Introduction Complaints related to abdominal pain comprise between 7- 9 % of all visits to the ED. ...

Introduction Complaints related to abdominal pain comprise

between 7- 9 % of all visits to the ED.

Of those, the most common discharge diagnosis is Abdominal Pain NOS.

Although most abdominal pain is non-emergent and self-limited in nature, attention must be paid to not miss medical and/or surgical emergencies.

Important Factors

Patients rarely present with the classical signs/symptoms of acute abdominal pain.

Three important factors to consider are age, gender, and co-morbidities.

Definition

The term acute abdomen refers to a sudden, severe abdominal pain that is less than 24 hours in duration. It is in many cases a medical emergency, requiring urgent and specific diagnosis. Several causes need surgical treatment.

Don’t forget about the chronic pain that has acutely worsened.

Basic Principles Proper evaluation and management requires one to recognize:

1. Does this patient need surgery?2. Is it emergent, urgent, or can wait?

• In other words, is the patient unstable or stable?

Remember medical causes of abd pain

> 100 causes exist1. NSAP (34%)2. Acute appendicitis (28%)3. Acute chlecystitis (10%) 4. SBO (4%)5. Perforated PU (3%)6. Pancreatitis (3%)7. Diverticular disease (2%) 8. Others (13%)

50-65% inaccurate initial diagnosis 50% of surgical admissions are emergencies, and of

those 50% present with acute abdomen.

In children

Acute appendicitis

UTI

Mesenteric adenitis

GE

Constipation

Types of Pain

Visceral Pain: caused by stretching of fibers innervating the walls of hollow organs or capsules of solid organs, described as cramp or dull pain

Parietal Pain: caused by irritation of fibers that innervate the parietal peritoneum, pain is more sharp and localized

Referred Pain: pain at a location distant to the diseased organ based on embryological origin

Visceral pain

I. Parietal pain Is localised to the dermatome above

the site of the stimulus. Character:I. sharp and localized pain.II. somatic nerve distribution (T7-L2,

umbilicus at T12). The exception to this is the diaphragmatic portion, which is supplied centrally by the phrenic nerve (C3-C5), and peripherally by the lower six intercostal and subcostal nerves.

III.sensitive to mechanical stimuli (stretching, pinprick , pinch), heat, electrical shock, chemical stimulus, infection-inflammation.

II. Referred pain It’s pain perceived distant from its

source and results from convergence of nerve fibers at the spinal cord.

produces symptoms, not signs e.g. tenderness

Causes of Acute Abdomen

I. Surgical

II. Gynecological

III. Medical

Think Broad categories for DDx surgical Causes

o Inflammationo Obstructiono Ischemiao Perforation (any of above can end here)

Offended organ becomes distendedLymphatic/venous obstruction due to ↑ pressureArterial pressure exceeded → ischemiaProlonged ischemia → perforation

Inflammation versus ObstructionOrgan Lesion

Stomach Gastric UlcerDuodenal Ulcer

Biliary Tract

Acute cholecystitisAcute cholangitis

Pancreas Acute, recurrent, or chronic pancreatitis

Small Intestine

Crohn’s diseaseMeckel’s diverticulum

Large Intestine

AppendicitisDiverticulitis

Location Lesion

Small Bowel Obstruction

AdhesionsHernia CancerCrohn’s diseaseGallstone ileusIntussusceptionVolvulus

Large BowelObstruction

MalignancyVolvulus: cecal or sigmoidDiverticulitis

Biliary colic

Ureteric colic

Acute retention

Ischemia versus Perforation

Acute mesenteric ischemia

Usually acute occlusion of the SMA from thrombus or embolism

Chronic mesenteric ischemia

Typically smoker, vasculopathy with severe atherosclerotic vessel disease

Ischemic colitis

Torsion of a viscus

Perforated PU

Perforated diverticular disease

Perforated appendix

Acute chlolecystitis with Perforation

Ruptured AAA

Perforated bladder

GYN Causes

Organ Lesion

Ovary Torsion of ovaryRuptured graafian follicleTubo-ovarian abscess (TOA)

Fallopian tube Ectopic pregnancyAcute salpingitisPyosalpinx

Uterus Uterine ruptureEndometritis

Non-Surgical (Medical) Causes

System Disease System DiseaseCardiac Myocardial infarx

Acute pericarditisEndocrine Diab ketoacidosis

Addisonian crisis

Pulmonary PneumoniaPulmonary infarxPE

Metabolic Acute porphyriaMediterranean feverHyperlipidemia

GI Acute pancreatitisGastroenteritisAcute hepatitis

Musculo- skeletal

Rectus muscle hematoma

GU Pyelonephritis CNSPNS

Tabes dorsalis (syph)Nerve root compression

Vascular Aortic dissection Hematological Sickle cell crisis

Generalized AP

PerforationMesenteric ischemia AAAAcute pancreatitis

Central APEarly appendicitisSBOAcute pancreatitisRuptured AAAMesenteric thrombosisAcute gastritis

Epigastric painDU / GU Recurrent, relationship to meals,relationship to posture

OesophagitisAcute pancreatitis History of alcohol consumption,

history of similar event, elevated labs

AAA

RUQ painAcute cholecystitisRecurrent attacks, tender over gall bladder area

DUAcute pancreatitis Retrocecal appendicitisShift of pain, tenderness

R L PneumoniaFever, tachypnea, bronchial breathing

Subphrenic abscess

LUQ pain

PneumoniaAcute pancreatitisSplenic ruptureSplenic abscessAcute perinephritisSubphrenic abscess

RIF pain Acute appendicitisShift of pain, anorexia, localized tenderness

Mesenteric adenitis (young)Fever, inconstant signs

Perf DU Diverticulitis Salpingitis Ureteric colic Colicky pain, hematuria

Meckel’s diverticulum Ectopic pregnancy Crohn’s disease Biliary colic (low-lying GB)

LIF painDiverticulitisConstipation IBSPIDRectal CaUCEctopic pregnancy

Suprapubic painAcute urinary retentionPalpable bladder, difficulty passing urine

UTICystitis PIDEctopic pregnancy Diverticulitis

Loin painMuscle strainUTIsRenal stonesPyelonephritis

Approach to Acute Abdomen

Take a proper Hx and Ex, do not work to the diagnosis given to you by the referring doctor.

History is THE MOST IMPORTANT part of the diagnostic process:Location , onset, nature , severity, radiation, aggravating or

relieving factors, associated symptoms

A good medical historyA good social history, including alcohol, drugs, domestic

abuse, stressors, etc.Family history is important (IBD, cancers, etc)MEDICATION INVENTORY

What does nature of pain?Steady pain inflammatory processColicky pain Biliary colic ,obstructionStabbing AAA

Was onset of pain gradual or sudden?Sudden perforation, hemorrhage, infarctGradual inflammation, peritoneal irrigation, hollow organ distension

Does pain radiate anywhere? Right shoulder, angle of right scapula GB Around flank to groin kidney, ureter

In Females ?Last menstrual period? Abnormal bleeding?

CLUES in Hx.

Progression of Pain

Associated symptoms

• Fever

• Genitourinary

• Gynaecological

• Vascular

PMSH

• Previous episodes of AP

• Investigations

• Operations

• Chronic disease

• Medications (NSAIDs)

Physical examination

Administration of analgesics prior to surgical consultation does not obscure the diagnosis, but improves accuracy.

ObservationBending Forward: Chronic PancreatitisJaundiced: CBD obstructionDehydrated: Peritonitis, SBO

Inspection Not move with respiration in peritonitis Scaphoid or flat in peptic ulcer Distended in ascites or intestinal obstruction Visible peristalsis in a thin or obstruction Scars : relevant previous illness or adhesions Hernia : intestinal obstraction

Palpation Check for Hernia sitesTendernessRebound tenderness.Guarding.Rigidity.

Rebound tenderness, considered the clinical indicator of peritonitis, has a high (25%) false -ve rate

Rigidity, referred tenderness & cough pain are sufficient evidence for peritonitis

Local Right Iliac Fossa tenderness:Acute appendicitisAcute Salpingitis in females

Low grade, poorly localized tenderness: Intestinal Obstruction

Tenderness out of proportion to examination:Mesenteric IschemiaAcute Pancreatitis

Flank Tenderness:Perinephric AbscessRetrocaecal Appendicitis

Important Signs in Patients with Abdominal Pain

Sign Finding Association

Cullen's sign Bluish periumbilical discoloration Retroperitoneal haemorrhage

Kehr's sign referd left shoulder pain Splenic ruptureEctopic pregnancy

rupture

McBurney's sign Tenderness located 2/3 distance fromanterior iliac spine to umbilicus on right side

Appendicitis

Murphy's sign Abrupt interruption of inspiration on palpationof right upper quadrant

Acute cholecystitis

Iliopsoas sign Hyperextension of right hip causing abdominal pain Appendicitis

Obturator's sign Internal rotation of flexed right hip causingabdominal pain

Appendicitis

Grey-Turner's Discoloration of the flank Retroperitoneal hemorrhage

Chandelier sign Manipulation of cervix causes patient to liftbuttocks off table

PID

Rovsing's sign Right lower quadrant pain with palpation of the left lower quadrant

Appendicitis

Percussion Resonance : intestinal obstructionLoss of liver dullness: gastrointestinal perforationDullness : free fluid , full bladderShifting dullness : free fluid

Auscultation NR Bowel sounds 5-30/min > 2min to confirm absent High pitched, hyperactive or tinkling

caused by powerful peristaltic action , partial obstruction , abdominal cramping

Hypoactive bowel sounds indicates Peritonitis , non-mechanical obstruction , Inflammation , gangrene

Bruit in epigastrium indicates AAA

Systemic Examination

PR Examination: Tenderness Induration Mass Frank blood

Systemic Examination

PV Examination Bleeding Discharge Cervical motion tenderness Adnexal masses or tenderness Uterine Size or Contour

Investigations Beware of misleading by investigationsA.Blood testsCBC (Hb & WBC) & U&EAmylase (Pancreatitis) but remember 20% have NR values

LFTs CRP & ESR (inflammatory markers)

ABG Serum calcium (Abnormal GI motility PU, Pancreatitis)

Clotting (acute pancreatitis, sepsis, DIC, liver disease)

Blood glucose ECG

Attention to the WBC as a screening test only if substantially elevated. 25% of patients with elevated WBC do not have

different outcomes from those with a normal WBC. CBC has a limited clinical utility

In RLQ pain to rule in or rule out Acute Appendicitis wbc count (n>70%) < 8,000 very unlikely 8,000-10,000 unlikely10,000-12000 equivocal12,000-15,000 suggestive15,000-20,000 highly suggestive>20,000 probably ruptured

B. UrinalysisCheapSimple & available testHigh yield when results fit with the clinical scenario Pregnancy test

C. RadiologyErect CXRSupine AXRUSS Biliary trees , Mass , fluid , Retroperitoneal organs Ultrasound in Acute Appendicitis +!?

IVU (renal/ureteric colic)CT scan Similar benefit as in U/S but more time consumed , more accurate more expensive more risk

Causes of free sub-diaphragmatic gas

Perforation of viscus

Gas-forming infection

Pleuroperitoneal fisula

Iatrogenic

Interposition of bowel b/t liver & diaphragm

Plain X-rays have limited utility in the evaluation of AAP Low diagnostic yieldHigh incidence of misleading incidental

findingsLack of impact on management Exception: Bowel obstruction or perforation

Labs & Imaging

Test ReasonCBC w diff Left shift can be

very telling

ABG N/V, acidosis, dehydration

Amylase Pancreatitis, perf DU, bowel ischemia

LFT Jaundice,hepatitis

UA GU- UTI, stone, hematuria

Beta-hCG Ectopic

Test Reason

KUBFlat & Upright

SBO/LBO, free air, stones

Ultrasound Chol’y, jaundiceGYN pathology

CT scanDiagnostic accuracy

Anatomic dxCase not straight forward

Findings in plain X-ray abdomen in case of Biliary disease : 1. radioopaque shadow for stone

2. pneumobilia

3. calcification of porcelain gallbladder

In case of pancreatic disease :1. calcification in chronic pancreatitis

2. sentinel loop : dilatation of a segment of large or small intestine, indicative of localised ileus from nearby inflammation.

In case of appendicitis:1. Fecalith: a hard stony mass of feces

2. Phlebolith : is a small local, usually rounded, calcification within a vein

3. Abscent of psoas muscle shadow

calcification of porcelain gallbladder

Pneumoperitoneum

Findings in plain X-ray abdomen

Intestinal obstruction

SBO

Erect (air fluid level)

Step ladderCentralSmall

multiple

Supine(dilatation of bowel)

>3cmplicae circulares

LBO

Erect(air fluid level)

PeripheralLargeFew

Supine(dilatation of bowel)

> 5cm in sigmoid> 10 cm in cecum

Peripheral haustration

ultrasound.

Hepatobiliray tree(stones,mass,thickining of the wall)

*pancreases

*kidney

*pelvic organ

*intrabdominal fluid collection

Gall stone\ appendicolith

CT scan.

Helpful in case of abdominal pain without clear etiology better in evaluation of abdominal aortic aneurysm.

5.helical CT_scan

Provide rapid cost effective diagnostic tool.

CT scan

What is the diagnosis? Acute appendicitis

Acute pancreatitis

D. Laparoscopy

Early diagnostic laparoscopy may result in:accurate, prompt, efficient management of AAP

Reduces the rate of unnecessary laparotomy Increases the diagnostic accuracyMay be a key to solving the diagnostic dilemma of

NSAP.

Immediate Treatment of the Acute Abdomen

I. Start large bore IV with either saline or lactated Ringer’s solution

II. IV pain medicationIII. Nasogastric tube if vomiting or concerned about obstruction.IV. Foley catheter to follow hydration status and to obtain

urinalysis.V. Antibiotic administration if suspicious of inflammation or

perforation.VI. Definitive therapy or procedure will vary with diagnosis.VII. Reassess patient on a regular basis.

Decision to operate• Proper management requires a timely decision about

the need for surgical operation.Peritonitis

Tenderness w/ rebound, involuntary guardingSevere / unrelenting pain “Unstable” (hemodynamically, or septic)

Tachycardic, hypotensive, white count Intestinal ischemia, including strangulationPneumoperitoneumComplete or “high grade” obstruction

Take Home Massage Careful history (pain, other GI symptoms) Remember DDx in broad categories Narrow DDx based on hx, exam, labs, imaging Always perform ABC, Resuscitate before Dx If patient’s sick or “toxic”, get to OR (surgical

emergency) Ideally, resuscitate patients before going to the OR Don’t forget GYN/medical causes, special situations For acute abdomen, think of these commonly (below)

Perf DU Appendicitis +/- perforation

Diverticulitis +/- perforation

Bowel obstruction

Cholecystitis Ischemic or perf bowel

Ruptured aneurysm

Acute pancreatitis