Intraaortic balloon tamponade during hemorrhagic shock in sheep

Two groups (n = 10 in each) of adult sheep were exposed to hemorrhagic shock resulting in mean arterial pressure (MAP) below 25 mmHg for 10 min. Following that, group A received crystalloids (8% of body wt) during one hr together with supraceliac intraaortic balloon tamponade during the first 30 min, while group B (controls) received crystalloids only. The central circulation was rapidly restored in group A, as indicated by increased MAP and increased systemic vascular resistance (SVR). After deflation of the balloon MAP dropped to the same value as in the control group, while cardiac index increased gradually with volume replacement and was significantly higher at the end of the resuscitation period (60 min) than in the control group (P less than 0.05). Despite a more rapid restoration of central hemodynamics in group A, lactic acidosis was more severe, acute renal failure and neurological complications more frequent, and mortality higher than in the control group. It was concluded that continuous supraceliac aortic occlusion for 30 min had deleterious effects on organs dependent on aortic blood flow distal to the aortic tamponade and may contribute to the development of multiple organ failure after resuscitation from hemorrhagic shock. Further studies are needed to evaluate the effects of intermittent intraaortic balloon tamponade in hemorrhagic shock.     

Successful treatment of failed AID cases by use of gamete intra-fallopian transfer using donor semen (GIFT (D)).

Over a 13-month period in a newly opened assisted conception unit at the Women's Hospital, Liverpool, gamete intra-fallopian transfer using donor semen, GIFT (D) was offered to eighteen couples who had failed to conceive after numerous cycles of treatment with artificial insemination by donor semen (AID). The indication for the use of donor semen was either azo- or severe oligoaesthenospermia, and, in addition, the female partners have been exhaustively investigated with no major cause found to account for the couple's infertility. Using a basic clomiphene citrate and human menopausal gonadotrophin protocol it was possible to achieve a pregnancy rate of 56% per GIFT (D) cycle. As a consequence of these results it is now our policy to treat couples whose infertility is due to an unresolvable male factor with AID for 12 cycles only. If they have been unsuccessful in achieving a pregnancy after this time, they are offered GIFT (D).     

Adrenal magnetic resonance imaging in addison’s disease

Magnetic resonance imaging of the adrenal glands was performed in 9 patients with Addison’s disease to evaluate the role of magnetic resonance (MR) in this entity. All patients had bilateral adrenal masses demonstrated by computed tomography (CT); etiologies included adrenal hemorrhage (2 patients), granulomatous disease (1 patient), adrenal lymphoma (3 patients), and adrenal metastases (3 patients). Spin-echo axial images were obtained at repetition times (TR) 0.5, 2.0 s and TE 28, 56 ms, using a Diasonics superconducting magnet operating at 0.35 T. In the patients with lymphoma, metastases, and granulomatous disease, the adrenal masses appeared hypointense or isointense with liver on the T₁-weighted images (TR 0.5 s, TE 28 ms). In cases of adrenal hemorrhage, areas of hyperintensity were seen on TR 0.5, TE 56 ms sequences, due to shortening of T₁ values. In both groups of patients the masses were hyperintense on T₂ weighted sequences. Mean calculated T₁ of the hemorrhagic glands was 449 ms, compared with a mean of 782 ms for mestastases and lymphoma. While MR is not capable of distinguishing between acute inflammatory and metastatic disases of the adrenal glands, it may be equally efficacious as CT in suggesting the diagnosis of adrenal hemorrhage in patients with Addison’s disease.     

Receptors for angiotensins I and II: their relevance to renal haemodynamics, blood pressure control and hind-limb blood flow.

The well established differential pulmonary handling of angiotensins I and II indicates the possibility that vascular receptors for the deca- and octa-peptides do not necessarily involve common sites in the renal vasculature either. Experimental findings involving haemodynamic changes within the kidney in anaesthetised and conscious sheep, with utilization of the angiotensins, and also of noradrenaline, are briefly presented; the implications of the intra-renal water and creatinine transfers are discussed, especially as they concern the possible location of angiotensin receptors in the renal blood vessels. Other aspects of the relationships between the peptides are also taken into account particularly with regard to a postulated angiotensin I [NaCl] dependent peritubular capillary antidiuretic action, angiotensin converting enzyme inhibition, Goldblatt clamp induced hypertension and blood flow through the hind-limbs.     

Effect of acclimation on resting energy expenditure measurements.

BACKGROUND: Development of an acclimation protocol for use when measuring resting energy expenditure (REE) would simplify and standardize data collection. The purpose of this study was to determine if our 2 metabolic carts could be used interchangeably and to determine if excluding the first 3 or 5 minutes of data collected as an acclimation period would significantly improve the coefficients of variation (CVs) for oxygen consumed (VO(2)) and carbon dioxide produced (VCO(2)) when performing REE assessments with our metabolic cart systems. METHODS: Thirteen healthy, nonsmoking adults ranging in age from 32 to 45 years, with activity levels ranging from sedentary to highly active, participated. Indirect calorimetry was performed twice in the morning after 30 minutes of supine resting. Subjects had fasted for 12 hours, and did not exercise within the last 24 hours. The system order for testing was randomized for the first measurement. When the first measurement was completed, subjects were crossed over for measurement using a second metabolic cart. RESULTS: The CVs for VO(2) and VCO(2) were significantly lower when excluding the first 3 (VO(2), p = .0005), (VCO(2), p = .0024) or 5 minutes (VO(2), p = .0001, VCO(2), p = .0021) of data compared with no exclusions. No significant differences in CVs between the 3- and 5-minute exclusions were found for VO(2) (p = .3224) or VCO(2) (p = .2255). CONCLUSIONS: Clearly, our machines cannot be used interchangeably within a study. An acclimation period improves CVs of VO(2) and VCO(2.) The similarities in CVs led us to adopt a 3-minute acclimation period for measuring REE.     

Preliminary assessment of the Dex Frame for assisting children with specific learning difficulties

A device called the Dex Frame has recently been marketed as an aid for children with specific learning difficulties. Using a test of reading speed and a test of reading accuracy we have attempted to evaluate the device. Two groups of children with learning difficulties were used, one having sole use of the device and being allowed to carry it with them and a second group who only used the device when attending for remedial tuition and assessment. The results show that no significant improvement occurred in reading performance of the groups with learning difficulties using the Dex Frame as compared with a control group. The teachers of the groups did, however, feel that on an individual basis some children (< 10%) expressed that they felt more comfortable using the device.