LIVER-part 1 Dr. Saad M Attash 2018
تسلسل 9 المرحلة الرابعة جراحة د.سعد العدد6 5\3\2018Surgical anatomyThe liver is the largest organ in the body, weighing 1200-1800gThe liver parenchyma is entirely covered by a thin capsule and by visceral peritoneum in all but the posterior surface of the liver, termed the ‘bare area’ The liver is fixed in the right upper quadrant by peritoneal reflections which form ligaments.
Blood supply & venous drainage :The blood supply to the liver is unique, being derived 80 per cent from the portal vein and 20 per cent from the hepatic artery- hepatic A from coeliac trunk- portal vein formed by union of SMV &splenic V.- Three hepatic V drains into IVC Lymphatic drainage: LN at porta-hepatis – coeliac LN– some--- thoracic duct.
Functions : 1- formation & secretion of bile. 2- CHO, protein & fat metabolism. 3- metabolism of many drugs & hormones . 4- removal of ammonia. 5- liver is the storage house of glycogen, vit.B12, vit.A, iron & copper. 6- reticuloendothelial cells clear the blood from bacteria that can escape from the intestine to the portal circulation.
INVESTIGATIONSA– Liver function tests: 1- total serum bilirubin. Direct & indirect.2- AST serum aspartate aminotransferase.3- ALT serum alanine aminotransferase.4- alkaline phosphotase.5- serum albumin.6- prothrombin time.B–Imaging of liver: US- CT- MRI- arteriography C– Liver biopsy: per cutaneous –laparoscopy- laparotomy.
Liver trauma - 2nd common solid organ after spleen. - associated injury: ribs, pleura, lung, colon & spleen. Aetiology: 1- accidental trauma: blunt (RTA) & penetrating (bullet, stab). 2- iatrogenic injury: percut biopsy , PTC. 3- spontaneous rupture (eclampsia, hepatic tumour). Types of injury: 1- small subcapsular hematoma. 2- small superficial tear or tears. 3- large subcapsular or intrahepatic hematoma. 4- large deep tear or tears. 5- shattered liver. 6- vascular injury : most difficult hepatic V .
Clinical features & diagnosis: 1- history of trauma. 2- abdominal pain. 3- abdominal tenderness & rigidity. 4- lower rib fractures. 5- massive bleeding--- hemorrhagic shock. 6- minor bleeding---DPL , US, CT. 7- during laparotomy.
Treatment: 1- minor hemorrhage & small tear can be conservatively followed by regular CT or US. 2- continuous bleeding calls for surgical interference. 3- serious liver injuries require urgent laparotomy.
Complications Intrahepatic hematoma Liver abscess Bile collection Billiary fistula Hepatic artery aneurysm Arteriovenous fistula Arteriobilliary fistula Liver failure
Infections of the liver 1-viral hepatitis. 2-pyogenic liver abscess. 3-Amoebic liver abscess. 4-hydatid disease of the liver. 5-hepatic schistosomiasis.
Pyogenic liver absecss:Aetiology :A-- Sources of infection:1-biliary tract: commonest-ascending cholangitis caused by bile duct obstruction---- multiple liver abscesses. E.coli.2-portal vein: suppurative appendicitis & colon diverticulitis----(portal pyaemia) --- multiple liver abscesses. streptococci & anaerobes.3-arterial system(hematogenous): bacterial endocarditis, tonsilitis, osteomyelitis. staph-aureus.4-idiopathathic.B– Predisposing factors:1-immunocompromized patient.2-an already existing liver lesion as hydatid cyst, amoebic abscess, or hematoma.
Complications: Direct extension of abscess to the pleura, lung, pericardium, or peritonium. Clinical features: the usual symptoms include fever & its constitutioinal manifestations ,toxaemia, with RT hypochondrial or lower chest pain. - abdominal examination: tender hepatomegaly. - sometimes the symptoms of causative lesion e.g Charcot`s triad of cholangitis or the pain of appendicitis.
Investigations: 1- the usual laboratory disturbances include: -leucocytosiss. -anaemia & high ESR. -low serum albumin. -high alkaline phosphotase & transaminases level. -elevated serum bilirubin in case of cholangitis. 2- imaging US or CT.
Treatment As for any abscess the treatment is drainage of pus. - percutaneous guided drainage of pus. US or CT guided. The standard method open surgical drainage that allows dealing with any intra-abdominal cause. Tube drain+ antibiotic according to c/s.
Amoebic hepatitis & abscess Commoner than pyogenic abscess in the developing countries. (low hygiene + high humidity) ----tropical & subtropical regions. Aetiology : Entamoeba histolytica- the condition is a complication of amoebic colitis.
Pathology : - the trophozoites invade portal blood from colon, & migrate up to reside in the liver. - RT lobe of liver > LT. Amoebic colitis affects mainly the RT colon. - the parasite start a process of liquefactive necrosis ---infection---abscess that is usually single & unilocular. - pus is usually sterile with a brown chocolate color. The abscess has a shaggy wall that harbours the amoeba.
Complications - secondary bacterial infection. - rupture into the pleura , pericardium, or peritonium. Clinical features: -- SYMPTOMS: - upper abdominal pain. - low grade fever. - anorexia , nausea & weight loss. - a clear history of dysentery is not always obtained. -- SIGNS: - pale + toxic-----earthy look. - tender hepatomegaly. - tendeness in the RT lower intercostal spaces. - chest examination may reveal RT basal lung abscess or RT pleural effusion.
Differential diagnosis: 1- pyogenic liver abscess. 2- hepatocellular carcinoma. Investigations: 1- positive stool analysis & serological tests. 2- blood picture: leucocytosis & anaemia. 3- US or CT. 4- Therapeutic test of metronidazole treatment--- improvement in the general & local conditions after 3 days.
Treatment 1- conservative treatment is highly successful. Metronidazole 800mg 3 times daily for 7-10 days.2- US –guided percutaneous aspiration: for large abscess & if no response to treatment within 72 hours.3- open drainage Indications :- presence of secondary infection.- if the abscess is pointing.- if aspiration is difficult because of multilocular abscess or presence of thick pus.