Validation of a method to partition the base deficit in meningococcal sepsis: a retrospective study

INTRODUCTION: The base deficit is a useful tool for quantifying total acid–base derangement, but cannot differentiate between various aetiologies. The Stewart–Fencl equations for strong ions and albumin have recently been abbreviated; we hypothesised that the abbreviated equations could be applied to the base deficit, thus partitioning this parameter into three components (the residual being the contribution from unmeasured anions). METHODS: The two abbreviated equations were applied retrospectively to blood gas and chemistry results in 374 samples from a cohort of 60 children with meningococcal septic shock (mean pH 7.31, mean base deficit -7.4 meq/L). Partitioning required the simultaneous measurement of plasma sodium, chloride, albumin and blood gas analysis. RESULTS: After partitioning for the effect of chloride and albumin, the residual base deficit was closely associated with unmeasured anions derived from the full Stewart–Fencl equations (r(2 )= 0.83, y = 1.99 – 0.87x, standard error of the estimate = 2.29 meq/L). Hypoalbuminaemia was a common finding; partitioning revealed that this produced a relatively consistent alkalinising effect on the base deficit (effect +2.9 ± 2.2 meq/L (mean ± SD)). The chloride effect was variable, producing both acidification and alkalinisation in approximately equal proportions (50% and 43%, respectively); furthermore the magnitude of this effect was substantial in some patients (SD ± 5.0 meq/L). CONCLUSION: It is now possible to partition the base deficit at the bedside with enough accuracy to permit clinical use. This provides valuable information on the aetiology of acid–base disturbance when applied to a cohort of children with meningococcal sepsis

Differential Expression between Human Dermal Papilla Cells from Balding and Non-Balding Scalps Reveals New Candidate Genes for Androgenetic Alopecia

Agency for Science, Technology and Research (A*STAR). EC is supported by the A*STAR Graduate Scholarship program

Defining phases for the sit-to-walk movement

Objective. To define phases of the sit-to-walk movement and test their consistency in a normal population. Design. An observational study of thirteen healthy volunteers. Background. Moving from sitting to walking is a daily activity that may present difficulty for some populations in terms of control and stability. Methods. The movement was partitioned into phases according to changes in ground reaction forces and peak velocity of the total body centre of mass. Consistency of each phase duration was assessed. Results. Four phases of sit-to-walk were defined; flexion momentum, extension, unloading and stance. ICC scores for phase duration ranged from 0.54 (extension) to 0.81 (stance). Conclusions. This is the first study to define distinct phases of the sit-to-walk movement. There was moderate to good consistency for phase duration

Relationship Between Arterial Partial Oxygen Pressure After Resuscitation From Cardiac Arrest and Mortality in Children

Background-Observational studies in adults have shown a worse outcome associated with hyperoxia after resuscitation from cardiac arrest. Extrapolating from adult data, current pediatric resuscitation guidelines recommend avoiding hyperoxia. We investigated the relationship between arterial partial oxygen pressure and survival in patients admitted to the pediatric intensive care unit (PICU) after cardiac arrest. Methods and Results-We conducted a retrospective cohort study using the Pediatric Intensive Care Audit Network (PICANet) database between 2003 and 2010 (n=122 521). Patients aged = 300 mm Hg) and 448 (24%) had hypoxia (PaO2 &lt;60 mm Hg). We found a significant nonlinear relationship between PaO2 and PICU mortality. After covariate adjustment, risk of death increased sharply with increasing hypoxia (odds ratio, 1.92; 95% confidence interval, 1.80-2.21 at PaO2 of 23 mm Hg). There was also an association with increasing hyperoxia, although not as dramatic as that for hypoxia (odds ratio, 1.25; 95% confidence interval, 1.17-1.37 at 600 mm Hg). We observed an increasing mortality risk with advancing age, which was more pronounced in the presence of congenital heart disease. Conclusions-Both severe hypoxia and, to a lesser extent, hyperoxia are associated with an increased risk of death after PICU admission after cardiac arrest.</p

Timing phases of the sit-to-walk movement: validity of a clinical test

The sit-to-walk (STW) movement is a functional task that challenges balance and co-ordination. There is a paucity of literature investigating the phases of this movement and its significance in a clinical rehabilitation context. Measuring phases of this movement may provide clinically applicable data for screening subjects for mobility problems and evaluating interventions. Fifty-six subjects from three groups; young (65 years old) and elderly at risk of falling (EARF), performed the STW movement freely from a chair. Switches placed on the backrest, chair seat and two on the floor identified the times of movement events: onset, seat-off, swing-off and stance-off. These events defined three phases: flexion, extension and stance. Timing of events and phase duration data derived from this switch system were correlated with those taken from a three-dimensional motion analysis system. All switch events closely matched the motion analysis events with ICC (model 2.1) scores ranging from 0.93 to 1.00. Duration of all STW phases were statistically longer in the EARF group compared to both unimpaired groups (p < 0.05). Data from the four switch configuration demonstrated excellent concurrent validity when associated with data from a three-dimensional motion analysis system in identifying the phases of STW. Measurement of the phases of the STW task has potential in screening those at risk of falling and informing care strategies to prevent falls