New concepts in the management of acute pancreatitis
Risk stratification
The goals of using risk stratification tools in AP are to identify patients at risk for developing major outcomes, including POF, infected pancreatic necrosis, and death, and to ensure timely triaging of patients to an appropriate level of care. Existing prediction models have only moderate predictive value.53,54 Examples include simple risk stratification tools such as blood urea nitrogen (BUN) and hemoconcentration,55,56 disease-modifying patient variables (age, obesity, etc.), biomarkers (i.e., angiopoietin 2),57 and more complex clinical scoring systems such as Acute Physiology and Chronic Health Evaluation II (APACHE II), BISAP (BUN, impaired mental status, SIRS criteria, age, pleural effusion) score, early warning system (EWS), Glasgow-Imrie score, Japanese severity score, and recently the Pancreatitis Activity Scoring System (PASS).58 Two recent guidelines affirmed the importance of predicting the severity of AP, using one or more predictive tools.1,2 The recent 2018 AGA technical review does not debate this commonsense approach, but does highlight that there is no published observational study or randomized, controlled trial (RCT) investigating whether prediction tools affect clinical outcomes.4
Recent advances in early treatment of AP
Literature review and definitions
The AP literature contains heterogeneous definitions of severe AP and of what constitutes a major outcome in AP. Based on definitions of the 2013 revised Atlanta Criteria, the 2018 AGA technical review and clinical guidelines emphasized precise definitions of primary outcomes of clinical importance in AP, including death, persistent single organ failure, or persistent multiple organ failure, each requiring a duration of more than 48 hours, and infected pancreatic or peripancreatic necrosis or both (Table 2).3,4
Pain management
Management of pain in AP is complex and requires a detailed discussion beyond the scope of this review, but recent clinical and translational studies raise questions about the current practice of using opioids for pain management in AP. A provocative, multicenter, retrospective cohort study reported lower 30-day mortality among critically ill patients who received epidural analgesia versus standard care without epidural analgesia.59 The possible mechanism of protection and the drugs administered are unclear. An interesting hypothesis is that the epidural cohort may have received lower exposure to morphine, which may increase gut permeability, the risk of infectious complications, and severity of AP, based on a translational study in mice.60
Intravenous fluid administration
Supportive care with the use of IV fluid hydration is a mainstay of treatment for AP in the first 12-24 hours. Table 3 summarizes the guidelines in regards to IV fluid administration as delineated by the ACG and AGA guidelines on the management of pancreatitis.1,3 Guidelines advocate for early fluid resuscitation to correct intravascular depletion in order to reduce morbidity and mortality associated with AP.1,2,4 The 2018 AGA guidelines endorse a conditional recommendation for using goal-directed therapy for initial fluid management,3 do not recommend for or against normal saline versus lactated Ringer’s (LR), but do advise against the use of hydroxyethyl starch fluids.3 Consistent with these recommendations, two recent RCTs published subsequent to the prespecified time periods of the AGA technical review and guideline, observed no significant differences between LR and normal saline on clinically meaningful outcomes.61,62 The AGA guidelines acknowledge that evidence was of very-low quality in support of goal-directed therapy,3,4 which has not been shown to have a significant reduction in persistent multiple organ failure, mortality, or pancreatic necrosis, compared with usual care. As the authors noted, interpretation of the data was limited by the absence of other critical outcomes in these trials (infected pancreatic necrosis), lack of uniformity of specific outcomes and definitions of transient and POF, few trials, and risk of bias. There is a clear need for a large RCT to provide evidence to guide decision making with fluid resuscitation in AP, particularly in regard to fluid type, volume, rate, duration, endpoints, and clinical outcomes.
