NIFEDIPINE BLOCKS ACTH AND CORTISOL RELEASE IN MAN

1. The present study investigated the effect of prior administration of nifedipine on AVP-induced ACTH release in seven normal volunteers. Three protocols were used: 20 mg oral nifedipine; 0.14 pressor units intramuscular (i.m.) per kg bodyweight aqueous AVP; oral nifedipine plus i.m. AVP 90 min later. Plasma ACTH and cortisol were measured at intervals for 2.5 h during each test. 2. The mean peak plasma ACTH and cortisol levels and the mean peak changes from basal in these levels were significantly lower in the nifedipine/AVP test than in the AVP alone test. The integrated area under the cortisol time curve was significantly lower for the nifedipine/AVP test than that for the AVP test alone. Nifedipine alone caused no changes in ACTH or cortisol. 3. Acute administration of oral nifedipine caused an inhibition of AVP-stimulated ACTH and cortisol release in normal humans. This effect may be due to blockade of plasma membrane calcium channels normally activated during AVP stimulation of pituitary corticotrophs.     

Use of ultrasound to assess healing of a mandibular distraction wound.

PURPOSE: A standardized, noninvasive technique to assess healing of the mandibular distraction wound is not available. Current methods include clinical examination, plain radiography, and computed tomography. These imaging techniques are expensive and obligate the patient to serial radiation exposure. In addition, anatomic overlap and metal artifacts may obscure the distraction gap. In contrast, ultrasound has been shown to be a noninvasive, efficient, and inexpensive way to evaluate bone healing. The purpose of this study was to test the feasibility of ultrasound to evaluate an experimental mandibular distraction osteogenesis wound. MATERIALS AND METHODS: Distraction devices were placed via a submandibular incision into 24 minipigs. The protocol consisted of 0-day latency and distraction rates of 1, 2, or 4 mm/d for a 12-mm gap. The wounds were assessed in vivo after 0, 8, 16, and 24 days of neutral fixation. Ex vivo radiographs were used to estimate bone fill using a semiquantitative score. A semiquantitative ultrasound score was assigned, and the beam penetration depth was measured in millimeters. RESULTS: In all groups, clinical stability of the distraction wound increased with the duration of fixation. Plain radiographs, taken during neutral fixation, showed that the desired distraction gap was achieved and maintained. The ultrasound score increased with fixation time, whereas beam penetration depth decreased as expected. Ex vivo radiographs showed increasing bone fill score with time and paralleled the ultrasound score. CONCLUSIONS: The results of this feasibility study indicate that ultrasound is potentially useful for the assessment of bone formation in distraction osteogenesis wounds.     

Parental Attitudes Toward Breastfeeding: Their Association with Feeding Outcome at Hospital Discharge

Abstract: Background : A woman chooses to breastfeed for many reasons. Recent research, however, suggests that parental attitudes toward breastfeeding are stronger predictors of infant feeding choice than commonly cited sociodemographic factors. The objective of the current study was to compare the infant feeding attitudes of expectant couples, and to determine to what degree their individual attitudes during early pregnancy were predictive of the method of infant feeding at discharge from hospital. Methods : A convenience sample of pregnant women (gestational age 8–12 weeks), who were attending maternity clinics in Glasgow, Scotland, in 2000, completed the 17‐item Iowa Infant Feeding Attitude Scale (IIFAS), together with their partners. Results : The IIFAS was completed by 108 expectant couples. At discharge from hospital 49.1 percent of women were exclusively breastfeeding, and 50.9 percent were exclusively formula‐feeding. A woman's total infant feeding attitude score was significantly correlated with her partner's score(r = 0.67, p < 0.001). There was no difference in the infant feeding attitudes of formula‐feeding couples(p = 0.987), but breastfeeding women tended to be more supportive of breastfeeding than their partners(p = 0.022). Maternal, but not paternal, infant feeding attitude was a significant predictor of the choice of feeding method (OR = 1.16 95% CI = 1.09–1.24). Conclusions : Infant feeding attitudes tended to be shared by expectant couples. Maternal infant feeding attitude was a better predictor of feeding choice than were demographic factors. Paternal attitudes were not found to be independently associated with feeding choice. Identification of women with neutral infant feeding attitudes using the IIFAS may be an effective way of targeting interventions at those women who are most likely to be receptive to such programs.     

HEMATOCRIT VALUES DURING PREGNANCY IN A NURSE-MIDWIFERY CASELOAD

This article reviews the normal hematologic changes in pregnancy and the kinetics of iron metabolism. The differences between iron depletion and anemia are described. The hematocrit levels of a nurse-midwifery caseload in a tertiary-care setting are described and compared with recently published population norms. Hematocrits of the sample compared favorably to the population hematocrits until 24 weeks' gestation, when the sample hematocrit mean became statistically lower and remained that way throughout pregnancy. Further analysis was done on the sample hematocrits, comparing differences in parity, age, pregnancy spacing, and AS versus AA hemoglobin. Parous women with a pregnancy interval >12 months had a higher mean hematocrit then nulliparous women. Mean hematocrits of age groups varied significantly only at the 29–32-week interval, with women younger than 18 having lower mean hematocrits than those ≥18. A trend of women with AS hemoglobin having higher hematocrits than women with AA hemoglobin was identified, reaching statistical significance at the 29–32-week interval.     

The effect of transportation between the recovery room and intensive care unit on postoperative acoustic tumor patients

Cardiovascular changes have been noted to occur during movement from the operating room or recovery room (RR) to the intensive care unit (ICU). This study examined blood pressure changes and related variables during transport from the RR to the ICU in 135 postoperative acoustic tumor patients. Although there was no significant change in blood pressure values from the RR to the ICU, patients with pre-existing hypertension and elevated RR blood pressures were noted to have an increased frequency of postoperative complications. In addition, a relationship was noted between administration of halothane and frequency of postoperative complications. Results highlight the need for nurses not only to monitor, but also closely control postoperative blood pressure in this population.