Quality Improvement Guidelines for Pediatric Abscess and Fluid Drainage

A Magnetic Resonance Imaging Protocol for the Evaluation of Pediatric Postappendectomy Abscess: A Quality Improvement Project

INTRODUCTION

Computed tomography (CT) scans are often used when cross-sectional imaging is required for evaluation of postappendectomy abscess, exposing children to a source of ionizing radiation. Our aim was to decrease the use of CT scans in pediatric postappendectomy patients by 50% in 12 mo and to sustain those results for 1 y.

METHODS

A comprehensive magnetic resonance imaging protocol was introduced in 2018 at a tertiary children's hospital within a general health system to replace CT scans in suspected pediatric postappendectomy abscess. Diagnostic and clinical outcomes were compared preprotocol (2015-2017) and postprotocol (2018-2022) implementation using standard univariate statistics. P < 0.05 was considered significant. Quality improvement methodology was used to design and implement the protocol.

RESULTS

Sixty eight pediatric postappendectomy patients received cross-sectional imaging during the study period. Overall, CT scans were used exclusively (100%, n = 27) in the preimplementation period compared to 31.7% (n = 13) of cross-sectional imaging in the postimplementation period. However, in the first year of protocol implementation, CT scan use only decreased to 78% of cross-sectional studies performed. The majority of protocol deviations (54%) also occurred in this time period. With improved education and reinforcement, CT scan utilization decreased to approximately 24% of cross-sectional studies annually. Missed abscess rate, time to diagnosis, drainage procedure type, readmission, and reoperation were similar between preimplementation and postimplementation periods.

CONCLUSIONS

Implementation of a postappendectomy abscess magnetic resonance imaging protocol was associated with decreased CT utilization in the pediatric population, while maintaining comparable diagnostic evaluation and clinical outcomes. Adherence to quality improvement principles facilitated achieving goals and sustaining gains.

Can magnetic resonance imaging replace computed tomography scans in the evaluation of pediatric post-appendectomy abscess?

BACKGROUND

Computed tomography scans have been used when cross-axial imaging is required to evaluate pediatric post-appendectomy abscesses. To reduce a source of radiation exposure, our institution converted to using contrast-enhanced magnetic resonance imaging to replace computed tomography scans in this clinical context. Our aim is to evaluate the performance of magnetic resonance imaging compared to computed tomography scans and associated clinical outcomes in this patient population.

METHODS

A contrast-enhanced comprehensive magnetic resonance imaging protocol was implemented to evaluate a post-appendectomy abscess in 2018. A retrospective chart review was performed from 2015 to 2022 for pediatric patients (<18 years old) with prior appendectomy and subsequent cross-sectional imaging to evaluate for an intraabdominal abscess. Patient characteristics and clinical parameters between the 2 modalities were abstracted and compared using standard univariate statistics.

RESULTS

There were a total of 72 post-appendectomy patients who received cross-axial imaging, which included 43 computed tomography scans and 29 magnetic resonance imaging during the study interval. Patient demographics were comparable between cohorts and rates of perforated appendicitis at the index operation (computed tomography: 79.1% vs magnetic resonance imaging: 86.2%). Missed abscess rate, abscess size, management technique, drainage culture results, readmission, and reoperation were similar between imaging modalities. Median request to scan time was longer for magnetic resonance imaging than computed tomography (191.5 vs 108 minutes, P = .04). The median duration of a comprehensive magnetic resonance imaging scan was 32 minutes (interquartile range 28-50.5 minutes).

CONCLUSION

Contrast-enhanced magnetic resonance imaging provides an alternative cross-sectional imaging modality to computed tomography scans to evaluate pediatric post-appendectomy abscesses.

Use of Tissue Plasminogen Activator in Abdominal Abscesses in Children-A Single-Center Randomized Control Trial

PURPOSE

To establish the efficacy of once-per-day intracavitary tissue plasminogen activator (tPA) in the treatment of pediatric intra-abdominal abscesses.

METHODS

A single-center prospective, double-blinded, randomized controlled trial of the use of intracavitary tPA in abdominal abscesses in children. Patients were randomized to either tPA-treatment or saline-treatment groups. Primary outcome was drainage catheter dwell (hours). Secondary outcomes were length of hospital stay, times to discharge, clinical and sonographic resolution, and adverse events (AEs).

RESULTS

Twenty-eight children were randomized to either group (n = 14 each). Demographics between groups were not significantly different (age P = .28; weight P = .40; gender P = .44). There were significantly more abscesses in the tPA-treated group (P = .03). Abscesses were secondary to perforated appendicitis (n = 25) or postappendectomy (n = 3). Thirty-four abscesses were drained, 4 aspirated, 3 neither drained/aspirated. There was no significant difference in number of drains (P = .14), drain size (P = .19), primary outcome (P = .077), or secondary outcomes found. No procedural or intervention drug-related AEs occurred. No patient in the saline-treated group required to be switched/treated with tPA.

CONCLUSION

No significant difference in the length of catheter dwell time, procedure time to discharge, or time to resolution was found. Intracavitary tPA was not associated with morbidity or mortality. The results neither support nor negate routine use of tPA in the drainage of intra-abdominal abscess in children. It is possible that a multicentre study with a larger number of patients may answer this question more definitively.

Basic Interventional Procedures: Practice Essentials

There has been an increasing demand in image-guided minimally invasive procedures and these have become an integral part of present-day clinical practice. Basic interventional radiology (IR) procedures have greatly reduced the need for invasive procedures for sampling as well as treating conditions like abscess and fluid collections. Owing to their minimally invasive nature, most of these procedures may be performed on the outpatient patients as daycare procedures. Some of these procedures in critically ill patients may be lifesaving. Basic interventional radiology (IR) procedures consist of image-guided fine-needle aspiration cytology and biopsy, tru-cut (core) biopsy, needle aspiration/drainage and percutaneous catheter drainage. This review aims to provide practice requisites for basic IR procedures.

Imaging of the pediatric peritoneum, mesentery and omentum

The normal peritoneal structures, including the mesenteries and the omenta, are only a few cell layers thick and are visible on imaging based upon the tissues (e.g., fat) and structures (e.g., blood vessels and lymph nodes) contained within them. These structures become more visible and change in appearance when involved by pathological processes. In this pictorial essay, we discuss the normal anatomy of the various abdominopelvic peritoneal structures and illustrate numerous developmental and acquired diagnoses that involve these structures in the pediatric and young adult population.

Preprocedural Coagulation Studies in Pediatric Patients Undergoing Percutaneous Intervention for Appendiceal Abscesses

The literature reports poor correlation between coagulation screening and prediction of bleeding risk in children. Our aim is to determine whether there is a role for coagulation studies in children undergoing percutaneous intervention for appendiceal abscesses. A retrospective review of 1805 patients presenting with a diagnosis of appendicitis from September 2008 to September 2013 was performed. Patients presenting with appendiceal abscess who underwent percutaneous intervention were selected for further review (n = 131). A total of 76 patients (58%) had normal coagulation studies, whereas 55 (42%) had elevated values. An international normalized ratio ≥ 1.3 was found in 26 patients. Patients with normal coagulation values had an incidence of bleeding of 1.3 per cent. In the abnormal coagulation group, 8 patients received fresh frozen plasma before intervention, whereas 47 did not. There was one hematoma noted in each group with an incidence of bleeding of 3.6 per cent. The overall incidence of hematoma was 2.3 per cent with no significant difference in bleeding risk between the normal and abnormal coagulation groups. In conclusion, although many patients are found to have elevated coagulation studies, most do not have bleeding complications after intervention. There is poor correlation between coagulation screening and postprocedural outcomes evidenced by the low risk of bleeding.

Intra-abdominal sepsis--epidemiology, aetiology and management

Peritonitis is a progressive disease leading inexorably from local peritoneal irritation to overwhelming sepsis and death unless this trajectory is interrupted by timely and effective therapy. In children peritonitis is usually secondary to intraperitoneal disease, the nature of which varies around the world. In rich countries, appendicitis is the principal cause whilst in poor countries diseases such as typhoid must be considered in the differential diagnosis. Where resources are limited, the clinical diagnosis of peritonitis mandates laparotomy for diagnosis and source control. In regions with unlimited resources, radiological investigation, ultrasound, CT scan or MRI may be used to select patients for non-operative management. For patients with appendicitis, laparoscopic surgery has achieved results comparable to open operation; however, in many centres open operation remains the standard. In complicated peritonitis "damage control surgery" may be appropriate wherein source control is undertaken as an emergency with definitive repair or reconstruction awaiting improvement in the patient's general condition. Awareness of abdominal compartment syndrome is essential. Primary peritonitis in rich countries is seen in high-risk groups, such as steroid-dependent nephrotic syndrome patients, whilst in poor countries the at-risk population is less well defined and the diagnosis is often made at surgery.