Acute Abdominal Pain¶

Alex Mamunes

General Approach¶

Rule out life threatening causes: Obstruction, Perforation, Dissection, AAA rupture, Inferior MI, Ectopic Pregnancy
History: pain quality/timing/location/severity, aggravating and alleviating factors (eating, bowel movements, position), nausea/emesis, bowel changes, flatus & prior episodes
Initial labs: CBC, BMP, LFTs, INR, lactate, lipase, U/A, urine hCG

System	Causes	Common features	Workup
Esophagus	Esophagitis – GERD, EOE, candida, HSV, CMV, pill, functional	Epigastric pain, nocturnal reflux, odynophagia, dysphagia, thrush, immunocompromised	Trial PPI, nystatin swish and swallow, consider EGD
Stomach	Dyspepsia	Epigastric pain, indigestion, bloating	H. pylori testing, Trial PPI, ± EGD
	Peptic ulcer disease	NSAID use, better or worse w/ food, ± melena	CBC, H. pylori testing, EGD
	Gastritis	NSAID use, ETOH abuse, burning epigastric pain
Liver	Hepatitis: Ischemic, Viral, ETOH, trauma, toxins, autoimmune, congestive	RUQ pain ± jaundice EtOH, Tylenol or IVDU	LFTs, INR, ETOH, Tylenol lvl, viral panel, RUQ U/S + dopplers; CT
Spleen	Splenomegaly: increased size, infarct, abscess	LUQ pain	Physical exam, CT
Biliary	Biliary colic	Overweight, ♀, 40’s, lasts hrs, worse with food, RUQ pain scapula	LFTs, RUQ U/S
	Cholecystitis	RUQ pain (Murphy’s sign), nausea, emesis with fever
	Choledocholithiasis	RUQ pain, N/V with jaundice	CBC, LFTs, RUQ U/S, blood cx
	Ascending cholangitis	RUQ pain, N/V, jaundice, fever; hypotension, AMS
Pancreas	Acute or chronic Pancreatitis; Complications (fluid, collection, necrosis, pseudocyst)	ETOH use, gallstones, epigastric pain back, N/V Chronic pancreatitis: calcifications on CT	Lipase, CT A/P (rarely necessary within 24-48 hrs), RUQ U/S for gallstones
Intestines	Gastroenteritis	N/V, sick contact, undercooked food, travel	Supportive care
	Diverticulitis	Older, h/o diverticulosis, LLQ pain with fever	CBC (leukocytosis) CT A/P w contrast
	Constipation	h/o IBS, narcotic use, unable to pass stool, straining	KUB
	Bowel Obstruction/Ileus	Prior hernia, abd surgery or malignancy, pain, nausea, emesis, distention inability to pass stool or flatus	KUB (air fluid levels) CT is more sensitive If concerned, page EGS and consider NGT to suction
	Acute Small Bowel Mesenteric Ischemia	Vascular disease, A-Fib, dissection, thrombosis, rapid onset, severe, periumbilical with N/V, recent hypotensive episode, post-prandial	CBC (leukocytosis) BMP (metabolic acidosis), Lactate CT A/P w contrast (CTA if suspicion)
	Colonic non-occlusive Mesenteric Ischemia: ischemic colitis	Cramping pain, laterally (most often left), urge to defecate + hematochezia	CBC, BMP, Lactate CT A/P w contrast +/- colonoscopy
	Appendicitis	Periumbilical to RLQ with N/V, later fever	CBC, Lactate, CT A/P w/contrast
	IBD Flare	H/o Crohn’s or UC, Abd pain, fever, diarrhea, hematochezia	CBC, Lactate, CTE, ESR, CRP, C-diff, GIPP
	C. diff colitis	Antibiotic exposure, diarrhea, abdominal cramping	C-diff PCR, CBC (leukocytosis) KUB (megacolon)
	Ogilvie’s syndrome	Pseudo-obstruction in elderly pt, signs of obstruction w/o mechanical cause	CBC, lactate, CT A/P w contrast
	Volvulus	Progressive abdominal pain, nausea, distention, constipation, vomiting	CBC, lactate CT A/P w contrast
	Typhlitis	Neutropenia, abdominal pain (often RLQ), fever	CBC with diff, CT A/P w/ contrast, blood cx, C-diff; empiric abx
OBGYN	Ectopic pregnancy	Sexually active, 6-7 wks after LMP, RLQ or LLQ pain + vaginal bleeding	Urine hCG, pelvic US, CBC, T&S
	Pelvic inflammatory disease, endometritis, Tubo-ovarian abscess	Sexually active, h/o STI, purulent discharge, cervical motion tenderness, ± fever	Pelvic exam w/ culture, GC probe, pelvic US
	Ovarian torsion	Young, sudden onset & severe, often with N/V	Pelvic US w/ doppler
Kidney	Nephrolithiasis	h/o kidney stones, Crohn’s disease, sharp flank pain, paroxysms, ± hematuria	U/A, CT A/P without contrast
	UTI	Suprapubic pain, dysuria, cloudy urine, new odor	U/A with culture
	Pyelonephritis	Flank pain, fever/chills, CVA tenderness, usually UTI symptoms	U/A with culture, BMP CT A/P w/contrast
	Urinary Retention	Older pt, male with BPH, anticholinergics	Post-void residual
	Renal infarct	h/o vascular disease or A-fib, acute flank pain with N/V, +/- fever, HTN	CBC, BMP, UA, ECG (r/o a-fib) CT A/P w contrast
Vascular	Myocardial infarction	CAD risk factors, DoE, epigastric, diaphoresis	ECG, troponin
	Aortic Dissection	Vascular Risk factors, sudden onset, tearing pain back	CT dissection rule out
	AAA rupture	Vascular risk factors, sudden onset back, hypotensive, pulsatile abdominal mass	CT A/P w contrast, consult vascular surgery
MSK/skin	Herpes zoster	Immunocompromised, dermatomal rash, burning pain	Physical exam Vesicle PCR for zoster
	Muscle strain	h/o trauma, overuse, heavy exercise, worse with twisting or bending	Physical exam; rest, NSAIDs
	Hernia	Bulge, worse w/valsalva	CT A/P non con
Pulmonary	Pneumonia	Productive cough, fever	CXR, CBC, sputum cx
Pulmonary	Pulmonary embolus	Tachycardia, tachypnea, hypoxemia	ECG, trop, BNP CTA chest
Functional	IBS, depression, dyspepsia, anxiety abdominal migraine, functional	Imaging negative Otherwise negative workup	Above workup
Other	Adrenal crisis	Hypotension, fatigue, lethargy, N/V, weight loss, hyperpigmentation	BMP (↓Na, ↑K, ↓ Glu) Cort. stim
	Intra-abdominal abscess	Prior intra-abdominal disease or surgery, fever	CBC, blood cx CT A/P w/ contrast
	DKA	Nausea, emesis, general abdominal pain	CBC, BMP, U/A β–hydroxy butyrate
	Hypercalcemia	N/V, constipation, ↑ thirst, ↑ urination, bone pain, muscle weakness, confusion, fatigue	BMP, ionized calcium, PTH, Vit D, PTHrp
	Acute intermittent porphyria	Severe, poorly localized with motor/sensory neuropathy, red urine, tachycardia	Urinary PBG

Last update: 2022-06-13 17:10:28