Opiod Actions on the Bulbar Respiratory Network: Consequences for Breathing (pp. 67-88)
Authors: (Peter M. Lalley, Department of Neuroscience, The University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA)
Abstract: Opiates are among the most effective drugs against pain, smooth muscle spasticity, persistent coughing, and are widely used as adjuncts to general anesthesia during surgical procedures. However, respiratory depression and postoperative opioid disturbances of ventilation are major, potentially lethal side effects that complicate the therapeutic effectiveness of opioid drugs.
This review of opioid actions on the bulbar respiratory network is directed at current perspectives related to where and how opioid drugs of therapeutic importance depress respiration in the CNS and cause disturbances of ventilation.
Animal studies that describe the distribution of opioid receptors in the brainstem respiratory network will be discussed in connection with the effects of exogenous opioids on respiratory neurons and ventilation.
The animal studies will be compared with opioid effects on breathing and ventilation in human subjects. Several pharmacological strategies have been tested in humans and nonhuman mammals to reverse opioid depression of breathing.
There is a particular need to develop effective drug countermeasures against respiratory depression without compromising therapeutic effectiveness in patients that need chronic opioid therapy. Some treatments that have been tested and their effectiveness are discussed in this review.