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한국정맥경장영양학회지제 5 권제 1 호 2013 JKSPEN Vol. 5, No. 1, 2013 원저 췌십이장절제술환자의휴식대사량측정방법비교분석 1 전북대학교의학전문대학원외과학교실, 4 전북대학교생활과학대학식품영양학과 2 전북대학교병원영양집중지원팀, 3 전북대학교병원의생명연구원, 김선형 2,4 ㆍ유희철 1,2 ㆍ조백환 1,2 ㆍ채수완 3 ㆍ정미진 2 ㆍ최영란 2 ㆍ김행순 2 ㆍ김주신 2 ㆍ김숙배 4 A Comparison Between Measured and Predicted Resting Energy Expenditure of Pancreaticoduodenectomy Patients Seon Hyeong Kim 2,4, Hee Chul Yu, M.D. 1,2, Baik Hwan Cho, M.D. 1,2, Soo Wan Chae, M.D. 3, Mi Jin Jeong 2, Yeong Ran Choi 2, Haeng Sun Kim, Ph.D. 2, Ju Sin Kim, Ph.D. 2, Sook Bae Kim, Ph.D. 4 1 Department of Surgery, Chonbuk National University Medical School, 2 Nutrition Support Team, 3 Biomedical Research Institute, Chonbuk National University Hospital, 4 Department of Food Science and Human Nutrition, Chonbuk National University, Jeonju, Korea 교신저자 : 유희철, 전북대학교병원간담췌이식외과 561-712, 전주시덕진구건지로 20 Tel: 063-250-1576, Fax: 063-250-6197 E-mail: hcyu@jbnu.ac.kr 접수일 :2012 년 8 월 10 일, 수정일 :2012 년 9 월 23 일게재승인일 :2012 년 10 월 24 일본연구는 2010 년한국정맥경장영양학회에서대상 ( 주 ) 학술연구기금지원으로이루어졌음. Purpose: An accurate determination of energy expenditure is needed to prevent postoperative complications and provide effective medical care for surgical patients. The aim of this study was to compare measured resting energy expenditure (REE) in patients undergoing pancreaticoduodenectomy (PD) using an indirect calorimetry (IC) with the help of five predictive equations. Methods: The subjects chosen for the study were 18 patients (12 males, 6 females) who underwent PD at Chonbuk National University Hospital between March 2010 and October 2011. REE was measured by IC (IC REE) and calculated with the following five predictive equations - ( eq REE)-Harris-Benedict (HB), Mifflin St. Jeor (MI), American College of Chest Physician (AC), Ireton- Jones (IJ) and Cunningham (CU) equation - on postoperative day 3. Results: The mean measured REE by IC was 1,117.9 ±180.2, whereas the mean predicted REE by HB, MI, AC, IJ and CU equations were 1,241.3±156.1, 1,226±153.0, 1,401.7±188.0, 1,355.1±342.7, and 1,324.8±188.7 kcal/ day, respectively. The mean predicted REE by HB, MI, AC, IJ, and CU were found to be significantly different from the measured IC REE. The intraclass correlation coefficient (ICC), which describes the degree of agreement with the IC REE, was significantly highest in CU eq REE (r= 0.679). The rate of accuracy of HB eq REE, MI eq REE, AC eq REE, IJ eq REE, and CU eq REE for IC REE was 27.8%, 50.0%, 27.8%, 22.2%, and 23.5%, respectively, in individual subjects. Conclusion: The intraclass correlation coefficient (r= 0.124 0.679) and accuracy rate (22.2 50.0%) determined from the results of REE measured by IC and that calculated by five predictive equations were low in overall. The low accuracy rate of energy expenditure by equations, which apply uniform indicators, can be explained by ongoing metabolic changes of the patient. Thus, the use of IC is recommended to assess energy requirements in PD; when this method is not practical in clinical settings, nutrition intervention is needed through regular monitoring because of the low accuracy rate of the predictive methods and IC REE that can cause inappropriate energy management, leading to metabolic disorders. (JKSPEN 2013;5(1):24-30) Key Words: Indirect calorimetry, Rest energy expenditure, Predictive energy expenditure, Equation 중심단어 : 간접열량측정기, 휴식에너지소비량, 예측에너지소비량, 공식 서 수술환자의영양상태는수술후예후, 합병증, 유병률및재원기간등에영향을미친다. 에너지부족은수술부위와상처의회복지연, 면역기능약화및호흡기의존기간을연장시키고, 에너지의과잉공급은고혈당, 전해질불균형, 고지혈증, 폐기능부전등의합병증을유발시킬수있으므로정확한에너지요구량산정을통한적절한영양중재는치료의중요한요소이다. 1,2 췌십이지장절제술 (pancreaticoduodenectomy, PD) 은영양소소화흡수와직접적으로연관된다장기 (muti-organs) 를절제, 재건하는수술로서다장기기능부전및인슐린저항의증가로설사, 복부경련, 과량의가스생산, 위배출지연 론 24

김선형외 : 췌십이장절제술환자의휴식대사량측정방법비교분석 25 (delayed gastric emptying) 등의합병증에따른영양불량위험성이높다. 그러나최근연구들은 3,4 영양지원등적극적인영양중재를통해장운동시작, 재원일및퇴원후회복기간등의단축효과를보여주고있어 PD환자에서영양관리가중요시되고있다. 에너지요구량을결정하는최적의방법은간접열량측정기 (indirect calorimetry, IC) 를이용한산정이지만, 장비구입비용이고가이며시간, 공간적제한과사용절차의번거로움으로훈련된인력이요구된다. 5 이에실제임상에서는간편하고경제적이며사용하기용이한공식들을기관들의선호에따라선정하여이용하고있다. 그러나공식을이용한산정방법은공식의종류와평가자에따른스트레스, 손상계수등의고려계수가다를수있어산정한에너지요구량에차이가있다. 이에본연구는 PD 환자를대상으로간접열량측정기에의한휴식대사량과임상에서널리사용되고있는 5가지공식 (Harris-Benedict, Mifflin, American College of Chest Physician, Ireton-Jones, Cunningham) 으로산정한휴식대사량을비교분석하여간접열량측정기와근접하는공식을알아보고자한다. 대상및방법연구대상자는전북대학교병원에서 PD를시행한 18명 ( 남 12명, 여 6명 ) 으로하였다. 연구참가자는 29명이며 PD 를계획하였으나실제 PD를시행하지못한환자 4명, 수술후 3일째연구참가를거부한환자 2명, 수술후 3일째혈액역동학적불안정환자 4명, 수술직전수술을거부한환자 1명을포함한 11명의중도탈락자가발생하였다. 18세미만, 낭포성섬유종, 발열, 마비 (quatraplegia, paraplegia) 가있거나카테콜라민, 진정제, 근육이완제가처방된대상자는기초대사량에영향을미칠수있어제외하였다. 본연구는전북대학교병원임상시험위원회 (Institutional Review Board) 의승인을얻고환자의동의를받아 2010년 3월부터 2011년 10월까지시행하였다. 대상자는수술후 3일째 IC (Vmax 29n; Sensor Medics Co., Yorba Linda, CA, USA) 에의한휴식에너지소비량 (Resting Energy Expenditure measured Indirect Calorimetry, IC REE) 측정과수술전날 Bio Impedence Analyzer (Inbody720; Biospace Co., Seoul, Korea) 에의한제지방량 (fat free mass), 신장 (height), 체중 (weight) 을측정한후공식에적용하여에너지요구량을산정하였고체질량지수 (body mass index, BMI) 는체중을신장의제곱으로나누어계산하였다 (kg/m 2 ). 성별, 나이, 진단명, 수술및입원일수등의일반적특징과약제사용여부는의무기록지를검토하였고영양공급경로및공급량에대한정보조사는의무기록지와 24시간회상법을이용한환자및보호자와의면담을통하여수집하였다. 1. 간접열량측정기간접열량측정기는제조사의권고에따라측정시마다가스분석기를보정하였다. 측정 5시간전부터금식하였고지속적으로주입되는영양소와약물의주입속도는 12시간전부터일정하게유지시켰다. 또한측정전 30분동안휴식을취하며호흡계수변화율 <5%, 산소소비량과이산화탄소발생량의변화율 <10% 로 5분이상지속적으로유지되는평형상태 (steady state) 에서반듯하게누운자세로 30분동안측정하였다. 측정오차를줄이기위해전담연구원 1명이적정실내온도 (thermoneural) 가유지되는전용병실에서측정하였다 (Fig. 1). 6 2. 휴식대사량산정공식신체계측, 또는의무기록지를통하여용이하게얻을수있는체중, 신장, 나이등을적용하는 Harris-Benedict (HB), 7 Fig. 1. Picture of indirect calorimetry and take a measurement.

26 한국정맥경장영양학회지제 5 권제 1 호 2013 Mifflin. St. Jeor (MI), 8 American College of Chest Physician (AC), 9 Ireton-Jones (IJ) 10 공식과제지방량을이용하는 Cunningham (CU) 11 공식으로휴식대사량 (predictiive equations for resting energy expenditure, eq REE) 을산정하였다 (Table 1). 3. 통계분석통계처리는 PASW Statistics (version 18.0; IBM Co., Armonk, NY, USA), SAS (version 9.2; SAS Inc., Cary, NC, USA) 를이용하여분석하였다. 연구대상자의 IC REE 에대한 HB eq REE, MI eq REE, AC eq REE, IJ eq REE, CU eq REE의비교와일치도를알아보기위해 paired t-test, intraclass correlation coefficient (ICC), Bland-Altman 12 분석방법을사용하였다. 각공식의정확도는대상자개인별의 eq REE를 IC REE 와비교하여 eq REE가 IC REE 의 90 110% 는적절공급, IC REE 의 110% 초과는과잉공급, IC REE 의 90% 미만은부족공급으로구분하며 eq REE가 IC REE 의 90 110% 를보여주는적절공급대상자수의백분율 (%) 로나타낸다. 13 통계적유의수준은 0.05로하였다. Table 1. Predictiive equations for REE (kcal/day) 결 과 Equation Harris-Benedict Mifflin American College of Chest Physician Ireton-Jones Cunningham Table 2. Demographic and anthropometric data Measurement Formula ( eq REE) 13.75 (W)+5 (H)-6.8 (A)+66 in male 9.6 (W)+1.8 (H)-4.7 (A)+655 in female 10 (W)+6.25 (H) 5 (A)+5 in male 10 (W)+6.25 (H) 5 (A)-161 in female 25 kcal/kg actual wt in non-obese subject 25 kcal/kg adjust wt in obese subject 629-(11A)+(25W) in non-obese subject 629-(11A)+(25W)-609 in obese subject 370+(21.6 FFM) REE = resting energy expenditure; W = weight (kg); H = height (cm); A = age (yr); FFM = fat free mass (kg). Sex (male/female) Age (yr) Weight (kg) Height (cm) Ideal body weight (kg) Fat free mass (kg) BMI (kg/m 2 ) Underweight 1 Adequate Overweight Obese Diagnosis Pancreatic head carcinoma Ampulla of vater carcinoma Distal common bile duct carcinoma Operation procedure Pylorus preserving pancreaticoduodenectomy Whipple procedure Data (N=18) 12/6 62.5±12.5 59.4±8.9 160.5±7.3 56.5±5.5 44.2±8.7 23.0±2.7 1 (5.6) 11 (61.1) 6 (33.3) 0 (0) Values are presented as mean±standard deviation, number (%), or number only. 1 Classified according to the criteria of the World Health Organization body mass index (BMI) <18.5 is underweight, BMI 18.5 24.9 is adequate, BMI 25 29.9 is overweight, BMI >30 is obese. 6 5 7 12 6 대상자 18명 ( 남 12명, 여 6명 ) 의평균연령은 62.5±12.5세이며, 실제체중 59.4±8.9 kg, 신장 160.5±7.3 cm, 표준체중 56.5±5.5 kg, 제지방량 44.2±8.7 kg, BMI는 23.0±2.7 kg/m 2 였다. 세계보건기구의비만분류기준에따른 BMI<18.5의저체중은 1명 (5.6%), BMI 18.5-24.9의적정체중 11명 (61.1%), BMI 25-29.9의과체중 6명 (33.3%), BMI>30의비만은 0명 (0.0%) 이다. 주진단명은췌두부암 6명, 팽대부암 5명, 원위부총담관암 7명이며그중 12명은유문보존췌십이지장절제술 (pylorus preserving PD), 6명은휘플 (Whipple's) 수술을시행하였다 (Table 2). 영양공급경로및공급량은수술전날에정맥영양을공급받은환자는 12명, 경구섭취와정맥영양을병행한환자는 1 명, 금식은 5명이었으며평균에너지공급량은 875 kcal/day이다. 수술후 3일째는 18명모두경구섭취와정맥영양을병행하였으며평균영양공급량은 1,050 kcal/day이다 (Table 3). 수술후 3일째측정한 IC REE 평균값과비교공식들간의평균값은 HB, MI, AC, IJ, CU에서각각 1,117.9±180.2, 1,241.3± 156.1, 1,226±153.0, 1,401.7±188.0, 1,355.1±342.7, 1,324.8±188.7 kcal/day이며체중당휴식대사량은각각 19.1±3.6, 20.9±1.6, 20.7±2.2, 23.6±1.7, 23.9±2.4, 20.9±5.9 kcal/kg/day이다. IC REE 에대한공식들의평균값비교시모든공식에서유의한차이가있었다. 체중당 REE (kcal/kg/day) 분석에서 Table 3. Nutrition route andtotal energy intake (18 patients) Variable Nutrition route Parenteral Parenteral+oral NPO Total energy intake (kcal/day) NPO = nil per os = Nothing By Mouth. Preoperative day 1 12 1 5 875 Preoperative day 3 0 15 3 1,050

김선형외 : 췌십이장절제술환자의휴식대사량측정방법비교분석 27 Indirect calotimetry (IC eq REE) Harris-Benedict (HB eq REE) Mifflin (MI eq REE) American College of Chest Physician (AC eq REE) Ireton-Jones (IJ eq REE) Cunningham (CU eq REE) Table 4. Average REE of measured IC and predicted equations Resting energy expenditure Paired t-test kcal/day kcal/kg/day P-value 1 P-value 2 1,117.9±180.2 1,241.3±156.1 1,226.0±153.0 1,401.7±188.0 1,355.1±342.7 1,324.8±188.7 19.1±3.6 20.9±1.6 20.7±2.2 23.6±1.7 23.9±2.4 20.9±5.9-0.0151 0.0101 0.0001 0.0083 0.0010 Values are presented as mean±standard deviation. 1 Comparison mean REE of kcal/day between measured (IC eq REE) and predicted (HB eq, MI eq, AC eq, IJ eq E, CU eq ) REE. 2 Comparison mean REE of kcal/day/kg between measured (IC eq REE) and predicted (HB eq, MI eq, AC eq, IJ eq, CU eq ) REE. Statistically significant: P<0.05. REE = resting energy expenditure. - 0.0299 0.0137 0.0001 0.0004 0.2709 Appropriate 1 Overfeeding Underfeeding Table 5. Accuracy rate of the equations (percentage of predicted 10% different from IC REE measured) HB eq REE MI eq REE AC eq REE IJ eq REE CU eq REE 2 27.8 (5) 61.1 (11) 11.1 (2) 50.0 (9) 50.0 (9) (0) 27.8 (5) 72.2 (13) (0) 22.2 (4) 61.1 (11) 16.7 (3) 23.5 (4) 76.5 (13) (0) Values are presented as percentage (number). 1 Appropriate feeding, overfeeding, underfeeding means the patient received 90 110%, >110%, <90% of measured REE, respectively. 2 Number of patients is 17 rejected measurement of BIA (fat free mass). IC = Indirect calotimetry; REE = resting energy expenditure; HB = Harris-Benedict; MI = Mifflin; AC = American College of Chest Physician; IJ = Ireton-Jones; CU = Cunningham. Table 6. ICC between of measured IC and predicted equations 95% CI Equations ICC (r) 1 Harris-Benedict (HB eq REE) Mifflin (MI eq REE) American College of Chest Physician (AC eq REE) Ireton-Jones (IJ eq REE) Cunningham (CU eq REE) 0.340 0.551 0.124 0.241 0.679 Lower bound 511.0 424.8 771.5 911.7 510.3 Upper bound 264.1 280.7 203.9 437.3 88.2 P-value One-way random effects model where people effects are random. 1 0 1 represents the value of the agreement degree is the closer 1 to the higher: 0 0.2 indicates poor agreement: 0.3 0.4 indicates fair agreement; 0.5 0.6 indicates moderate agreement; 0.7 0.8 indicates strong agreement; and >0.8 indicates almost perfect agreement. Statistically significant: P<0.05. ICC = intraclass correalation coefficient; CI = confidence interval; REE = resting energy expenditure. 0.077 0.007 0.397 0.160 0.001 IC REE 에대한공식들의비교값은 HB eq REE, MI eq REE, AC eq REE, IJ eq REE에서유의한차이가있었으나 CU eq REE에서는유의한차이가없었다 (Table 4). 각공식별정확도는 HB eq REE 27.8%, MI eq REE 50%, AC eq REE 27.8%, IJ eq REE 22.2%, CU eq REE 23.5% 로 MI eq REE가가장높은정확도를보였다 (Table 5). IC REE 과공식산출값 ( eq REE) 의일치도를나타내는 ICC는 CU (r=0.679), MI (r=0.551), HB (r=0.340), IJ (r=0.241), AC (r=0.124) 순서로높은값을보여주고있으며 CU, MI는유의적으로높은일치도를보여주고있으나나머지공식에서는낮게 (r=0.340-0.124) 나타났다 (Table 6). Fig. 2는 IC REE 와 HB eq REE, MI eq REE, AC eq REE, IJ eq REE, CU eq REE 개인별일치도의비교를그림으로나타내는 Bland-Altman 분석결과이다 (r=0.340, P=0.077).

28 한국정맥경장영양학회지제 5 권제 1 호 2013 Fig. 2. Bland-Altman analysis for comparison of agreement between resting energy expenditure (REE) measured by indirect calorimetry and predicted REE using (A) Harris-Benedict, (B) Mifflin St. Jeor, (C) American College of Chest Physician, (D) Ireton-Jones, (E) Cunningham equations. The horizontal lines represent +2SD, mean, and -2SD of the differences between measured and predicted REE. 고찰적절한영양공급은급성기의단백질, 백혈구, 콜라겐등의조직구성물질을합성하여상처를회복시키므로, 수술 후합병증예방과효과적인치료를위해영양관리가필요하다. 특히, 적절한에너지공급은면역기능강화, 호흡및간기능을정상화시켜유병률및사망률을향상시키므로적정에너지요구량산정이요구된다. 14 PD는영양소소화흡

김선형외 : 췌십이장절제술환자의휴식대사량측정방법비교분석 29 수및대사에직접적으로연관된기관 (organs) 들을절제재건하는수술로다양한합병증과수술스트레스로인한영양불량가능성이높다. 효과적인영양공급을위해정확한영양판정및영양요구량산정이필요하며특히적정에너지요구량산정이요구된다. 이에정확도가높은간접열량측정기의이용을권장되나실제임상에서는자료수집이용이한지표를적용하는공식들을주로사용하고있다. 적절한에너지공급을위하여 IC를대체할수있는공식을비교분석한연구들을살펴보면다음과같다. HB eq REE의 IC REE 비교연구에서 Osborne 등 15 은심장수술후중환자에게 IC REE 대신 HB eq REE를권장하기도하였으나, Faria 등 16 은 25% 환자가 IC REE 의 90 110% 이내로적정하게공급받으며 32 93% 는과잉공급, 12 36% 는부족하게공급받는다고하였다. 또한 Martins 등 2 의연구에서는 IC REE 에대한 HB eq REE의낮은상관관계 (r=0.57), 오차범위 10 28% 로 IC를대체할수없는큰오차값이라하였다. 여러연구를종합하면 HB eq REE의정확도는 17 67% 이며 17-19 본연구에서도 27.8% 정확도로낮은정확도를보여주고있다. MI 공식은 1990년건강인대상으로개발되었으며 Frankenfield 등 18 의연구에서는중환자대상 MI eq REE와 IC REE 비교연구에서 25% 의낮은정확도를보여주고있으나 Faria 등 16 의연구에서는 MI 공식이 IC를대체할만하다고하였다. Frankenfield 등 19 은 MI 공식이다른공식에비해가장정확도가높으나모든연령, 인종에일반화하기에는오류와제한점이있음을보고하고있다. 본연구에서는 50% 의정확도와 ICC, r=0.551의일치도로다른공식에비하여유의적으로높은값을보여주고특히정확도는사용한공식중가장높았다. IJ 공식은 1992년화상환자를포함한대상으로만들어졌으며 Walker와 Heuberger 17 는중환자에서 IC를대체할수있는방법으로권장하였고정확도는 28 83%, 젊은연령과비만환자에게서더욱높은값을보였다고보고하였다. IC REE 에대한 IJ eq REE의연구들을분석한 Frankenfield 등 20 은대체적으로 60% 의정확도를나타낸다고보고하고있으나본연구에서는 22.2% 의낮은정확도를보여주고있다. AC 공식은 1997년미국폐전문의학회 (American College of Chest Physicians) 에서대부분의환자의에너지요구량산정을위하여평소체중 ( 비만인경우에는조정체중 ) 의 25 kcal/kg 을권장하고있다 9. Reid 21 와 Frankenfield 등 18 은 AC eq REE을이용한분석에서각각 18%, 46% 의정확도를보고하고있으며본연구에서도 27.8% 의낮은정확도를보여주고있다. CU 공식은제지방을이용하여에너지를산정하는방법으로 Bauer 등 22 은췌장암환자대상연구에서 IC REE 에대한 HB, MI, CU eq REE은대상자전체의평균값을예측하기에적 당하고특히 CU eq REE의경우개인별비교시 ICC r=0.836로일치도가높아 IC를대체할만하다고하였으며본연구에서도 r=0.679로제일높은상관값을나타내고있으나정확도는 23.5% 로낮은값을보여주고있다. IC REE 와 eq REE의비교한이번연구에서대상자평균휴식대사량값 (kcal/day) 은 HB, MI, AC, IJ, CU 모든공식에서유의한차이를보이고평균체중당휴식대사량값 (kcal/kg/ day) 또한 CU 공식을제외한나머지공식에서차이를보이고있다. IC REE 와 eq REE의일치도를나타내는 ICC값은 MI, CU, HB, AC, IJ 순서로높게나타났으나 CU (r=0.679), MI (r=0.551) 의개인별정확도가각각 23.5%, 50.0% 로대체로낮은값을보여주고있다. 이는각공식을만들때대상자특성이다르고, 특히환자의지속적인대사변화와다양한질병상태로인해일률적인지표를적용하는공식에의한에너지요구량의정확도는낮게나타난것이다. 그러므로 PD환자의적절한에너지공급을위하여 IC 이용을권장하나, 공식을사용해야하는경우위 5가지공식이 IC를대체하기에는 IC REE 와의 ICC 및정확도가낮아부적절에너지공급으로인한대사장애가유발될수있으므로정기적인모니터링을통한영양중재가필요하다. 본연구는대상자수가적어의미있는결과를기대하기에제한점을갖고있다. 합병증이없는소화기계수술환자는수술후 1 3일이내에혈액역동학적안정기와수분균형을이루므로 23 정확한체중과제지방량의측정을위하여이번연구에서는수술후 3일째 IC REE 를측정하였다. 그러나수술전연구에참가동의한환자가수술후 3일째질병및정신적안정기에이르지못하여중도탈락하는경우가발생하여연구대상자의부족요인이되었다. 위의제한점에도불구하고본연구는 PD환자를대상으로 IC REE 와공식산출값을비교한연구이며, 적합한공식에대한지속적인연구가필요한실정으로추후 PD환자의에너지공급을위한지침마련을위해필요한자료를제공할수있으리라생각된다. 결론 IC 측정값과 5가지에너지요구량산정공식에의한휴식대사량비교결과 CU, MI 공식을이용한산출값에서가장높은일치도 (r=0.679, 0.551) 를보여주고있으나 5가지공식에서전반적으로낮은일치도 (r=0.124 0.679) 와정확도 (22.2 50.0%) 를보여주고있다. 그러므로 PD환자대상으로정확한에너지요구량의공급을위하여 IC의이용을권장하나부득이공식을사용하는경우에는부적절한에너지공급으로인한대사장애를유발하지않도록정기적인모니

30 한국정맥경장영양학회지제 5 권제 1 호 2013 터링을통한영양중재가요구된다. REFERENCES 1. Kemper M, Weissman C, Hyman AI. Caloric requirements and supply in critically ill surgical patients. Crit Care Med 1992;20(3):344-8. 2. Auxiliadora Martins M, Menegueti MG, Nicolini EA, Picolo MF, Lago AF, Martins Filho OA, et al. Energy expenditure in critically ill surgical patients. Comparative analysis of predictive equation and indirect calorimetry. Acta Cir Bras 2011;26 Suppl 2:51-6. 3. Pappas S, Krzywda E, McDowell N. Nutrition and pancreaticoduodenectomy. Nutr Clin Pract 2010;25(3):234-43. 4. Lassen K, Kjaeve J, Fetveit T, Tranø G, Sigurdsson HK, Horn A, et al. Allowing normal food at will after major upper gastrointestinal surgery does not increase morbidity: a randomized multicenter trial. Ann Surg 2008;247(5):721-9. 5. Wooley JA. Indirect calorimetry: applications in practice. Respir Care Clin N Am 2006;12(4):619-33. 6. Haugen HA, Chan LN, Li F. Indirect calorimetry: a practical guide for clinicians. Nutr Clin Pract 2007;22(4):377-88. 7. Harris JA, Benedict JA. Biometric studies of basal metabolism in man. Carnegie Institute of Washington, DC; 1919; publication no 270. 8. Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr 1990;51(2): 241-7. 9. Cerra FB, Benitez MR, Blackburn GL, Irwin RS, Jeejeebhoy K, Katz DP, et al. Applied nutrition in ICU patients. A consensus statement of the American College of Chest Physicians. Chest 1997;111(3):769-78. 10. Ireton-Jones C, Jones JD. Improved equations for predicting energy expenditure in patients: the Ireton-Jones Equations. Nutr Clin Pract 2002;17(1):29-31. 11. Cunningham JJ. Body composition as a determinant of energy expenditure: a synthetic review and a proposed general prediction equation. Am J Clin Nutr 1991;54(6):963-9. 12. Bland JM, Altman DG. Measuring agreement in method comparison studies. Stat Methods Med Res 1999;8(2):135-60. 13. Weijs PJ, Kruizenga HM, van Dijk AE, van der Meij BS, Langius JA, Knol DL, et al. Validation of predictive equations for resting energy expenditure in adult outpatients and inpatients. Clin Nutr 2008;27(1):150-7. 14. Thorell A, Nygren J, Ljungqvist O. Insulin resistance: a marker of surgical stress. Curr Opin Clin Nutr Metab Care 1999; 2(1):69-78. 15. Osborne BJ, Saba AK, Wood SJ, Nyswonger GD, Hansen CW. Clinical comparison of three methods to determine resting energy expenditure. Nutr Clin Pract 1994;9(6):241-6. 16. Faria SL, Faria OP, Menezes CS, de Gouvêa HR. de Almeida Cardeal M. Metabolic profile of clinically severe obese patients. Obes Surg 2012;22(8):1257-62. 17. Walker RN, Heuberger RA. Predictive equations for energy needs for the critically ill. Respir Care 2009;54(4):509-21. 18. Frankenfield DC, Coleman A, Alam S, Cooney RN. Analysis of estimation methods for resting metabolic rate in critically ill adults. JPEN J Parenter Enteral Nutr 2009;33(1):27-36. 19. Frankenfield D, Roth-Yousey L, Compher C. Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults: a systematic review. J Am Diet Assoc 2005;105(5):775-89. 20. Frankenfield D, Smith JS, Cooney RN. Validation of 2 approaches to predicting resting metabolic rate in critically ill patients. JPEN J Parenter Enteral Nutr 2004;28(4):259-64. 21. Reid CL. Poor agreement between continuous measurements of energy expenditure and routinely used prediction equations in intensive care unit patients. Clin Nutr 2007;26(5):649-57. 22. Bauer J, Reeves MM, Capra S. The agreement between measured and predicted resting energy expenditure in patients with pancreatic cancer: a pilot study. JOP 2004;5(1):32-40. 23. Nishioka M, Ishikawa M, Hanaki N, Kashiwagi Y, Miki H, Miyake H, et al. Perioperative hemodynamic study of patients undergoing abdominal surgery using pulse dye densitometry. Hepatogastroenterology 2006;53(72):874-8.