CHAPTER 5

PRE OPERAU\,IE, ME,D ICAL ASSE SSMENT

Lopa Dalmia, DPM

INTRODUCTION

In the United States, more than 33 million surgeriesare performed annually and each year approximately1 million patients sustain medical complications aftersurEaery. Complications inciude myocarclial infraction,hean failure, stroke, pneumonia, respiratory failure,venor-rs thromboembolism, delirium, or renal failure.'Preoperative medical assessment is an impofiantcomponent of surgical planning. The podiatricsurgeon, hospitalist, and anesthesiologist are keyplayers in determining intra-operative risks and riskof postoperative complications for each patient priorto surgery. A thorough preoperative medical assess-

ment can decrease the length of a hospital stay as

well as minimize postponed or cancelled surgeries.'Preoperative medical assessment involves a

history and physical examination, focusing onrisk factors for cardiac, pulmonary and infectiouscomplications, and a determination of a patient'sfunctional capacity. Specific components of thepreoperatiye evaluation will be outlined, guidelineswill be offered for preoperative risk assessmentfor medical comorbidities inr.olving cardiac compli-cations, pulmonary complications, diabetes mel1itus,

and nutrition.

PTrySIOLOGIC EFFECT OF SURGERY

The initial hours following sr-rrgical or traumaticinjury are metabolically associated with a reducedtotal body energy expenditure and urinary nitrogenwasting. Upon adequxte resuscitation and stablliza-tion of the injured patient, a reprioritizatron ofsubstrate utilization enslles to presefl/e vital organfunction and for the repair of injured tissue. Thisphase of recovery also is characterized by functionsthat all pafiicipate in the restoration of homeostasis,such as augmented metabolic rates and oxygenconsumption, enzymatic preference for readilyoxidizable substrates such as glucose, and stimula-tion of the immune system.

Epinephrine, norepinephrine, and cortisollevels increase during surgery and remain elevatedfor 1,-3 days.' Serum antidiuretic hormone leve1s

may be elevated for up to 1 week postoperatively.There is evidence that anesthesia and surgery maybe associated with a relative hypercoagulable andinflammatory state mediated 1ry increases inplasminogen activator-1, factor MII, and plateletreactivity, and increased levels of tumor necrosisfactor, interleukins 1 and 6, and C-reactive protein.r

Anesthetic agents r-rsually callse peripheralvasodilatation, and most of the commonly usedgeneral anesthetic regimens also decrease myocar-dial contractility. These effects often result intransient mild hypotension or, less fiequently,prolonged or more severe hypotension. A decreasein tidal volume caused by general and spinal-epidural anesthesia can close smal1 aitways and leacl

to atelectasis. These effects may be less evident withspinal or epidural anesthesia compared with generalanesthesia. The degree to which these hyper-coagulable or inflammatory states contribute toperioperative rnorbidity is not known.

Perioperative morbidity and mortality generallyfal1 into one of three categories: cardiac, respiratoryand infectious complications.'r One large studydocumented at least one complication in 17 percentof sr-rrgical patients (Table 1).'

Thble I

SURGICAI, COMPLICATIONS'

ComplicationInfection'JToundPneumoniaUrinary tractSystemic sepsisRespiratoryPneumoniaFailure to w'ean from

respirator in 48 hoursUnplanned intubationPulmonary embolusCardiacPulmonary edemaCardiac affestMyocarclial infarction

Incidence o/o

14.3

5.7

3.63.52.7o5.l.o

4)2,40345)17.5

0.7

24 CHAPTER 5

PREOPERATTVE HISTORYAND PTrySICAL EXAMINATION

Preoperative assessment is typically performed daysbefbre surgery. It entails a thorough review of thepatient's history, drug history, surgical and:rnesthetichistory, alcohol and tobacco use, allergies to drugsand latex, bleeding history, functional class, andphysical examination.

HistoryThe history includes information about the conditionfbr which the surgery ls planned, any past surgicalprocedures, the patient's experience with anesthesia,and chronic medical conditions, particularly of theheart and lungs. In children, the history includesbimh history, focusing on risk factors such asprematurity at bifih, perinatal complications, andcongenital chromosomal or anatomic malformations,and history of recent infections, particularly upperrespiratory infections or pnetrmonia.

MedicationsMedications with dosages, including oyer-the-counter medications and herbal medicines arenoted. Drug dosages may need to be adjusted in theperioperative period. See Table 2 for preoperariverecommendations of cardiovascular, pulmonary,diabetes, and other meclications. Immunizationstatus can be documented, and vaccines can beupdated if ner'essary.

AllergiesLatex allergy is uncommon and occurs in 5-10% ofthe population.r Patients with a history of chronicurologic problems, spina bifida, and atopicdermatitis are considered high risk for latex allergy.Nlergy to antibiotics, pain medications, metal andadhesive tapes are common.

Social HistorySmoking history and alcohol and drug use areimportant to reduce perioperative pulmonarycomplications.s Moller et al recorded smoking anddrinking habits, and history of chronic diseasesof 811 patients who had undergone hip or kneearthroplasty. They found that smoking was thesingle most impofiant risk factor for the develop-ment of postoperative complications, pafiicularlythose relating to wound healing, cardiopr-rlmonary

complications, and the requirement of postoperativeintensive care, A delay in discharge from the hospi-tal was usual for those experiencing a complication.In those patients requiring prolonged hospitalization(>15 days) the proportion of smokers with wor:ndcomplications was twice that of non-smokers.i

Smoking has known cletrimentai effects onhealing bone and tissue. It has been associated withinteruertebral disc disease and low back pain.Further, nicotine causes delay in tendon-to-bonehealing in animal mode1s.6 The patient should quitsmoking B or more weeks before surgery/ tominimize the surgical risk associated with smoking.'

Functional Capacity and Exercise ToleranceThe Duke Activity Status Index (DASI) is a briefself'-administered questionnaires cleveloped in 1989to determine the degree of physiologic stress thepatient can handle.n The index inch:des commonphysical activities ranging from running to beingbedbound anci places into 1 to 4 functional classesbased on the single most difficult activity that thepatient can perform. A metabolic equivalentof activity (MET) is listed for each functionalclassification. One MET is equal to 3.5 rnl ofoxlrgen usecl per kilogram per minute of activity.If a patient can run and swim, then he has MET of>B and is considered in ftrnctional ciass I of DASI.If the patient can climb stairs, do yard work andwalk uphi11 then he has MET of 4-5 and isconsidered in functional class II of DASI.T If thepatient can do light house work and walk, then hehas MET of <4 and is considered in functional classIII of DASI, and if the patient is bedbound or hasIimited activities of daily iiving then the patientis classified in Class IV of DASI. The risk ofperioperative cardiovascular complications is 1owfor patients reporting that they can tolerate morethan 4 MET.9

The ACC/AHA Task force defines functionalcapacity as poor- or moderate-based patientactivity level and metabolic equivalents. Patientswho are able to perform light house work andwalk 1-2 blocks on leve1 ground exhibit poorfunctional capacity with METs of 7-4. Patients whoare able to climb stairs and hil1s, run shortdistances, bowl, dance, golf, and swim havemoderate functional capacity with METS >4.'0

The validity of self repofiecl exercise tolerance inpredicting perioperative risk has been controversial.Howeveq Reilly et ai performed a study of 600

CHAPTER 5 25

Table 2

RECOMMENDATIONS

DRUG/DRUG CATEGORY

Aceta hen

Aspirin

NSAID

Clopidogrel

CardiovascularDigioxinClonidine

Beta-blockers

Ca channel blockersDiuretics,qcn inhibitors

BASED ON HISTORY AND PITYSICAL EXAMINATIONS'

RECOMMENDATIONSCONTINUE use

HOLD 7-10 days prior to surgery- due to irreversible inhibitor activi

HOLD 3 days prior to surgery- due to reversible inhibitor activ

HOLD 7-10 days prior to surgery-due to its irrer ersihle antiplatelet effect

CONTINUE up to and including clay of sLlrgery

lateiet rlo-ox

telet

iotensin II rece or blocker ofCholesterol loweri drucs

Inhalecl beta-agoinist

I4b419d ipratropiumInhaled corticosteroidDiabetes DInsulin

Metformin

Sulfonylureas

ThiazolidinedionesAloha-slucosidase inibitors

VitaminsVitamin E supplements

patient undergoing 6L2 non-cardiac procedures toshow that patients reporting poor exercisetolerance had more perioperative cardiopulmonarycomplications than the patients with good exercisetolerance w-ho may better tolerate the physicalrigors of surgery and mobilize more rapidly posroperatively.e

ion during su

HOLD 1 da rior to su

CONTINUE up to and inclr-rding day of surgery

Give long-acting insulin al l/t the normal dose, hold short-actingmorning of su

HOLD 2 days prior-due to risk of lactic

HOLD on the morning of surgery

HOLD 7-10 days prior to surgery- due to a risk of bleecling

surEaeryCHF because there is an increased risk

to sllrge4/acidosis if has renal roblems rativel

Laboratory Testing

Preoperative laboratory testing should be selective

and not routine. Current recommendations are

for laboratory tests basecl on the specific signs,

symptoms and diagnosis." Normzrl lab test results

obtained 4 to 5 months before surgery may be used

as preoperative tests, provided there are no changes

in the clinical status of the patient. MacPherson et al

HOLD on-especially

the morning ofif indication is

Pu

26 CHAPTER 5

found that <20/o of test results conducted 4 monthsbefore sur5lery had changed at the rime of clinicalevaluation. Preoperative laboratory studies include acomplete blood count, extensive blood chemistryprofile, coagulation profile, urinalysis, electrocardio-gram (ECG), and chest radiographs.

A urine pregnancy test should be consideredfor women of childbearing age. Chemlstry profileshould be perfbrmed in patienrs wirh a history ofhypefiension, diuretic use, COPD or obstructivesleep apnea, diabetes, renal disease, chemotherapy.Complete blood count shor-rld be performed inpatients with a history of fatigue, dyspnea onexertion, liver disease, blood loss, signs ofcoagulopathy, or tachycardia. Coagulation profile isindicated if the patient is receiving anricoagulanttherapy, has a family or personal history thatsuggests a bleeding disorder or has evidence of liverdisease." Renal and liver function tests areindicated for patients who have a medical conditionor medication use that would selve as indications forthese tests. An ECG is not routinely indicated inpatients 40 years or youngeq but it shoulcl beobtained in patients older than 40 years or inpatients with cardiac indications based on the pastmedical history."

Chest radiographs should be obtained if thereare signs of pulmonary disease.

PREOPERATTYEANESTHESIA ASSESSMENT

Modern anesthesia is extremely safe. Mortalityamong healthy patients undergoing surgery is 1ow;estimates range from 0.01 to 0.03o/o.3 patient andprocedure related factors are more importentcontributors to perioperative morbidity thananesthesia itself. Inhalational anesthetic agentshave predictable physiologic effects. All inhala-tional anesthetic agents are lnyocardial depressants.Although not clinically significant in healthypatients, this effect leads to a dependence oncardiac preload that may cause an accentuatedresponse to the induction of anesthesia in patientswho are volume-depleted due to illness or overdiuresis or who have left ventricular dysfunction.Anesthesia leads to a decrease in lung volumes,which may lead to atelectasis and is a principalfactor leading to the development of postoperativepulmonary complications.

Controversy exists regarding the relative safety

of general versus spinal or epidural anesthesia inpatients at risk for postoperative cardiac orpulmonary complications. In a recent large meta-analysis of randomized controlled trials ofanesthetic technique, patients who were random-ized to spinal or epidural anesthesia as acomponent of their anesthesia had significantlylower rates of venous thromboembolism,pneumonia, respiratory depression, myocardialinfarction, or death than patients receiving generalanesthesia exclusively; relative risk reductionsranged from 30 to 550/0. In general, the choiceof anesthetic technique or agent, the decision touse invasive hemodynamic monitoring, and theregulation of body temperature should be left tothe anesthesiologist.

The American Society of Anesthesiologists(ASA) has adopted basic srandards for theevaluation of patients prior to surgery. Thesestandards require the anesthesiologist to determinethe medical status of the patienr by developing aplan of anesthetic care and to discuss this plan withthe patient. Table 3 discusses the American Societyof Anesthesiology ASA classification along withexamples of each class. Although subjective, ascore of 2-5 indicates an increased level of severityand increased postoperative morbic1ity.,,

PREOPERATTVECADIOVASCIIIAR ASSESSMENT

Cardiovascr-rlar disease is the leading cause ofdeath in United States, with more than 60% ofcardiovascular-related deaths due to coronary afierydisease.'3 Ofihopedic or podiatric surgery is oftenconsidered to pose an intermediate to low risk forcardiac complications owing to shofi anesthesia andoperating time.'o Howeveq many podiatric patientshave multiple coronary risk factors, includingsmoking, diabetes, hypefiension, elevated choles-terol, and obesity.'a Risk of postoperative cardiacdeath or major cardiac complications is less than 6o/o

in patients older than,{0 years undergoing major non-cardiac operations. Howeveq the risk is not uniform,and is increased by old age and pre-existing heartdisease. The most impofiant element of cardiac riskevaluation is based on cardiovascular history,physical examination and electrocardiography.

Several multivariate indices of risk have beendeveloped for patients with known or suspectedcardiac disease. Al1 seem to be similar in their

CHAPTER 5 27

Thble 3

PREOPERATTVEAIIESTHESIA ASSESSMENT:

American Society of Anesthesiology

Class III

(ASA) classification"

A normal, healthy patientEx: healthy with good exerciseloleranceA patient with mild systemic diseaseEx: Controlled hypertension orcontrolled diabetes without systemiceffects, cigarette smoking withoutCOPD, anemia, mild obesity, ageyounger than 1 year or older than 70yeafsl pregnancy

A patient with severe systemic diseaseEx: controlled congestive heafi failure(CHF), stable angina, old myocardialinfarction, poorly controlled hyperten-sion, morbid obesity, bronchospasticdisease w-ith intermittent symptoms,chronic renal failure.

A patient with severe systemic diseasethat is a constant threat to life.Ex: unstable angina, symptomatic COPD,symptomatic CHF, hepatorenal failure

A patient with a critical medical condi-tion with little chance of survival with orwithout the surgical procedure.Ex: multiorpaan f'ailure, sepsis syndromewith hemodynamic instability, hypother-mia, poorly controlled coagulopathy

A declared brain dead patient who is

undergorng anesthesia care for thepurposes of organ donation

If the proceclure is an emergency, thephysical statlrs is followed by "E" (forexample, "2E")

Table 4

AMERICAN COLLEGE OFPHYSICIANS (ACP) GUIDELINES

RiskAge older than 70 years 5

Myocardial infarction within six months 10

Myocardial infarction after six months 5

Canadian Cardiovascular SocietY

Angina Classification*

Class I

Class II

Class fV

Class V

Class \lI

E

Class IIIClass IV

Unstable angina within stx months

Alveolar pulmonary edemzt

Within one weekEver

Suspected critical aofiic stenosis

ArhythmiaRhyhm other than sinus or sinus plus

atrial premature beats 5

More than five premature

10

20

10

10

5

20

5

10

5

ventricular beats

Emergency operation

Poor general medical status

Class

IIIIII

Points0to1520 to 30

37+

Cardiac riskLow

High

ability to predict cardiac problems during the

operation. The American College of Physicians(ACP) Guideline is purely-evidence based. TheACP guideline includes Detsky's modified cardiacrisk and a list of low variables. In 1986, Detskyproposed a modified Goldman's cardiac riskassessment by calculating the overall complicationrate stratified by type of surgical procedure (Table

4). Goldman's cardiac risk index in 7977 was one

of the first attempts to systematically evaluate a

patient's rlsk of cardiac complications with surElery.

This index cornpiled the risk factors into a pointscale that correlated with a patient's risk forperioperative cardiac morbidity and mofiality.'5

Patients at high risk for complications usuallywarrant cardiology consultation and possiblyangiography. Cardiac stress testing should be

performed in patients at intermediate risk ancl withpoor functional capacity or who are undergoinghigh-risk procedures, such as vascular surgery. For

patients with minor clinical predictors, only patients

w-ho have poor functional capacity and are under-going a high-risk procedure requires stress testing.

Patients with positive stress test resultswarrant cardiology consultation before proceedingwith surgery.

28 CHAPTER 5

The American College of Cardiology and theAmerican Heart Association (ACC/AHA) guidelinesuses the best evidence available. It was developedin 1,996 based on J main considerations inassessing cardiac risk: the patient's clinicalpredictors, the patient's functional capacity, and theindividual risks of specific types of surgery. Figure1 outlines the step wise approach. The clinicalpredictors are classified as major, intermediate orlow (Table 5). Patient's functional capacity is basedon exercise capacity as discussed earlier. Most non-cardiac surgeries, including orthopedic andpodiatric surgeries have intermediate or minor riskpredictors. Non invasive testing is indicated in thepresence of 2 of the J negative factors: intermediateor major clinical predictors, high risk surgery andpoor exercise capacity.

The Revised Cardiac Risk Index clescribed byLee in 7999 and customized by Kerrai in 2005 is

Thble 5

ACC/AHA CLINICAL PREDICTORSOF INCREASED PERIOPERATTVE

CARDIOVASCUU.R RISK(MYOCARDIAL INIFARCTION,

HEART FAILURE, DEATH)

MaiorUnstable coronary syndromesDecompensated heart failureSignificant arrhythmiasSevere valvular disease

IntermediateN{i1d angina pectorisPrevious MI by history or pathologic Q wavesCompensated or prior heart failureDiabetes mellitus (particularly insulin-

dependent)Renal insufficiencv

MinorAdvanced ageAbnormal ECGRhythm other than sinusLow functional capacityHistory of strokeUncontrolled systemic hypertension

based on 6 independent predictors of major cardiaccomplications. The six predictors are: high-risksurgery, preoperative treatment with insuiin, pre-operative serum creatinine level Elreater than2mg/dL, history of ischemia heart disease,history of congestive heart failure, and history ofcerebrovascular clisease.

If the patient has no clinical predictorsmentioned above, the associated risk of cardiaccomplication is 0.4-0,5%t. The presence of 1

ciinical predictor increases the risk of cardiaccomplication to 0.9-7.3o/o. If the patient has 2

clinical predictors mentioned above, the associatedrisk of cardiac complication is 1-7o/o a.nd 3 or moreclinical predictors increases the risk of cardiaccomplications to 9-710/0. This system stratifies the riskof cardiac events, however does not make anyspecific recommendations as to what to do withthe information

In summary) recommendations do not call forpreoperative cardiac testing in all patients. Theneed for further cardiac evaluation before surgeryis cletermined by the clinical risk predictorsidentified from the patient's history, physical exam-ination, ECG and fr-rnctional status, along with therisk associated with the operation itself. Carcliacinterwentions are recommended only for patientswho would benefit regardless of any planned non-cardiac surgery.'n

It should also be emphasized that almost half ofperioperative cardiac complications are due to post-operative ischemia or congestive hearl failure.'r Theincidence of postoperative complications is the high-est in the first 48 hours after surgery, and ischemia isclinically silent in up to 90 percent of cases.'3 Whilepreoperative risk assessment and interuentions areimpofiant, attention to possible complications in thepostoperative period is also crucial.

PREOPERATTVEPULMONARY ASSESSMENT

Estimation of cardiac risk is a major focus of the pre-operative evaluation; postoperative pulmonarycomplications are as prevalent as cardiac complica-tions and contribute equally to morbidity, mortality,and length of hospital stay. Therefore, estimation ofthe risk of puhnonary complications is a necessarypart of the preoperative evaluation. Impofiant post-operative pulmonary complications include

CHAPTER 5 29

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t ::, I 1,"ar"aiffiifr*"r;r.sr6e& s&{r& a

*&6' t']o

*3/'^--*:.tb,r Jl

tri*re&& reli {t{tr&&*6 li rri@ex

,*t s t,rted ttedi.lar*"

' ur3,el3x r*,&1&ry

" 3e*{n8&rx&1et*r{f

sri?1t*r"rss

" $eqltg !{,trr&t

&& *,,&*rdtr!r{tr!,*r trli*r$r*{tst& c,lnte&frsdiet&rst

' L{,d ae*tr}e t $sev!9. fr;}r

'ra" e{xi$*ri*.etete:,r,i*r Si"tf

' frrabals$ r$e{l&Jc

. P€{al teutlicigMF

flrexr.tiirrad,

$t,{qltllt ti,'

&rgP *1 uo*Laralrtr* t*3!1r]!,

lrv*}i"e l&eliet}

S{ep* {stlicrr,r*iriclsr$ ,r,ae Ct{r}tre,l Pta*i*lss *

,}d!r'rxx{, t S&

" At"l${.&S €C*.8hy1t'f''elh*t

. tr? &$rdt**r,

. |nelorslrsts' t r6*?dt6d $tst*n f

hyt*{t*x{t&.l

f r*e*&a, eteiy

$tt ltc&l rl*t

plgpy r*r*t*v{$tr{lretlrt

tn"9$i"r l&&tin&

Figure 1; ACC/AHA Algorithm

,n{erea{rie1a €,iff ,f.tt f tsdi{!etEt

$rlrri,qs*&{ &{rr&'rrtsr;rlnd br tle6tn!,e*&{t !r&&ta&nl rtt*rt*

Figure I

30 CHAPTER 5

pneumonia, respiratory failure with prolongedmechanical ventilation, atelectasis, bronchospasm,and exacerbation of underlying chronic obstructivepulmonary disease.'6 A careful history taking andphysical examination are the most important pafis ofpreoperative pulmonary risk assessment (Table 6). Ahistory of exercise intolerance, chronic cough, orunexplained dyspnea should be obtained. Thephysical examination may identify findingssuggestive of unrecognized pulmonary disease.Among such findings, decreased breath sounds,dullness to percussion, wheezes, rhonchi, and a pro-longed expiratory phase predict an increase in therisk of pulmonary complications.l'

Since the publication of the first cardiac riskindex in 7977, clinicians have been aware of theimportance of, and the risk factors for, cardiaccomplications.l; Clinicians who care for patients inthe perioperative period may be surprised to iearnthat postoperative pulmonary complications areequally prevalent and contribute similarly tomorbidity, mortality, and length of stay. Forexample, in a large retrospective cohort study of8,930 patients undergoing hip fracture repair, 1,737(.790/o) patients had postoperative medicalcomplications. Serious pulmonary complications

occurred in 229 Q.6o/o) patients and serious cardiaccomplications occurred in 178 (2.0o/o) patients.

Any pulmonary infection should be treatedpreoperatively. Pulmonary complications may beprevented by providing patients with instructionson how to perform incentive spirometry and deep,breathing exercises. Deep-breathing exercises andincentive spirometry in the postoperative periodmay be particularly beneficial in obese patients, inpatients with lung disease and in patients undergo-ing abdominal or thoracic procedures.

PREOPERATTVEDIABETES ASSESSMENT

The most important perioperative risk attributable todiabetes mellitus is that of cardiac complications.The principal goal of the preparation of patientswith diabetes before surgery is a careful assessmentof cardiac risk, as discussed above. Diabetes alsoincreases the risk of surgical wound infections. Forthe subset of patients with diabetic neuropathy,there is additional risk for aspiration of gastriccontents during anesthesia if gastroparesis ispresent, and for blood pressllre liability duringsurgery if autonomic neuropathy exists.3

Thble 6

Patient-related risk factorsChronic obstructive pulmonary disease

Cigarette use <B weeks before surgery

ASA class >2

Goldman class 24aAge >60

Dependent functional status

Albumin <3,t) g/dL

Blood urea nitrogen >30 mg/dlAbnormal chest radiograph

Procedure-related risk factorSurgical site:- Thoracic surgery- Abdominal aortic aneurysm surgery- Upper abdominal surpIery- Neurosurgery- Peripheral vascular sllrgery

General anesthesia

Pancuronium use

Emergency surgery

Surgery lasting >J hours

PULMONARY RISK ASSESSMENT (MODIFIED FROM THE AMERICANSOCIETY OF AIIESTHESIOLOGISTS, I-A.ST AMENDED OCTOBER 1984."

CHAPTER 5 3l

Strategies to control blood sugar in the peri-operative period must balance the risk ofhyperglycemia due to the stress of surgery andanesthesia and the need for patients to fast beforesurgery that may increase the risk of hypoglycemia.One achieves this balance through frequentmonitoring and the use of short-acting insulin as

needed to achieve blood sugar goals. Optimalperioperative blood sugars are between 720 and200 mg/dL3 Patients who are diet-controlled mayproceed to surgery without additional treatment ofblood sugar other than careful perioperativemonitoring of blood sugar by fingerstick. Thosewho receive oral hypoglycemic agents should holdtheir medication on the morning of surgery.Intravenous fluids for oral agent- and insulin-treated patients should include glucose to decreasethe risk for lipolysis and ketone production.

PREOPERAITYENIUTRITION ASSESSMENT

Malnourished patients experience increased surgical

morbidity and mortality. A preoperative history andphysical examination includes an assessment of riskfactors for malnutrition, especially in the elderly.Social isolation, limited financial resources, poordentition, weight 1oss, and chronic disorders such as

pulmonary disease, congestive heart failure, depres-

sion, diarrhea, and constipation are commonlyassociated with malnutrition.' In acldition, patientsoften cannot eat for varying periods before and aftersurgery, further compromising nutritional status.

The most optimai means of defining a patient'snutritional status has not been established. However,if there are nutritional concerns, addltional factors

can be considered. A weight loss of more than 5%

in one month ot of l0o/o or more over stx months, aseftrm albumin of less than 3.2 g per dt (32 g per L),

and a total lymphoc),te count of less than J,000 perpL3 (3.0 3 109 per L) can signify an increased risk ofpostoperative compl ications.'

Effective assessment of the medical status ofpatient undergoing surgery, the physician shouldunderstand the risk associated with the particulartype of surgery planned and relate this risk to thepatient's undedying acute ancl chronic medical

problems. A detailed understanding of how thepresence of and severity of medical illnesscorrelates with an increased risk for perioperativecomplications will better serve our patients under-going elective podiatric surgery/.

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