Abstract
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:
To assess the effect of CGA interventions compared to standard care on the postoperative outcomes of older patients admitted to hospital for care.
Background
This review will assess the effects of Comprehensive Geriatric Assessment (CGA) on postoperative outcomes of elderly patients admitted to hospital with a surgical problem.
Description of the condition
As the world's population ages, the demand for surgery among the elderly is increasing (Etzioni 2003). It is estimated that over half of all operations are performed on people over the age of 65 (Geriatric Review Syllabus 2006). Compared to their younger counterparts, older patients experience higher rates of postoperative complications, have a longer length of stay in hospital, and are more likely to require institutionalisation after discharge (Lidsky 2012; Turrentine 2006). The increased costs and health resource use associated with older surgical patients will place a tremendous strain on the healthcare system, highlighting the need for evidence‐based interventions that can improve the outcomes of this patient population (Etzioni 2011).
Description of the intervention
CGA is a "multidisciplinary diagnostic process intended to determine a frail elderly person's medical, psychosocial, and functional capabilities and limitations in order to develop an overall plan for treatment and long‐term follow‐up" (Rubenstein 1991). CGA is not any one intervention in isolation, but rather a co‐ordinated, multidisciplinary collaboration. This has already been successfully demonstrated on medical and orthogeriatric units (Ellis 2011; Frondini 2010; Prestmo 2015). Aspects of CGA are organised into three categories (medical, psychosocial, and functional) and may include a combination of the following factors (Rubenstein 1989).
Medical
Primary diagnosis resulting in admission.
Geriatrician following every eligible patient during their admission.
Minimising the use of medications prone to causing delirium and adjusting dosing for geriatric syndromes.
Comprehensive medication review by pharmacist.
Psychosocial
Environmental cues to orient patient.
Regular comfort rounds by nursing staff.
Early discharge planning to anticipate and manage potential challenges.
Functional
Fall risk assessment and mitigation.
Physiotherapist intervention to prevent neuromuscular deconditioning.
Occupational therapist to identify and manage barriers to independence.
Physical environment modifications to reduce confusion, falls, delirium.
These interventions are conducted within a multidisciplinary collaboration to develop a unified plan of care for the elderly patient and will be compared with usual care in a standard inpatient ward. CGA can be delivered at any point in a patient's care for elective surgical interventions, but can only be delivered postoperatively for emergency procedures. It is unclear if geriatric interventions before and after surgery are equally effective or if the interventions produce different effects in elective versus emergency surgery.
How the intervention might work
Older surgical patients have complex healthcare needs: frailty, multimorbidity, and polypharmacy are common in this patient population (Bettelli 2011). However, most hospitals are structured to care for patients with a single, acute illness and are often ill equipped to meet the needs of older patients, leading to poor surgical outcomes. By performing a CGA, healthcare providers can identify and optimise medical and social issues associated with surgical complications before they have a negative impact on the health of the patient, which could improve outcomes.
Why it is important to do this review
Previous studies, notably Ellis and colleagues’ 2011 Cochrane review examining the effect of CGA on medical patient outcomes (Ellis 2011), have been promising, showing CGA interventions to be associated with a decrease in death or deterioration, improved cognitive function, and less institutionalisation. However, most studies have focused on patients admitted to hospital with general internal medicine issues, and to date there have not been any systematic reviews of CGA interventions focusing only on surgical patients. There has also been no attempt to evaluate the role of timing of CGA and surgery on the effectiveness of the intervention.
Objectives
To assess the effect of CGA interventions compared to standard care on the postoperative outcomes of older patients admitted to hospital for care.
Methods
Criteria for considering studies for this review
Types of studies
We will only include randomised controlled trials of postoperative patients from all surgical specialties, including emergency and elective surgery, receiving a CGA intervention compared with a control group receiving standard care. To reduce the likelihood of publication bias, we will not limit included articles to the English language, and we will screen articles from trial databases and the grey literature for eligibility.
Types of participants
The focus of this review will be people age 65 years or older in hospital under the care of an inpatient surgical ward. Although there is not a standard numerical criteria to define old age, 65 years old is widely accepted as the chronological age to be considered an older person.
People admitted to hospital for elective or emergency surgery, or for an acute medical condition or injury requiring close observation and expectant management by a surgical team, will be eligible for inclusion in the analysis.
Studies containing a subset of surgical patients above the age of 65 will be eligible for inclusion; however, only study data pertaining to our population of interest will be included in the meta‐analysis.
Types of interventions
We will include studies in which a geriatrician, internist, hospitalist, or geriatric nurse has performed a multicomponent geriatric assessment in hospital, and in which patients receiving the intervention were compared with patients receiving standard postoperative care. The CGA intervention can be performed as part of a mobile, multidisciplinary team consulted to provide patient management recommendations, or as part of a specialised ward dedicated to providing multidisciplinary care to geriatric surgical patients. The CGA intervention may be carried out preoperatively, postoperatively, or throughout the patient's stay in hospital.
We will exclude studies in which CGA was used only as a tool to predict adverse postoperative events. We will also exclude studies examining only one aspect of the CGA instead of employing a multidimensional assessment, and we will exclude cross‐over studies. We will exclude enhanced recovery after surgery programmes because CGA is not a routine component of these programmes.
Types of outcome measures
Primary outcomes
The primary outcomes to be assessed will be mortality and discharge destination.
We will measure mortality as a dichotomous outcome to the end of follow‐up after treatment. We will measure discharge destination as a dichotomous outcome reported as patients returning to their pre‐admission place of residence versus being discharged to an increased level of care such as an assisted‐living or long‐term care facility.
Secondary outcomes
Secondary outcomes will include postoperative complication rates, length of stay, readmission rate, and cost.
Postoperative complications will include any of the following events in hospital after surgery: intensive care unit admission, vascular complications (e.g. myocardial infarction, stroke, deep venous thrombosis, and pulmonary embolism), serious infection, and delirium. For studies that do not report major‐complication categories, we will record complication frequency by organ system (e.g. cardiovascular, respiratory, gastrointestinal, neurologic, etc.). We will report all complications as a dichotomous (yes or no) outcome. Complications that are not prone to detection bias, such as stroke and myocardial infarction, and those detected in studies with appropriate blinding of complication assessment, will be more strongly weighted in the discussion. Delirium is particularly prone to detection bias due to the CGA intervention; we will assess how each study controls for this.
We will measure length of stay as a continuous outcome reported as the number of days spent in hospital after surgery. We will measure readmission as a dichotomous outcome. Cost will be presented in euros for 2016 after converting using Purchasing Power Parity (PPP) and the Gross Domestic Product (GDP) inflator as per the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011), but will not be combined due to cross‐jurisdictional differences in cost reporting and variation in data sources.
Search methods for identification of studies
Electronic searches
We will use a sensitive search strategy designed to retrieve studies from electronic databases. We will search the following databases, with publication dates ranging from inception to search date.
Cochrane Central Register of Controlled Trials (CENTRAL), including the Cochrane Effective Practice and Organisation of Care (EPOC) Group Specialised Register, part of the Cochrane Library (www.cochranelibrary.com)
MEDLINE In‐Process & Other Non‐Indexed Citations, OvidSP (1946 ‐ )
Embase, OvidSP (1974 ‐ )
PsycINFO, OvidSP (1987‐ )
CINAHL (Cumulative Index to Nursing and Allied Health Literature), EBSCO (1980 ‐ )
The search terms will combine Medical Subject Headings (MeSH) and free text words as shown in the MEDLINE strategy in Appendix 1. The MEDLINE strategy will be translated using appropriate syntax and controlled vocabulary headings for other databases. We will not place any restrictions on language, publication type, or publication year.
Searching other resources
We will conduct a grey literature search to identify non‐indexed studies not appearing in the databases listed above. Sources will include:
World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) (www.who.int/ictrp/en/); and
US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov (clinicaltrials.gov).
We will use Science Citation Index to search the cited and citing articles of included studies.
Data collection and analysis
Selection of studies
Two review authors will screen titles and abstracts to identify potentially eligible articles for full‐text review. We will assess potential eligibility based on design, participants, intervention, and outcomes as described. We will exclude studies that do not meet the inclusion criteria at this stage. Two review authors will independently carry out full‐text review. We will resolve conflicts between review authors at all stages of article screening and data extraction by discussion and consensus. We will report the number of studies excluded in the title and abstract review and the full‐text review. We will report articles that appeared relevant to the review question, but were excluded from analysis, with the reasons for exclusion as per Section 7.2.5 of the Cochrane Handbook (Higgins 2011).
Data extraction and management
Two review authors will independently extract data onto web‐based electronic data collection forms (Covidence.org). Disagreements between review authors will be resolved by discussion and consensus. We will translate included articles not published in English using available software prior to data extraction. We will then export data to Review Manager 5 for analysis (RevMan 5.3).
During data extraction, review authors will take note of the study source, eligibility, methods, participants, interventions, outcomes of interest, results, and other information as defined in Table 7.3.a of the Cochrane Handbook, in Higgins 2011, and the EPOC good‐practice data extraction form (EPOC 2015a). We will report all costs in euros.
Assessment of risk of bias in included studies
Two review authors will independently assess risk of bias using Cochrane's 'Risk of bias' tool (Higgins 2011), with modifications based on the EPOC guidance for risk of bias criteria (EPOC 2015b). We will evaluate each study using a bias assessment tool, rating each of the following criteria for each study as low risk, high risk, or uncertain risk.
Random sequence generation ‐ was the allocation sequence adequately generated.
Allocation concealment ‐ was allocation concealment adequate.
Baseline demographics between groups ‐ were baseline outcomes measured before the intervention and were they similar between groups.
Incomplete data ‐ were loss to follow‐up or dropouts low enough to limit risk of bias.
Blinding of participants and personnel ‐ were participants and personnel blind to the intervention.
Blinding of outcome assessment ‐ were outcome assessors blind to the intervention.
Protection from cross‐contamination ‐ were there safeguards to cross‐contamination of the control group.
Selective reporting ‐ were all outcomes in the methods reported in the results.
Other risks of bias ‐ were any additional risks noted during bias assessment.
Measures of treatment effect
We will report dichotomous outcome data such as the effect of CGA on patient mortality and discharge destination as risk ratios with 95% confidence intervals. We will report continuous outcome data such as the effect of CGA on length of stay using the mean difference between the CGA intervention and standard care with a 95% confidence interval. For all continuous‐variable outcomes, we will report the mean and standard deviations or standard error of the outcome measurements in each intervention group, as well as the number of participants on which the outcome was measured.
Unit of analysis issues
We will perform analyses at the participant level to avoid unit of analysis errors. If we identify cluster randomised controlled trials, we will use a ratio estimator approach to reduce the size of each cluster trial to its effective sample size (Rao 1992), which is its original sample size divided by design effect. The design effect is 1 + (M – 1) ICC, where M is the average cluster size and ICC is the intracluster correlation coefficient. For dichotomous data, the number of participants and the number of events will be divided by the design effect. For continuous data, the sample size will be divided by the design effect. Missing ICCs may be selected from other cluster randomised controlled trials included in the review or obtained from similar external studies. We will conduct sensitivity analyses to investigate whether removing clustered trials affects the conclusions.
If the results of a study cannot be adjusted for the unit of analysis error, we will exclude it from the pooled analysis. We will pool data based on time since admission to discharge and end of follow‐up as predefined outcome measurement points.
Dealing with missing data
Where feasible, we will obtain missing data from authors. We will investigate attrition rates (e.g. dropouts, losses to follow‐up, and withdrawals), and critically appraise issues of missing data and imputation methods (e.g. last observation carried forward). Where standard deviations for outcomes are not reported, we will impute these values by assuming the standard deviation of the missing outcome to be the average of the standard deviations from those studies where this information was reported. We will investigate the impact of imputation on meta‐analyses by means of sensitivity analysis.
Assessment of heterogeneity
Where studies are considered similar enough based on population, study design, and setting to allow pooling of data using meta‐analysis, we will assess the degree of heterogeneity by visual inspection of forest plots and by examining the Chi2 test for heterogeneity. We will quantify heterogeneity between studies using the I2 test. An I2 of less than 40% will be considered unimportant; 40% to 60% may indicate moderate heterogeneity; 60% to 75% may indicate substantial heterogeneity; and 75% to 100% will indicate considerable heterogeneity. Where we detect substantial clinical, methodological, or statistical heterogeneity across included studies, we will not retain the pooled results from meta‐analysis but will instead use a narrative approach to data synthesis.
Assessment of reporting biases
Where information from 10 or more studies is available, we will generate a funnel plot to look for asymmetry. Where asymmetry exists, we will assess the reason for asymmetry based on Section 10.4 of the Cochrane Handbook (Higgins 2011).
We will assess publication bias by searching trial registries and the grey literature. For studies published after 1 July 2005, we will note lack of registration of the trial protocol with the WHO ICTRP in the 'Risk of bias' table. We will also note selective reporting of predefined outcomes.
Data synthesis
We will compare random‐effects and fixed‐effect models to assess if smaller studies affect the results. Given the complex and multidimensional nature of CGA, variation is expected in measured outcomes due to sampling error and differing patterns of implementation of CGA. If there is a difference between fixed‐effect and random‐effects models, we will assess the impact of small studies on the estimate of effect before deciding which model to use.
Summary of findings
We will summarise the findings of the main intervention comparison for the most important outcomes included in the review. We will grade our primary outcomes (mortality and discharge destination) and secondary outcomes (postoperative complication rates, length of stay, readmission rate, and cost) as a means to assess the certainty of the evidence. Two review authors will independently assess the certainty of the evidence (high, moderate, low, and very low) using the five GRADE considerations (study limitations, consistency of effect, imprecision, indirectness, and publication bias). We will use methods and recommendations described in Section 8.5 and Chapter 12 of the Cochrane Handbook (Higgins 2011), the EPOC worksheets (EPOC 2015a), and the GRADE Working Group guidelines (Guyatt 2008), and we will use GRADEpro software to grade each outcome (GRADEpro). We will resolve disagreements on certainty ratings by discussion and provide justification for decisions to down‐ or upgrade the ratings using footnotes in a 'Summary of findings' table, making comments to aid readers' understanding of the review where necessary.
Subgroup analysis and investigation of heterogeneity
We will conduct subgroup analysis for the a priori defined variables listed below.
Orthopaedic versus other surgical specialties.
CGA timing ‐ is the CGA conducted preoperatively, postoperatively, or throughout an admission.
Emergency versus elective surgery.
We will analyse these subgroups at discharge and end of follow‐up. We will determine if the subgroups differ significantly by inspecting the overlap of confidence intervals and testing for subgroup differences using Review Manager 5 (RevMan 5.3).
Timing of the CGA in relation to surgery could affect patient outcomes because the potential benefits of CGA intervention could arise from optimising patient medical and social issues before surgery; by providing a better level of care following surgery; or both pre‐ and postoperative intervention may be necessary to see benefits. Most studies of CGA in surgical patients have been performed in orthopaedic trauma (hip fracture); the effect of CGA may play an important role in recuperation from hip surgery but not in other surgical interventions or populations. Finally, elective versus emergency surgery can give rise to different risk profiles. Determining if there is a benefit in one population versus another is important.
Sensitivity analysis
We will perform sensitivity analysis to explore changes in effect size after removing studies with a high risk of bias and comparing the use of a fixed‐effect and random‐effects model.
Acknowledgements
As part of the pre‐publication editorial process, this protocol has been commented on by Graham Ellis, Julia Worswick, Kristoffer Yungpeng Ding, Paul Miller, and Sasha Shepperd. We thank them for their valuable contribution to the protocol. We would like to thank Liz Dennett and Paul Miller for reviewing and providing excellent feedback on the search strategy.
National Institute for Health Research, via Cochrane Infrastructure funding to the Effective Practice and Organisation of Care Group. The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the Systematic Reviews Programme, National Institute for Health Research, National Health Service, or the Department of Health.
Appendices
Appendix 1. MEDLINE search strategy
1. Geriatric Assessment/ 2. geriatric assessment*.tw,kf. 3. Health Services for the Aged/ 4. or/1‐3 5. comprehensive health care/ 6. Patient Care Planning/ 7. Progressive Patient Care/ 8. patient care team/ 9. patient‐centered care/ 10. "delivery of health care, integrated"/ 11. or/5‐10
12. (frail* or sarcopeni* or elder* or senior* or gerontolog* or geriatric* or veteran* or (old* adj (people or person* or resident* or adult* or patient*))).tw,kf. 13. 11 and 12 14. limit 11 to "all aged (65 and over)" 15. 4 or 13 or 14
16. ((frail* or sarcopeni* or elder* or senior* or gerontolog* or geriatric* or veteran* or old* people or old* person* or old* resident* or old* adult* or old* patient*) adj3 (assess* or evaluat* or apprais* or function or functioning or comprehensive* or patient care team or patient* education or interprofession* or inter‐profession* or interdisciplin* or inter‐disciplin* or multi‐disciplin* or multidisciplin* or rehab*)).tw,kf. 17. ((frail* or sarcopeni* or elder* or senior* or gerontolog* or geriatric* or veteran* or old* people or old* person* or old* resident* or old* adult* or old* patient*) adj3 (manage* care program* or Critical Pathway* or Program* Evaluation or case manag*)).tw,kf. 18. (geriatric adj3 (evaluation or management or program* or modif* or friendly or intervention or coordinat* or co‐ordinat*)).tw,kf. 19. (elder* adj3 (program* or modif* or friendly or intervention* or coordinat* or co‐ordinat*)).tw,kf. 20. or/16‐19
21. 15 or 20 22. exp Specialties, Surgical/ 23. exp surgical procedures, operative/ 24. su.fs. 25. Surgery Department, Hospital/ 26. perioperative care/ or intraoperative care/ or perioperative nursing/ or postoperative care/ or preoperative care/ 27. Trauma Centers/ or General Surgery/ 28. (((surgery or surgical) adj (unit* or department* or area*)) or (operating adj (room* or theatre* or theater* or suite*))).mp. 29. (surgery or surgical or trauma or operation or operating or operative).ti. 30. (surgery or surgical or trauma or operation or operating or operative).kf. 31. (surgery or surgical or trauma or operation or operating or operative).ab. /freq=2 32. (perioperative or peri operative or intraoperative or intra operative or postoperative or post‐operative).ti,ab,kf. 33. or/22‐32
34. (surgery or surgical or trauma or operation or operating or operative).mp. 35. hospital*.mp. 36. 34 and 35 37. 33 or 36 38. (acute care for elders or acute care for the elderly or Nurses Improving Care for Healthsystem Elders or modified Hospital Elder Life Program or mHELP or hospitali?ed elder life program*).tw,kf. 39. (geriatrician* or geriatric specialist* or geriatric nurse* or geriatric physician*).tw,kf. 40. (geriatric unit* or geriatric ward*).tw,kf. 41. 39 or 40 42. 37 and 41 43. 21 and 37 44. geriatric trauma*.mp.
45. 42 or 43 or 44 46. randomized controlled trial.pt. 47. controlled clinical trial.pt. 48. multicenter study.pt. 49. pragmatic clinical trial.pt. 50. (randomis* or randomiz* or randomly).ti,ab. 51. groups.ab. 52. (trial or multicenter or multi center or multicentre or multi centre).ti. 53. (intervention? or effect? or impact? or controlled or control group? or (before adj5 after) or (pre adj5 post) or ((pretest or pre test) and (posttest or post test)) or quasiexperiment* or quasi experiment* or pseudo experiment* or pseudoexperiment* or evaluat* or time series or time point? or repeated measur*).ti,ab. 54. non‐randomized controlled trials as topic/ 55. interrupted time series analysis/ 56. controlled before‐after studies/ 57. or/46‐56
58. exp animals/ 59. humans/ 60. 58 not (58 and 59) 61. review.pt. 62. meta analysis.pt. 63. news.pt. 64. comment.pt. 65. editorial.pt. 66. cochrane database of systematic reviews.jn. 67. comment on.cm. 68. (systematic review or literature review).ti. 69. or/60‐68 70. 57 not 69 71. 45 and 70 72. remove duplicates from 71
History
Protocol first published: Issue 1, 2017
| Date | Event | Description |
|---|---|---|
| 7 June 2016 | Amended | Citations have been added for GRADEpro and other minor improvements to citations. |
| 7 June 2016 | Amended | References conform to Cochrane guidelines. |
| 7 June 2016 | Amended | Bias assessment has been updated. |
| 7 June 2016 | Amended | PRISMA chart has been updated/incorporated. |
| 7 June 2016 | Amended | Grading process has been more specifically described and clarified. Certainty of evidence is used instead of quality. |
Contributions of authors
QD and GE co‐ordinated the contributions from the coauthors and wrote the final draft of the protocol. QD, SC, TC, and GE worked on the methods sections. QD and GE drafted the clinical sections of the background, and TC was the contract person with the editorial base. QD and GE wrote the protocol with assistance from AT, SC, RK, and TC. TC devised and carried out the search strategy. QD, GE, and SC wrote the statistical analysis and data synthesis sections. RK, SC, QD, GE, and AT contributed significantly to the protocol. RK was the team lead and co‐ordinator and a major contributor to the initial concept of the protocol. XS provided guidance for statistical analysis.
Sources of support
Internal sources
-
University of Alberta, Canada.
Salary support for: AT, TC, RK
External sources
-
Canadian Frailty Network, Canada.
Canadian Frailty Network Interdisciplinary Fellowship 2016 for: GE
-
Alberta Innovates Health Solutions, Canada.
AIHS Summer studentship for: QD
Declarations of interest
Gilgamesh Eamer: nothing to declare.
Amir Taheri: nothing to declare.
Sidian S Chen: nothing to declare.
Quinn Daviduck: nothing to declare.
Thane Chambers: nothing to declare.
Xinzhe Shi: nothing to declare
Rachel G Khadaroo: nothing to declare.
Notes
This protocol is based on standard text and guidance provided by the Cochrane Effective Practice and Organisation of Care (EPOC) Group.
New
References
Additional references
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