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E J DeMaria

Publications and source records attributed to E J DeMaria.

At least 37 records · Page 2Linked to original sources
PubMed1998

Lecithin protects against plasma membrane disruption by bile salts.

INTRODUCTION: Detergent disruption of epithelial plasma membranes by bile salts may contribute to pathogenesis of cholestasis and gastroesophageal reflux disease. Bile, despite containing high concentrations of bile salts, normally is not toxic to biliary or intestinal epithelia. We hypothesize that lecithin in bile may protect cell membranes from disruption by bile salts. METHODS: We studied the interactions of taurine conjugates of ursodeoxycholate (TUDCA), cholate (TCA), chenodeoxycholate (TCDCA), and deoxycholate (TDCA) with erythrocyte plasma membranes with or without large unilamellar egg lecithin vesicles for various times at 23 degreesC. Release of hemoglobin was quantified spectrophotometrically. The concentration of bile salt monomers and simple micelles in the intermixed micellar aqueous phase (IMMC) was determined by centrifugal ultrafiltration. RESULTS: The degree of hemolysis depended on the hydrophobicity of the bile salts and was progressive over time. Addition of lecithin reduced the hemolytic effects of 20 mM TCA or 2 mM TDCA in a concentration-dependent manner at both 30 min and 4 h. Increasing the concentration of lecithin progressively reduced the IMMC of TDCA. Hemolysis following addition of lecithin to 2 mM TDCA was comparable to hemolysis produced by lecithin-free TDCA solutions when diluted to similar IMMC values. CONCLUSION: We conclude that lecithin reduces plasma membrane disruption by hydrophobic bile salts. This protection may be attributable to association of bile salts with vesicles and mixed micelles, reducing the concentration of bile salt monomers and simple micelles available to interact with cell membranes. Lecithin may play a key role in preventing bile salt injury of biliary and gastrointestinal epithelia.

Bile Acids and Salts↗
PubMed1998

Laparoscopic hernia repair of an incisional hernia secondary to placement of an implantable cardioverter defibrillator.

We present the laparoscopic repair of a large incisional hernia secondary to placement of a subcostal ICD pulse generator. Laparoscopic repair of large incisional hernias provides a unique and technically feasible form of repair in the 2%-13% of patients who will develop an incisional hernia following an abdominal surgery. This form of hernia repair is associated with minimal morbidity and prompt resumption of patient activities and work.

Aged↗
PubMed1998

Adjustable laparoscopic gastric band for the treatment of morbid obesity: radiologic evaluation.

OBJECTIVE: This article describes the radiographic appearance of a recently developed laparoscopically placed adjustable gastric band for the treatment of morbid obesity. The optimal technique for contrast evaluation of the device, complications associated with its use, and the technique for stoma adjustments are also discussed. SUBJECTS AND METHODS: Between May and December 1996, 23 patients at our institution underwent laparoscopic placement of adjustable silicone gastric bands for treatment of morbid obesity. All patients underwent a barium upper gastrointestinal series before surgery, 1 day after band placement, at variable intervals when each patient returned for band adjustment, and at 1 year. RESULTS: Unlike the case in other gastric weight loss procedures, the optimal patient position for contrast evaluation of gastric bands was anteroposterior or slightly right posterior oblique. Twenty-one of 23 patients had no complications shown on the postoperative upper gastrointestinal series. Stoma size was approximately 3-8 mm, and most patients showed delayed esophageal emptying without obstruction. Two patients had herniation of the stomach through the gastric band with pouch enlargement, resulting in obstruction and the need for additional surgery. We saw no leaks or band erosions. Nineteen stoma adjustments were performed in 13 patients. One patient had an inverted port that could not be accessed for adjustment. CONCLUSION: As adjustable gastric bands become more widely used, radiologists need to be familiar with the radiographic appearance of the devices, the complications associated with their use, and the optimal patient positioning for contrast evaluation. Radiologists may also be involved with band adjustment to decrease or increase the stoma size and therefore need to understand the technique and potential difficulties of adjusting the stoma.

Adult↗
PubMed1997

Initial results of a prospective trial of outpatient laparoscopic cholecystectomy.

BACKGROUND: Whether or not laparoscopic cholecystectomy may be performed safely as an outpatient procedure is controversial. In 1993, a protocol for outpatient laparoscopic cholecystectomy was instituted to determine the benefits and safety of discharging patients within several hours of surgery. METHODS: The initial 60 outpatient laparoscopic cholecystectomies performed by one surgeon in a hospital-based outpatient teaching facility between February 1993 to June 1996 were prospectively studied. RESULTS: Fifty-eight (97%) patients were discharged successfully after an average stay in the recovery room of 3 h. There were no deaths. Two patients required overnight observation and three patients required readmission. Two patients (3%) had cystic duct leak. The average hospital stay for all patients undergoing laparoscopic cholecystectomy at the institution (inpatient and outpatient) decreased from 3.2 to 1.5 days and the average hospital cost decreased from $7,800 to $4,600 during this period. CONCLUSION: Laparoscopic cholecystectomy in an outpatient setting is safe and cost-effective in healthy patients.

Adult↗
PubMed1997

Increased intra-abdominal pressure and cardiac filling pressures in obesity-associated pseudotumor cerebri.

OBJECTIVES: To determine whether intra-abdominal pressure (as estimated from urinary bladder pressure) is elevated in patients with central obesity (as measured by sagittal abdominal diameter) and pseudotumor cerebri and whether this increased intra-abdominal pressure is associated with increased pleural pressure and cardiac filling pressure, implying a resistance to venous return from the brain. DESIGN: Nonrandomized, prospective. SETTING: University hospital, operating room. MAIN OUTCOME MEASUREMENTS: Intracranial pressure, urinary bladder pressure, sagittal abdominal diameter, transesophageal pleural pressure, central venous pressure, pulmonary artery pressure, and pulmonary artery occlusion pressure. SUBJECTS: Six women with pseudotumor cerebri (one with CSF leak, one with lumboperitoneal shunt). RESULTS: Urinary bladder pressure (22 +/- 3 cm H2O) and sagittal abdominal diameter (29 +/- 3 cm) were significantly elevated in these patients with elevated intracranial pressure (293 +/- 80 mm H2O) compared with a previously reported group of nonobese control patients. The transesophageal pleural pressure (15 +/- 10 mm Hg), central venous pressure (20 +/- 6 mm Hg), mean pulmonary artery pressure (31 +/- 6 mm Hg), and pulmonary artery occlusion pressure (21 +/- 7 mm Hg) were all markedly elevated compared with published normal values and with previous data from obese patients without pseudotumor cerebri. CONCLUSIONS: These data support the hypothesis that central obesity raises intra-abdominal pressure, which increases pleural pressure and cardiac filling pressure, which impede venous return from the brain, leading to increased intracranial venous pressure and increased intracranial pressure associated with pseudotumor cerebri.

Abdomen↗
PubMed1997

Laparoscopic Nissen fundoplication for severe gastroesophageal reflux disease: pros and cons.

The advent of the laparoscopic approach to Nissen fundoplication has led to a resurgence in enthusiasm for the surgical treatment of gastroesophageal reflux disease (GERD). However, controversy exists as to which subgroups of GERD patients are best treated surgically. The relative success of treatment with medical and surgical intervention in terms of both symptom control and objective resolution of esophageal injury must be weighed against the relative costs of each therapeutic strategy in both the short and long term, given that GERD tends to be a lifelong disorder. The following is the transcribed text of a debate held at the Medical College of Virginia as part of a continuing medical education program in which the statement "Laparoscopic antireflux surgery is superior to medical treatment for severe gastroesophageal reflux disease" was contested. Representatives from the departments of surgery and gastroenterology provided arguments supporting their respective sides of this issue. The purpose was not to promote polarization in treatment selection, but to review the available data in a forum that could promote development of a rational algorithm for clinical decision-making in patients with GERD who might benefit from antireflux surgery. Final comments from the authors are provided in an attempt to synthesize the arguments into a reasonable strategy for individual case management.

Decision Making↗
PubMed1996

Conversion of failed or complicated vertical banded gastroplasty to gastric bypass in morbid obesity.

BACKGROUND: Previous studies have documented a significantly better we weight loss for gastric bypass (GBP) than for vertical banded gastroplasty (VGB). Additional problems associated with VBG include intractable vomiting or gastroesophageal (GE) reflux, intragastric migration of the polypropylene band, staple line disruption, or inadequate weight loss due to excessive ingestion of high-calorie liquid or soft carbohydrates. PATIENTS AND METHODS: Fifty-eight morbidly obese patients underwent conversion from VBG to GBP for either weight-loss failure (15) or complications of VBG (43), including 2 who where referred with anastomotic leaks and peritonitis, 3 with band erosion, 15 with staple line disruption, and 23 with stomal stenosis, of whom 6 had severe GE reflux, with a Barrett's esophagus in 1. RESULTS: Percentage of excess weight loss in the 53 patients followed up for at least 1 year after conversion increased from 36% +/- 24% to 67% +/- 18%, and in the 15 "sweets eaters" from 20% +/- 19% to 70% +/- 19% (both P <0.001), was equal to weight loss after primary GBP, and was reasonably constant over 8 years in those patients who could be contacted for follow-up, although average follow-up after 5 years was only 45% All patients had resolution of GE reflux symptoms immediately after surgery and for at least 1 year or at last contact. Complications of conversion included 2 anastomotic leaks with major wound infections (1 in a referred patient requiring emergency subtotal gastrectomy following a VBG leak), 3 staple line disruptions (2 subclinical), 3 small-bowel obstructions, and 20 marginal ulcers or stomal stenoses (all responded to endoscopic balloon dilation or acid reduction therapy). Hemoglobin, calcium, and vitamin B12 levels remained within normal levels with prophylactic supplementation in patients who returned for follow-up evaluation. CONCLUSIONS: These data support the efficacy of conversion to GBP in morbidly obese patients with a failed or complicated VBG.

Gastric Bypass↗
PubMed1996

Greater risk of incisional hernia with morbidly obese than steroid-dependent patients and low recurrence with prefascial polypropylene mesh.

BACKGROUND: Incisional hernia is a serious complication of abdominal surgery. We compared incisional hernia frequency following gastric bypass (GBP) for morbid obesity versus total abdominal colectomy and ileal pouch-anal anastomosis (IPAA) for ulcerative colitis. A prefascial polypropylene mesh repair was also evaluated. PATIENTS AND METHODS: All patients had midline incisions, xiphoid to umbilicus in GBP patients and midepigastrium to pubis in IPAA patients. Fascia were closed with running No. 2 polyglycolic acid suture. Ninety-eight patients underwent prefascial polypropylene mesh repair; 80 were GBP patients, 46 had 1 previous repair, and 17 had 2 to 9 previous repairs (6 with properitoneal mesh). RESULTS: Incisional hernia occurred in 20% (198/968) of GBP patients (19% without versus 41% with a previous hernia, P < 0.001) versus 4% (7/171) of the IPAA patients (P < 0.001), of whom 102 (60%) were taking prednisone (32 +/- 2 mg/d) and 5 were quite obese (body mass index > or = 30 kg/m2). Additional risk factors for hernia in GBP patients included wound infection, diabetes, sleep apnea, and obesity hypoventilation. For the 98 patients who underwent prefascial polypropylene mesh repair, the mean follow-up was 20 +/- 2 months (range 6 to 104), and complications occurred in 35% of patients, including minor wound infection (12%), major wound infection (5%), seroma (5%), hematoma (3%), chronic pain (6%), and recurrent hernia (4%). CONCLUSIONS: Severe obesity is a greater risk factor for incisional hernia and hernia recurrence than chronic steroid use in nonobese colitis patients. A prefascial polypropylene mesh repair minimizes recurrence.

Abdomen↗
PubMed1996

Surgically placed gastro-jejunostomy tubes have fewer complications compared to feeding jejunostomy tubes.

OBJECTIVE: During laparotomy, jejunostomy tubes (J tubes) are often placed to provide access for enteral nutrition in the immediate postoperative period. However, the placement of such tubes may be associated with potentially devastating intra-abdominal complications possibly related to the tenuous security of a tube through the small bowel wall. An alternative method for enteral nutrition access is to surgically place a "PEG-J" tube (i.e., surgical G/J tube) thus providing for jejunal feedings via a gastrotomy without a jejunotomy. The purpose of this study is to assess whether surgically placed G/J tubes reduce the postoperative complications in comparison to feeding J tubes. METHODS: Over the past 18 months, 92 J tubes and 56 G/J tubes were placed during laparotomy at a single institution and the method chosen by surgeons' preference. The frequency of complications associated with each tube was determined by review of the postoperative medical records. RESULTS: There was no enteric leakage in those patient given G/J tubes (p < 0.05). Furthermore 10% of the patients receiving J tubes required operative repair of a J tube complication while no patient with an access complication following G/J tube placement required surgical repair (p < 0.05). CONCLUSIONS: These results demonstrate that operative positioning of a jejunal feeding tube through a gastrostomy tube (surgical G/J tube) provides a safer route for enteral nutrition than does direct tube placement via the jejunal wall, by significantly reducing both the incidence of enteric leakage and the requirement for operative repair.

Adult↗
PubMed1996

Lactic acidosis during sepsis is related to increased pyruvate production, not deficits in tissue oxygen availability.

OBJECTIVE: The purpose of this study was to quantitate the derangements in intermediary carbohydrate metabolism and oxygen use in severely septic patients in comparison with healthy volunteers. SUMMARY BACKGROUND DATA: It commonly has been assumed that the development of lactic acidosis during sepsis results from a deficit in tissue oxygen availability. Dichloroacetate (DCA), which is known to increase pyruvate oxidation but only when tissue oxygen is available, provides a means to assess the role of hypoxia in lactate production. METHODS: Stable isotope tracer methodology and indirect calorimetry was used to determine the rates of intermediary carbohydrate metabolism and oxygen use in five severely septic patients with lactic acidosis and six healthy volunteers before and after administration of DCA. RESULTS: Oxygen consumption and the rates of glucose and pyruvate production and oxidation were substantially greater (p < 0.05) in the septic patient compared with healthy volunteers. Administration of DCA resulted in a further increase in oxygen consumption and the percentage of glucose and pyruvate directed toward oxidation. Dichloroacetate also decreased glucose and pyruvate production, with a corresponding decrease in plasma lactate concentration. CONCLUSIONS: These findings clearly indicate that the accumulation of lactate during sepsis is not the result of limitations in tissue oxygenation, but is a sequelae to the markedly increased rate of pyruvate production. Furthermore, the substantially higher rate of pyruvate oxidation in the septic patients refutes the notion of a sepsis-induced impairment in pyruvate dehydrogenase activity.

Acidosis, Lactic↗
PubMed1995

Except for alanine, muscle protein catabolism is not influenced by alterations in glucose metabolism during sepsis.

OBJECTIVE: To assess any relationship between hyperglycemia and muscle protein catabolism associated with critical illness. DESIGN: Cohort analytic study. SETTING: Clinical research center and intensive care unit of a university hospital. PARTICIPANTS: Six healthy volunteers and five patients with severe sepsis. INTERVENTIONS: Study subjects were given infusions of 6,6,d2 glucose and 15N lysine for 6 hours. After infusion of the stable isotopes for 2 hours (basal period), dichloroacetate, which accelerates pyruvate oxidation, was given (dichloroacetate period). Leg blood flow was measured by indocyanine green dye dilution, and femoral artery and vein substrate concentrations were quantitated. MAIN OUTCOME MEASURES: The metabolic rates of glucose production, oxidation, and clearance; the whole-body protein breakdown rate; and the net efflux of amino acids from the leg were determined. RESULTS: In comparison with the healthy volunteers, septic patients had significant elevations in glucose production, oxidation, and clearance, accelerated protein catabolism, and greater net peripheral efflux of amino acids. Dichloroacetate significantly decreased glucose production and increased the percentage of glucose directed toward oxidation in both healthy volunteers and septic patients. However, this dichloroacetate-induced perturbation of glucose utilization had no significant effect on whole-body protein breakdown or the efflux of specific amino acids from the leg except for alanine, whose net efflux doubled (P < or = .05). CONCLUSIONS: The findings of this study demonstrate a universal acceleration in the metabolic rates of both intermediary glucose metabolism and protein/amino acid catabolism during sepsis. Except for alanine, however, there appears to be no coupling between these two physiologic responses to sepsis.

Adult↗
PubMed1995

Laparoscopic bilateral inguinal hernia repair under local anesthesia.

A case report of the laparoscopic repair of bilateral inguinal hernias performed under local anesthesia with intravenous sedation is presented. The combination of nitrous oxide for peritoneal insufflation and an ultrasonically activated scalpel for dissection made the procedure feasible. It is hoped that this technique can extend laparoscopic surgery to patients who are poor candidates for general anesthesia.

Anesthesia, Local↗
PubMed1995

Decreased splanchnic perfusion measured by duplex ultrasound in humans undergoing small volume hemorrhage.

OBJECTIVES: To quantitate duplex Doppler measurements of splanchnic perfusion to determine if these measurements are reproducible in euvolemic humans and if such measurements are sensitive to mild degrees of systemic hypovolemia. DESIGN: Prospective, nonrandomized, controlled trial. SETTING: Clinical research center. PARTICIPANTS: Seven fasting, healthy male and female volunteers, ranging in age from 25 to 37 yrs and weighing 60 to 90 kg. INTERVENTIONS: Pulse, blood pressure, hematocrit, and duplex Doppler measurements of the peak systolic velocity and time averaged velocity of the subdiaphragmatic aorta, celiac artery, and superior mesenteric artery were obtained at four time points. Time points I and II were on separate days before hemorrhage and consisted of routine blood donation of 450 mL. Time point III was immediately after blood donation. Time point IV was 24 hrs after donation. Estimated blood flow was calculated from time averaged velocity (estimated blood flow = 60[vessel cross-sectional area][time averaged velocity]). MEASUREMENTS AND MAIN RESULTS: Vital signs and hematocrit remained without significant change at all time points. Peak systolic velocity, time averaged velocity, and estimated blood flow were also unchanged between measurements at time points I and II. However, after a mean reduction of 9.1% of total blood volume, duplex ultrasound detected significant decreases of 14.5% in celiac artery and superior mesenteric artery peak systolic velocity, as well as 15.1%, 17.3%, and 20.2% decreases in aorta, celiac artery and superior mesenteric artery time averaged velocity and estimated blood flow, respectively (all values p < .05 vs. baseline, Duncan's multiple range test). All measured variables returned to baseline 24 hrs after hemorrhage. CONCLUSIONS: Noninvasive duplex Doppler measurements of splanchnic peak systolic velocity, time averaged velocity, and estimated blood flow are reproducible and sensitive to small changes in intravascular volume. These data suggest a potential clinical role for duplex imaging in the treatment of critically ill patients to guide therapy to optimize splanchnic perfusion.

Adult↗
PubMed1995

Treatment of increasing intracranial pressure secondary to the acute abdominal compartment syndrome in a patient with combined abdominal and head trauma.

Acute abdominal compartment syndrome has recently been shown to raise intracranial pressure (ICP). This may increase the risk of ischemic neuronal damage by decreasing cerebral perfusion pressure. We report the successful management of a patient with severe multisystem injury in whom abdominal decompression dramatically reduced high ICP unresponsive to medical measures.

Abdomen↗
PubMed1994

Decreased lactate in endotoxin-resistant mice undergoing hemorrhage is independent of tumor necrosis factor availability.

Although C3H/HeJ mice, characterized by a genetic deficiency in macrophage cytokine release in response to endotoxin, have been studied extensively to gain insight into the possible role of various cytokines in sepsis, few past studies have examined the physiologic response to hemorrhagic shock in this "endotoxin-resistant" strain. We utilized a fixed-volume model of hemorrhagic shock and two different levels of hemorrhage severity (50 and 67% blood volume) to compare C3H/HeJ mice to normal C3H/HeN mice. An additional group of endotoxin-sensitive C3H/HeN mice were treated with 2.5 mg/kg of anti-tumor necrosis factor (TNF) antibody to define the possible role of TNF in shock physiology. Hematocrit, circulating neutrophils, and plasma glucose and lactate concentrations were measured following hemorrhage. TNF increased significantly following hemorrhage in normal mice but did not increase in C3H/HeJ mice or in C3H/HeN mice treated with anti-TNF antibody. No difference between groups was identified in hematocrit, circulating neutrophils, or glucose. Whereas plasma lactate increased significantly by 30 min in all groups, lactate returned to baseline levels in C3H/HeJ mice at 60 min, but remained persistently elevated in C3H/HeN mice and in C3H/HeN mice treated with anti-TNF antibody. The data demonstrate attenuated lactate accumulation in C3H/HeJ mice following hemorrhage. Inhibition of circulating TNF activity with anti-TNF antibody failed to reproduce this late decrease in plasma lactate in normal mice. The data suggest that macrophage products other than TNF known to be deficient in C3H/HeJ mice contribute to anaerobic metabolism in hemorrhagic shock.

Animals↗
PubMed1994

The role of inflammatory cytokines in wound healing: accelerated healing in endotoxin-resistant mice.

UNLABELLED: The role of cytokines in normal wound healing remains poorly defined. In vitro, tumor necrosis factor alpha (TNF-alpha) decreases collagen accumulation, perhaps by increasing collagenase activity. The current study was undertaken to test the hypothesis that cytokines impair wound healing and collagen production. Wounds in C3H/HeJ (J) mice, which are characterized by a genetic defect in macrophage production of TNF and other cytokines in response to endotoxin, were compared with wounds in normal endotoxin-sensitive C3H/HeN (N) mice. METHODS: TNF (by murine ELISA) and collagenolytic activity (CA by in vivo labelled collagen fibril degradation assay) were measured in wound fluid from silicone reservoirs on post-wounding days 1, 3, and 5 (n = 5 per group). Hydroxyproline (HOP, nmol/mg sponge) incorporation (by HPLC) in polyvinylacohol sponges and breaking strength (BS, as determined by tensiometry) in linear wounds were assessed on days 5, 7, 10, and 14 (n = 5 per group). The data demonstrate significantly increased BS at 5 and 7 days in endotoxin-resistant J mice compared with that in endotoxin-sensitive N mice. An early, significant reduction in TNF production in J mice corresponded with a significant increase in CA on day 1, increased collagen production at day 7, and increased procollagen gene transcription at early time points. Conclusion. The reduced production of inflammatory cytokines including TNF in the wound fluid of J mice corresponded with an early improvement in wound tensile strength. An accelerated accumulation of collagen in the wounds of J mice, perhaps resulting from a significant decrease in collagenolytic activity or increased collagen production, are potential mechanisms. The data suggest that cytokines produced in normal healing of clean wounds may contribute to a delay in increased tensile strength.

Animals↗
PubMed1993

Hemorrhagic shock in endotoxin-resistant mice: improved survival unrelated to deficient production of tumor necrosis factor.

Although tumor necrosis factor (TNF) has been implicated in sepsis-induced mortality, its role in the pathophysiology of hemorrhagic shock (HS) remains ill defined. We studied three groups of acutely anesthetized mice undergoing HS to determine the role of TNF in HS mortality. Shock was initiated in each group after heparinization by arterial bleeding of 4 mL/100 g body weight followed by 12 mL/100 g body weight resuscitation with normal saline at 1 hour. The C3H/HeJ mice (n = 14), characterized by a genetic defect in macrophage production of TNF and other cytokines in response to endotoxin, were compared with the closely related C3H/HeN strain (n = 18), which do produce TNF. A second group of C3H/HeN mice were passively immunized to TNF by pretreatment with 2.5 mg/kg anti-murine TNF antibody (Ab) before HS. In contrast to the high TNF levels measured following HS in C3H/HeN controls, post-HS TNF was undetectable in C3H/HeJ mice. Five-day survival rate and survival time were significantly greater in C3H/HeJ mice when compared with C3H/HeN controls. Anti-TNF Ab pretreatment of C3H/HeN mice abolished the increase in TNF but did not improve survival. The data demonstrate a striking improvement in survival of TNF-deficient C3H/HeJ mice following severe HS. However, the improved survival does not appear to result from deficient TNF production, since Ab pretreatment did not decrease HS mortality. The improved survival in C3H/HeJ mice suggests that cytokines other than TNF may play a role in the pathophysiology of HS.

Animals↗