former than 如何理解？

The routine use of opioids in PS patients is typically avoided. It is well known that the former premature infant that is less than 60 weeks PCA is at an increased risk of postoperative apnea after general anesthesia [41]. However, the incidence of apnea occurring in term neonates following general anesthesia is less clear, although it certainly exits [55]. Neonates respond to opioids differently than adults. They are more susceptible to the respiratory depressive effects of opioids. This is likely due to an incomplete blood-brain barrier allowing higher concentrations of opioids to reach the central nervous system [56]. Opioids are metabolized slower in neonates leading to higher plasma concentrations and longer elimination half-lives. [57]. The patient with PS has the additional risk of apnea related to cerebrospinal fluid alkalosis that may persist even though the acid-base balance of the blood has been corrected [23, 58]. A study by Habre et al. [59] o n pain control after pyloromyotomy found that wound infiltration with bupivacaine delayed the need for other analgesics (acetaminophen) for up to 9 h. It was also noted that the use of intraoperative opioids was associated with naloxone administration in 10% of cases studied. If the practitioner feels that opioids must be administered, great care must be taken. Opioids should be given in the lowest effective doses after the patient is extubated, awake, and in an adequately monitored setting.

former 如何理解？than如何理解，除了？ 谢谢