The Established Acute Surgical Unit: A reduction in nighttime appendicectomy without increased morbidity

Varying negative appendectomy rates after laparoscopic appendectomy: a systematic review and meta-analysis

PURPOSE

Appendicitis is a common cause of acute abdominal pain, and treatment with laparoscopy has become increasingly common during the past two decades. Guidelines recommend that normal appendices are removed if operated for suspected acute appendicitis. It is unclear how many patients are affected by this recommendation. The aim of this study was to estimate the rate of negative appendectomies in patients undergoing laparoscopic surgery for suspected acute appendicitis.

METHODS

This study was reported following the PRISMA 2020 statement. A systematic search was conducted in PubMed and Embase for retrospective or prospective cohort studies (with n ≥ 100) including patients with suspected acute appendicitis. The primary outcome was the histopathologically confirmed negative appendectomy rate after a laparoscopic approach with a 95% confidence interval (CI). We performed subgroup analyses on geographical region, age, sex, and use of preoperative imaging or scoring systems. The risk of bias was assessed using the Newcastle-Ottawa Scale. Certainty of the evidence was assessed using GRADE.

RESULTS

In total, 74 studies were identified, summing up to 76,688 patients. The negative appendectomy rate varied from 0% to 46% in the included studies (interquartile range 4-20%). The meta-analysis estimated the negative appendectomy rate to be 13% (95% CI 12-14%) with large variations between the individual studies. Sensitivity analyses did not change the estimate. The certainty of evidence by GRADE was moderate due to inconsistency in point estimates.

CONCLUSION

The overall estimated negative appendectomy rate after laparoscopic surgery was 13% with moderate certainty of evidence. The negative appendectomy rate varied greatly between studies.

Time to acute general surgical review: a retrospective study in a tertiary referral centre

BACKGROUND

The Acute Surgical Unit (ASU) is a busy service receiving Emergency Department (ED) referrals for adult and paediatric general surgery care alongside trauma. The ASU model deviates from the traditional on-call model and has been shown to improve efficiency and patient outcomes. The primary aim was to evaluate time to surgical review ED presentation and general surgical referral. Secondary aims were to assess referral numbers, pathology and demographics at our institution.

METHODS

A retrospective observational analysis was conducted on all referral times from the ED to the ASU between 1 April and 30 September 2022. Patient demographics, triage and referral times, and diagnoses were collected from the electronic medical record. Time between referral, review and surgical admission were calculated.

RESULTS

A total of 2044 referrals were collected during the study period, and 1951 (95.45%) were included for analysis. Average time from ED presentation to surgical referral was 4 hours and 54 min with average time to surgical review from referral taking 40 min. On average, total time from ED presentation to surgical admission was 5 h and 34 min. Trauma Responds took 6 min to review. Colorectal pathology was the most commonly referred disease type.

CONCLUSION

The ASU model is efficient and effective within our health service. Overall delays in surgical care may be external to the general surgery unit, or before the patient is made known to the surgical team. Analysis of time to surgical review is a key statistic in the delivery of acute surgical care.

Improving Venous Thromboembolism Prophylaxis Administration in an Acute Surgical Unit

OBJECTIVES

Venous thromboembolism (VTE) prophylaxis regimes frequently have a wide variation in application. Nepean acute surgical unit was established in 2006 as a novel model for emergency surgical care. As part of the model's rollout, there were several areas of clinical management targeted for improvement, one being VTE prophylaxis compliance. It was decided all patients older than 18 years treated for a variety of acute surgical conditions within the acute surgical unit should be administered routine VTE prophylaxis with heparin and compression stockings. A novel multifaceted intervention was implemented at the time to achieve this goal. The primary aim of this study was to determine VTE prophylaxis administration rates before and after this intervention.

METHODS

A before-after study conducted as a retrospective review of medical records of all patients 18 years or older, having an appendicectomy in 3 periods: Before acute surgical unit (ASU) (November 2004 to October 2006), Early ASU (November 2006 to October 2008), and Established ASU (January 2012 to December 2013). Outcomes were mechanical and pharmacological VTE prophylaxis administration rates for each group.

RESULTS

There were 1149 patients included in the study: Before ASU, 167; Early ASU, 375; and Established ASU, 607. There was a significant stepwise increase in parmacological VTE prophylaxis administration: Before ASU, 54.5%; Early ASU, 74.7%; and Established ASU, 96.9% (Before versus Early: odds ratio [OR], 2.46; 95% confidence interval [CI], 1.68-3.61; P < 0.001; Early versus Established: OR, 10.500; 95% CI, 6.29-17.53; P < 0.001). Mechanical VTE prophylaxis was significantly increased in the established group (Before versus Established: OR, 47.18; 95% CI, 25.61-86.91; P < 0.001).

CONCLUSIONS

There was a significant increase in VTE prophylaxis administration after the implementation of our multifaceted intervention. Allocating a responsible provider dedicated to VTE prophylaxis prescription and compliance checking was a key component to this intervention.

The acute surgical unit: An updated systematic review and meta-analysis

OBJECTIVE

To systematically review comparative studies on the acute surgical unit (ASU) model.

METHODS

Searches were performed of Cochrane, Embase, Medline and grey literature. Eligible articles were comparative studies of the Acute Surgical Unit (ASU) model published 01/01/2000-12/03/2020. Amongst patients with any diagnosis, primary outcomes were length of stay, after-hours operating, complications and cost. Secondary outcomes were time to surgical review, time to theatre, mortality and re-admission for patients with any diagnosis, and cholecystectomy during index admission for patients with biliary disease. Additional analyses were planned for specific cohorts, such as patients with appendicitis or cholecystitis.

RESULTS

Searches returned 9,677 results from which 77 eligible publications were identified, representing 150,981 unique patients. Cohorts were adequately homogenous for meta-analysis of all outcomes except cost. For patients with any diagnosis, compared with the Traditional model, the introduction of an ASU model was associated with reduced length of stay (mean difference [MD] 0.68 days; 95% confidence interval [CI] 0.38-0.98), after-hours operating rates (odds ratio [OR] 0.56; 95% CI 0.46-0.69) and complications (OR 0.48, 95% CI 0.33-0.70). Regarding cost, two studies reported savings following ASU introduction, while one found no difference. Amongst secondary outcomes, for patients with any diagnosis, ASU commencement was associated with reduced time to surgical review, time to theatre and mortality. Re-admissions were unchanged. For patients with biliary disease, ASU establishment was associated with superior rates of index cholecystectomy.

CONCLUSION

Compared to the Traditional structure, the ASU model is superior for most metrics. ASU introduction should be promoted in policy for widespread benefit.

Acute Care Surgery Models Worldwide: A Systematic Review

Background

The Acute Care Surgery (ACS) model was developed as a dedicated service for the provision of 24/7 nontrauma emergency surgical care. This systematic review investigated which components are essential in an ACS model and the state of implementation of ACS models worldwide.

Methods

A literature search was conducted using PubMed, MEDLINE, EMBASE, Cochrane library, and Web of Science databases. All relevant data of ACS models were extracted from included articles.

Results

The search identified 62 articles describing ACS models in 13 countries. The majority consist of a dedicated nontrauma emergency surgical service, with daytime on-site attending coverage (cleared from elective duties), and 24/7 in-house resident coverage. Emergency department coverage and operating room access varied widely. Critical care is fully embedded in the original US model as part of the acute care chain (ACC), but is still a separate unit in most other countries. While in most European countries, ACS is not a recognized specialty yet, there is a tendency toward more structured acute care.

Conclusions

Large national and international heterogeneity exists in the structure and components of the ACS model. Critical care is still a separate component in most systems, although it is an essential part of the ACC to provide the best pre-, intra- and postoperative care of the physiologically deranged patient. Universal acceptance of one global ACS model seems challenging; however, a global consensus on essential components would benefit any healthcare system.

Comparative analysis of emergency general surgery on-call structure and its impact on emergency appendicectomy outcomes

BACKGROUND

In Australia, there has been a shift from the traditional 'on-call' surgical model to the 'acute surgical unit' (ASU) model to improve outcomes in acute general surgery. Using emergency appendicectomy as a standardized procedure, we aimed to identify the different patterns of care between these on-call structures by comparing two metropolitan district hospitals; one that employs a traditional on-call model and the other, which employ the ASU model.

METHODS

Data on consecutive patients undergoing emergency appendectomies at the two hospitals (traditional and ASU model) between July 2018 and December 2018 were retrieved for retrospective review. Patient factors, preoperative factors, operative factors and post-operative outcomes were collected and tabulated for comparative analysis between the traditional versus ASU model of care.

RESULTS

Univariate analysis demonstrated that there were a greater proportion of consultant-led cases (P < 0.001), a shorter time to theatre (P = 0.047) and a greater number of out-of-hours operations (P < 0.001) in the ASU model compared to the traditional model. A larger proportion of patients from the traditional model underwent a computed tomography scan as part of their diagnostic workup compared to the ASU model (P < 0.001). There was no difference in negative appendicectomy rates, intraoperative conversion rates, post-operative complication rates or mean lengths of hospital stay between the two on-call models.

CONCLUSION

The ASU and traditional on-call model appears to achieve equivalent care outcomes for patients with acute appendicitis.

Outcomes of an acute care surgery model: a 10-year follow-up study

BACKGROUND

Many hospitals across Australia and New Zealand have implemented acute care surgery (ACS) models over the past decade, often with improved outcomes such as reductions in wait time to surgery, complications and length of stay. The aim of this study was to evaluate the outcomes of patients who underwent non-elective appendicectomy and cholecystectomy and compare these with the results observed shortly after the implementation of an ACS model at our institution 10 years earlier.

METHODS

A retrospective review of contemporary patients who underwent non-elective appendicectomy and cholecystectomy compared with historical data was performed. Primary outcomes were wait time to surgery, surgical complications and length of stay.

RESULTS

In the contemporary cohort, 263 patients underwent non-elective appendicectomy over a 1-year period compared with 226 patients in the historical cohort. The median wait time to surgery had increased (17.7 versus 9.6 h, P < 0.001). There was no significant difference in a composite end-point of complications and readmissions (8.0% versus 9.3%, P = 0.61). The length of stay was unchanged. There was greater use of preoperative imaging and reduced overnight operating. For non-elective cholecystectomies, 132 patients underwent this procedure in the contemporary cohort over a 2-year period compared with 115 patients in the historical cohort. There were no significant differences in wait time to surgery (2 versus 1 day, P = 0.13) or complications (9.8% versus 8.7%, P = 0.75). The length of stay was unchanged.

CONCLUSION

The majority of improvements seen shortly following the implementation of an ACS model have been sustained after 10 years.

Early Laparoscopic Washout may Resolve Persistent Intra-abdominal Infection Post-appendicectomy

BACKGROUND

Intra-abdominal abscess (IAA) complicates 2-3% of patients having an appendicectomy. The usual management is prolonged antibiotics and drainage of the IAA. From 2006, our unit chose to use early re-laparoscopy and washout in patients with persistent sepsis following appendicectomy. The aims of this study were to assess the outcomes of early laparoscopic washout in patients with features of persistent intra-abdominal sepsis and compare those with percutaneous drainage and open drainage of post-appendicectomy IAA.

METHODS

A retrospective case note review was performed for all patients having a laparoscopic washout, percutaneous drainage or open drainage following appendicectomy between January 2006 and December 2017.

RESULTS

During the period, 4901 appendicectomies occurred. Forty-one (0.8%) patients had a laparoscopic washout, 16 (0.3%) had percutaneous drainage, and 6 (0.1%) had an open drainage. The demographics, ASA grade and pathology at initial appendicectomy were similar. The mean time after appendicectomy was significantly shorter for laparoscopic washout (4.1 days vs. 10.1 and 9.0 days, p = <0.003). The mean time for resolution of SIRS was significantly shorter (2.0 days vs. 3.3 and 5.2 days, p <0.02). The morbidity and length of stay were similar.

CONCLUSION

Early laparoscopic washout for persistent intra-abdominal sepsis may be an alternative to non-operative management and delayed intervention for IAA and may have better outcomes than either percutaneous drainage or open drainage. A prospective randomised comparison is required to further evaluate the indications and role of early laparoscopic washout post-appendicectomy.

Laparoscopic appendicectomy is superior to open surgery for complicated appendicitis

BACKGROUND

Over the last three decades, laparoscopic appendicectomy (LA) has become the routine treatment for uncomplicated acute appendicitis. The role of laparoscopic surgery for complicated appendicitis (gangrenous and/or perforated) remains controversial due to concerns of an increased incidence of post-operative intra-abdominal abscesses (IAA) in LA compared to open appendicectomy (OA). The aim of this study was to compare the outcomes of LA versus OA for complicated appendicitis.

METHODS

A systematic literature search following PRISMA guidelines was conducted using MEDLINE, EMBASE, PubMed and Cochrane Database for randomised controlled trials (RCT) and case-control studies (CCS) that compared LA with OA for complicated appendicitis.

RESULTS

Data from three RCT and 30 CCS on 6428 patients (OA 3,254, LA 3,174) were analysed. There was no significant difference in the rate of IAA (LA = 6.1% vs. OA = 4.6%; OR = 1.02, 95% CI = 0.71-1.47, p = 0.91). LA for complicated appendicitis has decreased overall post-operative morbidity (LA = 15.5% vs. OA = 22.7%; OR = 0.43, 95% CI: 0.31-0.59, p < 0.0001), wound infection, (LA = 4.7% vs. OA = 12.8%; OR = 0.26, 95% CI: 0.19-0.36, p < 0.001), respiratory complications (LA = 1.8% vs. OA = 6.4%; OR = 0.25, 95% CI: 0.13-0.49, p < 0.001), post-operative ileus/small bowel obstruction (LA = 3.1% vs. OA = 3.6%; OR = 0.65, 95% CI: 0.42-1.0, p = 0.048) and mortality rate (LA = 0% vs. OA = 0.4%; OR = 0.15, 95% CI: 0.04-0.61, p = 0.008). LA has a significantly shorter hospital stay (6.4 days vs. 8.9 days, p = 0.02) and earlier resumption of solid food (2.7 days vs. 3.7 days, p = 0.03).

CONCLUSION

These results clearly demonstrate that LA for complicated appendicitis has the same incidence of IAA but a significantly reduced morbidity, mortality and length of hospital stay compared with OA. The finding of complicated appendicitis at laparoscopy is not an indication for conversion to open surgery. LA should be the preferred treatment for patients with complicated appendicitis.