Energy Expenditure and Caloric Balance After Burn: Increased Feeding Leads to Fat Rather Than Lean Mass Accretion

OBJECTIVE: Resting energy expenditure (REE) is commonly measured in critical illness to determine caloric "demands" and thus nutritive needs. SUMMARY BACKGROUND DATA: The purpose of this study was to 1) determine whether REE is associated with clinical outcomes and 2) determine whether an optimal caloric delivery rate based on REE exists to offset erosion of lean mass after burn. METHODS: From 1995 to 2001, REE was measured by indirect calorimetry in 250 survivors of 10 to 99%TBSA burns. Caloric intake and REE were correlated with muscle protein catabolism, length of stay, ventilator dependence, sepsis, and mortality. From 1998 to 2000, 42 patients (>60%TBSA burns) received continuous enteral nutrition at a spectrum of caloric balance between 1.0x REE kcal/d -1.8x REE kcal/d. Serial body composition was measured by dual energy x-ray absorptiometry. Lean mass, fat mass, morbidity, and mortality were determined. RESULTS: REE/predicted basal metabolic rate correlated directly with burn size, sepsis, ventilator dependence, and muscle protein catabolism (P <.05). Declining REE correlated with mortality (P <.05). 2) Erosion of lean body mass was not attenuated by increased caloric balance, however, fat mass increased with caloric supply (P <.05). CONCLUSION: In surviving burned patients, caloric delivery beyond 1.2 x REE results in increased fat mass without changes in lean body mass. Declining energy expenditure appears to be a harbinger of mortality in severely burned patients.     

Metabolic effects of growth hormone treatment: an early predictor of growth response?

Fourteen children receiving one year of recombinant human growth hormone (rhGH) treatment underwent measurement of serial changes in body composition (measured by skinfold thickness, bioelectrical impedance, and H2(18)O dilution), resting energy expenditure (REE, estimated by ventilated hood indirect calorimetry), and total free living daily energy expenditure (TEE, measured by the doubly labelled water technique). Mean height velocity increased from 4.9 to 8.6 cm/year after six months of treatment. Fat free mass (FFM) increased more during the first six weeks (24.4 g/day) than from six to 26 weeks of treatment (6.8 g/day); fat mass decreased by 7.2 g/day and 1.1 g/day respectively. The six week increase in REE (kJ/day) was maintained after six months of treatment, though expressed per kilogram FFM (kJ/kgFFM/day), returned to pretreatment values by three months. Height velocity increases at six months correlated with six week changes in fat mass measured by skinfold thickness and REE, though use of this relationship to predict growth response in individuals is limited by the wide 95% prediction intervals. No significant changes in growth, body composition, or energy expenditure were observed between six and 12 months of treatment, in either patients who had initially responded well to treatment or those who were poor initial responders to treatment and who had their dose of rhGH doubled after six months.     

Neonatal stroke: Clinical characteristics and cerebral blood flow velocity measurements

The clinical courses of 8 term infants with focal cerebral infarction or neonatal stroke were studied to determine whether such infants can be identified by current markers of perinatal distress, and whether changes in cerebral blood flow velocity (CBFV) occur during the acute phase of the disease. CBFV was measured from the middle cerebral artery (MCA) and anterior cerebral artery (ACA) utilizing duplex Doppler. Seven of the 8 patients required no resuscitation in the delivery room; 1 infant required brief bag and mask ventilation. No infant had evidence of severe fetal acidemia (i.e., cord pH <7). All 8 infants were initially admitted to the newborn nursery. Infants were identified on the basis of abnormal clinical findings observed during the first 48 hours: seizures (n = 6) and hypotonia and apnea (n = 2). Serum electrolytes, calcium, magnesium, and glucose levels were normal, and the sepsis evaluation including a spinal tap was sterile in all patients. Neuroimaging revealed nonhemorrhagic left focal MCA infarction (n = 6) and right focal MCA infarction (n = 2). Duplex Doppler demonstrated transient ipsilateral decreases in CBFV as compared to the contralateral unaffected side at clinical presentation in 4 infants. In 2 of these infants the decrease in CBFV involved both the MCA and ACA, and in 2 infants, only the MCA vessels. These side-to-side differences were not present at subsequent CBFV measurements. The data indicate that infants who develop neonatal stroke cannot be distinguished from infants who do not develop the lesion by current markers of perinatal distress. Because neonatal stroke frequently occurs as an unanticipated event, prevention may not be possible.     

Clinical Predictors of Sleep Apnea in Patients Undergoing Bariatric Surgery

Background: Sleep apnea is a frequent and unappreciated condition of morbidly obese patients. If unrecognized it could lead to significant postoperative complications. A clinical tool to assess the severity of sleep apnea is not available.We prospectively determined whether the Epworth Sleepiness Scale (ESS) or body mass index (BMI) predict the severity of sleep apnea in morbidly obese patients. Methods: 66 consecutive patients evaluated for bariatric surgery from June to November 1999 were examined and prospectively administered a health questionnaire including the ESS. Patients with an ESS ≥ 6 were referred for polysomnography with calculation of Respiratory Disturbance Index (RDI). Sleep apnea was graded as mild (RDI 6-20), moderate (RDI 21-40) and severe (RDI>40). Clinical variables such as BMI and ESS score were compared using regression analysis. Data are mean ± SEM. Results: 4 men and 23 women (27/66) who scored >6 on the ESS completed a sleep study. Mean ESS was 13 ± 4.5. Sleep apnea was mild in 13 patients, moderate in 7, severe in 6, and absent in 1. Mean age was 43 ± 9.5 years. BMI was 52 ± 10 kg/m². Linear regression analysis did not demonstrate correlation between ESS score and severity of sleep apnea (r²=0.03, p>0.05). Multiple regression analysis demonstrated no correlation between BMI, patient snoring, and RDI score. Conclusions: Sleep apnea is frequent in candidates screened for bariatric surgery. ESS is a useful tool to investigate daytime sleepiness and other manifestations of sleep apnea. However, the ESS does not predict the severity of sleep apnea. Clinical suspicion of sleep apnea should prompt polysomnography.     

Community‐Based Practice Experience of Unsuspected Breast Magnetic Resonance Imaging Abnormalities Evaluated With Second‐Look Sonography

Objective. The purpose of this study was to assess the utility and efficacy of second‐look breast sonography in the evaluation of abnormalities identified on presurgical breast magnetic resonance imaging (MRI) examinations. Methods. A retrospective review was performed of 152 presurgical breast MRI examinations having 196 unsuspected abnormalities to identify findings that underwent subsequent breast sonography. Eligible examinations had a suspicious abnormality identified on presurgical MRI and documentation of the location and size of the finding on MRI and subsequent second‐look sonography. Fourteen examinations not meeting the criteria were excluded, with 182 abnormalities remaining. Patient medical records were reviewed. Results. Seventy percent (128 of 182) of breast MRI lesions were visible at second‐look sonography; 30% (54 of 182) were sonographically occult. Ninety‐five percent (121 of 128) of sonographically visible abnormalities underwent breast biopsy. Pathologic examinations of sampled sonographically visible lesions revealed 39 cancers, 9 high‐risk lesions, 72 benign lesions, and 1 lesion not specified at surgery; 23% (9 of 128) of cancers were in the contralateral breast. Fifty‐four lesions were sonographically occult. Needle biopsy was performed for 93% (50 of 54) of occult lesions, revealing 8 cancers, 1 high‐risk lesion, and 41 benign lesions; 3 of the benign lesions did not have sufficient pathologic specimens but were benign at follow‐up. Magnetic resonance imaging guidance was used in 86% (43 of 50) of these biopsies. One contralateral cancer was identified in the sonographically occult subset. Of the 182 lesions that underwent second‐look sonography, 20% (36 of 182) had a change in management. Conclusions. Second‐look sonography has value in the evaluation of abnormalities found on breast MRI. We found enhancements in 70% (128 of 182), yielding 39 cancers.     

Noncardiogenic pulmonary edema caused by decompression sickness: rapid resolution following hyperbaric therapy

Noncardiogenic pulmonary edema is a recognized but uncommon manifestation of type 2 decompression sickness. It typically occurs within 6 hours of a dive. Because the adult respiratory distress syndrome in this setting is believed to be due to microbubbles in the pulmonary vasculature, recompression in a hyperbaric chamber has been recommended as a form of therapy. A patient developed noncardiogenic pulmonary edema following a seawater dive to 75 feet. There was complete radiologic and clinical resolution within 5 hours of hyperbaric therapy.     

Dural fistulas involving the cavernous sinus: results of treatment in 30 patients

Thirty symptomatic indirect carotid cavernous fistulas were treated between 1978 and 1986 with a variety of treatment modalities. Combined carotid artery and jugular vein compression resulted in a complete cure in seven of 23 patients (30%) and improvement in one additional patient. There were no complications from this treatment, which is performed by the patient on an outpatient basis. Patients in whom carotid jugular compression therapy failed or who demonstrated cortical venous drainage or visual decline were treated with intravascular embolization. Embolization resulted in complete cure in 17 of 22 (77%) and improvement in four of 22 (18%). One patient required surgical excision of the involved dura after embolization to achieve complete cure. There was one permanent complication (stroke), which resulted in mild weakness caused by clot formation on a catheter.     

Isolation and characterization of murine cell surface components. I. Purification of milligram quantities of Thy-1.1

The Thy-l.1 molecule was isolated from the BW5147 murine lymphoblastoid cell line. The initial step in purification was the preparation of a crude plasma membrane fraction followed by acetone precipitation. The acetone pellet was solubilized using deoxycholate (DOC) and Thy-1.1 was purified by use of a Lens culinaris lectin affinity column and an AcA-34 gel filtration column. The purified glycoprotein with Thy-1.1 activity had a mol wt of approximately 25,000 daltons. The isolation of this molecule was effected by detecting Thy-I activity utilizing rabbit anti- mouse brain serum tested on rat thymocytes. Congenic anti-Thy-l.1 serum was ineffective in detecting Thy-l.1 after DOC solubilization. An antiserum prepared in rabbits to the purified Thy-1.1 was found to be cytotoxic to mouse and rat thymocytes. The cytotoxic activity of this antisera could be completely absorbed with AKR/Jax brain and thymus but was not absorbed by liver. In addition, AKR/Jax thymocytes totally absorbed all cytotoxic activity of the rabbit anti-purified Thy-1 serum for BW5147 cells suggesting that the cell line shares identical specificities with normal thymocytes. The purified Thy-1.1 molecule was able to totally absorb the cytotoxic activity of mouse congenic anti-Thy-1. These studies serve as a model for the isolation of other murine lymphoid cell surface components in quantities for detailed structural and functional analysis.     

The Opportunity Loss of Boarding Admitted Patients in the Emergency Department

Objectives: Boarding admitted patients in emergency department (ED) treatment beds has been recognized as a major cause of ED crowding and ambulance diversions. When process delays impede the transfer of admitted patients from the ED to inpatient units, the department's capacity to accept new arrivals and to generate revenue from additional patient services is restricted. The objective of this study was to determine the amount of functional ED treatment capacity that was used to board inpatients during 12 months of operations at a community hospital and to estimate the value of that lost treatment capacity.
Methods: Historical data from 62,588 patient visits to the ED of a 450-bed nonprofit community teaching hospital in south central Pennsylvania between July 2004 and June 2005 were used to determine the amount of treatment bed occupancy lost to inpatient holding and the revenue potential of utilizing that blocked production capacity for additional patient visits.
Results: Transferring admitted patients from the ED to an inpatient unit within 120 minutes would have increased the functional treatment capacity of the ED by 10,397 hours during the 12 months of this study. By reducing admission process delays, the hospital could potentially have accommodated another 3,175 patient encounters in its existing treatment spaces. Providing emergency services to new patients in ED beds formerly used to board inpatients could have generated $3,960,264 in additional net revenue for the hospital.
Conclusions: Significantly higher operational revenues could be generated by reducing output delays that restrict optimal utilization of existing ED treatment capacity.