Posthepatectomy liver failure after simultaneous versus staged resection of colorectal cancer and synchronous hepatic metastases.

BACKGROUND: Posthepatectomy liver failure (PHLF) is the third most frequent complication and the major cause of postoperative mortality after resection of colorectal cancer liver metastases (CRLM). In case of synchronous resectable CRLM, it is still unclear if surgical strategy (simultaneous versus staged resection of colorectal cancer and hepatic metastases) influences the incidence and severity of PHLF. The aim of this study was to evaluate the impact of surgical strategy on PHLF and on the early and long-term outcome. PATIENTS AND METHODS: Retrospective study on 106 consecutive patients undergoing hepatectomy for synchronous CRLM between 1997 and 2012. RESULTS: Of 106 patients, 46 underwent simultaneous resection and 60 had staged hepatectomy. The rate of PHLF was similar between groups (16.7% vs 15.2%; p=1) and subgroup analysis restricted to patients undergoing major hepatectomy confirmed this observation (31.8% vs 23.8%; p=0.56). Propensity-score analysis showed that preoperative total bilirubin level and the amount of intra-operative blood transfusion were independently associated with an increased risk of PHLF. Nevertheless, the risk of severe PHLF (grade B - C) was increased in patients who underwent simultaneous resection and major hepatectomy (OR: 4.82; p=0.035). No significant differences were observed in severe (Dindo - Clavien 3 - 4) postoperative morbidity (23.9% vs 20.0%; p=0.64) and survival (3 and 5-year survival: 55% and 34% vs 56% and 33%; p=0.83). CONCLUSIONS: The risk of PHLF is not associated with surgical strategy in the treatment of synchronous CRLM. Nevertheless, the risk of severe PHLF is increased in patients undergoing simultaneous resection and major hepatectomy.

The airborne transmission of infection between flats in high-rise residential buildings: Tracer gas simulation.

Airborne transmission of infectious respiratory diseases in indoor environments has drawn our attention for decades, and this issue is revitalized with the outbreak of severe acute respiratory syndrome (SARS). One of the concerns is that there may be multiple transmission routes across households in high-rise residential buildings, one of which is the natural ventilative airflow through open windows between flats, caused by buoyancy effects. Our early on-site measurement using tracer gases confirmed qualitatively and quantitatively that the re-entry of the exhaust-polluted air from the window of the lower floor into the adjacent upper floor is a fact. This study presents the modeling of this cascade effect using computational fluid dynamics (CFD) technique. It is found that the presence of the pollutants generated in the lower floor is generally lower in the immediate upper floor by two orders of magnitude, but the risk of infection calculated by the Wells-Riley equation is only around one order of magnitude lower. It is found that, with single-side open-window conditions, wind blowing perpendicularly to the building may either reinforce or suppress the upward transport, depending on the wind speed. High-speed winds can restrain the convective transfer of heat and mass between flats, functioning like an air curtain. Despite the complexities of the air flow involved, it is clear that this transmission route should be taken into account in infection control.

[Day Surgery. Five years of experience and activity]. / Day Surgery. Nostra esperienza dopo 5 anni di attività

BACKGROUND: The aim of this paper is to evaluate the management of an integrated unit of Day Surgery in a General Surgery Department. METHODS: An outline of the first 5 years of activity is presented. Setting of investigation: little provincial hospital. Patients have been selected on a basis of Day Surgery specific features: a total of 1,294 patients. Pathologies treated: inguinal hernias, phlebectasias, phimosis, borsitis, arthritic cysts, tendon cysts, carpal tunnel, Dupuytren's disease ("crispatura tendinum"), lymphadenitis, mammary nodules, hemorrhoids, hydroceles, varicoceles, adipomas. Patients' selection parameters, surgical operation type and modalities, postoperative course, protected discharges from hospital, follow-up and complications have all been carefully recorded. RESULTS: The most numerous operations were related to hernial pathology (54.32%) and to adipomas (10.81%). The form of anesthesia was mainly loco-regional. Only 4 cases (0.3%) had to be hospitalized for the night after operation. COMPLICATIONS: 1 serious wound infection, needing removal of the hernial prosthesis; 1 painful "tumefaction" on the inguinal wound for hernioplastic operation; 3 "seromas" in inguinal hernioplastics. CONCLUSIONS: Advantages of Day-Surgery: cut in health costs due to the reduction of admissions to hospital; reduction in hospital infections and in surgical wounds; reduction in drug use; thinning of waiting lists; increase of available beds for other pathologies; reduction of disability days; high appreciation index.

Algogenic effects of the proximal and distal intracoronary infusion of adenosine. Pathophysiologic implications on the mechanisms of ischemic cardiac pain.

BACKGROUND: It has been hypothesized that ischemic cardiac pain might be due to a spatially restricted intense stimulation of non-specific cardiac receptors. If this hypothesis is correct a strong stimulation with an adequate stimulus of a limited myocardial region should cause more pain than a weaker stimulation of a larger myocardial region. METHODS: To test this hypothesis, we carried out a systematic study in 8 male patients (mean age 52 +/- 9 years) with uncomplicated stable angina pectoris and significant isolated proximal left anterior descending coronary artery stenosis in whom the same amount of adenosine, a known mediator of cardiac and muscular ischemic pain, was infused at the proximal and distal site of the left anterior descending coronary artery. Increasing doubling doses (from 108 to 3456 micrograms/min) or adenosine were infused for periods of 2 min each into the left anterior descending coronary artery through a 2.8 F catheter. Adenosine was infused in each patient both proximally to the first diagonal branch and distally to the last diagonal branch of the left anterior descending coronary artery. The initial infusion site, proximal or distal, was randomized. At the beginning of the study patients were asked to promptly report the onset of pain. Time to onset of adenosine-induced pain and maximal pain severity (assessed by a visual analog scale) were recorded. Twelve electrocardiographic leads were recorded throughout the study. RESULTS: Seven patients experienced pain during adenosine infusion both at the proximal and distal level. One patient experienced pain only during adenosine infusion at the proximal site. In all patients pain occurred earlier (176 +/- 125 vs 343 +/- 207 s, p = 0.005) and its severity was greater (51 mm, range 20-95, vs 27 mm, range 0-69, p = 0.002) during infusion at the proximal site. No patient exhibited electrocardiographic changes during the study. CONCLUSIONS: Adenosine infusion at a proximal coronary site causes pain which occurs earlier and is more severe than that experienced during its infusion at a distal site. These findings suggest that the intensity of ischemic cardiac pain is determined by the number of stimulated receptors rather than by the intensity of their stimulation.

Luteal phase support with 17alpha-hydroxyprogesterone versus unsupported cycles in in vitro fertilization: a comparative randomized study.

This study was designed to determine the efficacy of 17alpha-hydroxyprogesterone caproate (17-OHPc) for luteal phase support in in vitro fertilization (IVF). For this purpose, a total of 86 IVF patients undergoing embryo transfer were randomly allocated to two groups as follows: (1) group A, including 43 patients who received the support of luteal phase through the intramuscular administration of 17-OHPc at a dosage of 341 mg every 3 days, and (2) group B, including 43 patients who received the intramuscular administration of a saline solution as placebo every 3 days. In both groups, the treatment was started within 24 h after embryo transfer until beta-HCG evaluation. In case of positive beta-HCG, it was extended until 12 weeks. Efficacy was assessed using the pregnancy rates, which was, per transfer, statistically significantly higher in group A than in group B (32.5 vs. 18.3% respectively). On the basis of our results, we emphasize the use of 17-OHPc for luteal phase support after IVF and embryo transfer.

Effects of K(ATP) channel blockade by glibenclamide on the warm-up phenomenon.

AIMS: The increased tolerance to myocardial ischaemia observed during the second of two sequential exercise tests, i.e. the warm-up phenomenon, has been proposed as a clinical model of ischaemic preconditioning. As ATP-sensitive K+ channels appear to be a mediator of ischaemic preconditioning in both experimental and clinical studies, the aim of this study was to investigate the role of K(ATP) channels in the warm-up phenomenon. METHODS AND RESULTS: Twenty-six patients with coronary artery disease were randomized to receive 10 mg oral glibenclamide, a selective ATP-sensitive K+ channel blocker, or placebo. Sixty minutes after glibenclamide or placebo administration, patients were given an infusion of 10% dextrose (8 ml x min(-1)) to correct glucose plasma levels or, respectively, an infusion of saline at the same infusion rate. Thirty minutes after the beginning of the infusions, both patient groups underwent two consecutive treadmill exercise tests, with a recovery period of 15 min to re-establish baseline conditions. Before exercise tests, blood glucose levels were similar in placebo and glibenclamide groups (96 +/- 10 vs 105 +/- 22 mg x 100 ml(-1), P=ns). After placebo administration, rate-pressure product at 1.5 mm ST-segment depression significantly increased during the second exercise test compared to the first (220 +/- 41 vs 186 +/- 29 beats x min(-1) x mmHg x 10(2), P<0.01), but it did not change after glibenclamide (191 +/- 34 vs 187 +/- 42 beats x min(-1) x mmHg x 10(2), P=ns), with a significant drug-test interaction (P=0.0091, at two-way ANOVA). CONCLUSIONS: Glibenclamide, at a dose previously shown to abolish ischaemic preconditioning during coronary angioplasty, prevents the increase of ischaemic threshold observed during the second of two sequential exercise tests. These findings confirm that ischaemic preconditioning plays a key role in the warm-up phenomenon and that in this setting is, at least partially, mediated by activation of ATP-sensitive K+ channels.

Intramuscular versus vaginal administration of progesterone for luteal phase support after in vitro fertilization and embryo transfer. A comparative randomized study.

A total of 156 patients were randomly treated with exogenous natural progesterone (intramuscularly, 50 mg/day) and vaginal gel (90 mg/day) P or nothing (Controls) from the day before embryo transfer (ET) for two weeks. In case of positive beta-HCG, the treatment was continued for 12 weeks. Plasma P and 17 beta-Estradiol concentrations were estimated and compared with the control not supplemented group. Both treatments were able to increase significantly the luteal plasmatic values of P versus controls. The ongoing pregnancy and the living birth rates per transfer were significantly higher in the patients supplemented with intramuscular P than in those treated with vaginal gel P. The intramuscular natural P appears the most suitable route of administration for luteal phase support in IVF-ET procedures.

Effects of A1 adenosine receptor blockade on the warm-up phenomenon.

The increased tolerance to myocardial ischemia observed during the second of two sequential exercise tests, i.e. the warm-up phenomenon, has been proposed as a clinical model of ischemic preconditioning. Adenosine appears to be a mediator of ischemic preconditioning in both experimental and clinical settings. The purpose of this study was to investigate the role of A1 adenosine receptors in the warm-up phenomenon. A double-blind, placebo-controlled, cross-over design was used. Twelve patients with coronary artery disease and positive exercise test were randomized to receive either bamiphylline, a selective A1 adenosine receptor antagonist, or placebo, immediately prior to two consecutive treadmill exercise tests carried out on day 1. Then, on day 2 all patients underwent two consecutive exercise tests immediately after administration of the remaining treatment. During the first exercise test, bamiphylline, compared to placebo, increased the time to and rate-pressure product at 1.5 mm ST-segment depression (from 317 +/- 118 to 423 +/- 127 s, p < 0.05 and from 199 +/- 38 to 230 +/- 36 b/min.mmHg.10(2), p < 0.05, respectively). After both placebo and bamiphylline infusions, time to 1.5 mm ST-segment depression during the second exercise test was greater than that during the first test (445 +/- 121 vs 317 +/- 118 s, p < 0.001 and 483 +/- 128 vs 423 +/- 127 s, p < 0.05, respectively), as was rate-pressure product at 1.5 mm ST-segment depression (228 +/- 40 vs 199 +/- 38 b/min.mmHg.10(2), p < 0.01 and 253 +/- 42 vs 230 +/- 36 b/min.mmHg.10(2), p < 0.05, respectively). In conclusion, bamiphylline, at a dose able to increase ischemic threshold and exercise tolerance compared to placebo, does not prevent the warm-up phenomenon. These findings suggest that, in the setting of the warm-up phenomenon, A1 adenosine receptor blockade is insufficient to prevent ischemic preconditioning.

Effects of bamiphylline on exercise testing in patients with syndrome X.

An abnormal stimulation of adenosine A1-receptors has been suggested to play a role in the pathogenesis of both chest pain and ischemia-like electrocardiographic changes in patients with syndrome X and a nonselective adenosine antagonist (theophylline) has been reported to be beneficial in these patients. In this study we investigated the acute effects of bamiphylline, a specific A1-receptor antagonist, in 16 patients with syndrome X (14 women, age 57 +/- 6 years), with both angina and ST-segment depression inducible during exercise testing. All patients underwent two treadmill exercise tests (Bruce modified protocol) on 2 separate days, 5 minutes after the end of randomized intravenous infusion of either placebo (saline solution) or bamiphylline (300 mg). Severity of chest pain was assessed by a 100 mm visual analogic scale. There were no significant differences in resting heart rate and blood pressure after bamiphylline or placebo. Rate-pressure product (20 600 +/- 5000 vs 20 200 +/- 5200 bpm.mmHg), time to 1 mm ST depression (549 +/- 196 vs 581 +/- 201 sec), time to angina (519 +/- 209 vs 571 +/- 196 sec), and exercise duration (717 +/- 134 vs 676 +/- 166 sec) were also not significantly different after bamiphylline or placebo, but there was a mild reduction of the severity of exercise-induced chest pain (30 +/- 22 vs 39 +/- 20 mm, p < 0.05) with the active drug. Thus, in patients with syndrome X, bamiphylline does not improve exercise-induced ST changes, suggesting that A1-receptors are not significantly involved in their appearance. In addition, bamiphylline had little effect on anginal pain, suggesting that this cannot be mediated exclusively by A1-receptor stimulation in these patients.

17-alpha-Hydroxyprogesterone caproate and natural progesterone in assisted reproduction: a comparative study.

The use of luteal phase support has been demonstrated in patients undergoing an IVF/ET procedure. This study was designed to compare the absorption and the efficacy of two different luteal supports: 17-alpha-hydroxyprogesterone caproate (Lentogest, AMSA, Italy) and natural Progesterone (Prontogest, AMSA, Italy). A total of 80 patients received luteal supplementation with 50 mg of natural P/day intramuscularly, until beta-hCG evaluation. Then, in case of positive beta-hCG, patients were randomly divided into two groups (A and B) in order to compare two different protocols: Group A, 17-OHPc (341 mg once a week) and Group B, natural P (50 mg/day) both intramuscularly and extended for 10-12 weeks. Our study showed that the treatment with 17-OHPc results in a higher percentage of pregnancy rate compared to natural P, but the differences are not statistically significant. Thus, we emphasize that 17-OHPc preparation for better acceptance appears to be the most suitable and comfortable method for luteal phase support.

Intramuscular versus vaginal progesterone in assisted reproduction: a comparative study.

The effectiveness and the absorption of two progesterone (P) presentations have been compared for luteal phase support of patients aged < or = 37 years undergoing an in vitro fertilization (IVF) procedure for the first time, who were stimulated after pituitary desensitization with gonadotrophin releasing hormone agonists (GnRHa). All of them had two ovaries, normal ovarian functions and normal endometrial morphology: the indication for the assisted reproductive technique was the tubal factor. Two hundred and fifty patients were randomly allocated to two groups in order to compare two treatment protocols: Group A: natural i.m. P (50 mg/day, Prontogest, AMSA, Italy); Group B: micronized vaginal P (200 mg/day Esolut, Angelini, Italy). We were able to show that the i.m. P resulted in a higher percentage of pregnancies than the vaginal preparation, with statistically significant differences. We recommend the use of injectable P, and suggest reserving intravaginal P as a second choice for patients who cannot tolerate intramuscular administration.

Risk factors in patients with different clinical and angiographic manifestations of ischemic heart disease.

In patients who present with unheralded myocardial infarction both the severity and the extent of coronary atherosclerosis appear to be less than that in patients with chronic stable angina, thus suggesting that, in the latter, protective factors may prevent or delay the evolution towards acute coronary syndromes. Therefore, risk factors were compared in 88 consecutive patients (73 men; mean age 56 +/- 9 years) with unheralded myocardial infarction and a single, discrete, > 70% stenosis in the proximal right, left circumflex or left anterior descending coronary artery (Group 1) and in 55 consecutive patients (46 men; mean age 58 +/- 9 years with chronic stable angina and multiple, diffuse, > 70% stenoses localized both in the right and left coronary arteries (Group 2). Continuous data are presented as mean value +/- 1 SD, proportions as percentages. In Group 1 mean serum levels of total cholesterol, low-density lipoprotein cholesterol and triglycerides were similar to those in mg/dl, p = 0.93 and 160 +/- 87 vs 155 +/- 76, p = 0.74, respectively) while the mean serum level of high-density lipoprotein cholesterol was higher in Group 2 (49 +/- 4 vs 46 +/- 4 mg/dl, p = 0.005). The prevalence of a positive family history of ischemic heart disease, hypertension and smoking habit were similar in the two groups, while the prevalence of diabetes mellitus was higher in Group 2 (29 vs 6%, p = 0.001). Thus, in patients with otherwise similar coronary risk factors, higher levels of high-density lipoprotein cholesterol and diabetes mellitus appear to be associated with a reduced tendency of coronary atherosclerosis to cause acute coronary syndromes.

Fucosterol epoxide lyase of insects: synthesis of labeled substrates and development of a partition assay.

Fucosterol epoxide labeled with tritium in the C-29 methyl has been synthesized and employed in the development of a partition assay which allows the rapid determination of fucosterol epoxide lyase activity in vitro in homogenates of insect tissues. An independent synthesis of [24-14C]fucosterol epoxide provided a control substrate to evaluate nondealkylative transfer of labeled steroid to the aqueous layer during the enzyme assay. The diastereomeric 24R,28R- and 24S,28S-[29-3H]fucosterol epoxides were obtained via HPLC separation of their benzoate esters. Homogenates of the midgut tissue of larval tobacco hornworms (Manduca sexta) were examined at pH 5 to 9 in several buffer systems, and at temperatures of 7 to 67 degrees C in phosphate buffer. Optimal activity was found using pH 7.4, 76 mM phosphate buffer at 37 degrees C. The 24R,28R diastereomer of fucosterol epoxide was metabolized at a rate at least 100 times that of the 24S,28S isomer by this enzyme system.