Effect of delay in presentation on rate of perforation in children with appendicitis

Association of IgE-Mediated Allergy With Risk of Complicated Appendicitis in a Pediatric Population

IMPORTANCE

Childhood appendicitis is commonly complicated by gangrene and perforation, yet the causes of complicated appendicitis and how to avoid it remain unknown.

OBJECTIVE

To investigate whether children with IgE-mediated allergy have a lower risk of complicated appendicitis.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study included all consecutive patients younger than 15 years (hereinafter referred to as children) who underwent appendectomy for acute appendicitis at a tertiary pediatric surgery center in Sweden between January 1, 2007, through July 31, 2017. Children were stratified between those with and without IgE-mediated allergies.

MAIN OUTCOME AND MEASURES

Risk of complicated appendicitis with gangrene or perforation, with occurrence of IgE-mediated allergy as an independent variable and adjusted for age, sex, primary health care contacts, seasonal antigenic exposure, allergy medications, appendicolith, and duration of symptoms.

RESULTS

Of 605 included children (63.0% boys; median age, 10 years; interquartile range, 7-12 years), 102 (16.9%) had IgE-mediated allergy and 503 (83.1%) had no allergy. Complicated appendicitis occurred in 20 children with IgE-mediated allergy (19.6%) compared with 236 with no allergy (46.9%; adjusted odds ratio, 0.33; 95% CI, 0.18-0.59). No significant allergy effect modification by sex, seasonal antigenic exposure, or allergy medication was found. Children with IgE-mediated allergy had a shorter hospital stay (median, 2 days for both groups; interquartile range, 1-2 days vs 1-5 days; P = .004).

CONCLUSIONS AND RELEVANCE

In this study, children with IgE-mediated allergy had a lower risk of complicated appendicitis. The findings suggest that immunologic disposition modifies the clinical pattern of appendiceal disease. This theory introduces novel opportunities for understanding of the pathogenesis and clinical decision making for one of childhood's most common surgical emergencies.

Economic Analysis of Diagnostic Imaging in Pediatric Patients With Suspected Appendicitis

OBJECTIVE

The use of computed tomography (CT) and ultrasound (US) in patients with acute abdominal pain has substantial variation across pediatric emergency departments (EDs). This study compares the cost of diagnosing and treating suspected appendicitis across a multicenter network of children's hospitals.

METHODS

This study is a secondary analysis using deidentified data of a prospective, observational study of patients with suspected appendicitis at nine pediatric EDs. The study included patients 3 to 18 years old who presented to the ED with acute abdominal pain of <96 hours' duration.

RESULTS

Our data set contained 2,300 cases across nine sites. There was an appendicitis rate of 31.8% and perforation rate of 25.7%. Sites correctly diagnosed appendicitis in over 95% of cases. The negative appendicitis rate ranged from 2.5% to 4.7% while the missed appendicitis rate ranged from 0.3% to 1.1% with no significant differences in these rates across site. Across sites, we found a strong positive correlation (0.95) between CT rate and total cost per case and a strong negative correlation (-0.71) between US rate and cost. The cost per case at US sites was 5.2% ($367) less than at CT sites (p < 0.001). Similarly, costs per case at mixed sites were 3.4% ($244) less than at CT sites (p < 0.001). Comparing costs among CT sites or among US sites, the cost per case generally increased as the images per case increased among both CT sites and US sites, but the costs were universally higher at CT sites.

CONCLUSIONS

Our results provide support for US as the primary imaging modality for appendicitis. Sites that preferentially utilized US had lower costs per case than sites that primarily used CT. Imaging rates across sites varied due to practice patterns and resulted in a significant cost consequence without higher rates for negative appendectomies or missed appendicitis cases.

Time to appendectomy for acute appendicitis: A systematic review

OBJECTIVE

The goal of this systematic review by the American Pediatric Surgical Association Outcomes and Evidence-Based Practice Committee was to develop recommendations regarding time to appendectomy for acute appendicitis in children within the context of preventing adverse events, reducing cost, and optimizing patient/parent satisfaction.

METHODS

The committee selected three questions that were addressed by searching MEDLINE, Embase, and the Cochrane Library databases for English language articles published between January 1, 1970 and November 3, 2016. Consensus recommendations for each question were made based on the best available evidence for both children and adults.

RESULTS

Based on level 3-4 evidence, appendectomy performed within 24h of admission in patients with acute appendicitis does not appear to be associated with increased perforation rates or other adverse events. Based on level 4 evidence, time from admission to appendectomy within 24h does not increase hospital cost or length of stay (LOS). Data are currently limited to determine an association between the timing of appendectomy and parent/patient satisfaction.

CONCLUSIONS

There is a paucity of high-quality evidence in the literature regarding timing of appendectomy for patients with acute appendicitis and its association with adverse events or resource utilization. Based on available evidence, appendectomy performed within the first 24h from presentation is not associated with an increased risk of perforation or adverse outcomes.

TYPE OF STUDY

Systematic Review of Level 1-4 studies.

Influence of Time to Appendectomy and Operative Duration on Hospital Cost in Children with Uncomplicated Appendicitis

BACKGROUND

The goal of this study was to examine the influence of time to appendectomy (TTA) and operative duration (OD) on hospital cost as surrogate measures of perioperative efficiency.

STUDY DESIGN

We conducted a retrospective cohort analysis of 2,116 children undergoing appendectomy for uncomplicated appendicitis at 16 children's hospitals from January 2013 to December 2014. Time to appendectomy (emergency department presentation to incision) and OD were obtained from the NSQIP Pediatric Appendectomy Pilot Database and merged with cost data from the Pediatric Health Information System Database. Multivariate regression was used to examine the influence of TTA and OD (categorized by quartiles of hospital-level means) on hospital cost, adjusting for patient and hospital-level characteristics.

RESULTS

Median TTA and OD across all patients was 7.3 hours (interquartile range 4.4 to 12.4 hours) and 36 minutes (interquartile range 26 to 49 minutes), respectively. The longest quartile of OD was associated with 38% higher total cost ($2,512/case; rate ratio [RR] 1.38; 95% CI 1.27 to 1.5; p < 0.001) and 27% higher operating room-associated cost ($960/case; RR 1.27; 95% CI 1.22 to 1.34; p < 0.001) compared with the shortest quartile. The longest quartile of TTA was associated with 23% higher total cost ($1,589/case; RR 1.23; 95% CI 1.14 to 1.32; p < 0.001) and 53% higher room-associated cost ($906/case; RR 1.53; 95% CI 1.35 to 1.74; p < 0.001) compared with the shortest quartile. The influence of TTA and OD were independent but potentiating effects, with median cost for hospitals in both the longest quartiles of TTA and OD being 79% higher than those in the shortest quartiles.

CONCLUSIONS

Longer TTA and OD were independently associated with increased hospital cost, with OD being the most significant driver of cost variation across hospitals. Identification of best practices from high-efficiency hospitals might provide a high-yield strategy for improving value in appendicitis care.

Accuracy of low dose CT in the diagnosis of appendicitis in childhood and comparison with USG and standard dose CT

OBJECTIVES

Computed tomography should be performed after careful consideration due to radiation hazard, which is why interest in low dose CT has increased recently in acute appendicitis. Previous studies have been performed in adult and adolescents populations, but no studies have reported on the efficacy of using low-dose CT in children younger than 10 years.

METHODS

Patients (n=475) younger than 10 years who were examined for acute appendicitis were recruited. Subjects were divided into three groups according to the examinations performed: low-dose CT, ultrasonography, and standard-dose CT. Subjects were categorized according to age and body mass index (BMI).

RESULTS

Low-dose CT was a contributive tool in diagnosing appendicitis, and it was an adequate method, when compared with ultrasonography and standard-dose CT in terms of sensitivity (95.5% vs. 95.0% and 94.5%, p=0.794), specificity (94.9% vs. 80.0% and 98.8%, p=0.024), positive-predictive value (96.4% vs. 92.7% and 97.2%, p=0.019), and negative-predictive value (93.7% vs. 85.7% and 91.3%, p=0.890). Low-dose CT accurately diagnosed patients with a perforated appendix. Acute appendicitis was effectively diagnosed using low-dose CT in both early and middle childhood. BMI did not influence the accuracy of detecting acute appendicitis on low-dose CT.

CONCLUSION

Low-dose CT is effective and accurate for diagnosing acute appendicitis in childhood, as well as in adolescents and young adults. Additionally, low-dose CT was relatively accurate, irrespective of age or BMI, for detecting acute appendicitis. Therefore, low-dose CT is recommended for assessing children with suspected acute appendicitis.

Evaluating the risk of appendiceal perforation when using ultrasound as the initial diagnostic imaging modality in children with suspected appendicitis

BACKGROUND

Ultrasound scan has gained attention for diagnosing appendicitis due to its avoidance of ionizing radiation. However, studies show that ultrasound scan carries inferior sensitivity to computed tomography scan. A non-diagnostic ultrasound scan could increase the time to diagnosis and appendicectomy, particularly if follow-up computed tomography scan is needed. Some studies suggest that delaying appendicectomy increases the risk of perforation.

OBJECTIVE

To investigate the risk of appendiceal perforation when using ultrasound scan as the initial diagnostic imaging modality in children with suspected appendicitis.

METHODS

We retrospectively reviewed 1411 charts of children ≤17 years old diagnosed with appendicitis at two urban academic medical centers. Patients who underwent ultrasound scan first were compared to those who underwent computed tomography scan first. In the sub-group analysis, patients who only received ultrasound scan were compared to those who received initial ultrasound scan followed by computed tomography scan. Main outcome measures were appendiceal perforation rate and time from triage to appendicectomy.

RESULTS

In 720 children eligible for analysis, there was no significant difference in perforation rate between those who had initial ultrasound scan and those who had initial computed tomography scan (7.3% vs. 8.9%, p = 0.44), nor in those who had ultrasound scan only and those who had initial ultrasound scan followed by computed tomography scan (8.0% vs. 5.6%, p = 0.42). Those patients who had ultrasound scan first had a shorter triage-to-incision time than those who had computed tomography scan first (9.2 (IQR: 5.9, 14.0) vs. 10.2 (IQR: 7.3, 14.3) hours, p = 0.03), whereas those who had ultrasound scan followed by computed tomography scan took longer than those who had ultrasound scan only (7.8 (IQR: 5.3, 11.6) vs. 15.1 (IQR: 10.6, 20.6), p < 0.001). Children < 12 years old receiving ultrasound scan first had lower perforation rate (p = 0.01) and shorter triage-to-incision time (p = 0.003).

CONCLUSION

Children with suspected appendicitis receiving ultrasound scan as the initial diagnostic imaging modality do not have increased risk of perforation compared to those receiving computed tomography scan first. We recommend that children <12 years of age receive ultrasound scan first.

Time to Appendectomy and Risk of Complicated Appendicitis and Adverse Outcomes in Children

IMPORTANCE

Management of appendicitis as an urgent rather than emergency procedure has become an increasingly common practice in children. Controversy remains as to whether this practice is associated with increased risk of complicated appendicitis and adverse events.

OBJECTIVE

To examine the association between time to appendectomy (TTA) and risk of complicated appendicitis and postoperative complications.

DESIGN, SETTING, AND PARTICIPANTS

In this retrospective cohort study using the Pediatric National Surgical Quality Improvement Program appendectomy pilot database, 2429 children younger than 18 years who underwent appendectomy within 24 hours of presentation at 23 children's hospitals from January 1, 2013, through December 31, 2014, were studied.

EXPOSURES

The main exposure was TTA, defined as the time from emergency department presentation to appendectomy. Patients were further categorized into early and late TTA groups based on whether their TTA was shorter or longer than their hospital's median TTA. Exposures were defined in this manner to compare rates of complicated appendicitis within a time frame sensitive to each hospital's existing infrastructure and diagnostic practices.

MAIN OUTCOMES AND MEASURES

The primary outcome was complicated appendicitis documented at operation. The association between treatment delay and complicated appendicitis was examined across all hospitals by using TTA as a continuous variable and at the level of individual hospitals by using TTA as a categorical variable comparing outcomes between late and early TTA groups. Secondary outcomes included length of stay (LOS) and postoperative complications (incisional and organ space infections, percutaneous drainage procedures, unplanned reoperation, and hospital revisits).

RESULTS

Of the 6767 patients who met the inclusion criteria, 2429 were included in the analysis (median age, 10 years; interquartile range, 8-13 years; 1467 [60.4%] male). Median hospital TTA was 7.4 hours (range, 5.0-19.2 hours), and 574 patients (23.6%) were diagnosed with complicated appendicitis (range, 5.2%-51.1% across hospitals). In multivariable analyses, increasing TTA was not associated with risk of complicated appendicitis (odds ratio per 1-hour increase in TTA, 0.99; 95% CI, 0.97-1.02). The odds ratios of complicated appendicitis for late vs early TTA across hospitals ranged from 0.39 to 9.63, and only 1 of the 23 hospitals had a statistically significant increase in their late TTA group (odds ratio, 9.63; 95% CI, 1.08-86.17; P = .03). Increasing TTA was associated with longer LOS (increase in mean LOS for each additional hour of TTA, 0.06 days; 95% CI, 0.03-0.08 days; P < .001) but was not associated with increased risk of any of the other secondary outcomes.

CONCLUSIONS AND RELEVANCE

Delay of appendectomy within 24 hours of presentation was not associated with increased risk of complicated appendicitis or adverse outcomes. These results support the premise that appendectomy can be safely performed as an urgent rather than emergency procedure.

Acute appendicitis in children: can surgery be postponed? Short-term results in a cohort of 225 children

PURPOSE

To our knowledge, there is no German study, which has examined the relationship between a postponement of surgery (from emergency service to standard working time) and the corresponding risk of postoperative complications in children and adolescents with acute appendicitis. The aim of this study is to examine if surgery of acute appendicitis in childhood can be postponed from night shift to the next working day without negative effects for the patient.

METHODS

In a retrospective analysis (September 2001 to June 2007), the files of 225 paediatric surgical patients with acute appendicitis have been analysed concerning history, histology, course of treatment and development of complications. The cohort was divided into groups by their histology (common, "A", complicated appendicitis, "B") and by the median time (10 h) from admission to surgery (immediate, "C", delayed surgery, "D"). These groups have been analysed and compared.

RESULTS

Groups A and B did not differ concerning time to admittance (p = 0.922). Seven patients developed complications (n = 7/225, 3.1%). Six complications were seen in group C (n = 6/113, 5.3%) compared to 1 in group D (n = 1/112, 0.9%), the difference was not significant (p = 0.119). None of the patients of group B developed complications after delayed surgery. Median follow-up was 10 days (IQR 7-15).

CONCLUSIONS

In view of the development of complications, there was no evidence that the time between inpatient admission and surgery had any impact on the postoperative result. Thus, there is usually no need to perform surgery in common appendicitis during night shift.

Diagnostic Accuracy of History, Physical Examination, Laboratory Tests, and Point-of-care Ultrasound for Pediatric Acute Appendicitis in the Emergency Department: A Systematic Review and Meta-analysis

BACKGROUND

Acute appendicitis (AA) is the most common surgical emergency in children. Accurate and timely diagnosis is crucial but challenging due to atypical presentations and the inherent difficulty of obtaining a reliable history and physical examination in younger children.

OBJECTIVES

The aim of this study was to determine the utility of history, physical examination, laboratory tests, Pediatric Appendicitis Score (PAS) and Emergency Department Point-of-Care Ultrasound (ED-POCUS) in the diagnosis of AA in ED pediatric patients. We performed a systematic review and meta-analysis and used a test-treatment threshold model to identify diagnostic findings that could rule in/out AA and obviate the need for further imaging studies, specifically computed tomography (CT) scan, magnetic resonance imaging (MRI), and radiology department ultrasound (RUS).

METHODS

We searched PubMed, EMBASE, and SCOPUS up to October 2016 for studies on ED pediatric patients with abdominal pain. Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS-2) was used to evaluate the quality and applicability of included studies. Positive and negative likelihood ratios (LR+ and LR-) for diagnostic modalities were calculated and when appropriate data was pooled using Meta-DiSc. Based on the available literature on the test characteristics of different imaging modalities and applying the Pauker-Kassirer method we developed a test-treatment threshold model.

RESULTS

Twenty-one studies were included encompassing 8,605 patients with weighted AA prevalence of 39.2%. Studies had variable quality using the QUADAS-2 tool with most studies at high risk of partial verification bias. We divided studies based on their inclusion criteria into two groups of "undifferentiated abdominal pain" and abdominal pain "suspected of AA." In patients with undifferentiated abdominal pain, history of "pain migration to right lower quadrant (RLQ)" (LR+ = 4.81, 95% confidence interval [CI] = 3.59-6.44) and presence of "cough/hop pain" in the physical examination (LR+ = 7.64, 95% CI = 5.94-9.83) were most strongly associated with AA. In patients suspected of AA none of the history or laboratory findings were strongly associated with AA. Rovsing's sign was the physical examination finding most strongly associated with AA (LR+ = 3.52, 95% CI = 2.65-4.68). Among different PAS cutoff points, PAS ≥ 9 (LR+ = 5.26, 95% CI = 3.34-8.29) was most associated with AA. None of the history, physical examination, laboratory tests findings, or PAS alone could rule in or rule out AA in patients with undifferentiated abdominal pain or those suspected of AA. ED-POCUS had LR+ of 9.24 (95% CI = 6.24-13.28) and LR- of 0.17 (95% CI = 0.09-0.30). Using our test-treatment threshold model, positive ED-POCUS could rule in AA without the use of CT and MRI, but negative ED-POCUS could not rule out AA.

CONCLUSION

Presence of AA is more likely in patients with undifferentiated abdominal pain migrating to the RLQ or when cough/hop pain is present in the physical examination. Once AA is suspected, no single history, physical examination, laboratory finding, or score attained on PAS can eliminate the need for imaging studies. Operating characteristics of ED-POCUS are similar to those reported for RUS in literature for diagnosis of AA. In ED patients suspected of AA, a positive ED-POCUS is diagnostic and obviates the need for CT or MRI while negative ED-POCUS is not enough to rule out AA.

The Role of Doctors and Patients in Appendicitis Perforation

In this study, we aimed to determine factors that cause appendix perforations and to identify the role of physicians and patients in contributing to the cause of these perforations. This study was conducted between April 2010 and May 2015 and included 64 patients with perforated appendicitis. Patients’ medical records were examined for factors that might have contributed to perforation, and the roles of patients and physicians in perforation appendicitis were evaluated. The perforation rate of patients with appendicitis was 16.0 per cent. The average duration from symptom onset to hospital admission was 4.4 days (29 patients were admitted to hospital within two days, 35 were admitted later). In total, 38 patients had visited a different hospital before admission. Furthermore, six out of 26 patients who had not visited any other hospital had consumed analgesics. Factors contributing to appendix perforation included misdiagnosis at the patient's initial visit (56.0%), delayed admission to hospital (11.0%), and use of analgesics (9.0%). The cause of perforation was mostly physician-related in children and adults, and patient-related in older adults.

Malpractice in Cases of Pediatric Appendicitis

Appendicitis is one of the most common diagnoses in children and is frequently the focus of alleged malpractice. Causes for medical malpractice claims and outcomes of disputes in pediatric patients with appendicitis are currently unknown. A retrospective database review of all medical malpractice claims concerning the diagnosis of appendicitis from 1984 to 2013 in pediatric patients was performed. Alleged claims, causes of malpractice, and outcomes were recorded and analyzed. Of the 203 included cases, failure or delays in diagnosing appendicitis are the most common causes of malpractice lawsuits and account for the majority of the largest payments to plaintiffs outcomes. Cases that ultimately went to trial resulted in defense verdicts in 67.5%. Mortality occurred in 19.9% of included cases. Timely diagnosis of appendicitis in children should be the focus of physicians across all specialties to improve patient safety and potentially reduce medicolegal liability.

Current Approach to the Diagnosis and Emergency Department Management of Appendicitis in Children

Concerns about radiation exposure have led to a decrease in the use of computed tomography in suspected appendicitis, with increased reliance on ultrasound. Children with suspected appendicitis should be risk stratified using a combination of clinical signs and symptoms, white blood cell count, and ultrasound in order to guide further evaluation and management. Magnetic resonance imaging is a promising imaging modality but remains costly. Ongoing research is evaluating the role of nonoperative management in children with confirmed appendicitis.

Time-of-day and appendicitis: Impact on management and outcomes

BACKGROUND

Observational research has shown that delayed presentation is associated with perforation in appendicitis. Many factors that affect the ability to present for evaluation are influenced by time of day (eg, child care, work, transportation, and office hours of primary care settings). Our objective was to evaluate for an association between care processes or clinical outcomes and presentation time of day.

METHODS

The study evaluated a prospective cohort of 7,548 adults undergoing appendectomy at 56 hospitals across Washington State. Relative to presentation time, patient characteristics, time to operation, imaging use, negative appendectomy, and perforation were compared using univariate and multivariate methodologies.

RESULTS

Overall, 63% of patients presented between noon and midnight. More men presented in the morning; however, race, insurance status, comorbid conditions, and white blood cell count did not differ by presentation time. Daytime presenters (6 am to 6 pm) were less likely to undergo imaging (94% vs 98%, P < .05) and had a nearly 50% decrease in median preoperative time (6.0 h vs 8.7 h, P < .001). Perforation significantly differed by time-of-day. Patients who presented during the workday (9 am to 3 pm) had a 30% increase in odds of perforation compared with patients presenting in the early morning/late night (adjusted odds ratio 1.29, 95% confidence interval, 1.05-1.59). Negative appendectomy did not vary by time-of-day.

CONCLUSION

Most patients with appendicitis presented in the afternoon/evening. Socioeconomic characteristics did not vary with time-of-presentation. Patients who presented during the workday more often had perforated appendicitis compared with those who presented early morning or late night. Processes of care differed (both time-to-operation and imaging use). Time-of-day is associated with patient outcomes, process of care, and decisions to present for evaluation; this association has implications for the planning of the surgical workforce and efforts directed at quality improvement.

Paradigm Shifts in the Treatment of Appendicitis

Acute appendicitis is the most common cause of emergent surgery in children. Historically, surgical dogma dictated emergent appendectomy due to concern for impending perforation. Recently, however, there has been a paradigm shift in both the understanding of its pathophysiology as well as its treatment to more nonoperative management. No longer is it considered a spectrum from uncomplicated appendicitis inevitably progressing to complicated appendicitis over time. Rather, uncomplicated and complicated appendicitis are now considered two distinct pathophysiologic entities. This change requires not only educating the patients and their families but also the general practitioners who will be managing treatment expectations and caring for patients long term. In this article, we review the pathophysiology of appendicitis, including the differentiation between uncomplicated and complicated appendicitis, as well as the new treatment paradigms. [Pediatr Ann. 2016;45(7):e235-e240.].

Evaluating the effect of time process measures on appendectomy clinical outcomes

BACKGROUND

With varied reports on the impact of time to appendectomy on clinical outcomes, we examined the effects of pre-operative delays in pediatric acute appendicitis.

METHODS

Children with acute appendicitis (January 2013-June 2014) were identified from a prospective database. Univariate analyses compared time metrics, patient characteristics, and disease severity with postoperative complications (POC) and organ space surgical site infection (OSSI), and multivariate logistic regression determined predictors of POC and OSSI.

RESULTS

1211 patients underwent appendectomy. Median age was 10.4years (IQR 7.8-13years). 537 patients (45%) had complex appendicitis. Overall, POC was 11% (n=133), and OSSI was 9% (n=105). Neither time from presentation to appendectomy nor diagnosis to appendectomy increased POCs. On univariate analyses, operative time (OT) was longer in patients with POC (57min (IQR 49-75) vs. 46min (IQR 36-57), p<0.001 and OSSI (60min (IQR 51-80) vs. 46min (IQR 37-57), p<0.001. However, after adjusting for confounding factors, disease severity remained the most significant predictor of POC (OR 6.5, 95% CI 2.79-15.23) and OSSI (OR 76.6, 95% CI 7.87-745.65).

CONCLUSION

Pre-operative delays were not associated with increased POC or OSSI. The strongest predictor of POC or OSSI was disease severity, for which operative time may represent a surrogate.

Appendicitis in the Infant Population: A Case Report and Review of a Four-Month Old With Appendicitis

BACKGROUND

Appendicitis is uncommon in children <6 months old, with few observational studies reporting cases of children younger than 5 years old with the diagnosis. The classic periumbilical pain that migrates to the right lower quadrant, followed by the onset of fever and vomiting, is present in approximately 40% of pediatric patients under 12 years of age with appendicitis.

CASE REPORT

A 4-month-old girl presented to the Emergency Department (ED) with acute onset of grunting, pallor, fussiness, emesis, and diarrhea. The patient was initially afebrile, tachycardic, and tachypneic with a soft, nondistended, nontender abdomen and active bowel sounds. The patient became febrile, with a maximum temperature of 39.3°C (102.7°F), and remained tachycardic despite receiving fluids and antipyretics. Laboratory studies were notable for mild dehydration and sterile pyuria. Chest x-ray study was negative for infectious etiologies. Initial abdominal ultrasound found no clear etiology of the patient's symptoms. The patient was admitted to inpatient pediatrics for dehydration, fever, and presumed pyelonephritis. Twenty-four hours later the patient's abdomen became distended and diffusely tender to palpation, with obstipation and increasing episodes of emesis. Abdominal x-ray study demonstrated mild gaseous distension of multiple bowel loops with repeat abdominal ultrasound notable for a focal 8-mm, noncompressible hyperemic structure in the right lower quadrant. The patient was taken to the operating room for a laparoscopic appendectomy. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Appendicitis is a potentially life-threatening condition. In the infant population it frequently presents without the features typically seen in older children.

Are appendectomy outcomes in level I trauma centers as good as we think?

BACKGROUND

Designated trauma centers improve outcomes for severely injured patients. However, major trauma workload can disrupt other care pathways and some patient groups may compete ineffectively for resources with higher priority trauma cases. This study tested the hypothesis that treatment at a higher-level trauma center is an independent predictor for worse outcome after appendectomy.

METHODS

An observational study was undertaken using an all-payer longitudinal data set (California State Inpatient Database 2007-2011). All patients with an ICD-90-CM diagnosis of "acute appendicitis" (International Classification of Diseases, Ninth Revision, Clinical Modification code 540) that subsequently underwent appendectomy were included. Patients transferred between hospitals were excluded to minimize selection bias. The outcome measures were days to the operating room, length of stay, unplanned 30-d readmission (to any hospital in California), and in-hospital mortality. Logistic and generalized linear regression models were used to adjust for patient- (age, sex, payer status, race, Charlson comorbidity index, weekend admission, and generalized peritonitis) and hospital-level (teaching status and bed size) factors.

RESULTS

There were 119,601 patients treated in 278 individual hospitals. Patients in level I trauma centers (L1TCs) reached the operating room later (predicted mean difference 0.25 d [95% confidence interval 0.14-0.36]), stayed in hospital longer (0.83 d [0.36-1.31]), and had higher adjusted odds of generalized peritonitis (odds ratio 1.63 [95% confidence interval 1.13-2.36]) than those in nontrauma centers. There were no differences in mortality or unplanned 30-d readmissions to hospital; or between level II trauma centers and nontrauma centers across any of the measured outcomes.

CONCLUSIONS

Odds of generalized peritonitis are higher and hospital length of stay is longer in L1TCs, although we found no evidence that patients come to serious harm in such institutions. Further work is necessary to determine whether pressure for resources in L1TCs can explain these findings.

Nonoperative treatment of acute appendicitis in children: A feasibility study

PURPOSE

Nonoperative treatment of acute appendicitis appears to be feasible in adults. It is unclear whether the same is true for children.

METHODS

Children 5-18 years with <48 h symptoms of acute appendicitis were offered nonoperative treatment: 2 doses of piperacillin IV, then ampicillin/clavulanate ×1 week. Treatment failure (worsening on therapy) and recurrence (after completion of therapy) were noted. Patients who declined enrollment were asked to participate as controls. Cost-utility analysis was performed using Pediatric Quality of Life Scale (PedsQL®) to calculate quality-adjusted life month (QALM) for study and control patients.

RESULTS

Twenty-four patients agreed to undergo nonoperative management, and 50 acted as controls. At a mean follow-up of 14 months, three of the 24 failed on therapy, and 2/21 returned with recurrent appendicitis at 43 and 52 days, respectively. Two patients elected to undergo an interval appendectomy despite absence of symptoms. Appendectomy-free rate at one year was therefore 71% (C.I. 50-87%). No patient developed perforation or other complications. Cost-utility analysis shows a 0.007-0.03 QALM increase and a $1359 savings from $4130 to $2771 per nonoperatively treated patient.

CONCLUSION

Despite occasional late recurrences, antibiotic-only treatment of early appendicitis in children is feasible, safe, cost-effective and is experienced more favorably by patients and parents.

Patient-centered outcomes research in appendicitis in children: Bridging the knowledge gap

PURPOSE

Patient-centered outcomes research (PCOR) aims to give patients a better understanding of the treatment options to enable optimal decision-making. As nonoperative alternatives are now being evaluated in children for acute appendicitis, we surveyed patients and their families regarding their knowledge of appendicitis and evaluated whether providing basic medical information would affect their perception of the disease and allow them to more rationally consider the treatment alternatives.

METHODS

Families of children aged 5-18 presenting to the Emergency Department with suspected appendicitis were recruited for a tablet-based interactive educational survey. One hundred subjects (caregivers and patients ≥ 15 years) were questioned before and after an education session about their understanding of appendicitis, including questions on three hypothetical treatment options: urgent appendectomy, antibiotics alone, or initial antibiotics followed by elective appendectomy. Subjects were clearly informed that urgent appendectomy is currently the standard of care.

RESULTS

Only 14% of respondents correctly identified the mortality rate of appendicitis (17 deaths/year according to the 2010 US census) when compared with other extremely rare causes of death. Fifty-four and 31% thought it was more common than death from lightning (40/year) and hunting-associated deaths (44/year), respectively. Eighty-two percent of respondents believed it "likely" or "very likely" that the appendix would rupture if operation was at all delayed, and 81% believed that rupture of the appendix would rapidly lead to severe complications and death. In univariate analysis, this perception was significantly more prevalent for mothers (odds ratio, (OR) 5.19, confidence interval (CI) 1.33-21.15), and subjects who knew at least one friend or relative who had a negative experience with appendicitis (OR 5.53, CI 1.40-25.47). Following education, these perceptions changed significantly (53% still believed that immediate operation was necessary, and 47% believed perforation led to great morbidity and potential mortality, P<0.001). In a survey of potential appendicitis treatment options, urgent appendectomy was considered a "good" or "very good" option by 74% of subjects, compared with 68% for antibiotics only without appendectomy and 49% for initial antibiotic therapy followed by elective outpatient appendectomy.

CONCLUSION

There was a striking knowledge gap in the participant perception of appendicitis. Appropriate education can correct anecdotally supported misconceptions. Adequate education may empower patients to make better-informed decisions about their medical care and may be important for future studies in alternative treatments for appendicitis in children.

Effects of Timing to Diagnosis and Appendectomy in Pediatric Appendicitis

OBJECTIVES

Prospectively follow pediatric appendicitis patients to assess outcomes and rates of appendiceal perforations relative to duration of symptomatology and appendectomy timing.

METHODS

Data were collected on the duration of symptomatology to diagnosis and from diagnosis to appendectomy. Symptomatology duration was evaluated in 24-hour increments, and diagnosis to appendectomy was evaluated in 3-hour intervals. Appendiceal perforation rates, hospital length of stay (LOS), and operating room (OR) times were evaluated.

RESULTS

Data were analyzed on 230 patients. Average age was 9.3 years (±3.2), 93 (40%) were female, and 64 (28%) appendectomies were perforated. Perforations had a mean 10 minutes longer OR time (63 vs 50 minutes, P < 0.001) and a 57% increase in hospital LOS (3 days' interquartile range, 1-5 vs 1 day's interquartile range, 1-3; P < 0.001). From diagnosis to appendectomy, those taken 0 to 3 hours, 4 to 6 hours, or longer than 6 hours after diagnosis had no statistically significant difference in hospital LOS or perforation rates and no clinically significant difference in OR times. Symptomatology greater than 48 hours had hospital LOS 55.7% greater and 4.9 times increased odds for perforation than those 0 to 23 hours (P < 0.05).We found no effect on perforation rates, hospital LOS, or OR time when symptomatology duration was compared independently with timing of surgery.

CONCLUSIONS

Pediatric patients with appendicitis presenting with greater than 48 hours of symptomatology had 4.9 times increased odds of perforation and 56% greater hospital LOS than those presenting within 0 to 23 hours. We were unable to demonstrate a difference in perforation rates based on emergency department LOS before surgery.

Pediatric patients transferred for operative management of appendicitis: are they at a disadvantage?

PURPOSE

Many pediatric patients are initially diagnosed with appendicitis at referring hospitals and are subsequently transferred to pediatric facilities. We aimed to compare outcomes of patients transferred to a pediatric referral center to those who present primarily for operative management of appendicitis.

METHODS

A retrospective review of 326 patients with operative appendicitis from July 2012 to July 2013 was performed. Demographic data, clinical parameters, and outcomes were analyzed.

RESULTS

Transferred (n=222, 68%) and primary patients (n=104, 32%) were similar except for mean age (primary 12.4 vs. transferred 11.2 years, p<0.01). Computed tomography scans were performed in 80% of transferred compared to 40% of primary patients. Primary patients were more likely to present between the hours of 09:00 and 17:59 (52%), while transferred arrived equally across all hours. Both groups were more likely to present with acute appendicitis (primary 56% vs. transfer 61%, p=NS). There was no difference in time of diagnosis to time of appendectomy, length of hospital stay, or 30 day complications (primary 8.6% vs. transfer 5.8%, p=NS).

CONCLUSIONS

Patients transferred for definitive care of appendicitis are not found to have more advanced disease or have increased complications; however, they are exposed to significantly more ionizing radiation during evaluation for appendicitis.

A model predicting perforation and complications in paediatric appendicectomy

PURPOSE

To analyse the diagnostic value of simple clinical measurements in ensuring an early and accurate detection of advanced appendicitis (perforation, mass and peri-appendicular abscess) and possible complications.

METHODS

A retrospective, single-centre study of all paediatric (age 0-14 years) appendicectomies was conducted over a 14-year period. Preoperative symptoms, signs and laboratory results, intra-operative findings and postoperative complications were analyzed. Receiver operating characteristic (ROC) curves were used to estimate sensitivity and specificity of significant (p ≤ 0.05) predictor variables based on multivariate logistic regression models.

RESULTS

One thousand and thirty-seven patients were included. Perforations were seen in 88 (8.5%) cases, and abscesses were seen in 35 (3.4%) cases. Of all the clinical variables evaluated, preoperative temperature ≥37.5 °C was most discriminatory for advanced appendicitis. Significant other discriminatory clinical variables were WBC count ≥15,100/μL, preoperative anorexia and rebound tenderness. Postoperative complications occurred in 74 (7.1%) patients and were associated with pre-operative temperature ≥37.5 °C and advanced appendicitis.

CONCLUSION

Independent clinical predictors of advanced appendicitis exist but lack individual accuracy. In this study, preoperative pyrexia is shown to be highly associated with both advanced appendicitis and development of postoperative complications. This independent factor may point to early need for antibiotic treatment, urgent imaging and subsequent intervention in patients with appendicitis.

Initial antibiotic treatment for acute simple appendicitis in children is safe: Short-term results from a multicenter, prospective cohort study

BACKGROUND

Initial antibiotic treatment for acute appendicitis has been shown to be safe in adults; so far, not much is known about the safety and efficacy of this treatment in children. The aims of this study were to investigate the feasibility of a randomized controlled trial (RCT) evaluating initial antibiotic treatment for acute appendectomy in children with acute simple appendicitis and to evaluate the safety of this approach.

METHODS

In a multicenter, prospective cohort study patients aged 7-17 years with a radiologically confirmed simple appendicitis were eligible. Intravenous antibiotics (amoxicillin/clavulanic acid 250/25 mg/kg 4 times daily; maximum 6,000/600 mg/d and gentamicin 7 mg/kg once daily) were administered for 48-72 hours. Clinical reevaluation every 6 hours, daily blood samples, and ultrasound follow-up after 48 hours was performed. In case of improvement after 48 hours, oral antibiotics were given for a total of 7 days. At any time, in case of clinical deterioration or non-improvement after 72 hours, an appendectomy could be performed. Follow-up continued until 8 weeks after discharge. Adverse events were defined as major complications of antibiotic treatment, such as allergic reactions, perforated appendicitis, and recurrent appendicitis.

RESULTS

Of 44 eligible patients, 25 participated (inclusion rate, 57%; 95% CI, 42%-70%). Delayed appendectomy was performed in 2, and the other 23 were without symptoms at the 8 weeks follow-up. Minor complications occurred in three patients. None of the patients suffered from an adverse event or a recurrent appendicitis.

CONCLUSION

Our study shows that an RCT comparing initial antibiotic treatment strategy with urgent appendectomy is feasible in children; the intervention seems to be safe.

Pediatric appendicitis in a developing country: what are the clinical predictors and outcome of perforation?

OBJECTIVES

This study explored the risk factors and outcomes associated with perforation in children who underwent emergency appendicectomies.

METHODS

A retrospective cross-sectional study was conducted on children <13 years old who underwent appendicectomies in a Malaysian hospital in 2007.

RESULTS

One hundred thirty-four children underwent appendicectomies of which 118 were confirmed histologically. Sixty-one (52%) were perforated. Children with perforation had significantly longer duration of symptoms (p < 0.001), higher white cell count and absolute neutrophil counts (p = 0.013), with longer intra-operative period (p < 0.001) and post-operative recovery period (p < 0.001). Of the 52 samples of pus collected intra-operatively, 37 (71.1%) yielded positive cultures that were predominantly Escherichia coli (n = 27). Both the patients who had Staphylococcus aureus cultured from pus collected intra-operatively had significant pyogenic complications (scrotal pyocele and intra-abdominal abscess).

CONCLUSION

Children whose appendicitis were perforated had longer duration of symptoms, higher white cell counts and absolute neutrophil counts. Those with S.aureus cultured from intra-operative pus appeared to suffer more complications.

Opioid analgesia for acute abdominal pain in children: A systematic review and meta-analysis

OBJECTIVES

There are long-held concerns that analgesia in patients with acute abdominal pain may obscure the physical examination and lead to missing a diagnosis of appendicitis. Despite evidence to the contrary, analgesia continues to be underutilized and suboptimally dosed in children with acute abdominal pain. The objective of this systematic review and meta-analysis was to determine if opioids provide analgesia without an increase in side effects and appendicitis-related complications.

METHODS

Trials were identified through electronic searches of MEDLINE (1946-2013), EMBASE (1980-2013), Cochrane Central Register of Controlled Trials (2013), CINAHL (1981-2013), and Google Scholar (2013). All randomized controlled trials (RCTs) of children aged 0-18 years with acute abdominal pain that compared any opioid analgesic to placebo were included. The methodologic qualities of studies and the overall quality of evidence were evaluated using the Cochrane Collaboration's Risk of Bias tool and the Grading of Recommendations Assessment, Development, and Evaluation system, respectively.

RESULTS

Six RCTs met inclusion criteria, and each compared a single-dose parenteral opioid to a placebo, providing data on 342 children aged 5 to 18 years. The pooled mean pre/post difference in self-reported pain scores was 19.61 mm (95% confidence interval [CI] = -1.16 to 40.37 mm) lower in those receiving opioid analgesia. There was no significant increase in the risk of perforation or abscess associated with opioids in cases of appendicitis (relative risk [RR] = 1.03, 95% CI = 0.55 to 1.93). The risk of side effects was significantly greater in patients who received opioids (RR = 6.06, 95% CI = 1.10 to 33.49). Subtherapeutic dosing of opioids was detected in all six trials.

CONCLUSIONS

The use of opioids in undifferentiated acute abdominal pain in children is associated with no difference in pain scores and an increased risk of mild side effects. However, there is no increased risk of perforation or abscess. The overall quality of evidence is low, suggesting the need for larger, high-quality trials that are powered to detect both serious complications of appendicitis and determine the most efficacious opioid dosing for children.

Clinical presentation of acute appendicitis in adults at the Chris Hani Baragwanath academic hospital

BACKGROUND

Acute appendicitis is the most common surgical abdominal emergency. Delayed treatment increases the incidence of complications. The aim of this study was to investigate the presentation, incidence, and predictors of complications, and histological findings in adult patients with clinical diagnosis of acute appendicitis.

METHODS

The study was a prospective observational study and included patients aged 12 years and older diagnosed with acute appendicitis. Data collected included demographic data, clinical presentation, duration of symptoms and reasons for presentation delay, diagnostic investigations, operative and histology findings, length of hospital stay, and mortality.

RESULTS

A total of 146 patients were admitted with a mean age of 26 years (SD = 12 years). The male to female ratio was 1.6:1. Predominant presenting symptoms were right iliac fossa pain (95%), nausea (80%), and vomiting (73%), with 63% of patients presenting 2 days after onset of symptoms. Fever was present in 15% and only 31% of patients gave a typical history of acute appendicitis of vague peri-umbilical pain. The negative predictive values of white cell count and C-reactive protein for acute appendicitis were 28% and 50%, respectively. Sensitivity of the ultrasound to detect acute appendicitis was 60% with a negative predictive value of 31%; 30% of patients had complicated appendicitis. Histology results showed a normal appendix in 11% of patients. The 30-day mortality rate was 1.4%.

CONCLUSIONS

Patients with acute appendicitis rarely present with a typical history of vague peri-umbilical pain. The negative predictive values of both white cell count and ultrasound proved that neither of these measurements was accurate in the diagnosis of acute appendicitis. Most of our patients with complicated disease present late, with the most common reasons for this delay being lack of access to a medical clinics and prior treatment by general practitioners. Complications were higher in males and in those aged 45 years and above.

Do clinical outcomes suffer during transition to an ultrasound-first paradigm for the evaluation of acute appendicitis in children?

OBJECTIVE

The objective of our study was to examine whether the rate of complicated appendicitis and the hospital length of stay (LOS) increased during the transition to an ultrasound-first paradigm for the imaging evaluation of acute appendicitis.

MATERIALS AND METHODS

All pediatric patients with surgically proven appendicitis from 2005 to 2011 were identified by searching the hospital billing database for the discharge diagnosis codes for simple appendicitis (ICD-9 [International Classification of Diseases, 9th revision] code 540.9) and complicated appendicitis (ICD-9 codes 540.0 and 540.1). Annual trends of the proportions of these patients who underwent ultrasound and CT were determined and plotted for the study period. Correlation of complicated appendicitis and median hospital LOS with calendar year was assessed using the Spearman (ρ) rank correlation test. RESULTS. Eight hundred four patients met the inclusion criteria. The percentage of patients who underwent CT only showed a moderate downward association with year (ρ = -0.32, p < 0.01), and the percentage of patients who underwent ultrasound first showed a moderate upward trend (ρ = 0.44, p < 0.01). The percentage of patients with ultrasound as the only study performed before appendectomy increased moderately over the 7-year study period (ρ = 0.33, p < 0.01). The percentage of patients with complicated appendicitis and the median hospital LOS did not increase significantly over the study duration (ρ = -0.01, p = 0.74 and ρ = -0.04, p = 0.25, respectively).

CONCLUSION

The transition to an ultrasound-first pathway for the imaging workup of acute appendicitis in children occurred without evidence of a corresponding increase in the proportion of patients with complicated appendicitis or in the median hospital LOS.

Use of white blood cell count and negative appendectomy rate

BACKGROUND

Despite increased utilization of laboratory, radiologic imaging, and scoring systems, negative appendectomy (NA) rates in children remain above 3% nationwide. We reviewed the clinical data of patients undergoing appendectomy to further reduce our NA rate.

METHODS

A retrospective review was conducted of all appendectomies performed for suspected appendicitis at a tertiary children's hospital during a 42-month period. Preoperative clinical, laboratory, and radiographic data were collected. Variables absent or normal in more than half of NAs were further analyzed. Receiver operating characteristic curves were constructed for continuous variables by using appropriate cutoff points to determine sensitivity and false-positive rates. The results were validated by analyzing the 12 months immediately after the establishment of these rules.

RESULTS

Of 847 appendectomies performed, 22 (2.6%) had a pathologically normal appendix. The only variables found to be normal in more than half of NAs were white blood cell (WBC) count (89%) and neutrophil count (79%). A receiver operating characteristic curve indicates that using WBC cutoffs of 9000 and 8000 per µL yielded sensitivities of 92% and 95%, respectively, and reduction in NA rates by 77% and 36%, respectively. Results observed in the subsequent 12 months confirmed these expected sensitivities and specificities.

CONCLUSIONS

Absence of an elevated WBC count is a risk factor for NA. Withholding appendectomy for WBC counts <9000 and 8000 per µL reduces the NA rate to 0.6% and 1.2%, respectively. Missed true appendicitis in patients with normal WBC counts can be mitigated by a trial of observation in those presenting with early symptom onset.

Evaluation of a novel pediatric appendicitis pathway using high- and low-risk scoring systems

OBJECTIVES

This study aimed to determine the test characteristics of a pathway for pediatric appendicitis and its effects on emergency department (ED) length of stay, imaging, and admissions.

METHODS

Children age 3 to 18 years with suspicion for appendicitis at 1 tertiary care ED were prospectively enrolled, using validated low- and high-risk scoring systems incorporating history, physical examination, and white blood cell count. Low-risk patients were discharged or observed in the ED. High-risk patients were admitted. Those meeting neither low-risk nor high-risk criteria were evaluated by surgery, with imaging at their discretion. Chart review or telephone follow-up was conducted 2 weeks after the visit. A retrospective study before and after was also performed. Charts of a random sample of patients evaluated for appendicitis in the 8 months before and after the pathway implementation were reviewed.

RESULTS

Appendicitis was diagnosed in 65 of 178 patients. Of those with appendicitis, 63 were not low-risk (sensitivity, 96.9%; specificity, 40.7%). The high-risk criteria had a sensitivity of 75.3% and specificity of 75.2%. We reviewed 292 visits before and 290 after the pathway implementation. Emergency department length of stay was similar (253 minutes before vs 257 minutes after, P = 0.77). Computed tomography was used in 12.7% of visits before and 6.9% of visits after (P = 0.02). Use of ultrasound was not significantly different (47.3% vs 53.7%). Admission rates were not significantly different (45.5% vs 42.7%).

CONCLUSIONS

The low-risk criteria had good sensitivity in ruling out appendicitis. The high-risk criteria could be used to guide referral or admission. Neither outperformed the a priori judgment of experienced providers.

Antibiotic administration can be an independent risk factor for therapeutic delay of pediatric acute appendicitis

OBJECTIVES

Little is known about the relationship between prior treatment with antibiotics and delay of diagnosis and treatment in pediatric acute appendicitis (AA). We have defined a situation requiring more than 48 hours from the onset of symptoms to surgery in pediatric AA as "therapeutic delay." The aim of this study was to investigate the risk factors contributing to therapeutic delay in pediatric AA.

METHODS

We conducted a retrospective chart review of AA children operated on between 2003 and 2008 at tertiary-care pediatric and perinatal hospitals. Univariate and multivariate logistic regressions were analyzed to determine independent risk factors of therapeutic delay in pediatric AA.

RESULTS

The duration between the onset of symptoms and surgery was more than 48 hours (therapeutic delay) in 50 patients (25%, group A) and 48 hours or less in 151 patients (75%, group B). The patients in group A had a significantly higher frequency of diarrhea (48% vs 12%; P < 0.0001). The percentages of children who had previously received antibiotics were more frequent in group A (46% vs 8%; P < 0.0001). The median C-reactive protein levels (72 vs 7 mg/L; P < 0.0001) and frequency of perforation (60% vs 13%; P < 0.0001) were statistically significantly higher in group A. A multivariate analysis demonstrated that the independent risk factors of therapeutic delay were history of receiving antibiotics (odds ratio [OR], 5.8; 95% confidence interval [CI], 2.3-15.5), diarrhea (OR, 5.2; 95% CI, 2.1-13.1), and elevated C-reactive protein levels (OR, 4.5; 95% CI, 1.9-10.8).

CONCLUSIONS

Prior treatment with antibiotics was an independent risk factor for therapeutic delay in pediatric AA.

The effect of abdominal pain duration on the accuracy of diagnostic imaging for pediatric appendicitis

STUDY OBJECTIVE

Advanced imaging with computed tomography (CT) or ultrasonography is frequently used to evaluate for appendicitis. The duration of the abdominal pain may be related to the stage of disease and therefore the interpretability of radiologic studies. Here, we investigate the influence of the duration of pain on the diagnostic accuracy of advanced imaging in children being evaluated for acute appendicitis.

METHODS

A secondary analysis of a prospective multicenter observational cohort of children aged 3 to 18 years with suspected appendicitis who underwent CT or ultrasonography was studied. Outcome was based on histopathology or telephone follow-up. Treating physicians recorded the duration of pain. Imaging was coded as positive, negative, or equivocal according to an attending radiologist's interpretation.

RESULTS

A total of 1,810 children were analyzed (49% boys, mean age 10.9 years [SD 3.8 years]); 1,216 (68%) were assessed by CT and 832 (46%) by ultrasonography (238 [13%] had both). The sensitivity of ultrasonography increased linearly with increasing pain duration (test for trend: odds ratio=1.39; 95% confidence interval 1.14 to 1.71). There was no association between the sensitivity of CT or specificity of either modality with pain duration. The proportion of equivocal CT readings significantly decreased with increasing pain duration (test for trend: odds ratio=0.76; 95% confidence interval 0.65 to 0.90).

CONCLUSION

The sensitivity of ultrasonography for appendicitis improves with a longer duration of abdominal pain, whereas CT demonstrated high sensitivity regardless of pain duration. Additionally, CT results (but not ultrasonographic results) were less likely to be equivocal with longer duration of abdominal pain.