Caudal Block for Postoperative Analgesia
Conditions
Keywords
Caudal block, Intracranial pressure, Propofol, Sevoflurane, Ultrasound
Brief summary
Caudal block is commonly used for postoperative analgesia in paediatric patients. A higher volume (1.5 ml/kg) of local anaesthetic for caudal block has been reported to not only increase the level of cranial spread but also provide better quality and longer duration of analgesia in comparison with the conventional volume (1.0 ml/kg). However, caudal block with a high volume of local anaesthetic can increase intracranial pressure (ICP). Previous studies have shown that propofol anesthesia lowers ICP when compared with volatile anesthesia. Therefore, this study was designed to test if propofol can reduce the magnitude of ICP increase following caudal block when compared with a volatile anesthetic, sevoflurane. There is increasing evidence that optic nerve sheath diameter (ONSD) measured by ultrasonography correlates with degree of ICP and is able to detect intracranial hypertension. Therefore, ONSD will be measured as a surrogate of ICP.
Detailed description
Equal number of patients are randomly assigned to the P or S group. The participants in the P and S group are anesthetized with propofol and sevoflurane, respectively. Irrespective of assigned group, all participants receive caudal block with 1.5 ml/kg of 0.15% ropivacaine (up to 30 ml per individual participant). All anesthetic procedures except for main anesthetic agent are the same in all participants. ONSD is measured at the following time points: before (T0), immediately after (T1), and 10 min (T2) and 30 min(T3) after caudal block. Two measurements of each optic nerve sheath are acquired in each eye. The mean value of the four measurements is considered as the ONSD at each time point.
Interventions
DRUGPropofol
The participants in the group P are anesthetized with propofol
DRUGSevoflurane
The participants in the group S are anesthetized with sevoflurane.
Sponsors
Yonsei University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
SINGLE (Outcomes Assessor)
Masking description
Anesthesia machine and infusion pumps are shielded from assessors who measure ONSD.
Intervention model description
There are 2 groups according to the type of main anesthetic agent. P group are anesthetized with propofol, so are S group with sevoflurane.
Eligibility
Sex/Gender
ALL
Age
3 Years to 5 Years
Healthy volunteers
No
Inclusion criteria
* Among children undergoing urological surgery, patients, 36 to 72-months-old * Body weight less than 20 kg (The limit on body weight is set because the maximum volume of local anaesthetic for caudal block in children is restricted to 30 ml.) * Treatment plan for caudal block for analgesia, are enrolled.
Exclusion criteria
* Symptoms or signs of spinal anomalies or infection at the sacral region * Coagulopathy * Increased ICP * Ophthalmic diseases * History of increased ICP
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| ONSD | before (T0) caudal block. | ONSD is a surrogate for ICP. ONSD was measured by transorbital sonography. Transorbital sonography is performed using a linear 6-13 Hz probe. After applying a thick layer of sterile coupling gel on the closed upper eyelid, the probe is placed gently without exerting pressure. Axial images of the orbit are acquired in the plane of the optic nerve, and ONSD is measured 3mm posterior to the optic nerve head as described previously. |
Secondary
| Measure | Time frame |
|---|---|
| The variables affecting ICP : Mean arterial pressure (mmHg) | before (T0) caudal block. |
| The variables affecting ICP : End-tidal carbon dioxide partial pressure (mmHg) | before (T0) caudal block. |
| The variables affecting ICP : End-tidal sevoflurane concentration (volume %) | before (T0) caudal block. |
| The variables affecting ICP : Heart rate (beats per minute) | before (T0) caudal block. |
| The variables affecting ICP : Body temperature (℃) | before (T0) caudal block. |
| The variables affecting ICP : Peak inspiratory pressure (mmHg) | before (T0) caudal block. |
| The variables affecting ICP : Estimated propofol effect-site concentration (μg/ml) | before (T0) caudal block. |
Countries
South Korea
Outcome results
None listed