The Incidence and Risk Factors of Apnea in Premature Infants underwent General Anesthesia for Cryotherapy or Laser Photocoagulation for Treatment of Retinopathy of Prematurity at Queen Sirikit National Institute of Child Health
Anchalee Attachoo MD*, Duenpen Horatanaruang MD*, Wanida Chongarunngamsang MD*, Suda Lauhsattana BN*
Affiliation : * Department of Anesthesiology, Queen Sirikit National Institute of Child Health, Bangkok, Thailand
Objective : To determine the incidence and risk factors of postoperative apnea in premature infants who received general
anesthesia for cryotherapy or laser photocoagulation for treatment of retinopathy of prematurity (ROP) at Queen Sirikit
National Institute of Child Health.
Material and Method: A retrospective cohort study was performed by reviewing medical records of premature infants with
ROP who underwent general anesthesia for cryotherapy or laser photocoagulation during January 2008 and December 2010
at Queen Sirikit National Institute of Child Health. The incidence and risk factors of postoperative apnea were analyzed.
Results : Forty of 167 (24%) premature infants had apnea after general anesthesia for treatment of ROP. The risk factors were
post-conceptual age and history of apnea. The risk of apnea in patients with post-conceptual age less than 35 weeks was 5.7
times higher than in patients with post-conceptual age more than 37 weeks (95%CI 1.59-20.45). Patients with a prior history
of apnea had a 6.42 times greater risk of postoperative apnea compared to patients without a prior history of apnea (95%CI
2.01-20.50). No other serious complications were reported during the study period.
Conclusion : The incidence of apnea after general anesthesia in infants with ROP treated with cryotherapy or laser
photocoagulation was 24%. The risk factors of postoperative apnea were post-conceptual age less than 35 weeks and prior
history of apnea. Patients with risk factors should be closely monitored.
Keywords : Anesthesia, Apnea, Cryotherapy, Laser photocoagulation, Premature infants, Retinopathy of prematurity
