PubMed Health⌕ Search

Biomedical subjects

Marcel Autran C Machado

Publications and source records attributed to Marcel Autran C Machado.

At least 19 recordsLinked to original sources

Silkclasy: a simple way for liver transection during anatomic hepatectomies.

BACKGROUND: Parenchymal transection is the most important step of liver resection, and during this phase, blood loss may lead to morbidity and mortality. Liver parenchyma can be transected by different ways such as finger fracture, clamp crushing, or instrument-based techniques. METHODS: A simple and cost-efficient method has been developed for liver transection using a technique based on silk crushing of the liver substance. RESULTS: We have successfully employed this technique in 278 consecutive liver resections from July 2001 to March 2006. The average duration of hepatic transection varied according to the type of liver resection: 22 min (range 15-42), 19 min (range 11-37), and 12 min (range 7-21) for right hepatectomy, left hepatectomy, and bisegmentectomy 2-3, respectively. The mean transection speed was 6.9 +/- 2.3 cm(2)/min. Blood transfusions were necessary in 42 patients (15.1%), and there were three operative deaths (1.1%). Morbidity rate was 20.9% (58 patients). CONCLUSIONS: This technique allows a safe and quick liver transection without the use of expensive hemostatic devices, and also precludes the use of inflow occlusion maneuvers. We recommend the use of this technique in centers with low economic resources.

Adolescent↗

Selected patients with metastatic melanoma may benefit from liver resection.

BACKGROUND: In the last few years there has been expanding use of hepatic resection for non-colorectal metastases. The purpose of this study is to evaluate the experience of liver resection for patients with metastatic melanoma. METHODS: Eighteen patients with metastatic melanoma were explored for possible surgical resection. All patients fitted the following criteria: absence of extra-hepatic disease after evaluation with CT/MRI and FDG-PET scans; disease-free interval longer than 24 months after the resection of the primary melanoma; presumed completely resectable lesions; absence of clinical co-morbidities. RESULTS: Liver resection was performed in 10 patients; 8 out of 18 presented with irresectable tumors and/or peritoneal metastases and were not operated. One patient presented with postoperative biliary fistula and was conservatively managed. No other complications or postoperative mortality were observed. After a mean follow-up of 25.4 months, 5 patients are alive and without evidence of recurrence. Overall median survival was 22 months; overall survival and disease-free survival were 70% and 50% respectively. CONCLUSIONS: Resection of liver metastases from melanoma in a selected group of patients may increase survival. Exploratory laparoscopy should be included in the preoperative armamentarium of diagnostic tools.

Adult↗

Hypertonic saline solution increases cerebral perfusion pressure during clinical orthotopic liver transplantation for fulminant hepatic failure: preliminary results.

UNLABELLED: During orthotopic liver transplantation for fulminant hepatic failure, some patients may develop sudden deterioration of cerebral perfusion and oxygenation, mainly due to increased intracranial pressure and hypotension, which are likely responsible for postoperative neurological morbidity and mortality. In the present study, we hypothesized that the favorable effects of hypertonic saline solution (NaCl 7.5%, 4 mL/kg) infusion on both systemic and cerebral hemodynamics, demonstrated in laboratory and clinical settings of intracranial hypertension and hemorrhagic shock resuscitation, may attenuate the decrease in cerebral perfusion pressure that often occurs during orthotopic liver transplantation for fulminant hepatic failure. METHODS: 10 patients with fulminant hepatic failure in grade IV encephalopathy undergoing orthotopic liver transplantation with intracranial pressure monitoring were included in this study. The effect on cerebral and systemic hemodynamics in 3 patients who received hypertonic saline solution during anhepatic phase (HSS group) was examined, comparing their data with historical controls obtained from surgical procedure recordings in 7 patients (Control group). The maximal intracranial pressure and the corresponding mean arterial pressure values were collected in 4 time periods: (T1) the last 10 min of the dissection phase, (T2) the first 10 minutes at the beginning of anhepatic phase, (T3) at the end of the anhepatic phase, and (T4) the first 5 minutes after graft reperfusion. RESULTS: Immediately after hypertonic saline solution infusion, intracranial pressure decreased 50.4%. During the first 5 min of reperfusion, the intracranial pressure remained stable in the HSS group, and all these patients presented an intracranial pressure lower than 20 mm Hg, while in the Control group, the intracranial pressure increased 46.5% (P < 0.001). The HSS group was the most hemodynamically stable; the mean arterial pressure during the first 5 min of reperfusion increased 21.1% in the HSS group and decreased 11.1% in the Control group (P < 0.001). During the first 5 min of reperfusion, cerebral perfusion pressure increased 28.3% in the HSS group while in the Control group the cerebral perfusion pressure decreased 28.5% (P < 0.001). Serum sodium at the end of the anhepatic phase and 3 hours after reperfusion was significantly higher in the HSS group (153.00 +/- 2.66 and 149.00 +/- 1.73 mEq/L) than in the Control group (143.71 +/- 3.30 and 142.43 +/- 1.72 mEq/L), P = 0.003 and P < 0.001 respectively. CONCLUSION: Hypertonic saline solution can be successfully used as an adjunct in the neuroprotective strategy during orthotopic liver transplantation for fulminant hepatic failure, reducing intracranial pressure while restoring arterial blood pressure, promoting sustained increase in the cerebral perfusion pressure.

Brain↗

Feasibility of bisegmentectomy 7-8 is independent of the presence of a large inferior right hepatic vein.

BACKGROUND: Right superior liver resection or bisegmentectomy 7-8 is defined as the anatomical removal of segments 7 and 8 of the liver. According to recent reports, this type of resection requires the presence of a large accessory right inferior hepatic vein to drain the remaining segment 6. However, anatomic studies have shown that segment 6 has multiple veins presenting several anastomosis with the surrounding hepatic veins. Therefore, the maintenance of the veins from segment 5 that ultimately drain into the middle hepatic vein can be enough to assure venous drainage of both segments. METHODS: Describe an alternative technique for bisegmentectomy 7-8 using intrahepatic glissonian access in patients with absence of a large inferior right hepatic vein. RESULTS: The technique was successfully performed in four consecutive patients without immediate or long-term venous or venous related complications. CONCLUSIONS: Bisegmentectomy 7-8 may increase resectability rate in patients with bilateral lesions and may also enhance the opportunity to perform repeated resections in cases of tumor recurrence. Our study confirms the anatomical assumption that bisegmentectomy 7-8 did not result in segmental outflow block even in the absence of a thick inferior right hepatic vein and therefore should be performed more often than reported so far. The absence of this vein should not be a straightforward indication for right hepatectomy in cases where a liver-sparing procedure such as bisegmentectomy 7-8 can be safely employed.

Anastomosis, Surgical↗

Liver resection as the definitive treatment for unilateral non-oriental primary intrahepatic lithiasis.

BACKGROUND: The current study sought to evaluate the results of liver resection as the treatment for unilateral non-oriental primary intrahepatic lithiasis (PHIL). METHODS: Twenty-seven symptomatic patients (mean age 42 years) were submitted to liver resection; the indications were parenchymal fibrosis/atrophy in 22 and biliary stenosis in 5. Resection was associated with a Roux-en-Y hepaticojejunostomy in patients with a significant degree of dilation of the extrahepatic biliary duct. RESULTS: There was no operative mortality and the morbidity rate was 7.4% (2 patients with biliary fistula). After a median follow-up of 41.2 months, the overall rate of good results was 92.6%. All patients submitted to liver resection alone presented good late results, while 80% of those with associated hepaticojejunostomy did not have complications (P = .12). Late complications were observed in 2 patients (7.4%): 1 with a liver abscess and 1 with cholangitis and recurrent stones. There was no mortality during long-term follow-up. CONCLUSIONS: Liver resection showed low incidence of complications and good long-term results. None of the patients with unilateral disease without associated extrahepatic bile duct dilation presented complications and they were considered cured. We believe that resection indications should be expanded and the procedure should be indicated as routine in patients with unilateral PHIL even in the absence of parenchymal fibrosis/atrophy or biliary stenosis.

Adult↗

Intrahepatic Glissonian access for segmental liver resection in cirrhotic patients.

The main goal of segmental technique is to preserve the maximum amount of liver parenchyma. Liver-preserving techniques are especially important for patients with hepatocellular carcinoma and cirrhosis. We report the technique for segmental liver resection in cirrhotic patients and detail technical difficulties and immediate surgical outcome. For right segmental liver resections the intrahepatic access is performed through small incisions around the hilar plate. Left segmental resection technique also consists of small incisions following specific anatomic landmarks. Nineteen cirrhotic patients underwent segmental liver resections. A blood transfusion was required in 2 patients. No patient experienced major bleeding from the liver incisions made for intrahepatic access. The median hospital stay was 5 days. No surgical mortality occurred. The intrahepatic access technique allows individual resections of liver segments and is feasible even in cirrhotic patients. Knowledge of segmental liver resection techniques is an essential armamentarium in the modern era of liver surgery.

Adult↗

Unusual case of pentastomiasis mimicking liver tumor.

Pentastomiasis is a rare zoonotic disease. Almost all recorded cases of human pentastomiasis had been incidental findings at autopsy. We report an unusual case of human pentastomiasis mimicking liver tumor successfully treated by liver resection. This clinical presentation is uncommon and it was probably caused by a pentastomid that exited its cyst and migrated to the liver causing an infarct that was mistaken as a primary liver tumor. Diagnosis could not be made before the surgery. This is the first reported case of human pentastomiasis in Brazil.

Animals↗

[Laparoscopic distal pancreatectomy for pancreatic cystadenomas].

BACKGROUND: Cystic neoplasms are an uncommon group among pancreatic tumors. These lesions are seen more frequently in recent surgical practice, probably because of advances in diagnostic and surgical techniques. Total tumor resection provides the best chance of cure and may remove the risk of malignant transformation of the cystadenomas, particularly of the mucinous type. Minimally invasive techniques have been revolutionary and provide clinical evidence of decreased morbidity and comparable efficacy to traditional, open surgery. However, laparoscopic pancreatic resection is not an established treatment for tumors of the pancreas. AIM: The authors present their initial experience with laparoscopic distal pancreatectomy for pancreatic cystadenomas. MATERIAL AND METHODS: Three female patients (mean age, 55 years) underwent laparoscopic pancreatic resection between September 2001 and December 2003. RESULTS: Laparoscopic pancreatic resection was successfully performed in all patients. Operative time varied between 4 and 6 hours. Intraoperative bleeding was minimal. Due to a thick pancreas, the application of vascular endoscopic stapler was difficult in one patient. Two patients presented postoperative pancreatic leakage with spontaneous resolution. CONCLUSIONS: Resection of the pancreas can be safely performed via the laparoscopic approach with all the potential benefits to the patients of minimally invasive surgery.

Aged↗

[Use of vascular stapling device in liver resections].

BACKGROUND: Among several liver resection techniques, the use of stapler in the portal pedicles is an interesting option. AIM: To describe the technique of liver resection using a vascular stapling device. PATIENTS AND METHODS: A total of eight patients underwent hepatic resections with stapling techniques. The authors have used intrahepatic approach glissonian pedicles with the application of a vascular stapler device in all cases. Liver parenchyma and hepatic veins were transected as usual. RESULTS: There were no deaths. No complications directly attributable to stapler ligations of portal pedicles were observed. CONCLUSION: Stapling techniques can be helpful in hepatic resection procedures. The vascular stapler may significantly reduce glissonian pedicle section time.

Adult↗

Non-Oriental primary intrahepatic lithiasis: experience with 48 cases.

An experience with the diagnosis and treatment of patients with non-Oriental primary intrahepatic lithiasis (PIHL) is described. A group of 48 native Brazilian patients with symptomatic PIHL were studied, and the patients' characteristics, diagnoses, treatment protocols based on the presentation of the disease, prognostic factors, and late results were analyzed. Liver resection was performed in patients with an irreversible lesion, such as parenchymal atrophy or biliary stenosis; and biliary drainage procedures were employed in patients with bilateral disease. Late results were considered good when no postoperative symptoms were observed and poor if there was pain recurrence or cholangitis. Overall good results were observed in 73.4% of the patients. Good late results were observed in 94.1% and 62.1% of the patients with unilateral and bilateral stones, respectively. None of the analyzed parameters (gender, age, previous biliary surgery, bilirubin level, serum leukocyte counts, prothrombin activity, previous history of cholangitis, stone location) predicted poor late results, but the risk for patients with bilateral stones to develop late complications was 7.2 times higher than for those with unilateral disease. Non-Oriental PIHL is a rare disease, and the patients' characteristics are similar to those of patients with Oriental PIHL. We believe that personalized treatment based on the presentation of the disease led to the high incidence of good late results in this series.

Adolescent↗

Anatomic left hepatic trisegmentectomy.

The technique of left trisegmentectomy was first published in 1982 and consists in the removal of the left liver (segments II, III, and IV) along with the right anterior sector (segments V and VIII). This procedure is based on the knowledge of the segmental liver anatomy. There are only a few technical reports describing this complex procedure. We describe an anatomic and standardized way to identify and isolate the glissonian sheaths of the left liver segments along with the portal pedicles from right anterior sector (segments V and VIII). The middle and left hepatic veins are dissected using Arantius ligament as landmark. With this technique, it is possible to achieve inflow and outflow control of the involved liver segments without hilar dissection or clamping. This technique provides a safe way to perform a left extended hepatectomy without warm ischemia of the relatively small remnant liver.

Clinical Competence↗

Hemihepatic ischemia for laparoscopic liver resection.

Laparoscopic hepatectomy has been recently proposed for the treatment of liver tumors. However, because of technical difficulties such as control of hemorrhage from the transection plane and large intrahepatic veins, laparoscopic hepatectomy has not been widely developed. The technique of hemihepatic ischemia has been used by the authors in conventional liver resection over the past 10 years with reduced splanchnic congestion and excellent hemostatic control. To minimize both intraoperative bleeding and circulatory and biochemical disturbances due to the interruption of blood flow to the liver, the authors describe a new technique combining hemihepatic ischemia and laparoscopic liver resection.

Blood Loss, Surgical↗

Portal vein resection: a modified technique for reconstruction after pancreaticoduodenectomy.

Pancreaticoduodenectomy is the only curative treatment for pancreatic head tumors. The possibility to achieve a potentially curative surgical treatment is limited to patients in which a complete tumor resection can be performed with free surgical margins. In a small number of patients with localized pancreatic cancer, negative margins are only accomplished with portal vein resection. Pancreaticoduodenectomy is often avoided in these patients due to the mistaken concept that venous resection may be followed by higher mortality and carries poorer survival. Actually, these patients present the same survival rate as patients similarly staged in whom portal vein resection was not performed. Therefore, venous resection is worthwhile. The authors describe an alternative technique for venous reconstruction after resection of a long segment of portal or superior mesenteric vein. The use of a venous graft as proposed in this study is feasible, easy to perform, and may simplify the venous reconstruction even in extensive mesentericoportal venous resection.

Humans↗

Anatomical resection of left liver segments.

HYPOTHESIS: Anatomical resection of the left liver segments are rarely mentioned in the literature. We describe an anatomical access to the left liver segments' pedicles without hilar dissection. DESIGN: Original surgical technique. PATIENTS AND METHODS: This technique was used in 26 consecutive resections involving left liver segments between July 2001 and December 2003. There were 15 men and 11 women with mean age of 57.1 years. Eleven patients had liver metastasis, 8 had primary liver cancer, 6 had benign lesions, and 1 had gallbladder cancer. The technique consists of small liver incisions according to anatomical landmarks such as the Arantius and round ligaments. In a systematized way, it was possible to reach every glissonian sheath of segments II, III, and IV. RESULTS: Liver resection was feasible using the proposed technique in every patient of this series, and the Pringle maneuver was not required in any patient. Intraoperative blood loss was minimal in all cases, and 23 patients did not require blood transfusion. There was no postoperative death. CONCLUSIONS: This operative procedure allows easy, fast access for anatomical resection of the left liver segments. It is useful for performing controlled hepatectomies without clamping the main hepatic pedicle and may facilitate the recognition of all left liver segment sheaths, with excellent immediate results.

Adult↗

A canine model of laparoscopic segmental liver resection.

Laparoscopic hepatectomy has been recently proposed for the treatment of liver tumors, however there is a lack of experimental models to study surgical technique and the metabolic reactions after this procedure. The dog is an important animal for research but the laparoscopic hepatectomy model is not well established in this animal. We describe the surgical laparoscopic technique of left liver segmentectomy in the dog and the preliminary results of this procedure. Female dogs weighting more then 15 kg were used. Four transversal abdominal incisions (two of 1 cm and two of 0.5 cm) were made for the introduction of the video camera and the other laparoscopic instruments. The liver was inspected and the left lobe was mobilized through incision of the left triangular hepatic ligament. The vascular pedicle corresponding to the left medial lobe (corresponding to segment II) was identified, dissected, and clamped, delimiting a correspondent ischemic area. The hepatic parenchyma was divided according to the previous delimitation with minimum bleeding. The segment of the liver was then removed through an enlarged abdominal incision. The incisions were closed by continuous suture. The mean time of the procedure was forty minutes. We observed normal clinical evolution without any sign of complications due to the hepatic resection, and normal augmentation of body weight on follow-up of more than 3 months. Left hepatectomy in the dog is a viable procedure and may serve for surgical training and development of research projects in this field.

Animals↗

Exposure of splenic hilum increases safety of laparoscopic splenectomy.

Laparoscopic splenectomy is becoming the gold standard technique for the treatment of hematological disorders of the spleen. Hemostasis is a fundamental step during laparoscopic splenectomy leading some authors to develop several techniques to control splenic vessels such as hand assistance, preoperative splenic artery embolization, and the use of vascular linear staplers. However, intraoperative bleeding is usually due to inadequate exposure of the hilar splenic vessels itself. The authors describe a standardized technique for the exposure of splenic pedicle using an endoscopic triangular retractor. We have been used this technique in 16 consecutive laparoscopic splenectomies with minimal blood loss. The present technique may increase the safety of laparoscopic splenectomy with adequate exposure of the splenic hilum reducing the conversion rate and intraoperative blood loss.

Adolescent↗

A standardized technique for right segmental liver resections.

HYPOTHESIS: The indications for segmental liver resections are increasing. This type of procedure can be performed by deep wedge transparenchymal transection or by the intrahepatic approach, reaching the portal pedicle through the hilar plate. We devised a systematized way to perform such an operation. DESIGN: Original surgical technique. PATIENTS AND METHODS: Fourteen consecutive patients (8 men and 6 women; mean age, 55 years) underwent right segmental liver resections between July 1, 2001, and July 31, 2002. Seven patients had liver metastasis, 3 had primary liver cancer, 3 had benign lesions, and 1 had gallbladder cancer. The surgery was performed by making 3 small incisions around the hilar plate. With a standardized method, the right posterior and anterior sheaths were reached by combining these incisions. RESULTS: Right segmental liver resection was feasible with the proposed technique in all patients. Intraoperative blood loss was minimal in all cases, and 11 patients did not require blood transfusion. There was no postoperative death. CONCLUSIONS: This operative procedure standardizes the intrahepatic approach to the right portal pedicle for right segmental resections. It may reduce bleeding at the site of hilar plate incisions and the need for main hepatic pedicle clamping and may facilitate the recognition of right posterior and anterior sheaths, with excellent immediate results.

Blood Loss, Surgical↗