Utility of Serum L-lactate in Identifying Ischemia in Acute Intestinal Obstruction: A Prospective Observational Study.

Introduction In cases of intestinal obstruction, increasing luminal dilatation compromises bowel wall perfusion, eventually resulting in intestinal ischemia and bowel necrosis in advanced cases. Elevated L-lactate, as a biomarker of ischemia, may indicate the presence of bowel ischemia in cases of obstruction. The objective of this study was to evaluate the value of serum L-lactate measurement in predicting the presence of intraoperatively observed intestinal ischemia in patients with acute intestinal obstruction. Methods Patients diagnosed with acute intestinal obstruction were prospectively studied over an 18-month period. Serum L-lactate values were assayed twice: at the time of presentation and following appropriate fluid resuscitation. Receiver operating characteristic (ROC) curve analysis was applied to determine the predictive value of serum L-lactate in detecting intestinal ischemia. Results One hundred forty-four cases of intestinal obstruction were included in this study, of which 91 underwent operative intervention. Intestinal ischemia was identified in 52 cases and categorized intra-operatively as reversible (n = 33) and irreversible (n = 19). ROC analysis showed a good predictive value of serum L-lactate after fluid resuscitation for irreversible intestinal ischemia (area under the curve (AUC) = 0.884, 95% confidence interval (CI), 0.812-0.956). An L-lactate cut-off of 19.1 mg/dL following fluid resuscitation was determined to have a sensitivity of 89.5%, a specificity of 72.9%, a positive predictive value of 46.6%, and a negative predictive value of 96.3% for gangrenous bowel. Conclusion Serum L-lactate is a good predictive tool for identifying intestinal ischemia during the management of intestinal obstruction. Serum L-lactate after resuscitation showed better predictive value for ischemic bowel.

Orthostatic hypotension in treated hypertensive patients.

INTRODUCTION: Orthostatic hypotension (OH) is a risk factor for morbidity and mortality and one of the causes of non compliance to treatment among medicated hypertensive subjects. Our objective was to assess the prevalence of OH among treated hypertensive patients and its association with clinical characteristics and antihypertensive drug class. METHODS: This was a cross-sectional study in which we assessed the prevalence of OH, defined according to the American Autonomic Society and American Academy of Neurology guidelines, among adult treated hypertensive patients who performed a home blood pressure monitoring at our institution. We also determined the prevalence of OH according to age group (< 65, 65-79 and > 80), antihypertensive drug class, office and home hypertension control status. RESULTS: We included 302 medicated patients in the study. Mean age was 66.6 (+13.8), 67% were women. We found a 9.7% global prevalence of OH, which was significantly higher among older individuals (3.6% among patients < 65 years-old, 12.2% in the 65-79 year-old group and 16.7% among octogenarians, p = 0.02) and those who consumed alpha-blockers (75 vs. 8.5%, p < 0.01). Uncontrolled hypertensive patients at office and/or at home had also a significantly higher prevalence of OH: uncontrolled vs. controlled office blood pressure (BP), 14.3 vs. 6.5%, p = 0.03 and uncontrolled vs. controlled home BP, 15.1 vs. 6.6%, p = 0.02. Remarkably, 64% of patients with OH had their BP under control when considering office-standing BP. CONCLUSION: OH is a prevalent entity among treated hypertensive patients and systematic measurement of standing BP should be mandatory in the evaluation of these patients.

Current strategies to achieve further cardiac and renal protection through enhanced renin-angiotensin-aldosterone system inhibition.

An incomplete inhibition of the renin angiotensin aldosterone system (RAAS) may be responsible for the residual organ damage and event rate that still occur in spite of an apparent blood pressure control in patients with hypertension, diabetes, chronic kidney disease and heart failure treated with angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB). Additional antiproteinuric effect in diabetic and non diabetic chronic kidney disease, and reduction in hospitalizations in patients with heart failure already receiving a single RAAS antagonist, has been achieved by incremental inhibition of the RAAS with dual therapy or uptitration of an individual agent above conventional dosages. However, the synergistic increase in plasma renin activity (PRA) and the angiotensin II escape could reduce the expected benefit obtained with dual therapy. Results from ONTARGET showing a lack of additional outcome benefit over monotherapy, with a concomitant increase risk of hyperkalemia, renal impairment, and hypotension, discourage the use of the ACEI/ARB combination in patients at high risk of cardiovascular events. This occured despite a lower albumin excretion in dual versus single RAAS blockade, indicating that an incremental antiproteinuric effect is not automatically translated into clinical outcome benefits. The efficacy and safety of ACEI/ARB combination versus monotherapy in patients with overt proteinuria is currently evaluated by LIRICO and VA NEPHRON-D clinical trials. The long lasting direct renin inhibitor aliskiren, acting at the first and rate limiting step of the RAAS cascade, prevents the reactive increase in PRA when combined with ACEIs, ARBs or diuretics. The ASPIRE HIGHER programme, involving more than 35,000 patients with hypertension, heart failure, kidney disease and diabetes, is currently evaluating the efficacy and safety of aliskiren on top of standard therapy. The clinical benefit of adding mineralocorticoid receptor blockers (MRBs) in the control of resistant hypertension, proteinuric kidney diseases, and prevention of mortality in patients with heart failure on top of conventional treatment, evidences the pathogenic role of inadequately suppressed aldosterone as a cause of suboptimal response to conventional RAAS inhibition. The present review will focus on the pathophysiological ground, and the evidence provided by clinical trials assessing the efficacy and safety of recent strategies for the prevention of cardiovascular events and target organ damage progression via enhanced RAAS inhibition.

Laparoscopic management of an uncommon cause for right lower quadrant pain: A case report.

INTRODUCTION: Primary segmental infarction of the greater omentum is an infrequent cause for right lower quadrant pain. The exact aetiology is unknown and the right side is more commonly involved. It usually presents like acute appendicitis and the diagnosis is made during exploration. CASE REPORT: We report such a case which was diagnosed and managed by laparoscopy. A 27-year-old male presented with features suggestive of acute appendicitis. Preoperative imaging failed to diagnose the condition. Laparoscopy showed a segment of oedematous and haemorrhagic greater omentum adherent to the parietal wall over the right lower quadrant. The infarcted segment was excised and removed in a non permeable bag through the umbilical port. A short edited video of the operative findings and the procedure executed is also provided. CONCLUSION: Primary segmental infarction of the greater omentum is an uncommon cause of right lower quadrant pain mimicking appendicitis. Laparoscopy is both diagnostic as well as therapeutic.

Laparoscopic mesh splenopexy (sandwich technique) for wandering spleen.

BACKGROUND: Wandering spleen is a rare clinical condition caused by incomplete fusion of the 4 primary splenic ligaments, allowing the spleen to be mobile within the abdomen, predisposing to splenic torsion along the vascular pedicle leading to splenomegaly and infarction, often diagnosed in an emergency setting. METHODS: The wandering spleen diagnosis was achieved by ultrasound in our case. We successfully treated the patient with laparoscopic splenopexy because the size was almost normal, and no infarction or evidence of hypersplenism was present. We used the sandwich technique in which 2 meshes sandwich the spleen. RESULTS: This technique was found to be highly satisfactory as a treatment for wandering spleen. The patient was discharged on the third postoperative day with no intraoperative or postoperative complications. CONCLUSION: Laparoscopy usually confirms the diagnosis. Recommended surgical procedures are splenopexy or splenectomy. Splenopexy is feasible, less invasive, and does not diminish splenic function.

Laparoscopic repair of high rectovaginal fistula: is it technically feasible?

BACKGROUND: Rectovaginal fistula (RVF) is an epithelium-lined communication between the rectum and vagina. Most RVFs are acquired, the most common cause being obstetric trauma. Most of the high RVFs are repaired by conventional open surgery. Laparoscopic repair of RVF is rare and so far only one report is available in the literature. METHODS: We present a case of high RVF repaired by laparoscopy. 56-year-old female who had a high RVF following laparoscopic assisted vaginal hysterectomy was successfully operated laparoscopically. Here we describe the operative technique and briefly review the literature. RESULTS: The postoperative period of the patient was uneventful and after a follow up of 6 months no recurrence was found. CONCLUSION: Laparoscopic repair of high RVF is feasible in selected patients but would require proper identification of tissue planes and good laparoscopic suturing technique.

Secretory carcinoma of breast in a 17-year-old male.

BACKGROUND: Secretory carcinoma of the male breast (juvenile carcinoma) is a rare neoplasm. Only a few cases have been reported in the literature. CASE REPORT: We report here a case in a 17-year old male presenting with recurrent breast swelling. CONCLUSIONS: Though considered an indolent neoplasm, secretory carcinoma does metastasise to lymph nodes and recur after local excision. Surgery in form of mastectomy with axillary clearance is the treatment of choice.

Unsuspected hyperhomocysteinemia in chronically anticoagulated patients.

Hyperhomocysteinemia is a risk factor for arterial and venous thrombosis. The aim of this study was to evaluate plasmatic homocysteine levels in patients under chronic anticoagulant treatment with dietary restriction of green vegetables. This kind of food is a very important source not only of vitamin K but also of folates, which are involved in Hcy metabolism. It is known that the lower the folate levels, the higher the Hcy concentration, so we suspected that these patients could show hyperhomocysteinemia. A group of patients receiving oral anticoagulant treatment and a restricted diet (Group I, n = 20) was compared with a group of untreated subjects of a similar age that were not on a restricted diet (Group II, n = 35). Group I showed significantly higher levels of plasmatic Hcy and significantly lower levels of serum folate than Group II. Therefore, a diet restricted in vitamin K applied to oral anticoagulated patients could induce an unwanted increase of homocysteine levels.

Contribution of stroke volume to the change in pulse pressure pattern with age.

This study investigated the effect of age on pulse pressure and its underlying mechanisms in unmedicated hypertensive men with the same level of mean arterial pressure. We included 77 men 17 to 76 years old with daytime mean arterial pressure between 95 and 114 mm Hg. In the supine position, pulse pressure showed a significant widening in young (<30 years) and older (>/=60 years) patients. Pulse pressure decreased in parallel with stroke index from age >30 to 40 to 49 years. Upright posture, however, eliminated this difference through a larger orthostatic fall in stroke index and pulse pressure in the youngest patients. After age 50 years, pulse pressure exhibited a progressive widening despite the further age-related decrease in stroke index. Supine, upright, and 24-hour pulse pressure fitted a curvilinear correlation with age (r=0.55, 0.56, and 0.68, respectively, P<0.001), with a transition at age 50 years. Before age 50 years, 24-hour pulse pressure correlated positively with stroke volume (r=0.5, P<0.001) and negatively with arterial compliance (SV/PP ratio, r=-0.37, P<0.01). In contrast, in men >/=50 years old, 24-hour pulse pressure correlated negatively with the SV/PP ratio (r=-0.5; P<0.01), without significant influence of stroke volume. Thus, in hypertensive men, the age-related change in stroke volume significantly accounted for the change in clinic and ambulatory pulse pressure during young adulthood, but its contribution decreased after the fifth decade.

Lack of effective blood pressure control among an elder hypertensive population in Buenos Aires.

Our purpose was to determine the level of awareness, treatment, and control of hypertension in a population of subjects aged 65 or more. We studied a random sample from the national health care program in Buenos Aires. Letters were mailed to 1000 selected individuals. Among those eligible, 41.4% (n = 414) were enrolled. The mean age was 73.8 years and 68% were women. Prevalence of hypertension in our sample was 77.5% (n = 321). Awareness of hypertension was 60.7% (n = 195). Fifty-four percent (n = 173) of the hypertensive subjects were receiving pharmacologic treatment and only 18.5% (n = 32) of them were controlled. These results show that there is a low level of awareness, pharmacologic treatment, and control of hypertension in the studied elderly subjects.

Diastolic pressure underestimates age-related hemodynamic impairment.

It has been hypothesized that as large arteries become more rigid with age, the pattern of hypertension changes from diastolic to systolic. Thus, diastolic blood pressure (DBP) may lose its ability to reflect the increase in vascular resistance with age. To assess this, we studied the age-related changes in blood pressure pattern and its steady-state and pulsatile determinants. We performed an epidemiological analysis based on a national survey of 10,462 subjects from Argentina. A hemodynamic analysis (impedance cardiography) was then carried out in 636 consecutive hypertensive patients (age, 25 to 74 years). Whereas the rate of increment in the prevalence of mild to moderate hypertension (MMH) reached a plateau after the sixth decade, isolated and borderline systolic forms of hypertension began a steep and sustained rise. Among patients with MMH, DBP remained stable from the third to the seventh decade, whereas SBP maintained a sustained increase. Despite similar DBP, the systemic vascular resistance index increased 47% (P<.01) and the cardiac index decreased 27% (P<.01), whereas the ratio of stroke volume to pulse pressure, an index of arterial compliance, decreased 45% (P<.01). However, there were no significant differences between older patients with MMH and those with isolated systolic hypertension in the level of SBP, vascular resistance, stroke volume, and cardiac index. Compared with age-matched normotensive control subjects, the ratio of stroke volume to pulse pressure was much more reduced in isolated systolic hypertension (48%) than in MMH (30%). In summary, the present study, carried out in a large sample of hypertensive subjects with a wide age range, showed a simultaneous impairment in vascular resistance and arterial compliance associated with aging in different patterns of hypertension. The magnitude of these changes, with opposite effects on DBP but additive effects on SBP, suggests that a hemodynamic mechanism could determine the transition in the prevalence of diastolic hypertension toward a systolic pattern of hypertension with aging. Also, the results suggest that SBP, but not DBP, is a reliable indicator of the underlying hemodynamic abnormalities (high resistance and low arterial compliance) in the elderly.

Hemodynamic effects of transdermal estradiol alone and combined with norethisterone acetate.

A 24 weeks, randomized, two-period, placebo controlled study was conducted to compare the effects of continuous transdermal 17 beta-estradiol replacement therapy (0.05 mg/day once a week) with placebo on systemic hemodynamics and blood pressure in postmenopausal women. Twenty-nine postmenopausal women (47-62 years) free of hormone replacement therapy were randomized in two groups; group 1 received estradiol patches for the first 12 weeks and placebo patches for the second, and group 2 received the same treatments in the reverse order. The effect of combined estradiol plus oral norethisterone acetate (NETA) 1 mg was also evaluated in the subset of women with intact uteri (n = 24). Crossover analysis showed that stroke volume and cardiac output were significantly higher (P < 0.05) and blood pressure was significantly lower (P < 0.05) with estradiol, irrespective of the order in which the treatments were administered. Although correlations between plasma estradiol levels during active treatment and hemodynamic changes were not significant, hemodynamic changes were significantly greater above 63 pg/ml than below this level (P < 0.05). Oral norethisterone acetate administration either during transdermal placebo or estradiol arms tended to modify systemic hemodynamics in the same direction than estradiol but the changes did not attained statistical significance. In summary compared with placebo, transdermal 17 beta-estradiol, replacement to postmenopausal women, increased cardiac output and decreased blood pressure. Although the average magnitude of changes was small, the results suggest that plasma estradiol levels could be a source of individual variability in the hemodynamic response. Oral NETA administration tended to enhance rather than reverse the estradiol-induced changes.

Influencia de la siesta sobre la presión arterial en pacientes hipertensos esenciales / Afternoon nap influence on blood pressure in essential hypertensives

Hay suficientes evidencias que demuestran que el descenso nocturno de la presión arterial es consecuencia de la inactividad y no depende de una hora determinada, ya que la presión arterial desciende cuando los individuos duermen durante el día. Comparamos la presión arterial sistólica, diastólica y la frecuencia cardíaca durante la siesta, el período nocturno de actividad y el sueño nocturno en 59 pacientes (32 mujeres, 27 hombres) hipertensos sin medicación (edad promedio: 53 ñ 14 años, rango: 26-84 años). La presión arterial y la frecuencia cardíaca fueron registradas utilizando un Pressurometer Del Mar IV 1990. Veintidós pacientes durmieron dos horas por lo menos luego de almorzar, 17 descansaron sin dormir y 20 permanecieron activos en el período posprandial. Evaluamos la media, el área bajo la curva y el desvío estándar de la presión arterial sistólica, diastólica y frecuencia cardíaca durante el período posprandial, el sueño nocturno y el resto del día. Tanto el sueño nocturno como el sueño posprandial disminuyeron la presión arterial sistólica, diastólica y la frecuencia cardíaca. Durante el descanso posprandial la presión arterial diastólica fue similar a la presión arterial diastólica nocturna y durante la siesta disminuyó más que durante el sueño nocturno

Influencia de la siesta sobre la presión arterial en pacientes hipertensos esenciales / Afternoon nap influence on blood pressure in essential hypertensives

Hay suficientes evidencias que demuestran que el descenso nocturno de la presión arterial es consecuencia de la inactividad y no depende de una hora determinada, ya que la presión arterial desciende cuando los individuos duermen durante el día. Comparamos la presión arterial sistólica, diastólica y la frecuencia cardíaca durante la siesta, el período nocturno de actividad y el sueño nocturno en 59 pacientes (32 mujeres, 27 hombres) hipertensos sin medicación (edad promedio: 53 ñ 14 años, rango: 26-84 años). La presión arterial y la frecuencia cardíaca fueron registradas utilizando un Pressurometer Del Mar IV 1990. Veintidós pacientes durmieron dos horas por lo menos luego de almorzar, 17 descansaron sin dormir y 20 permanecieron activos en el período posprandial. Evaluamos la media, el área bajo la curva y el desvío estándar de la presión arterial sistólica, diastólica y frecuencia cardíaca durante el período posprandial, el sueño nocturno y el resto del día. Tanto el sueño nocturno como el sueño posprandial disminuyeron la presión arterial sistólica, diastólica y la frecuencia cardíaca. Durante el descanso posprandial la presión arterial diastólica fue similar a la presión arterial diastólica nocturna y durante la siesta disminuyó más que durante el sueño nocturno (AU)

Relationship between systemic hemodynamics and ambulatory blood pressure level are sex dependent.

Sex-related differences in systemic hemodynamics were analyzed by means of cardiac index and systemic vascular resistance according to the level of daytime ambulatory blood pressure. In addition, we assessed the relations between ambulatory blood pressure measurements and systemic hemodynamics in male and female patients. We prospectively included 52 women and 53 men referred to our unit for evaluation of arterial hypertension. Women and men were grouped according to the level of daytime mean arterial pressure: < 110 or > or = 110 mm Hg. Patients underwent noninvasive evaluation of resting hemodynamics (impedance cardiography) and 24-hour ambulatory blood pressure monitoring. Compared with women men with lower daytime blood pressure had a 12% higher systemic vascular resistance index (P = NS) and a 14% lower cardiac index (P < .02), whereas men with higher daytime blood pressure had a 25% higher vascular resistance (P < .003) and a 21% lower cardiac index (P < .0004). Furthermore, in men systemic vascular resistance correlated positively with both daytime and nighttime systolic and diastolic blood pressures, whereas cardiac index correlated negatively only with daytime diastolic blood pressure. In contrast, women did not exhibit any significant correlation between hemodynamic parameters and ambulatory blood pressure measurements. In conclusion, sex-related differences in systemic hemodynamics were more pronounced in the group with higher daytime hypertension. The relations between systemic hemodynamics and ambulatory blood pressure level depended on the sex of the patient. In men a progressive circulatory impairment underlies the increasing level of ambulatory blood pressure, but this was not observed in women.

Glutamic acid decarboxylase in different areas of the developing chick central nervous system.

The temporal course of the development of GAD activity in GABAergic neurons was studied in the chick retina, optic lobe and cerebellum. The developmental pattern of GAD activity was similar in the three areas studied, showing typical sigmoideal curves, which reached a maximal value at the 3rd post-hatching day. Kinetic studies during development revealed that Km remained unchanged while Vmax increased 3-fold in the retina (48.99 +/- 0.84 nmol/hr/mg protein), almost 4-fold in the optic lobe (162.77 +/- 4.32 nmol/hr/mg protein) and 3.5 fold in the cerebellum (69.30 +/- 1.26 nmol/hr/mg protein). The developmental pattern of GAD activity in homogenates of the three areas studied from dark-reared and light-reared chicks with respect to normal light-dark cycle animals showed no significant differences. These results indicate that the increase in GAD activity during development are not due to a change in the affinity for its substrate but rather to changes in the concentration of the enzyme. The developmental pattern of GAD activity in the chick visual system was not affected by environmental conditions suggesting that the developmental profile is light-independent.

Light and dark adaptation influences GABA receptor sites in the chick retina.

The aim of the present study was to investigate the effect of environmental conditions such as light-and-dark-adaptation on the plasticity of GABA receptor sites in the chick retina. In chicks exposed to light for 5 hr (light-adapted), specific [3H]GABA binding was increased by 35% in comparison to the binding found in chicks maintained in darkness (dark-adapted). Conversely, in the retina of chicks exposed to darkness for 5 hr, specific [3H]GABA binding was decreased by 28% with respect to that found in chicks kept in the light. Scatchard analysis of the binding data revealed that the affinity of GABA for its receptor binding site was higher in the retinas of light-adapted chicks than in those of dark-adapted chicks (Kd values of 19.20 +/- 1.23 and 27.20 +/- 1.47 nM, respectively). On the contrary, the maximal number of binding sites (Bmax) remained unchanged in light- and dark-adapted chicks (5.2 +/- 0.10 and 5.3 +/- 0.15 pmol/mg protein, respectively). These results suggest the involvement of GABA receptors in the regulation of visual function.