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P Parrilla

Publications and source records attributed to P Parrilla.

At least 55 records · Page 3Linked to original sources

Pathology findings in a model of auxiliary liver transplantation with portal vein arterialization in pigs.

OBJECTIVE: To determine the histological findings and temporal evolution that occur in auxiliary liver grafts as a consequence of arterialization of the portal vein (PVA). MATERIALS AND METHODS: We evaluated 10 auxiliary heterotopic liver transplants with arterialization of the PVA. The histological study was performed using an optical microscope to process liver samples with staining using hematoxylin and eosin. A biopsy of native liver tissue was used as a control. RESULTS: Two animals were excluded from the study, one due to ischemic necrosis of the graft and one that died 4 hours after transplant. All of the remaining eight animals underwent a histological study at 1 day, 7 days, and 14 days. The most significant histological findings were: (1) dilation of portal areas and sinusoids, which were detected at 24 hours and persisted; (2) thickening of the interlobular septum, which was observed after day 7 and progressively increased to day 14; (3) bile duct hyperplasia detected at the seventh day. CONCLUSIONS: The consistent, early findings in a pig liver with PVA included vascular dilation of the portal area and the sinusoids, with bile duct hyperplasia extending progressively and the thickening of interlobular connective tissue septa with a generalized perilobular connective tissue reaction, which did not seem to alter the internal structure of the lobule, which showed histologically normal hepatocytes. The fibrous reaction may be the first stage in chronic hepatopathy. Further long-term studies are required in this model.

Animals↗

Portopulmonary hypertension and liver transplantation: hemodynamic consequences at reperfusion.

BACKGROUND: The absence of portopulmonary hypertension (PH) upon preoperative evaluation for liver transplantation (OLT) does not exclude the occasional occurrence of an acquired PH while awaiting a graft. We sought to estimate hemodynamic changes and right ventriculoarterial coupling during reperfusion. METHODS: We studied 11 cirrhotic patients diagnosed with mild PH, according to the current classification: mean pulmonary artery pressure (MPAP)-25 to 34 mm Hg. These patients underwent OLT, using the piggyback technique (group PH). None of them had exhibited criteria for PH on preoperative echocardiography. This cohort was compared with 20 consecutive cirrhotic patients with normal MPAP at OLT. We performed a complete hemodynamic profile using a pulmonary artery catheter (RVEF, Baxter-Edwards, Calif, USA) before and 5 minutes after reperfusion. The variables were MPAP and right ventricular (RV) end-diastolic volume index (RVEDVI). Using standard formulas we calculated RV stroke work index (RVSWI), RV end-systolic elastance (Ees), pulmonary effective elastance (Ea), and RV-arterial coupling efficiency as the Ees/Ea ratio. Systolic ventricular function was expressed as RVSWI versus RVEDVI. RESULTS: During the anhepatic phase, MPAP, Ees, Ea, and RVSWI were higher in the PH group; but RVEDVI was lower. After reperfusion the pressure (MPAP), contractility (RVSWI) and preload (RVEDVI) increased in both groups. However, afterload (Ea) decreased in the non-PH group; accordingly, Es/Ea increased only in these patients. DISCUSSION: At reperfusion, the expansion in preload and cardiac output, without a similar afterload decrease, is responsible for the steady increase in pressure. Our results have shown that in the PH patient group, systolic ventricular function improves during reperfusion by a Frank-Starling mechanism; however, ventricular-arterial uncoupling is maintained (Ees/Ea < 1) because ventricular contractility is not appropriately balanced by simultaneous declines in afterload.

Hemodynamics↗

Effects of rapid paracentesis on right ventricular-arterial coupling in liver transplantation.

BACKGROUND: In cirrhotic patients intra-abdominal pressure (IAP) changes markedly modify splanchnic and systemic hemodynamics. Previous studies have evaluated the effects of increased IAP on steady-state cardiac performance, showing that right ventricular (RV) function becomes more depressed than that of the left ventricular. We sought to evaluate the effects of paracentesis on RV function and ventricular-arterial coupling among cirrhotics undergoing liver transplantation (OLT). METHODS: Twelve cirrhotic patients undergoing OLT underwent hemodynamic profiles before and 5 minutes after paracentesis, employing a right ventricular ejection fraction catheter in the pulmonary artery. We studied heart rate, systolic pulmonary artery pressure, central venous pressure (CVP), stroke volume index (SVI), RV end-diastolic volume index (RVEDI), and RV ejection fraction. In addition RV stroke work index (RVSWI), RV end-diastolic compliance (RVEDC), RV end-systolic elastance (Ees), pulmonary artery effective elastance (Ea), and RV coupling efficiency (Ees/Ea ratio) were calculated employing standard formulas. RESULTS: After removal of mean ascites volume of 5.6 +/- 2.2 L (range 4.0 to 8.04 L), SVI, RVEDI, RVSWI, and RVEDC were significantly increased and conversely CVP, Ees, and Ea were decreased with an ea/ea ratio unchanged. CONCLUSIONS: Before paracentesis Ees/Ea is preserved by increased of RV contractility; after paracentesis the coupling was maintained.

Ascites↗

Differential response of the systemic and pulmonary circulation related to disease severity of cirrhosis.

BACKGROUND: In cirrhotic patients, the degree of hepatic insufficiency has been related to a physiological landmark: arterial vasodilatation. We sought to assess how the severity of disease, which was stratified according to the Child-Pugh criteria, influences the pulmonary and systemic circulation among patients undergoing liver transplantation. METHODS: We studied 86 cirrhotic patients in three groups: grade A (n = 10), grade B (n = 54), and grade C (n = 22). The outurnes were classified based upon a complete hemodynamic profile obtained using a pulmonary artery catheter (RVEF, Baxter-Edwards, Calif, USA) after induction of anesthesia. The variables were mean arterial and pulmonary artery pressures and cardiac index (CI). Using standard formulae, afterload was calculated as elastance of systemic (Es) and pulmonary (Ep) arterial beds, expressed by the ratio of end-systolic pressure to stroke volume. The relation between pulmonary and systemic circulation was also evaluated by the ratio (Ep/Es). RESULTS: Es was significantly lower in each class than in previous one. Also, Ep was smaller in class B than in class C patients. In addition, CI was significantly higher with disease severity. CONCLUSION: We observed that the hyperdynamic circulation in cirrhosis is directly related to severity of disease. Nevertheless Ep/Es was progressively higher among each group; these data suggest that the hyperdynamic circulation is mainly due to circulatory alterations in the splanchnic area. We conclude that pulmonary vasodilatation is directly related to the severity of cirrhosis, although its evolution is independent of other vascular areas.

Blood Circulation↗

Attitudes toward xenotransplantation among nonhealth service workers in a hospital with a preclinical xenotransplantation program.

INTRODUCTION: Our hypothesis was that nonhealth workers (NHW) in our hospital should have a more favorable opinion toward xenotransplantation than the general population, given that this group is in closer contact with a preclinical xenotransplantation program. Therefore, our objective was to determine the attitude of NHW in a hospital with a preclinical liver xenotransplantation program and to determine the factors that influenced this attitude. MATERIALS AND METHODS: A random sample of 276 subjects in nonhealth services was used. For the distribution of the questionnaire, we contacted the head of each of the services and explained the project. They became responsible for the distribution and collection of the questionnaires in randomly selected work shifts. A random sample of 250 individuals from our community was used as a control group. RESULTS: As for animal organ donation for humans, if the results could be superimposed on those achieved by human donors, 63% would be in favor, 30% undecided, and the remaining 7% against. The attitude toward xenotransplantation was more favorable in the control group (74% versus 63%, P < .05). On analyzing the variables that influence attitudes toward xenotransplantation, we found that there is no significant relationship to the classical psychosocial variables (P > .05). However, there is a relationship to prior attitudes toward different types of human organ donation and the possibility of needing a transplant oneself. CONCLUSIONS: The attitudes toward xenotransplantation among NHW are not as favorable as in the general population.

Adult↗

Evaluation of CD86 gene polymorphism at +1057 position in liver transplant recipients.

BACKGROUND: Efficient T cell-APC interaction requires the participation of primary and co-stimulatory signals. The main co-stimulatory pathway involves the interaction of CD80 and CD86, expressed on the APCs, with their T cell counter-receptor, CD28 and CTLA-4. Recently, a G to A transition has been described at position +1057 of the CD86 gene, located in their cytoplasmic tail. METHODS: CD86 polymorphism was analyzed by sequence based typing in DNA samples obtained from 205 liver transplant recipients. Acute rejection and chronic rejection were diagnosed based upon conventional clinical, biochemical and histological criteria. RESULTS: The study of CD86 +1057 (G/A) polymorphism revealed that recipients bearing the A allele or the AA genotype have a reduced risk of acute rejection. In fact, the AA genotype was absent in the group of patients showing acute rejection episodes, whereas its frequency in those patients without acute rejection episodes was 8.8% (P=0.009, OR=0.07). This polymorphism did not reveal any association with the incidence of chronic rejection, but patients bearing the AA genotype showed a higher graft survival rate (83.3%) than those bearing the GA genotype (49.3%) or GG genotype (56.5%). CONCLUSIONS: The results of the present report suggest that the CD86 AA genotype at +1057 position could be involved in liver transplant acceptance, given that its presence is related to a decrease of acute rejection frequency and to a graft survival increase.

Acute Disease↗

Definitive treatment for persistent hypoparathyroidism in a kidney transplant patient: parathyroid allotransplantation.

Post-surgical hypocalcemia is usually a transitory complication in thyroid and parathyroid surgery that can be resolved quickly, although it becomes a delicate matter when the problem persists. Parathyroid transplantation is the choice of treatment; however, the associated immunosuppression can cause side effects. The following case study shows the transplantation of parathyroid tissue from a patient with secondary hyperparathyroidism to another kidney transplant patient with severe hypocalcemia that was medically intractable. The graft is functioning after 2 years.

Adult↗

[Multivariate study of the psychosocial factors affecting public attitude towards organ donation].

INTRODUCTION: Organ transplantation is a therapy which depends on society for its development. The objectives here are: 1) to understand the structure of public opinion towards organ donation in the population aged over 15 years of age in our Community; 2) to analyse the psychosocial variables which affect this opinion and 3) to define the population profiles on this matter. MATERIALS AND METHODS: Random sample (n = 2.000) stratified for age, sex and geographical location (error for 95.5%, e +/- 2.24) to whom we apply a questionnaire about the psychosocial aspects of organ donation. Descriptive statistics, Student's t-test, Chi-squared test and logistical regression analysis. RESULTS: 63% have a favourable attitude towards organ donation, of which 11% have a donor's card. A statistical association has been observed between favourable public opinion and different psychosocial variables (p < 0.05), with some independent variables persisting in the multivariate analysis such as age, level of education (OR = 1.78), information given by family members (OR = 1.62), health workers (OR = 2.01) and talks in educational centres (OR = 2.13); previous experience with donation and transplantation (OR = 2.02), knowledge of the concept of brain death (OR = 1.4); partner's favourable opinion towards donation (OR = 2.6), being a blood donor (OR = 3), taking part in prosocial activities (OR = 1.6) and attitude towards incineration of the cadaver after death (OR = 1.8). CONCLUSIONS: The profile of a person who is against donation is of a man or woman, > 50 years of age, with primary studies or below, with no previous experience of the matter, who does not understand the concept of brain death nor their partner's opinion towards donation, who has not found out any information about donation through specialised forums, with an unfavourable opinion towards blood donation or pro-social activities and who is fearful of manipulation of the cadaver after death.

Adolescent↗

Ineffective oesophageal motility does not affect the clinical outcome of open Nissen fundoplication.

BACKGROUND: Nissen fundoplication is considered the 'gold standard' in antireflux surgery but some surgeons employ a different surgical strategy when gastro-oesophageal reflux disease (GORD) is associated with motor disorders of the oesophageal body. METHODS: Ninety-three patients undergoing surgery for GORD were divided into two groups: 52 patients (group 1) had normal oesophageal body motility and 41 (group 2) had ineffective oesophageal motility (IOM). All patients had a short Nissen fundoplication via a laparotomy. The median follow-up was 5 years in group 1 and 6.5 years in group 2. RESULTS: The clinical outcome was satisfactory in more than 90 per cent of the patients in both groups. Only one of ten patients with IOM and dysphagia before operation still had dysphagia after surgery. One patient in each group developed postoperative dysphagia. Six of 52 patients with normal motility and eight of 41 with IOM had persistent pathological acid reflux after surgery. Significant increases in contractile wave pressure and a decrease in the percentage of non-propagated waves were found in group 2 after fundoplication. CONCLUSION: Patients with IOM did not have an increased rate of dysphagia after total fundoplication compared with those with normal motility, but they did have a higher rate of recurrence of endoscopic and pH-proven reflux.

Adolescent↗

Primitive leiomyosarcoma of the breast: case report and review of the literature.

Sarcomas of the breast account for under 1% of breast tumours. Leiomyosarcomas are less common, being a subgroup of sarcomas of the breast. Only 23 cases with immunohistochemical or electron microscopy confirmation are reported in the literature. The case of a 58-year-old woman with a leiomyosarcoma 4 cm in diameter in the upper external quadrant of the right breast is presented. Mammography and sonography were compatible with a fibroadenoma or phylloides tumour, and fine-needle aspiration (FNA) suggested medullary carcinoma. The patient underwent a Madden-type modified radical mastectomy and axillary lymphadenectomy. Adjuvant chemotherapy was implemented with Adriamycin (four cycles of 21 days). One year after surgery the patient is tumour free.

Breast Neoplasms↗

Risk factors for malignancy in multinodular goitres.

BACKGROUND: Multinodular goitre (MNG) is quite often associated with thyroid carcinoma, but the risk factors for malignancy are not well known. The aim is to analyse patients with thyroid carcinoma associated with MNG to determine the clinical risk factors for malignancy. METHOD: From a series of 672 MNGs we analysed a subgroup of 59 patients presenting with an associated thyroid carcinoma. The variables analysed were age, sex, family history, cervical radiation therapy, residence in areas of endemic goitre, prior thyroid surgery, time of evolution, asymptomatic status, hyperthyroidism, compressive syndromes, intrathoracic prolongation, goitre consistency and cervical adenopathies. These were compared to MNGs not developing malignancy using the Chi-squared test, Student's t test and a logistic regression test. RESULTS: Of the 59 cases, 37 corresponded to a microcarcinoma (< or =1 cm). The most common histological type was papillary (n=48), followed by follicular (n=6). In 20 cases the carcinoma was multifocal, and capsular involvement was noted in 16 patients, lymph node involvement in five and vascular involvement in another five. The multivariate analysis confirmed the following as independent variables associated with the presence of carcinoma: family history of thyroid pathology (RR=1.6), history of cervical radiation therapy (RR=1.8), recurrent goitre (RR=2.1) and presence of adenopathies on physical exploration (RR=1.6). CONCLUSION: The risk factors for carcinoma associated with MNG are family history of thyroid pathology, personal history of cervical radiation therapy, prior surgery and presence of cervical adenopathies.

Adenocarcinoma, Follicular↗

Influence of different sources of information on attitude toward organ donation: a factor analysis.

OBJECTIVES: To determine media through which the population receives information on donation; to analyze the association between the sources of information and the psychosocial variables with respect to the opinion on donation; and to determine how each source of information influences this opinion. MATERIALS AND METHODS: A questionnaire on donation was administered to a random sample of 2000 persons stratified by age, gender, and geographical location, of whom 1143 respondents claimed to have no experience with donation and/or transplantation. A statistical analysis was done between the sources of information or the psychosocial variables or their co-variation to determine their specific impact on the population. RESULTS: The medium with the greatest impact on the population is television; the second factor is the press and radio; the third is magazines and talks with friends/family; the fourth is hoardings and posters, and campaigns about organ donation; and the last factor is information given by health professionals. In the factor analysis between sources of information and psychosocial variables, an association was observed between press, radio, and information given by health professionals and a higher education level; and between information provided by discussions in schools, by age, and a higher level of education. Sources of Information sources as that have a favorable effect on donation include discussions, (P = .0079), and information by health professionals (P < .0005) and by friends (P = .0132) and by family (P = .0044). CONCLUSIONS: Opinion on donation is more favorable among subjects who have received information on an individual basis and at specialized meetings. The only psychosocial variable associated with some sources of information is the level of education.

Adolescent↗

Public attitude toward xenotransplantation: opinion survey.

BACKGROUND: Although xenotransplantation is still in an experimental phase, it is presented herein as a possible solution to the organ shortage. However, there are few data concerning how the general public would accept treatment with animal organs, especially after recent incidents of infections of animal origin, such as "avian influenza" or "SARS disease." The aim of this study was to determine the attitude of the general public toward xenotransplantation of organs. MATERIALS AND METHODS: Using an opinion survey, a study was performed on a random sample of 250 subjects in an urban setting. The questionnaire was administered by personnel from the regional transplant coordination center. Completion of the form was self-directed and anonymous for each respondent. The attitude toward donation of human and animal organs was evaluated by analyzing different psychosocial variables that may influence this attitude. A descriptive statistical study was performed using Student's t test and the chi-square test. RESULTS: Ninety-eight percent of respondents completed the survey (n=245). As for human donation, 60% are in favor of cadaveric donation with 21% are in favor of living donation, a rate that increases to 74% if it is for a living partner. As for animal donation, if the results were similar to those obtained with human organs, 74% (n=181) would accept an animal organ if they needed it, as opposed to 18% (n=45) who were undecided and 8% (n=19) against (P <.005). Analysis of variables that influence attitudes toward xenotransplantation showed that this attitude was more positive among those having had a previous experience with transplantation (P=.028) and those having a positive attitude toward cadaveric donation (P=.007). Factors traditionally related to cadaveric donation, such as manipulation of the body or pro-social activities, showed no influence. CONCLUSIONS: In the population studied, a positive attitude toward xenotransplantation was greater than toward cadaveric donation, assuming the results of these two types of transplants were comparable. Such an attitude is related to human donation, although it is not influenced by many traditional factors.

Animals↗

Cardiovascular changes during drainage of pericardial effusion by thoracoscopy.

BACKGROUND: Cardiovascular changes during drainage of pericardial effusion are not well understood, and most studies are of systemic effects and not of right ventricular performance. Thoracoscopy is not widely used to drain pericardial effusions because of haemodynamic changes in relation to the use of single lung ventilation. PATIENTS AND METHODS: We studied 16 patients undergoing partial pericardiectomy for pericardial effusion, using videothoracoscopy with a low-pressure pneumothorax (6 mm Hg). Cardiac output was measured by thermodilution with the patient anaesthetized in the supine position before the procedure; in the right lateral position after a low-pressure pneumothorax had been established; and after drainage of the pericardial effusion. RESULTS: Before the procedure, cardiac output was low and central venous pressure and pulmonary artery occlusion pressure were increased. Systemic vascular resistance and arterial blood pressure were within normal limits. Cardiac filling pressure and pulmonary arterial pressure increased during the pneumothorax. After the drainage cardiac index increased and systemic and pulmonary vascular resistances were reduced. CONCLUSIONS: Pericardial effusion reduces right ventricular distensibility, right and left systolic ventricular function, and cardiac output. Anaesthesia with mechanical ventilation and a low-pressure pneumothorax do not affect the circulation greatly. Drainage of the pericardial effusion allows cardiac distensibility to increase and cardiac performance changes to allow increased ejection.

Adolescent↗

Neoadjuvant radiation and chemotherapy in rectal cancer does not increase postoperative complications.

BACKGROUND AND AIMS: Neoadjuvant radiation and chemotherapy in rectal cancer reduces local recurrences and increases the rate of conservative sphincter surgery. However, an increase in postoperative morbidity and mortality has also been observed. This study analyzed the operative difficulty and postoperative complications in patients with this treatment. PATIENTS AND METHODS: Retrospective review of 103 patients with rectal cancer, divided into two groups: group A, 53 patients undergoing preoperative radiotherapy with 45 Gy combined with chemotherapy, and group B, 50 patients with rectal cancer who received surgery after diagnosis. Both groups were homogeneous. The two groups were compared for both technical difficulty, using intraoperative data and rate of complications. RESULTS: There were no statistically significant differences between the two groups with regard to intraoperative or postoperative data. In group A there were 20 complications in 17 patients (32%) and in group B 22 complications in 19 patients (38%). The rates of perineal wound infection were similar. The percentage of anastomotic leaks was higher in group A. A greater number of anterior resections was performed in group A. CONCLUSION: Preoperative radiation and chemotherapy in rectal cancer does not increase postoperative complications and increases the rate of sphincter-preserving surgery.

Adult↗

Psychosocial profile in favor of organ donation.

INTRODUCTION: The lack of organ donation continues to be a major limiting factor in transplantation. Our aims are: (1) to define the psychosocial profile against organ donation, and (2) to determine the impact of a law on the procurement and transplantation of organs based on "presumed consent" in the population. MATERIALS AND METHODS: The population in this study (n = 2000) was randomly selected and stratified according to sex, age, and geographic localization. The attitude toward organ donation and transplantation was evaluated according to a questionnaire that probed psychosocial aspects of donation. Statistical comparisons were performed using the chi2 and logistic regression tests. RESULTS: The population attitude toward organ donation was favorable in 63% of subjects, unfavorable in 31%, and 6% did not respond. With regard to the law based on "presumed consent," only 24% of the population agreed with the law; 53% thought it was an abuse of authority. The population subgroup with a negative attitude to the law was characterized by: age over 40 years, low educational level, no previous experience with organ donation or transplant, no experience in prosocial activities, a refusal to accept cadaver manipulation or mutilation, and lack of knowledge of the brain-death concept. CONCLUSIONS: The psychosocial profile against donation is a person above 40 years with a low level of education who has never performed prosocial activities, did not have previous experience with organ donation or transplantation, displays no knowledge of the brain-death concept, and rejects cadaver manipulation. For these people a law based on "presumed consent" is considered an abuse of authority.

Adolescent↗

Role of liver transplantation in the management of metastatic neuroendocrine tumors.

INTRODUCTION: In the majority of patients transplanted for unresectable liver metastases, long-term results are disappointing because of early tumor recurrence. Due to its biologically less aggressive nature, neuroendocrine metastases (NM) may represent a good indication for liver transplantation (LT). PATIENTS AND METHODS: Between January 1996 and May 2000, five patients with NM were transplanted. The primary tumors were located in the pancreas (n=4) and the small bowel (n=1). In three cases there were symptoms related to hormone production: two carcinoids, and one gastrinoma. The management of primary tumors was sequential in three patients with the tumor being resected before LT (one Whipple procedure and two left pancreatectomies). In two patients the resections of the primary tumors and the LT were simultaneous namely one bowel resection and one left pancreatectomy. All patients were treated with chemotherapy. RESULTS: Two patients developed recurrent disease succumbing at 15 months (nonfunctioning NE pancreatic head tumor) and 17 months (carcinoid of the pancreatic tail) post-LT. Another patient died at 3 months post-LT due to technical complications. The other two patients are alive and free of recurrence. CONCLUSION: Despite the promising results obtained with LT for NM, our experience indicates that patients must be carefully selected. Perhaps the use of more aggressive chemotherapeutic protocols combined with an individualized approach will improve the results.

Adult↗