The impact of a rapid imaging protocol in acute cholecystitis-prospective cohort study

In this study we assess the impact of a "rapid imaging protocol" (RIP) on outcomes in patients with suspected acute cholecystitis (AC).

From January 2017 to January 2018, a prospective cohort study was implemented using a RIP with hepatoscintigraphy (HIDA) or CT scan (first available, goal within 4 h) in patients (n = 52) presenting with highly suspected AC and a clinical feature score of ≥1. For the latter, the following presenting features were scored as follows: 1 point for WBC count ≥10,000 (10⁹/L), 1.5 points for glucose ≥140 (mg/dl), and/or 1 point for age ≥50 yrs. The historical control was all patients admitted with suspected AC in a 1.5-year period (n = 117) under our previous "delayed imaging protocol" (DIP), which used US ± HIDA (post-admission) in select patients. Primary end points included: compare outcome and quality measures between the groups, evaluate diagnostic imaging performance for AC, and evaluate our proposed clinical feature score in the setting of AC.

Histopathologic features consistent with AC was more frequent in patients in the RIP (64% vs 39%, p = 0.008). The pooled positive predictive value of HIDA and CT scan for AC were 85% vs 94%, respectively. The RIP was associated with a significant reduction in time to surgery, length of stay, and conversions to open (p < 0.001, respectively). A clinical feature score of 3.5 predicted the likelihood of AC in 95% of the cases (x² for linear trend = 42, p < 0.001).

A protocol centered around rapid identification, defined clinical criteria (i.e. clinical feature score), and confirmation with non-user dependent imaging modalities has resulted in favorable outcomes. CT may be the study of choice when the likelihood of AC is high because it is superior at identifying severity.