Optimising outcomes for the high-risk surgical patient: models for postoperative care

Case history

A 78-year-old man presented to the emergency department with a 2-day history of nausea, vomiting and abdominal pain. His past medical history included type 2 diabetes mellitus and a myocardial infarction 10 years ago. Imaging confirmed the presence of small bowel ischaemia and he was scheduled for emergency surgery. A perioperative risk prediction tool was used and he was deemed to be at high risk of morbidity and mortality.

A critical care bed was unavailable due to capacity and staffing constraints. Nevertheless, the patient proceeded to have a general anaesthetic and an emergency laparotomy, and a small bowel resection was performed. As the patient had an uncomplicated intraoperative course, the consultant surgeon and consultant anaesthetist made the decision in the recovery room to send the patient to a bed in the surgical ward. Three days later, the anaesthetic resident conducted a postoperative follow-up and discovered that the critical care outreach team had attended the patient. This was because the patient had reduced urine output, low blood pressure and a high temperature in the preceding 24 hours.

Question to be answered

With more surgical procedures being performed on an increasing number of high-risk and multimorbid patients, what interventions can we deploy to identify complications and improve postoperative care?

This case study explores some of the practices utilised to optimise care during the postoperative period, including proleptic critical care admission, early assessment of the deteriorating patient by critical outreach teams and provision of dedicated higher acuity wards. Particularly, it explores and accumulates evidence for a routine, proactive, structured postoperative review by a dedicated perioperative physician.

Introduction

Globally, approximately 300 million surgical procedures are performed annually [1]. Mortality within 30 postoperative days is the third leading cause of death, accounting for 7.7% of all deaths [2]. This rate starkly underscores the need to reassess care during the perioperative period.

With reference to the case study, the risk of adverse outcomes following an emergency laparotomy is particularly high, especially for the elderly. An analysis of the National Emergency Laparotomy Audit (NELA) database demonstrated a 30-day mortality rate of 17.4% in people following an emergency laparotomy [3].

The occurrence of a postoperative complication is associated with decreased long-term survival [4, 5]. Hence, early detection of clinical deterioration can prevent complications and improve overall outcome [6]. The following sections provide an in-depth discussion about the effect of postoperative complications on the patient and review some of the preventative approaches.

Postoperative complications and their effect on the patient

The development of a postoperative complication within the first 30 days after surgery has a significant effect on patients’ outcomes. This effect is independent of the preoperative and intraoperative factors [5].

Cohort studies suggest that, whilst the rate of postoperative complications for specific surgeries is relatively consistent between institutions, the effect of those complications on patient survival rates varies between hospitals. Nearly a three-fold difference in mortality rates has been observed between the best-performing and worst-performing hospitals following one of eight major complications [6]. This phenomenon, known as failure to rescue (in other words, preventable patient deaths following a complication) has been used to evaluate the performance of a healthcare system [7]. Originally described in the early 1990s [8] and further exemplified in a seminal prospective multicentre study [9], failure to rescue is thought to be more representative of systemic variation in care processes than patient-specific factors. The global surgical health registry recently reported a surge in postoperative mortality rates after cancer surgery in lower-middle-income countries [9]. An important theme identified in that study was that advanced cancer treatment alone did not explain the variation in early death and postoperative complications. In that study, failure to rescue has been partly explained by the inconsistent provision of postoperative care processes, suggesting that the healthcare system greatly contributed to the increase in mortality rates. Organisational and systems factors implicated include bed capacity in the critical care unit, outreach services and a routine, proactive review of high-risk surgical cases.

In the context of our clinical case history, it is worth reflecting on actions that might have prevented the development of complications. For example, was this high-risk patient routinely reviewed by a dedicated perioperative team through a structured organ system review? When excluding bed capacity from the equation, would an admission to the critical care unit have made a difference? If so, what specific intervention would have been the most effective?

It is difficult to answer such questions. The following sections present evidence underpinning practices such as routine postoperative admissions in the critical care unit and provision of enhanced care wards, as well as acknowledging the potential role of proactive perioperative medicine reviews to offset complications.

Should all patients be admitted to the critical care unit following certain types of surgery?

Postoperative critical care is one potential pathway to reduce adverse outcomes. In the United Kingdom, the Royal College of Surgeons [10] and NELA [11] have formalised national recommendations for postoperative critical care admission when the calculated preoperative risk of death >5% within 30 days. However, clear variation was observed in the availability of beds in the critical care unit internationally [12]; in practice, almost one-third of the perceived high-risk patients are, in fact, admitted to a surgical ward postoperatively [13]. Almost one-quarter of ‘high-risk’ patients undergoing an emergency laparotomy are initially admitted to a surgical ward postoperatively, but subsequently require critical care admission, resulting in doubling the length of stay of a planned admission [14].

Our understanding of the benefit of perioperative critical care is evolving. The unmet need for a postoperative critical care bed may result in an increased risk of surgery cancellation [15] and evidence suggests that routine admission to the critical care unit after surgery is not uniformly beneficial [16, 17, 18, 19]. However, unplanned admission to the intensive care unit has been clearly linked to a higher rate of overall mortality [17].

More information is needed to reliably identify people who are most in need of this resource, acknowledging that not everyone will benefit equally. A recent systematic review identified several independent factors associated with an increased risk of requiring an unplanned critical care admission after surgery [20]. The patient in this case study had several of the nominated risk factors (e.g. advanced age, and emergent and major complex surgery).

In the context of resource limitations and uncertainty as to who most benefits from critical care postoperatively, more attention is being paid to how the high-risk surgical patient can be safely cared for outside the intensive care unit.

Could the provision of enhanced care help in preventing complications outside the Intensive Care Unit?

One potential alternative to optimise perioperative outcomes for the high-risk patient is the enhanced care model. This involves allocating a physical location in the hospital for similar patients requiring more advanced postoperative monitoring or treatment than the traditional ward-based care affords. This model may provide an improved staffing ratio when compared with that in normal ward care (e.g. 1:2 nurse-to-patient ratio); in some circumstances, this model deploys advanced cardiorespiratory monitoring and interventions (e.g. low-dose vasoactive therapy, goal-directed fluid therapy and invasive blood pressure measurement). A multicentre survey indicated that this model is already implemented and practised in approximately one-third of hospitals in the UK, Australia and New Zealand [12]. These high-acuity enhanced care beds are largely under the governance of the primary surgical team, and a minority of them have an intensivist or perioperative physician as the responsible clinician.

The Faculty of Intensive Care Medicine, in conjunction with the Centre for Perioperative Care, issued guidelines for developing such resources in the UK [21], which were invaluable in restarting routine surgical care pathways in the aftermath of the COVID-19 pandemic. Importantly, these areas should be considered as separate to, rather than a substitute for, critical care beds: the suggested admission criteria include patients with a calculated perioperative mortality risk of >1% (but <5%: these patients should still be considered for direct admission to the critical care unit), defined length of stay (e.g. 12–24 hours) or specific care (e.g. management of epidural) or monitoring needs (e.g. patients with a free flap).

The patient in our case study, who was recovering from an emergency small bowel resection, would probably have benefited from a period of enhanced observation and invasive haemodynamic monitoring considering his predicted perioperative risk.

Critical care outreach

Another approach to accessing critical care input at the ward level is the utilisation of the critical care outreach team. Rather than designating high-risk patients to a specific location, the focus is on reviewing patients identified as being at risk of deterioration. This is tracked by deviation from standard vital signs translated to early warning scores by the ward nurses, and this is a well-recognised method for early identification of deterioration [22]. The objective of this approach was outlined by the Department of Health in the UK a quarter of a century ago to implement a ‘whole systems approach that encompasses the needs of those at risk of critical illness and of those who have recovered from such illnesses, as well as the needs of patients during the critical illness itself’ [23].

Unfortunately, despite the long history, there is still a paucity of outcome data to support the outreach service in terms of reducing in-hospital mortality, length of hospital stay, cardiac arrest, admissions to the critical care unit and overall cost–effectiveness of the treatment [24, 25]. Despite the difficulty in consistently demonstrating an outcome benefit, many local and international critical care services rely heavily on an outreach service for the detection of patient deterioration, and this practice continues to be endorsed by the National Institute for Health and Care Excellence [26]. The value of this service may lie in the additional support provided by the critical care-trained team members to ward staff and patients [27]. The support measures include, but are not limited to, moral, educational, technical and application aspects of advanced medical therapies.

Perioperative medicine: a continuum of care

Perioperative medicine is an evolving specialty encompassing the integrated care of patients from contemplation of surgery to completion of care. The increase in the volume of surgical procedures among patients with more complex, multimorbid conditions continues to test healthcare systems and processes worldwide. Internationally, perioperative medicine pathways can bridge the gaps in care, reduce the occurrence of postoperative complications and improve patient outcomes [28].

In one model, postoperative care of the high-risk patient involves developing a proactive perioperative review service. This liaison role fills an important gap, as it is not activated by deterioration but rather constitutes a cross-speciality collaboration whereby patients identified as being high risk are routinely and proactively assessed to promote enhanced recovery and prevent complications.

The inclusion criteria in such reviews may comprise patient factors (e.g. age, frailty, objective risk scoring results and number and severity of comorbidities), surgical factors (e.g. type of operation, complexity and duration of surgery and intraoperative adverse events) and local hospital structures and processes (e.g. staffing considerations, physical location of the ward and availability of the critical care outreach team). This model of care has been trialled in several clinical settings internationally, most recently in the UK [29] and the Netherlands [30]. With regard to the emergency laparotomy cohort, a routine postoperative review by a physician for elderly care has been associated with a substantially lower mortality rate in those aged above 70 years [3]. One institution has described a significant (50%) reduction in the length of hospital stay following an emergency laparotomy after the introduction of an anaesthetic-led, multidisciplinary routine ward round [31]. Whatever medical speciality leads this service, the evidence base to support a co-ordinated proactive review of high-risk patients is evolving fast. Once established, there is potential for further enhancement to this service, such as the incorporation of remote automated monitoring. There is also an opportunity to design new pathways of care for day surgery, such as the use of smart wearable technology [32].

Conclusion

Designing new pathways that respond to the growing volume of increasingly comorbid patients is a key goal for developing perioperative medicine services. Investment in critical care beds and the development and expansion of enhanced care ward facilities are certainly two important pillars of this approach. However, we argue that a proactive structured postoperative review, integrated into standard ward care, designed to anticipate and address evolving complications, and focused on the quality of recovery, is of equal importance. Rather than comprising a single clinical role or location, this service reflects a process and an approach to the surgical patient. Anaesthetists are increasingly expanding their scope of practice, with a greater presence in patient management outside the walls of the theatre. A natural and complementary corollary of this is the delivery of comprehensive, patient-centred care that extends beyond the operating theatre, in other words, the practice of perioperative medicine.

Disclaimer

This Narrative article is adapted with permission from Case Studies in Perioperative Medicine, a UCL Press open access educational resource, available from https://doi.org/10.14324/111.444.9781787356917.14

Declarations and conflicts of interest