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Abstract

Background

Comprehensive Geriatric Assessment (CGA) is a validated multidomain assessment of an older person’s myriad issues that has shown positive medical outcomes in surgical settings. However, there is paucity of evidence in older Vascular inpatients.

Objectives

To determine if a Geriatric Liaison Service using CGA improves medical outcomes in older Vascular inpatients in Singapore.

Methods

This is a quality improvement prospective cross-sectional study. Vascular patients aged ≥65 years admitted between November 2018 to October 2019 were referred to the Vascular-Geriatric Service (VGS) at the surgeon’s discretion if they had acute medical issues, cognitive concerns, or functional decline. Patients admitted under Vascular Surgery during the preceding year but not referred to VGS were used as control. A pre- and post-analysis was conducted for outcomes of medical complications, while a multivariate analysis was done to look at LOS, 30-day unplanned medical readmissions and 30-day mortality rates.

Results

Patients had significantly lower rates of pneumonia (2.2% vs 10.8%, p = .021) and delirium (1.1% vs 18.3%, p < .001) post-VGS compared to pre-VGS. VGS decreased the odds of 30-day mortality by 79% as compared to the control group (OR = 0.21, 95% CI: 0.05-0.86, p = .030). The intervention group had increased risk of a longer hospital stay by 48% as compared to control (RR: 1.48 95% CI: 1.11 to 1.97, p = .008).

Conclusions

VGS was associated with reduction in some medical complications, and 30-day mortality in older frail Vascular inpatients with multimorbidity.

Keywords

Geriatric liaison service comprehensive geriatric assessment vascular surgery

Introduction

Rising numbers of older adults are undergoing surgical interventions, both elective and emergency.¹ This is partly due to demographic change - people living longer - and advances in medical technology and experience, allowing more older adults to become surgical candidates.^1,2

Older surgical patients face greater post-operative complications, a longer length of stay and increased mortality, compared to younger patients for the same surgical procedures.^1,3,4 Older patients referred to surgical teams present not only with the index pathology requiring surgery, but also pre-existing comorbidities. Multimorbidity, geriatric syndromes, age-related decrease in physiologic reserves, decreased nutritional status and frailty, are important interplaying risk factors that adversely impact postoperative outcomes.^5–7 Vascular patients in particular, are at higher risk of adverse outcomes, as they are often older and plagued with comorbidities such as hypertension, coronary heart disease, diabetes and peripheral vascular disease.⁷ It is known that pre-operative comorbidities is often associated with post-operative organ dysfunction.⁸

A Comprehensive Geriatric Assessment (CGA) is a multidisciplinary assessment of an older person’s medical, psychological, and functional capability, and includes development of a coordinated and integrated plan for treatment and follow-up.⁹ CGA has been well validated in community-dwelling and acute medical patients, with emerging literature of its utility in surgical inpatients as well.^{1,2,5,7,9–11} CGA improves outcomes in function, morbidity, and mortality, and reduces the likelihood of institutionalization in hospitalized older adults.^1,2,7,9,10 Positive outcomes such as fewer post-operative medical complications and a shorter length of stay (LOS) are also evident with the use of CGA in older surgical inpatients.¹²

Geriatric Medicine Liaison Services adopting the CGA model have shown promising outcomes in elective orthopedics, and both elective and emergency surgical settings, reporting lower incidence of post-operative medical complications, better pain control, earlier return of function, shorter LOS, and reduced mortality.^1,2,6,11 However, whilst there is much evidence for surgical patients, evidence for Geriatric Liaison Services using the CGA approach in older Vascular Surgery inpatients locally in particular are not as robust.¹³

Traditionally in our hospital, older Vascular patients are referred to the Geriatric team and seen on an as-needed consult basis, which leads to sporadic, inconsistent geriatric input, and inadequate follow-up on CGA interventions.

Aim

In this paper, we aim to determine if a Geriatric Liaison Service using the CGA approach can improve medical outcomes in older patients admitted under Vascular Surgery in a tertiary hospital.

Methods

Study design and population

This is a quality improvement prospective cross-sectional study done in a tertiary teaching hospital with a 1000-bed capacity. Patients aged 65 years and above admitted under Vascular Surgery between November 2018 to October 2019 were referred to the Vascular-Geriatric Service (VGS) at the surgeon’s discretion if they had acute medical issues, cognitive concerns, or functional decline. Patients admitted to the Intensive Care Unit were excluded.

The Singhealth Centralised Institutional Review Board granted exemption for this quality improvement initiative, and no patient consent was required.

VGS is a Geriatric Liaison Service comprising of a Geriatrician, a Geriatric Advanced Practitioner Nurse (APN), a Geriatric Pharmacist, a Vascular APN, and a Vascular Surgery junior doctor. VGS ward rounds were conducted twice weekly.

A CGA was done for all patients. The medical team assisted in proactive identification of risks and management of issues such as fluid overload, sepsis, delirium, and pain control. Medications were regularly reviewed by the VGS Pharmacist, with appropriate deprescribing and geriatric-centric optimization.

Nursing needs, including wound care and behavioral management of delirium and dementia, were attended to by the APNs.

Referral suggestions to appropriate Allied Health services were made, such as physiotherapists (PT) and occupational therapists (OT) for early mobilization and prevention of further functional decline. Speech therapist (ST) referrals were done for patients who have risks for swallowing issues. Patients at risk of malnutrition were referred to the dietician for nutritional optimization.

VGS also assisted in patient and family communication for patients with complex medical and discharge planning issues.

VGS followed the consultative model of care and implementation of the care suggestions was at the discretion of the primary Vascular Surgery team.

Outcome measures were medical complications, hospital length of stay (LOS), 30-day medical readmission rates and 30-day mortality rates.

Data sources and collection

Data on VGS patients was collected prospectively.

Outcomes of medical complications (myocardial infarction, fluid overload, atrial fibrillation, stroke, pneumonia, delirium) were hand collected by sieving through the case notes of the admission of interest.

Outcomes of hospital LOS, 30-day unplanned medical readmission rates and 30-day mortality rates, as well as anonymized control group data were derived from the Electronic Medical Records.

Statistical Analysis

Two types of analyses were done:

Pre- and post-analysis

75 consecutive patients were referred to VGS from November 2018 – October 2019, with a total of 93 visits, as some patients were admitted, and referred to VGS more than once.

A pre- and post-analysis was conducted to compare medical complications in these 93 visits before VGS was referred versus complications that occurred during the time VGS was on board (Figure 1).

Figure 1.

Pre- and post-analysis VGS cohort.

Multivariate analysis

A multivariate analysis was done comparing the unique persons seen by VGS from November 2018 – October 2019, to the unique persons admitted under Vascular Surgery in the preceding 1 year. The latest record was used if patients had multiple admissions to Vascular Surgery.

A total of 75 VGS unique patients and 293 controls were included in the analysis.

Data collected was expressed using frequencies, mean with standard deviation (SD) and median with interquartile range (IQR) for categorical, parametric and non-parametric variables respectively.

Among VGS patients, the McNemar test was performed to assess the difference in medical complications pre- and post-VGS whilst the Wilcoxon-Rank Test was performed on the hospital LOS and number of complications pre- and post-VGS.

The association between the baseline characteristics of the subject and intervention groups was assessed using χ² test or Fisher’s Exact test for categorical variables. Numerical variables were assessed using Independent t test if data was normally distributed or Mann-Whitney U-test if data was not normally distributed.

Univariate and multivariate analyses were performed using Logistics Regression for binary outcomes which were coded as “Yes” or “No” such as unplanned medical readmissions and 30-day mortality. Poison Regression was performed for count outcomes such as the total LOS in hospital. However, the deviance for total LOS was greater than one which indicated that data were over-dispersed, hence Poisson regression with negative binomial distribution was performed to account for this issue. Cox regression was performed to assess the progression of 30 days readmission after discharge between intervention and control groups.

Potential confounders such as age, medical comorbidities (atrial fibrillation, chronic kidney disease, chronic obstructive pulmonary disease, asthma, diabetes, ischemic heart disease, peripheral vascular disease, cognitive impairment, hypertension, pneumonia, stroke), and selected procedures (amputation, angiography, angioplasty, bypass, debridement, embolectomy, thrombectomy, embolization, thrombolysis) were adjusted for in the multivariate analysis. Patients who had missing data on comorbidities were assumed as not having the condition.

All statistical analyses were performed using IBM SPSS ver 20.0. Armonk, NY: IBM and statistical significance was set at p < .05.

Results

75 unique patients were referred to VGS during these 12 months, with a total of 93 visits. Patients admitted under Vascular Surgery during the preceding year but not referred to VGS were used as the control group (n = 293).

Outcomes of medical complications

Compared to control, the VGS cohort (n = 93) had significantly higher comorbidity burden, including IHD (45.2% vs 13.3%, p < .001), stroke (23.7% vs 4.8%, p < .001), and cognitive impairment (31.2% vs 2.7%, p < .001) (Table 1).

Table 1.

Demographics of control vs VGS.

	Control (n = 293)	VGS (n = 93)	p value
Age, mean (SD)	76.7 ± 79	79.6 ± 82	.006
Comorbidities (%)
AF	29 (9.9)	15 (16.1)	<.001
AMI	22 (7.5)	16 (17.2)	.023
CCF	15 (5.1)	9 (9.7)	.015
CKD	114 (38.9)	39 (41.9)	.028
DM	200 (68.3)	72 (774)	.128
IHD	39. (13.3)	42 (45.2)	<.001
PVD	146 (49.8)	60 (64.5)	.027
Cognitive Impairment	8 (27)	29 (312)	<.001
HTN	207 (70.7)	77 (82.8)	.003
Stroke	14 (4.8)	22 (23.7)	<.001
COPD/Asthma	4 (1.4)	8 (8.6)	.002
Charlson Comorbidity Index (CCI) Scores
Min–max	0–9	4–11	<.001
Mean (SD)	3.24 ± 1.9	7.49 ± 1.8	<.001
Clinical Frailty Scale (CFS) Scores
Mean	NA	5.6	NA
CFS 1-4 (%)		17 (18.3)
CFS 5-6 (%)		58 (62.4)
CFS 7-8 (%)		18 (19.4)
Surgical Interventions (%)
Amputation (Major/Minor)	68 (23.2)	36 (38.7)	.007
Angioplasty +/− Bypass	143 (48.8)	54 (58.1)	.172
Wound debridement	116 (39.6)	48 (51.6)	.059

The mean CCI score for VGS was 7.49, which predicts a 0% 10-year survival rate, as compared to a score of 3.24 for the control group.

81.8% of the VGS cohort was frail by CFS criteria. No CFS data was available for the control group.

Both groups were old, with a mean age of 77–80 years.

Compared to the control group, the VGS cohort underwent more major and minor amputations (38.7% vs 23.2%, p = .007).

Pre- and post-analyses were conducted to compare medical complications in the same patients before VGS was involved (pre-VGS) versus complications that occurred during the time VGS was on board (post-VGS) (Table 2).

Table 2.

Comparison of medical complications between the pre- and post-VGS groups.

Medical Complications (%)	Pre-VGS (n = 93)	Post-VGS (n = 93)	p value
Myocardial infarction	9 (9.7)	3 (3.2)	.070
Fluid overload	14 (15.1)	8 (8.6)	.146
Atrial fibrillation	2 (2.2)	0 (0.0)	NA
Pneumonia	10 (10.8)	2 (2.2)	.021
Delirium	17 (18.3)	1 (1.1)	<.001

The mean length of time from admission to VGS referral was 11.1 days.

In terms of medical outcomes, patients had significantly lower rates of pneumonia (2.2% vs 10.8%, p = .021) and delirium (1.1% vs 18.3%, p < .001) post-VGS compared to pre-VGS. There was a trend towards lower rates of myocardial infarction (3.2% vs 9.7%, p = .07) and fluid overload (8.6% vs 15.1%, p = .146) post-VGS.

These positive medical outcomes were achieved despite reduction of referrals to other medical subspecialties by 52% (IRR = 2.1, 95% CI: 1.4 to 3.2, p = .001) in the VGS group.

Outcomes of 30-day mortality, unplanned 30-day medical readmissions, and LOS

A multivariate analysis was done comparing the unique persons seen by VGS in 1 year to the unique persons admitted under Vascular Surgery in the preceding 1 year (Table 3).

Table 3.

Outcomes for VGS (unique persons) vs control.

Outcomes (n = 463)	Unadjusted (95% CI)	p value	Adjusted (95% CI)	p value
Hospital length of stay	RR: 2.51 (1.95, 3.23)	<.001	RR: 1.48 (1.11, 197)	.008
30-day medical readmissions	OR: 1.42 (0.69, 2.90)	.341	OR: 1.24 (0.51, 3.00)	.632
30-day imortality	OR: 1.24 (0.55, 2.80)	.600	OR: 021 (0.05, 0.86)	.030

Results showed that enrollment into the VGS service decreased the odds of 30-day mortality by 79% as compared to the control group (OR = 0.21, 95% CI: 0.05–0.86, p = .030). The intervention group was more likely to have medical readmissions within 30 days, but this was not statistically significant (OR = 1.2, 95% CI: 0.5 to 3.0, p = .632). The intervention group had increased risk of a longer hospital stay by 48% as compared to control (RR: 1.48 95% CI: 1.11 to 1.97, p = .008).

In terms of discharge destination, more patients were identified as requiring rehabilitation and were sent to community hospitals and stepdown care in the VGS group than control (22.6% vs 7.1%). The takeover rate to the geriatric wards was reduced by 18.4% (30.1% vs 48.5%, p = .02) in the VGS group, which meant that fewer patients underwent unnecessary transfers.

Discussion

Older Vascular inpatients benefit from a Geriatric Liaison Service comprising of a Comprehensive Geriatric Assessment. The VGS cohort were frail, had significantly more comorbidities, and underwent more surgical interventions. The service was associated with a reduction in the incidence of pneumonia and delirium as well as 30-day mortality in these patients. VGS patients, however, have an increased risk of a longer hospital stay.

Older surgical patients have a higher incidence of nosocomial pneumonia compared to younger patients. Significant risks are poor nutrition, aspiration, depressed level of alertness and antacid use.¹⁴ Increasing age, severity of illness and longer LOS prior to the diagnosis are associated with worse prognosis for surgical patients with pneumonia.¹⁵

By using CGA methodology for older elective surgical patients, the Proactive Care of Older People Undergoing Surgery (“POPS”) care model also showed improvement in post-op medical complications including pneumonia (20% vs 4%, p = .008) and delirium (19% vs 6%, p = .036) in their pre- and post-intervention evaluation.⁶

Under VGS, patients at risk for swallowing issues were proactively referred to a speech therapist and given appropriate diet and fluid consistency thereby reducing the risk of aspiration pneumonia. There was also constant reinforcement of early mobilization and regular sitting out of bed to reduce atelectasis. These interventions may have contributed to the decrease in the rates of pneumonia for the post-VGS group.

Thirty two percent of the VGS cohort were cognitively impaired, suggesting a higher risk for delirium, and hence a need for proactive delirium prevention measures. A study by Inouye et al. showed that multicomponent non-pharmacologic interventions targeting risk factors for delirium can lower its incidence significantly compared to usual care.¹⁶ Non-pharmacologic measures utilized by VGS included regular review of medications, bowels and nutrition, proactive optimization of pain control, frequent re-orientation, and early mobilization.

One of the main challenges in the implementation of these measures is that the patients were in non-Geriatric acute wards and staff were not specifically trained in geriatric care. The VGS team also only rounded twice a week, hence interventions that were planned may not have been optimally followed up. Despite these challenges, VGS was able to significantly lower the incidence of delirium (1.1% vs 18.3%, p < .001).

Almost half of the VGS patients have IHD and/or CKD which are associated with increased risks for cardiac events and fluid overload. Patients undergoing angioplasty are routinely given IV hydration to reduce their contrast-induced nephropathy risk, but this also increases risk of fluid overload if not done judiciously.

In another study of geriatric surgical patients, 21% developed one or more postoperative adverse events with reduced functional status and signs of fluid overload as the main predictors detected preoperatively.¹⁷

Under VGS, there was a trend towards lower myocardial infarction rates and fluid overload rates. This was achieved by proactive monitoring and guidance of the fluid balance.

In contrast to other studies, VGS patients were more likely to have a longer hospital stay than control. Use of CGA in elective surgical patients have shown reduction in the LOS by 2.21 to 4.5 days^6,18 Partridge et al identified the following potential factors that contributed to LOS reduction in their RCT study: fuller preoperative assessment and optimized medical morbidity, early identification and management of potential social issues at discharge and standardized management of postoperative complications.¹⁸ In a Cochrane review on the use of CGA in the elderly, the LOS was highly heterogeneous with three of the five studies reporting reduced LOS and one found an increase in LOS attributed to lower transfer rate to rehabilitation hospitals.²² On the other hand, Leung et al reported that post-operative adverse outcomes led to longer median hospital stay compared to those who did not develop complications.¹⁷

Interestingly, VGS has reduced medical complications and mortality despite fewer referrals to other medical sub-specialties. The prolonged LOS may be attributed to by long referral times to the VGS service (∼11.1 days), more right-siting to community hospital/stepdown care which means patients have to wait for bed availability, and lower takeover of care to Geriatric wards (hence, longer LOS attributed to the Vascular admission). The VGS rounds are done only twice a week which means that care coordination was mostly done by the primary team less familiar in discharge planning.

Limitations of the study

VGS was a CGA-based inpatient geriatric consultation service. The timing of referral and final decision on patient’s care plans were at the discretion of the primary Vascular Surgery team. Patients were referred and reviewed during the scheduled VGS reviews, hence, CGA was not always done preoperatively. The implementation of the CGA interventions was challenging since VGS was not able to reinforce these in between the twice-weekly rounds. There were no multidisciplinary meetings, hence discharge planning and care coordination were not consistently carried out in a timely manner. The service and care delivery may be improved with improvement in the care coordination by having a dedicated coordinator and holding regular multidisciplinary meetings to discuss on the rehabilitation goals and care plans.

Increasing age is an important risk factor for both morbidity and mortality for elderly patients undergoing major surgery.¹⁹ Age-related physiologic decline leads to frailty which is associated with adverse outcomes like falls, delirium and disability.²⁰ In addition, aging is also associated with multimorbidity which further depletes the elderly’s functional reserve.²¹ Frailty is associated with higher mortality across all noncardiac surgeries with a mortality of 43% for those deemed very frail.²² Among elderly patients undergoing major operations, those who are aged 80 years and above had a morbidity of 51% and mortality of 7%.¹⁹

These findings highlight the need for a more comprehensive risk assessment for the elderly than the preoperative tools used in the younger patients. Low-to moderate-stress procedures may become high-risk for frail patients; hence, frailty screening should be incorporated in the preoperative assessment.²²

This is an area of improvement for subsequent review of the VGS service to review patients’ frailty status and association with outcomes as well as changes in frailty status post VGS intervention.

Functional outcomes were not analysed and this could have given additional information on the impact of early mobilization and rehabilitation. Patient outcomes with regards to enhanced nutrition were not collected. Moreover, improvement in adverse drug outcomes with proactive medication review and reconciliation was not reviewed. In analysing the medical outcomes, a matched case control or a randomized control trial would have been better than the pre- and post-analysis of the same VGS patients.

Conclusions

VGS is the first formal Geriatric Liaison Service for surgical patients in our hospital. The VGS cohort were mostly frail with more comorbidities and significant cardiovascular issues and had undergone more surgical interventions than the control group. Using CGA, VGS was able to reduce pneumonia, delirium, and mortality rates despite the increased risk of perioperative complications that is associated with the risk factors present in the VGS cohort. Considering the gaps identified in the current structure, next plans include building surgical staff capabilities in geriatric care, incorporating multidisciplinary meetings, instituting daily reviews, and facilitating care coordination to improve patient care and outcomes.

Ethical statement

Ethical approval

Ethical approval for this study was waived by the Singhealth Centralised Institutional Review Board (CRIB 2020/2276).

Footnotes

Acknowledgements

We would like to thank APNs Wang Chun Mei and Cheng Shu Hua,Ms Tan Pei Ting,Dr Ivan Ngeow,and Dr Lew Pei Shi for their assistance in this study.

Author contributions

CSMC,HL and FL conceived the study and were involved in protocol development and data analysis. SKV,CSMC and HL co-wrote the first draft of the manuscript. All authors reviewed and edited the manuscript and approved the final version.

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research,authorship,and/or publication of this article.

Funding

The author(s) received no financial support for the research,authorship,and/or publication of this article.

ORCID iD

Christine Shi Min Chau

Data Availability Statement

The

generated and/or analysed in this study are available from CSMC (corresponding author).

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