Acute Abdomen

Overview

Definition

Acute abdomen is the constellation of signs and symptoms associated with severe abdominal pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways and peritonitis Peritonitis Inflammation of the peritoneum lining the abdominal cavity as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the peritoneal cavity via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the abdominal cavity itself through rupture or abscess of intra-abdominal organs. Penetrating Abdominal Injury that frequently requires emergency surgical intervention.

Epidemiology

• Abdominal pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways, in general, comprises 5%–10% of ED visits.
• About one-third of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship > 65 years old with abdominal pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways will require surgical intervention.
• Acute abdomen:
  • Young individuals: Appendicitis Appendicitis Appendicitis is the acute inflammation of the vermiform appendix and the most common abdominal surgical emergency globally. The condition has a lifetime risk of 8%. Characteristic features include periumbilical abdominal pain that migrates to the right lower quadrant, fever, anorexia, nausea, and vomiting. Appendicitis is the most common cause.
  • Older individuals with acute abdomen most commonly have:
    • Biliary disease
    • Bowel obstruction Bowel obstruction Any impairment, arrest, or reversal of the normal flow of intestinal contents toward the anal canal. Ascaris/Ascariasis
    • Intestinal ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage
    • Diverticulitis Diverticulitis Inflammation of a diverticulum or diverticula. Diverticular Disease

Etiology

Nonsurgical causes of acute abdomen:

• Endocrine/metabolic causes:
  • Acute intermittent porphyria Acute intermittent porphyria An autosomal dominant porphyria that is due to a deficiency of hydroxymethylbilane synthase in the liver, the third enzyme in the 8-enzyme biosynthetic pathway of heme. Clinical features are recurrent and life-threatening neurologic disturbances, abdominal pain, and elevated level of aminolevulinic acid and porphobilinogen in the urine. Porphyrias
  • Hereditary Mediterranean fever Mediterranean fever Brucellosis (also known as undulant fever, mediterranean fever, or malta fever) is a zoonotic infection that spreads predominantly through ingestion of unpasteurized dairy products or direct contact with infected animal products. Clinical manifestations include fever, arthralgias, malaise, lymphadenopathy, and hepatosplenomegaly. Brucella/Brucellosis
  • Uremia Uremia A clinical syndrome associated with the retention of renal waste products or uremic toxins in the blood. It is usually the result of renal insufficiency. Most uremic toxins are end products of protein or nitrogen catabolism, such as urea or creatinine. Severe uremia can lead to multiple organ dysfunctions with a constellation of symptoms. Acute Kidney Injury
  • Diabetic ketoacidosis Ketoacidosis A life-threatening complication of diabetes mellitus, primarily of type 1 diabetes mellitus with severe insulin deficiency and extreme hyperglycemia. It is characterized by ketosis; dehydration; and depressed consciousness leading to coma. Metabolic Acidosis
• Hematologic causes:
  • Sickle cell crisis
  • Acute leukemia
• Toxins and drugs:
  • Lead poisoning Lead poisoning Poisoning that results from chronic or acute ingestion, injection, inhalation, or skin absorption of lead or lead compounds. Metal Poisoning (Lead, Arsenic, Iron)
  • Narcotic withdrawal
  • Black widow spider Spider Arthropods of the class arachnida, order araneae. Except for mites and ticks, spiders constitute the largest order of arachnids, with approximately 37, 000 species having been described. The majority of spiders are harmless, although some species can be regarded as moderately harmful since their bites can lead to quite severe local symptoms. Spider Bites poisoning

Surgical causes of acute abdomen:

• Hemorrhage:
  • Trauma
  • Ruptured aneurysm Aneurysm An aneurysm is a bulging, weakened area of a blood vessel that causes an abnormal widening of its diameter > 1.5 times the size of the native vessel. Aneurysms occur more often in arteries than in veins and are at risk of dissection and rupture, which can be life-threatening. Thoracic Aortic Aneurysms
  • Hemorrhagic pancreatitis Pancreatitis Inflammation of the pancreas. Pancreatitis is classified as acute unless there are computed tomographic or endoscopic retrograde cholangiopancreatographic findings of chronic pancreatitis. The two most common forms of acute pancreatitis are alcoholic pancreatitis and gallstone pancreatitis. Acute Pancreatitis (usually does not require surgical intervention initially)
  • Mallory–Weiss tear
  • Ruptured ectopic pregnancy Ectopic pregnancy Ectopic pregnancy refers to the implantation of a fertilized egg (embryo) outside the uterine cavity. The main cause is disruption of the normal anatomy of the fallopian tube. Ectopic Pregnancy
• Infection:
  • Appendicitis Appendicitis Appendicitis is the acute inflammation of the vermiform appendix and the most common abdominal surgical emergency globally. The condition has a lifetime risk of 8%. Characteristic features include periumbilical abdominal pain that migrates to the right lower quadrant, fever, anorexia, nausea, and vomiting. Appendicitis
  • Diverticulitis Diverticulitis Inflammation of a diverticulum or diverticula. Diverticular Disease
  • Hepatic abscess Abscess Accumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection. Chronic Granulomatous Disease
  • Meckel diverticulitis Diverticulitis Inflammation of a diverticulum or diverticula. Diverticular Disease
• Perforation Perforation A pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force. Esophagitis:
  • Perforated gastric ulcer Gastric ulcer Ulceration of the gastric mucosa due to contact with gastric juice. It is often associated with Helicobacter pylori infection or consumption of nonsteroidal anti-inflammatory drugs (NSAIDS). Peptic Ulcer Disease
  • Perforated diverticulum Diverticulum A pouch or sac opening from the colon. Diverticular Disease
  • Perforated tumor Tumor Inflammation
  • Boerhaave syndrome Boerhaave Syndrome Esophageal Perforation
• Obstruction:
  • Small- or large-bowel obstruction due to adhesions or malignancy Malignancy Hemothorax
  • Volvulus Volvulus A volvulus is the twisting or axial rotation of a portion of the bowel around its mesentery. The most common site of volvulus in adults is the colon; most frequently the sigmoid volvulus. Patients typically present with symptoms of bowel obstruction such as abdominal pain, distension, vomiting, and constipation/obstipation. Volvulus
  • Incarcerated hernia Incarcerated Hernia Abdominal Hernias
  • Intussusception Intussusception Intussusception occurs when a part of the intestine (intussusceptum) telescopes into another part (intussuscipiens) of the intestine. The condition can cause obstruction and, if untreated, progress to bowel ischemia. Intussusception is most common in the pediatric population, but is occasionally encountered in adults. Intussusception
• Ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage:
  • Mesenteric thrombosis Thrombosis Formation and development of a thrombus or blood clot in the blood vessel. Epidemic Typhus or embolism
  • Ovarian torsion Ovarian torsion Ovarian torsion is a clinical emergency in which the ovaries (with or without the fallopian tubes) twist along their axis, leading to partial or complete obstruction of their blood supply. Ovarian torsion is also called adnexal or tubo-ovarian torsion, especially if a fallopian tube is also involved. Ovarian Torsion
  • Ischemic colitis Ischemic colitis Inflammation of the colon due to colonic ischemia resulting from alterations in systemic circulation or local vasculature. Large Bowel Obstruction
  • Testicular torsion Testicular torsion Testicular torsion is the sudden rotation of the testicle, specifically the spermatic cord, around its axis in the inguinal canal or below. The acute rotation results in compromised blood flow to and from the testicle, which puts the testicle at risk for necrosis. Testicular Torsion
  • Strangulated hernia Hernia Protrusion of tissue, structure, or part of an organ through the bone, muscular tissue, or the membrane by which it is normally contained. Hernia may involve tissues such as the abdominal wall or the respiratory diaphragm. Hernias may be internal, external, congenital, or acquired. Abdominal Hernias

Anatomy

Boundaries of the abdominal cavity

• Superiorly: diaphragm Diaphragm The diaphragm is a large, dome-shaped muscle that separates the thoracic cavity from the abdominal cavity. The diaphragm consists of muscle fibers and a large central tendon, which is divided into right and left parts. As the primary muscle of inspiration, the diaphragm contributes 75% of the total inspiratory muscle force. Diaphragm: Anatomy
• Inferiorly: pelvic inlet Pelvic inlet Pelvis: Anatomy
• Anteriorly: abdominal wall Abdominal wall The outer margins of the abdomen, extending from the osteocartilaginous thoracic cage to the pelvis. Though its major part is muscular, the abdominal wall consists of at least seven layers: the skin, subcutaneous fat, deep fascia; abdominal muscles, transversalis fascia, extraperitoneal fat, and the parietal peritoneum. Surgical Anatomy of the Abdomen muscles and lower ribs Ribs A set of twelve curved bones which connect to the vertebral column posteriorly, and terminate anteriorly as costal cartilage. Together, they form a protective cage around the internal thoracic organs. Chest Wall: Anatomy
• Posteriorly: ribs Ribs A set of twelve curved bones which connect to the vertebral column posteriorly, and terminate anteriorly as costal cartilage. Together, they form a protective cage around the internal thoracic organs. Chest Wall: Anatomy, spine Spine The human spine, or vertebral column, is the most important anatomical and functional axis of the human body. It consists of 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae and is limited cranially by the skull and caudally by the sacrum. Vertebral Column: Anatomy, and paraspinal muscles

External anatomy

For descriptive purposes, the abdomen can be divided into 4 quadrants or 9 regions.

Quadrants:

Divided into 4 quadrants by 2 perpendicular lines crossing at the umbilicus:

Regions:

The abdomen can be divided into regions with 4 lines:

• 2 transverse lines:
  • Subcostal line: through the 10th costal cartilage Cartilage Cartilage is a type of connective tissue derived from embryonic mesenchyme that is responsible for structural support, resilience, and the smoothness of physical actions. Perichondrium (connective tissue membrane surrounding cartilage) compensates for the absence of vasculature in cartilage by providing nutrition and support. Cartilage: Histology
  • Intertubercular line: connects the tubercles of the iliac crests
• 2 vertical lines: right and left midclavicular lines

Internal anatomy

Relationship of intra-abdominal organs to peritoneal cavity Peritoneal Cavity The space enclosed by the peritoneum. It is divided into two portions, the greater sac and the lesser sac or omental bursa, which lies behind the stomach. The two sacs are connected by the foramen of winslow, or epiploic foramen. Peritoneum: Anatomy:

• Intraperitoneal Intraperitoneal Peritoneum: Anatomy:
  • Stomach Stomach The stomach is a muscular sac in the upper left portion of the abdomen that plays a critical role in digestion. The stomach develops from the foregut and connects the esophagus with the duodenum. Structurally, the stomach is C-shaped and forms a greater and lesser curvature and is divided grossly into regions: the cardia, fundus, body, and pylorus. Stomach: Anatomy and small intestine Small intestine The small intestine is the longest part of the GI tract, extending from the pyloric orifice of the stomach to the ileocecal junction. The small intestine is the major organ responsible for chemical digestion and absorption of nutrients. It is divided into 3 segments: the duodenum, the jejunum, and the ileum. Small Intestine: Anatomy
  • Liver Liver The liver is the largest gland in the human body. The liver is found in the superior right quadrant of the abdomen and weighs approximately 1.5 kilograms. Its main functions are detoxification, metabolism, nutrient storage (e.g., iron and vitamins), synthesis of coagulation factors, formation of bile, filtration, and storage of blood. Liver: Anatomy
  • Spleen Spleen The spleen is the largest lymphoid organ in the body, located in the LUQ of the abdomen, superior to the left kidney and posterior to the stomach at the level of the 9th-11th ribs just below the diaphragm. The spleen is highly vascular and acts as an important blood filter, cleansing the blood of pathogens and damaged erythrocytes. Spleen: Anatomy
  • Transverse colon Transverse colon The segment of large intestine between ascending colon and descending colon. It passes from the right colic flexure across the abdomen, then turns sharply at the left colonic flexure into the descending colon. Colon, Cecum, and Appendix: Anatomy
  • Duodenal bulb and pancreatic tail
• Extraperitoneal: bladder Bladder A musculomembranous sac along the urinary tract. Urine flows from the kidneys into the bladder via the ureters, and is held there until urination. Pyelonephritis and Perinephric Abscess
• Retroperitoneal Retroperitoneal Peritoneum: Anatomy organs can be grouped in the SAD PUCKER mnemonic:
  • Suprarenal glands 
  • Aorta and inferior vena cava Inferior vena cava The venous trunk which receives blood from the lower extremities and from the pelvic and abdominal organs. Mediastinum and Great Vessels: Anatomy
  • Duodenum (except the 1st part)
  • Pancreas (except the tail)
  • Ureters
  • Colon (descending and ascending)
  • Kidneys
  • Esophagus
  • Rectum

Pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways and innervation patterns

• Visceral innervation:
  • Innervation of internal organs
  • Senses the distention of a hollow viscus (e.g., stomach Stomach The stomach is a muscular sac in the upper left portion of the abdomen that plays a critical role in digestion. The stomach develops from the foregut and connects the esophagus with the duodenum. Structurally, the stomach is C-shaped and forms a greater and lesser curvature and is divided grossly into regions: the cardia, fundus, body, and pylorus. Stomach: Anatomy, intestines)
  • Pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways:
    • Vague and poorly localized 
    • Epigastric, periumbilical, or hypogastric in location
• Parietal Parietal One of a pair of irregularly shaped quadrilateral bones situated between the frontal bone and occipital bone, which together form the sides of the cranium. Skull: Anatomy innervation:
  • Segmental nerves that innervate the peritoneum Peritoneum The peritoneum is a serous membrane lining the abdominopelvic cavity. This lining is formed by connective tissue and originates from the mesoderm. The membrane lines both the abdominal walls (as parietal peritoneum) and all of the visceral organs (as visceral peritoneum). Peritoneum: Anatomy
  • Transmit the pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways from peritoneal irritation usually secondary to inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation or internal bleeding
  • Sharper and more localized pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways
• Referred pain Referred Pain Spinal Disk Herniation:
  • Pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways perceived at a site different from the source of pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways
  • Secondary to innervation of different sites by the same nerve roots
  • Classic example: diaphragmatic irritation perceived as shoulder pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways due to both structures being innervated by C3–C5 roots

Clinical Presentation

The hallmark of acute abdomen is acute onset of severe abdominal pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways that may or may not be associated with other symptoms. A detailed history and physical exam should be performed to determine the correct course of action.

History

• Description of pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways:
  • Onset
  • Location
  • Duration
  • Description
  • Radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma
  • Severity
  • Aggravating or alleviating factors: Peritonitis Peritonitis Inflammation of the peritoneum lining the abdominal cavity as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the peritoneal cavity via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the abdominal cavity itself through rupture or abscess of intra-abdominal organs. Penetrating Abdominal Injury is classically exacerbated by movement.
• Associated symptoms:
  • Nausea Nausea An unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses. Antiemetics
  • Vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia
  • Diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea
  • Melena Melena The black, tarry, foul-smelling feces that contain degraded blood. Gastrointestinal Bleeding or hematochezia Hematochezia Gastrointestinal Bleeding
  • Fever Fever Fever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever
• Past history:
  • Previous similar episodes
  • Underlying medical conditions
  • Preceding trauma (car accident, assault)
  • Prior abdominal surgeries
  • Recent travel, toxic exposures, food poisoning Food poisoning Acute illnesses, usually affecting the gastrointestinal tract, brought on by consuming contaminated food or beverages. Most of these diseases are infectious, caused by a variety of bacteria, viruses, or parasites that can be foodborne. Sometimes the diseases are caused by harmful toxins from the microbes or other chemicals present in the food. Especially in the latter case, the condition is often called food poisoning. Clostridia

Physical examination

• Exam should always start with visual inspection Inspection Dermatologic Examination to note things such as:
  • Jaundice Jaundice Jaundice is the abnormal yellowing of the skin and/or sclera caused by the accumulation of bilirubin. Hyperbilirubinemia is caused by either an increase in bilirubin production or a decrease in the hepatic uptake, conjugation, or excretion of bilirubin. Jaundice
  • Pallor
  • Work of breathing Work of breathing Respiratory muscle contraction during inhalation. The work is accomplished in three phases: lung compliance work, that required to expand the lungs against its elastic forces; tissue resistance work, that required to overcome the viscosity of the lung and chest wall structures; and airway resistance work, that required to overcome airway resistance during the movement of air into the lungs. Work of breathing does not refer to expiration, which is entirely a passive process caused by elastic recoil of the lung and chest cage. Pulmonary Examination
  • Patient’s behavior:
    • Trying to lie still
    • Grimacing 
• A full set of vital signs should be obtained and constitutional signs noted:
  • Fever Fever Fever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever
  • Tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children
  • Hypotension Hypotension Hypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension
  • Tachypnea Tachypnea Increased respiratory rate. Pulmonary Examination
  • Altered mental status Altered Mental Status Sepsis in Children
• A thorough abdominal exam should be completed:
  • Inspection Inspection Dermatologic Examination:
    • Distention
    • Bruising (Cullen or Grey–Turner sign: hemorrhagic pancreatitis Pancreatitis Inflammation of the pancreas. Pancreatitis is classified as acute unless there are computed tomographic or endoscopic retrograde cholangiopancreatographic findings of chronic pancreatitis. The two most common forms of acute pancreatitis are alcoholic pancreatitis and gallstone pancreatitis. Acute Pancreatitis)
    • Bulging, skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions discoloration (would suggest strangulated hernia Hernia Protrusion of tissue, structure, or part of an organ through the bone, muscular tissue, or the membrane by which it is normally contained. Hernia may involve tissues such as the abdominal wall or the respiratory diaphragm. Hernias may be internal, external, congenital, or acquired. Abdominal Hernias)
  • Percussion Percussion Act of striking a part with short, sharp blows as an aid in diagnosing the condition beneath the sound obtained. Pulmonary Examination:
    • Tympanic (bowel distention or pneumoperitoneum Pneumoperitoneum A condition with trapped gas or air in the peritoneal cavity, usually secondary to perforation of the internal organs such as the lung and the gastrointestinal tract, or to recent surgery. Pneumoperitoneum may be purposely introduced to aid radiological examination. Perforated Viscus)
    •  Dull ( ascites Ascites Ascites is the pathologic accumulation of fluid within the peritoneal cavity that occurs due to an osmotic and/or hydrostatic pressure imbalance secondary to portal hypertension (cirrhosis, heart failure) or non-portal hypertension (hypoalbuminemia, malignancy, infection). Ascites or blood)
  • Auscultation:
    • Typically, acute abdomen will be associated with hypoactive or absent bowel sounds.
    • Can have hyperactive bowel sounds Hyperactive Bowel Sounds Abdominal Examination in cases of high-grade bowel obstruction Bowel obstruction Any impairment, arrest, or reversal of the normal flow of intestinal contents toward the anal canal. Ascaris/Ascariasis
  • Palpation Palpation Application of fingers with light pressure to the surface of the body to determine consistency of parts beneath in physical diagnosis; includes palpation for determining the outlines of organs. Dermatologic Examination:
    • Typically, diffuse tenderness in all quadrants
    • Can have more pronounced tenderness in one site, which could help narrow the diagnosis
  • Peritoneal signs:
    • Rebound tenderness: Pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways is suddenly worse when manual pressure is removed.
    • Guarding: involuntary or voluntary contraction of the abdominal wall Abdominal wall The outer margins of the abdomen, extending from the osteocartilaginous thoracic cage to the pelvis. Though its major part is muscular, the abdominal wall consists of at least seven layers: the skin, subcutaneous fat, deep fascia; abdominal muscles, transversalis fascia, extraperitoneal fat, and the parietal peritoneum. Surgical Anatomy of the Abdomen
    • Rigidity Rigidity Continuous involuntary sustained muscle contraction which is often a manifestation of basal ganglia diseases. When an affected muscle is passively stretched, the degree of resistance remains constant regardless of the rate at which the muscle is stretched. This feature helps to distinguish rigidity from muscle spasticity. Megacolon: constant involuntary abdominal muscle contraction

Diagnosis

Laboratory studies

• CBC:
  • ↑ WBCs
  • ↓ or  ↑ hemoglobin (bleeding versus hemoconcentration Hemoconcentration Neonatal Polycythemia due to dehydration Dehydration The condition that results from excessive loss of water from a living organism. Volume Depletion and Dehydration)
• Basic metabolic panel Basic Metabolic Panel Primary vs Secondary Headaches: ↑ BUN and creatinine 
• Amylase Amylase A group of amylolytic enzymes that cleave starch, glycogen, and related alpha-1, 4-glucans. Digestion and Absorption and lipase Lipase An enzyme of the hydrolase class that catalyzes the reaction of triacylglycerol and water to yield diacylglycerol and a fatty acid anion. It is produced by glands on the tongue and by the pancreas and initiates the digestion of dietary fats. Malabsorption and Maldigestion: ↑ in cases of pancreatitis Pancreatitis Inflammation of the pancreas. Pancreatitis is classified as acute unless there are computed tomographic or endoscopic retrograde cholangiopancreatographic findings of chronic pancreatitis. The two most common forms of acute pancreatitis are alcoholic pancreatitis and gallstone pancreatitis. Acute Pancreatitis
• Hepatic function panel:
  •  ↑ or normal total and direct bilirubin Direct bilirubin Liver Function Tests
  •  ↑ or normal liver Liver The liver is the largest gland in the human body. The liver is found in the superior right quadrant of the abdomen and weighs approximately 1.5 kilograms. Its main functions are detoxification, metabolism, nutrient storage (e.g., iron and vitamins), synthesis of coagulation factors, formation of bile, filtration, and storage of blood. Liver: Anatomy enzymes Enzymes Enzymes are complex protein biocatalysts that accelerate chemical reactions without being consumed by them. Due to the body’s constant metabolic needs, the absence of enzymes would make life unsustainable, as reactions would occur too slowly without these molecules. Basics of Enzymes
• Lactate: high levels indicative of sepsis Sepsis Systemic inflammatory response syndrome with a proven or suspected infectious etiology. When sepsis is associated with organ dysfunction distant from the site of infection, it is called severe sepsis. When sepsis is accompanied by hypotension despite adequate fluid infusion, it is called septic shock. Sepsis and Septic Shock/hypoperfusion
• Urinalysis Urinalysis Examination of urine by chemical, physical, or microscopic means. Routine urinalysis usually includes performing chemical screening tests, determining specific gravity, observing any unusual color or odor, screening for bacteriuria, and examining the sediment microscopically. Urinary Tract Infections (UTIs) in Children: to rule out urinary tract Urinary tract The urinary tract is located in the abdomen and pelvis and consists of the kidneys, ureters, urinary bladder, and urethra. The structures permit the excretion of urine from the body. Urine flows from the kidneys through the ureters to the urinary bladder and out through the urethra. Urinary Tract: Anatomy infection
• Infectious stool panel
• Blood cultures

Imaging studies

• X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests:
  • Upright chest X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests:
    • First-line imaging in evaluating a patient with abdominal pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways to rule out perforated viscus Perforated Viscus Perforated viscus or GI perforation represents a condition in which the integrity of the GI wall is lost with subsequent leakage of enteric contents into the peritoneal cavity, resulting in peritonitis. The causes of perforated viscus include trauma, bowel ischemia, infections, or ulcerative conditions, all of which ultimately lead to a full-thickness disruption of the intestinal wall. Perforated Viscus
    • Can identify as little as 1 mL of intra-abdominal free air
    • Can also reveal significant gastric dilation
  • Lateral decubitus abdominal film:
    • Can detect 5–10 mL of intra-abdominal free air
    • Identifies dilated loops of bowel, air fluid levels Air Fluid Levels Imaging of the Intestines, and volvulus Volvulus A volvulus is the twisting or axial rotation of a portion of the bowel around its mesentery. The most common site of volvulus in adults is the colon; most frequently the sigmoid volvulus. Patients typically present with symptoms of bowel obstruction such as abdominal pain, distension, vomiting, and constipation/obstipation. Volvulus
• Abdominal ultrasonography:
  • Right upper quadrant Right upper quadrant Anterior Abdominal Wall: Anatomy:
    • Gallbladder Gallbladder The gallbladder is a pear-shaped sac, located directly beneath the liver, that sits on top of the superior part of the duodenum. The primary functions of the gallbladder include concentrating and storing up to 50 mL of bile. Gallbladder and Biliary Tract: Anatomy pathology
    • Hepatic pathology
    • Evaluate for free fluid
  • Right lower quadrant Right lower quadrant Anterior Abdominal Wall: Anatomy:
    • Appendiceal pathology
    • Ovarian and adnexal pathology
• CT scan:
  • Second-line test after plain films
  • IV contrast and oral contrast (if tolerating oral intake)
  • Very specific for intra-abdominal pathology:
    • Perforation Perforation A pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force. Esophagitis: free air
    • Bowel obstruction Bowel obstruction Any impairment, arrest, or reversal of the normal flow of intestinal contents toward the anal canal. Ascaris/Ascariasis with dilated loops of bowel and air fluid levels Air Fluid Levels Imaging of the Intestines
    • Bowel ischemia Bowel ischemia Mesenteric ischemia is a rare, life-threatening condition caused by inadequate blood flow through the mesenteric vessels, which results in ischemia and necrosis of the intestinal wall. Mesenteric ischemia can be either acute or chronic. Mesenteric Ischemia with pneumatosis, enhancing intestinal walls and portal venous gas Portal Venous Gas Imaging of the Intestines
    • Intra-abdominal hematoma Hematoma A collection of blood outside the blood vessels. Hematoma can be localized in an organ, space, or tissue. Intussusception: with IV contrast can identify a vascular source

Management

Acute abdomen is a surgical emergency or urgency in the vast majority of cases. The initial evaluation should determine the cases that do not require surgical treatment.

Initial management

Resuscitation Resuscitation The restoration to life or consciousness of one apparently dead. . Neonatal Respiratory Distress Syndrome:

• The first step should always be resuscitation Resuscitation The restoration to life or consciousness of one apparently dead. . Neonatal Respiratory Distress Syndrome of the patient.
• Obtain reliable large-bore IV access.
• Fluid bolus of 30 mL/kg for hypotension Hypotension Hypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension and tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children
• Electrolyte correction
• Airway Airway ABCDE Assessment protection/mechanical ventilation Ventilation The total volume of gas inspired or expired per unit of time, usually measured in liters per minute. Ventilation: Mechanics of Breathing for impaired mental status or respiratory distress
• Broad-spectrum Broad-Spectrum Fluoroquinolones IV antibiotics can be administered empirically.
• Pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways management

Evaluation:

• Thorough history and physical exam 
• Obtain labs, including CBC, basic metabolic panel Basic Metabolic Panel Primary vs Secondary Headaches, lactate, hepatic function panel.
• Early blood cultures
• Imaging:
  • In the majority of cases, there is at least time to obtain an upright chest X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests to evaluate for free air.
  • Free air on imaging is an indication for immediate surgical intervention.
  • Without evidence of free air in a stable patient, there is time to obtain a CT scan.

Operative management

Surgical treatment is usually needed unless a nonsurgical cause has been established. If surgical intervention is warranted, there are two approaches:

• Diagnostic laparoscopy Diagnostic Laparoscopy Laparotomy and Laparoscopy:
  • Minimally invasive approach using a laparoscope Laparoscope Endoscopes for examining the abdominal and pelvic organs in the peritoneal cavity. Laparotomy and Laparoscopy to explore the abdomen
  • Most helpful in triaging the abdomen and deciding whether an open approach is needed
  • Sometimes, a definitive intervention can be performed laparoscopically.
  • Technically limited in difficult-to-access areas and complex surgical repairs
  • Should be avoided in cases of significantly dilated bowel owing to risk of perforation Perforation A pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force. Esophagitis with port insertion and laparoscopic instruments
  • Should not be performed in cases in which diagnosis is clear and open intervention will definitely be required
• Exploratory laparotomy Exploratory Laparotomy Laparotomy and Laparoscopy:
  • Open surgical approach, typically through a midline incision
  • Allows for visual and tactile examination of all the abdominal quadrants and their contents
  • Approach of choice in cases of gross abdominal contamination with bile Bile An emulsifying agent produced in the liver and secreted into the duodenum. Its composition includes bile acids and salts; cholesterol; and electrolytes. It aids digestion of fats in the duodenum. Gallbladder and Biliary Tract: Anatomy or enteric contents
  • Allows for repair of the source of contamination as well as irrigation of the abdominal cavity