Again, premedication should be considered. It may sting but it usually has an effect within about 10 minutes. The increased ventilation through crying does not necessarily speed induction - the increased uptake merely compensates for the drug which has been redistributed to muscle. It is often said that children are like small adults. This is not so - for a start their proportions differ.
Infants have a relatively large head and therefore brain.
It must receive a greater proportion of cardiac output as a consequence. The surface area is larger and thus heat loss is increased when it is exposed, especially in neurosurgery. This is another key to working out important differences because if they need double the volume of oxygen then they have to double the amount taken in and transported. This means the alveolar ventilation must be increased which is largely achieved by increasing respiratory rate. Cardiac output must also be doubled to carry the oxygen around the body - this is achieved by increasing heart rate as babies have a very limited ability to increase stroke volume.