Association of metabolic acidosis with bovine milk-based human milk fortifiers.

OBJECTIVE: To compare the incidence of metabolic acidosis and feeding intolerance associated with powdered or acidified liquid human milk fortifier (HMF). STUDY DESIGN: This retrospective study evaluated infants ⩽ 32 weeks gestational age or ⩽ 1500 g birth weight who received human milk with either powdered or acidified liquid HMF (50 consecutively born infants per group). Primary outcomes tracked were metabolic acidosis (base excess less than -4 mmol l(-1) or bicarbonate less than 18 mmol l(-1)), feeding intolerance (gastric residual > 50% feed volume, > 3 loose stools or emesis per day, abdominal tenderness or distention), necrotizing enterocolitis, late-onset infection, death, length of hospital stay and ability to remain on HMF. Demographics, feeding practices, growth parameters and laboratory data were also collected. RESULT: Significantly more infants who received acidified liquid HMF developed metabolic acidosis (P < 0.001). Base excess and bicarbonate were both significantly decreased after HMF addition in the liquid HMF group (base excess P = 0.006, bicarbonate P < 0.001). More infants were switched off liquid HMF due to metabolic acidosis or feeding intolerance than those on powdered HMF (P < 0.001). Despite increased protein intake in the liquid HMF group (P = 0.009), both groups had similar enteral caloric intakes with no difference in growth rates between the two groups. There was no significant difference in any of the other primary outcomes. CONCLUSION: Infants receiving acidified liquid human milk fortifier were more likely to develop metabolic acidosis and to be switched off HMF than those who received powdered HMF. Growth in the liquid HMF group was no different than the powdered group, despite higher protein intake.

Rethinking functional limitation pathways.

Functional limitation has received considerable attention in gerontology and geriatrics. Much of this work has focused on single-wave transitions devoid of context rather than on the pattern of transitions over time that constitute trajectories. This Forum article suggests that it is time for a different way of looking at functional limitation pathways. It focuses on trajectories. Responses to three Rosow and Breslau (1966) and two Nagi (1976) items, asked of 12,998 older adults who participated in up to seven waves of data collection as part of the Established Populations for the Epidemiologic Study of the Elderly, are used to illustrate this approach, emphasizing both its conceptual and pragmatic advantages. The results provide greater clarity in terms of those who become functionally limited, take on more functional limitations, or recover as well as those who are likely to be lost to follow-up and in terms of the outcomes associated with those individuals over time.