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The effect of oxygen ingress into sour water containing dissolved sulfide on the production of sulfur and polysulfide (S-PS) and associated iron corrosion was investigated. Biotic (active SRB present), abiotic (autoclaved SRB present), and chemical (no bacteria present) conditions were compared. Under biotic conditions formation of S-PS was only seen at a high ratio of oxygen to sulfide (R(OS)) of 1 to 2.4. General corrosion rates increased 10-fold to 0.10 mm/yr under these conditions. Under abiotic and chemical conditions S-PS formation increased over the entire range of R(OS) with general corrosion rates reaching 0.06 mm/yr. Although general corrosion rates were thus highest under biotic conditions, biotically corroded coupons showed much less pitting corrosion. Maximum pit depth increased to 40-80 µm with increasing R(OS) for coupons incubated for 1 month under abiotic or chemical conditions but not for biotically incubated coupons (10 µm). This appeared to be related to the properties and size of the sulfur formed, which was hydrophobic and in excess of 10 µm under chemical or abiotic conditions and hydrophilic and 0.5 to 1 µm under biotic conditions. Hence, perhaps contrary to expectation, SRB lowered pitting corrosion rates under conditions of oxygen ingress due to their ability to respire oxygen and produce a less aggressive form of sulfur. Microbial control, which is usually required in sour systems, may be counterproductive under these conditions.

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BACKGROUND AND OBJECTIVES: A better understanding of the pathogenesis of chronic postsurgical pain is needed in order to develop effective prevention and treatment interventions. The objective of this study was to evaluate the incidence and risk factors for chronic postsurgical pain in women undergoing gynecologic surgery. METHODS: Pain characteristics, opioid consumption, and psychologic factors were captured before and 6 months after surgery. Analyses included univariate statistics, relative risks (RRs) and 95% confidence intervals (95% CIs), and modified Poisson regression for binary data. RESULTS: Pain and pain interference 6 months after surgery was reported by 14% (n = 60/433) and 12% (n = 54/433), respectively. Chronic postsurgical pain was reported by 23% (n = 39/172) with preoperative pelvic pain, 17% (n = 9/54) with preoperative remote pain, and 5.1% (n = 10/197) with no preoperative pain. Preoperative state anxiety (RR = 1.8; 95% CI, 1.1-2.8), preoperative pain (pelvic RR = 3.7; 95% CI, 1.9-7.2; remote RR = 3.0; 95% CI, 1.3-6.9), and moderate/severe in-hospital pain (RR = 3.0; 95% CI, 1.0-9.4) independently predicted chronic postsurgical pain. The same 3 factors predicted pain-interference at 6 months. Participants describing preoperative pelvic pain as "miserable" and "shooting" were 2.8 (range, 1.3-6.4) and 2.1 (range, 1.1-4.0) times more likely to report chronic postsurgical pain, respectively. Women taking preoperative opioids were 2.0 (range, 1.2-3.3) times more likely to report chronic postsurgical pain than those not taking opioids. Women with preoperative pelvic pain who took preoperative opioids were 30% (RR = 1.3; 95% CI, 0.8-1.9) more likely to report chronic postsurgical pain than those with preoperative pelvic pain not taking opioids. CONCLUSIONS: Preoperative pain, state anxiety, pain quality descriptors, opioid consumption, and early postoperative pain may be important predictors of chronic postsurgical pain, which require further investigation.

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OBJECTIVES: To measure the change in health-related quality of life (HRQOL) before and after gynaecologic surgery and to compare HRQOL to age-matched Canadian normative data. METHODS: This prospective observational cohort study consisted of a convenience sample of 460 women scheduled for elective gynaecologic surgery. Women underwent surgery for a variety of reasons, including cancer, menorrhagia/dysfunctional uterine bleeding, benign uterine masses, prolapse or urinary incontinence, and chronic pelvic pain syndromes. Women were recruited preoperatively and followed for six months after surgery. HRQOL questionnaires were completed preoperatively and at six weeks and six months postoperatively, using the SF-36, and compared between time points and against normative data. Analysis included univariate statistics, repeated measures ANOVA, paired t tests, and independent samples t tests. RESULTS: The mean age of women in the study cohort was 49 years (± 11); the majority were married, employed, had an education beyond high school, were overweight or obese, had a hysterectomy, and had an abdominal incision. Twenty-eight percent underwent surgery for cancer. General and mental health domains showed significant improvement between the preoperative and six-week postoperative assessments, while the remaining domains showed statistically significant declines. All but one (general health) of 10 outcomes saw significant improvements from the preoperative to the six-month follow-up assessment. Preoperatively, the surgical sample scored worse on all but one (role emotional) outcome than the normative data. By six months, domain scores were much closer to normative values. CONCLUSION: Health-related quality of life improved considerably from the preoperative period to six months postoperative in women who underwent gynaecologic surgery. When compared with normative data from age-matched women, the surgical sample reported significantly reduced HRQOL preoperatively and at six weeks following surgery, but by six months after surgery HRQOL had rebounded to the point of being comparable to age-matched peers.

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OBJECTIVE: To describe the use of oral phenazopyridine (Pyridium) prior to pelvic surgery to facilitate intraoperative confirmation of ureteric patency. MATERIALS AND METHODS: We performed a chart review of women given phenazopyridine preoperatively prior to pelvic surgery in a tertiary care centre between July 2004 and June 2005. The primary outcome was the cystoscopic observation of bilateral ureteric urine efflux. Secondary outcomes included the visualization of bladder mucosa during cystoscopy, postoperative complications, and urinary tract injury diagnosed postoperatively (i.e., missed intraoperatively). RESULTS: Pelvic reconstructive surgery requiring intraoperative cystoscopy was performed in 124 women. Bilateral ureteric patency and bladder mucosal integrity was confirmed in all cases. Phenazopyridine was well tolerated by all patients, and its use was unequivocally documented in 32 subjects whose chart was reviewed to determine postoperative course. Bladder mucosal appearance was unaltered. Dye continued to be excreted during prolonged procedures. Postoperatively, no ureteric injuries were subsequently diagnosed in any patients. The cost per patient of phenazopyridine ($0.29) is substantially lower than indigo carmine ($34.50). CONCLUSION: Preoperative oral phenazopyridine is an inexpensive and safe dye that assists effectively in the confirmation of ureteric patency when cystoscopy is planned during pelvic surgery.

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OBJECTIVES: To compare mid-trimester serum relaxin concentration (SRC) in primiparous women with or without pelvic floor dysfunction (PFD--stress urinary incontinence (SUI), genital prolapse). DESIGN: Nested observational cohort study. SETTING: Urogynecology clinic of affiliated University hospital. POPULATION: Primiparous women one to four years post-partum, who had, at time of index pregnancy, participated in a prospective observational study looking at mid-trimester serum relaxin and preterm delivery. METHODS: Relaxin had been obtained during the index pregnancy at 24 and 28 weeks. Primiparous women who had not given birth to a subsequent child were contacted and asked to return for a single visit assessing pelvic floor function. MAIN OUTCOME MEASURES: Pelvic Organ Prolapse Quantification system (POPQ) and Urogenital Distress Inventory (UDI-6). RESULTS: Fifty women participated, of whom 40 delivered vaginally. Seventeen (34%) women had prolapse and 23 (46%) had stress incontinence. Relaxin was slightly higher (not significantly) in women with PFD than in those without. Relaxin concentration declined significantly more rapidly from 24 to 28 weeks in incontinent women, after adjusting for baseline and obstetrical factors. CONCLUSIONS: In contrast to previous reports, mid-gestation relaxin tended to be higher and fall significantly faster in women with PFD. Acknowledging relaxin's effects on collagen turnover, our findings explore the association between childbirth and PFD.

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OBJECTIVE: To support the practitioner in the diagnosis of vaginal atrophy and in the management of the related symptoms. OPTIONS: The modalities of evaluation range from basic pelvic examination, examination of the vulva, and laboratory tests. OUTCOMES: A comprehensive approach to the detection of vaginal atrophy and a discussion of available therapeutic and nontherapeutic options. EVIDENCE: Published opinions of experts, supplemented by evidence from clinical trials, where appropriate. VALUES: The quality of the evidence is rated using the criteria described by the Canadian Task Force on the Periodic Health Examination. BENEFITS, HARMS, AND COSTS: Diagnosis of vaginal atrophy is often a challenge because women are unwilling to report symptoms, which have the potential to significantly decrease their quality of life. Increased clinical suspicion is the first step in the diagnosis of vaginal atrophy, which will prompt the initiation of safe therapies with proven efficacy. RECOMMENDATIONS: 1. Health-care providers should routinely assess postmenopausal women for the symptoms and signs of vaginal atrophy, a common condition that exerts significant negative effects on quality of life. (III-C) 2. Regular sexual activity should be encouraged to maintain vaginal health. (II-2B)3. Women experiencing recurrent urinary tract infections should be instructed that consumption of pure cranberry-lingonberry juice, rather than cranberry drink, will decrease their risk of urinary tract infections. (I-A) 4. Vaginal moisturizers applied on a regular basis have an efficacy equivalent to local hormone replacement for the treatment of local urogenital symptoms such as vaginal itching, irritation, and dyspareunia, and should be offered to women wishing to avoid use of hormone replacement therapy. (I-A) 5. Women experiencing vaginal atrophy can be offered any of the following effective vaginal estrogen replacement therapies: conjugated equine estrogen cream (I-A), a sustained-release intravaginal estradiol ring (I-A), or a low-dose estradiol tablet (I-A). 6. Although systemic absorption of estrogen can occur with local preparations, there is insufficient data to recommend annual endometrial surveillance in asymptomatic women using local estrogens. (III-C) 7. For menopausal women experiencing recurrent urinary tract infections and who have no contraindication to local hormone replacement, vaginal estrogen therapy should be offered. (I-A).

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