01Approach to the Critical Patient/attcp38

Alarm features and escalation triggers

›Red flag recognition

›Pain duration >5-6 hours

›Transition from biliary colic to acute cholecystitis

›Urgent surgical consultation required

›Fever or rigors

›Cholecystitis or cholangitis concern

›Blood cultures and antibiotics if sepsis suspected

›Jaundice or dark urine

›Choledocholithiasis or Mirizzi syndrome

›MRCP or ERCP pathway

›Peritoneal signs

›Rebound tenderness or guarding

›Perforation or gangrenous cholecystitis concern

›Altered mental status in elderly

›May be the only presentation of complicated biliary disease

›Low threshold for full workup

›Elevated lipase

›Gallstone pancreatitis exclusion mandatory

Hemodynamic and monitoring priorities

›Initial stability assessment

›Vitals in uncomplicated biliary colic typically normal

›Tachycardia or hypotension signals complication

›SBP <90 mmHg triggers resuscitation

›IV access and cardiac monitor for hemodynamically unstable patients

›NPO during active pain episode

›Fluid resuscitation if dehydrated from vomiting

›ECG for epigastric or retrosternal pain

02History/hx70

Presenting symptoms

›Pain characteristics

›Steady, severe RUQ or epigastric pain

›Misnomer — not truly colicky or crampy

›Peaks within approximately 1 hour

›Duration 1-5 hours

›Resolves gradually over hours

›Pain >5-6 hours suggests cholecystitis

›Radiation pattern

›Right scapula or right shoulder

›Retrosternal area in approximately 7% of cases

›Associated symptoms

›Nausea and vomiting

›Common in acute episode

›Inability to tolerate PO is a severity marker

›Absence of fever or chills

›Fever distinguishes cholecystitis

›Rigors suggest cholangitis

›Absence of jaundice

›Jaundice raises concern for choledocholithiasis

Timing and triggers

›Postprandial pattern

›Fatty or greasy meal as classic trigger

›Pain not exclusively postprandial

›Nocturnal pain common due to diurnal biliary rhythm

›Diurnal rhythm peak at midnight

›Patients may present overnight

›Nocturnal occurrence distinguishes from functional dyspepsia

03Physical Exam/exam45

Vital signs

›Vital signs interpretation

›Normal vitals expected in uncomplicated biliary colic

›Fever or tachycardia signals complication

›Hypotension triggers immediate reassessment

›Temperature

›Afebrile in uncomplicated biliary colic

›Fever >38 C raises cholecystitis or cholangitis concern

›Heart rate

›Tachycardia from pain or dehydration

›Vagal bradycardia possible from biliary distension

Abdominal exam

›RUQ assessment

›RUQ tenderness

›Voluntary guarding may be present

›Involuntary guarding or rigidity suggests complication

›Murphy sign

›Inspiratory arrest during RUQ palpation

›LR+ 11.5-21.3 for cholecystitis

›Should be negative in simple biliary colic

›Palpable gallbladder mass

›Uncommon finding

›Suggests cholecystitis present >24 hours

›Peritoneal assessment

›Rebound tenderness

›Perforation or gangrenous cholecystitis

›Requires urgent surgical consultation

›Overall clinical gestalt

04Differential Diagnosis/ddx63

Life-threatening diagnoses

›Ascending cholangitis

›ICD-10 K83.0

›Charcot triad: fever, jaundice, RUQ pain

›Reynolds pentad adds AMS and hypotension

›Medical emergency requiring emergent ERCP and antibiotics

›30-day mortality up to 10% in severe cases

›Blood cultures and broad-spectrum antibiotics immediately

›Acute coronary syndrome

›ICD-10 I21.x

›Inferior MI can mimic RUQ or epigastric pain

›ECG changes in leads II, III, aVF

›Troponin and ECG mandatory in atypical presentations

›Especially in patients with cardiac risk factors

›Vagal stimulation from biliary distension may cause bradycardia

Common biliary diagnoses

›Acute cholecystitis

›ICD-10 K81.0

›Pain lasting >6 hours with fever and leukocytosis

›Murphy sign positive in majority

›Tokyo Guidelines severity classification applies

›Grade I mild, Grade II moderate, Grade III severe

›Urgent cholecystectomy within 24-72 hours

›Choledocholithiasis

›ICD-10 K80.5

›Jaundice, elevated bilirubin, ALP, GGT

›Bilirubin elevation OR 3.0 for CBD stones

›MRCP or EUS for confirmation

05Laboratory Tests/lt45

Core biliary labs

›Complete blood count

›WBC normal in uncomplicated biliary colic

›Leukocytosis >11 x10^9/l suggests cholecystitis or cholangitis

›Leukopenia rare but signals severe sepsis

›Haemoglobin

›Haemolytic anaemia as pigment stone risk factor

›Baseline for surgical planning

Liver function and biliary markers

›Liver function tests

›AST and ALT

›Mildly elevated in biliary colic permissible

›Marked elevation suggests hepatocellular injury or cholangitis

›Total and direct bilirubin

›Elevated in choledocholithiasis (OR 3.0)

›Bilirubin may rise to approximately 70 micromol/l even without CBD stones

›Alkaline phosphatase and GGT

›Elevated ALP and GGT suggest biliary obstruction

›More specific than transaminases for CBD stones

›Lipase

›Elevation >3x upper limit suggests gallstone pancreatitis

›Amylase less sensitive and less specific

›Pancreatitis changes management to admission

›Normal lipase supports uncomplicated biliary colic

›Does not exclude mild pancreatic inflammation

›Recheck if symptoms persist or worsen

Inflammatory and metabolic labs

›C-reactive protein

06Diagnostic Tests/dt83

Scoring Systems

›Tokyo Guidelines severity scoring for cholecystitis

›Grade I mild cholecystitis

›No organ dysfunction

›Responds to conservative management

›Grade II moderate cholecystitis

›Leukocytosis >18 x10^9/l

›Palpable tender mass in RUQ

›Symptoms >72 hours duration

›Grade III severe cholecystitis

›Cardiovascular, neurological, respiratory, renal, or hepatic dysfunction

›Coagulopathy (INR >1.5)

›Emergent cholecystectomy or percutaneous drainage

›GRACE-2 low-risk recurrent abdominal pain criteria

›Supports discharge for uncomplicated presentations

›Normal labs, resolved pain, tolerating PO

›Society for Academic Emergency Medicine 2022 guidance

›Identifies patients safe for outpatient surgical referral

›Follow-up within 2 weeks with general surgery

›Primary care follow-up within 1 week if no surgical referral yet established

MRI

›MRCP (Magnetic Resonance Cholangiopancreatography)

›Primary indication

›Suspected choledocholithiasis or biliary obstruction

›Non-invasive alternative to ERCP for diagnosis

›Performance characteristics

›Sensitivity >90% for CBD stones

›Specificity >95% for biliary ductal pathology

›Technical considerations

›No ionising radiation; preferred in pregnancy

›Gadolinium contrast avoided in first trimester

›May miss very small stones <3 mm

›MRI abdomen

›Role in biliary colic workup

›Characterises gallbladder wall in indeterminate US findings

›Evaluates for gallbladder adenomyomatosis or polyps

›Limitations

›Limited availability in acute ED setting

›Longer acquisition time than CT

›Claustrophobia and metallic implant contraindications

CT

›CT abdomen and pelvis

›Role in biliary colic

›Often first-line for undifferentiated abdominal pain in ED

›Detects complications: perforation, abscess, pancreatitis

›Limitations for gallstones

›Only approximately 10-15% of gallstones are calcified and visible on CT

›Sensitivity for gallstones far inferior to ultrasound

›Negative CT does not exclude cholelithiasis

›Preferred CT indications

›Peritoneal signs suggesting perforation

›Concern for alternative diagnosis (appendicitis, renal colic, aortic pathology)

›Gallstone pancreatitis severity assessment

›CT with intravenous contrast

›Cholecystitis assessment

›Gallbladder wall thickening >4 mm

›Pericholecystic fat stranding

›Pericholecystic fluid collection

›Dual-energy CT

›Improved detection of cholesterol stones compared to conventional CT

›Emerging technique not yet standard of care

Ultrasound

›Right upper quadrant ultrasound

›First-line imaging for biliary colic

›Sensitivity >95% and specificity >95% for gallstones

›Evaluates gallbladder wall thickness, pericholecystic fluid, CBD diameter

›Key sonographic findings in biliary colic

›Echogenic foci with posterior acoustic shadowing

›Mobility of stones with patient position change

›Normal CBD diameter <6 mm

›Cholecystitis features on ultrasound

›Gallbladder wall thickening >4 mm

›Pericholecystic fluid

›Sonographic Murphy sign positive

›Point-of-care ultrasound (POCUS)

›Performance characteristics

›LR+ 7.5 for gallstones

›LR- 0.1 for gallstones

›Comparable to radiology-performed ultrasound for stones

›Sonographic Murphy sign

›Maximal tenderness with probe over gallbladder

›More specific than clinical Murphy sign

›Positive in cholecystitis, should be absent in biliary colic

›CBD assessment

›Dilation >6 mm suggests choledocholithiasis

›Dilation >8 mm in post-cholecystectomy patients still significant

›ACEP Level B recommendation for POCUS in biliary evaluation

07Disposition/dispo40

Discharge criteria

›Safe discharge requirements

›Pain resolution with ED treatment

›Patient comfortable at rest

›Tolerating oral fluids

›Normal laboratory results

›No leukocytosis

›Normal LFTs and lipase

›Normal bilirubin or only mild elevation

›No alarm features present

›Afebrile

›No peritoneal signs

›No jaundice

›Reliable follow-up arranged

›General surgery referral within 2 weeks

›Primary care follow-up within 1 week if surgery not yet arranged

Admission criteria

›Indications for admission

›Refractory pain

›Pain not controlled with ED medications

›Unable to tolerate PO due to pain or vomiting

›Laboratory abnormalities suggesting complication

›Leukocytosis indicating cholecystitis

›Elevated bilirubin or ALP suggesting CBD stone

›Elevated lipase indicating pancreatitis

›Clinical concern for complicated disease

›Suspected cholecystitis based on clinical exam

›Suspected cholangitis requiring IV antibiotics

08Treatment/t75

Analgesia

›NSAIDs first-line

›Ketorolac IV

›Standard dose: 30 mg IV

›Reduced dose for age >65, weight <50 kg, or renal impairment: 15 mg IV

›NNT approximately 3 vs placebo

›Cochrane review supports NSAIDs over opioids and antispasmodics

›Diclofenac IM

›75 mg IM as alternative NSAID

›Comparable efficacy to ketorolac

›Avoid in third-trimester pregnancy and active GI bleeding

›NSAID contraindications

›Renal impairment

›Active peptic ulcer or GI bleeding

›Third-trimester pregnancy

›Severe heart failure

›Opioid analgesia

›Morphine

›0.1 mg/kg IV for severe pain refractory to NSAIDs

›May cause sphincter of Oddi spasm — clinical significance debated

›Titrate to pain relief in 2-4 mg increments IV

›Hydromorphone

›0.5-1 mg IV as alternative opioid

›Useful in morphine-sensitive patients

›Same sphincter of Oddi concern theoretically

›Adjunct analgesia

›IV acetaminophen

›1 g IV over 15 minutes

09Special Populations/sp99

Pregnancy

›Prevalence and risk

›Gallstone disease in pregnancy

›Pregnancy is an independent risk factor for gallstones

›Progesterone impairs gallbladder motility

›Estrogen increases cholesterol secretion into bile

›Incidence 0.05-0.3% of pregnancies require surgical intervention

›Biliary colic most common biliary presentation in pregnancy

›Risk highest in second and third trimesters

›Imaging in pregnancy

›Ultrasound first-line

›No ionising radiation

›Safe in all trimesters

›Sensitivity >95% for gallstones maintained

›MRCP for suspected choledocholithiasis

›No ionising radiation preferred over CT

›Gadolinium contrast avoided in first trimester

›Safe in second and third trimester if necessary

›CT only if life-threatening alternative diagnosis not excludable

›Minimise fetal radiation exposure

›Benefit-risk discussion with patient and obstetrics

›Analgesia in pregnancy

›NSAIDs restrictions

›Avoid in first trimester (teratogenicity risk)

›Avoid in third trimester (premature ductus arteriosus closure)

›Second trimester with caution and limited duration

›Acetaminophen

›Safest analgesic in all trimesters

›1 g PO or IV every 6-8 hours

›First-line for mild to moderate biliary colic in pregnancy

›Opioids

›Morphine or hydromorphone with caution in second trimester

›Neonatal respiratory depression risk if used near delivery

›Short-course opioids acceptable for severe uncontrolled pain

›Surgical management in pregnancy

›Laparoscopic cholecystectomy safe in second trimester

›Preferred timing for elective surgery

›First trimester: organogenesis risk from anaesthesia

›Third trimester: technical difficulty, preterm labour risk

›Obstetrics consultation for all cases requiring intervention

›Fetal monitoring perioperatively

›Coordinate with hepatobiliary surgery

Geriatric

›Atypical presentation in elderly

›Presentation differences

›Reduced pain perception leads to underreporting

›Altered mental status may be sole presentation

›Afebrile despite active cholecystitis or cholangitis

›Delayed presentation common

›Complications more advanced at time of ED visit

›Higher in-hospital mortality for cholecystitis in elderly

›Murphy sign less reliable due to reduced pain perception

›Comorbidity considerations

›Polypharmacy interactions

›NSAIDs worsen renal function in elderly with CKD

›Avoid ketorolac if CrCl <30 ml/min

›Reduce ketorolac dose to 15 mg if age >65

›Anticoagulation and antiplatelet therapy

›Warfarin, DOACs, or antiplatelets require surgical bridging plan

›Consult haematology or surgery before intervention

›Surgical risk in elderly

›Higher perioperative risk

›Cardiorespiratory reserve reduced

›Frailty scoring (Clinical Frailty Scale) before elective surgery

›Percutaneous cholecystostomy as bridge to surgery in high-risk patients

›Conservative management threshold lower

›Some elderly patients managed non-operatively for acute cholecystitis

›Reassess goals of care and surgical candidacy

Pediatrics

›Epidemiology in children

›Prevalence

›Gallstones uncommon in children without predisposing conditions

›Haemolytic anaemia (sickle cell, spherocytosis) major paediatric risk factor

›Obesity-related gallstones increasing in adolescents

›Age distribution

›Infants and neonates: TPN-associated and haemolytic causes

›Adolescents: similar risk factor profile to adults with obesity

›Bile acid malabsorption in ileal disease (Crohn's)

›Clinical presentation in children

›Classic RUQ pain pattern

›Similar to adults in older children

›Younger children may present with non-specific abdominal pain

›Nausea and vomiting prominent in paediatric presentation

›Sickle cell disease considerations

›Pigment stones in up to 30% of sickle cell patients by adolescence

›RUQ pain may represent vaso-occlusive crisis vs biliary colic

›Ultrasound early to distinguish

›Analgesia in children

›Weight-based dosing

›Ketorolac 0.5 mg/kg IV (maximum 30 mg)

›Acetaminophen 15 mg/kg IV or PO (maximum 1 g)

›Morphine 0.1 mg/kg IV (maximum 10 mg) for severe pain

›Ondansetron for nausea

›0.15 mg/kg IV (maximum 4 mg)

›Weight-based dosing mandatory

›Surgical management in children

›Laparoscopic cholecystectomy safe and effective in children

›Standard technique with paediatric ports

›Paediatric surgery consultation for all cases

›Haemolytic disease management

›Elective cholecystectomy when stones confirmed symptomatic

›Haematology co-management for perioperative planning

10Background/b80

Epidemiology

›Prevalence and incidence

›Gallstone prevalence

›10-15% of US adults have gallstones

›Only 20% of gallstone carriers develop symptoms

›Biliary colic is the most common symptomatic manifestation of cholelithiasis

›Recurrence rates

›>90% of patients with first episode have recurrent pain within 10 years

›Two-thirds recur within 2 years

›Annual biliary event rate approximately 1-2% per year in asymptomatic stone carriers

›Demographics

›Sex distribution

›Female-to-male ratio approximately 2:1 before age 50

›Ratio equalises after menopause

›Female sex overall carries 2-3 times higher risk

›Ethnic variation

›Native American populations highest prevalence (Pima people up to 70%)

›Hispanic populations high risk

›African-American populations lower risk than non-Hispanic white

›Economic burden

›>750,000 cholecystectomies performed annually in the US

›Gallstone disease accounts for billions of dollars in annual healthcare costs

›ED visits for biliary colic number in the millions annually

Pathophysiology

›Stone formation mechanisms

›Cholesterol stone formation

›Requires cholesterol supersaturation of bile

›Gallbladder hypomotility allows nucleation

›Mucin hypersecretion promotes crystal growth

›Approximately 80% of gallstones in Western populations are cholesterol stones

›Pigment stone formation

›Black pigment stones from haemolysis (unconjugated bilirubin precipitation)

›Brown pigment stones from infection and biliary stasis

›Associated with haemolytic anaemia, cirrhosis, TPN

›Biliary colic mechanism

›Transient cystic duct obstruction

›Stone impaction at cystic duct or Hartmann's pouch

›Gallbladder contracts against obstruction

›Visceral pain via splanchnic nerve afferents

›Resolution mechanism

›Stone falls back into gallbladder lumen

›Cystic duct relaxation

›Pain resolves as obstruction clears

›Postprandial triggering

›Cholecystokinin (CCK) released by fatty meal

›CCK stimulates gallbladder contraction

›Contraction forces stone against duct orifice

›Stone types and CT visibility

›Calcified (calcite or calcium bilirubinate) stones

›Visible on CT in approximately 10-15% of cases

›High density on CT (>100 Hounsfield units)

›Cholesterol stones

›Predominantly invisible on CT

›Isodense with bile on non-contrast CT

›Ultrasound far superior for detection

Therapeutic Considerations

›NSAID mechanism in biliary colic

›Prostaglandin inhibition reduces gallbladder wall tension

›Prostaglandin E2 mediates gallbladder inflammation and contraction

›NSAIDs reduce ductal pressure and smooth muscle spasm

›Explain superiority over opioids and antispasmodics

›Evidence base

›Cochrane review: NSAIDs reduce pain and need for rescue analgesia

›NNT approximately 3 versus placebo

›May reduce progression to cholecystitis by reducing wall inflammation

›Surgical timing evidence

›Early vs delayed cholecystectomy for biliary colic

›Elective laparoscopic cholecystectomy safe and effective

›Same-admission cholecystectomy for gallstone pancreatitis reduces recurrence

›Urgent cholecystectomy for Grade I-II cholecystitis within 72 hours: reduced morbidity

›Non-surgical management limitations

›UDCA stone dissolution in <50% of ideal candidates

›High recurrence after UDCA cessation

›Extracorporeal shock wave lithotripsy no longer standard due to high recurrence

›Dietary modification evidence

›Low-fat diet

›Traditionally recommended but limited evidence supporting efficacy

›Cochrane 2024 review: modified fat diet not conclusively effective for symptom control

›Practical advice given nonetheless to reduce CCK stimulation

›Protective dietary factors

›Increased fruit and vegetable intake associated with lower gallstone risk

›Coffee consumption associated with reduced gallstone risk

›Rapid weight loss without UDCA prophylaxis increases stone formation risk

11Patient Discharge Instructions/pdi51

copy discharge instructions

›Diagnosis explanation

›You were seen today for biliary colic, caused by a gallstone temporarily blocking the tube from your gallbladder

›The pain typically occurs in the right upper abdomen or stomach area

›Episodes usually last between 1 and 5 hours then resolve on their own

›You have gallstones, which are hardened deposits that form in the gallbladder

›These are very common and affect about 1 in 10 adults

›The only definitive cure is surgical removal of the gallbladder (cholecystectomy)

›Return to emergency department immediately for

›Pain that lasts longer than 5-6 hours or gets significantly worse

›This may indicate your gallbladder is inflamed

›Do not wait until the next day

›Fever or chills

›Temperature above 38 C is a warning sign of infection

›This requires urgent evaluation

›Yellowing of skin or eyes (jaundice) or dark urine

›Suggests a stone is blocking the bile duct

›Requires urgent intervention

›Persistent vomiting preventing you from drinking fluids

›Risk of dehydration

›May require IV fluids

›Sudden worsening abdominal pain or a rigid abdomen

›Sign of a serious complication

›Call 911 or go to ED immediately

›Activity and diet instructions

›Diet modifications

›Avoid fatty or greasy foods until your gallbladder is removed

›Fatty meals trigger gallbladder contractions and can cause another attack

12References/r36

Guidelines and key sources

›Patel H, Jepsen J. Gallstone Disease: Common Questions and Answers. American Family Physician. 2024. PMID 38905549

›Comprehensive review of gallstone disease diagnosis and management

›Primary evidence source for natural history, recurrence rates, and POCUS performance

›Portincasa P, Moschetta A, Palasciano G. Cholesterol Gallstone Disease. Lancet. 2006. PMID 16844493

›Landmark review of cholesterol stone pathophysiology

›Risk factors, mechanisms of formation, and therapeutic targets

›Abraham S et al. Surgical and Nonsurgical Management of Gallstones. American Family Physician. 2014. PMID 24866215

›Evidence on UDCA, cholecystectomy timing, and non-surgical options

›Analgesia NNT data and dosing references

›Strasberg SM. Acute Calculous Cholecystitis. NEJM. 2008

›Tokyo Guidelines-aligned clinical management framework

›Surgical timing and complication management

›Fraquelli M et al. Non-Steroid Anti-Inflammatory Drugs for Biliary Colic. Cochrane Database of Systematic Reviews. 2016

›NSAID vs opioid and antispasmodic comparison

›NNT and evidence levels for analgesic choice

›Akhgar A et al. Efficacy of Intravenous Lidocaine vs Morphine in Biliary Colic. American Journal of Emergency Medicine. 2021. PMID 32595055

›IV lidocaine emerging analgesia data

›Faster onset at 10 minutes vs morphine

›Broder JS et al. GRACE-2: Low-Risk Recurrent Abdominal Pain in the Emergency Department. Academic Emergency Medicine. 2022

›Discharge criteria and risk stratification

›Society for Academic Emergency Medicine guidelines

›Ratanaprasatporn L et al. Multimodality Imaging in Gallbladder Disease. Radiographics. 2018. PMID 29320323

›CT and dual-energy CT performance for gallstones

›Imaging algorithm for biliary pathology

›Gallaher JR, Charles A. Acute Cholecystitis: A Review. JAMA. 2022

›Current management of cholecystitis complications

›Surgical urgency and Tokyo Guidelines grading

Evidence & Review