WSNs are a set of autonomous and tiny nodes deployed on a specific area to collect data from the environment. These nodes are limited in energy and processing resources, therefore a correctness planning in the transmission schemes of the nodes improves the WSN performance. Since WSNs are commonly deploy in non-ideal environments, the nodes usually communicate their data messages in a noisy channel. Specifically, we propose three unscheduled transmission schemes for control packets: Fixed Scheme (FS), Adaptive by Estimation Scheme (AES) and Adaptive by Gamma Scheme (AGS), they are based on contention mechanisms such as the CSMA-NP protocol (Carrier Sense Multiple Access No Persistent). Thus, this study focuses on the sending of control packets where channel conditions are unfriendly, for instance, with presence of noise, interferences and attenuations of the signal. As such, we looked for mechanisms that adjust the nodes’ transmission to the channel conditions to reduce energy consumption and reduce the delay in the network due to this process of sending of control packets. The experimental results of this study suggest that adaptive schemes are preferable for the transmission of the nodes in noisy channels, such that energy consumption and delay are reduced significantly when it carefully chooses setting parameters, as in this work is made.