title: Differences in resuscitation in morbidly obese burn patients may contribute to high mortality.
abstract: The rising number of obese patients poses new challenges for burn care. These may include adjustments in calculations of burn size, resuscitation, ventilator wean, nutritional goals as well as challenges in mobilization. The authors have focused this observational study on resuscitation in the obese patient population in the first 48 hours after burn injury. Previous trauma studies suggest a prolonged time to reach end points of resuscitation in the obese compared to nonobese injured patients. The authors hypothesize that obese patients have worse outcomes after thermal injury and that differences in the response to resuscitation contribute to this disparity. The authors retrospectively analyzed data prospectively collected in a multicenter trial to compare resuscitation and outcomes in patients stratified by National Institutes of Health/World Health Organization body mass index (BMI) classification (BMI: normal weight, 18.5-24.9; overweight, 25-29.9, obese, 30-39.9; morbidly obese, ≥40). Because of the distribution of body habitus in the obese, total burn size was recalculated for all patients by using the method proposed by Neaman and compared with Lund-Browder estimates. The authors analyzed patients by BMI class for fluids administered and end points of resuscitation at 24 and 48 hours. Multivariate analysis was used to compare morbidity and mortality across BMI groups. The authors identified 296 adult patients with a mean TBSA of 41%. Patient and injury characteristics were similar across BMI categories. No significant differences were observed in burn size calculations by using Neaman vs Lund-Browder formulas. Although resuscitation volumes exceeded the predicted formula in all BMI categories, higher BMI was associated with less fluid administered per actual body weight (P = .001). Base deficit on admission was highest in the morbidly obese group at 24 and 48 hours. Furthermore, the morbidly obese patients did not correct their metabolic acidosis to the extent of their lower BMI counterparts (P values .04 and .03). Complications and morbidities across BMI groups were similar, although examination of organ failure scores indicated more severe organ dysfunction in the morbidly obese group. Compared with being normal weight, being morbidly obese was an independent risk factor for death (odds ratio = 10.1; confidence interval, 1.94-52.5; P = .006). Morbidly obese patients with severe burns tend to receive closer to predicted fluid resuscitation volumes for their actual weight. However, this patient group has persistent metabolic acidosis during the resuscitation phase and is at risk of developing more severe multiple organ failure. These factors may contribute to higher mortality risk in the morbidly obese burn patient.
authors: From the *University of Washington Medicine Regional Burn Center at Harborview Medical Center, Seattle; †University of Texas Southwestern Parkland Memorial Hospital, Dallas; ‡Loyola University Medical Center, Maywood, Illinois; §Massachusetts General Hospital, Boston; and ‖University of Texas Medical Branch, Galveston.
authors: Lisa
authors: L
authors: Rae
authors: Tam N
authors: TN
authors: Pham
authors: Gretchen
authors: G
authors: Carrougher
authors: Shari
authors: S
authors: Honari
authors: Nicole S
authors: NS
authors: Gibran
authors: Brett D
authors: BD
authors: Arnoldo
authors: Richard L
authors: RL
authors: Gamelli
authors: Ronald G
authors: RG
authors: Tompkins
authors: David N
authors: DN
authors: Herndon
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D002056:Burns / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy; D002423:Cause of Death; D015331:Cohort Studies; D005260:Female; D005440:Fluid Therapy / Q000379:methods; D017052:Hospital Mortality / Q000639:trends*; D006801:Humans; D015601:Injury Severity Score; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D009102:Multiple Organ Failure / Q000175:diagnosis / Q000401:mortality / Q000628:therapy; D015999:Multivariate Analysis; D009767:Obesity, Morbid / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy; D011237:Predictive Value of Tests; D012151:Resuscitation / Q000379:methods* / Q000401:mortality*; D012189:Retrospective Studies; D018570:Risk Assessment; D018805:Sepsis / Q000175:diagnosis / Q000401:mortality / Q000628:therapy; D016019:Survival Analysis
references: JAMA. 2013 Jan 2;309(1):71-82
references: 23280227
references: J Am Coll Surg. 2006 Oct;203(4):533-8
references: 17000398
references: J Trauma. 2010 Feb;68(2):317-30
references: 20154544
references: J Burn Care Res. 2011 May-Jun;32(3):421-8
references: 21562463
references: Intensive Care Med. 2004 Mar;30(3):437-43
references: 14767583
references: J Burn Care Res. 2007 Jul-Aug;28(4):555-65
references: 17665515
references: Ann Surg. 2007 Apr;245(4):622-8
references: 17414612
references: Crit Care Med. 2008 Jan;36(1):151-8
references: 18007266
references: J Trauma. 1992 Dec;33(6):818-20
references: 1474621
references: Contrib Nephrol. 2004;144:329-49
references: 15264421
references: N Engl J Med. 2010 Dec 2;363(23):2211-9
references: 21121834
references: J Trauma. 2000 Sep;49(3):567-8
references: 11003341
references: Arch Surg. 2004 Sep;139(9):983-7
references: 15381617
references: J Trauma Acute Care Surg. 2013 Jan;74(1):282-8
references: 23271104
references: J Burn Care Res. 2009 Nov-Dec;30(6):957-66
references: 19826270
references: J Trauma. 2011 Feb;70(2):292-8
references: 21307724
references: Shock. 2012 Mar;37(3):253-6
references: 22266966
references: Am Surg. 2002 Aug;68(8):689-93; discussion 693-4
references: 12206603
references: J Burn Care Rehabil. 1997 Sep-Oct;18(5):402-5
references: 9313119
references: J Burn Care Res. 2006 Jul-Aug;27(4):448-51
references: 16819346
references: J Burn Care Rehabil. 1990 Jan-Feb;11(1):32-4
references: 2312589
references: J Am Coll Surg. 2006 Oct;203(4):539-45
references: 17000399
references: Chest. 2003 Apr;123(4):1202-7
references: 12684312
references: Crit Care. 2011;15(1):R16
references: 21232094
references: Intensive Care Med. 2009 Jul;35(7):1152-70
references: 19189078
references: Crit Care Med. 2010 Jan;38(1):51-8
references: 19661803
references: Nutr Clin Pract. 2011 Oct;26(5):593-7
references: 21947642
references: Burns. 2011 Mar;37(2):208-14
references: 21129850