The optokinetic cervico reflex during simulated helicopter flight.

INTRODUCTION: The optokinetic cervico reflex (OKCR) is a recently hypothesized, visually driven reflex that serves to stabilize the image of the external horizon on the retina during roll maneuvers in high-performance aircraft. Although reported anecdotally, head tilt during helicopter flight has not been studied formally. Such research is required to determine the full impact and significance that it may have on the flying performance of a rotary-wing aviator. OBJECTIVE: The aim of this study was to investigate the relationship between horizon position and the perception of orientation and, thus, to generate vital information to assess whether OKCR plays an important role in spatial disorientation. HYPOTHESIS: Pilots of rotary-wing aircraft will exhibit the OKCR. METHODS: A UH-60 flight simulator study, with 20 volunteer pilots participating, was performed to examine the effects of this reflex during day flight and during flight with night vision goggles (NVGs). RESULTS: The results confirm that the OKCR occurs during simulated helicopter flight, both with and without NVGs. As with previous studies, head roll increased during flight under visual meteorological conditions in relation to an increasing aircraft roll angle up to a maximum sustainable level and then remained constant. Head roll did not occur during flight under instrument meteorological conditions. CONCLUSION: The presence of the OKCR will impact rotary-wing operations. Various aspects are discussed, and recommendations are made for future research.

Falls risk factors in an acute-care setting: a retrospective study.

Research findings have been contradictory regarding risk factors for falls in the acute-care setting. Identification of factors that place individuals at risk of falling in this setting are a priority because falls result in high morbidity and mortality and thus increased healthcare costs. The purpose of this study was to extend knowledge beyond the known risk factors of age and medical diagnosis by comparing the characteristics of 301 adults who fell while hospitalized with a matched sample of adults who did not fall while hospitalized. A descriptive, retrospective, comparative design was used. The fall and non-fall group were matched on age and primary medical diagnosis at the time of discharge. Data were collected from hospital incident reports and medical records. Logistic regression for matched groups identified 5 risk factors, as follows. Incontinence. The odds of falling were 11.3 (CI = 3.85, 33.05) times greater for those who were incontinent than for those who were not incontinent. Long hospital stay. The odds of falling were 9.9 (CI = 4.89, 19.88) times greater for those hospitalized 19 days or longer than for those hospitalized less than 19 days. Dependency for ambulation. The odds of falling were 6 (CI = 2.83, 12.84) times greater for those who were dependent for ambulation than for those who were independent. Independency for hygiene. The odds of falling were 2.5 (CI = 1.23, 4.88) times greater for those who were independent for hygiene than for those who were dependent. Lack of regular exercise. The odds of falling were twice as high (CI = 1.00, 3.82) for those who did not exercise regularly as for those who exercised regularly. These findings suggest that ongoing assessment may be more important than the admission assessment in identifying risk factors for falls in the acute-care setting. No 2 studies have found exactly the same set of risk factors, although some findings are consistent across studies. This suggests that those risk factors that are consistent across studies may identify persons who are at the greatest risk for falls and that other risk factors for falls are specific to a patient population.

Validation of a nutritional screen in children with respiratory syncytial virus admitted to an intensive care complex.

OBJECTIVE: We sought to validate a nutritional screen that was easy to perform and accurate in identifying pediatric patients at risk for adverse clinical outcomes based on their nutritional status. METHODS: Twenty-five consecutive patients admitted to our pediatric intensive care complex between July 1992 and July 1993 with a primary diagnosis of respiratory syncytial virus infection were evaluated. Nutritional screen parameters included historical (disease and condition), growth (anthropometrics), and laboratory (hemoglobin, lymphocyte count, and albumin) data. Outcome measures included days in the hospital, days of mechanical ventilation, days not fed enterally, and days receiving oxygen. RESULTS: Regression analysis indicated that a score of 5 or less signified a low risk of adverse outcome and a score of greater than 5 signified a high risk. Eleven of 25 patients had low scores, and 14 of 25 had high scores. All outcome measures differed significantly between the low- and high-risk groups: median number of days in the hospital, 7 and 13.5, respectively; median number of days of ventilation, 0 and 8.5, respectively; median number of days without enteral feeding, 3 and 8.5, respectively; and median number of days receiving oxygen, 4 and 20, respectively. CONCLUSIONS: Our nutritional screen identifies patients in the pediatric intensive care complex with respiratory syncytial virus at increased risk for adverse outcome. This screen may be useful in identifying pediatric patients at risk for adverse clinical outcomes from other medical diagnoses.