suggest that the treatment time could be reduced to 10-min with no detrimental effect on the clinical outcomes. This hypothesis is currently being evaluated by clinical trials.

Female↗

PubMed2003

A randomised controlled trial comparing the Cavaterm endometrial ablation system with the Nd:YAG laser for the treatment of dysfunctional uterine bleeding.

OBJECTIVE: To compare the effectiveness of the Cavaterm thermal balloon endometrial ablation system with the Nd:YAG laser for the treatment of dysfunctional uterine bleeding. DESIGN: Randomised controlled trial. SETTING: Minimal access gynaecological surgery unit in a district general hospital. POPULATION: Seventy-two women with dysfunctional uterine bleeding requesting conservative surgical management of their condition. METHODS: Women with a normal endometrial biopsy and normal uterine cavity were randomly allocated to endometrial ablation by Cavaterm or Nd:YAG laser. Patients completed pre-operative and 6- and 12-month post-operative questionnaires assessing menstrual symptoms, quality of life, sexual activity and procedural satisfaction and acceptability. All patients received a single dose of gonadotropin-releasing hormone analogue one month pre-operatively and kept blinded to the procedure performed until after the 6-month assessment. MAIN OUTCOME MEASURES: The primary outcome measure was amenorrhoea rate. Secondary outcomes were effect on blood loss, quality of life, sexual activity, patient satisfaction and procedure acceptability. RESULTS: Seventy-two women were randomised. Amenorrhoea rates at 12 months in the Cavaterm and endometrial laser ablation groups were 29% vs 39% (P = 0.286), with combined amenorrhoea and hypomenorrhoea rates of 73% vs 69%, respectively. At 12 months, repeat surgery rates were higher in the endometrial laser ablation group (15% vs 12%, P = 0.395). Cavaterm was an acceptable procedure and 93% of patients satisfied or very satisfied at 12 months (95% endometrial laser ablation). Both treatments were associated with an increase from baseline in the SF-12 physical score (Cavaterm mean difference -3.9, 95% CI -7.9, 0.2, ns; endometrial laser ablation mean difference -5.1, 95% CI -9.5, -0.7, P = 0.003) and mental health score (Cavaterm mean difference -5.6, 95% CI -9.9, -1.3, P = 0.001; endometrial laser ablation mean difference -5.9, 95% CI -11.7, -0.2, P = 0.04). Patient's own assessment of health (EQ-5D VAS) improved from baseline in both groups (Cavaterm mean difference -7.6, 95% CI -13.9, -1.3, P = 0.02; endometrial laser ablation mean difference -5.4, 95% CI -14.9, 4.2, ns). EQ-5D index scores also improved (Cavaterm mean difference -0.06, 95% CI -0.2, 0.005, ns; endometrial laser ablation mean difference -0.17, 95% CI -0.3, -0.02, P = 0.02). There were no major complications in either group. CONCLUSIONS: The results with the Cavaterm thermal balloon endometrial ablation system are as good as those obtained with the Nd:YAG laser when used for the treatment of dysfunctional uterine bleeding in the short term. It results in a significant reduction in menstrual blood loss, patient satisfaction and improvement in patient quality of life. Larger studies with longer follow up are required to determine its place in the modern treatment of dysfunctional uterine bleeding.

Adult↗

PubMed2002

Pelvic pain scores in women without pelvic pathology.

STUDY OBJECTIVE: To assess the presence of and quantify pelvic pain in a group of women without demonstrable pelvic pathology as confirmed by laparoscopy. DESIGN: Prospective observational study (Canadian Task force classification II-2). SETTING: District general hospital. PATIENTS: One hundred forty-three consecutive women undergoing laparoscopy for sterilization, infertility investigation, or assessment of pelvic pain. INTERVENTION: Laparoscopy. MEASUREMENTS AND MAIN RESULTS: Women were asked to complete a questionnaire including a visual analog score for four different types of pelvic pain (dysmenorrhea, pelvic pain, dyspareunia, rectal pain) and three quality of life assessments. Forty-three women were excluded due to pelvic pathology. In the 100 remaining women, mean pain scores (maximum 10) were dysmenorrhea 3.77, pelvic pain 1.75, dyspareunia 1.54, and rectal pain 1.07. Quality of life assessment was no different from that in a healthy population in whom the instruments were validated. CONCLUSION: Pelvic pain, principally dysmenorrhea, is common in women of reproductive age. Pain scores may be used to compare treatments for pelvic pain and provide useful information for preoperative counseling.

Adolescent↗

PubMedDate not supplied

An evaluation of four tests used to ascertain Veres needle placement at closed laparoscopy.

STUDY OBJECTIVE: To determine the reliability of four commonly used tests to confirm the placement of the Veres needle during closed laparoscopy and their ability to determine other complications of entry. DESIGN: A prospective observational study (Canadian Task Force classification II-2). SETTING: A university-affiliated teaching hospital in Sydney, Australia. PATIENTS: Three hundred forty-five women undergoing closed laparoscopy using Veres needle peritoneal insufflation. INTERVENTIONS: The double click test, the hanging drop test, the aspiration test, and the initial five pressures at the time of insufflation following Veres needle placement were assessed for their sensitivity, specificity, and positive and negative predictive values for correct intraperitoneal placement of the needle and the presence or absence of any complication such as preperitoneal insufflation, omental emphysema, or visceral injury. MEASUREMENTS AND MAIN RESULTS: Complications occurred in 65 (18.8%) of 345 women, with preperitoneal insufflation in 19 (5.5%) of the 345, a superficial gastric injury in 1 (0.3%), and omental emphysema in 45 (13%). There was poor sensitivity and positive predictive values for preinsufflation tests. The first five pressures after commencement of insufflation were a sensitive predictor (79%) of complications, particularly preperitoneal insufflation (100% sensitivity for this complication). When two or more passes of the Veres were required, there was a significantly greater chance of preperitoneal insufflation (chi2 = 20.5, p <.0001). Preperitoneal insufflation was not reported when the first five successive insufflation pressures were less than 10 mm Hg. CONCLUSIONS: The double click, aspiration, and hanging drop tests provide very little useful information on the placement of the Veres needle at the time of closed laparoscopy. The initial gas pressures provide considerable information on the placement of the Veres needle, in particular the likelihood of preperitoneal insufflation. We conclude that the initial gas pressure is the only valuable measure to reflect correct intraperitoneal Veres needle placement.

Adult↗