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Biomedical subjects

A Pietrabissa

Publications and source records attributed to A Pietrabissa.

At least 73 records · Page 4Linked to original sources
PubMed1994

Intraoperative cholangiography during laparoscopic cholecystectomy. Routine vs selective policy.

An audit of routine intraoperative cholangiography in a consecutive series of 496 patients undergoing laparoscopic cholecystectomy has been performed. Cannulation of the cystic duct was possible in 483 patients (97%). The use of portable, digitized C-arm fluorocholangiography was vastly superior to the employment of a mobile x-ray machine and static films in terms of reduced time to carry out the procedure and total abolition of unsatisfactory radiological exposure of the biliary tract. Repeat of the procedure was necessary in 22% of cases when the mobile x-ray equipment was used. Aside from the detection of unsuspected stones in 18 patients (3.9%), routine intraoperative cholangiography identified four patients (0.8%) whose management would undoubtedly have been disadvantaged if intraoperative cholangiography had not been performed.

Bile Ducts↗
PubMed1994

Three-dimensional versus two-dimensional video system for the trained endoscopic surgeon and the beginner.

Because of the lack of depth perception in current two-dimensional endoscopic video systems, the performance of fine motor movements is impaired. Endoscopic surgeons are generally able to cope with this limitation, and the performance of complex procedures becomes easy with experience. To assess the value of three-dimensional vision, two groups of surgeons, with and without experience in endoscopic surgery, underwent dexterity tests at a simulator. Data from use of two- and three-dimensional video systems were analysed and are discussed in this paper. The three-dimensional system improved the ability to perform endoscopic procedures, particularly when the highest degree of hand-eye coordination was needed. A common sensation of ocular fatigue, related to the prolonged use of this equipment, may limit its usefulness in advanced endoscopic procedures.

Clinical Competence↗
PubMed1993

Localization of insulinoma by laparoscopic infragastric inspection of the pancreas and contact ultrasonography.

A new technique for localizing pancreatic insulinoma is described. This consists of a laparoscopic examination of the body and tail of the pancreas through an infragastric approach combined with contact ultrasonography of the gland. Accurate localization of an occult insulinoma in the body of the pancreas was achieved in one patient with the technique described. Laparoscopic contact ultrasonography of the pancreas by the infragastric approach should be as reliable as open intraoperative ultrasonography and constitutes the first step in the laparoscopic treatment of insulinoma.

Female↗
PubMed1993

Conjugation of benzoic acid with glycine in human liver and kidney: a study on the interindividual variability.

1. The rate of conjugation of benzoic acid with glycine was measured in the homogenates of 110 specimens of human liver and in 67 specimens of human renal cortex. 2. The assay for the formation of benzoyl glycine consisted of measuring the formation of benzoyl glycine from (14C) benzoic acid and glycine in the presence of coenzyme A and ATP. 3. In human liver, the mean (+/- SD) and coefficient of variation for the formation rate of benzoyl glycine were 254 +/- 90.5 nmol min-1 per g liver and 36%, respectively. There was a weak, but significant, negative correlation (r = -0.339, p < 0.001) between the rate of formation of benzoyl glycine and the liver donor's age. 4. In the human kidney, the rate of benzoyl glycine formation was normally distributed. The mean (+/- SD) and coefficient of variation were 321 +/- 99.3 nmol min-1 per g kidney and 31%, respectively. 5. These in vitro results are consistent with the view that the in vivo rate of conjugation of carboxylic acid with glycine varies among subjects and is normally distributed.

Adult↗
PubMed1992

Effect of kidney transplantation on quality of life measures.

Assessing the quality of life should be an essential part of the long-term results of surgery, particularly for those procedures that may influence a patient's lifestyle and body image. Eliminating the need for dependence on chronic hemodialysis, kidney transplantation improves the patient's autonomy but exposes them to the side-effects of immunosuppression and the constant threat of rejection. The purpose of this study was to compare the quality of life of patients on the waiting list for a kidney transplantation to that of those already transplanted at our Center to quantify carefully the impact of this therapy on the patient's physical, emotional, and social well-being. Computer analysis of the data collected from self-administered questionnaires revealed that the vast majority of successfully transplanted patients experience a significant improvement in almost all the areas investigated compared with the pretransplant group. In addition, we tried to use the questionnaire to predict which type of patient will adjust more fully to the impact of a kidney transplantation and which will probably need posttransplant psychological care and social support. Aside from clinical factors such as the time spent on hemodialysis before transplantation, the gender, the age, as well as the source of the organ (living vs. cadaver donor) seem to play a role in the final outcome of a successful kidney transplantation.

Adolescent↗
PubMed1991

Hepatic oxygen and lactate extraction during stagnant hypoxia.

As O2 delivery falls, tissues must extract increasing amounts of O2 from blood to maintain a normal O2 consumption. Below a critical delivery threshold, increases in O2 extraction cannot compensate for the falling delivery, and O2 uptake falls in a supply-dependent fashion. Numerous studies have identified a critical delivery in whole animals, but the regional contributions to the critical O2 delivery are less fully understood. In the present study, we explored the limits of O2 extraction in the isolated liver, seeking to determine 1) the normal relationship between O2 consumption and delivery in the liver and 2) the relationship of hepatic lactate extraction to the drop in hepatic O2 consumption at low O2 deliveries. To answer these questions, using support dogs as a source for oxygenated metabolically stable blood, we studied eight pump-perfused canine livers. By lowering the blood flow in a model of stagnant hypoxia, we explored the relationship between O2 consumption and delivery over the entire physiological range of O2 delivery. The critical O2 delivery was 28 +/- 5 (SD) ml.kg-1.min-1; the livers extracted 68 +/- 9% of the delivered O2 before reaching supply dependence. This suggests that the liver has an O2 extraction capacity quite similar to the body as a whole and not different from other tissues that have been isolated. At high blood flows, the livers extracted approximately 10% of the lactate delivered by the blood, but the arteriovenous lactate differences were small. At low blood flows, however, the livers changed from lactate consumption to production. The O2 delivery coinciding with the dropoff in lactate extraction did not differ significantly from the critical O2 delivery. We conclude that reductions in lactate uptake by the liver do not precede the transition to O2 supply dependence.

Animals↗
PubMed1990

Segmental liver transplantation from living donors. Report of the technique and preliminary results in dogs.

A technique of orthotopic liver transplantation using a segmental graft from living donors was developed in the dog. Male mongrel dogs weighing 25-30 kg were used as donors and 10-15 kg as recipients. The donor operation consists of harvesting the left lobe of the liver (left medial and left lateral segments) with the left branches of the portal vein, hepatic artery and bile duct, and the left hepatic vein. The grafts are perfused in situ through the left protal branch to prevent warm ischemia. The recipient operation consists of two phases: total hepatectomy with preservation of the inferior vena cava using total vascular exclusion of the liver and veno-venous bypass, implantation of the graft in the orthotopic position with anastomosis of the left hepatic vein to the inferior vena cava and portal, arterial and biliary reconstruction. Preliminary experiments consisted of four autologous left lobe transplants and nine non survival allogenic left lobe transplants. Ten survival experiments were conducted. There were no intraoperative deaths in the donors and none required transfusions. One donor died of sepsis, but all the other donor dogs survived without complication. Among the 10 grafts harvested, one was not used because of insufficient bile duct and artery. Two recipients died intraoperatively of air embolus and cardiac arrest at the time of reperfusion. Three dogs survived, two for 24 hours and one for 48 hours. They were awake and alert a few hours after surgery, but eventually died of pulmonary edema in 2 cases and of an unknown reason in the other. Four dogs died 2-12 hours postoperatively as a result of hemorrhage for the graft's transected surface. An outflow block after reperfusion was deemed to be the cause of hemorrhage in these cases. On histologic examination of the grafts, there were no signs of ischemic necrosis or preservation damage. This study demonstrates the technical feasibility of living hepatic allograft donation. It shows that it is possible, in the dog, to safely harvest non ischemic segmental grafts with adequate pedicles without altering the vascularization and the biliary drainage of the remaining liver. We propose that this technique is applicable to human anatomy.

Animals↗
PubMed1990

[Orthotopic liver transplantation and living donors. An experimental study in the dog].

Orthotopic liver transplantation (OLT) using partial grafts harvested from living donors would represent a further alternative to the limited supply of hepatic grafts, especially in pediatrics. We report herein the results of an original technique of living donor OLT that we have developed in the dog. This study was conducted in male mongrel dogs weighing 25-30 kg for the donors and 10-15 kg for the recipients. The donor operation consisted in harvesting the left lobe of the liver as a graft. The recipient operation consisted in the implantation of the graft in the orthotopic position after total hepatectomy with preservation of the inferior vena cava. Ten survival experiments were undertaken. The first donor died of infected liver necrosis of the quadrate lobe. All other donors survived without major complication. Among the 10 grafts, only 9 were used. Substantial survival could be obtained in 3 dogs. On recipient survived for 48 hours and 2 for 24 hours but their graft was functioning and producing bile. Two dogs died intraoperatively. The 4 other recipients developed an outflow block of the graft after reperfusion leading to lethal hemorrhage from the transected surface. This work is, to our knowledge, the first experimental study of OLT using living donors. It provides a technical basis to the clinical use of living hepatic allograft donors which otherwise depends on ethical issues.

Animals↗
PubMed1990

Bullet emboli to the systemic and venous circulation.

The rarity of bullet emboli leads to frequent delays in diagnosis and inadequate early management. Our recent experience with this entity is described, and 153 cases reported in the English-language literature are reviewed and summarized. The majority of cases occurs as a consequence of civilian violence among men in their 20s and 30s. Most bullet emboli follow the direction of blood flow, although 15% of venous bullets cause embolization in a retrograde manner. One in 10 arterial emboli follow a right-heart or venous injury. Arterial bullets are symptomatic in 80% of cases, venous bullets in only one third. The choice of surgical management must be individualized according to the symptoms caused by the bullet and its location in the vascular system. In general, arterial bullet emboli are removed because of symptoms or findings of acute peripheral ischemia. Arterial and venous emboli not causing symptoms should be removed according to the risk of possible displacement and further embolization. Selective intraoperative angiograms and phlebograms can precisely localize the migrating bullet and permit appropriate placement of incisions before removal.

Adult↗
PubMed1989

Experience with 647 consecutive tumors of the duodenum, ampulla, head of the pancreas, and distal common bile duct.

Between 1946 and 1987, 647 patients with periampullary tumors were diagnosed at the University of Chicago Medical Center. These included 549 tumors located in the head of the pancreas, 40 in the distal common bile duct, 29 in the duodenum, and 29 at the ampulla of Vater. Ninety-eight per cent of all tumors were adenocarcinoma, with 93% of the remaining being duodenal carcinoid or sarcoma. Operability rate ranged from 81% to 97%, according to the tumor location and histologic type. A combination of laparotomy, biopsy, and bypass was performed in 433 patients and only one survived 5 years (0.2%). Resectability rate ranged from 16.5% for pancreatic adenocarcinoma to 89.3% for ampullary tumors. Of the 133 resections, 80 were pancreatoduodenectomies, 29 total pancreatectomies, 7 duodenectomies, 2 gastrectomies, 8 common bile duct resections, and 7 local excisions. Overall 19% of patients who underwent radical resection died in the immediate postoperative period, although mortality has decreased to 5% since 1981. Mortality was 20% after a standard pancreatoduodenectomy and 24.1% after a total pancreatectomy. Five-year actuarial survival rates, including perioperative deaths, were 8.8%, 20%, and 32% for pancreatic, duodenal, and ampullary adenocarcinoma, respectively. One half of patients with sarcoma and two-thirds with carcinoid of the duodenum survived 5 years. No patient with distal common bile duct adenocarcinoma achieved a 5-year survival rate. Multivariate analysis on all patients operated on (n = 566) revealed that the 5-year survival rate was significantly related to intent of operation (palliative 0.2%, curative 12%; p less than 0.001), histologic type (adenocarcinoma 2%, carcinoid and sarcoma 31%; p less than 0.0001), and site (ampullary and duodenal 21%, biliary and pancreatic 0.9%; p less than 0.001). A second multivariate analysis, evaluating only those patients with adenocarcinoma who survived the perioperative period of the radical resection (n = 97) analyzed the influence of tumor size and differentiation, lymphatic, capillary, and perineural microinvasion, lymph node status, and type of procedure (pancreatoduodenectomy vs. total pancreatectomy) on 5-year survival. None of these additional variables was significantly associated with long-term survival rates. In addition we evaluated the presence of local or distant recurrence after resection by analyzing the findings from all autopsies performed on these patients (n = 49): 29.4% of patients died with local recurrence alone, 23.5% with distant recurrence alone, and 47.1% had both local and distant recurrences.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenocarcinoma↗
PubMed1988

Acute effects of peritoneovenous shunt (Le Veen) on the hemodynamics and gas exchange in patients with hepatic intractable ascites.

The acute effects of the peritoneovenous shunt (LeVeen) on hemodynamics and pulmonary gas exchange in 6 consecutive patients with intractable ascites and cirrhosis were evaluated. After opening the peritoneovenous shunt, there was a marked increase in cardiac index, (from 3.78 +/- 0.4 to 5.86 +/- 0.4 1/min. m2, p less than 0.01), and mean pulmonary artery pressure (from 17.3 +/- 1.9 to 23.3 +/- 1.5 mmHg, p less than 0.05), while a significant decrease in systemic vascular resistances (from 1086 +/- 116 to 694 +/- 52 dynes.sec.cm-5, p less than 0.05) was observed. In all patients there was a drop in arterial oxygen tension (PaO2) (from 76 +/- 3 to 67 +/- 3 torr, p less than 0.01) and an increase in venous admixture (Qsp/Qt) from 13.1 +/- 2 to 18.9 +/- 2%, p less than 0.01). The comparable increase in cardiac output and in venous admixture produced by opening the peritoneovenous shunt, might be related to the massive transfusion of ascitic fluid into the intravascular compartment. It is therefore concluded that this impairment of tas exchange further support discarding an appropriate amount of ascitic fluid at the time of shunt insertion.

Aged↗