Acute AbdomenDr R Prabakaran MS,MCh(SGE)

The term acute abdomen refers to signs and symptoms of abdominal pain and tenderness, a clinical presentation that often requires emergency surgical therapy

Most surgical diseases associated with an acute abdomen result from infection, obstruction, ischemia, or perforation.

NON SURGICAL CAUSES TO BE RULED OUT FIRST

Nonsurgical Causes of the Acute Abdomen

I Endocrine and Metabolic CausesUremiaDiabetic crisisAddisonian crisisAcute intermittent porphyriaHereditary Mediterranean fever

II Hematologic CausesSickle cell crisisAcute leukemiaOther blood dyscrasiasIII Toxins and DrugsLead poisoningOther heavy metal poisoningNarcotic withdrawalBlack widow spider poisoning

Although imaging studies have increased the accuracy with which the correct diagnosis can be made, the most important part of the evaluation remains a thorough history and careful physical examination. Laboratory and imaging studies are usually needed, but are directed by the findings on history and physical examination.

Surgical Acute Abdominal Conditions

HemorrhageSolid organ traumaLeaking or ruptured arterial aneurysmRuptured ectopic pregnancyBleeding gastrointestinal diverticulumArteriovenous malformation of gastrointestinal tractIntestinal ulcerationAortoduodenal fistula after aortic vascular graftHemorrhagic pancreatitisMallory-Weiss syndromeSpontaneous rupture of spleen

InfectionAppendicitisCholecystitisMeckels diverticulitisHepatic abscessDiverticular abscessPsoas abscess

PerforationPerforated gastrointestinal ulcerPerforated gastrointestinal cancerBoerhaaves syndromePerforated diverticulum

BlockageAdhesion induction small/large bowel obstructionSigmoid volvulusCecal volvulusIncarcerated herniasInflammatory bowel diseaseGastrointestinal malignancyIntussusception

IschemiaBuergers diseaseMesenteric thrombosis/embolismOvarian torsionIschemic colitisTesticular torsionStrangulated hernias

Visceral pain parietal painVague Sharp Poorly localisedExactly localiseddistension of hollow viscusIrritation of parietal peritoneum Epigastrium,umbilical region or suprapubic region(midline)Same side due to segmental innervation

Peritonitis Inflammation of peritoneum due to any causeInfection /sterile(pancreatitis)Primary /secondarySecondary most commonPrimary common in children(GRAM + pneumococcus and streptococcus)Primary in adults- cirrhosis and ascites-GRAM E.coli, Klebsiella

history Current imaging cannot replace history and clinical exam

onset, character, location, duration, radiation, and chronology of the pain documented

Pain identified with one finger is often more localized and typical of parietal innervation or peritoneal inflammation

indicating the area of discomfort with the palm of the hand is more typical of the visceral discomfort of bowel or solid organ disease

The history of progressive worsening inflammation associated with perforation

Intermittent colic (intestinal,biliary,ureteric)

Laboratory Studies for the Acute Abdomen

Hemoglobin levelWhite blood cell count with differentialElectrolyte, blood urea nitrogen, creatinine levelsUrinalysisUrine human chorionic gonadotropin levelAmylase, lipase levels

Total and direct bilirubin levelsAlkaline phosphatase levelSerum aminotransferaseSerum lactate levelsStool for ova and parasitesC. dificile culture and toxin assay

IMAGINGX-RAYUSGCT-REVOLUTIONISED DIAGNOSIS OF ACUTE ABDOMEN

X RAYCXR erect detects 1 ml of free air-upright AXR DECUBITUS- in critically ill-detects 5 ml of airX RAY detects pneumoperitoneum in 75% of hollow viscus perforation

calcifications in Xray5% of appendicolith10 % of gallstones90 % renal stones

Seen on Xray and helps in diagnosis

X-Ray abdomen supine and erect useful in intestinal obstruction60 % sensitivityColonic gas absent in small bowel obstruction(ominous sign)

USG abdomenMost sensitive- gallstones, GB wall thickening and pericholecystitic fluid collectionLimited in small bowel obstruction due to gasAccurate for free fluid

CT ABDOMENReadily available these days

Sonologist not available at night but CT technician available round the clock and the film can be interpreted by surgeons

Accurate for appendicitisDifferentiates paralytic ileus from mechanical causeIdentify transition pointBowel ischemia Blunt injury abdomen

Findings Associated With Surgical Disease in the Setting of Acute Abdominal Pain

Physical Examination and Laboratory FindingsAbdominal compartment pressures >30 mm HgWorsening distention after gastric decompressionInvoluntary guarding or rebound tendernessGastrointestinal hemorrhage requiring >4 U of blood without stabilizationUnexplained systemic sepsisSigns of hypoperfusion (e.g., acidosis, pain out of proportion to examination findings, increasing liver function test results)

Radiographic FindingsMassive dilation of intestineProgressive dilation of stationary loop of intestine (sentinel loop)PneumoperitoneumExtravasation of contrast from bowel lumenVascular occlusion on angiographyFat stranding, thickened bowel wall with systemic sepsis

Diagnostic Peritoneal Lavage (1000 mL)

>250 white blood cells/mL>300,000 red blood cells/mLBilirubin level higher than plasma level (bile leak)Particulate matter (stool)Creatinine level higher than plasma level (urine leak)