Computer-assisted glucose regulation during rapid step-wise increases of parenteral nutrition in critically ill patients: a proof of concept study.

BACKGROUND: Early delivery of calories is important in critically ill patients, and the administration of parenteral nutrition (PN) is sometimes required to achieve this goal. However, PN can induce acute hyperglycemia, which is associated with adverse outcome. We hypothesized that initiation of PN using a rapid "step-up" approach, coupled with a computerized insulin-dosing protocol, would result in a desirable caloric intake within 24 hours without causing hyperglycemia. METHODS: In our surgical intensive care unit (ICU), glucose is regulated by a nurse-centered computerized glucose regulation program. When adequate enteral feeding was not possible, PN was initiated according to a simple step-up rule at an infusion rate of 10 mL/h (approximately 10 kcal/h) and subsequently increased by steps of 10 mL/h every 4 hours, provided glucose was <10 mmol/L, until the target caloric intake (1 kcal/kg/h) was reached. All glucose levels and insulin doses were collected during the step-up period and for 24 hours after achieving target feeding. RESULTS: In all 23 consecutive patients requiring PN, mean intake was 1 kcal/kg/h within 24 hours. Of the 280 glucose samples during the 48-hour study period, mean ± standard deviation glucose level was 7.4 ± 1.4 mmol/L. Only 4.5% of glucose measurements during the step-up period were transiently ≥10 mmol/L. After initiating PN, the insulin requirement rose from 1.1 ± 1.5 units/h to 2.9 ± 2.5 units/h (P < .001). CONCLUSIONS: This proof of concept study shows that rapid initiation of PN using a step-up approach coupled with computerized glucose control resulted in adequate caloric intake within 24 hours while maintaining adequate glycemic control.

Immediate postoperative radiotherapy in residual nonfunctioning pituitary adenoma: beneficial effect on local control without additional negative impact on pituitary function and life expectancy.

PURPOSE: To demonstrate the benefit of immediate postoperative radiotherapy in residual nonfunctioning pituitary adenoma (NFA) in perspective to the need for hormonal substitution and life expectancy. METHODS AND MATERIALS: Retrospective cohort analysis of 122 patients, operated for NFA between 1979 and 1998. Recurrence was defined as regrowth on computed tomography or magnetic resonance imaging. The occurrence of hormonal deficiencies was defined as the starting date of hormonal substitution therapy. RESULTS: Seventy-six patients had residual NFA after surgery and received immediate postoperative radiotherapy (Group 1); three patients developed a recurrence, resulting in a 95% local control rate at 10 years. Twenty-eight patients had residual NFA after surgery, but were followed by a wait-and-see policy (Group 2). Sixteen developed a recurrence, resulting in a local control rate of 49% at 5 years and 22% at 10 years (p < 0.001 compared with Group 1). There were no differences between Group 1 and 2 regarding the need for substitution with thyroid hormone, glucocorticoids, and sex hormones before first surgery, directly after surgery and at end of follow-up. There were no differences in hormone substitution free survival between Group 1 and Group 2 during the study period after first surgery. Life expectancy was similar in Group 1 and 2, and their median life expectancy did not differ from median life expectancy in the general population. CONCLUSIONS: Immediate postoperative radiotherapy provides a marked improvement of local control among patients with residual NFA compared with surgery alone, without an additional deleterious effect on pituitary function and life expectancy.

Lack of radiation optic neuropathy in 72 patients treated for pituitary adenoma.

The incidence of radiation optic neuropathy (RON) after external photon beam radiation therapy for nonfunctioning pituitary adenoma (NFA) is not well-studied. Retrospective review of ophthalmological and imaging data in 72 patients with NFA treated between 1985 and 1998 with external beam radiation therapy after surgery Clinical follow-up after radiation therapy had to be at least 18 months. RON was defined as a sudden and profound irreversible visual loss affecting the optic nerve or chiasm A review of previously published cases of RON was then performed. In our cohort, no patient had RON. A total of 11 adequately documented series reports of RON were found in the medical literature on radiation-treated NFAs. The incidence of RON in NFA from these series is 0.53% (95% CI, 0.26%-0.96%). An additional 14 single RON cases have been reported, bringing the total of adequately documented RON cases to 25. RON is a rare complication after external beam radiation therapy for NFA.