Preserved forearm endothelial responses with acute exposure to progesterone: A randomized cross-over trial of 17-beta estradiol, progesterone, and 17-beta estradiol with progesterone in healthy menopausal women

Regularly menstruating women are relatively protected from cardiovascular disease. Epidemiological and endothelial function studies attribute this protection to estradiol (E(2)), but both progesterone (P) and E(2) are normally present. A range of vascular effects of added progestins have been described, from neutral to detrimental, but the effects of P per se on endothelial function in humans have not been reported. We therefore investigated the acute effects of E(2), P, and E(2) combined with P, on endothelium-dependent and -independent forearm blood flow responses. Using venous occlusion plethysmography, forearm blood flow (FBF) was measured during acute brachial artery infusions, achieving physiologic levels of 17-beta-E(2), P, and 17-beta-E(2) with P in healthy menopausal women with no cardiovascular disease risk factors. Vehicle or hormones were infused, in random order, on 4 days, 1 week apart. Flow responses were measured during coinfusions of hormone with the endothelium-dependent vasodilator acetylcholine and the endothelium-independent vasodilator sodium nitroprusside. Twenty-seven healthy menopausal women were studied, and all had normal baseline endothelial responses. Small ( approximately 15%), statistically nonsignificant increases in endothelium-dependent flow responses were seen after all acute hormone treatments. No impairment in response was seen with P alone or in combination with 17-beta-E(2). In healthy menopausal women without cardiovascular disease risk factors and without baseline defects in endothelial function, acute exposure to physiologic levels of 17-beta-E(2), P, and 17-beta-E(2) with P produced equivalent endothelium-dependent responses. These data suggest that P does not have detrimental vascular effects in humans.     

A scintigraphic comparison of iodine-123-metaiodobenzylguanidine and an iodine-labeled somatostatin analog (Tyr-3-octreotide) in metastatic carcinoid tumors.

A number of neoplasms are known to express somatostatin receptors, and the use of somatostatin receptor imaging in their localization has recently been described. We compared an 123I-labeled somatostatin analog Tyr-3-octreotide (TOCT) and 123I-labeled metaiodobenzylguanidine (MIBG) scintigraphy in seven patients with histologically proven metastatic carcinoid tumors. The optimum time for identifying tumor uptake on scanning after [123I]MIBG was 24-48 hr, and after 123I-TOCT 10-30 min postinjection. Both radiopharmaceuticals showed a varying spectrum of tracer uptake ([123I]MIBG showed no uptake in one patient; minimal in two; moderate in two; and intense in two; 123I-TOCT showed no uptake in two patients; minimal uptake in one; moderate uptake in two; and intense uptake in two). In two patients, 123I-TOCT identified metastatic lesions not seen by [123I]MIBG scintigraphy. These preliminary results suggest that [123I]MIBG and 123I-TOCT are useful and complementary imaging techniques for detecting metastatic carcinoid tumors.     

Pulmonary administration of aerosolised fentanyl: pharmacokinetic analysis of systemic delivery

Aims Pulmonary drug delivery is a promising noninvasive method of systemic administration. Our aim was to determine whether a novel breath-actuated, microprocessor-controlled metered dose oral inhaler (SmartMist^TM, Aradigm Corporation) could deliver fentanyl in a way suitable for control of severe pain.
Methods Aersolised pulmonary fentanyl base 100–300  μg was administered to healthy volunteers using SmartMist^TM and the resultant plasma concentration-time data were compared with those from the same doses administered by intravenous (i.v.) injection in the same subjects.
Results Plasma concentrations from SmartMist^TM were similar to those from i.v. injection. Time-averaged bioavailability based upon nominal doses averaged 100%, and was >50% within 5  min of delivery. Fentanyl systemic pharmacokinetics were similar to those previously reported with no trends to dose-dependence from either route. Side-effects (e.g. sedation, lightheadedness) were the same from both routes.
Conclusions Fentanyl delivery using SmartMist^TM can provide analgetically relevant plasma drug concentrations. This, combined with its ease of noninvasive use and transportability, suggests a strong potential for field and domicilliary use, and for patient controlled analgesia without the need for i.v. cannulae.     

Mean circadian cosinors of vital signs, performance of blood and urinary constituents in patients with leprosy.

We have herewith examined the characteristics of circadian rhythms in patients with lepromatous leprosy, active or inactive, allowing a comparison with corresponding properties of rhythms in healthy subjects mapped earlier. Group results were illustrated by cosinor plots, produced directly on microfilm by computer. Eventually such reference standards in the form of cosinors, among other displays, notably of waveform, may be individualized and carried on a person's health record. Such a quantitative assessment of an individual's rhythms in health may serve for rigorous comparison with any changes accompanying increased susceptibility or occult or overt disease.     

Hemodynamic Drug Interaction: Peridural Lidocaine and Intravenous Ephedrine

Hypotension following peridural anesthesia with lidocaine was treated by intravenous injection of ephedrine. The ephedrine relieved the cardiovascular depression, but was associated with a concomitant increase in plasma lidocaine concentrations. This increase may push the plasma lidocaine concentration into the toxic region.     

Parathyroid adenomas evaluated by Tl-201/Tc-99m pertechnetate subtraction scintigraphy and high-resolution ultrasonography

Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar.     

Plasma levobupivacaine concentrations following scalp block in patients undergoing awake craniotomy

Background. Levobupivacaine is an effective local anaestheticagent for nerve blockade with less systemic toxicity than racemicbupivacaine. The safety and efficacy of levobupivacaine forscalp blockade during awake craniotomy have not been addressedpreviously. Methods. Serial arterial plasma levobupivacaine concentrationsfollowing scalp blockade were measured to 2 h in 10 patientsbooked for awake craniotomy for epilepsy or tumour surgery.Bilateral scalp blockade providing surgical anaesthesia wasachieved with a mean dose of 177 mg (2.5 mg kg^–1, range1.6–3.2 mg kg^–1) of levobupivacaine (0.5%, 5 mgml^–1) with epinephrine (5 µg ml^–1) added immediatelybefore the block insertion. Results. The maximum measured plasma levobupivacaine concentrationwas 1.58 (0.44) µg ml^–1 [mean (SD)] with a meantime to peak plasma concentration of 12 (4) min. There wereno episodes in any of the 10 patients of symptoms or signs suggestiveof either CNS or CVS toxicity. Conclusions. This study demonstrated a relatively rapid riseof plasma levobupivacaine concentration without evidence ofcardiovascular or central nervous system sequelae in a samplepopulation of patients who may be particularly prone to perioperativeseizures.