Analgesic Effects of Caudal S-ketamine for Supplementation of Ropivacaine Caudal Analgesia in Children With Hypospadias

Tao Zhang44 enrolled

Overview

Caudal analgesia with ropivacaine is commonly used in sub-umbilical pediatric surgery. However, increasing the dosage of ropivacaine has not been found to prolong the action significantly while complications will be serious. Ketamine as an additive to caudal administration had been shown to prolong the duration of postoperative analgesia, while the analgesic effectiveness of S-ketamine, the S(+)-enantiomer of ketamine with less possibility to induce psychomotor disturbances, is not clear. In this prospective randomized double-blind clinical trial , the investigators aimed to study the effect of S-ketamine as additive on the duration of caudal analgesia.

Forty-four children scheduled for hypospadias randomize into 2 groups. Group E (n=22) (0.2% ropivacaine 0.7 ml／kg and S-ketamine 0.5 mg/kg), group C(n=22)( 0.2%ropivacaine 0.7ml／kg and equivalent saline) intraoperative and postoperative hemodynamics will be recorded. Postoperative pain is assessed using an established 6-item FLACC score at 1h,3h,6h,12h,24h,48h, or the time when children complain of pain after surgery. A score of more15μg/kg is administered.Investigators propose to compare the duration of caudal analgesia provided by plain ropivacaine and by a mixture of ropivacaine and S-ketamine.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Enrollment

Conditions

Postoperative Analgesia

Interventions

S-ketamine & RopivacaineDRUG

The experiment group (Group E) will receive a mixture of ropivacaine 0.2% 0.7 ml／kg and preservative-free S-ketamine 0.5 mg/kg caudally for postoperative analgesia.

RopivacaineDRUG

The experiment group (Group C) will receive ropivacaine 0.2% 0.7 ml／kg plain and equial volume saline caudally for postoperative analgesia.

Eligibility

Sex: MALEMin age: 3 MonthsMax age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * informed parent consent, ASA I or II children, between 3months and 18 years of age,and weighing \<28kg, scheduled for elective hypospadias surgery with general anesthesia will be recruited. Exclusion Criteria: * Patients who have congenital abnormalities of lower spine and meninges. * Patients with hypersensitivity to any local anesthetics * Children with coagulation disorders * Presence of Infections at puncture sites * Preexisting neurological disease * Refusal to consent by parent/guardian

Outcomes

Primary Outcomes

duration of caudal analgesia

Duration of analgesia is defined as the time from caudal injection to the first need for systemic analgesia.

Time frame: 48 hours after the caudal injection

Secondary Outcomes

morphine consumption

The Face, Legs, Activity, Cry, and Consolability (FLACC) scale at 1 hour (h), 3h,6h,12h,24h,48h or the time when children complain of pain after surgery. A score of more than 3 points is taken as an indication of inadequate analgesia and morphine 15ug/kg was administered .

Time frame: 48 hours after caudal block

FLACC score

The Face, Legs, Activity, Cry, and Consolability (FLACC) scale

Time frame: 48 hours after the caudal block

complication

the incidence of residual motor block, urinary retention, paraesthesia; the incidence of respiratory depression ,vomiting ,nystagmus ,pruritus，odd behavior;.the sedation scores etc.