The Effect and Safety of the Four Points Transversus Abdominis Plane Block
Condition: Liver Diseases; Adult Disease
MeSH terms: Liver Diseases
Study type: Interventional

Summary: 
      The anterior abdominal wall from below the xiphoid to infraumbilical area is dominated by the
      sensory nerves which originate from the anterior rami of the thoracolumbar spinal nerves from
      T6-L1. The branches nerves from T7-T12 are between aponeurosis internal oblique and
      transversus abdominal muscle. They can be approached with the ultrasound guidance at
      subcostal and lateral abdominal wall position.

      The bilateral transversus abdominis plane (TAP) block has been demonstrated effectiveness and
      safety in postoperative analgesia to the under abdominal surgery. However, the effect of one
      to the upper abdominal surgery is unclear.

      The four points TAP block has been described the first in 2010. The effect of the four points
      TAP block in postoperative analgesia to the upper abdominal surgery has been reported in
      recent years. Besides, the effect of thoracic paravertebral block (PVB) in postoperative
      analgesia to liver resection was also reported. The both techniques have been performing in
      some studies. The effect and safety of the both techniques have been reported. However, the
      evidence level is still weak. The investigators need to find a technique, which has
      effectiveness as well as safety to replace the epidural analgesia, which was confirmed that
      had many complications, in postoperative analgesia to the hepatectomy.

      The investigators hypothesized that the four points TAP block under the ultrasound guidance
      has more effectiveness than the thoracic paravertebral block in postoperative analgesia to
      the hepatectomy.
    

Detailed description: 
      This is a randomized, controlled, no blind, clinical trial. The study was approved by Board
      of Scientists and Ethic Council in Gia Dinh People Hospital on May 28, 2018. The written
      informed consent will be obtained from all subjects participating in the trial. The trial
      will be registered prior to patient enrollment at Gia Dinh People Hospital.

      The investigators will select 60 participants who are selective hepatectomy with the
      "J-shape" incision, II-III of Anesthesiologists Society America (ASA), from 18-75 age. The
      cases have chronic pain, tolerance opioids, psychology disorder, and allergy opioids or
      ropivacaine will excluded. All of participants will be randomly divided two groups. There are
      TAP group and PVB group. Each one has 30 cases.

      General anesthesia:

      All of cases will be examined, prepared, supplied the study's information on the day before
      surgical date. The cases, who have enough selective standard, will be selected.

      In the operating room, the participants will be performed general anesthesia The participants
      will be started anesthesia with 1 mg of midazolam, 0.3 mcg/kg of sufentanil, 1-1.5 mg/kg of
      propofol, and 0.6 mg/kg of rocuronium. Then, the participants will be maintained anesthesia
      with sevoflurane, sufentanil, and rocuronium. The end of surgery, they will be prevented
      postoperative nausea and vomiting with 4 mg of ondansetron; and reversed residual of muscle
      relaxant with sugammadex.

      Approaching the transversus abdominal plane:

      The technique will be performed at the end of surgery. The TAP group will be performed the
      four points TAP block under the ultrasound guidance with the ultrasound machine of Logiq E,
      and linear 12S probe. The participants will be performed TAP block at subcostal and lateral
      abdominal wall at right and left side with stimuplex needle (sized 18G, length 100 mm). The
      investigators will approach position between aponeurosis internal oblique and transversus
      abdominal muscle with in-plane real-time ultrasound technique. The investigators will inject
      10 ml of ropivacaine 0.375% at each one. Then, the investigators will access one catheter at
      TAP at right side to continuously infuse ropivacaine 0.375% during 48 hours after surgery.

      Approaching the thoracic paravertebral space:

      The investigators will access one catheter into the right thoracic paravertebral space at T7
      before beginning general anesthesia. At the end of surgery, we will inject 20 ml of
      ropivacaine 0.5% through catheter, and continuously infuse ropivacaine 0.25% during 48 hours
      after surgery.

      Patients-controlled analgesia (PCA):

      All of participants will be treated postoperative analgesia with sufentanil during 48 hours
      after operating. The sufentanil will be injected 2 mcg to patients before awaking. Then, the
      participants will be intravenously infused with PCA (2 mcg of single dosage, 6 minutes of
      lockout time, and 8 mcg/hour of limited dosage).

      The both groups will be intravenously injected 0.2 mg/kg of ketamine at the pre-incisional
      and post-incisional. After operating, they will be taken 325 mg of paracetamol plus 37.5 mg
      of tramadol (ultracet tablet) every 8 hours.

      Outcomes:

      The primary outcome is the consumption of sufentanil (mcg) during 24 hours after operating.
      The secondary outcomes are the complications of technique, systemic toxicity of ropivacaine,
      side-effect of sufentanil, and satisfaction of participants.

      The complications of the four points TAP block include hematoma in abdominal wall, and
      puncturing peritoneum. The complications of the thoracic paravertebral block include
      pneumothorax, and injecting vascular. The hematoma in abdominal wall, puncturing peritoneum,
      injecting vascular will be observed and recorded by one other anesthesiologist who has not
      attend the study. The pneumothorax will be diagnosed with the ultrasound by one doctor who is
      educated the general ultrasound. The systemic toxicity of ropivacaine include central nervous
      system (CNS) toxicity and cardiovascular toxicity. The signs and symptoms of CNS toxicity
      include tinnitus, disorientation, and ultimately, seizures. The signs and symptoms of
      cardiovascular toxicity include hypotension, dysrhythmias, and cardiac arrest. The
      complications will be treated depending on severity follow the protocol when they occured.
      The side-effect of sufentanil include sedation, dyspnea, pruritus, and nausea and vomiting.
      The sedation will be evaluated follow Ramsay scale. The dyspnea is decreasing oxygen
      saturation by pulse oximetry (SpO2) <= 92%, frequence <= 8 breaths/minute. The satisfaction
      will be measured follow visual analogue scale (VAS). The VAS scale has from 0 to 10,
      equivalent to the zero is complete dissatisfaction and the ten is highly satisfaction.

      Data processing:

      The investigators will process data with SPSS 25.0 (Reg No: 1975-01566-C). The consumption of
      sufentanil and satisfaction variables will be described by mean (SD) if it is standard
      distribution, or by median (CI 95%) if it isn't standard distribution. The variables of both
      groups will be compared by the independent T test or Mann-Whitney test. The quantitive
      variables will be described by frequency (percentage rate). The investigators will be
      compared by Chi-square test or exact's Fisher test. The sample size is calculated with 90% of
      power, and 20% of difference of the consumption of sufentanil of both groups, and 10% of
      cases losing. The alpha error is 0.05.
    

Intervention name(s): TAP; PVB; Ropivacaine; Sufentanil
Intervention type(s): Procedure; Procedure; Drug; Drug
Intervention description(s): The TAP group will be performed at four points at abdominis plane with ropivacaine 0.375%; The PVB group will be performed at paravertebral space T7 with ropivacaine 0.5%; Ropivacaine has been treated the both group; Sufentanil has been included in Arm/Group Descriptions
Other intervention name(s): The four points TAP block; The paravertebral block; have not been specified; Sufentanil PCA
Intervention MeSH terms: Sufentanil; Dsuvia; Ropivacaine
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: The TAP group will be performed the four points TAP block under the ultrasound guidance with the ultrasound machine of Logiq E, and linear 12S probe. The participants will be performed TAP block at subcostal and lateral abdominal wall at right and left side with stimuplex needle (sized 18G, length 100 mm). The investigators will approach position between aponeurosis internal oblique and transversus abdominal muscle with in-plane real-time ultrasound technique. The investigators will inject 10 ml of ropivacaine 0.375% at each one. Then, the investigators will access one catheter at TAP at right side to continuously infuse ropivacaine 0.375% during 48 hours after surgery.
PVB group: the investigators will access one catheter into the right thoracic paravertebral space at T7 before beginning general anesthesia. At the end of surgery, the investigators will inject 20 ml of ropivacaine 0.5% through catheter, and continuously infuse ropivacaine 0.25% during 48 hours after surgery.
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Hepatectomy; Transversus abdominis plane block (TAP block); Paravertebral block; Postoperative analgesia; Liver resection