BJA Advance Access originally published online on October 24, 2007
British Journal of Anaesthesia 2007 99(6):809-811; doi:10.1093/bja/aem305
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Preoperative shuttle walking testing and outcome after oesophagogastrectomy
1 Department of Anaesthesia and Critical Care
2 Upper Gastrointestinal Surgery
3 Respiratory Physiology, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, UK
* Corresponding author. E-mail: paul.murray{at}sth.nhs.uk
Accepted for publication April 22, 2007.
 |
Abstract |
|---|
 Top Abstract IntroductionMethodsResultsDiscussionAppendixReferences |
|---|
Background: Objective assessment of cardiorespiratory reserve has been recommended before major surgery to identify patients with impaired oxygen delivery who may be at increased operative risk. Access to formal cardiopulmonary exercise (CPX) testing is limited outside larger centres. Following a previous audit of morbidity and mortality after oesophagectomy, we decided to add a simpler form of exercise test to our preoperative screen and review the outcomes.
Methods: Fifty-one patients who had surgical resection of an oesophageal cancer in our unit between April 2002 and April 2005 carried out an incremental shuttle walk exercise test before operation. Thirty-day outcome data were collected for each patient.
Results: Overall mortality in the group was 10%. No patient who walked 350 m or more died within 30 days. Five of the eight patients who could not achieve this distance died and two others remained in the critical care unit at 30 days.
Conclusion: Preoperative shuttle walk testing using a standard protocol appears to be a sensitive indicator of operative risk in this group of patients. The apparent threshold value of 350 m is consistent with previously reported measures of functional capacity obtained using formal CPX testing.
Keywords: assessment, preanaesthetic; metabolism, oxygen consumption; oxygen, uptake
|
Introduction |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionAppendixReferences |
|---|
Many patients presenting to surgical teams with oesophageal cancer have significant pre-existing co-morbidity. This co-morbidity is a major predictor of postoperative complications and death.1
Major surgery places significant metabolic demands upon patients. The oxygen consumption increases by up to 50% in the immediate postoperative period, necessitating a significant increase in cardiac output and oxygen delivery. Patients unable to meet this metabolic demand may be at increased postoperative risk.2 3
Exercise testing has previously been shown to provide an objective and reproducible assessment of cardiac and respiratory reserve before major surgery. Using formal cardiopulmonary exercise (CPX) testing involving cycle ergometry, ECG monitoring, and expired gas analysis, Older and colleagues4 demonstrated a clear relationship between preoperative functional reserve, defined by anaerobic threshold, and operative risk. In June 2005, on the basis of this and other reports, the Improving Surgical Outcomes Group recommended the use of CPX before high-risk surgery.5 Formal cardiopulmonary testing is a relatively expensive and time-consuming procedure, which may not be available outside specialist centres.
The incremental shuttle walk test (SWT) is a simple, reproducible test that has been widely used in the assessment of patients with cardiac failure and pulmonary diseases.6 Distance achieved in an SWT correlates well with measures of oxygen uptake obtained through formal CPX testing.7 Following an earlier audit of morbidity and mortality after oesophagectomy, we incorporated an SWT into our preoperative screening protocol. In this audit, we aimed to assess the usefulness of SWT in predicting outcome after oesophagogastrectomy.
|
Methods |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionAppendixReferences |
|---|
An approval of local ethics committee was obtained to incorporate SWT into preoperative screening tests for patients undergoing oesophagogastrectomy. Between April 2002 and April 2005, 93 patients had an oesophagogastrectomy at the Royal Hallamshire Hospital, Sheffield. Service reconfiguration onto a single site during 2004 interrupted data collection, resulting in only 51 of these 93 patients completing an SWT before operation. The tests followed a standard protocol, subjects walking at increasing speed up and down a 10 m course marked out by two cones until unable to keep pace with a pre-recorded beep played on a tape recorder.6 Heart rate and oxygen saturation were monitored using a portable oximeter. A self-reported weighted Duke activity questionnaire was completed by 34 of the 51 patients who undertook the SWT.8
The primary assessment was the 30th day outcome of the 51 patients who performed an SWT before an oesophagogastrectomy. Data are expressed in terms of distance covered during SWT and mortality. Pearson’s coefficient of correlation was calculated for the relationship between SWT distance and Duke’s Activity Score.
|
Results |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionAppendixReferences |
|---|
Among the 51 patients included in this audit, the distance covered during SWT ranged between 220 and 880 m (median 470 m). Overall mortality rate was 10% for the SWT cohort and 9% in the entire group of 93 patients, comparable with the UK mortality rate quoted by McCulloch and colleagues1 of 12% in 2003.
No patient who achieved an SWT distance greater than 340 m died within this period (n=43) (Table 1).
|
Five of the eight patients with a measured SWT of 340 m or less died within 30 postoperative days (median 300 m, range 280–340 m). The average age of those who died was 72 yr and those who survived 63 yr. There was a poor, although statistically significant, correlation (coefficient of correlation 0.433, P<0.01) between the SWT distance achieved and the Duke Activity Score in our cohort (Fig. 1).
|
|
Discussion |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionAppendixReferences |
|---|
The utility of shuttle walk exercise testing has been recognized for some years by medical and surgical teams tracking disease progress in patients awaiting heart or lung transplantation. The test, although usually performed in a respiratory function laboratory, does not require sophisticated equipment or medical supervision. Shuttle walk testing, being symptom limited, correlates better with measures of anaerobic threshold obtained via CPX than time limited non-maximal tests such as the 6 min walk. Older’s 1993 paper, demonstrating the value of preoperative CPX testing in high-risk surgical populations, continues to provoke interest and was the basis of the recommendation in the 2005 Modernising Care for Patients Undergoing Major Surgery report that objective assessment of functional reserve be incorporated into new standards of preoperative care in the UK.5
Our audit has generated an incomplete data set, only 51 of 93 patients performing a preoperative SWT, and only 34 of those completing a Duke questionnaire. We did not prospectively collect demographic data or record specific pre- and perioperative morbidities or details of surgical technique. The principal outcome, mortality, was comparable in the SWT and non-SWT groups, however (and also with published national mortality rates), suggesting that our patient sample was representative.
This rudimentary study suggests that shuttle walk testing may be a useful alternative to CPX, the apparent discriminative value of 350 m in our population approximating to Older’s anaerobic threshold of 11 ml min–1 kg–1. There is a considerable co-morbidity in this surgical population, the mean of all SWT completed by our patient group being 489 m, less than the 503 m achieved by Morales’ group of stable heart failure patients.7 This co-morbidity was not evident, however, in subjective estimates of exercise capacity, with poor correlation between SWT and Duke Activity Scores and a wide variation in score at the 350 m threshold, reflecting perhaps the limitations of self-reported data in this setting. Patients with limited functional reserve may be unable to maintain adequate oxygen delivery to permit surgical wound healing, anastamotic failure being a common, and often catastrophic, early complication in this population.
Current practice in our unit incorporates an SWT early in the staging process after referral. A borderline exercise test prompts further assessment for reversible factors impairing oxygen delivery. Heart rate and oxygen saturation before and during the test may provide an indication of underlying pathology. Nutritional supplements, smoking cessation, and encouragement to exercise can improve SWT performance over a few weeks before surgery. In cases where staging reveals advanced disease, a poor SWT can facilitate informed discussion between patient and medical team regarding operative risk and alternative treatment plans.
Further study is now required to validate this approach in this and other high-risk surgical groups. The morbidly obese or those with degenerative joint disease or vascular insufficiency may have difficulty completing an SWT or CPX; in some circumstances upper limb ergometry will provide helpful data and can be a useful training technique to improve preoperative fitness.
|
Appendix |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionAppendixReferences |
|---|
Details of all the patients who underwent an SWT
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
References |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionAppendixReferences |
|---|
1 McCulloch P, Ward J, Tekkis PP, et al. Mortality and morbidity in gastro-oesophageal surgery. Br Med J (2003) 327:1192–7.
2 Older P, Smith R. Experience with the preoperative invasive measurement of haemodynamic, respiratory and renal function in 100 elderly patients scheduled for major abdominal surgery. Anaesth Intensive Care (1988) 16:389–95.[Web of Science][Medline]
3 Kusano C, Baba M, Takao S, et al. Oxygen delivery as a factor in the development of fatal postoperative complications after oesophagectomy. Br J Surg (1997) 84:252–7.[CrossRef][Web of Science][Medline]
4 Older P, Smith R, Courtney P, Hone R. Preoperative evaluation of cardiac failure and ischaemia in elderly patients by cardiopulmonary exercise testing. Chest (1993) 104:701–4.[CrossRef][Web of Science][Medline]
5 Improving Surgical Outcomes Group. Modernising Care For Patients Undergoing Major Surgery (2005) Available from reducinglengthofstay.org.uk.
6 Singh SJ, Morgan MDL, Scott S, Walters D, Hardmann AE. The development of the shuttle walk test of disability in patients with chronic airway obstruction. Thorax (1992) 47:1019–24.
7 Morales F, Martinez A, Mendez M, et al. A shuttle walk test for the assessment of functional capacity in chronic heart failure. Am Heart J (1999) 138:291–8.[CrossRef][Web of Science][Medline]
8 Hlatky MA, Boineau R, Higginbotham M, et al. A brief self administered questionnaire to determine functional capacity—the Duke Activity Status. Am J Cardiol (1989) 64:651–4.[CrossRef][Web of Science][Medline]
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  L. Powell, G. Hood, and A. Wyman Gastrectomy for adenocarcinoma CEACCP, April 1, 2009; 9(2): 65 - 69. [Full Text] [PDF]
|
|
|
|
 |
|
 R. Struthers, P. Erasmus, K. Holmes, P. Warman, A. Collingwood, and J. R. Sneyd Assessing fitness for surgery: a comparison of questionnaire, incremental shuttle walk, and cardiopulmonary exercise testing in general surgical patients Br. J. Anaesth., December 1, 2008; 101(6): 774 - 780. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. S. Reilly Can we accurately assess an individual's perioperative risk? Br. J. Anaesth., December 1, 2008; 101(6): 747 - 749. [Full Text] [PDF]
|
|
|
|
|
|
C. M. Danbury, S. O'Neill, A. Kitching, P. Murray, and (on behalf of the authors) Preoperative cardiopulmonary exercise testing Br. J. Anaesth., May 1, 2008; 100(5): 726 - 726. [Full Text] [PDF]
|
|
E-letters:
Read all E-letters
- Pre-operative CPX testing
- Chris M Danbury, et al.
- British Journal of Anaesthesia, 10 Jan 2008 [Full text]
- Response
- PAUL MURRAY
- British Journal of Anaesthesia, 12 Feb 2008 [Full text]
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||