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Randomized controlled trial of cervical cap with intracervical reservoir versus standard intracervical injection to inseminate cryopreserved donor semen.

A prospective controlled study of donor insemination without sperm preparation or ovarian stimulation was performed to compare the use of a cervical cap incorporating an intracervical reservoir with a standard intracervical injection technique to inseminate 0.5 ml cryopreserved semen. Treatments were alternated in successive cycles in each patient after initial randomized selection. A total of 198 patients had 635 treatment cycles (median 3, range 1-7), 309 with reservoir and 326 by standard injection. A total of 56 women became pregnant, 24 (7.8% per cycle) with the reservoir and 32 (9.8% per cycle) by injection. There were no significant differences between the pregnancy rates per cycle overall or cycle-specific cumulative rates calculated using the life-table method. There were no significant differences in age, parity, baseline gonadotrophin measurements, mid-luteal serum progesterone concentrations, frequency of adverse fertility factors in the woman or her partner's cause of infertility between women who conceived and those who failed to conceive. We conclude that use of a cervical reservoir and cap for donor insemination does not offer any advantage over standard intracervical insemination.

Adult↗

Interim report of a randomized trial comparing Zoladex 3.6 mg depot with diethylstilbestrol 3 mg/day in advanced prostate cancer. The West Midlands Urology Research Group.

A study comparing Zoladex 3.6 mg depot with diethylstilbestrol (DES) 3 mg/day was initiated in August 1985. One hundred ninety-three patients with histologically confirmed prostate cancer T3/4 or M1 have been randomized up to 31 March 1987: 95 to Zoladex, 98 to DES. No patient had received prior systemic therapy. There is no bias in the treatment groups in terms of baseline characteristics. Median follow-up is 11 months, and the response rate at 12 months from randomization (CR + PR) for Zoladex is 70 +/- 9.4% and 50 +/- 10.1% for DES. Median time to best response is 6 months for Zoladex and 12 months for DES (using the Kaplan-Meier life table method). Subjective responses are 56 +/- 10.2% for Zoladex and 44 +/- 10% for DES. Five increases in bone pain were found after the first Zoladex treatment, as well as one increased ureteric obstruction. None required treatment withdrawal. Seventeen patients on DES were withdrawn due to adverse reaction (chi 2 = 4.33, 1df, p less than 0.05). Overall survival at 31 March 1987 is 84% for the Zoladex group and 78% for the DES group. This study has shown that Zoladex is superior to DES in achieving early tumor response in advanced prostate cancer, without causing serious complications warranting withdrawal of treatment.

Buserelin↗

Sodium protects against nephrotoxicity in patients receiving amphotericin B.

Neutropenic patients receiving amphotericin B, frequently in combination with aminoglycosides and vancomycin, were prospectively monitored for the development of nephrotoxicity. Based on previous studies, the authors recommended that these patients receive greater than or equal to 90 meq of sodium/day on each day of amphotericin B administration. Patients who received this amount of sodium on every day of amphotericin B therapy were classified as adequate sodium. The adequate sodium group was further subdivided on the basis of whether or not the adequate sodium was in the form of sodium ticarcillin. Patients not receiving this amount of sodium on every day of amphotericin B therapy were classified as inadequate sodium; overall, these patients received greater than or equal to 90 meq of sodium/day on 74% of days on which they received amphotericin B. The inadequate sodium and adequate sodium groups did not differ significantly with respect to age, gender, diagnoses, or baseline creatinine. The incidence of nephrotoxicity (creatinine greater than or equal to 2.0 mg/dl) was significantly higher, 4 of 14 (29%), in the inadequate sodium group, as compared to the adequate sodium, adequate ticarcillin group, 1 of 35 (3%), or the adequate sodium only group, 1 of 24 (4%), p = .008. To adjust for total amphotericin dose, the risk of nephrotoxicity as a function of time on study was evaluated by the life table method; the risk of nephrotoxicity was significantly greater in the inadequate sodium group, p = .019.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗

Kidney transplantation: Improvement in patient and graft survival.

Patient and graft survival were reviewed in a series of 249 kidney transplants done from 1963 to March 1973. Patient survival was calculated by the life table method for the periods 1963-1970, and 1970-1973, since in 1970 a formal Kidney Center was established and mortality rates changed. Graft survival was analyzed in terms of donor source, HL-A matching and immune responsiveness to HL-A antigens. Three-year predicted mortality for cadaver kidney recipients was 62% between 1963 and 1969 (42 patients) and 8% between 1970 anid 1973 (67 patients). Similar predicted mortality for related living donors was 30% between 1963 and 1969 (52 patients) and 14% between 1970 and 1973 (85 patients). Mortality has continued to decrease and there has been only one death in the last 87 consecutive transplants, including 57 consecutive cadaver transplants. Oneyear predicted kidney survival for the 10-year period is 44% for cadaveric, 60% for non HL-A identical related living and 90% for HL-A identical sibling donors. In the cadaver group, those sharing 2 or more HL-A antigens had the same kidney survival as the non HL-A identical related living donor grafts. Since cadaver graft recipients are on dialysis for a longer period of time, immune responsiveness can be detected by their response to blood transfusions, whereas this determination could not be made in our related living donor group. Non-responsive cadaver kidney recipients had 80% one year kidney survival. We conclude that transplant mortality can be reduced to less than 10% by the Center approach to treatment of renal disease, dialysis does not adversely affect future transplantation, and excellent (80%) kidney survival can be expected in properly selected cadaver graft recipients.

Blood Transfusion↗

A three year experience using modified bovine arterial heterografts for vascular access in patients requiring hemodialysis.

Between January 1974 and December 1976 28 arteriovenous fistulae were created in 25 uremic patients using modified bovine arterial heterografts. Bovine grafts were inserted only if the patient's own vessels were deemed inadequate to permit the development of a useable Brescia fistula. Graft patency by the life-table method was 92% at three months and 75% at one year. Complications leading to graft failure included late thrombosis, inadequate healing of skin flaps, and graft disruption secondary to faulty cannulation. Ten patients died; none of the deaths were graft-related. At the end of the period of observation all patients requiring hemodialysis had functioning bovine grafts. It is felt that for this purpose the modified bovine arterial heterograft is superior to any other currently available vascular conduit. The location of these grafts should be planned so as to make maximal use of distal vasculature and allow multiple sequential access procedures in the same extremity. An idealized approach which encompasses these principles is presented.

Adolescent↗

Infrapopliteal arterial reconstruction in the severely ischemic lower extremity. A comparison of long-term results of peroneal and tibial bypasses.

The feasibility of limb salvage with bypasses to the infrapopliteal arterial tree has been established. In this review, our experience with bypasses to the peroneal artery is compared with that to the tibial arteries. Autogenous saphenous veins were employed in 164 limb salvage arterial revascularizations because of gangrene, ischemic ulceration, or rest pain. These were retrospectively analyzed by the life-table method. Femorotibial (137) or femoroperoneal (27) bypasses were performed on the basis of adequate preoperative arteriograms demonstrating the distal arterial tree, but with no popliteal runoff. Overall operative mortality was 6.1%. Initial limb salvage was 71.2 +/- 3.9% following femorotibial bypass and 51.9 +/- 9.6% after femoroperoneal bypass. Five and seven year cumulative limb salvage rates for femorotibial bypass were 48.5 +/5.2% and 43.4 +/- 6.7%; those for femoroperoneal were equivalent at 38.2 +/- 9.9%. Since long-term limb salvage can be realized in a large number of patients by revascularization of the distal arterial tree, primary amputation is seldom indicated. Operative approach to the ischemic limb must be based on a thorough preoperative arteriogram which demonstrates contrast within vessels down to the distal foot. This is almost always seen and arterial reconstruction is usually feasible. Therefore, limb salvage should be attempted in lieu of primary amputation whether tibial or peroneal arteries are visualized on preoperative arteriogram.

Adult↗

Selective gastric vagotomy and drainage for duodenal ulcer: a 10-13-year follow-up study.

From 1964 to 1968 selective gastric vagotomy (SGV) and drainage was performed in 174 patients. Of these, 105 patients were followed-up 10-13 years after operation; 56 were dead. Ulcers recurred in 18 patients. The cumulated recurrence rate after 13 years (life table method) was 15% (95% confidence limits: 8-23). The method for drainage was usually either a Heineke-Mikulicz or a Finney pyloroplasty. There was a significantly higher risk of ulcer recurrence in the group that underwent Heineke-Mikulicz drainage procedures. The incidence of dumping and diarrhea had not changed during a five-year follow-up period. Two patients were slightly anemic. No patient was iron-deficient. Apart from two recurrent ulcers, gastroscopic examinations in 36 patients revealed no major changes, and biopsy specimens showed slight to moderate chronic atrophic gastritis in most cases. Visick grading showed 77% of the ulcers in Grade I + II, 19% in Grade VI. It is concluded that SGV has no place in the elective treatment of duodenal ulcer. Two alternatives are suggested.

Adult↗

Transduodenal sphincteroplasty. 5-25 year follow-up of 89 patients.

Between 1957 and 1977, 95 patients underwent transduodenal pancreatic sphincteroplasty (TPS) for a diagnosis of recurrent pancreatitis. Five to twenty-five year follow-up was obtained for 89 patients (94%) and was analyzed by life-table method. Short-term successful outcome was defined as relief of symptoms (e.g., pain) for one to three years; long-term successful outcome was defined as those patients who remained symptom-free at time of last follow-up. Operative mortality was 4.2% (4 patients). Fifty-six patients (66%) had a successful short-term outcome. Of these, 13 patients had recurrence of symptoms: 7 occurred at 4 years, 5 at 5 years and 1 at 6 years. Preoperative factors associated with poor short-term outcome were previous upper abdominal surgery (X2 = 5.67, p less than 0.05) and frequent diarrhea (X2 = 6.18, p less than 0.05). Preoperative factors associated with poor long-term outcome were previous upper abdominal surgery (X2 = 7.82, p less than 0.01), heavy alcohol intake (X2 = 4.71, p less than 0.05), narcotic use (X2 = 5.68, p less than 0.05) and frequent diarrhea (X2 = 4.8, p less than 0.05). Morphine Prostigmin Test (MPT) was performed preoperatively in 78 patients (82%). A significantly greater proportion of patients with a rise in serum pancreatic enzymes secondary to MPT (MPT+) had a successful long-term outcome compared with those without such a rise (MPT-) (61% v 41%, X2 = 5.13, p less than 0.05). Furthermore, of the patients with a successful short-term outcome, 88% with MPT+ remained long-term symptom-free compared to 38.5% with MPT- (X2 = 8.36, p less than 0.01). We conclude that TPS can be a successful operation for acute recurrent pancreatitis. Previous upper abdominal operations, signs of more advanced pancreatic disease, preoperative narcotic use and alcohol abuse, were associated with a worse outcome and probably associated with chronic recurrent pancreatitis. Preoperative use of MPT, coupled with accurate clinical history, defined groups with different short- and long-term prognosis after TPS.

Abdomen↗

Seven-year follow-up of expanded polytetrafluoroethylene (PTFE) femoropopliteal bypass grafts.

Expanded polytetrafluoroethylene (PTFE) grafts have proven to be an acceptable short-term alternative for femoropopliteal reconstruction in those patients without suitable autologous saphenous vein. One hundred and twenty-seven femoropopliteal arterial bypass operations utilizing PTFE grafts were performed in 105 patients. Seven-year follow-up is now available for 20 grafts, 6-year follow-up for 47 grafts, and 5-year follow-up for 62 grafts. Graft occlusion was determined by angiography, Doppler assessment, loss of previously palpable pulses, or return of symptoms. Thirty nonocclusive graft losses were due to death, infection, aneurysm, amputation, or proximal occlusive disease. Overall cumulative patency rate, according to occlusive criteria alone and calculated by the life-table method, was 74% at 6 months, 63% at 1 year, 48% at 3 years, 40% at 5 years, and 35% at 7 years. Excluding early bypass failures (less than 1 year patency), 75% of grafts were patent at 3 years, 63% at 5 years, and 55% patent 7 years following operation. Diabetes mellitus was associated with a significantly lower patency rate. Patency rates were not adversely affected by graft diameter, distal popliteal anastomotic site, number of patent runoff vessels, preoperative symptoms, or prior arterial reconstruction. In patients without suitable autologous saphenous vein, the PTFE graft has proven to be a durable and dependable long-term alternative for femoropopliteal reconstruction.

Adult↗

A technique for profunda femoris artery reconstruction. Hemodynamic assessment and functional results.

A modified technique of profunda femoris artery reconstruction is presented. In case of occlusion of the superficial femoral artery, the proximal segment of this vessel is rolled over the profunda femoris artery as a patch after an endarterectomy has been performed. This technique has been performed in 110 patients (131 limbs) during the last 14 years. Five-year actuarial patency rate (life-table method) was 65.3%. With measurements obtained from nine biplanar angiograms, glass models of three different methods of profunda femoris reconstruction were constructed. The model representing this modified technique of profundaplasty showed less turbulence than the others. The results of this study validate the use of this type of profundaplasty in clinical practice.

Actuarial Analysis↗

The Kaplan and Meier and the Nelson estimate for the probability of ulcer recurrence 10 and 15 years after parietal cell vagotomy.

The use of a nonparametric estimate from incomplete observations is demonstrated on ulcer recurrence 10-15 years after parietal cell vagotomy in 339 patients with duodenal ulcer. The median period of observation was 108 months (range: 1-197 months). Proven recurrent ulcer developed in 62 patients. The life-table method as described by Kaplan and Meier and Nelson's modification are demonstrated. The calculated risk of recurrence after 10 years was 23% (+/- 3.8%) and after 15 years was 27% (+/- 4.3%). The rate of recurrence seemed to decline toward the end of the trial time.

Duodenal Ulcer↗

Prospective controlled vagotomy trial for duodenal ulcer. Results after 11-15 years.

A prospective, randomized, controlled trial was conducted to compare truncal vagotomy and drainage (TV), selective vagotomy and drainage (SV) and parietal cell vagotomy (PCV) as elective treatment for duodenal ulcer. Between 11 and 15 years after operation, 248 patients were available for study of the recurrent ulceration rate by a life table method, and 197 patients could be studied with regard to postvagotomy symptoms. The recurrent ulcer rates were 28.5% for TV, 37.4% for SV, and 39.3% for PCV. These differences were not statistically significant. The incidence of severe postvagotomy symptoms was as follows: dyspepsia, 18.4% for TV, 20.5% for SV, 8.6% for PCV; dumping, 5.9% for TV, 19.6% for SV, 2.2% for PCV; diarrhea, 9.8% for TV, 11.8% for SV, 4.4% for PCV. The incidence of severe dumping was significantly less frequent among the PCV patients than the SV group. The differences did not reach statistical significance in any of the other groups. There was no significant difference in the Visick gradings among the three groups either before or after treatment of the failures. About two thirds of the patients in each group were finally satisfied with their operation, often after second operations or prolonged medical treatment. It is concluded that none of the three forms of vagotomy can be recommended as the standard operative treatment of duodenal ulceration.

Clinical Trials as Topic↗

Factors associated with morbidity and mortality among patients on CAPD.

Since 1981, the National CAPD Registry, sponsored by the National Institute of Arthritis, Diabetes, Digestive, and Kidney Diseases of the National Institutes of Health, has been systematically collecting demographic and follow-up data on patients receiving continuous ambulatory peritoneal dialysis (CAPD) as maintenance therapy for end-stage renal disease. Using life-table methods, this study has identified the association of diabetic glomerulosclerosis with age over 60 or under 20 years as factors jointly relevant in predicting peritonitis, hospitalization, or death. In addition, these outcomes were more likely to occur if patients were black and had been exposed to other dialytic therapy earlier on. The latter two were the only factors jointly predictive of transfer from CAPD onto hemodialysis. Careful monitoring of patients with the above mentioned characteristics may reduce complications, and lead to greater success with this increasingly popular dialysis modality.

Adult↗

Rehospitalization in chronic schizophrenia.

This report on rehospitalization in chronic schizophrenia is based on a 1-year study of the postdischarge experiences of 119 chronic schizophrenics in New York City. The life table method of analysis identified the important role of discharge planning, community treatment compliance, and interpersonal stress in the patient's living environment in determining the number of days postdischarge that the patient remained in the community without further inpatient care. A mathematical model to predict days in hospital over the follow-up period, based on three specific components of time in hospital defined in numerical terms (PR, NR, LSR), was devised and tested. The first component, the experience of rehospitalization (PR), was determined by interpersonal stress, social supports, and aftercare treatment compliance. Adequacy of discharge planning, an intervention designed to link the patient to community treatment services, has its greatest impact in identifying number of rehospitalizations for the rehospitalized group (NR). Aftercare treatment compliance has its greatest effect in relation to length of subsequent rehospitalization episodes (LSR). Test of the model revealed that it can predict time in hospital within less than one half of a standard deviation of observed hospital days in approximately 50% of cases.

Actuarial Analysis↗

The length-of-stay pattern of nursing home admissions.

The length of stay (LOS) pattern of nursing home admissions has not been directly measured because the long duration of stay of some patients (e.g., 25% of persons admitted reside in homes for longer than 1 year) makes it impractical to follow specific admission cohorts until the members have been discharged. By applying life-table methods to data on current and discharged residents from the 1977 National Nursing Home Survey, the authors were able to generate estimates of this distribution. They estimated that the typical nursing home admission initially has an expected LOS of 456 days, but, more interesting, the remaining LOS is expected to increase, in the intermediate term, with the amount of time spent in the facility. They also examined LOS distributions of subsets of the national nursing home population, and illustrated potential applications for this new information for policy formulation.

Actuarial Analysis↗

Experimental microvascular polytetrafluoroethylene grafts: 6-month patency.

The efficacy of 1-mm internal-diameter polytetrafluoroethylene as a microvascular prosthesis is unclear. In this study, 8-mm-long segments of this material were implanted into the femoral arteries of 30 rats. Animals were examined every 2 weeks up to 6 months by Doppler ultrasound. Cumulative patency by the life-table method was 86.7 percent at 6 months. There were 26 patent grafts, 2 occlusions, and 2 deaths. Intimal hyperplasia adjacent to the anastomoses was seen in the native arteries. The pseudointima lining the grafts was cellular near the anastomoses but usually acellular in midgraft regions. It is concluded that if early failure does not occur, then good long-term patency is possible with 1-mm polytetrafluoroethylene in this setting and that patency is not dependent on development of a cellular pseudointima. Longer graft segments should be evaluated in future studies.

Actuarial Analysis↗

Evidence that zero antigen-matched cyclosporine-treated renal transplant recipients have graft survival equal to that of matched recipients. Reevaluation of points.

The value of HLA matching in cadaver renal transplantation (CRT) continues to be debated. It has recently been suggested that increased importance be given to HLA matching for the distribution of cadaver kidneys. Such a policy would add both delay and expense to CRT, which could be justified only by significantly improved results. The results of CRT in 252 cyclosporine treated adult patients transplanted at our institution from November 1984 to April 1989 were reviewed. Kidneys were initially transplanted into crossmatch-negative recipients based on waiting time, regardless of match. From October 1987, a points system, based on United Network for Organ Sharing (UNOS) criteria has been used. Eighty-four pts. with zero antigen match with their donors were compared with 168 pts. sharing 1-6 Ag. Actuarial graft and patient survival were determined by the cumulative life table method and compared using a log rank test. Our results indicated no statistically significant difference in graft survival because of better matching or mismatching. These findings are in keeping with our previously reported long-term results for non-CsA pts. Past predictions of improved graft survival based upon better matching at our institution have not fulfilled expectations, with the exception of 6 Ag matches. In conclusion, increased emphasis on HLA matching with fewer "points" for poorer matches does not appear justifiable.

Adult↗

Probability of early repeat Pap smear in an integrated cervical screening programme.

The integration of routine Pap smear practice based on self-referral into an organized programme based on personal invitation is the recommended approach to cervical cancer screening. In this study, the cytology archive of the integrated cervical screening programme implemented in the Faenza district (northern Italy) was used to compare the population of women responding to invitation with that of self-referred women for the cumulative probability of early (< 36 months) repeat Pap smear after a negative result. Between 1995 and 1998, women aged 25-64 living in five municipalities of the district were targeted by the first round of the programme. Eligible for the study were 2356 women responding to invitation for screening and 2221 women not invited because of self-referral for Pap smear at any other setting. The probability of early repeat Pap smear was estimated by the life table method. Differences were evaluated by the Gehan test. Multivariate determinants were assessed by the Cox regression analysis. At 36 months' follow-up, the cumulative probability of early repeat Pap smear was 44% among self-referred women and 6% among women responding to invitation (relative hazard = 4.8). For self-referred women, the probability was related to age (with a peak at 35-44 years), previous Pap smear history and municipality of residence. Among women responding to invitation, only an inverse association with age was demonstrated. In conclusion, the observed differences in overall probability and determinants of early repeat Pap smear between the two screening populations provided important information on Pap smear usage in the total target population.

Adult↗