This study will be conducted at Fayoum University Hospital after the approval of the
local institutional ethics committee and local institutional review board. The study
design will be a randomized, double-blind, controlled study. A detailed informed consent
form will be signed by eligible patients prior to enrollment and randomization.
Inclusion criteria:
Anesthesia procedure Patients will be randomly allocated into one of three parallel
groups (37 in each group) based on sample size. Randomization will be achieved using
computer-generated random numbering of each study patient. opaque sealed envelopes will
be used and opened in the operating room by a anesthesia resident who will be blinded to
the study. The patient and researcher who collects the data after the block will be
blinded to the study group. All study outcomes will be evaluated by a dedicated
anesthesiologist who will be blinded to the group allocation. Patients will be randomized
into three groups.
Group (D) patients who will receive caudal block. Group (QL) patients who will receive
posterior quadratus lumborum plane block. Group (C) patients who will not receive any
blocks. Preoperative assessment A preoperative patient visit will be done for medical
history taking, clinical examination, reassurance, and explaining the method of
anesthesia. The study protocol, caudal block, quadratus lumborum plane block and the
numerical pain rating score score will be explained to each patient during the
preanesthetic counselling. The patient's back will be examined to detect any spinal
deformities . Patients will fast for about 6 to 8 hours for solid meals , for 4 hours for
non clear liquids and for 2 hours for clear liquids before surgery.
Intraoperative management Monitoring equipment will be connected to the patients included
pulse oximetry, non-invasive blood pressure monitoring, five-lead electrocardiogram and
capnography. IV access will be established. Patients in the three groups will receive
general anesthesia after 5 minutes of pre oxygenation with 100% O2. Anesthesia will be
induced with intravenous fentanyl 1mcg/kg, propofol 2 mg/kg and atracurium 0.5 mg/kg.
After oral endotracheal intubation, anesthesia will be maintained with isoflurane
(1.2%_1.5%) in oxygen _air mixture and atracurium 0.1mg/kg with interval about 20 min.
Block technique After stabilizing the patient hemodynamics, caudal block or quadratus
lumborum plane block will be performed in the prone position prior to the skin incision
after aseptic preparation of injection area.
Petit between the iliac crest and the costal margin where the trans abdominal muscle is
identified . The transducer is then slid posterior until the trans abdominal muscle
posterior aponeurosis is identified adjacent to Caudal block
The patient is placed in the prone position typically, a linear transducer is sufficient
for the most caudal epidural injection; However, obese patients may require curved
transducer. The Ultrasound transducer of (LOGIQ P7 ultrasound) will be first positioned
transversely on the midline to obtain a transverse view of the sacral hiatus. The two
sacral cornua appear as two hyperechoic structures ,two hyperechoic band structures are
present between the two sacral cornua. The superficial is the sacrococcygeal ligament
(SCL) and the deep is the dorsal surface of the sacrum. The sacral hiatus is a hypoechoic
area between two band-like hyperechoic structures. At this level, the ultrasound probe is
rotated 90 degrees to obtain a longitudinal view of the sacral hiatus. in the
longitudinal view, the block needle will be inserted using the in plane technique .The
block needle can be visualized in real time piercing the SCL entering the hiatus but
cannot be visualized beyond the apex of the hiatus. It is therefore proposed to limit the
extension of the needle tip beyond the tip of the sacral hiatus to 5 mm to avoid
perforating the dura mater, since the distance between the tip of the sacral hiatus and
the tip of the dural sac can be less than 6 mm .After the needle is inserted in the
caudal canal, 20 ml of 0.25% bupivacaine will be injected. Presence of unidirectional
flow, defined as dominant color on color Doppler image, In longitudinal view of sacral
hiatus during injection will be reported to be predictive of successful caudal injection
and comparable treatment outcomes.
Quadratus Lumborum Plane Block The patient is placed in the prone position , under
aseptic conditions with the sterile convex probe is placed in a transverse view at the
triangle of the QL muscle and the middle thoracolumbar fascia. The projected needle path
is advanced in-plane until the needle tip is visualized between the middle thoracolumbar
fascia and the QL muscle .After confirming the location of the needle with 2-3 ml of
saline and then aspiration, 20 ml of 0.25% bupivacaine is injected in this plane with
confirmation by visualizing hydro dissection . the procedure is applied to the opposite
side using the same dose to achieve bilateral block.
Maintenance and recovery Inadequate analgesia that is predicted by increase of heart rate
or mean arterial blood pressure by more than 20% of baseline will be managed by 0.5mcg/Kg
of fentanyl. Total IV consumption of fentanyl will be recorded. All patients will receive
4mg ondansetron and 1 g paracetamol intravenously 30 minutes before the end of the
operation. At the end of surgery, all patients will undergo reversal of muscle relaxation
with neostigmine 0.05 mg/kg and atropine 0.01 mg/kg.
After recovery from anesthesia, patients will be transferred to recovery room where heart
rate, respiratory rate, saturation and systolic, diastolic and mean arterial blood
pressure will be monitored. Quality of analgesia will be assessed using numerical pain
rating scale (NPRS) Assessment will be performed at admission to the recovery room, 1 h,
2 h, 4 h, 6 h, 8 h, 12 h, 18 h, and 24 h postoperative. Rescue analgesia in the form of
pethidine 0.5 mg/kg will be administered if is pain moderate to severe according to
NPRS≥4 . Time to the 1st rescue analgesic request is recorded.
Also intraoperative or postoperative complications will be recorded such as local
anesthetic toxicity, hypotension, nausea, vomiting as well as neurologic complications
such as weakness, numbness or any neurological deficits. Also operative time will be
recorded.
