George F. Sheldon

The effect of parenteral nutrition on gastrointestinal immunity. The importance of enteral stimulation.

Secretory IgA (S-IgA), an immunoglobulin present in secretions, prevents the adherence of bacteria to mucosal cells and is the principle component of the gut mucosal defense system. The purpose of this study was to determine whether the route of nutrient administration affects S-IgA. Twenty-five female Fisher rats were randomized into three groups. Groups I and II were fed an isonitrogenous, isocaloric standard hyperalimentation solution, Group I intravenously and Group II via a gastrostomy. Group III (control) was fed rat chow and water ad lib. Since bile is one of the principle sources of S-IgA, animals had biliary T-tubes placed for sampling of bile every 4 days. At day 16, Group I animals were fed rat chow and water for an additional 8 days. S-IgA was measured by the ELISA immunoassay. Results indicated at day 16 that the S-IgA level in mg/ml of Group I was 1.1 +/- 0.2, while the S-IgA in Groups II and III was 2.2 +/- 0.6 and 2.2 +/- 0.26, respectively. Furthermore, the S-IgA level in Group I after 8 days of enteral feeding rose to 1.8 +/- 0.4. The difference in S-IgA levels between enterally and parenterally fed rats suggests that an important defense barrier is compromised during parenteral hyperalimentation. Rats fed the same nutrients by gastrostomy maintained S-IgA levels better than rats fed the same nutrients intravenously. The rapid return to normal levels after resumption of enteral feeding suggests that the intraluminal presence of foodstuffs is essential for maintenance of S-IgA.

Management of foreign body ingestion.

Management of ingested foreign bodies (FB) is a common clinical problem. A 10-year experience of 101 foreign body ingestions is reported. The experience suggests that endoscopic removal of foreign bodies is curative for objects located in the crico-pharynx or upper esophagus. Foreign bodies which pa

Enteral and Parenteral Feeding Influences Mortality after Hemoglobin-E. coli Peritonitis in Normal Rats

Enteral feeding with 25% dextrose-4.25% Freamine II (TPN) improves the survival of malnourished animals to normal levels after hemoglobin-E. coli adjuvant peritonitis, whereas intravenous feeding does not. To determine whether intravenous feeding maintained a high survival rate in previously well-nourished animals, 81 rats received TPN via gastrostomy or intravenous infusion for 12 days. They were then fasted for 24 hours and given a septic challenge. Gastrostomy-fed animals survived the challenge significantly better than intravenously fed animals. Enteral feeding appears to be important in producing a high survival rate after hemoglobin-E. coli adjuvant peritonitis.

Women in Academic General Surgery

Purpose. To portray the professional experiences of men and women in academic general surgery with specific attention to factors associated with differing academic productivity and with leaving academia. Method. A 131-question survey was mailed to all female (1,076) and a random 2:1 sample of male (2,152) members of the American College of Surgeons in three mailings between September 1998 and March 1999. Detailed questions regarding academic rank, career aspirations, publication rate, grant funding, workload, harassment, income, marriage and parenthood were asked. A five-point Likert scale measured influences on career satisfaction. Responses from strictly academic and tenure-track surgeons were analyzed and interpreted by gender, age, and rank. Results. Overall, 317 surgeons in academic practice (168 men, 149 women) responded, of which 150 were in tenure-track positions (86 men, 64 women). Men and women differed in academic rank, tenure status, career aspirations, and income. Women surgeons had published a median of ten articles compared with 25 articles for men (p < .001). Marriage or parenthood did not influence numbers of publications for women. Overall career satisfaction was high, but women reported feeling career advancement opportunities were not equally available to them as to their male colleagues and feeling isolation from surgical peers. Ten percent to 20% of surgeons considered leaving academia, with women assistant professors (29%) contemplating this most commonly. Conclusion. Addressing the differences between men and women academic general surgeons is critical in fostering career development and in recruiting competitive candidates of both sexes to general surgery.

A statewide, population-based time-series analysis of the increasing frequency of nonoperative management of abdominal solid organ injury

IntroductionEmergency operative intervention has been one of the cornerstones of the care of the injured patient. Over the past several years, nonoperative management has increasingly been recommended for the care of selected blunt abdominal solid organ injuries. The purpose of this study was to utilize a large statewide, population-based data set to perform a time-series analysis of the practice of physicians caring for blunt solid organ injury of the abdomen. The study was designed to assess the changing frequency and the outcomes of operative and nonoperative treatments for blunt hepatic and splenic injuries. MethodsData were obtained from the state hospital discharge data base, which tracks information on all hospitalized patients from each of the 157 hospitals in the state of North Carolina. All trauma patients who had sustained injury to a solid abdominal organ (kidney, liver, or spleen) were selected for initial analysis. ResultsDuring the 5 years of the study, 210,256 trauma patients were admitted to the states hospitals (42,051 ± 7802 per year). The frequency of nonoperative interventions for hepatic and splenic injuries increased over the period studied. The frequency of nonoperative management of hepatic injuries increased from 55% in 1988 to 79% in 1992 in patients with hepatic injuries and from 34% to 46% in patients with splenic injuries. The rate of nonoperative management of hepatic injuries increased from 54% to 64% in nontrauma centers compared with an increase from 56% to 74% in trauma centers (p = 0.01). In patients with splenic injuries, the rate of nonoperative management increased from 35% to 44% in nontrauma centers compared with an increase from 33% to 49% in trauma centers (p < 0.05). The rate of nonoperative management was associated with the organ injury severity, ranging from 90% for minor injuries to 19%–40% for severe injuries. Finally, in an attempt to compare blood use in operatively and nonoperatively treated patients, the total charges for blood were compared in the two groups. When compared, based on organ injury severity, the total blood used, as measured by charges, was lower for nonoperatively treated patients.

An analysis of the association of trauma centers with per capita hospitalizations and death rates from injury.

ObjectiveThis study used population-based data bases to assess the association of trauma centers with per capita county hospitalization and trauma death rates in the State of North Carolina. Summary Background DataThe current study extended previous work using two North Carolina data bases to assess the association of the presence of a trauma center with per capita county trauma death rates. MethodsData on per capita county trauma hospitalizations and deaths were obtained from the state hospital discharge data base and the North Carolina Medical Examiners data base. Bivariate and multivariate analysis techniques were used. The dependent variables of interest were prehospital, hospital, and total trauma death rates and hospitalization rates for injury. ResultsBivariate analysis identified a number of factors associated with per capita county hospitalizations and trauma death rates. These included the per cent unemployment, racial distribution, county alcohol tax receipts, and advanced life support certified emergency medical services providers. The per capita trauma death rates were significantly lower in counties with trauma centers compared with those without trauma centers (4.0 ± 0.5 and 5.0 ± 1.1 deaths per 10,000 population, p = 0.0001, respectively). The per capita hospitalizations for trauma were also lower in counties with trauma centers. Multivariate modeling showed that the presence of a trauma center and advanced life support providers were the best predictors of decreased per capita county trauma death rates. ConclusionsThe study showed that the presence of a trauma center and advanced life support training were the two medical system factors that were the best predictors of the per capita county prehospital ‘and total trauma death rates. These findings are consistent with the hypothesis that trauma centers are associated with a decrease in trauma death rates.

Degloving injuries of the extremities and torso.

Degloving injuries of the extremities and torso occur with relative frequency and are associated with a high morbidity and mortality. The common aim of all surgical approaches is to reestablish skin coverage over the injured area, but therapies differ in both technique and results. This survey evaluates the management and results of 21 patients sustaining degloving injury of at least 2/3 the circumference of the torso or an extremity. Initial surgical techniques which employ application of the skin as a full- or split-thickness graft were contrasted with those in which salvage of the entire flap with its subcutaneous tissue was attempted. The results suggest that immediate use of the degloved skin as a full-or split-thickness skin graft gives the most satisfactory coverage to the denuded areas. Other important features in management include frequent observation and immobilization of the extremity postoperatively, and use of mesh grafts when necessary to cover large areas. Recent emphasis on the blood supply of the skin underscores the importance of its circulation as the determinant of flap survival. Daily observation until the flap becomes fixed is mandatory. Primary reattachment of the full-or split-thickness flap by suture or use of compression dressings without grafting is unsuccessful and should be abandoned as an acceptable approach to this problem.

Phosphate depletion and repletion: relation to parenteral nutrition and oxygen transport.

Phosphate depletion occurring during total parenteral nutrition has been frequently reported during the past 4 years. Hypophosphatemia may be associated with confusion, hyperventilation, and neuromuscular irritability, suggesting a total body phosphate deficiency. If inorganic phosphate levels fall below 1.0 mg %, diminished red cell glycolysis occurs with low erythrocyte levels of 2, 3 diphosphoglycerate and adenosine triphosphate. Lowered red cell organic phosphates are associated with increased hemoglobin oxygen affinity. If severe hypophosphatemia occurs, hemolytic anemia, which is correctible by phosphate infusion, may result. In addition, leucocyte function is impaired by low levels of serum inorganic phosphate. While recognized as a needed additive, recommended phosphate supplements vary. Different infusion regimens have been suggested over the past 4 years, based primarily on assumed daily requirements. In the 19 trauma patients described who received hyperalimentation as part of their treatment, phosphate administration was calculated retrospectively and prospectively as a function of non-protein calories infused. Four different groups were studied. Group A received no phosphate additive and quickly became severely hypophosphatemic. Group B received from one to 15 meg of potassium acid phosphate per 1,000 K cal and developed a more gradual lowering of serum inorganic phosphate levels. Group C received 15 to 25 meg of potassium acid phosphate per 1,000 K cal and maintained normal phosphate levels throughout the course of treatment. Group D received greater than 25 meg of potassium acid phosphate per 1,000 K cal and gradually increased their serum inorganic phosphate levels. A significant positive correlation was found between serum inorganic phosphate levels, 2, 3 diphosphoglycerate levels, adenosine triphosphate levels, and P50 of the oxy-hemoglobin dissociation curve. No patients developed hemolytic or neuromuscular syndromes which were attributable to hypophosphatemia. This study describes a simple method for the maintenance of adequate phosphate levels in patients whose dextrose-protein solutions may vary from day to day, by relating it to non-protein calories. Provision of 20 to 25 meg of potassium dihydrogen phosphate per 1,000 K cal will maintain normal serum levels of inorganic phosphate during total parenteral nutrition.

Abgs and Arterial Lines: The Relationship to Unnecessarily Drawn Arterial Blood Gas Samples

Arterial blood gas measurements (ABGs) are the most common tests ordered in an ICU. ABG utilization in a surgical ICU over a 1-year period (September 1, 1987-October 31, 1988) was evaluated to identify factors that might help reduce overutilization. A total of 842 admissions comprising 2,381 patient days were reviewed. ABGs were the most commonly ordered test (mean of 4.8/patient/day). Patients with arterial lines (A-lines) had more ABGs drawn than those who did not regardless of the value of PaO2 (p less than 0.01), PaCO2 (p less than 0.01 except for PaCO2 greater than 55), APACHE II score (p less than 0.01), use of ventilators (p less than 0.01), pulse oximeters (p less than 0.01), or a combination of the last two (p less than 0.01). Multivariate analysis demonstrated that the presence of an A-line was the most powerful predictor of the number of ABGs drawn per patient (p less than 0.0001) independent of all other measures of the patients clinical status such as the use of ventilators, oximeters, and values of PaO2, PaCO2, or the APACHE II score. This suggests that ABGs are being drawn unnecessarily simply because of the presence of an A-line. To reduce the number of ABGs drawn, a policy for specific indications for placement of A-lines and ABG analysis should be adopted.

Duodenal trauma: experience of a trauma center.

In the past decade 93 patients with duodenal injury were treated at a trauma center. By chart review, the age, sex, mechanism of injury, time to initial exploration (and the reason for delay), laboratory results, associated injury, extent of duodenal injury, operative repair, use of drains and tube decompression, morbidity, and cause of death were tabulated in order to improve management of these injuries. Of 87 patients surviving until the time of operative repair 73% required no repair (four) or primary closure (59). The remainder had either resection with primary anastomosis (ten), diverticulization (12), or pancreaticoduodenectomy (two). All patients with penetrating trauma were immediately explored. Patients with blunt trauma were explored on the basis of the judgment of house staff and faculty. Overall mortality was 18%. Significant morbidity occurred in 49% of survivors. This urban experience was heavily weighted toward penetrating injury. In this group early death usually resulted from associated vascular injuries. Blunt duodenal injury was less frequently associated with immediate exsanguination. Mortality associated with blunt duodenal injury was usually the result of delayed diagnosis. In blunt duodenal trauma peritoneal lavage is not diagnostic and may often be misleading; in this series 50% of lavages were false negatives. Blunt duodenal trauma, particularly when combined with pancreatic injury or delayed repair, was a lethal combination. A high index of suspicion and aggressive diagnostic evaluation (CT contrast study/amylase) in the emergency department is required in equivocal cases to avoid morbidity and mortality.