A multivariable model for predicting the need for blood transfusion in patients undergoing first-time elective coronary bypass graft surgery.

BACKGROUND: The incidence of blood transfusion in coronary artery bypass graft (CABG) surgery remains high. Preoperative identification of those at high risk for requiring blood will allow for the cost-effective use of some blood conservation modalities. Multivariable analysis techniques were used in this study to develop a prediction rule for such a purpose. STUDY DESIGN AND METHODS: Data were prospectively collected for all patients undergoing elective first-time CABG surgery from January 1997 to September 1998 at a tertiary-care teaching hospital (n = 1007). The prediction rule was developed on the first two-thirds of the sample by using logistic regression methods to examine the relationship of patient demographics, comorbidities, and preoperative Hb with perioperative blood transfusion. The remaining one-third of the sample was used to validate the rule. RESULTS: The transfusion rate was 29.4 percent. The prediction rule included preoperative Hb (g/dL, OR 0.928, p<0.0001), weight (kg, OR 0.938, p<0.0001), age (years, OR 1.037, p<0.01), and sex (male/female, OR 0.493, p<0.01); receiver operating characteristic = 0.86. When externally validated, the rule had a sensitivity of 82.1 percent and a specificity of 63.6 percent (at a selected probability cutoff). CONCLUSION: A simple and valid prediction rule is developed for predicting the risk of blood transfusion in patients undergoing first-time elective CABG surgery.

Effect of premedication guidelines and leukoreduction on the rate of febrile nonhaemolytic platelet transfusion reactions.

Platelet transfusion reactions were prospectively studied in haematology/oncology patients at five university teaching hospitals over three consecutive summers. The initial summer study provided baseline information on the use of premedications and the rate of platelet transfusion reactions (fever, chills, rigors and hives). Most (73%) platelet recipients were premedicated and 30% (95% CI 28-33%) of transfusions were complicated by reactions. The second study followed implementation of guidelines for premedicating platelet transfusions. Despite a marked reduction in premedication (50%), there was little change in the platelet transfusion reaction rate, 26% (95% CI 24-29%), or the type of reactions. The third study followed implementation of prestorage platelet leukoreduction while maintaining the premedication guidelines. The reaction rate decreased to 19% (95% CI 17-22%). For nonleukoreduced platelets, there was a statistically significant association between the platelet age and reaction rate (P = 0.04). For leukoreduced platelets, there was no statistically significant association between platelet age and reaction rate (P = 0.5). Plasma reduction of nonleukoreduced platelet products also reduced the reaction rate. These prospective studies document a high rate of platelet transfusion reactions in haematology/oncology patients and indicate premedication use can be reduced without increasing the reaction rate. Prestorage leukoreduction and/or plasma reduction of platelet products reduces but does not eliminate febrile nonhemolytic platelet transfusion reactions.

Allogeneic red blood cell transfusion is an independent risk factor for the development of postoperative bacterial infection.

BACKGROUND AND OBJECTIVES: Allogeneic red blood cell transfusions may exert immunomodulatory effects in recipients including an increased rate of postoperative bacterial infection. It is controversial whether allogeneic transfusion is an independent predictor for the development of postoperative bacterial infection. METHODS: We analysed a prospectively collected database of 1,349 patients undergoing colorectal surgery in 11 centres across Canada. The primary outcome was the development of either a postoperative wound infection or intra-abdominal sepsis in transfused and nontransfused patients. The effect of allogeneic transfusion on postoperative infection was evaluated with adjustment for all the confounding factors in a multiple regression analysis. RESULTS: The 282 patients who received a total of 832 allogeneic units had a significantly higher frequency of wound infections and intra-abdominal sepsis than the patients who were not transfused (25. 9 vs. 14.2%, p = 0.001). A significant dose-response relationship between transfusion and infection rate was demonstrated. Multiple regression analysis identified allogeneic transfusion as a statistically significant independent predictor for postoperative bacterial infection (OR 1.18, 95% CI 1.05-1.33, p = 0.007). Other independent predictors were anastomotic leak, repeat operation, patient age and preoperative haemoglobin level. The mortality rate was also significantly higher in the transfused group. CONCLUSION: These data support the hypothesis that allogeneic red cell transfusion is an independent risk factor for the development of postoperative bacterial infection in patients undergoing colorectal surgery. This association provides further reason to minimise exposure to allogeneic transfusions in the perioperative setting.

Vaginal sildenafil (Viagra): a preliminary report of a novel method to improve uterine artery blood flow and endometrial development in patients undergoing IVF.

Endometrial growth is thought to depend on uterine artery blood flow and the importance of endometrial development on in-vitro fertilization (IVF) outcome has been previously reported. Nitric oxide (NO) relaxes vascular smooth muscle through a cGMP-mediated pathway and NO synthase isoforms have been identified in the uterus. Sildenafil citrate (Viagra), a type 5-specific phosphodiesterase inhibitor, augments the vasodilatory effects of NO by preventing the degradation of cGMP. In this preliminary report we describe the use of vaginal sildenafil to improve uterine artery blood flow and sonographic endometrial appearance in four patients with prior failed assisted reproductive cycles due to poor endometrial response. The uterine artery pulsatility index (PI) was measured in a mock cycle after pituitary down-regulation with Lupron. The PI was decreased after 7 days of sildenafil (indicating increased blood flow) and returned to baseline following treatment with placebo. The combination of sildenafil and oestradiol valerate improved blood flow and endometrial thickness in all patients. These findings were reproduced in an ensuing gonadotrophin-stimulated cycle. Three of the four patients conceived. Although greater numbers of patients and randomized evaluation are needed to validate this treatment, vaginal sildenafil may be effective for improving uterine artery blood flow and endometrial development in IVF patients with prior poor endometrial response.

Prevalence of GBV-C/hepatitis G virus viremia and anti-E2 in Canadian blood donors.

BACKGROUND AND OBJECTIVES: GB virus C (GBV-C)/hepatitis G virus (HGV) is a recently recognized parenterally and sexually transmitted agent. The prevalence of GBV-C/HGV markers in Canadian blood donors has not been previously studied and was therefore determined. MATERIALS AND METHODS: Blood donors [identity unlinked (IU), short-term temporarily deferred (STTD) and autologous groups] and donor samples with antibodies to hepatitis C (anti-HCV) or hepatitis B core were tested for GBV-C/HGV RNA and for antibodies to E2 antigen (anti-E2). RESULTS: GBV-C/HGV RNA was found in 1.1% and anti-E2 in 7.3% of the combined IU/STTD donor group. Viremia was much more common in anti-HCV-positive samples (12.5%); anti-E2 was present in >50% of this group. In the STTD group, female gender was significantly associated with viremia. CONCLUSION: GBV-C/HGV infection is relatively common in Canadian donors, and a small proportion are viremic. The association of female gender and viremia was unexpected. Further study is needed to clarify the epidemiology and natural history of GBV-C/HGV infection.

Prospective audit of cytomegalovirus-negative blood product utilization in haematology/oncology patients.

The transfusion management of immunocompromised patients often requires special blood product use such as cytomegalovirus (CMV)-negative cellular products, which are more costly than standard blood products and occasionally in short supply. We audited the use of CMV-negative products in haematology/oncology patients to determine the appropriateness of their use. A concurrent-prospective audit was conducted of all orders for CMV-negative packed red blood cell (PRBC) and platelet products in 201 haematology/ oncology patients. Once CMV serostatus was determined, orders for inappropriate CMV-negative units were cancelled, and filled as CMV untested units. During the 21-month period of this audit, the rates of inappropriate transfusions decreased for PRBC from 73.2% to 14.3% (chi2 = 68.4, P<0.001) and for platelets from 68.1% to 10.6% (chi2 = 65.6, P<0.001). The median time to cancellation of inappropriate CMV-negative orders was 11 days. This audit resulted in estimated cost savings of $16500 over the 21-month duration. Inappropriate requests for scarce and expensive blood products are substantially reduced by concurrent-prospective auditing of transfusion practice, in a manner that is both simple and cost effective.

'Prolonged coasting': an effective method for preventing severe ovarian hyperstimulation syndrome in patients undergoing in-vitro fertilization.

Over a 4 year period ending 1 January 1995, 51 women scheduled for in-vitro fertilization (IVF) and embryo transfer were inadvertently severely overstimulated with menotrophins, as evidenced by the development of > 29 ovarian follicles in association with peak plasma oestradiol concentrations of > 6000 pg/ml. Accordingly, these women were at great risk of developing life-endangering complications associated with severe ovarian hyperstimulation syndrome (OHSS). Treatment involved withholding the administration of both menotrophins and human chorionic gonadotrophin for a number of days, while continuing gonadotrophin-releasing hormone agonist until the plasma oestradiol concentration fell to < 3000 pg/ml ('prolonged coasting'). The mean number of oocytes retrieved was 21.0, while the mean number of embryos transferred per procedure was 5.4. There were 21 clinical pregnancies (i.e. pregnancy rate of 41% per oocyte retrieval), 19 of which resulted in live births (i.e. a live birth rate of 37% per oocyte retrieval). Two pregnancies miscarried and there were four multiple gestations (three sets of twins and one set of triplets). None of the women developed severe OHSS. Prolonged coasting is an effective method of preventing the occurrence of severe OHSS without necessitating the cancellation of the IVF cycle or compromising success rates.

Engraftment of immune-deficient mice with primitive hematopoietic cells from beta-thalassemia and sickle cell anemia patients: implications for evaluating human gene therapy protocols.

Permanent correction of genetic deficiencies of the hematopoietic system requires gene transfer into stem cells and long-term lineage specific expression after autologous transplantation. However, progress to develop gene therapy protocols has been hampered by the absence of in vivo assays that detect genetically deficient human hematopoietic stem cells and their diseased differentiated progeny. The establishment of systems to transplant human cells into immune-deficient SCID mice provides such an assay. We report that primitive bone marrow cells from beta-thalassemia major and sickle cell anemia patients engraft immune-deficient mice, giving rise to high levels of human erythroid and myeloid cells in response to treatment with human cytokines. The bone marrow of transplanted mice contained the entire erythroid lineage from BFU-E to mature erythrocytes expressing human gamma, beta or beta s-globin. Moreover, human erythroid cells from mice transplanted with sickle cell anemia bone marrow showed characteristic sickling under reducing conditions in an in vitro assay. This model provides a powerful in vivo system that can be used to evaluate the efficiency of globin gene transfer into primitive human hematopoietic cells, lineage-specific expression in mature erythrocytes, and ultimately correction of the cellular defect found in the erythroid lineage.

Myelodysplastic syndrome with prolonged reticulocyte survival mimicking hemolytic disease.

A patient with myelodysplastic syndrome (refractory anemia) with marked and persistent reticulocytosis is presented. A referring diagnosis of hemolytic disease had been made. However, the 51Cr red cell survival was normal (T1/2 24 days). Reticulocyte morphology, red cell creatine content, and in vitro reticulocyte survival studies have suggested that the reticulocytosis arose as a consequence of delayed maturation of the reticulocytes. Two patients with myelodysplastic syndrome and delayed reticulocyte maturation have previously been described; in both patients, however, red cell survival was also shortened. Anemia with reticulocytosis, mimicking hemolytic disease, may be an unusual presentation of myelodysplastic syndrome.

High fecundity rates in donor oocyte recipients and in-vitro fertilization surrogates using parenteral oestradiol valerate.

Ovum donation and in-vitro fertilization (IVF) surrogacy can help couples with difficult infertility problems achieve pregnancy. Most centres using oral oestrogens and oestradiol patches report pregnancy rates in the range of 30% per cycle. Parenteral oestradiol valerate has pharmacological properties that make it an attractive option for preparing the endometrium in the recipients undergoing these procedures. When the egg providers were under age 35 years, and using oestradiol valerate in the recipients, we achieved a 61% clinical pregnancy rate in 62 cycles. These improved results suggest that parenteral oestradiol valerate should be used to prepare the endometrium in recipients, and that the hormonal milieu of the endometrium plays an important role in the higher implantation rates obtainable in ovum donor and IVF surrogate cycles.

Eliminating the risk of life-endangering complications following overstimulation with menotropin fertility agents: a report on women undergoing in vitro fertilization and embryo transfer.

OBJECTIVE: To evaluate a new method for preventing the life-endangering complications associated with inadvertent menotropin-induced severe ovarian hyperstimulation in patients undergoing in vitro fertilization and embryo transfer (IVF-ET). METHODS: Seventeen women each underwent a single cycle of controlled ovarian hyperstimulation with menotropins in preparation for IVF-ET. The indications for IVF-ET were tubal occlusion in nine, endometriosis in six, and unexplained infertility in two. The peak plasma estradiol (E2) concentration before hCG administration was greater than 6000 pg/mL and more than 30 ovarian follicles were detected by transvaginal ultrasound. Thus, life-endangering complications associated with severe ovarian hyperstimulation syndrome were highly likely to occur following hCG administration. Rather than cancel the cycle of treatment, menotropin therapy was discontinued and hCG administration was deferred for a number of days until the plasma E2 concentration fell below 3000 pg/mL ("prolonged coasting"), whereupon hCG was administered and egg retrievals and ETs were duly performed. RESULTS: None of the women developed severe ovarian hyperstimulation syndrome. There were six viable pregnancies (35.2%), which proceeded normally. CONCLUSION: This study indicates that "prolonged coasting" prevents severe ovarian hyperstimulation syndrome in severely overstimulated women undergoing IVF-ET, without necessitating cycle cancellation.

Management of suboptimal sonographic endometrial patterns in patients undergoing in-vitro fertilization and embryo transfer.

A total of 816 women who underwent 1332 cycles of ovarian stimulation for in-vitro fertilization and embryo transfer (IVF/ET) had sonographic assessments of the endometrium within 2 days of oocyte retrieval. Endometrial linings were classified on the basis of thickness and echogenicity, using a grading system described previously. Grades I and IIB ('poor') were associated with a 6% viable pregnancy rate (advanced beyond 12 weeks' gestation) compared with a 29% rate for Grade IIA ('optimal'). In a subset of 112 women with poor endometrial linings during natural cycles, eight out of 21 women (38%) under 40 years of age developed optimal linings following ovarian stimulation with menotrophins, while 19 out of 91 women (21%) aged 41-45 years converted to optimal linings. Twenty-two out of 47 women (44%) who failed to develop optimal endometrial linings following ovarian stimulation converted to Grade IIA during subsequent cycles of exogenous oestrogen replacement. The financial, emotional, and physical burden associated with IVF/ET demands that patients with poor endometrial linings following ovarian stimulation with menotrophins be counselled with regard to either cancelling their cycles of treatment, or having their embryos cryopreserved for transfer to the uterus during a subsequent hormonal replacement cycle.

Microinjection of lidocaine into human thalamus: a useful tool in stereotactic surgery.

A new method was developed to aid in the localization of the optimal site for a permanent lesion in movement disorder patients undergoing stereotactic thalamotomy. The method involved making small injections of a local anesthetic into the thalamus, which was also useful in assessing any possible side effects that could potentially arise from the lesion. Initial results indicate that 0.5 to 2-microliters injections of 2% lidocaine at appropriate sites in the thalamic ventrocaudal or ventrointermedius nucleus can produce a temporary marked suppression of tremor. In most cases the lidocaine induced effects mimicked those produced by high frequency electrical stimulation delivered to the same site. However, lidocaine had no effect at some sites where stimulation arrested tremor. This technique promises to be useful not only in the treatment of motor disorder patients but also in other cases where functional localization prior to lesioning is desirable.

Deletion of the long arm of chromosome 5 in essential thrombocythemia.

A 51-year-old woman with no history of prior chemotherapy or radiation therapy was diagnosed with essential thrombocythemia (ET) according to the diagnostic criteria established by the Polycythemia Vera Study Group (PVSG). Cytogenetic analysis of bone marrow metaphases revealed both normal female karyotype and a single clonal abnormality, 46,XX,del(5)(q22q35). While chromosomal abnormalities have been reported in ET, their incidence is very low, and no specific abnormality has been found. Many of the reported cases of ET with chromosomal aberrations, including 5q-, do not meet the diagnostic criteria proposed by the PVSG, and may represent one of the other myeloproliferative disorders or a myelodysplastic syndrome. Furthermore, it is important to distinguish the 5q- syndrome, which may present with thrombocytosis and megakaryocytic hyperplasia, from ET. Our patient appears to be the first example of untreated ET clearly meeting the PVSG criteria in which 5q- was the only clonal abnormality seen at diagnosis.

Assessment of the late proliferative phase endometrium by ultrasonography in patients undergoing in-vitro fertilization and embryo transfer (IVF/ET).

This study reports on 330 women aged 29 to 45 years, who underwent 411 cycles of in-vitro fertilization and embryo transfer (IVF/ET). Vaginal sonograms were performed during the late proliferative phase of natural cycles and cycles of controlled ovarian hyperstimulation (COH) with gonadotrophins, to evaluate both the thickness and echogenicity of the endometrium. Findings classified as Grade I; characterized by homogeneous echogenicity of the endometrium, and Grade II; characterized by an outer peripheral layer of dense echogenicity surrounding a central sonolucent area (i.e. a 'halo pattern'). Grades I and II were subclassified on the basis of thickness into A (greater than or equal to 9 mm) and B (less than 9 mm). Grade IIA ('optimal') was associated with a clinical pregnancy rate per embryo transfer of 33% while Grades IA, IB and IIB ('poor') were associated with a rate of only 7%. Women aged 41-45 years experienced a 25% incidence of 'poor' sonographic grades while the incidence in women less than or equal to 40 years of age was 5%. The presence of various uterine pathologies was associated with 'poor' endometrial grades in 86% of cases while only 11% of normal uteri manifested 'poor' grades. 'Optimal' endometrial grades in natural cycles were consistently associated with 'optimal' grades in ensuing cycles of COH (96%). Women with 'poor' endometrial grades in natural cycles improved in 55% of cases during subsequent COH. The results of this study indicate that sonographic assessment of the endometrial lining in the late proliferative phase during both natural and COH cycles is a valuable method for screening and managing IVF/ET candidates.

In vitro fertilization and embryo transfer: two-year experience.

Between February 1983 and January 1985, 206 laparoscopies were performed on 172 women following controlled ovarian hyperstimulation with human menopausal gonadotropin (hMG) and human chorionic gonadotropin (hCG). Sixty-four clinical pregnancies advanced beyond the sixth week of gestation and were confirmed by ultrasound; and 37.2% of the patients conceived after in vitro fertilization and embryo transfer. The clinical pregnancy rate was 31.1% when based on the number of laparoscopies performed and 33.9% when based on the number of embryo transfers. There were 12 multiple pregnancies (18.8%), 11 miscarriages (17.2%), and one ectopic (tubal) pregnancy (1.6%). The most important factors contributing toward the success of this program were the establishment of specific criteria for patient selection, rigid adherence to clinical and laboratory protocols, and the maintenance of strict quality control.

The development of a successful non-university-based ambulatory in vitro fertilization/embryo transfer program: phase I.

Most of the current in vitro fertilization and embryo transfer (IVF-ET) programs are university-based. The establishment of a successful ambulatory IVF program in association with a busy, two-man general obstetrics-gynecologic practice is described. Seventy-one infertile couples were screened between February 1 and October 15, 1983. Forty-three couples were judged eligible for IVF-ET. Forty-three women underwent a single attempt at ET. The first 13 of these women underwent controlled ovarian hyperstimulation (COH) with 150 mg clomiphene citrate and human chorionic gonadotropin (hCG), and the remaining 30 underwent COH with human menopausal gonadotropin (hMG) and hCG. One of the 13 patients who underwent COH with clomiphene citrate conceived but subsequently miscarried early in the first trimester, for an 8% pregnancy rate. There were 12 pregnancies among the 30 patients who received hMG and hCG, for a 40% pregnancy rate. Only three of these pregnancies miscarried in the early first trimester, and three of the nine viable pregnancies are twin gestations. The possible factors responsible for the high pregnancy rate with IVF-ET, using COH with hMG and hCG, are discussed, and the feasibility of its performance in a well-controlled, non-university program is demonstrated.

Induction of labor following intrauterine death with intra-amniotic hyperosmolar urea and prostaglandin F2alpha: evaluation of placental endocrine function and changes in coagulation parameters.

A practicable and reliable method for inducing labor in patients whose pregnancies are complicated by intrauterine death of the fetus is described. The method involves the intra-amniotic instillation of 30 mg of prostaglandin F2alpha with 60 gm of urea. Twenty patients had pregnancies ranging between 22 and 41 weeks and the estimated duration of fetal death ranged between two and eight weeks. Delivery was achieved within 24 hours in all cases. Side effects and complications were minimal. Plasma human placental lactogen (hPL) and progesterone concentrations, as well as several blood coagulation parameters (i.e., plasma fibrinogen, blood platelet count, and serum fibrin degradation products (FDP) concentrations), were measured immediately prior to induction of labor. The latter (i.e., coagulation factors) were repeated at parturition. The presence of residual viable placenta prior to induction did not influence the induction-delivery interval. No statistically significant alterations in blood coagulation parameters that could be attributed to the specific method of induction employed were noted.

PIP: A practicable and reliable method for inducing labor in patients whose pregnancies are complicated by intrauterine death of the fetus is described. The method involves the intraamniotic instillation of 30 mg of prostaglandin F2alpha with 60 gm of urea. 20 patients were investigated with pregnancies ranging between 22 and 41 weeks and with the estimated duration of fetal death ranging between 2 and 8 weeks. In all cases, delivery was achieved within 24 hours. Prior to the induction of labor, plasma human placental lactogen (hPL); progesterone concentrations; and numerous blood coagulation parameters i.e., plasma fibrinogen, blood platelet count, and serum fibrin degradation products [FDP] concentrations) were measured. No statistically or clinically significant alterations occurred in the first 2 measurements, and FDP concentrations increased during labor in most patients. Side effects and complications were minimal and the induction-delivery interval was not influenced by the presence of residual viable placenta prior to induction. Thus, this method which only requires a single intraamniotic instillation is highly recommended.