الفهرس 
ULTRASOUND GUIDED NERVE BLOCKSOnly 14 pages are availabe for public view
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Abstract
The transversus abdominis plane (TAP) block has been shown to provide effective postoperative analgesia in lower abdominal surgery. Subcostal TAP block has also been proposed as a new technique to provide analgesia for the supraumbilical abdomen. Traditionally, pain relief for these patients is provided by thoracic epidural analgesia or IV opioid analgesia. Although epidural analgesia is currently the “gold standard” for postoperative pain treatment, associated complications and contraindications may limit its use. IV opioid analgesia may cause opioid-related side effects and be associated with inadequate analgesia. Ultrasound guided technique made TAP block more accurate and easier. We compared the analgesic effect between continuous subcostal ultrasounded TAP block and patient controlled thoracic epidural analgesia and patient controlled intravenous opioid analgesia after open abdominal surgeries.
Ninety patients undergoing elective oprn abdominal surgeries were randomized to receive either combined general–subcostal TAP anesthesia (group TAP), combined general–epidural anesthesia (group PCEA), or general anesthesia with intravenous patient controlled analgesia (group PCA), and were analyzed on an intention-to-treat basis.
The peri-operative management was identical in all groups apart from the insertion of subcostal TAP catheters & PCA were applied at the end of surgery in TAP & PCA groups respectively. In Epidural group thoracic epidural was inserted pre-operatively.
In combined general–thoracic epidural anesthesia (group PCEA), After preparation of all requirements of both regional and general anesthesia, thoracic epidural was done under complete aseptic condition while patient at sitting position at interspace T7–T9 midline technique using a18G Touhy needle (B.Braun, Perifix®) using loss of resistance technique, and 20G epidural catheter was inserted cephalad 4-6 cm into the epidural space and then secured.
General anesthesia was induced for all patients with intravenous propofol (1.5–2 mg.kg−1) and fentanyl (1–2 μg.kg−1). Tracheal intubation was done following administration of a non-depolarizing neuromuscular blocking drug (Atracurium 0.5 mg.kg-1). Anesthesia was maintained with Sevoflurane (1-1.5 MAC), non-depolarizing neuromuscular (Atracurium 0.01 mg.kg-1.m-1) & fentanyl (3-5 μg.kg−1.h-1) throughout the operative period. The lungs of the patients were ventilated with oxygen (50-60%) using oxygen air mixture and ventilation was adjusted to achieve a EtCO2 of (35–40 mm Hg). Changes in hemodynamics were continuously monitored by ECG, non-invasive blood pressure, pulse oximetry, and capnography.
In combined general anesthesia– bilateral continuous subcostal TAP block (group TAP), bilateral TAP catheters were inserted in the subcostal transversus abdominis plane guided by ultrasound (HONDA electronic ultra-sound scanner model HS-2100®) at the end of the surgery while patients were still under general anesthesia. Under complete aseptic condition, a curved law frequency (5 MHz) ultrasound probe was placed obliquely on the upper abdominal wall, along the subcostal margin near the midline. After identifying the rectus abdominis muscle, the ultrasound probe was moved laterally along the subcostal margin until the transversus abdominis muscle was identified lying posterior to the rectus muscle. A 16-G, 8-cm Touhy needle was introduced medially in the plane of the ultrasound beam and directed towards the transversus abdominis plane. On entering the neurofascial plane, 10 ml saline 0.9% will be injected to open it. The injectate spreading in the transversus abdominis plane was observed as a dark oval shape. Gentle pressure was used to thread an epidural catheter 6–7 cm into the space created and cut the catheter at the 30-cm mark before attaching a filter that will be taped to the chest wall in the midline. 1 mg.kg−1 bupivacaine 0.375% was injected through each as loading dose. The same procedure also was done on the other side by the same technique and the same dosage.
On emergence from anesthesia, inhalational anesthetic was terminated and the residual muscle relaxant was antagonized with Neostigmine in dose 0.03mg.kg-1 and atropine 0.02 mg.kg-1 then patient was extubated after regaining full consciousness, intact reflexes and adequate muscle power and respiration. Then patient was transferred to the recovery area.
In combined general anesthesia– bilateral continuous subcostal TAP block (group TAP), 1 mg.kg−1 bupivacaine 0.375% was injected through each as loading dose, then the patient was connected to an infusion of 0.25% bupivacaine using an infusion pump. The infusion was started at 5 ml. h-1 and 3 ml top up doses of bupivacaine 0.25% was used if VAS score was > 3.
In combined general–thoracic epidural anesthesia (group PCEA), Patient Controlled Epidural Analgesia (PCEA) was administered using elastometric pump (Accufuser Plus® Cairo Med, code M8015M PCA (A-300)) which was prepared by using 150 ml bupivacaine 0.5% and 150 ml saline. Infusion rate was 8 ml. hr-1, PCEA bolus will be 1 ml/time, lock out 15 min. it will deliver 8 up to 12 ml per hour. If VAS score was > 3, rescue analgesia with 5 mL bolus of PCEA solution was applied without changes in the PCEA settings.
In general anesthesia with post operative PCA group (group PCA), at the end of the operation the patient was connected to an elastometric pump (Accufuser Plus® Cairo Med, code M2015M PCA (A-100)) which was prepared by using 40 mg Nalbufen, 60 mg Ketorolac, and total volume was 100ml. Infusion rate was 2 ml.hr-1, PCA bolus will be 1 ml/time, lock out 15 min. it will deliver 0.8 up to 2.4 mg Nalbufen per hour & lasted in to 2 days. It was connected to a separate peripheral IV access. An adjuvant intravenous Nalbufen 5mg if VAS score was >3.
The total duration of postoperative pain management was planned to be over 48 hours.
Ninety patients were enrolled in the study. Data from 71 patients, 22 from group TAB, 24 from group thoracic epidural and 25 from group PCA were included in the final analysis.
Throughout the observation period (48 hrs) we used VAS to compare between the three groups as regard pain score during rest. Patient in the PCEA group had significantly less pain score & they were more satisfied by their pain therapy when compared with the other 2 groups.
As an observation during the study there was also more satisfaction in group PCEA and group PCA in relieving visceral & somatic pain than group TAB which had no effect on visceral pain.
When comparing between group TAB and group PCEA as regard total rescue dose of bupivacain we found that PCEA group used less amount of exctra bolus bupivacain used and there was more difference between those 2 groups as regard pain control as TAB block didn’t alleviate visceral pain but epidural blocked both somatic and visceral pain.
Also we found that one of the main draw backs of PCA was nausea and vomiting which was more prominent in these groups and there was more need to anti-emetics than the other 2 groups.