Our or penetrated the peritoneum, the surgeon should

Our prospective
single-blinded randomized controlled clinical trial was carried out in the department of

Obstetrics and
Gynecology Faculty of medicine, Zagazig University after approval by the Ethics

Committee of  Zagazig University. A
written informed consent was provided by all participants.  

Inclusion
criteria include women scheduled for gynecological
laparoscopic intervention and more than 18 years
old and over. Women with chronic pain syndrome,
allergy to local anesthetic, postoperative intraperitoneal drain and needed alteration
to laparotomy were excluded from the study. 
Consenting eligible women were randomly allocated to either
laparoscopic-guided transversus abdominis plane block or trocar site local
anesthetic infiltration. The randomization was created by the computer; the allocation was concealed in opaque, sealed and
serially numbered envelopes. Patients and postoperative assistants were blinded
to the procedure, while surgeons and anesthetists were not.

 

For
laparoscopic-guided transversus abdominis plane block group, at the end of the
procedure and before release of pneumoperitoneum, laparoscopic
camera allowed direct internal visualization of
the selected area, between the iliac crest and the costal margin in the
midaxillary line, where the TAP block will be inserted. The surgeon introduced
a needle through the skin and felt the 2-pops
representing the 2 fascial planes. Visualization helped the surgeon to reach
the proper space between the internal oblique and transversus abdominis
muscles. If the needle tip exceeded the
transversus abdominis muscle and was directly beyond or penetrated the peritoneum, the surgeon should withdraw it back 3-5
millimeters to be in the correct place. 20-25 ml of
0.25% bupivacaine with epinephrine was injected on each side after an initial negative aspiration. After completing
injection a bulge was demonstrated owing to pooling of the local anesthetic behind transversus abdominis muscles and
the peritoneum.

 

For trocar site
local anesthetic infiltration group, 10 ml of 0.25%
bupivacaine with epinephrine was injected around the opening of the umbilical
port. 5ml was injected around each one of the essential two and the extra 5mm
laparoscopic port openings at the end of the procedure.   

 

Demographic and
preoperative data like age, body mass index (BMI), type of operation and the
total operative time were collected. During surgery
all patients received the same intravenous analgesia according to body weight
(fentanyl 1.5 mcg /kg) by the anesthesiologist. They
did not receive analgesics immediately after surgery in the post anesthesia
care unit till complete recovery. In the postoperative ward they received the standard post-operative analgesics.  Our department protocol
is 1gm intravenous paracetamol every 8 hours and intravenous meperidine 20 mg
every time the patients need analgesia.  Postoperative pain was assessed at 1, 3, 6, 12, 18 and 24hours with
a 10 points visual analogue scale (VAS), with a range of 0 (indicating
no pain) to 10 (indicating the worst pain). The cumulative
meperidine consumed on request was calculated
at 3, 6, 12, and
24hours. Patient satisfaction was reported
on a scale from 0 (indicating very poor satisfaction) and 10 (indicating
excellent satisfaction) at 24 hours. 

 

The primary outcome was the difference in pain scores at 1, 3, 6,
12, 18 and 24hours between the two groups. The
secondary outcomes were the differences in the cumulative meperidine
consumed at 3, 6, 12, and 24hours, in addition to the difference in patient
satisfaction at 24 hours between the two groups.

  

Sample size calculation was based on a previous suggestion
that two points difference in VAS between the two groups would be clinically
expressive 9. With a suggested standard deviation of difference to be 4, each
group should contain 34 women to provide this
difference with 80% power and statistical significance of 0.05.  We added five women to compensate for an
assumed 15% dropout, so at least 39 women should be included in each group.