Carbohydrate ingestion attenuates the reduction in complex cognitive function and cerebral blood flow during prolonged passive heat stress in humans.

PURPOSE: To determine whether carbohydrate ingestion would reduce cognitive dysfunction in humans following long duration passive heat stress (PHS) versus consuming electrolytes alone. METHODS: Fifteen young (27 ± 4 y) healthy adults were exposed to 120 min of PHS through the use of a liquid perfused suit (50 °C) on two randomized visits. Subjects consumed fluids supplemented with electrolytes (E) or electrolytes + carbohydrates (E + C). Pre- and post-heat stress, body mass (BM) and plasma osmolality (pOsm) were measured. Heart rate (HR), blood pressure (BP), Physiological Strain Index (PSI), core temperature (Tc), plasma glucose, respiration rate (RR), end-tidal CO2 (PetCO2) and internal carotid artery (ICA) blood flow were recorded at baseline and every 15 min of heat stress. Cognitive function was assessed via the Automated Neuropsychological Assessment Metric at baseline and at 30- and 120 min during heat stress. RESULTS: There were no significant differences between fluid conditions for BM, pOsm, PSI, Tc, RR or PetCO2. Plasma glucose was ∼75% greater in the E + C condition compared to the E condition after 90 min of PHS (P < 0.05). Cognitive function (120 min) was impaired following PHS only in E condition (P < 0.05) and performance on complex cognitive tasks were better by ∼22-340% in the E + C vs. E (P < 0.05). Compared to the E condition, HR and BP were lower and ICA blood flow, vascular conductance, and glucose delivery was ∼90% greater in the E + C after 90 min of PHS (P < 0.05). CONCLUSIONS: These data are the first to demonstrate that carbohydrate ingestion may have a protective effect on cognitive function during long duration PHS. Furthermore, this protection was associated with preserved ICA blood flow and glucose delivery to the brain.

The influence of adjuvant therapy on cardiorespiratory fitness in early-stage breast cancer seven years after diagnosis: the Cooper Center Longitudinal Study.

We examined cardiorespiratory fitness (CRF) levels in early stage breast cancer patients and determined whether CRF differs as a function of adjuvant therapy regimen. A total of 180 early breast cancer patients representing three treatment groups (surgery only, single-, and multi-modality adjuvant therapy) in the Cooper Center Longitudinal Study (CCLS) were studied. A non-cancer control group (n = 180) matched by sex, age, and date of the CCLS visit was included. All subjects underwent an incremental exercise tolerance test to symptom limitation to assess CRF (i.e., peak metabolic equivalents [METs] and time to exhaustion). The mean time from breast cancer diagnosis to exercise tolerance testing was 7.4 ± 6.2 years. In adjusted analyses, time to exhaustion and peak METs were incrementally impaired with the addition of surgery, single-, and multi-modality adjuvant therapy compared to those of matched controls (p = 0.006 and 0.028, respectively). CRF was lowest in the multi-modality group compared to all other groups (all p's < 0.05). Despite being 7 years post-diagnosis, asymptomatic early breast cancer survivors have marked reductions in CRF. Patients treated with multi-modal adjuvant therapy have the greatest impairment in CRF.

Evaluation of the R2D2 protocol: A Novel Method for Assessing Emergency Department Disposition for Residents.

BACKGROUND: The emergency department (ED) disposition and discharge process is a critical period in a patient's transition from an acute care setting to self-care or a bridge to other healthcare providers. The emergency physician plays a pivotal role in this process and is ultimately responsible for ensuring that patients are safely released from their care. We developed a protocol to guide residents through the ED discharge process using the mnemonic "R2D2": reassess the patient, recheck the workup, discuss the disposition plan with the attending, and finally discuss the discharge plan with the patient. OBJECTIVES: The objective was to assess the effectiveness of the R2D2 discharge protocol, executed by resident physicians, in improving patients' understanding of their diagnosis and treatment plans. METHODS: This is a before-and-after study in the ED of a county hospital and included all patients discharged by a resident physician from the ED 1 week before and 1 week after implementation of the R2D2 protocol. All participating resident physicians received a brief 10-minute orientation to the R2D2 protocol at the end of the first week of the study period. Consecutive patients were identified, consented, and given a brief questionnaire about their discharge by research assistants. Certain exclusion criteria applied such as inability to speak English or Spanish or no phone for follow-up. One to 2 weeks after ED discharge, patients from both groups were contacted by phone to assess their recall of their discharge instructions. Data analyses were performed using Fisher's exact, chi-square tests, or two independent-sample proportions tests as appropriate. RESULTS: We recruited 164 patients in the control group and 148 patients in the intervention group, totaling 312 patients. A total of 73.8% of the control group patients and 77.0% of the intervention group patients completed the follow-up. On telephone follow-up, 88% of the intervention patients knew their discharge diagnosis versus only 74% of control patients (p = 0.0062). Eighty percent of intervention patients knew their discharge treatment plan versus only 67% of control patients (p = 0.0259). CONCLUSIONS: The R2D2 protocol resulted in significant improvement in patients' understanding of their discharge diagnosis and treatment plan.