The results of this study suggest that in patients at high risk of post-operative mortality, laparoscopic emergency bowel surgery leads to a reduced length of critical care stay, overall length of stay and inpatient mortality compared to traditional laparotomy. By excluding low-risk patients with an estimated mortality risk of < 5%, and by utilising a propensity score weighted approach, we have attempted to address the risk of occult selection bias, as well as differences in patient demographics and pathology, to create a balanced group of patients for analysis.
This paper specifically focusses on high-risk general surgical patients as they are a resource intensive group with poor outcomes. High risk patients experience excess complication rates, they are frequently elderly and comorbid, they have complex needs and frequently require a prolonged length of hospital stay[6]. By including only high-risk patients undergoing surgery, this study focuses not only on the patient cohort most likely to require resource-intensive care, it also addresses clinically relevant differences in outcome such as ICU length of stay, for patients where UK national health policy now mandates post-operative care on a level 2 or 3 care unit.
The benefits of laparoscopy in gastrointestinal surgery are well established. Laparoscopy permits surgery through smaller incisions, there is reduced blood loss and there is a reduced systemic inflammatory response to surgery[15–17]. Post-operatively, data have suggested that this translates into an earlier return of respiratory and gut function and reduced analgesic requirement[16, 18]. Laparoscopy reduces length of stay and there is reduced morbidity and mortality[19]. These reductions in mortality have been shown to reduce hospital costs [20]. Longer term benefits of laparoscopy are furthermore to be expected with reduced rates of incisional hernia and adhesional intestinal obstruction [21].
The most recent NELA report observes that 19% of emergency cases were attempted with laparoscopy - this figure has remained static since 2018[7]. It is unclear why this is the case as there is sufficient surgical ability to support the use laparoscopy in the emergency setting. Laparoscopy is commonplace in major elective surgery; the laparoscopic approach is the gold standard for the majority of upper gastrointestinal procedures, in colorectal surgery, data from the National Bowel Cancer Audit shows that laparoscopic resection rates have increased annually since 2013 (48 to 61%). Similarly, appendicitis and acute biliary conditions are now managed overwhelmingly with laparoscopy[22, 23]. Data from randomised controlled trials, meta analyses and international guidelines increasingly support the use of laparoscopy to manage perforated peptic ulcer, small bowel obstruction and diverticulitis [24–26][27] [28] [29] [30]. Despite this, two recent surveys have shown that the choice of surgical approach is heavily influenced by subspecialty, time since completion of training and personal preference [31, 32].
It is crucial to challenge the dogma that laparoscopy in the emergency setting is challenging owing to limited space to operate and fears of causing enterotomy. Evidence from the LASSO trial shows that iatrogenic bowel injury was similar in patients undergoing open and laparoscopic groups [25]. Conversion rates of 19–25% have been reported in the laparoscopic management of diverticulitis and small bowel obstruction showing that laparoscopy is feasible in the majority of patients [25, 33].
In this study, almost half of laparoscopic procedures in high-risk general surgery cases were converted to open. Despite this, a reduced ICU stay and overall length of stay was seen where procedures are started laparoscopically when compared to operations that are performed open. This was demonstrated in a previous paper whereby patients whose case was started laparoscopically still benefitted from reduced blood loss, a shorter duration of hospital stay and a reduced risk of death even if the procedure was converted to laparotomy [9]. Without knowing the reasons for conversion, this suggests that procedures were unlikely to have been converted to open due to any ill effect of laparoscopy. Furthermore, if a procedure was converted to a laparotomy because of a negative effect of laparoscopy (such as pneumoperitoneum or extreme positioning) the impact is transient. It is our own experience that an initial laparoscopy can localise and mobilise problematic bowel resulting in a smaller abdominal incision. If a case is not amenable to laparoscopy this is often immediately apparent and the case can be converted to laparotomy with little time wasted.
Mortality, morbidity and length of stay are frequently used as endpoints to demonstrate the superiority of laparoscopy over open surgery. This paper is unique in that it investigates the impact of laparoscopy on critical care stay. ICU stay is a useful marker for severity of illness, organ failure and response to surgery. Laparoscopy was seen to reduce the length of ICU stay independent of patient and disease characteristics. Reducing length of ICU stay has benefits for both patients and healthcare providers. There is evidence that patients with a prolonged length of critical care stay have worse short-term outcomes. These start to become apparent as soon as after 48 hours of critical care admission[34]. Similarly, a prolonged length of ICU stay is associated with worse long-term physical, psychological and cognitive outcomes[34]. Reducing the length of ICU stay has been shown to reduce the length of overall stay, analysis of a large North American database has shown that for every day spent in a critical care bed patients spend an extra 1.5 days in a regular ward bed[35]. For healthcare providers there is a potential financial advantage- ICU patients are resource intensive, a large proportion of hospital budgets are spent on a small number of patients. Critical care treatment is most expensive in the first five days of admission. The exact cost of critical care treatment per-day is difficult to calculate as this varies according to the complexity of the patient and condition being manged but data from Canada has shown that by reducing the length of critical care stay by one day can reduce hospital expenditure by 1% or equivalent to £500,000 in a year[36].
Patients undergoing laparoscopic surgery were less likely to be admitted to critical care than those patients who had open surgery (47.9% vs 61.7%, p < 0.001). The most recent NELA report shows that currently 82% of high-risk patients are now admitted to critical care following major emergency general surgery. This is likely due in part to the Emergency Laparotomy Best Practice Tariff introduced in April 2019. Given that patients undergoing laparoscopy are less likely to require ICU admission, it may be possible that some patients are now being unnecessarily admitted to ICU. This echoes previous work that has shown that risk prediction models over call risk in patients undergoing emergency laparoscopic surgery[37]. It is clear that in selected patients laparoscopy leads to improved outcomes and the choice of surgical approach should factor into any discussion about risk prediction and post-operative care.
It is important that surgeons use intensive care services appropriately and reduce the demand for beds where possible. ICU beds are currently under extreme demand. The UK has a reduced number beds per capita compared to North American and European nations [38]. Prior to the pandemic these beds were operating at 81% capacity[39]. The highest level recommended for safe and efficient patient care is 85%[40]. There is expected to be an annual increase in demand for critical care services of around 4% per year[41]. These beds are likely to be occupied by our aging and increasingly comorbid population [27]. When demand for ICU beds outstrips supply there is an impact on the provision of elective surgery and in extreme cases the quality of care[42]. A recent national audit demonstrated that a lack of critical beds was the leading cause for cancelled surgery [43]. Prior to the pandemic, it was estimated that nationally 280 urgent operations are cancelled each month due to a lack of ICU beds[39]. Cancellation of procedures causes emotional distress, has financial implications and has been demonstrated to leads to worse clinical outcomes amongst patients [44].
Any interrogation of the NELA database is inevitably limited by the quality and completeness of data inputted and omitted. This will inevitably introduce bias into the dataset which may not be addressed by our analytic approach with unpredictable consequences. However, our study used well validated methods, including multiple imputation and propensity score weighting, to address known sources of bias which facilitates robust analysis. A further limitation is that we have only observed the length of critical care admission and not the interventions provided by ICU such as the level of organ support. Given the unpredictable nature of emergency surgery it is challenging to conduct largescale RCTs. Analyses from large population-based data are fundamental to inform best practice.
The quality of care for emergency general surgery patients is dependent on support from theatres, radiology teams and critical care capacity. This must be supported by appropriate consultant, medical and nursing cover [45] [46]. These all require training, recruitment and infrastructure change. This costs money and change can be slow. Most gastrointestinal surgeons utilise laparoscopy in their elective work and most hospitals possess laparoscopic equipment. A conscious decision to increase the uptake of laparoscopy for emergency cases could yield immediate improvements to outcomes at both patient and system level, with little extra cost.