Donald R. Duerksen

Peripherally inserted central catheters for parenteral nutrition: a comparison with centrally inserted catheters.

BACKGROUND Central venous access is crucial for the provision of adequate parenteral nutrition (PN). The type of central venous access device (CVAD) has evolved over the past 10 years. The most recent trend has been to use peripherally inserted central catheters (PICCs). This development has occurred without controlled clinical trials. METHODS Over a 10-year period, the nutrition support service at a single institution has prospectively collected data on CVADs used for providing PN. The types of CVAD used for providing PN were analyzed, and the major complications associated with CVADs, thrombosis and line sepsis, were compared over three different time periods: 1988-1989; 1992-1993; 1996-1997. In addition, complications associated with PICCs were compared with other CVADs. RESULTS The following were the dominant CVADs over each of the three time periods: 1988-1989: tunneled catheters, 80%; 1992-1993: nontunneled catheters, 46%; and 1996-1997: PICCs, 48%. There was a decreased incidence of sepsis and pneumothorax in 1996-1997 and an increase in severed or leaking catheters and phlebitis. In a comparison of PICC and non-PICC catheters over the past 3 years, there was a trend toward decreasing sepsis with PICC catheters but an increase in malposition, inadvertent removal, and severed or leaking catheters. CONCLUSIONS PICCs have replaced tunneled and nontunneled central catheters as the most commonly used CVAD for providing PN. PICCs do not result in increased line sepsis or thrombosis but have an increased incidence of local complications such as leaking catheters, phlebitis, and malposition.

An evaluation of resting energy expenditure in hospitalized, severely underweight patients

A prospective trial was conducted with 14 hospitalized patients who were severely underweight with a mean weight of 40.9+/-5.1 kg and 70.7+/-7.8% of ideal body weight, to compare estimates of resting energy expenditure (REE) with measured values. The 9 women and 3 men, whose mean age was 66.5+/-13.9 y, underwent nutritional assessment and measurement of their REE by indirect calorimetry using the Sensormedics Deltatrac MBM100 indirect calorimeter. Their REE was also estimated by the Harris-Benedict formula (mean 1032+/-66 kcal/d) as well as a previously established empirical formula where REE = 25 x body weight in kg (mean 1023+/-129 kcal/d). Results by both estimates were significantly lower than the measured resting energy expenditure (MREE) in this group of patients (P<0.0001). The percentage difference between MREE and estimated REE by the Harris-Benedict formula was 18.4+/-9.4% and 20.9+/-7.5% by the empirical formula. The MREE exceeded the estimated REE in each individual. The correlation between MREE and body weight (r2 = 0.558, r = 0.005) was better than that between MREE and estimated REE by Harris-Benedict formula (r2 = 0.275, P = 0.08) suggesting that weight was the principal determinant rather than the other components (height, age, sex) of the Harris-Benedict formula. Our data shows that commonly employed formulae routinely underestimate the energy needs of severely underweight patients below 50 kg in body weight. The Harris-Benedict equation had limited predictive value for the individual, explaining approximately 25% of the variance in energy expenditure. Given the particular importance of matching energy intake to needs in this group of patients with limited reserves, many of whom are critically ill, we suggest an empirical equation using 30-32 kcal/kg be used to estimate the energy requirements of severely underweight patients when direct measurements are unavailable or clinically less imperative.

Ulcerative Colitis and Sweet’s Syndrome: A Case Report and Review of the Literature

A 47-year-old man with a history of ulcerative colitis on prednisone and azathioprine was admitted to the hospital with a four-day history of fever, skin rash, arthralgias and leukocytosis. A skin biopsy demonstrated neutrophilic infiltration of the dermis that was consistent with Sweets syndrome. He improved after several days with an increase in his prednisone and azathioprine. Sweets syndrome is a rare cutaneous manifestation of inflammatory bowel disease, with approximately 40 cases reported in the literature. In a previously reported case of a patient with ulcerative colitis-associated Sweets syndrome who was on azathioprine at the time of the skin eruption, the azathioprine was stopped, raising the possibility of drug-induced Sweets syndrome. In the present case, the azathioprine was actually increased with complete resolution of the skin manifestations. This would support the theory that immunosuppressive therapy is the mainstay of therapy for this condition. In conclusion, Sweets syndrome is a neutrophilic dermatosis that is rarely associated with ulcerative colitis. It may occur while on immunosuppressive therapy and responds to an intensification of immunosuppression.

Appropriate Nutritional Support in Acute and Complicated Crohn’s Disease

Crohns disease is frequently complicated by protein-calorie malnutrition. Four common clinical presentations of Crohns disease include acute exacerbations or flares of disease, intestinal obstruction, fistulizing disease, and perianal disease. In this review, we examine the role of nutritional support in these clinical scenarios. Nutritional support is important for maintaining functional status and preventing loss of lean tissue. Determinants of lean-tissue loss include severity of underlying injury, baseline nutritional status, and duration of inadequate nutrition. One of the clinically useful measures of nutritional status is the nutritional risk index (NRI) defined on the basis of the serum albumin and weight loss. Nutritional support is important in severely malnourished patients (NRI < 83). Enteral nutrition is the route of choice, provided there are no contraindications to using the gastrointestinal tract. In acute exacerbations of Crohns disease, enteral nutrition also has a role in the primary management of disease although it is not as effective as corticosteroids in inducing remission. The mechanisms are poorly understood and the most effective enteral formulation needs to be determined. Total parenteral nutrition is justified in severely malnourished Crohns disease patients who are unable to tolerate enteral feeding or in whom enteral feeding is contraindicated. More clinical studies are needed on the assessment of malnutrition in Crohns disease, the effects of nutritional management on functional status, and the timing of nutritional intervention.

Peritonitis After Gastrostomy Tube Replacement Case Series and Review of Literature

BACKGROUND The placement of feeding gastrostomy (G) tubes through a percutaneous endoscopic gastrostomy (PEG) technique has become common because of its simplicity and safety. The majority of the serious complications are reported to occur within a few days of initial tube placement and happen in fewer than 3% of cases. Long-term reported complications of this procedure include occlusion or breakage of the G-tube, requiring reinsertion. This report describes the complication of intraperitoneal placement and the development of peritonitis after replacement of an established PEG tube and reviews the pertinent world literature. METHODS A retrospective review of cases of intraperitoneal insertion of replacement G-tubes was done as well as a Medline search for cases of intraperitoneal insertion of replacement G-tube or development of peritonitis after replacement tube insertion. RESULTS Three new cases of inadvertent intraperitoneal insertion of a replacement G-tube in adult patients with mature tracts are reported. An additional 5 cases have been previously described in adults. Significant morbidity was associated with this complication, and 4 deaths were related to it. Methods used to determine whether the replacement G-tube was intragastric were not uniform. CONCLUSIONS There have been few reports of intraperitoneal insertion of replacement G-tubes in patients with mature (>30 days) stoma sites. The cases presented in this report highlight for the clinician the importance of considering this complication, particularly if there are any difficulties with the reinsertion. Prospective studies are needed to determine the frequency of this complication and the optimal protocol for PEG replacement.

Survey of clinical nutrition practices of Canadian gastroenterologists

OBJECTIVE Nutrition education is a required part of gastrointestinal training programs. The involvement of gastroenterologists in clinical nutrition once their training has been completed is unknown. The aim of the present study was to determine the practice pattern of gastroenterologists in clinical nutrition and their perceived adequacy of nutrition training during their gastroenterology (GI) fellowship. METHODS The Canadian Association of Gastroenterology mailed a survey to all of its 463 Canadian clinician members and 88 trainee members. Components of the survey included knowledge of nutritional assessment and total parenteral nutrition, involvement in a nutrition support service, physician involvement in nutritional assessment and nutrition support teams, obesity management, insertion of gastrostomy (G) tubes and management of tube-related complications, and adequacy of training in clinical nutrition. RESULTS Sixty per cent (n=279) of the Canadian Association of Gastroenterology clinicians and 38% (n=33) of the fellows responded. Of the clinicians, 80% were practicing adult gastroenterologists with the following demographics: those practicing full time in academic centres (42%), community practice (45%), completed training in the last 10 years (32%) and those that completed training in the United States (14%). Although only 6% had a primary focus of nutrition in their GI practices, 65% were involved in nutrition support (including total parenteral nutrition), 74% placed G tubes and 68% managed at least one of the major complications of G tube insertion. Respondents felt a gastroenterologist should be the physicians consultant on nutrition support services (89%). Areas of potential inadequate training included nutritional assessment, indications for nutrition support, management of obesity and management of G tube-related complications. The majority of clinicians (67%) and trainees (73%) felt that nutrition training in their GI fellowship was underemphasized. CONCLUSIONS The majority of Canadian gastroenterologists are involved in nutrition support. However, this survey demonstrated that nutritional training is underemphasized in most training programs. It is important for GI fellowship programs to develop standardized nutrition training that prepares trainees for their practice.

Vitamin D deficiency in patients receiving home parenteral nutrition.

BACKGROUND In addition to its role in bone metabolism, vitamin D has important immunomodulatory and antineoplastic effects. Patients on home parenteral nutrition (HPN) receive most of their vitamin D from intravenous (IV) supplementation. Vitamin D deficiency is common in the general population, and the adequacy of vitamin D supplementation in HPN patients is unclear. The purpose of this study is to determine the vitamin D status of patients on HPN. METHODS Consecutive patients seen in a regional home nutrition program had their oral and IV vitamin D intakes determined. Plasma 25-hydroxyvitamin D levels were measured in all patients. Intake of calcium, magnesium, and phosphate were also determined. RESULTS The mean 25-hydroxyvitamin D level in 22 patients receiving HPN for a mean of 33.5 months (range, 1-177) was 42 nmol/L. Vitamin D deficiency was present in 15 (68%) patients and vitamin D insufficiency in 6 (27%) patients. The mean dietary vitamin D intake was 79.5 IU per day, while the mean IV supplementation was 166 IU per day. CONCLUSIONS In this study of a regional Canadian HPN program, there was a high prevalence of vitamin D deficiency/insufficiency affecting virtually all patients. All patients receiving HPN should be supplemented with vitamin D and have their 25-hydroxyvitamin D levels monitored. Further studies are required to determine optimal methods and dosing of vitamin D replacement using oral supplements or ultraviolet light therapy.

Risk of Symptomatic Central Venous Thrombotic Complications in AIDS Patients Receiving Home Parenteral Nutrition

BACKGROUND The acquired immunodeficiency syndrome (AIDS) is frequently complicated by malnutrition that may require parenteral nutritional support. In a non-AIDS population with long-term indwelling central venous catheters, low-dose warfarin therapy has been shown to prevent venous thrombosis. The purpose of this study was to determine the incidence of symptomatic central venous thrombosis in AIDS patients receiving home parenteral nutrition. The incidence of thrombosis on low-dose warfarin was compared with no prophylactic therapy. METHODS A retrospective review of 47 malnourished AIDS patients started on home parental nutrition was performed. None of the patients had a prior history of venous thrombosis. During this period, 9 of 47 patients were treated with low-dose warfarin therapy. The incidence of clinical and radiologic venous thrombosis was compared in these two groups. RESULTS Forty-seven patients were treated with parenteral nutrition for 296 patients-months. The rate of central venous thrombosis in patients receiving warfarin (0.016 thromboses per patient-month) was no different from those patients on no prophylactic therapy (0.009 thromboses per patient-month). The most common abnormality in coagulation observed in the entire group during follow-up was thrombocytopenia occurring in 66% of patients. Sixty percent of patients received medications that could interfere with platelet function. CONCLUSIONS We conclude that routine thrombosis prophylaxis with low-dose warfarin may not be justified in malnourished AIDS patients receiving home parenteral nutrition. Prospective clinical trials are needed to determine the risks and benefits of prophylactic warfarin therapy in this group of patients.

Essential fatty acid deficiencies in patients with chronic liver disease are not reversed by short-term intravenous lipid supplementation.

The purpose of this study was to determine theplasma triglyceride and phospholipid fatty acid (FA)composition of severely malnourished patients withchronic liver disease and to examine the effects of parenteral nutrition with a total nutrientadmixture (TNA) on these profiles. Nine consecutivepatients with end-stage chronic liver disease werecompared with 35 patients admitted for elective surgery of upper gastrointestinal malignancy. Baselinelaboratory values and the FA profiles of the plasmatriglyceride and phospholipids were analyzed. FAprofiles were also performed after infusion of a TNAincluding 33 ± 7 g of lipid/24 hr for 7.9 ±4 days in the patients with chronic liver disease.Compared with control patients, the plasma phospholipidfatty acid analysis results (relative mole percentage)of patients with chronic liver disease weresignificantly lower in the two essential FA, linoleicacid (15.4 ± 3.4% vs 20.8 ± 2.9%, P <0.001) and α-linolenic acid (0.02 ± 0.05%vs 0.08 ± 0.10%, P < 0.001). Similar changeswere demonstrated in the FA composition of thetriglyceride fraction. Short-term infusion ofintravenous lipid resulted in a significant increase inlinoleic acid in the triglyceride fraction (9.9 ± 2.8% beforesupplementation vs 20.7 ± 9.4% aftersupplementation, P < 0.01) and a decrease in oleicacid (38.7 ± 5.2% before supplementation vs 29.3± 7.5 after supplementation, P < 0.01). In conclusion, acute and chronicdeficiencies of essential FA occurs in patients withchronic liver disease. The clinical significance ofthese deficiencies is unknown, but they potentially may impact on eicosanoid metabolism. Short-termsupplementation with modest amounts of intravenous lipidhas only a minimal effect on normalization oflonger-chain fatty acids.

Electrolyte Abnormalities in Patients With Chronic Renal Failure Receiving Parenteral Nutrition

BACKGROUND AND METHODS Chronic renal failure frequently is complicated by elevations in serum potassium, phosphate, and magnesium. Consequently, parenteral nutrition (PN) solutions used to treat malnourished patients with chronic renal failure usually are prepared with little supplementation of these cations. Four malnourished patients with chronic renal failure and electrolyte abnormalities are reported. RESULTS Four patients developed significant hypophosphatemia 3 to 5 days after starting PN. Although carbohydrate infused via PN initially was not excessive (1.4 to 2.0 mg/kg/min), two patients received additional dextrose through continuous ambulatory peritoneal dialysis (CAPD). Two of the four patients received insulin during PN. Other electrolyte abnormalities included hypomagnesemia (1 patient) and hypokalemia (3 patients). CONCLUSIONS Malnourished patients with chronic renal failure receiving PN are at risk of developing electrolyte abnormalities, particularly hypophosphatemia. The electrolytes of these patients should be monitored closely when nutrition support is begun, and supplementation should be started as levels begin to fall within a normal range.