Transcript Perioperative Management of the Gertiatric Population

Nutritional Supplementation and Serum
Albumin Levels: Their Usefulness in Predicting
and Improving Operative Morbidity and
Mortality in the Geriatric Population
AMELIA CRAWFORD, PA-S2
OCTOBER 28,2011
Preoperative Testing
 Purpose is to identify underlying abnormalities or
assess the severity of a current condition that may
affect patient morbidity and mortality
 For the geriatric patient, the clinician must strike a
balance between routine testing and extensive
evaluation.
Preoperative Testing
 Best tools are history and physical exam:
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Patient’s overall health
Cognitive Functioning
Nutritional Status
Family & Social Support
Medication Review
Routine Tests
 CBC:
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Hemoglobin- minimum of 9-10 mg/dl.
WBC- identify any infections or underlying myeloproliferative
disorders
 Basic Metabolic Panel:
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Electrolytes: may be abnormal due to use of diuretics or ACEI/ARB
Creatinine Clearance- important for postop med dosing
Preop Serum Creatinine of >2.0mg/dl is a predictor of post op
cardiac complications in patients undergoing non-cardiac surgery
Albumin level- assess nutritional status
 Coagulation Studies:
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PT, PTT, INR
Routine Tests
 EKG:
 For males>40-45 YOA & females>55 YOA, patients with
systemic diseases like HTN, DM, PVD, hyperlipidemia,
cerebrovascular disease, those taking medications that
increase risk for cardiac toxicity
 Helps identify patients with previous infarcts, which increases
risk of complications
 Chest X-Ray:
 Patients >50 YOA & those cardiopulmonary or with preexisting pulmonary disease
 Risk of complications from anesthesia
Nutritional Assessment
 Geriatric population is at risk for deficiencies because
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appetite and calorie consumption often decrease
In those with nutritional deficiencies there is sometimes
concomitant depression, isolation, poor dentition, or
excessive alcohol consumption
BMI: <18.5 is cause for concern
Healing is delayed in the presence of even mild protein
calorie malnutrition.
Studies suggest that early recognition of protein
malnutrition and initiation of nutritional therapy can
shorten the length of hospital stays and improve patient
outcomes
Serum albumin & pre-albumin are often used as
nutritional status markers
Albumin
Complex, high molecular weight protein produced by
the liver
Widely used in nutritional assessment
Half-life of 18-20 days
 Normal value: 3.30 to 4.80 g/dL
 Affected by many factors including dehydration,
inflammation, hepatic and renal dysfunction
 The level typically takes 14 days to return to normal
when the pool has been depleted.
Pre-albumin
 A serum and cerebrospinal fluid carrier of the thyroid hormone thyroxine
(T4) and retinol, produced mainly by the liver.
 Lower levels correlates with protein malnutrition (within 1 week of change
in nutrient intake).
 Not affected by dehydration but systemic inflammation does cause a
decrease.
 Clinical studies indicate that determination of the pre-albumin level may
allow for earlier recognition of and intervention for malnutrition.
 Synthesis of pre-albumin increases above baseline levels within 48 hours of
protein supplementation in patients with protein calorie malnutrition and
returns to normal levels within eight days.
 ½ life of 2-3 days
 Normal level: 16-35 mg/dL
Preoperative Serum Albumin Level as a
Predictor of Operative Mortality and
Morbidity
GIBBS ET AL. ARCHSURG. 1999; 134; 36-42
Background Information
 Hypoalbuminemia has been shown to be associated
with increased mortality and morbidity rates in
hospitalized and community dwelling elderly
persons.
 Hypoalbuminemia has also been associated with
adverse outcomes after surgery.
Objective
 To improve precision and reliability of estimates of
the association between preoperative serum albumin
concentration and surgical outcomes
Design
 Prospective observational study
 Setting: 45 VA medical centers
 Patients: 54,215 major non-cardiac surgery cases
from the National VA Surgical Risk Study
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97.1% male
Mean age was 61 years
76% white, 18% black, 6% other ethnicities
General surgery (28.3%), Orthopedic (18.0%), Urology
(14.8%), Vascular (11.7%), Neurosurgery (8.4%), Thoracic
(7.3%), ENT (5.9%), Plastic (3.7%), Other (2.0%)
 Data collected until 30 days post-operatively
Design
 Independent Variables:
 1. Serum albumin values closest to the day of the surgery
(within 30 days)
 Dependent Variables:
 1. Operative Mortality: death due to any cause within 30 days
of the operation
 2. Operative Morbidity: 21 of the predefined complications
recorded within 30 days of the operation.
Primary Outcome
 30 day operative mortality and morbidity
Stastical Analysis
 Univariate Analyses- association between
preoperative serum albumin levels and mortality and
morbidity. Compared the predictive ability of albumin
level with that of each of 61 other preoperative variables.
 Multivariant Logistic Regression Analyses- assess
the predictive ability of albumin level independent of the
effects of other variables.
 Complication-Specific Analyses- association
between preoperative serum albumin and each of 21 predefined complications
Results
 Univariate Analysis:
 1. Albumin level was the best predictor of 30 day mortality and
morbidity.
 2. Albumin level alone correctly discriminated between
survivors and non-survivors 78% of the time
 For all operations, the mortality rate increases from less than
1% for albumin levels of 46g/L or higher to 28% for albumin
levels below 21g/L
Results
Results
 Multivariate Analyses:
 Albumin level is the strongest predictor in both mortality and
morbidity models for all operations and in several subspecialty
models
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Odds ratios for albumin level in all operations models indicate
that a decrease of 10g/L in albumin value was associated with
more than a 2 fold increase in the odds of dying and almost a 2
fold increase in the odds of a complication.
Results
 Complication-Specific Analysis:
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Albumin level was a relatively strong predictor of most of the
complications:
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particularly systemic sepsis, failure to wean off the ventilator, and
pneumonia
Results
Results
 Separate analyses were performed for a lower risk
segment of the sample and for women, and there was
a negative association between serum albumin level
and 30 day mortality for both groups.
Summary of Results
 A decrease in serum albumin from concentrations
greater than 46g/L to less than 21g/L was associated
with an increase in mortality rates from less than 1% to
29% and in morbidity rates from 10% to 65%.
 In regression models, albumin level was the strongest
predictor of mortality and morbidity as a whole and
within several subspecialties (independent of the effects
of other risk variables)
 Albumin level was a better predictor of some types of
morbidity, particularly sepsis and major infections.
Level of Evidence
Perioperative Oral Nutritional Supplements in
Normally or Mildly Undernourished Geriatric
Patients Submitted to Surgery for Hip Fracture:
A Randomized Clinical Trial
CARRETERO ET AL.
CLINICAL NUTRITION
OCTOBER 2010
VOL. 25; ISSUE 5: 574-579
Objectives
 To study whether perioperative administration of
oral nutritional supplements (ONS) are effective in
geriatric patients undergoing surgery for hip
fracture, starting at admission.
Design
 Randomized control trial
 Patients:
 60 patients total
 >65 YOA
 Admitted between May 2005 and September 2008 due to hip
fracture and underwent hip surgery
 No patients had been on ONS or received any other nutritional
support within the previous 6 months
 All patients had similar baseline characteristics
Exclusion Criteria
 1. Moderate to severe malnutrition:
 Weight loss of > 5% in the previous month or >10% in the
previous 6 months of their usual body weight
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ARF, CRF, Hepatic Insufficiency or Cirrhosis, Stage III or IV
HF, Repiratory Failure, GI conditions that precluded the use of
ONS
Interventions
 Control Group (n=30): no intervention
 Intervention Group (n= 30): Perioperative ONS initiated
at admission and maintained until discharge
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2 Fortimel 200mL bricks which provided 20g protein & 200 kcal
Amount of ONS and diet consumed by the patient was measured
after every meal.
 Blood testing and body measurements were done at
baseline, 48 hrs after surgery, then weekly, and also at
hospital discharge.
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Normal ranges:
Serum albumin = 3.3-5.2g/L
 Pre-albumin = 20-40mg/dL
 RBG are as follows= 3.0-6.0mg/dL
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Outcomes
 Primary:
 1. Change in albumin, pre-albumin, and retinol binding
globulin.
 2. Changes in weight, BMI, mid-brachial circumference, and
tricipital fold
 Secondary:
 1. Length of hospital stay
 2. Postoperative complications
Statistics
 Comparisons between both groups at baseline were
performed using the independent Student t test,
Mann-Whitney U test, or Chi-Square test
 General linear model was used for the comparison of
continuous variables throughout the study
 Backwards multiple logistic regression model was
employed to study the effects of multiple
independent variables on the occurrence of postoperative complications
Results
 Primary Outcomes:
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There was a significant change in albumin between the 2 groups
(F=22.536, P<0.001) from the time of admission until the time of
discharge, with the control group demonstrating a larger decrease in
serum albumin and worse post-op recovery compared to the ONS
group.
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Serum pre albumin also demonstrated similar significant changes
(F=6.654, P=0.001)
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RBG demonstrated a similar change, but this difference was not
significant (F= 2.281, p=0.089)
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No significant differences in the change in BMI (F=2.509, P=0.089),
tricipital fold (F=0.584, P=o.636), or the mid-brachial
circumference(F=0.031, P=0.864) between the groups.
Results
Open circles = control group
Filled circles= ONS group
Results
 Secondary Outcomes:
 Length of postoperative hospital stay was similar in the 2
groups (p= 0.664)
 No significant difference in postoperative complication rates
between the 2 groups (p= 0.091)
 Non-significant tendency for higher postoperative
complication rate in the control group, but no specific
complication could be identified as predominant in either
group.
Results
 Ancillary Analyses:
 Backwards multiple logistic regression analysis with the
occurrence of postoperative complication as the dependent
variable and age, gender, baseline BMI, mid-brachial
circumference & tricipital fold, non-protein, and supplemented
proteins per day as covariates.
The supplemented proteins per day was determined to be a
predictive variable ( OR= 0.925; 95% CI; P= 0.003)
 Suggests that higher protein intake is associated with a smaller
risk of postoperative complications
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Conclusions
 Perioperative administration of ONS is effective in
increasing serum proteins in nourished or mildly
nourished geriatric patients who undergo surgery for
hip fracture.
 Patients with higher protein intakes had fewer
postoperative complications
Level of Evidence
Final Comments
 Serum albumin and pre-albumin levels are used
frequently to monitor nutritional status.
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However, these markers are affected by more than just protein
nutrition.
Levels should be interpreted along with weight, BMI, physical exam,
and other labs.
 They are cost effective labs that can help predict the risk
of postoperative morbidity and mortality in geriatric
patients
 In geriatric patients undergoing surgery, correcting
nutritional deficits before and after surgery can help
prevent complications and improves mortality rates.
References
 Shenkin, Alan. Serum Prealbumin: Is It a Marker of Nutritional Status or of Risk of
Malnutrition? Clin. Chem., Dec 2006; 52: 2177 - 2179.

Beck FK, Rosenthal TC. Prealbumin: a marker for nutritional evaluation. Am Fam
Physician. Apr 2002; 15;65(8):1575-8.
 Woogler, JM. “Preoperative Testing and Medication Management.” Clinics in
Geriatric Management, Nov 2008; 24 (4): 573-583.
 Carretero et al. Perioperative oral nutritional supplements in normally or mildly
undernourished geriatric patients submitted to surgery for hip fracture: A
randomized clinical trial. Clinical Nutrition, Oct 2o1o;
29 (5):574-579
 Gibbs et al. Preoperative Serum Albumin Level as a Predictor of Operative Mortality
and Morbidity. Arch Surg. 1999;134:36-42