Acute pancreatitis resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Vidit Bhargava, M.B.B.S [2]; Vendhan Ramanujam M.B.B.S [3]

Overview

Acute pancreatitis is the acute inflammation of the pancreas.

Diagnostic Criteria

▸ Diagnosis is established by the presence of two of the three following criteria (strong recommendation, moderate quality of evidence):

• Abdominal pain consistent with acute pancreatitis (acute onset of a persistent, severe, epigastric pain often radiating to the back)
• Serum lipase or amylase ≥ 3 x ULN
• Characteristic findings on contrast-enhanced computed tomography (CECT), MRI, or transabdominal US

Causes

Life Threatening Causes

Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated. Acute pancreatitis is a life-threatening condition, especially if it progresses to necrotizing pancreatitis, and should be treated as such irrespective of the cause.

Common Causes

• Alcohol 30%

• Gallstones 35-40%

• Hypertriglyceridemia 1-4% cases

• Medication such as 5-mercaptopurine, azathioprine, 5-DDI

• Pancreatic tumor

• Post-ERCP

Management

Shown below is a diagram depicting the management of acute pancreatitis according to the American College of Gastroenterology (ACG).

Characterize the symptoms: ❑ Severe abdominal pain ❑ Breathing difficulty ❑ Nausea & vomiting ❑ Hiccups sometimes

Examine the patient: ❑ Fever ❑ Hypotension ❑ Cullen's sign ❑ Grey-Turner's sign ❑ Tachypnea ❑ Abdominal distension and/or tenderness

Consider alternative diagnosis: ❑ Gallstones ❑ Dissecting aortic aneurysm ❑ Pancreatic pseudocyst

❑ Assess hemodynamic stability

Stable

Unstable

Order Labs: (Urgent) ❑ CBC ❑ Hematocrit ❑ BUN ❑ Creatinine ❑ Amylase ❑ Lipase ❑ Triglyceride ❑ Total bilirubin ❑ Direct bilirubin ❑ Albumin ❑ AST ❑ ALT ❑ Alkaline phosphatase ❑ GGT ❑ Chest X-ray Order imaging studies: (Urgent) Trans abdominal USG (TAUSG)

Stabilize the patient

Diagnostic criteria: Any 2 out of 3 ❑ Abdominal pain consistent with disease ❑ Serum amylase or lipase values > 3 times normal ❑ Consistent findings from abdominal imaging

Acute Pancreatitis

Systemic inflammatory response syndrome? (Urgent)

Yes

No

Risk stratification for organ failure (Marshall scoring) (Urgent)

Lower risk

Higher risk

❑ Admit to medical ward

❑ Admit to ICU (Urgent)

Fluids: (Urgent) ❑ Aggressive hydration at 250-500 ml/hr with Ringer's lactate in first 12-24 hrs ❑ Reassess within 6 hrs after admission and for next 24-48 hrs Analgesics: (Urgent) ❑ Opioids are preferred ❑ Mepridine & morphine may be used as IV drips/pt. controlled analgesia Nutrition: (Urgent) ❑ Immediate oral feeding as soon as pain, vomiting, nausea subside

Fluids: (Urgent) ❑ Initiate with a fluid bolus ❑ Aggressive hydration at 250-500 ml/hr with Ringer's lactate in first 12-24 hrs ❑ Reassess within 6 hrs after admission and for next 24-48 hrs Analgesics: (Urgent) ❑ Opioids are preferred ❑ Mepridine & morphine may be used as IV drips/pt. controlled analgesia Nutrition: (Urgent) ❑ Nasogastric or nasojejunal feeding may be initiated once pain, vomiting, nausea subside ❑ Consider enteral feeding if above not tolerated

Cholangitis or biliary obstruction

Yes

❑ ERCP within 24 hrs/Cholecystectomy to prevent recurrence Click here for more details

No

❑ Consider MRCP/EUS

Clinical improvement within 48-72 hrs

Yes

❑ Assess for ability to maintain oral feeding at the end of 1 week

N o

❑ CECT/MRI

Recovery

Pancreatic necrosis

Failure to improve clinically after 7-10 days of hospitalization

Yes

❑ Supportive treatment

No

Suspected infected necrosis

❑ CT guided FNA ❑ Empiric antibiotics, necrosis penetrating: ❑ Meropenem 1g IV Q8h ❑ Ciprofloxacin 400mg IV Q12h plus metronidazole 500 mg IV Q8h for 14 days

Gram stain & Culture (-)

❑ Supportive treatment ❑ Consider repeat CT FNA every 7 days if no improvement

Gram stain & Culture(+)

Infected necrosis

Clinically stable

Clinically unstable

❑ Continue antibiotics & observe ❑ If asymptomatic no debridement, else consider surgical consultation

Prompt surgical consultation (Urgent)

ALT: Alanine aminotransferase; AST: Aspartate aminotransferase; BUN: Blood urea nitrogen; CBC: Complete blood count; CECT: Contrast-enhanced computed tomography; CT: Computed tomography; ERCP: Endoscopic retrograde cholangiopancreatography; EU: Endoscopic ultrasound; FNA: Fine-needle aspiration; GGT: Gamma-glutamyl transpeptidase; ICU: Intensive care unit; IV: Intravenous; MRCP: Magnetic resonance cholangiopancreatography; MRI: Magnetic resonance imaging; Q8h: Every 8 hours; Q12h: Every 12 hours

Modified Marshall Scoring System

Modified Marshall Scoring System^†

Organ System	0	1	2	3	4
Respiratory PaO2/FiO2	>400	301-400	201-300	101-200	≤101
Renal‡ Creatinine (μmol/l) Creatinine (mg/dl)	≤134 <1.4	134-169 1.4-1.8	170-310 1.9-3.6	311-439 3.6-4.9	>439 >4.9
Cardiovascular Systolic Blood Pressure (mmHg)	>90	<90, fluid responsive	<90, not fluid responsive	<90, pH <7.3	<90, pH <7.2

^† A score of 2 or more in any system defines the presence of organ failure.
^‡ A score for patients with pre-existing chronic renal failure depends on the extent of further deterioration of baseline renal function. No formal correction exists for a baseline creatinine ≥134 μmol/l or ≥1.4 mg/dl.

▸ For non-ventilated patients, the FiO2 can be estimated from below:

Supplemental oxygen (l/min)	FiO2 (%)
Room air	21
2	25
4	30
6–8	40
9–10	50

Grades of Severity

The definitions of severity in acute pancreatitis according to the revised Atlanta classification is as follows.

• Mild acute pancreatitis

▸ No organ failure

▸ No local or systemic complications

• Moderately severe acute pancreatitis

▸ Organ failure that resolves within 48 h (transient organ failure) and/or

▸ Local or systemic complications without persistent organ failure

• Severe acute pancreatitis

▸ Persistent organ failure (>48 h)

– Single organ failure

– Multiple organ failure

Do's

• CECT or MRI should be reserved for (strong recommendation, low quality of evidence):

• Patients who fail to improve clinically (e.g., persistent abdominal pain, fever, nausea, unable to begin oral intake) within the first 48-72 h after admission.
• Patients in whom the diagnosis is unclear.

• Perform abdominal USG in all patients (strong recommendation, low quality of evidence).
• Check serum triglycerides if stones/alcohol not an etiology, consider etiology if serum triglycerides >1000 mg/dl (conditional recommendation, moderate quality of evidence).
• Consider pancreatic tumor if age > 40 years (conditional recommendation, low quality of evidence).
• Limit endoscopic investigation in patients with acute idiopathic pancreatitis and refer them to centers of expertise (conditional recommendation, low quality of evidence).
• Assess hemodynamic status on presentation and begin resuscitative measures as needed (strong recommendation, moderate quality of evidence).
• Asses risk and stratify patients into higher and lower risk categories in order to assist triage (conditional recommendation, moderate quality of evidence).
• Admit patients with organ failure to intensive care unit (strong recommendation, low quality of evidence).
• Administer 250-500 ml/hour of aggressive hydration with isotonic crystalloid solution within the first 12-24 hours, unless cardiovascular and/or renal comorbidites exist (strong recommendation, moderate quality of evidence). Reassess fluid requirement frequently within 6 hours of admission and for the next 24-48 hours with the goal of decreasing blood urea nitrogen (strong recommendation, moderate quality of evidence).
• Administer a rapid bolus in patient's with hypotension and tachycardia (conditional recommendation, moderate quality of evidence).
• Use Ringer's Lactate(RL) as first choice agent, use normal saline if RL not available (conditional recommendation, moderate quality of evidence).
• Do ERCP within 24 hours of admission in patients with acute pancreatitis and concurrent acute cholangitis (strong recommendation, moderate quality of evidence). In its absence, MRCP or EUS should be used for screening choledocholithiasis if highly suspected (conditional recommendation, low quality of evidence).
• Do consider the diagnosis of gallstone pancreatitis in patients with previous history of biliary colic or gallbladder related symptoms, elevated ALT, elevated AST and gallstones detected during ultrasound and for further management, please click here.
• Pancreatic duct stents or post-procedure NSAID's are recommended to prevent post-ERCP pancreatitis (conditional recommendation, moderate quality of evidence).
• Antibiotics are given for extra-pancreatic infections such as cholangitis, catheter-acquired infections, bacteremia, UTI's, pneumonia (strong recommendation, high quality of evidence).
• Use antibiotics for infected necrosis, with high penetrance such as carbapenems, quinolones & metronidazole (conditional recommendation, low quality of evidence).
• Start oral feeding with a low fat solid diet or clear liquid diet if the abdominal pain has resolved and there is no nausea and vomiting in patients with mild acute pancreatitis (conditional recommendation, moderate quality of evidence).
• Start enteral nutrition (nasogastric and nasojejunal) in patients with severe acute pancreatitis and consider parenteral nutrition if enteral route is not available, not tolerated, or not meeting caloric requirements (strong recommendation, high quality of evidence).
• Perform elective cholecystectomy for gallstones to prevent recurrences (strong recommendation, moderate quality of evidence).
• Presence of asymptomatic pancreatic necrosis or asymptomatic pseudocysts do not warrant intervention, regardless of size, location, extension (strong recommendation, moderate quality of evidence).
• Minimally invasive necrosectomy which is preferred over open necrosectomy, radiological and/or endoscopic drainage should be delayed for more than 4 weeks (strong recommendation, low quality of evidence).

Dont's

• ERCP is not needed in most patients with gallstone pancreatitis, especially if they lack clinical or laboratory evidence of ongoing biliary obstruction.
• Do not shift patients with sepsis/organ failure to general ward.
• Do not perform emergency surgery, radiologic or endoscopic drainage in stable patients with infected necrosis, wait for 3-4 weeks for the development of a fibrous wall around the necrosis.
• Routine use of antibiotics as prophylaxis is not recommended in acute pancreatitis (strong recommendation, moderate quality of evidence).
• In patients with sterile necrosis, routine antibiotics are not recommended to prevent development of infected necrosis (strong recommendation, moderate quality of evidence).
• Anti-fungal agents are not recommended for prophylaxis or therapeutic use along with routine antibiotics (conditional recommendation, low quality of evidence).
• Do not do cholecystectomy until active inflammation subsides in necrotizing biliary pancreatitis in order to prevent infection (strong recommendation, moderate quality of evidence).