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A central venous catheter (CVC) is widely regarded as the standard route for delivery of intravenous nutrition (IVN). Peripheral venous infusion avoids the morbidity of a CVC, but may require regular resiting of standard intravenous cannulae, or compromise of the nutritional quality of the feed, to avoid thrombophlebitis. Fine-bore catheters, designed for use in neonates, have been associated with a much lower incidence of phlebitis when used for peripheral IVN in adults, but reports have been limited to selected groups of patients. A prospective study of 302 courses of IVN is presented in which a peripheral vein was the route of first choice. The composition of the feed was determined by the patient's metabolic requirement, and was not compromised to facilitate peripheral venous infusion. In 51% of all courses of IVN the peripheral route alone was used; 76% of patients who received peripheral IVN required only one fine-bore catheter.

The majority of patients with acute pancreatitis require little specialist treatment, can be managed on a general surgical ward and, if gallstone induced should undergo cholecystectomy (or endoscopic sphincterotomy if frail) during the recovery phase of their illness. A minority of patients develop severe attacks and should undergo extensive clinical, biochemical and radiological evaluation to determine the requirement for intensive care admission. Failure to improve despite maximal supportive therapy in the setting of documented pancreatic necrosis, infected pancretic necrosis on percutaneous fine needle aspiration and the development of specific complications are relative indications for surgical debridement of the necrotic retroperitoneum. The majority of severely ill patients require parenteral nutrition, frequent reassessment and often protracted admission to the ICU. These are the patients in whom experimental therapies may be useful in the future such as oxygen free radical scavengers.

The influence of short-term pre-operative intravenous nutrition (IVN) upon protein synthesis in human liver and skeletal muscle was investigated in 30 patients with weight loss (>5 kg in preceding 3 months) who underwent resection of a neoplasm of the gastrointestinal tract. Patients were randomised to receive a normal hospital diet (HD group) or a hospital diet supplemented by intravenous nutrition (IVN groups; 0.18 gN/kg/24h as FreAmine III; 126kJ/24h as glucose) for either 3 (IVN3) or 7 days (IVN7) Nutritional assessment was undertaken by measurement of anthropometric, biochemical and immunological indices. In addition, the rates of protein synthesis in biopsies of liver and skeletal muscle, which were obtained at operation, were determined in vitro from the incorporation into protein of 14C-leucine. Patients who received a hospital diet only (HD group) were in negative energy balance and continued to lose weight during the pre-operative period. The imbalance between caloric intake and expenditure was met from endogenous fuel stores with a reduction in fat-free mass and arm muscle area. Patients who received IVN maintained body weight and fat-free mass and had higher rates of protein synthesis in liver and skeletal muscle. In addition there was an increase in the plasma concentrations of prealbumin, haptoglobin and complement C3 together with a rise in the concentrations of the circulating immunoglobulins IgM and IgA. The majority of these changes occurred after only 3 days of IVN.

Discussion over the role of enzyme therapy in patients with acute pancreatitis is based upon theoretical considerations rather than hard data. In this respect, it differs little from most other treatments used in the management of acute pancreatitis, although, in the case of enzyme treatment, the lack of data results largely from a dearth of experimentation to prove its efficacy rather than from equivocal or negative results.

A prospective randomised controlled trial of prophylaxis with oral stanozolol compared to standard low-dose subcutaneous heparin in prevention of deep venous thrombosis was carried out in 223 patients undergoing elective major abdominal surgery. A predictive index was used to divide the patients into high and low risk groups. Patients at high risk were randomised to receive either stanozolol, 10 mg orally daily for 2 weeks before operation and 1 week post-operatively, or subcutaneous heparin, 5000 units 2 h pre-operatively and 8 hourly thereafter for 1 week. Patients classified at low risk did not receive specific prophylaxis. Post-operative deep venous thrombosis was diagnosed by leg scanning following administration of iodine-125 labelled fibrinogen and the diagnosis confirmed by venography. Nine of 136 patients at low risk (6.6%) developed deep venous thrombosis. Nine of the 45 patients at high risk who received stanozolol (20%) developed DVT assessed by leg scan and 5(12/) determined by venography. In contrast only one of the 42 patients at high risk who received prophylaxis with heparin (2.4%) developed a positive leg scan and the diagnosis was not confirmed at venography. The differences between the numbers of patients who developed DVT in the two treatment groups were statistically significant both in terms of leg scanning (p=0.009) and of venography (p=0.03). Administration of oral stanozolol resulted in a significant increase in fibrinolytic activity pre-operatively, though it did not prevent the marked reduction in fibrinolysic activity which is known to occur on the first post-operative day. In spite of this presumably beneficial effect on fibrinolysis, stanozolol was significantly less effective than low-dose heparin in prevention of DVT.

The advantages of silicone rubber central venous catheters are widely recognised, but embolisation of the whole catheter can occur due to malfunction of the hub which is used to clamp the catheter to the female luer connector. Two cases are described in which silicone rubber catheters were successfully removed from the heart using percutaneous techniques. A modification is suggestion to prevent this complication.

The clinical value of objective measurement of skeletal muscle function was studied in 37 pre-operative patients with carcinoma of the gastrointestinal tract. Muscle function was determined in the adductor pollicis muscle of the thumb after stimulation of the ulnar nerve at the wrist. There was a difference in the force-frequency relationship (F10/F100) between patients with a recalled weight loss of 5 kg or more in the 3 months prior to admission compared to those who had not lost weight. Muscle function was normalized by 7 days of pre-operative intravenous nutrition. Pre-operative measurement of skeletal muscle function enabled identification of patients who subsequently developed a post-operative complication with a specificity of 89%, sensitivity of 39% and predictive index of 78%. Objective measurements of skeletal muscle function are of potential value for the prediction of post-operative complications, and may help to define patients who need nutritional support.

Radiographs taken on the day of admission on 52 patients with acute pancreatitis have been compared with similar radiographs of 30 patients with acute cholecystitis and 22 patients with perforated duodenal ulcer. Two radiologists, who were unaware of the clinical features, looked specifically for the presence of 30 radiological signs. The only abdominal signs seen more frequently in acute pancreatitis were fluid levels in the stomach and duodenum, usually associated with dilatation. Duodenal abnormalities were seen in 42% of patients with acute pancreatitis and 21% of the controls (P less than 0.05) while gastric dilatation with a fluid level was seen in 29% of cases of acute pancreatitis compared with 12% of controls (P less than 0.05). Seventy per cent of the patients with severe acute pancreatitis had an abnormal chest radiograph on admission compared with 18% of those with mild disease. Left pleural effusion was the most common abnormality in severe pancreatitis (43%) and was seen significantly more often than in mild pancreatitis (P less than 0.01) and the control group (P less than 0.05). Therefore, consideration of the admission chest radiograph may help at an early stage to distinguish patients with severe pancreatitis from those with mild disease.