The expression ‘Peri-operative Medicine’ (POM) is used increasingly in the medical literature; however, there is no consensus regarding its definition. The aims of this narrative review are to conceptualise POM and support the practice of POM by anaesthesiologists. It summarises basic knowledge about the epidemiology, pathophysiology and risk factors associated with outcomes in surgical patients. Next, it describes interventions and components of peri-operative patient care that have been shown to change outcomes, with a focus on the reduction in the incidence and severity of major adverse events (MAEs) in high-risk patients. Based on this framework, the review discusses how individual components can be integrated into overarching conceptual models and proposes a pragmatic definition of POM. The review ends with a discussion on the implementation of POM.
Diseases treated with surgery
The burden of diseases treated by surgery continues to grow; in 2012 an estimated 312 million surgical procedures were conducted worldwide.1 Although definitions of surgery and the types of surgical procedures differ from country to country, studies suggest that this growth applies to all economic and social environments.2 Increased life expectancy is associated with higher rates of surgical interventions, with a ceiling effect reached at around 1533 operations per 100 000 people.1 Longevity is expected to increase in the near future3 and may be associated with increased frailty, comorbidities and need for surgical interventions. Therefore, more high-risk patients are expected to be exposed to surgery, anaesthesia and peri-operative care.
Outcomes after surgery
Mortality, disability and health-related quality-of-life are important patient-relevant outcomes.4,5 In Europe and high-income countries, most epidemiological data on mortality originate from national registries6,7 and large prospective studies.8–10 Crude short-term mortality rates vary widely and depend on a variety of factors such as patient's health status, type and urgency of surgery, healthcare provider density and skills, patient volume and time of follow-up. The EuSOS study documented an in-hospital mortality rate of 4% that varied widely across European countries.9 Other nation-wide or more recent studies document lower mortality rates6,8,10–12 yet the key messages from these investigations are similar: surgical populations are heterogeneous and discrete groups of high-risk patients with higher than average mortality. In one large cohort, up to 80% of peri-operative deaths occurred in 12% of patients at high-risk.11 The identification of these high-risk populations is challenging (Fig. 1). The complex interplay between patient, surgery, anaesthesia, process and infrastructural factors is commonly overlooked in peri-operative care studies.
Although data exist regarding the long-term outcomes of discrete surgical populations (e.g. colon cancer patients), few studies describe outcomes beyond 30 days after surgery and the factors influencing them. In a landmark study, Khuri et al.13 demonstrated a 30-day mortality rate of 3% after major surgery, and a 36% mortality rate after an average follow-up period of 8 years. In a comprehensive risk-adjusted analysis the authors demonstrated that postoperative MAEs had a major impact on short-term and long-term survival. The association between postoperative MAEs and mortality is particularly relevant in the elderly.14,15 These findings triggered a turning point in peri-operative management and put focus on the prevention or early treatment of postoperative MAEs with the aim of improving survival.16
Risk factors associated with outcome
The association between several peri-operative risk factors, postoperative MAEs and patient-relevant outcomes is now established and allows the stratification of patients according to risk class. Historically, a first important step was the recognition that nonclinical, patient-independent factors such as the academic level of hospitals, nurse education, nurse-staffing, and workload have a significant impact on patient's recovery and survival after surgery17–19 (Fig. 1). A second step was the identification of a number of potentially modifiable factors such as frailty (a state of decreased physiological reserve with increased vulnerability to stressors20) associated with patient-relevant outcomes such as mortality, disability and health-related quality of life. Third, interventions targeting organ protection21 and management measures22,23 were shown to improve outcomes. A last step was the recognition that patients identified as high-risk may benefit from dedicated peri-operative care pathways.24,25 However, pathways involving increased utilisation of intensive care do not seem to have a significant impact on mortality in specific populations such as elective surgery or elderly patients.26–28
Peri-operative pathophysiology and organ injury
Triggers and phases of peri-operative stress
Peri-operative stress plays a major role in organ injury and dysfunction, which is the pathophysiological basis of postoperative MAEs, acute illness and outcome (Fig. 2). In the absence of a consensus definition, we define peri-operative stress as the collective physiological response to stimuli occurring before, during and after surgery. This response is modulated, amongst other things, by the stimuli, how they are perceived (threatening or benign), the individual's genome, previous health status (including frailty and comorbidities) and the environment. Different threats (e.g. anxiety, fasting, dehydration, surgical trauma, inflammatory substances, infection) can trigger and modulate the stress response throughout the peri-operative period. The response to stress can be divided into 3 successive phases.29 The first two, coined Alarm and Resistance,29 are characterised by the nonspecific activation of the immediate reaction systems and evoke, in most cases, a useful, localised, adaptive response to threats, crucial to the healing process after injury. However, certain individuals in the face of severe, prolonged or repeated threats, as often occurs in the peri-operative period, can enter a 3rd stage (Exhaustion) in which the response itself becomes more damaging than the threat and results in organ injury.30
Immediate response to peri-operative stressors
An almost immediate reaction in response to threats is the activation of the autonomic nervous system and the hypothalamic–pituitary–adrenal axis preparing the body for the ‘fight-or-flight’ response. This reaction is mediated by endogenous catecholamines. Adrenocorticotropic hormone released by the anterior pituitary mediates the release of adrenal cortisol into circulation.31 In the short term, cortisol further stimulates the adrenal medulla to liberate adrenaline32 and stimulates gluconeogenesis and glycogen breakdown in the liver and skeletal muscle, contributing to peri-operative hyperglycemia.33 By-products of tissue damage and components of bacteria are sensed by pattern recognition receptors, notably Toll-like receptors, on the surface of cells of the innate immune system triggering local release of cytokines.34 Cytokines recruit neutrophils and activate coagulation and complement cascades contributing to limit the spread of damage.
Peri-operative stress and organ injury
During the peri-operative period prolonged and/or severe local pro-inflammatory mediators can spill over to the circulation triggering a systemic inflammatory syndrome (SIRS) and exaggerated sympathetic stimulation.30 Excessive inflammation has been directly associated with adverse effects at organ level, for example postoperative delirium,35 myocardial injury36 and acute kidney injury (AKI).37 Continuous exposure to catecholamines modulates metabolism resulting in insulin resistance and hyperglycaemia, which has been shown to directly cause cellular injury.38 Excessive catecholamines may also precipitate arrhythmia and result in increased cardiac workload that is associated with postoperative myocardial ischemia.39 Both prolonged SIRS and catecholamine exposure further modulate the immune response and stimulate bacterial growth resulting in a phenotype with increasing susceptibility to postoperative infection and sepsis.34 In the lungs, recruitment and activation of neutrophils and macrophages can result in breakdown of the alveolar-capillary membrane, capillary leakage and loss of surfactant, which contribute to postoperative pulmonary oedema and atelectasis.40 Finally, exaggerated amplification of the coagulation cascade can result in a hypercoagulable state increasing the risk of postoperative thromboembolic complications (e.g. pulmonary embolism) and organ-level injury (e.g. acute kidney or myocardial injury).40
Goals of peri-operative care
Peri-operative care and postoperative major adverse events
Historically, the first task of anaesthesia was to secure intra-operative care and avoid death during surgery. High intra-operative safety was achieved in the past decades.41 However, postoperative mortality is still not zero and is related to postoperative MAEs.10,42 There may be a causal link between postoperative MAEs and postoperative mortality in high-risk patients.13,43
Studies in the early 1990s reported an association between postoperative MAEs and unfavourable outcome. These observations led to the concept of ‘failure-to-rescue’,44 meaning that a failure to adequately identify and manage MAEs when they arise leads to death. Some frequent postoperative MAEs with high death rates are bleeding, unplanned intubation, sepsis, pneumonia, kidney failure, myocardial injury and infarction and stroke.16,43 A low failure-to-rescue rate is a key feature of high quality in peri-operative care.45
Components of peri-operative care
Key components of peri-operative care are as follows (Fig. 3):
- Early risk assessment with identification of high-risk patients and communication of this risk to patients, proxies, and between healthcare professionals; this may include offering alternative care strategies to the highest risk patients, based upon patient values and predefined goals of care.
- The application and coordination of peri-operative pathways tailored according to the risk of MAEs during critical time periods before (optimisation) and after interventions (avoidance of failure-to-rescue). Frequent risk assessment allowing patients to be transferred to a different pathway if risk prediction changes throughout the peri-operative period is essential because predictive models are imperfect.
- Patients with a low risk of MAEs should be identified allowing a cost-effective46,47 means to
- use enhanced recovery after surgery (ERAS) programmes in low or intermediate-risk patients and
- concentrate resources on high-risk patients.
- High-risk patients should benefit from
- optimisation of their physical and mental status to minimise risk of adverse events;
- peri-operative organ protection;
- improved peri-operative surveillance and complex care management with regular risk assessments for early recognition of adverse advents. This may include planned admission to high-intensity care units (intermediate or intensive care) and follow-up of high-risk patients on the ward by specialised teams.
All these components are core competencies of anaesthesiologists.
Peri-operative interventions to improve outcomes
MAEs can occur in the pre-, intra- and post-operative periods, but a significant proportion of MAEs leading to death occur in the first 24 to 48 h after surgery.48,49 Therefore, early postoperative care is an important, logical focus for peri-operative care, and so the assessment of the effect of peri-operative interventions has been focused on postoperative events. There is good evidence suggesting that high-risk patients develop postoperative MAEs even in high performance teams and hospitals.50 Postoperative MAEs are associated with increased health costs.51 A main interest of peri-operative care is to manage these MAEs efficiently, that is with early identification and continuous optimisation, even with limited healthcare resources. Several interventions in the peri-operative period have been shown to improve outcomes of high-risk patients. Table 1 summarises a number of pre-operative,52–66 intra-operative21,64,67–71 and postoperative64,72–80 interventions that can be implemented locally.
Overarching models of peri-operative care
Based on the framework of peri-operative care presented so far, the following definition of POM is proposed: POM is the patient-centered and value-based multidisciplinary peri-operative care of surgical patients, with a particular focus on high-risk patients. This definition does not use the word ‘recovery’ because ‘recovery’ is not easy to define and may be an unreasonable target, particularly in patients that are unlikely to benefit from surgery. In addition, the definition is inclusive to encompass the care of patients that, despite having a medical condition that could be treated with surgery, do not actually undergo a surgical procedure and are directed to alternative pathways such as palliative care (Fig. 3). A further advantage of this definition is that it proposes a value-based approach, that is with the inclusion of patient's values as well as cost-effectiveness.81 Furthermore, it focuses on the ‘natural’ competencies of anaesthesiologists to handle high-risk patients successfully.
The goals of POM are to promote high quality recovery, and to reduce disability, MAEs and mortality after surgery, with a rational use of available resources. Although the principles of POM should apply to all surgical patients, high-risk patients are most likely to benefit from POM and its key components.82 An important added value of POM is the optimum tailoring of complex care and resource management for high-need, high-cost patients. In agreement with these aims is the avoidance of indiscriminate peri-operative testing and interventions, which is a pillar of Choosing Wisely initiatives across the globe.83
The addition of POM to anaesthesia expands the role of the anaesthesiologist and represents a focused care strategy for high-risk patients, that is those who present increased risk of MAEs, prolonged length of hospital stay, and unfavourable outcomes. A large proportion of patients submitted to nonelective surgery are high-risk patients and are of particular interest for POM.
Although individual peri-operative interventions have been shown to improve postoperative outcome, more evidence is needed to demonstrate the benefit of POM as a complex model of care with multiple components. Some existing examples are the improved survival reported after implementation of an efficient pre-operative frailty screening instrument.25 Risk-adjusted peri-operative mortality rates decreased in high-risk operations between 8 and 36% over a 10-year period;84 this decrease of fatal outcomes may potentially be related to decreased rates of postoperative major adverse cardiac events85,86 and decreased mortality after postoperative sepsis.87,88 One important study underway in the United Kingdom, the Peri-operative Medicine Service for High-risk Patients Implementation Pilot (POMSHIP),89 will evaluate the clinical effectiveness and costs of a 3-component service that includes: first, individualised pre-operative risk assessment; second, postoperative admission to a critical care unit for high-risk patients and; third, postoperative follow-up in the ward by a dedicated team.
Enhanced recovery after surgery
Different peri-operative concepts have been developed to tackle high postoperative morbidity and prolonged duration of hospitalisation; the ‘enhanced recovery after surgery’ (ERAS) multicomponent programme is one of the earliest expressions of the principles of comprehensive peri-operative care. ERAS programmes are patient-centered, adhere to the culture of quality and safety, and depend on efficient inter-professional communication to improve coordination of care and to avoid overtreatment. ERAS uses evidence-based practices to decrease the potential need for postacute care services, readmissions, disability and mortality. The unifying goals of POM and ERAS concepts are avoidance of harm and reducing variation in practices, in an effort to ensure the best possible long-lasting recovery after surgery. However, ERAS programmes focus on homogenous subgroups of low-to-moderate risk patients defined by the type of surgery. ERAS propose standardised, routine, cost-effective peri-operative pathways including ambulatory care.90 POM is a broader approach offering risk-adapted, coordinated pathways, including high intensity individualised care of hospitalised high-risk patients, that may have poor outcome without further support.11 Leadership may also be different, whereas the concept of ERAS is often surgeon driven, the concept of POM is often anaesthesia and critical care driven. These concepts are therefore complementary, and ERAS can be seen as a care pathway adequate to low-intermediate risk patients within the scope of POM.
Risk assessment in peri-operative medicine
For tailored peri-operative management, that is to concentrate preventive and therapeutic efforts on patients most likely to benefit from them, and to avoid inefficient or even detrimental resource utilisation, the estimation of a patient's risk is crucial. Early identification of high-risk patients and optimal risk stratification are cornerstones of POM. Initial pre-operative risk stratification should be questioned during the whole peri-operative period as it may need revision throughout hospitalisation. Several approaches to peri-operative risk stratification have been proposed with risk scores,91–95 biomarkers, and additional testing, for example cardiopulmonary exercise testing (CPET).96,97
Peri-operative risk scores can be classified according to the predicted outcome and the timing of the risk estimation (Table 2). There are scores that predict all-cause mortality,52,91,92,95,98–102 cardiac complications,95,103–106 pulmonary complications,95,107 renal complications108 or postoperative complications and death.91,109–111 Discharge scores from monitored units such as the Aldrete score112 could be useful to predict survival in non-monitored units but their prediction performance remains unclear.113
Many scores are user-friendly because they are based on simple information collected from the patient's history or basic laboratory tests. Others are complex and are more useful within the context of risk prediction in scientific investigations. External validation is a limitation of many peri-operative scores.91 While most scores allow for risk stratification that can be used for communication and care planning, individual risk estimations are seldom possible. Further, only few risk scores include pre-operative chronic treatment, which could potentially improve the performance of prediction models. Finally, specific risk scores for common MAEs such as delirium, bleeding and sepsis are still lacking. Recent predictive models based on machine learning techniques applied to large datasets from electronic healthcare records and anaesthesia information management systems,114,115 do not appear to improve discrimination over more simple validated risk stratification tools.
Despite all limitations, clinical risk scores are the basis of early identification of high-risk patients and should support decision-making within specific clinical and coordinated pathways.
Biomarkers may improve the prediction performance of risk scores. Cardiac biomarkers are particularly well established and most biomarkers with reasonable predictive performance focus on predicting cardiac adverse events (Table 2). Nevertheless, biomarkers associated with other MAEs have been identified and may be used in clinical practice to help identify high-risk patients throughout the peri-operative period. Thus, biomarkers are not only of interest for pre-operative risk stratification but also for peri-operative surveillance with sequential risk re-assessments for early recognition of adverse advents.
Troponin (and since its introduction high-sensitivity troponin)116–120 and natriuretic peptides116,118,121 have been extensively studied, whereas other markers are still insufficiently explored.122–127
The discriminative ability of pre-operative high-sensitivity-troponin to predict postoperative mortality is moderate to good (Table 2).116,118 Increased pre-operative high-sensitivity-troponin values are significantly associated with major cardiovascular events and mortality after surgery;116–120,128 however, many studies report a high prevalence of high-sensitivity-troponin exceeding the 99th upper reference percentile pre-operatively.116–120 This high-prevalence results in poor positive predictive values and risk misclassification,116–120 if pre-operative troponin is not combined with other risk stratification tools.
In the context of risk-reassessment using sequential biomarkers measurements, elevated high-sensitivity-troponin after noncardiac surgery was significantly associated with noncardiac complications,129 30-day43 and 1-year mortality119 independent of the presence of symptoms and ECG changes.
The discriminative ability of pre-operative natriuretic peptides to predict 30-day mortality and myocardial infarction (MI) was reported as moderate in a large individual patient level data meta-analysis (Table 1).121 The addition of natriuretic peptides to clinical risk scores may improve prediction for postoperative outcomes.97,121
Urinary output and serum creatinine are key parameters for the diagnosis of AKI. However, interpretation of their changes in the peri-operative period is challenging. Cystatin C, a functional biomarker, revealed good discrimination for AKI in a variety of settings.130 Several renal damage biomarkers have been proposed in the setting of cardiac surgery131: neutrophil gelatinase associated lipocalin (NGAL), for example, demonstrated moderate-to-high discrimination for AKI, yet with a high level of heterogeneity.131,132 For noncardiac surgery a prospective cohort study suggested moderate discrimination for endostatin, NGAL and cystatin C for recovery from AKI.133 Biomarkers of renal damage remain underexplored in noncardiac surgery.
A host of other biomarkers such as pre-operative albumin134,135 and haemoglobin (Hb),136–138 hyperglycaemia94–96 and C-reactive protein97,139 are associated with increased postoperative mortality and morbidity. However, whether these biomarkers are independent risk factors or provide additional value to current risk scores remains under-investigated. Similarly, postoperative biomarkers such as Hb, glucose and lactate have been shown to be associated with MAEs such as bleeding, infection and other major MAEs92,98–101 but remain inadequately studied.
There are three ways of characterising functional capacity: subjective assessment of daily activities with estimation of metabolic equivalents (METs), structured questionnaires to estimative METs and CPET. Based on earlier small-scale studies, international guidelines recommended the use of METs, based on subjective reporting, as a means of identifying high-risk patients to trigger more intensive investigations before noncardiac surgery.140,141 The basic idea was that a surgical intervention is a stress and therefore, pre-operative exercise capacity estimation (a stress estimation) is associated with stress-related postoperative MAEs, in particular cardiac events. This view was recently challenged with the publication of the large international prospective METS study.97 In this METS study, subjective assessment of functional capacity with METS was not related to cardiopulmonary fitness on the CPET and was not useful to predict postoperative morbidity or mortality. Furthermore, neither peak oxygen consumption nor anaerobic threshold measured using CPET was associated with 30-day mortality or MI, and CPET did not improve prediction of these events over more simple clinical scores.97 However, CPET-derived peak oxygen consumption did improve prediction of a composite outcome of postoperative complications.97 Of note, the use of a structured questionnaire on exercise capacity, the Duke Activity Index Scale, led to a correct reclassification in 23% of the patients for the prediction of 30-day mortality or death.97 However, the optimum score necessary to appropriately discriminate between favourable and unfavourable outcomes is unknown.
Given the strong association between pre-operative frailty and postoperative outcomes142,143 it is rational that frailty-associated features could be useful risk-stratification tools. A potential postoperative risk factor could be the absence of early ambulation, which is related to prolonged hospital stay.144,145 Another potential risk factor could be the absence of early feeding, which is also related to prolonged hospital stay.146
Despite being considered as a major health hazard,147 postoperative hypoxaemia has not been investigated as a predictor of postoperative MAEs. Fluid balance68,148 at the end of intervention or peri-operative heart rate149 may be risk factors for postoperative MAEs. Early postoperative cognitive dysfunction may be a good predictor of long-term outcomes.150–152
Management in Peri-operative Medicine
The application of research results to clinical practice directly benefiting patients may take decades to occur.153 Nonclinical aspects may contribute to a faster implementation of POM.154 POM encompasses the optimised care of the high-risk surgical patient, from contemplation of surgery to postoperative care, which may include surveillance and care after hospital discharge. This demands a wide medical repertoire and the coordination of different medical and paramedical specialists. These principles should be adaptive allowing for peri-operative pathway changes according to individual needs. Therefore, management of peri-operative care is much more than operating room planning.
The application of the principles of POM is likely to be context-specific and influenced by local infrastructure, hospital and surgical volume (high volume is more favourable), a stable peri-operative team with physician coverage and an adequate nurse-patient-ratio (higher number of nurses is more favourable), the distribution of high-risk patients over time (avoidance of peaks of high-risk patients by optimising scheduling of elective procedures) and the preparedness for emergency cases (Fig. 1). Therefore, peri-operative management should integrate local specificities (e.g. legal or cultural) and restrictions (e.g. in terms of available resources) with standardised evidence-based recommendations from National155–158 and International52,140,159–174 guidelines (Table 3). Possible interventions for quality improvement initiatives along the whole peri-operative period have been described earlier (Table 1). Potentially, multiprofessional collaborative activities may be more effective for behavioural changes of healthcare providers.175,176
Basics of peri-operative management
Successful peri-operative management includes aspects of structure (organisation of peri-operative care), process (what, when and how it is being done) and outcomes (healthcare results).177
Structural aspects are represented by dedicated clinical pathways for high-risk patients with repeated risk assessment pre-operatively, at the end of surgery and the end of monitored postoperative care. Effective process management of high-risk patients may be performed with simple elements such as checklists, standardised procedures, ready-to-use sets and solutions, preprepared charts and defined pathways. The communication (feedback) and discussion of predefined outcomes are essential elements of permanent quality improvement and optimisation.
Critical features of peri-operative management
The focus of peri-operative management is the reduction in the incidence and severity of MAEs. Therefore, local implementation of POM should consider the development of structures and processes (Fig. 3) enabling:
- Accurate pre-operative identification of high-risk patients with precise risk stratification followed by allocation to specific pathways with tailored interventions, optimisation and organ protection.
- Frequent risk re-assessment during the entire peri-operative period, particularly during critical peri-operative checkpoints (i.e. before surgery, at the end of surgery and before discharge from monitored units to the ward), ensuring allocation to the most appropriate care pathways at each step.
- Early identification of adverse events and adequate communication of MAEs among healthcare providers for optimal treatment, and established communication channels with the patient and proxies.
- Clear task responsibilities among healthcare professionals during the whole peri-operative period.
- Appropriate administration of drugs, transfusions and fluids, with consideration of their potential for adverse events.
- A programme and measures for (hand) hygiene during the peri-operative period decreasing the rate of unplanned postoperative nosocomial infections.
These critical aspects with a high error potential, in particular in nonelective patients, may be used by clinicians and managers to build checklists and local roadmaps for local implementation of POM and for quality improvement initiatives. In addition, Table 1 summarises a number of specific pre-operative,52–63 intra-operative21,64,67–71 and postoperative64,72–80 clinical interventions that can be implemented locally for peri-operative optimisation of high-risk patients.
Regular feedback of outcome
National and local stakeholders should agree on specific outcomes that are prospectively assessed in all high-risk patients (quality indicators). The most frequently investigated patient-relevant outcome in high-risk patients is the postoperative mortality. Other relevant outcome indicators of POM are the rate of unplanned return to the operating room, unplanned ICU admission (including re-intubation and re-admission), peri-operative MAEs and failure to rescue rates.178 A critical follow-up with audit and regular feedback on these outcomes is a fundamental part of POM and quality improvement.
Local quality improvement programmes
Targeted quality improvement programmes may be particularly useful for increasing the quality of peri-operative care in situations with high error rates. This may apply to any of the peri-operative periods. For instance, if peri-operative diagnostic errors are frequent in the pre-operative consultation clinic with futile surgical interventions or underestimations of risks, then this consultation may require reorganisation. If high-risk patients are discharged early to surgical wards despite abnormal vital signs, the postanaesthesia care unit may need to implement quantitative instruments for discharge.
The implementation process of a quality improvement programme is crucial. During the planning phase, the multidisciplinary involvement of all stakeholders is essential, as well as the integration of feedback by local front-line providers.179 Experiences and results from local pilot implementation and champions (ideally volunteers) recruited from the local team with protected time for promotion and education will enhance adoption and engagement. The use of an established knowledge translation framework,180,181 a multisite project, and a reasonable, explicit timeline including actionable and quantifiable milestones have been reported to facilitate implementation.179,182 Consistent with most knowledge translation frameworks, iterative reassessment and readjustment cycles will improve the programme. The availability of local outcome data from registries will foster engagement among front-line professional and justify investments towards hospital management.179,182
Of note, in terms of risk assessment and efficient recovery, the ERAS concept has been shown to be successful in reduction of hospital length of stay for a number of procedures especially elective procedures with homogeneous patient groups. Many lessons can be learnt from such pathways and applied to all patient groups. For example, the implementation of peri-operative packages with stop-checks for the fulfilment of discrete elements of care and evidence-based care in postoperative care unit24,183 encourages a reduction in variation in healthcare delivery.
This is a narrative review aiming to help define a concept including medical and management aspects. The authors did not use a predefined search strategy and the evidence presented reflects the authors’ perspectives on POM. The review does not focus on a specific component of POM (e.g. risk assessment, pathways or definitions) and, therefore, it is not a systematic review. Specific components of POM should be investigated in regularly updated systematic reviews.184 This narrative review is an expert opinion report, and the authors are experienced senior researchers and educators in the field of POM and two of the authors are Editors of the European Journal of Anaesthesiology (MC and BW) having a broad and updated view on this topic. Some aspects related to POM are not covered in the present review, including education and training and future research.
POM is the patient-centered and value-based multidisciplinary peri-operative care of surgical patients. Frequent risk (re)-stratification during the peri-operative period using scores and biomarkers combined with allocation of patients to individualised risk-adapted predefined clinical pathways may decrease the occurrence of MAEs and improve outcomes. Peri-operative optimisation based on recent guidelines may further improve patient-relevant outcomes. Finally, regular audit and feedback are essential for assessing and adjusting performance.
Acknowledgements relating to this article
Assistance with the review: none.
Financial support and sponsorship: none.
Conflicts of interest: none.
Comment from the editor: MC is an Associate Editor of the European Journal of Anaesthesiology. BW is a Deputy Editor of the European Journal of Anaesthesiology.
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