Khursheed N. Jeejeebhoy

Quality of life, nutritional status, and gastrointestinal hormone profile following the Whipple procedure.

Pancreatic cancer is the second commonest gastrointestinal cancer, after colorectal cancer, in Canada, and most other European and North American countries. Unfortunately, most patients present with advanced locoregional or metastatic disease. For the 10-20% of patients who have localized disease, pancreatic resection is generally the preferred treatment option. Because pancreaticoduodenectomy can be performed safely in expert hands, it has become a more accepted procedure for patients with pancreatic cancer. Furthermore, it has also meant that there is increasing scrutiny of the longterm outcome of patients, especially their nutritional status and quality of life. In a study of 25 unselected patients who had a Whipple procedure at least 6 months previously and were not known to have residual or recurrent disease, patients appeared to have few gastrointestinal symptoms compared to control patients. However, none of the subjects appeared to be clinically malnourished. Dietary intake and lean body mass were comparable to that of the control group. Quality of life was excellent in these patients. The mean utilities were 0.98 and 1.0 suggesting near normal wellbeing. Similarly, results using the SIP and GIQLI suggested no/minimal impairment in general wellbeing and gastrointestinal function. Two other studies suggest that median survival and performance status are improved in patients having a resection, but it may be due to their disease being more favorable rather than the treatment being beneficial. Further studies objectively assessing the quality of life of all patients undergoing treatment for pancreatic cancer at the various disease stages are required.

Nutritional absorption in short bowel syndrome

Eight patients with a short bowel resulting from intestinal resection and clinically stable for at least one year were studied for 10 days. The diet chosen was lactose-free with a low fiber content and contained 22% of total calories as protein, 32% as carbohydrate, and 46% as fat. Total fluid volume was kept constant, and all patients were in positive nitrogen balance. During the 10-day period, blood chemical concentrations, stool, and/or ostomy volume, urine volume, electrolyte excretion, and calorie and divalent cation absorption were measured. In addition it was determined that fluid restriction during meals did not affect these parameters. In these patients the absorptions of fat, carbohydrate, protein, and total calories were 54%, 61%, 81%, and 62%, respectively. Similarly the absorption of the divalent cations, calcium, magnesium, and zinc, were 32%, 34%, and 15%, respectively. We suggest that patients with short bowel syndrome, who have been stable for at least one year and who can tolerate oral diets, do not need to restrict fat or to separate fluids from solids during their meals. Furthermore, they should increase their oral intake to 35–40 kcal/kg ideal body weight in order to counteract their increased losses. The diet should contain 80–100 g protein/day in order to maintain a positive nitrogen balance and a large margin of safety. In addition, these patients may take oral supplementation of calcium, magnesium, and zinc to maintain divalent cation balance.

Control of gastric pH with cimetidine: Boluses versus primed infusions

Previous studies suggest that antacids are more effective than intravenous cimetidine in maintaining the gastric pH above 4.0 in acutely ill patients. We hypothesized that this was because blood levels of cimetidine are not sustained at therapeutic levels with the bolus doses. The purpose of this study was to compare gastric pH and serum cimetidine levels when cimetidine was administered as bolus versus infusion. We studied 23 acutely ill patients who received intravenous cimetidine given as boluses and primed infusions. The gastric pH could be maintained above 4.0 with infusions of up to 50 mg/h (1200 mg/day) in 20 patients, compared with only 5 patients with bolus administrations of up to 300 mg every 6 h (1200 mg/day). The differences in ability to maintain the gastric pH above 4.0 were entirely due to the reduced ability of bolus infusion to maintain an adequate serum level. Neither technique could maintain the pH above 4.0 in 3 patients, all of whom had received cimetidine recently. A gastric pH greater than 4.0 correlated directly with a therapeutic serum cimetidine level. We conclude that infusions of cimetidine are better able to sustain therapeutic blood levels and, therefore, are superior to bolus cimetidine in maintaining gastric pH above 4.0. Some patients, however, may not respond to cimetidine even if therapeutic levels are achieved and may require supplemental antacids.

Psychological factors in irritable bowel syndrome.

This paper describes the prevalence and incidence of psychiatric disorders in IBS patients using a standardized psychiatric interview, and proposes a psychological model for investigating one aspect of IBS. Forty-four IBS patients and 28 nonclinical participants received a psychiatric interview (Diagnostic Interview Schedule) and completed the Lie Scale of the Eysenck Personality Inventory (L-EPI). Results indicated that a significant percentage (59%) of the IBS group met DSM-III criteria for a psychiatric disorder within the last year, far more than occurred in the matched nonclinical comparison group. Relative to the comparison group, the IBS group also had significantly higher lie scores on the EPI indicating a response style of social desirability. On the basis of these findings, together with earlier work by Latimers group, a conceptual model was formulated on the notion that some IBS patients may have a self-schema (i.e. knowledge of self, stored in memory) characterized by social desirability. We suggest that the construct of self-schema may be helpful in differentiating IBS from psychiatric groups both conceptually and therapeutically.

A controlled trial of the effect of parenteral nutritional support on patients with respiratory failure and sepsis.

Energy and protein metabolism was studied in 11 septic patients receiving ventilatory support while on three different intravenous regimens. They received 5% dextrose in water (D5W), and one of two different regimens of parenteral nutritional support (PNS); either amino acid and dextrose (PNA) or amino acid and dextrose and lipid (PNB). All patients were given D5W and PNS in random order. The energy intake was targetted to exceed by 50% the measured metabolic rate. On D5W the mean measured energy expenditure was only 15.2% above the expected energy expenditure (p<0.02). A respiratory quotient of 0.75 while on D5W showed that in the absence of PNS the major part of energy requirements came from fat oxidation. In addition, on D5W these patients were in negative nitrogen and protein (synthesis-catabolism) balance. With PNS the metabolic rate rose significantly (p<0.02). While on PNA, the CO2 production was significantly higher than with PNB, and despite receiving all non-protein energy as glucose, the patients continued to oxidise fat to meet about 30% of their energy requirements. Continued fat oxidation was found to be associated with insulin resistance and high catecholamine levels, suggesting a cause and effect relationship. PNS caused an increase in protein (synthesis - catabolism) and nitrogen balances, and reduced leucine oxidation. The fall in leucine oxidation was greater on PNB than on PNA. Protein and nitrogen balances, expressed per gram of amino acid infused, were significantly better with PNB than PNA. It was concluded that insulin resistance may make fat an efficient source of energy.

Lipid-associated total parenteral nutrition in patients with severe acute pancreatitis

Biochemical data were studied in 18 patients with severe acute pancreatitis receiving lipid associated with total parenteral nutrition. The mean nonprotein energy intake was 30 kcal/kg/day, with 34-70% of the nonprotein calories as lipid. These parameters were no different between patients who survived and those who died. The mean sum of Ranson criteria was significantly higher in patients who died as compared with those who survived. Plasma triglycerides, glucose, albumin, and the amount of insulin supplementation were related to the severity of the disease and to the outcome. Persistent hypertriglyceridemia, hyperglycemia, hypoalbuminemia, and higher insulin requirements were observed in patients who died in comparison with those who survived and this appeared to be an index of fatal outcome. These abnormalities reflect in part an inability to utilize nonprotein energy, because the measured energy expenditure in relation to intake was lower in the patients who died, despite comparable intakes and expected energy expenditures.

Assessment of Nutritional Status in the Oncologic Patient

The term malnutrition is a continuum that progresses from only a disequilibrium of intake in relation to needs, to gross structural and functional changes. Furthermore, these changes may be mutually exclusive. How then do we define malnutrition? Strictly, malnutrition starts, as we have shown, when the patient fails to eat enough to meet needs and progresses through a series of functional changes that precede any changes in body composition. These functional changes are related to the duration of reduced intake and its severity. Finally, body wasting occurs, and biochemical indices become abnormal. To base the definition of malnutrition on any one of these changes is inappropriate. Thus, a patients nutritional status should be defined by the following criteria: nutrient intake in relation to needs; associated changes in organ function; associated changes in body composition; and associated changes in biochemistry. Only by recognizing the different facets of malnutrition can we define its various manifestations in relation to our clinical objectives. In attempting to achieve this goal, we have found muscle function tests a most useful and objective investigational tool.

Trace Elements in Total Parenteral Nutrition

Cotzias (1) defined an essential trace element as one which has the following characteristics: n n(1) n nPresent in healthy tissues of all living things. n n n n n(2) n nConstant tissue concentration from one animal to the next. n n n n n(3) n nWithdrawal leads to a reproducible functional and/or structural abnormality. n n n n n(4) n nAddition of the element prevents the abnormality. n n n n n(5) n nThe abnormality is associated with a specific biochemical change. n n n n n(6) n nThe biochemical change is prevented and/or cured along with the observed clinical abnormality.