This is the first survey of Perioperative Medicine Leads in the UK to evaluate the structured screening, assessment and management of malnutrition in patients undergoing elective surgery. The response rate of 72.5% suggests the survey is sufficiently representative of current practice.
We found that whilst the majority of Perioperative Medicine Leads indicated that patients were routinely screened for malnutrition, nearly half lacked confidence that their trust had an effective process for ensuring that all surgical patients were screened and treated in the perioperative period. The majority of hospitals are reported to be using the Malnutrition Universal Screening Tool for screening patients; however, only half are reported to refer patients identified as being at nutritional risk onto a dietitian and less than a quarter have a structured pathway for managing malnourished patients pre-operatively.
The Perioperative Medicine Leads in this survey overwhelmingly agreed that malnutrition impacts on a patient’s quality of life after surgery, that structured pathways for managing malnourished patients would improve outcomes, and that perioperative clinicians have a role in its management. However, those that lacked confidence in their hospital’s ability to identify and manage malnutrition in the surgical patient cited a lack of organisational support, proximity of seeing patients to surgery, lack of clarity around responsibility and inadequate training and education as reasons they felt they could not manage this group. So how do we bridge this gap between what we think we should be doing and reality?
Screening for malnutrition
All patients having surgery should be screened for nutritional risk (National Institute for Health and Care Excellence
2017). It is the key first step in identifying those that may need additional support and is essential to avoid missing those who are malnourished without displaying overt symptoms. It is therefore surprising that only two-thirds of respondents stated the use of a screening tool validated for surgical patients. When a validated tool was used, this was almost exclusively MUST. Whilst MUST is recommended by the National Institute for Health and Care Excellence (NICE) for screening hospital and community patients, numerous other screening tools are available. For example, the Nutrition Risk Screening 2002 (NRS-2002) is recommended by European Society for Clinical Nutrition and Metabolism (ESPEN) (Weimann et al.
2017; Kondrup et al.
2003), yet only one respondent reported its use. Other examples include the Malnutrition Screening Tool, Short Nutritional Assessment Questionnaire and the recently developed Pre-operative Nutrition Score, which is a modification of MUST that also incorporates albumin (West et al.
2017). Regardless of which tool is being used, it is clear that the nutritional needs of some patients are not being appropriately addressed pre-operatively. We recommend that pre-operative pathways are mapped as a priority to identify the point of contemplation of surgery and that nutritional screening is performed as early as possible (Grocott et al.
2017). The screening tool used should be able to detect the presence of under-nutrition in an elective surgical population and should be standardised across all specialities to enable institution-wide consistency of practice.
Assessment of the patient at risk of malnutrition
Any patient identified at being at risk of malnutrition should undergo a diagnostic assessment involving the identification of phenotypic (non-volitional weight loss, low BMI, low muscle mass) and aetiological (reduced intake, disease burden/inflammation) criteria (Cederholm et al.
2019). Whilst some of these criteria are included in many screening tools, it is crucial to highlight that screening and assessment are temporally different processes and confusing the two may result in misdiagnosis and inappropriate treatment. With specific regard to muscle mass, virtually no anthropometric or body composition assessments appear to be being performed in patients identified at nutritional risk. This finding is important as patients with higher lean body mass cope better with surgery, have fewer complications and spend less time in hospital (Kyle et al.
2005; Pichard et al.
2004; Van Venrooij et al.
2012).
Disease burden and inflammation are harder to objectively define. In the absence of a better test hypo-albuminaemia (albumin < 30g/l without hepatic or renal dysfunction) may be the best biochemical marker currently available and was used by nearly two-thirds of those surveyed. It is important that the perioperative clinician is aware that albumin reflects disease severity and related catabolism, and is not a direct measure of malnutrition. However, it is prognostic for complications and recommended by ESPEN for use in surgical patients (Weimann et al.
2017).
Assessment of patients should ideally be undertaken by those with accredited professional training in nutrition, such as a registered dietitian or physician with specific responsibility for clinical nutrition. However, current dietetic resources are largely directed to supporting patients after surgery. Outside of specialities where there is a high risk of malnutrition, such as upper gastro-intestinal cancer, pathways for pre-operative optimisation may be under-resourced and lack specialist dietitian input. It was, therefore, unsurprising that only half of those identified to be at risk received onward referral to a dietitian, with the remainder seeing either a variety of other professions or no one at all. This variability will be multi-factorial and may reflect an under-resourced, unstructured, pathway. In keeping with this, less than half of Perioperative Medicine Leads reported having a pathway for managing malnourished patients despite the vast majority agreeing this would improve outcomes. One solution to better direct the use of available resources may lie in formalising pathways and re-engineering the patient’s perioperative journey such that those at risk are identified at the time of referral for surgery, assessed earlier, with sufficient time then afforded to the interventions required to improve modifiable risk factors such as malnutrition (Grocott et al.
2017).
Management of malnourished patients pre-operatively
The aims of treatment of a malnourished surgical patient are to improve nutritional status, limit wasting and ultimately maximise resilience and functional recovery. Where this cannot be achieved by dietary advice and food alone, nutritional support may be required (oral nutritional supplements (ONS), enteral tube feeding and/or parenteral nutrition). We did not examine enteral tube feeding or parenteral nutrition but did explore ONS as this is a simple intervention that can be actioned pre-operatively. NICE recommends considering ONS in those who are malnourished or at risk of malnutrition (National Institute for Health and Care Excellence
2017) as ONS has consistently been shown to increase intake (Sobotka
2010), reduce post-operative complications (Waitzberg et al.
2006) and be cost-effective (Elia et al.
2016). ESPEN goes further, suggesting it to be obligatory for all malnourished cancer and high-risk surgical patients and patients not receiving adequate intake through normal food (Lobo et al.
2020). Given this, we were surprised that less than half of Perioperative Medicine Leads report that their hospital prescribes ONS for malnourished patients. When considering implementing ONS into a nutritional care plan, it should be noted that patients need to be educated about its benefits and consideration given to the provision of energy-dense (> 2 kcal/ml) formulations, as both improve compliance (Grass et al.
2015).
So how can we improve the care we provide for this group of patients? Screening, assessing and managing these patients is important because malnutrition is one of the few modifiable pre-operative risk factors that, if addressed early and treated appropriately, can affect post-operative outcomes (Stratton and Elia
2007; Jie et al.
2012; Garth et al.
2010). Malnutrition is under-recognised and under-treated (British Association of Parenteral and Enteral Nutrition
2009; Marcos et al.
2003). It causes increased postoperative morbidity, excess mortality and increased costs (Weimann et al.
2017; Schneider et al.
2004; Sorensen et al.
2008). Cancer patients are at particular risk due to the effects of malignancy on nutrient metabolism and delays in surgery due to the side-effects of neo-adjuvant treatments (Andreyev et al.
1998). As a case in point, a recent study of patients undergoing colorectal cancer surgery found that malnourished patients were more likely to be readmitted within 30 days (Gillis et al.
2015).
There are numerous issues highlighted by this survey, some easier to remedy than others. It is noteworthy that many are common to previous work undertaken in Europe and North America, adding to the evidence that this is a key area for improvement (Grass et al.
2011; Williams and Wicschmeyer,
2017). Screening is a simple intervention and we encourage all Perioperative Medicine Leads to introduce a standardised tool early in the surgical pathway as a priority, as the first stage of identifying the size of this unmet need. Ideally, all patients identified as at risk should be assessed by a dietitian, although there may be significant resource implications if hospital dietitians are primarily focused on in-hospital patients. Early identification is essential to ensure sufficient time for optimisation without delaying surgery. Involving dietitians in the development of standardised pre-operative pathways will facilitate the multidisciplinary teamwork and data collection required to ensure an adequately resourced service. An example of a potential solution may be the development and implementation of perioperative nutrition clinics (Williams et al.
2020), though further work is needed to assess feasibility in the UK healthcare setting.
Looking to the future, technology and advances in therapies should be embraced to improve the way we assess and manage perioperative malnutrition. Examples include using bioelectrical impedance analysis, cross-sectional imaging or ultrasound to assess muscle mass (Williams et al.
2019), for nutrition risk scores to be transferred seamlessly between primary and secondary care and for patients to take responsibility for their own nutritional health through the use of smart device applications. Nutrition therapy is also a key component of multi-modal prehabilitation, recently advocated for all people with cancer, alongside psychological and exercise interventions (Macmillan Cancer Support
2019). Nutritional prehabilitation alone or combined with exercise reduces length of stay by 2 days in colorectal cancer surgery patients and may result in faster return to pre-operative fitness (Gillis et al.
2018). The results of larger randomised controlled trials are awaited.
One of the main strengths of this study is the high response rate, implying it is representative of current practice. We focused on the areas of nutritional evaluation that are clearly within the domain of Perioperative Medicine Leads, namely standardised screening, pathway management and barriers to care rather than focusing on areas of specific dietetic expertise. As such, our findings are most relevant to the perioperative clinician seeing patients prior to elective surgery in the pre-assessment clinic. However, our study has weaknesses. We relied on Perioperative Medicine Leads being able to discuss questions with other members of the multi-disciplinary team, which may not have occurred. Furthermore, whilst we believe that Perioperative Medicine Leads should be aware of local polices and nutritional services available in their hospital, this may not always be the case.
In conclusion, we report that there are deficiencies in the screening, assessment and optimisation of nutritional status prior to elective surgery in the UK. There is an urgent need to implement standardised pathways to ensure the optimisation of a risk factor that we know is amenable to intervention in a realistic pre-operative time frame and that has important impact on surgical outcomes.