Abstract
Background
Earlier initiation of therapeutic hypothermia in term infants with hypoxic-ischemic encephalopathy has been shown to improve neurological outcomes. The objective of the study was to compare safety and effectiveness of servo-controlled active vs. passive cooling used during neonatal transport in achieving target core temperature.
Methods
We undertook a prospective cohort quality improvement study with historic controls of therapeutic hypothermia during transport. Primary outcome measures were analyzed: time to cool after initiation of transport, time to achieve target temperature from birth and temperature on arrival to cooling centers. Safety was assessed by group comparison of vital signs, diagnosis of persistent pulmonary hypertension (PPHN) and coagulation profiles on arrival.
Results
A total of 65 infants were included in the study. Time to cool after initiation of transport and time to achieve target temperature from birth were statistically significantly shorter in the actively cooled group with time reduction of 24% with P<0.01 and 15.6% with P<0.01, respectively. On arrival to our cooling center, we noted a significance difference in the mean core temperature (active 33.8°C vs. passive 35.4°C, P<0.01). Seven percent (2/30) of infants in the passively cooled group were overcooled (temperature <33°C). Patients in the actively cooled group had significantly lower mean heart rate compared to the passively cooled group. There was no statistically significant difference in diagnosis of PPHN or coagulation profiles on admission.
Conclusion
Our study indicates that active cooling with a servo-controlled device on neonatal transport is safe and more effective in achieving target temperature compared to passive cooling.
With the rise in awareness of energy efficient buildings and adoption of mandatory energy conservation codes across the globe, significant change is being observed in the way the buildings are designed. With the launch of Energy Conservation Building Code (ECBC) in India, climate responsive designs and passive cooling techniques are being explored increasingly in building designs. Of all the building envelope components, roof surface has been identified as the most significant with respect to the heat gain due to the incident solar radiation on buildings, especially in tropical climatic conditions. Since ECBC specifies stringent U-Values for roof assembly, use of insulating materials is becoming popular. Along with insulation, the shading of the roof is also observed to be an important strategy for improving thermal performance of the building, especially in Warm and humid climatic conditions. This study intends to assess the impact of roof shading on building’s energy performance in comparison to that of exposed roof with insulation. A typical office building with specific geometry and schedules has been identified as base case model for this study. This building is simulated using energy modelling software ‘Design Builder’ with base case parameters as prescribed in ECBC. Further, the same building has been simulated parametrically adjusting the amount of roof insulation and roof shading simultaneously. The overall energy consumption and the envelope performance of the top floor are extracted for analysis. The results indicate that the roof shading is an effective passive cooling strategy for both naturally ventilated and air conditioned buildings in Warm and humid climates of India. It is also observed that a fully shaded roof outperforms the insulated roof as per ECBC prescription. Provision of shading over roof reduces the annual energy consumption of building in case of both insulated and uninsulated roofs. However, the impact is higher for uninsulated roofs (U-Value of 3.933 W/m2K), being 4.18% as compared to 0.59% for insulated roofs (U-Value of 0.33 W/m2K).While the general assumption is that roof insulation helps in reducing the energy consumption in tropical buildings, it is observed to be the other way when insulation is provided with roof shading. It is due to restricted heat loss during night.
Clinical deterioration during neonatal transport in California
