Randomized trial to evaluate contraceptive efficacy, safety and acceptability of a two-rod contraceptive implant over 4 years in the Dominican Republic.

OBJECTIVE: Sino-implant (II) is a contraceptive implant that had a commodity price one-third of the competing products a decade ago. To make Sino-implant (II) more widely available, we conducted a trial to collect safety and efficacy data required for World Health Organization (WHO) prequalification, a quality standard allowing global donors to procure a pharmaceutical product. STUDY DESIGN: This was a randomized controlled trial allocating 650 participants to either Sino-implant (II) or Jadelle®. Participants were seen at 1 and 6 months, and then semiannually. The primary efficacy measure was the pregnancy Pearl Index [number of pregnancies per 100 women-years (WY) of follow-up] in the Sino-implant (II) group during up to 4 years of implant use. RESULTS: For the primary outcome, Sino-implant (II) had a 4-year Pearl Index of 0.74 (95% confidence interval, 0.36-1.37) compared to 0.00 (95% confidence interval, 0.00-1.04) for Jadelle®. The Sino-implant (II) pregnancy rate was significantly higher in the fourth year (3.54 per 100 WY) than in the first 3 years combined (0.18 per 100 WY; p <.001). Total levonorgestrel concentrations were equivalent between groups at month 12, but were 19%, 22% and 32% lower in the Sino-implant (II) group at months 24, 36 and 48, respectively (p <.001 at each time point). Safety and acceptability of the two products were similar, while providers documented significantly higher breakage rates during removal of Sino-implant (II) (16.3% vs. 3.1%; p <.001). CONCLUSION: Based on these results, WHO prequalified Sino-Implant (II) with a 3-year use label in June 2017, 2 years shorter than the 5-year duration of Jadelle®. IMPLICATIONS: WHO prequalification allows global donors to procure Sino-implant (II), which means women in many low resource countries will have greater access to highly effective and acceptable contraceptive implants. Our study noted important clinical differences, including shorter duration of high effectiveness with Sino-implant (II) when compared to the other available two-rod system, Jadelle®. Introduction strategies should include appropriate training on these differences.

Cohort study to evaluate efficacy, safety and acceptability of a two-rod contraceptive implant during third, fourth and fifth year of product use in China.

OBJECTIVE: Sino-implant (II) is a contraceptive implant approved for 4 years of use in China. We evaluated the contraceptive efficacy during the third, fourth and fifth year, and assessed additional pharmacokinetics (PK), safety, and acceptability endpoints. STUDY DESIGN: We enrolled a cohort of 255 current Sino-Implant (II) users entering their third year and a second cohort of 243 users entering their fourth year. We followed these two cohorts for 12 and 24 months, respectively. To characterize PK endpoints (i.e. levonorgestrel (LNG), sex hormone binding globulin and free LNG index) over 5 years, we collected blood samples in a subset of 50 participants we followed during the third, fourth and fifth year. We also enrolled small cohorts (n = 20) of Sino-implant (II) users entering their sixth month and second year and followed them each for up to 6 months. Our primary efficacy measures were the pregnancy Pearl Indices during Year 3 and 4. Secondary objectives included assessments of PK, safety, acceptability and efficacy in the fifth year. RESULTS: We recorded four pregnancies, with a higher pregnancy rate during Year 3 [1.34 (95% CI: 0.28-3.93)] than Year 4 [0.44 (95% CI: 0.01-2.47)] or Year 5 [0.00 (95% CI: 0.00-2.02)]. The overall pregnancy rate for the third, fourth and fifth years of product use was 0.63 per 100 WY; 95% CI: (0.17-1.62). Mean LNG concentrations remained well above 200 pg/mL (Year 3 = 280.9; Year 4 = 233.6; Year 5 = 270.6). Most participants (93.7%) described their bleeding pattern as acceptable. CONCLUSION: Sino-implant (II) is a highly effective contraceptive method in this population of Chinese women over 5 years. IMPLICATIONS: Sino-implant (II) is a highly effective contraceptive method with an estimated Pearl Index of less than 1% over the third, fourth and fifth years of use in a population of Chinese women of reproductive age.

Transition functions and correlation functions in the analysis of dynamic systems.

An understanding of the dynamic behavior of complex systems such as supercooled liquids requires a knowledge of the microscopic processes occurring in them. Correlation functions, which can be derived from experimental measurements of macroscopic properties or from computer simulations, cannot distinguish between particles that have never moved and those that have changed their position or state and then returned to the original one. Such a distinction can be obtained from the comparison of a correlation function with the transition function, i.e., the fraction of particles that have never moved up to time t. As the author demonstrates by an extension of his recently published results for the ferromagnetic Potts model [J. Chem. Phys. 124, 214508 (2006)], valuable insights into the microscopic behavior of a system can be obtained from such a comparison. A generalization of the transition function to a first passage function can provide useful extra insights.

Steroid hormones for contraception in men.

BACKGROUND: Male hormonal contraception has been an elusive goal. Administration of sex steroids to men can shut off sperm production through effects on the pituitary and hypothalamus. However, this approach also decreases production of testosterone, so 'add-back' therapy is needed. OBJECTIVES: To summarize all randomized controlled trials of male hormonal contraception. SEARCH STRATEGY: We searched the computerized databases CENTRAL, MEDLINE, EMBASE, POPLINE, and LILACS (each from inception to March 2006) for randomized controlled trials of hormonal contraception in men. We wrote to authors of identified trials to seek unpublished or published trials that we might have missed. SELECTION CRITERIA: We included all randomized controlled trials in any language that compared a steroid hormone with another contraceptive. We excluded non-steroidal male contraceptives, such as gossypol. We included both placebo and active-regimen control groups. All trials identified included only healthy men with normal semen analyses. DATA COLLECTION AND ANALYSIS: Azoospermia (absence of spermatozoa on semen examination) was the primary outcome measure. Data were insufficient to examine pregnancy rates and side effects. MAIN RESULTS: We found 30 trials that met our inclusion criteria. The proportion of men who achieved azoospermia varied widely in reports to date. A few important differences emerged from these trials: levonorgestrel implants combined with injectable testosterone enanthate (TE) were more effective than levonorgestrel 125 microg daily combined with testosterone patches; levonorgestrel 500 mug daily improved the effectiveness of TE 100 mg injected weekly; desogestrel 150 mug was less effective than desogestrel 300 mug (with testosterone pellets); testosterone undecanoate (TU) 500 mg was less likely to produce azoospermia than TU 1000 mg (with levonorgestrel implants); norethisterone enanthate 200 mg with TU 1000 mg led to more azoospermia when given every 8 weeks versus 12 weeks; four implants of 7-alpha-methyl-19-nortestosterone (MENT) were more effective than two MENT implants. Several trials showed promising efficacy in terms of percentages with azoospermia. Three examined desogestrel and testosterone preparations or etonogestrel (metabolite of desogestrel) and testosterone, and two examined levonorgestrel and testosterone. AUTHORS' CONCLUSIONS: No male hormonal contraceptive is ready for clinical use. Most trials were small exploratory studies. As a result, their power to detect important differences was limited and their results imprecise. In addition, the definition of oligozoospermia has been imprecise or inconsistent. To avoid bias, future trials need more attention to the methodological requirements for randomized controlled trials. More trials with adequate power would also be helpful.

Nonexponential relaxation and fragility in a model system and in supercooled liquids.

Among the outstanding problems in the theory of supercooled liquids are the reasons for the rapid increase in their viscosity and relaxation times as the temperature is lowered towards the glass transition temperature Tg, the nonexponential time dependence of the relaxation, and the possible connection between these two properties. The ferromagnetic Potts model on a square latice is a simple system that is found to exhibit these properties. Our calculations show that in this system the connection between them is associated with the dependence on temperature and time of the average environment of the sites. Some of the consequences of this for understanding the behavior of supercooled liquids are discussed.

Strategies to improve adherence and acceptability of hormonal methods for contraception.

BACKGROUND: Worldwide, hormonal contraceptives are among the most popular reversible contraceptives in current use. Despite their high theoretical effectiveness, typical use results in much lower effectiveness. In large part, this disparity reflects difficulties in adherence to the contraceptive regimen and low rates for long-term continuation. OBJECTIVES: To determine the effectiveness of ancillary techniques to improve adherence to, and continuation rates of, hormonal methods of contraception. SEARCH STRATEGY: We searched computerized databases for randomized controlled trials (RCTs) comparing client-provider interventions with standard family planning counseling. Sources included CENTRAL, MEDLINE, EMBASE, POPLINE, LILACS, and PsycINFO. SELECTION CRITERIA: Randomized controlled trials (RCTs) of an intensive counseling technique or client-provider intervention versus routine family planning counseling. Interventions included group motivation; structured, peer, or multi-component counseling; and intensive reminders of appointments. Outcome measures were discontinuation, reasons for discontinuation, number of missed pills and on-time injections, and pregnancy. DATA COLLECTION AND ANALYSIS: The primary author evaluated all titles and abstracts from the searches to determine eligibility. Two authors independently extracted data from the included studies. With RevMan 4.2, we calculated the odds ratio for all dichotomous outcomes and the weighted mean difference for continuous data. The studies were so different that we could not conduct a meta-analysis. MAIN RESULTS: We found six RCTs; only one showed a statistically significant benefit of the experimental intervention. In that trial, women who received repeated, structured information about the injectable contraceptive depo-medroxyprogesterone acetate (DMPA) were less likely to have discontinued the method by 12 months (OR 0.27; 95% CI 0.16 to 0.44) than were women who had routine counseling. The intervention group was also less likely to discontinue due to menstrual disturbances. In another study, the intervention group was less likely to discontinue due to dissatisfaction with the contraceptive method, but overall continuation was not affected. AUTHORS' CONCLUSIONS: Most studies to date have shown no benefit of strategies to improve adherence and continuation. These trials have important limitations, however. Two had small sample sizes, several had high losses to follow-up, and the intervention and its intensity varied across the studies. High-quality research is a priority, since adherence and continuation are fundamentally important to the successful use of hormonal contraceptives.

Spermicide used alone for contraception.

BACKGROUND: Spermicides have been used as contraceptives for thousands of years. Despite this long use, only recently have studies examined the comparative efficacy and acceptability of these vaginal medications. Spermicides contain an active ingredient (most commonly nonoxynol-9) and a formulation used to disperse the product, such as foam or vaginal suppository. OBJECTIVES: This review examined all known randomized controlled trials of a spermicide used alone for contraception. SEARCH STRATEGY: We searched the following computerized databases from inception to July 2004 for randomized controlled trials of spermicides for contraception: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, POPLINE, LILACS, and EMBASE. We examined the reference list of each trial found as well as that of review articles and textbook chapters. SELECTION CRITERIA: We included any trial of a commercial product used alone for contraception. Each included trial must have provided sufficient information to determine pregnancy rates. We located reports from 14 trials. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted information from the trials identified. We did not conduct a meta-analysis, since most trials had large losses to follow-up. We entered the data into tables and presented the results descriptively. MAIN RESULTS: In the largest trial to date, the gel (Advantage S) containing the lowest dose of nonoxynol-9 (52.5 mg) was significantly less effective in preventing pregnancy than were gels with higher doses of the same agent (100 mg and 150 mg). Probabilities of pregnancy by six months were 22% for the 52.5 mg gel, 16% for the 100 mg dose, and 14% for the 150 mg dose. In the same trial, the three different vehicles with 100 mg of nonoxynol-9 had similar efficacy. Interpretation of these figures is limited, since 39% of participants discontinued the method or were lost from the trial. Few important differences in efficacy emerged in other trials. AUTHORS' CONCLUSIONS: The probability of pregnancy varied widely in reported trials. A gel containing nonoxynol-9 52.5 mg was inferior to two other products tested in the largest trial. Aside from this finding, personal characteristics and behavior of users may be more important than characteristics of the spermicide products in determining the probability of pregnancy. Gel was liked more than the film or vaginal suppository in the largest trial. Spermicide trials have the dual challenges of difficult recruitment and high discontinuation rates; the latter threatens trial validity.

Simple model for ac ionic conduction in solids.

We present a model for the ac conduction in ionically conducting solids that takes into account, in a simple way, the interaction between carriers. The Coulomb force forms an "ionic atmosphere" that exerts a restoring force on a central ion, whose motion corresponds to an overdamped oscillator. We consider the effect of the relaxation of the ionic atmosphere by introducing an additional equation for the displacement of the potential toward the particle position. The general behavior of the ac conductivity can be understood in terms of two types of motions: motion of the bound ion at high frequencies determined by microscopic friction, and a much slower motion coupled to the surrounding carriers relaxation at low frequencies.

Management of the carotid artery in paraganglioma surgery.

Paragangliomas can be challenging to even the most experienced surgeon. Injuries to the carotid artery are not uncommon. To avoid injury, a careful preoperative assessment of the size and extent of the tumor and its relation to the internal carotid artery, external carotid artery, and common carotid artery is important for planning the procedure. For more extensive tumors, it is often helpful to have a multidisciplinary team available to handle all potential issues and complications.

Minimal incision abdominal aortic aneurysm repair.

PURPOSE: The use of a limited incision for abdominal aortic aneurysm (AAA) repair was evaluated, and its outcome was analyzed in comparison to laparoscopic-assisted and standard open repair. METHODS: Eleven patients who had an AAA that required a tube graft underwent minimal incision (MINI) repair. The procedure consisted of a standard endoaneurysmorrhaphy performed through an 8- to 10-cm minilaparotomy. Clinical characteristics, in-hospital outcomes, and total in-hospital charges for this procedure were then compared with those of comparative groups of patients who had undergone repair of AAA by means of a laparoscopic-assisted (LAP) approach or a standard open (OPEN) technique. RESULTS: MINI repair was successfully completed in all 11 patients. Patients in the three groups were comparable for age, sex, risk factors, and aortic dimensions. The mean values for operative time, blood loss, length of hospital stay, and total hospital charges for the three comparison groups were: 129. 7 minutes (MINI) vs. 244.8 minutes (LAP)*, 209.9 minutes (OPEN)*; 522.7 mL (MINI) vs. 1214.7 mL (LAP), 1795.8 mL (OPEN)*; 5.18 days (MINI) vs. 18.7 days (LAP), 17.4 days (OPEN); $22,692 (MINI) vs. $59, 922 (LAP)*, $62,324 (OPEN)* (*P <.05). Local complications occurred in 18.2% of patients who underwent MINI repair, 23.5% of patients who underwent LAP repair, and 29.7% of patients who underwent OPEN repair (P = not significant). Patients undergoing minilaparotomy demonstrated decreased compromise of gastrointestinal function, with a decreased need for postoperative fluid resuscitation (6799.7 mL [MINI], 7781.8 mL [LAP] vs. 11061.1 mL [OPEN]*) and shortened nasogastric tube decompression (1.6 days [MINI], 1.5 days [LAP] vs. 4.1 days [OPEN]*; *P <.05). CONCLUSION: MINI repair is a technically feasible technique that combines the benefits of minimally invasive surgery with those of conventional open repair with few, if any disadvantages. Facility of the procedure, combined with the potential cost benefits, encourages further study for consideration of this technique as a viable alternative for the management of AAAs.

Warfarin anticoagulation in the perioperative period: is it safe?

This study was undertaken to determine if warfarin anticoagulation could be safely continued during surgery and in the perioperative period. An animal model was followed by a prospective human study of all patients on heparin or warfarin at the time of surgery. Twenty-four rabbits underwent laparotomy, during which a controlled liver injury was created and repaired. Group 1 (Warf) was anticoagulated with warfarin to raise the mean international normalization ratio (INR) to 2.5-3.0. Group 2 (Hep) was anticoagulated with heparin to raise the activated partial thromboplastin time to 1.5-2.0 times control. The heparin was then stopped 6 hr prior to surgery and resumed 6 hr postoperatively without a bolus. Group 3 (control) was not anticoagulated and received saline infusion. For the human study, data were collected on 40 patients undergoing 50 operations from October 1996 to January 1998. The results of this study reveal that (1) bleeding was less in the group anticoagulated with warfarin throughout surgery in the animal model, (2) bleeding complications were less in the patients continued on warfarin through surgery than those on heparin (3) older patients may have an increased risk of bleeding, and (4) an INR of >3 at the time of surgery may increase the risk of bleeding.

Relationship of protamine dosing with postoperative complications of carotid endarterectomy.

Protamine sulfate (PS) neutralization of heparin (HEP) given during carotid endarterectomy (CEA) has been previously associated with an increased postoperative stroke rate. Dosing regimens of PS have varied in previous studies. The accuracy of PS dosing and its effect on postoperative complications was analyzed. The medical records of all patients undergoing elective CEAs from January 1993 to June 1996 in our institution were reviewed. A hematoma was defined as either an event requiring return to the operating room or when repeatedly identified in the medical record. The accuracy of dosing PS was determined utilizing a formula calculating the logarithmic exponential decay of HEP, which determined the residual HEP at the time of PS dosing. An ideal PS dose was then calculated and compared to the dose given. Statistical analyses was performed using a Fisher's exact test as well as the Student's t-test. Four hundred-seven CEAs were performed in 365 patients. There were 10/407 (2.5%) postoperative strokes (STROKE) and 11/407 (2.7%) hematomas, 3 of which required reoperation. Results indicate that (1) the administration of PS significantly reduced the incidence of postoperative hematoma; (2) there appears to be an association between the administration of PS and STROKE; (3) the inaccuracy in dosing PS appears to be based on a decision to dose PS to the total HEP given rather than the residual HEP on board at the time of neutralization. The effect of PS overdosing is unclear, but it may play a role in STROKE.

Perioperative predictors of colonic ischemia after ruptured abdominal aortic aneurysm.

PURPOSE: Colonic ischemia and colonic resection occur frequently after ruptured abdominal aortic aneurysm (rAAA). The purpose of this study was to identify the perioperative risk factors that might help to determine earlier in the postoperative period which patients are at risk for colonic ischemia and colonic resection. METHODS: The medical records of the 43 patients who underwent repair of rAAA from January 1989 to November 1997 were reviewed. The data were reviewed for the following factors: acidosis, pressor agents, lactate levels, guaiac status, cardiac index, coagulopathy, early postoperative bowel movement, the lowest intraoperative pH level, the temperature at the conclusion of the case, the location and duration of aortic cross clamping, the amount of fluid boluses administered after surgery, the amount of packed red blood cells administered during the case, and the average systolic blood pressure at admission and during surgery. Univariate analysis was performed with Fisher exact test, chi2 test, and Student t test. Multivariate analyses also were performed with the variables that were found to be significant on the univariate analysis. RESULTS: Thirteen of the 43 patients (30. 2%) had colonic ischemia, and seven of the 13 underwent colonic resection (53.8%). The overall mortality rate was 51.2% (22/43) five of the deaths were intraoperative and excluded from the study. In a comparison of the patients who had colonic ischemia with those who did not, statistically significant differences were found in the following variables: average systolic blood pressure at admission 90 mm Hg or less, hypotension of more than 30 minutes' duration, temperature less than 35 degreesC, pH less than 7.3, fluid boluses administered after surgery 5 L or more, and packed red blood cells 6 units or more. Multivariate analysis indicated that the number of these variables present correlated significantly with the positive predicted probability of colonic ischemia occurring. No patient with two factors or fewer had an ischemic bowel, and the positive predictive probability of colonic ischemia for those patients with six factors was 80%. CONCLUSION: The results of this study show that: (1) colonic ischemia after rAAA may be predicted with the presence of two or more specific perioperative factors, (2) the lack of a guaiac-positive bowel movement may be misleading for the early diagnosis of colonic ischemia, and (3) more than 50% of the patients with colonic ischemia will require a colonic resection. We recommend that any patient with rAAA with more than two perioperative factors undergo sigmoidoscopy every 12 hours after surgery for 48 hours to rule out colonic ischemia without waiting for early or guaiac-positive bowel movement.

Laparoscopically assisted abdominal aortic aneurysm repair: first 20 cases.

PURPOSE: Laparoscopic surgery decreases postoperative pain, shortens hospital stay, and returns patients to full functional status more quickly than open surgery for a variety of surgical procedures. This study was undertaken to evaluate laparoscopic techniques for application to abdominal aortic aneurysm (AAA) repair. METHODS: Twenty patients who had AAAs that required a tube graft underwent laparoscopically assisted AAA repair. The procedure consisted of transperitoneal laparoscopic dissection of the aneurysm neck and iliac vessels. A standard endoaneurysmorrhaphy was then performed through a minilaparotomy using the port sites for the aortic and iliac clamps. Data included operative times, duration of nasogastric suction, intensive care unit days, and postoperative hospital days. Pulmonary artery catheters and transesophageal echocardiography were used in seven patients. For these patients data included heart rate, pulmonary artery systolic and diastolic pressures, mean arterial pressure, central venous pressure, pulmonary capillary wedge pressure, cardiac index, and end diastolic area. Data were obtained before induction, during and after insufflation, during aortic cross-clamp, and at the end of the procedure. RESULTS: Laparoscopically assisted AAA repair was completed in 18 of 20 patients. Laparoscopic and total operative times were 1.44 +/- 0.44 and 4.1 +/- 0.92 hours, respectively. Duration of nasogastric suction was 1.3 +/- 0.7 days. Intensive care unit stay was 2.2 +/- 0.9 days. The mean length of hospital stay was 5.8 days excluding three patients who underwent other procedures. There were two minor complications, one major complication (colectomy after colon ischemia), and no deaths. For the eight patients who had intraoperative transesophageal echocardiographic monitoring, no changes were noted in heart rate, pulmonary artery systolic pressure, pulmonary capillary wedge pressure, and cardiac index. Pulmonary artery diastolic pressure and central venous pressure were greatest during insufflation without changes in end-diastolic area. Volume status, as reflected by end-diastolic area and pulmonary capillary wedge pressure, did not change. CONCLUSIONS: Laparoscopically assisted AAA repair is technically challenging but feasible. Potential advantages may be early removal of nasogastric suction, shorter intensive care unit and hospital stays, and prompt return to full functional status. The hemodynamic data obtained from the pulmonary artery catheter and transesophageal echocardiogram during pneumoperitoneum suggest that transesophageal echocardiography may be sufficient for evaluation of volume status along with the added benefit of detection of regional wall motion abnormalities and aortic insufficiency. Further refinement in technique and instrumentation will make total laparoscopic AAA repair a reality.

Utility of transesophageal echocardiography and pulmonary artery catheterization during laparoscopic assisted abdominal aortic aneurysm repair.

BACKGROUND: Advanced laparoscopic procedures are more commonly performed in elderly patients with cardiac disease. There has been limited data on the use of pulmonary artery catheters (PAC) and transesophageal echocardiography (TEE) to monitor hemodynamic changes. METHODS: We prospectively studied eight patients undergoing laparoscopic assisted abdominal aortic aneurysm repair. All patients had a PAC and all but one had an intraoperative TEE. Data included heart rate (HR), temperature (temp), pulmonary artery systolic (PAS) and diastolic (PAD) pressures, mean arterial pressure (MAP), central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP), cardiac index (CI), mixed venous oxygen saturation (MVO2), and oxygen extraction ratio (O2Ex) and was obtained prior to induction, during insufflation, after desufflation, during aortic cross-clamp, and at the end of the procedure. End diastolic area (EDA), a reflection of volume status, was measured on TEE. ANOVA was used for data analysis. RESULTS: No changes were noted in HR, temp, PAS, PCWP, CI, MVO2, and O2Ex. PAD and CVP were greater during insufflation compared with baseline and aortic cross-clamp without associated changes in EDA. MAP was higher at baseline compared with all other times during the procedure. CONCLUSIONS: Insufflation increased PAD and CVP. However, volume status as suggested by EDA and PCWP did not change. These data question the reliability of hemodynamic measurements obtained from the PAC during pneumoperitoneum and suggest that TEE may be sufficient for evaluation of volume status along with the added benefit of timely detection of ventricular wall motion abnormalities.

Elastin degradation products induce adventitial angiogenesis in the Anidjar/Dobrin rat aneurysm model.

BACKGROUND: Infusion of the abdominal aorta with pancreatic elastase induces aneurysms in a rat model (Anidjar/Dobrin). Because elastolysis liberates elastin degradation products (EDPs), the present experiment was carried out to test the hypothesis that an EDP alone could induce features of aneurysm disease. METHODS: The EDP val/gly/val/ala/pro/gly (VGVAPG), elastase, or saline solution was infused into infrarenal aorta (n = 4/group). After 1 week aortic diameters were measured, and the tissues were prepared for histologic examination. Adventitial capillaries (vessels per high-power field) were counted over a standardized preparation of aorta. Wall thickness was measured by means of computer-aided planimetry. RESULTS: There was an increase of greater than 100-fold in mean vessels per high-power field in aortas receiving VGVAPG or elastase versus saline controls (4.10 +/- 0.68 SEM or 4.48 +/- 0.49 SEM versus 0.03 +/- 0.03 SEM, respectively, p < 0.05). The VGVAPG-perfused group had a 26% +/- 4% SEM increase in diameter from baseline that was statistically significant (p < 0.01), but the aortas did not reach aneurysmal dimensions. CONCLUSIONS: Although no aneurysms occurred at 1 week after the infusion of EDP, the results demonstrate that the EDP VGVAPG can induce a characteristic feature of aneurysm disease. The model permits study of the earliest stages of experimental aneurysm formation and raises interesting questions regarding the role of the vasa vasorum in this pathologic process.

Multiple idiopathic arterial aneurysms in children: a case report and review of the literature.

A 6-year-old boy from China presented initially at 2 years of age with a pulsatile mass in his right antecubital fossa. He was not fully evaluated until the age of six years, when pan-angiography and computed axial tomography scan revealed multiple aneurysms of his right brachial artery, right radial artery aneurysms, an infrarenal aortic aneurysm, and a right internal carotid artery aneurysm in the region of the cavernous sinus. The patient underwent uneventful repairs of both the abdominal aortic aneurysm and the multiple aneurysms of the right arm. Pathologic evaluation was significant for medial fibrosis of the arterial wall with decreased and disordered elastin fibers. Review of the previously reported cases in children indicate the upper extremity arteries are involved in 92% of patients, the aortoiliac region in 92% of patients, and the renal/mesenteric vessels in 77% of cases. Lower extremity and cerebrovascular arteries are involved to a lesser extent. Children with peripheral aneurysms should have pan-angiography performed before treatment is begun. Surgical repair in these cases has been excellent.

Factors that affect the survival rate of patients with ruptured abdominal aortic aneurysms.

PURPOSE: There has been much discussion in the literature of factors that affect the mortality rate of patients who undergo repair of ruptured abdominal aortic aneurysms. Some studies have suggested restricting patient selection for repair on the basis of certain preoperative factors including age, increased creatinine level, low hemoglobin level, loss of consciousness, electrocardiographic changes, and preoperative cormorbid medical conditions. A retrospective review of 96 patients who underwent repair of a ruptured abdominal aortic aneurysm was performed to determine whether these factors would necessarily be applicable to all populations. METHODS: A retrospective chart review of all patients who underwent repair of a ruptured abdominal aortic aneurysm was performed over a study period of 20 years. Data was analyzed by both univariate and multivariate analysis. RESULTS: The mean age of the patients was 73 years. The intraoperative mortality rate was 23%. The in-hospital mortality rate was 60.4%, with a 30-day mortality rate of 56.3%. By univariate analysis of various factors associated with the mortality rate, hemoglobin level, creatinine level, lowest preoperative and average intraoperative systolic blood pressure, packed red blood cells transfused, estimated blood loss, intraoperative urine output, and temperature were statistically significant. A history of loss of consciousness was also statistically significant. No preoperative comorbid medical conditions were significant, nor was age. On a multivariate analysis, preoperative factors of loss of consciousness, a lowest preoperative systolic blood pressure less than 90 mm Hg, a hemoglobin level less than 10 g/dl, and a creatinine level greater than 1.5 mg/dl were predictive of death. The effects of the hemoglobin level, creatinine level, and loss of consciousness on the mortality rate were strongest in patients who had a lowest preoperative systolic blood pressure greater than 90 mm Hg. In patients who had the sets of preoperative factors that were associated with a 100% mortality rate, there were intraoprative factors that influenced their death. CONCLUSIONS: These findings suggest that the factors (loss of consciousness, creatinine level, hemoglobin level) that are predictive of death may be a reflection of shock in this patient population. Further studies should be directed to optimizing preoperative resuscitation. Patients who have a ruptured abdominal aortic aneurysm should not be denied therapy on the basis of any specific set of preoperative factors.

Laparoscopic-assisted abdominal aortic aneurysm repair.

Since the advent of laparoscopy, the sweeping changes seen in general surgery have not been paralleled in vascular surgery. There have been case reports of laparoscopic-assisted aortobifemoral bypass for occlusive disease. Because aneurysmal disease comprises the majority of aortic surgery, we pursued animal and cadaveric feasibility studies for laparoscopic-assisted abdominal aortic aneurysm (AAA) repair. We present a case report of the first clinical case performed under Institutional Review Board protocol using this technique. The patient was a 62-year-old male with a 6-cm infrarenal AAA. After obtaining a pneumoperitoneum, a modified fish retractor was used to exclude the bowel. Ten 11-mm ports provided access to laparoscopically dissect the neck of the aneurysm and the iliac vessels. Then, a 10-cm minilaparotomy was performed and standard vascular clamps were inserted via the port incisions. Standard aneurysmorraphy was performed with a polytetrafluoroethylene (PTFE) tube graft. Laparoscopy conferred three major benefits: better visualization of the aneurysm neck, less bowel manipulation, and avoidance of hypothermia. This case report illustrates the feasibility of laparoscopic-assisted aneurysm repair. Controlled human studies will define the role of laparoscopy in AAA surgery.