Emergence agitation R2 顏廷珊

一切都是想像力的問題。我們的責任從想像力中開始。葉慈這樣寫。 In dreams begin the responsibilities –正是這樣。反過來說，沒有想像力的地方或許也不會產生責任。 - 村上春樹 <海邊的卡夫卡> p.187

Emergence “delirium” after sevoflurane anesthesia: a paranoid delusion ? Anesthesia & analgesia, 1999 June, volume 88(6), P 1308-10; case report

Case 1: 24 y/o male, 62 kg,ASA I,for irrigation and debridement of right fifth digit; induction with O2, N2O, sevoflurane, fentanyl 50 ug; on emergence, an episode of hallucination lasting for 20 min; full record of all post-op events; denied experiencing any pain

Case 2: 8 y/o girl, 34kg, ASA I, for incision and drainage of a submandibular lymph node abscess; premedication with midazolam 1.5 mg IV, no distress separating from her family; induction with propofol IV and maintenance with O2, N2O, and sevoflurane; fentanyl 100 ug IV in divided doses; deep extubation; on awakening, she was very frightened and extremely agitated; for 15 min; no pain

Case 3: 4 y/o boy, 22 kg, ASA I, for dental rehabilitation; premedication with oral midazolam 0.5 mg/kg, separated from her family well; induction with sevoflurane, O2, maintenance with sevoflurane, fantanyl 2ug/kg for divided doses; on emergence, extremely agitated, screaming “I’m afraid, don’t touch me”; finally sedated with fentanyl and midazolam; he reawakened calm

Case 4: 3 y/o girl, 18 kg, ASA II, for revision of a V-P shunt; no history of anesthetic complication or postoperative dysphoria; premedication with midazolam 0.5mg/kg, separating with her family well; induction with O2 and sevoflurane; pancuronium 0.1mg/kg and fentanyl 2ug/kg; awake extubation; agitated an inconsolable for 20-30 min; very ,very frightened “I thought you ere going to hurt me…”; denied any painh

Discussion Emergence from sevoflurane: agitated, restless, combative, and extremely frightened, do not fully recognize surroundings Paranoid ideation Rapid awakening ? Postoperative analgesia ? All patient soon returned to themselves, can recall all the events during emergence

It would be interesting to know whether occurrence of this organic psychosis after sevoflurance anesthesia is associated with subsequent behavioral abnormalities Misperception of environmental stimuli

We observed that anxiolytic premedication and effective analgesia in pediatric patients does not necessarily prevent emergence delirium In our experience, the use of high concentrations of sevoflurane to delay emergence cannot be relied on to avert this outcome, maintaining with different volatile agents after sevoflurane induction has also been ineffective

Different central effects from halothane; neurotransmitter changes? Ketamine: inhibition of glutamine at NMDA receptors Droperidol: inhibition of dopamine 1 and 2 receptors Scopolamine: increasing central acetylcholine concentrations

Emergence delirium after sevoflurane anesthesia is a short-lived, acute organic mental state of uncertain etiology Further studies exploring the neuropsychopharmacological properties of sevoflurane, its metabolites, and other inhaled anesthetics may explain these behavioral patterns

A prospective cohort study of emergence agitation in the pediatric postanesthesia care unit Anesth analg 2003;96:1625-30

Postanesthetic excitement, emergence delirium, emergence agitation Nonpurposeful restlessness and agitation, thrashing, crying or moaning, disorientation, and incoherence, paranoid ideation Long-term psychological implication remain unknown Epidemiology: 5.3% in all patient awake from GA, 12-13% in children

Methods 3-7 y/o children, ASA I-II, cognitively intact, undergoing GA for an outpatient surgical procedure The child’s behavior during separation from parents and the induction of GA ( calm/cooprative, slightly anxious/tearful, agitated/uncooperative) Anesthetics and perioperative medications, the duration of anesthesia, time to awakening PACU nurses presence or absence of EA ( nonpurposeful movement, restlessness, thrashing, incoherence, inconsolability, unresponsiveeness) Parents of these children completed behavioral style questionnaire

Results 521 children over 1 year period EA: younger, have had previous surgery

Adaptability

ENT and ophthalmologic procedure Sevoflurane or isoflurane: most frequently; pentothal: less frequently Sevo/ iso: twice likely to EA than other agents All EA children received intraoperative analgesics (98%), compared with 86% of nonEA No difference in the duration of anesthesia EA group had a significantly shorter time to awakening

Agitation time: 3-45 min, mean: 14+/-11 min EA prolonged PACU stay( 117+/- 66min vs 101+/- 61 min, P= 0.02) Thrashing 86%, kicking 64%, restless and incoherent 14% 60% in EA group required physical restraint, 42% required >2 nurses

EA subsided without pharmacological intervention in 48%, the duration of EA in these children was shorter than those with EA were treated ( 11+/-10 min vs 16+/-10 min, P = 0.02) EA: 52% 46 children needed an opiate, 2 BZD, 2 both; only 18% 77 children needed pharmalogical intervention Adverse events: increased bleeding from surgical site; pulling out a surgical drain or an IV; increased pain at the operative site; minor injury of the nurse

Discussion Volatile agents 24-66% Abrupt emergence Rapid emergence, prolong PACU stay

Pain EA: pain during impaired consciousness; however no clear relationship Preemptive oxycodone reduced postanesthesia agitation for children: in halothane group but not sevoflurane group Analgesics cannot completely attenuate postanesthetic agitation; another mechanism for EA?

Surgical procedure ENT procedure “sense of suffocation”

Patient related factors Young age Anxiety or distress Preoperative midazolam or clonidine: slowed awakening rather than anxiety One study found that children who received midazolam experienced EA more frequently than those who did not and that the observed agitation lasted longer BZD : associated with paradoxical reaction and agitation

No relationship between behaviors at separation and induction and those at emergence Lower thresholds, low adaptability

Conclusion EA reamins a significant postanesthetic problem that interferes with child’s recovery and challenges the PACU care provider in terms of assessment and treatment This study identifies multiple factors associated with EA, of which short time to awakening, use of isoflurane, and otorhinolaryngologic procedures were independent risk factors

Prevention

The effect of caudal analgesia on emergence agitation in children after sevoflurane or halothane anesthesia anesth analg 2004;98:321-6 Sevoflurane anesthesia in young children has been associated with an increased incidence of emergence agitation compared with halothane. Postoperative pain may be an etiologic factor 8 children undergoing inguinal hernia repair randomly assigned to sevoflurane or halothane groups Caudal block Sevoflurane was associated with a greater incidence of emergence agitation than halothane Emergence agitation appears to be an early and transient phenomenon after sevoflurane anesthesia in children with effective postoperative anaglesia

The effect of fentanyl on the emergence characteristics after desflurane or sevoflurane anesthesia in children Anesth analg 2002;94:1178-81 Desflurane and sevoflurane anesthesia are associated with emergence agitation in children 100 2-7 y/o children, adenoidectomy, gas induction with sevo or des- fluran, 2.5 ug/kg dose of fentanyl The results showed a similar incidence of severe emergence agitation after GA with desflurane and sevoflurane Times to extubation and PACU discharge: sevo>des With this technique, desflurane allows for a more rapid emergence and recovery than sevoflurane 2.5 ug/kg fentanyl results in a small incidence of emergence agitation

Clonidine prevents sevoflurane induced agitation in children In a double-blinded trial, 40 male children (age 2–7 yr) undergoing circumcision were randomly assigned to receive clonidine 2 µg/kg IV or placebo after anesthetic induction. For induction and maintenance of anesthesia, we used sevoflurane as the sole anesthetic. For pain treatment, a penile block was performed before surgery. After surgery the incidence and severity of agitation was mea-sured during an observation period of 2 h. Severe agitation was treated with midazolam. In 16 placebo and 2 clonidine-treated patients agitation was observed (P < 0.001). In 6 patients of the Placebo group, agitation was graded as severe, whereas none of the patients in the Clonidine group developed severe agitation (P = 0.02). During the postoperative period heart rate and blood pressure were significantly decreased in clonidine treated patients (P < 0.05). We conclude that clonidine effectively prevents agitation after sevoflurane anesthesia.

Single-dose dexmedetomidine reduces agitation after sevoflurane anesthesia in children Anesth analg 2004;98:60-3 Desmedetomidine, because of its sedative and analgesic properties, may be useful for the management of emergence agitation after sevoflurane anesthesia (alpha2 agonist) We conclude that a dose of dexmedetomidine 0.3ug/kg administered after induction of anesthesia reduces the postsevoflurane agitation in children and with no adverse effects

Conclusion Emergence agitation may be related to hypoxia, pain, drug effect, rapid emergence, certain procedures, or patient characters Premedication with midazolam seems to be ineffective Balance technique, decrease MAC of insoluble gas Adequate postoperative analgesia