The development of apnea following general anesthesia in high-risk infants (<60 weeks postconceptual age) has been reported up to 37% prompting the routine admission of these children following minor surgical procedures. One hundred forty high-risk infants (American Society of Anesthesiologists category ≥2) were prospectively evaluated after undergoing surgical procedures normally performed as outpatients in low-risk babies. All patients had spinal anesthesia for their operations. The mean gestational age for these infants was 30.8 ± 3.7 weeks (minimum. 24 weeks) with a mean birth weight of 1,466.0 ± 638.8 g. The mean postconceptual age and weight at the time of surgery were 44.8 ± 7.8 weeks and 3,336 ± 1,242 g respectively. Difficulty in administering the spinal anesthetic occurred in 6 cases (4.2%). Postoperative complications occurred in 5 children (3.8%). They were: postoperative fever (2) transient bradycardia (2) and apnea (1). The four cases of postoperative fever and bradycardia were insignificant and required no medical intervention. The single case of apnea occurred in a premature infant who received a supplemental dose of intravenous midazolam. Length of operation in these cases ranged from 15 minutes to 95 minutes (mean. 53 minutes) with two incidents of inadequate anesthesia occurring in this cohort. Mean duration of anesthesia was 146 minutes (range. 50 to 240 minutes) and was directly dependent on dosage administration of the agents. These data indicate that the use of spinal anesthesia in high-risk infants is safe and effective for surgical procedures generally performed as outpatients (3.0% minor complication rate. 0.8% major complication rate). No episodes of apnea or significant bradycardia developed in patients given only a spinal anesthetic; subsequently use of this technique appears to obviate the need for mandatory postoperative admission. With a minimum daily room and monitor charge of $513.20 at our institution this would result in a minimum savings of $65,176.40 for this cohort of patients.
Spinal anesthesia for pediatrics first appeared at the beginning of 20th century. After an initial period of disuse it has now gained popularity due to its favorable characteristics such as cardiovascular stability in children less than 5 years of age; satisfactory analgesia and muscle relaxation; the possibility of performing surgical procedures in patients at risk for general anesthesia (ie formerly preterm infants at risk for postoperative apnea); and the ability to administer small doses of local anesthetic (preferably hyperbaric tetracaine or bupivacaine) with consequent reduced toxic effects. This technique is limited mainly by a relatively short duration of anesthesia (surgical procedures generally cannot last more than 90 min) by the absence of satisfactory postoperative pain control and obviously by the lack of experience of anesthetist. Postdural puncture headache is rare. Although this technique could appear to be less invasive we recommend an accurate postoperative control for at least 12 hours.
The use of spinal anaesthesia in children has been primarily limited to situations in which general anaesthesia was considered to pose an excessive risk. The ex-premature infant and the neurologically impaired child account for the majority of spinal anaesthetics used today. Spinal anaesthesia compared with general anaesthesia in the ex-premature infant undergoing inguinal hernia repair has decreased postoperative respiratory complications (e g apnoeic events prolonged mechanical ventilation). Hyperbaric tetracaine and bupivacaine solutions are the local anaesthetics of choice. Haemodynamic stability is well preserved in neonates having spinal anaesthesia. Advances in spinal needle design have decreased the incidence of postdural puncture headache (PDPH). Catastrophic events have occurred with neuraxial techniques. Care must be taken in evaluating the relative risks of anaesthetic approaches in infants and children.
Spinal anesthesia is an extremely stable anesthetic in infants with minimal impact on cardiac and respiratory physiology. Initial reports centered on its use in minor surgical procedures such as inguinal hernia repair and circumcision. However its applications have broadened considerably over the past decade. Spinal anesthesia has now been reported for use in major surgical procedures in neonates including upper abdominal and cardiac surgery. As experience with the technique spreads its use will likely continue to increase. A limitation of spinal anesthesia in this ge group is its relatively brief duration of action and inability to provide analgesia into the postoperative period. Combined spinal and epidural techniques may be one solution to this problem.
Spinal anesthesia although uncommonly performed in infants and children may have a role in the premature infant predisposed to postoperative apnea and bradycardia. The duration of surgical anesthesia is often limited which leads to the necessity of adjuvant anesthetics. This article will describe the anatomy and physiology of the subarachnoid space of infants and children as well as discuss the technique of performing a subarachnoid block in this population. Judicious dosing and use of local anesthetics and potential adverse effects of this technique are discussed.
Forex Groups - Tips on Trading
Related article:
http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=IRSSCONTENT&_method=citationSearch&_piikey=S1084208X07000821&_version=1&md5=428ea612f4aff372c5b73fef7b15e8ec
comments | Add comment | Report as Spam
|