Autologous Blood Donations for Hysterectomy

sure measurements in this group of patients, documented normal physiologic variation of blood pressure and changes associated with hypertensive disorders in pregnancy. Interestingly, the chronic hypertensive patients who did not develop superimposed preeclampsia continued to show similar diurnal variations to those seen in controls. However, the chronic hypertensive patients were, as is clinically known, at increased risk for intrauterine growth restriction. From a clinical perspective, the blunting of the nocturnal blood pressure decrease found in severe pregnancy-induced hypertension and preeclampsia may be the result of a loss of the physiologic mechanisms that mediate this rhythm. The authors summarize, and underline our clinical awareness of the fact, that a constant blood pressure increase is mote likely to induce vessel damage, especially renal, and result in greater long-term maternal complications, whereas more acute blood pressure increases are mote likely to cause severe, acute complications such as abruptio placentae, cerebral hemorrhage, cardiovascular failure, and pulmonary edema.

Trimester Weight Gain as a Predictor of Low Birth Weight Hickey CA, Cliver SP, McNeal SF, Hoffman HJ, Goldenberg RL. Prenatal weight gain patterns and birth weight among nonobese black and white women. Obstet GynecoI1996;88:490-6.

Synopsis: Four hundred fifteen nonobese (body mass index [BMI] <26) women were evaluated. Of the women evaluated 275 were black, and 140 were white. Patients were either para 1 or para 2. The weight gain of these women in each trimester was compared with the Institute ofMedicine guidelines. Linear regression analysis was used to examine the impact of low, first-trimester gains «2.3 kg with low BMI [<19.8] and < 1.6 kg with normal BMI [19.8-26.0]) and low second- and third-trimester gains «0.38 kgl week with low BMI and <0.37 kgl

week with normal BMI) on mean birth weight. Members of the black population were rwice as likely to have had an infant weighing <2750 g. The white population had a double risk (77.9%) of currently using cigarettes. Low weight gain during the first or only the second trimester was not associated with a statistically significant reduction at birth weight. Low weight gain during only the third trimester was associated with a significant reduction in birth weight among all women combined and among white women but not among blackwomen. The largest reduction of birth weight occurred in combination with low weight gain in the second trimester and in either the first or third trimester. The authors propose that these observations support the importance of periodically monitoring prenatal weight in nonobese women and of using low weight gain during the second trimester as a potential noncausal marker of risk for fetal low birth weight.

• • • Commentary: The authors' evaluation provides interesting data that indicate an association in the white population berween low birth weight and low maternal weight gain during the second trimester only or during the second and the first or the third trimester. A potential compounding variable here is the use of cigarette smoking in the white population in the study. It is pointed out carefully that obese patients and nulliparous patients have been excluded to eliminate variables by decreased weight gain in the former and potential increase in the latter. The largest reduction in mean birth weight occurred regardless of ethnic group when low ratesofweight gain were present in all three trimesters. This study shows how poor maternal weight gain can be used as a predictor of low birth weight; however, the number of patients in this study is small, and further studies with expanded numbers of patients would be of benefit to confirm these findings. PII 11085·6862(96100046.5

SPOtlIGHT ON

.·GYNECOlOGY

Hal C. Lawrence, III, MD Guest Editor

From the Mountain Area Health Education Center, Department of Obstetrics and Gynecology, Asheville, NC

Autologous Blood Donations for Hysterectomy Kanter MH, van Maanen MT, Anders KH, Castro F, Mya WW, Clark K. Preoperative autologous blood donations before elective hysterectomy. JAMA 1996;276:798 - 801.

Synopsis: This retrospective cohort study evaluated 263 consecutive patients admitted for elective abdominal or vaginal hysterectomy at a community hospital. Twenty-six patients received blood transfusion following their hysterectomies. Twenty-five transfusions were performed in patients who had donated autologous blood, whereas only one transfusion was performed in the group of 123 patients who had chosen not to donate. This difference was significant at P< .001. Patients who chose autologous blood donation had an admission hemoglobin level that was lower than that of patients who chose not to donate, 119 giL versus 132 giL, respectively (P < .05). Patients were compared by age, weight, route of surgery, and preoperative diagnosis. Intraoperative red-cell loss was calculated using a mathematical model. Only preoperative autologous blood donation was found to be statistically significant as an independent variable (P < .001). Recognizing that preoperative autologous blood donation decreases the risk of transfusion acquired AIDS or hepatitis, the authors raised concerns that these individuals may be at higher risk for other adverse events. Iatrogenic anemia as well as the risk of administration of the wrong unit of blood causing a hemolytic reaction volume overloador potential bacterialcontamination wereidentified.The authors reported that the riskofpreoperativeau-

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tologous blood donation for routine hysterectomy in the nonanemic patient may outweigh potential benefits.

• • • Commentary: The appropriate concern regarding transfusion-related illnesses, AIDS or hepatitis, stimulated the use of autologous blood donation prior to elective surgery in the patients studied. Although such donations may be appropriate in situations (eg, placenta previa) in which excessive blood loss and need for transfusion are anticipated, whether preoperative donations are of benefit for routine hysterectomy is debatable. When patients with preexisting anemia are excluded, the incidence of transfusion in an uncomplicated population is quite low-the authors reported a rate of 0.8%. Physicians sometimes transfuse the autologous donor postoperatively, regardless of whether or not the patient has met the clinical indications for a transfusion. This practice potentially increases risk and definitely increases costs.

Hormone

Re~lacemenl Therapy &Cardiovascular Disease Grodstein F, Srampfer MJ, Manson JE, Colditz GA, Willett WC, Rosner B, et aI. Postmenopausal estrogen and progestin use and the risk of cardiovascular disease. N Engl

J Med 1996;335:453-61.

Synopsis: This follow-up report from the Nurses' Health Study evaluated women age 30-55 for the effects of hormone replacement therapy on the occurrence of myocardial infarction or death from coronary disease and cerebral vascular accidents. From 1976 to 1992, 770 cases of myocardial infarction or death and 572 strokes were identified. A marked decrease in the risk of major coronary heart disease among women who took estrogen and progesterone, as compared with risk among women who did not use hormones, was identified (multivariate adjusted relative risk, 0.39; 95% confidence interval, 0.19,

0.78). The estrogen-alone population relative risk was 0.60 (95% confidence interval, 0.43, 0.83). No significant association between stroke and the use of combined hormones or estrogen alone was identified. There was a trend toward an increased risk of stroke with higher doses (>0.625 mg) of estrogen. Hormone-related protection against coronary artery disease appears to diminish somewhat :2':3 years following cessation of therapy. The relative risk of coronary artery disease in women who had ceased to use hormone replacement therapy for <3 years was 0.69, whereas 3-4.9 years after cessation, the relative risk was 0.81. The authors concluded that the addition of progestin does not appear to attenuate the cardioprotective effects of postmenopausal estrogen therapy.

• • • Commentary: This study further substantiates the cardioprotective effect of estrogen or estrogen plus progestin hormone replacement therapy. Previously, researchers identified an attenuation in the cholesterol benefits of estrogen by a diminution in highdensity lipoprotein levels in patients on combined estrogen and progestin therapy. Decreases in low-density lipoprotein cholesterol do not appear to be affected by the addition of progestin as documented in the Postmenopausal Estrogen/Progestin Interventions Trial. Concern as to whether women on hormone replacement therapy represent a different subgroup ofpatients does not appear to be substantiated. In general population samples, hormone users, as compared with nonusers, have a higher level of education, leaner body mass, drink more alcohol, and participate in sports more often. These findings were true before their initiation of hormone therapy. This article is reassuring and supports the practice of maintaining progestin therapy in women requiring endometrial hormone control.

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blrogen May Delay Alzheimer's Disease Tang M-X, Jacobs D, Stern Y, Marder K, Schofield P, Gurland B, et al. Effect of oestrogen during menopause on risk and age at onset of Alzheimer's disease. Lancet 1996;

348:429-32.

Synopsis: For this longitudinal study ofaging and health in New York City, 1124 elderly women were evaluated regarding their use of estrogen during the postmenopausal period. These individuals were, at the time of their enrollment, free of Alzheimer's disease. Because estrogen promotes the growth and survival of cholinergic neurons and could decrease cerebral amyloid deposition, the authors theorized that postmenopausal estrogen might delay the onset of or prevent Alzheimer's disease. They found that the age of onset of Alzheimer's disease was significantly higher among the 156 (12.5%) women who reported taking estrogen after the onset of menopause than in those who did not. The relative risk of disease was significantly reduced (nine in 156 [5.8%] estrogen users versus 158 in 968 [16.3%] nonusers). This difference held true after adjustment for differences in education, ethnic origin, and apolipoprotein-E genotype. Duration of estrogen use was found to be predictive. Women who had used estrogen for longer than 1 year had a greater reduction in risk. Of the 23 women who were taking estrogen at the time of study enrollment, none had developed Alzheimer's disease when the article was written.

••• Commentary: This study adds to the armamentarium of expanded benefits of estrogen replacement therapy. The authors further demonstrated that the incidence of Parkinson's disease and cerebral vascular accident was not affected by estrogen use. Their data demonstrate that although estrogen does not prevent Alzheimer's disease, it does seem to delay the onset. Other authors have demonstrated a decrease in severity in estrogen users. T oran-Allerand and colleagues ©1997by the American Pubhshed by