Waterlow score as a surrogate marker for predicting adverse outcome in acute pancreatitis

Waterlow score for risk assessment in surgical patients: a systematic review

INTRODUCTION

The Waterlow score (WS) is used routinely in clinical practice to assess risk of pressure sore development. Recent studies have also suggested its use in preoperative risk stratification. The primary aim of this systematic review was to evaluate the current evidence on the WS in predicting morbidity and mortality in surgical patients.

METHODS

A systematic review was carried out in accordance with PRISMA and SWiM guidelines. A search strategy was conducted on the MEDLINE and EMBASE databases. Quality was assessed using the Newcastle-Ottawa scale.

FINDINGS

Overall, 72 papers were identified, of which 7 met inclusion criteria for full text review, and 4 were included for analysis. All studies were cohort in nature and published between 2013 and 2016, encompassing a total of 505 surgical patients. The studies included general, vascular, transplant and orthopaedic surgery. A high WS was demonstrated to have statistically significant association with increased morbidity and mortality as well as need for intensive care unit admission and length of stay. Furthermore, this was a more accurate predictor compared with the P-POSSUM and ASA scoring systems used currently in routine practice.

CONCLUSIONS

The WS is a promising tool for risk stratification of surgical patients. It is already collected routinely by nursing staff throughout hospitals in the UK and would therefore be easy to implement. However, further large prospective studies are required in order to validate these findings prior to its establishment for this role in everyday surgical practice.

Can Waterlow score predict 30-day mortality and length of stay in acutely admitted medical patients (aged ≥65 years)? Evidence from a single centre prospective cohort study

OBJECTIVE

This study aimed to explore the potential for the Waterlow score (WS) to be used as a predictor of 30-day mortality and length of hospital stay (LHS) in acutely admitted medical patients aged 65 years and older.

DESIGN

Prospective observational cohort study.

SETTING

UK District General Hospital.

SUBJECTS

834 consecutive patients aged 65 years and older admitted acutely to medical specialties between 30 May and 22 July 2014.

METHODS

Admission WS (range 4-64) assessment paired with the patient's status at 30 days in terms of mortality and their LHS.

PRIMARY OUTCOMES

30-day mortality and length of inpatient stay.

RESULTS

834 consecutive acute medical admissions had their WS recorded. 30-day mortality was 13.1% (109 deaths). A significant difference in the distribution of WS (p<0.001) was seen between those who survived (median 12) and those who died (median 16) within 30 days, particularly within respiratory (p<0.001), stroke (p<0.001), cardiology (p<0.016), non-respiratory infections (p<0.018) and trauma (p<0.044) subgroups. Odds of dying within 30 days increased threefold for every 10-unit increase in the WS (p<0.001, 95% CI 2.1 to 4.3). LHS was also positively linearly associated with the WS in those who survived 30 days (median=5, IQR=10; r=0.32, p<0.01). A five-unit increase in WS was associated with approximately 5 days increase in LHS. On the other hand, quadratic regression showed this relationship was curvilinear and negative (concave) for those who died within 30 days where a five-unit increase in WS was associated with an approximately 10 days decrease in LHS.

CONCLUSION

This study demonstrates an association between a high WS and both 30-day mortality and LHS. This is particularly significant for mortality in patients in the respiratory, stroke and cardiac subcategories. The WS, a nursing-led screening tool that is carried out on virtually all admissions to UK hospitals, could have additional use at the time of patient admission as a risk assessment tool for 30-day mortality as well as a predictor of LHS.