|Year : 2015 | Volume
| Issue : 1 | Page : 100-106
Ultrasound-guided rectus sheath block versus local infiltration in management of pain after single-incision laparoscopic cholecystectomy
Ayman A Kasem MD , Ashraf A AbdelKader
Department of Anesthesia, Ain Shams University, Cairo, Egypt
|Date of Submission||27-May-2014|
|Date of Acceptance||19-Oct-2014|
|Date of Web Publication||25-Mar-2015|
Ayman A Kasem
Ain Shams University Hospitals, Cairo
Source of Support: None, Conflict of Interest: None
Single-incision laparoscopic cholecystectomy (SILC) allows decreasing the number of incisions and tissue trauma. Efforts have been made to decrease port incision pain, as it constitutes up to 70% of postoperative pain. Rectus sheath block provides effective analgesia to the midline.
The aim of the study was to evaluate the efficacy of ultrasound (U/S)-guided rectus sheath block for pain management following SILC surgery.
Patients and methods
A total of 50 patients undergoing elective SILC were allocated randomly into two groups: U/S-guided rectus sheath block, the R group, or local infiltration, the L group. All patients received the same general anesthetic technique. In the L group, port-site infiltration was made by the surgeon using 0.5% bupivacaine. In the R group, bilateral U/S-guided rectus sheath block was performed using 10 ml of 0.5% bupivacaine. Total fentanyl amount received intraoperatively was recorded. Patient Controlled Analgesia (PCA) morphine was used for postoperative analgesia and the morphine consumption was recorded. Lornoxicam was given as rescue analgesia and its time was recorded. Pain was measured by visual analogue score. Sedation score (from 0 awake to 5 unarousable) was used. Any adverse events were recorded.
In all, 45 patients completed the study. Total amount of fentanyl was not different and no adverse events were reported. The number of patients who received rescue analgesia was not different. In addition, neither PCA start time nor PCA morphine consumption was different, whereas the total PCA morphine use in 24 h was lower in the R group.
U/S-guided rectus sheath block is an effective analgesic technique with morphine-sparing effect after SILC surgeries.
Keywords: laparoscopic cholecystectomy; local infiltration; rectus sheath
|How to cite this article:|
Kasem AA, AbdelKader AA. Ultrasound-guided rectus sheath block versus local infiltration in management of pain after single-incision laparoscopic cholecystectomy. Ain-Shams J Anaesthesiol 2015;8:100-6
|How to cite this URL:|
Kasem AA, AbdelKader AA. Ultrasound-guided rectus sheath block versus local infiltration in management of pain after single-incision laparoscopic cholecystectomy. Ain-Shams J Anaesthesiol [serial online] 2015 [cited 2021 May 6];8:100-6. Available from: http://www.asja.eg.net/text.asp?2015/8/1/100/153950
| Introduction|| |
Laparoscopic cholecystectomy was reported for the first time by Erich Muhe in 1985. Because of its significant advantages in reduction of postoperative pain, shortening of hospital stay, and earlier return to normal function, it became the gold-standard procedure for cholecystectomy  .
Over the last 20 years, many laparoscopic surgeons worked to decrease wound size and number of incisions. This led to innovative technique of single-incision laparoscopic cholecystectomy (SILC) surgery and has met a favorable acceptance in surgical community. Its feasibility and safety have been proved in a number of surgical procedures including cholecystectomy  . It was reported for the first time by Navarra et al.  . Since that time, it became popular and several studies examined its feasibility, safety, and advantages in selected patients  .
There are three main sources for pain after laparoscopic cholecystectomy: the incision sites, the pneumoperitoneum [due to (a) local changes (peritoneal and diaphragmatic stretching) and (b) systemic changes (exaggeration of the local tissue inflammatory response)], and the gall bladder surgical bed in the liver after cholecystectomy. The largest component of abdominal pain is the incisional pain (50-70%), which is usually mild to moderate in intensity, and maximal immediately postoperatively, subsiding with time, followed by the pneumoperitoneum (20-30%) and cholecystectomy bed (10-20%)  . Shoulder pain is a referred pain from pneumoperitoneum and is often mild in intensity on the first day, increasing and being significant in the following day and can remain up to 3 days  .
As incisional site contributes for up to 70% of pain after laparoscopic cholecystectomy, many studies have been conducted to deal with incisional site pain. Peripheral use of local anesthetics for postoperative pain relief is an attractive method and port-site infiltration in laparoscopic cholecystectomy at the end of surgery was found to decrease postoperative pain significantly. Unfortunately, such effect was described as short-term benefit and was limited by the duration of local anesthetic action , .
The rectus sheath block was described for the first time in 1899 by Schleich and was initially used to achieve relaxation of abdominal wall muscles during laparotomy before the adjunct of neuromuscular block. This technique aims to block the terminal branches of intercostal nerves that are located in the space between the rectus abdominis muscle and its posterior rectus sheath resulting in anesthesia of the midline. In 1996, Ferguson and colleagues suggested a rectus sheath block to provide analgesia for umbilical hernia repair in children. Since then, this regional anesthetic technique has become increasingly popular and is used to provide analgesia for umbilical and epigastric hernia repair, pyloromyotomy, and other small midline incisions , .
Ultrasound (U/S) guidance allows for a greater reliability in administering local anesthetic in the correct plane and decreasing the remote potential for complications. Guiding the needle under U/S guidance to the posterior rectus sheath rather than relying on 'pops', such as in the traditional, non-U/S techniques, makes this block more reproducible and reduces the risk for inadvertent peritoneal and vascular punctures  .
As local anesthetic in rectus sheath block is deposited in a closed space, it is expected that the duration of action will be prolonged. Unfortunately, the reported duration of analgesia was limited to few hours as it was performed on day surgery cases  .
The aim of this study was to evaluate the efficacy of U/S-guided rectus sheath block in comparison with the conventional local port infiltration for management of the postoperative abdominal pain following SILC surgery.
| Patients and methods|| |
This study was conducted in King Abdul-Aziz Airbase Hospital, Dhahran, Kingdom of Saudi Arabia. The procedure for this study was approved by the Ethics Committee of the hospital. All patients gave written informed consent. Fifty adult ASA physical status I or II patients of both sexes undergoing elective SILC were included in this study. Exclusion criteria included age below 18 years or more than 60 years, allergy to amide local anesthetic, chronic pain diseases other than gallstone disease, or a history of psychiatric disease, alcohol, drug abuse, and operation for acute cholecystitis.
Patients are allocated randomly by a computer-generated list into two groups: the U/S-guided rectus sheath block (R) group or the local infiltration (L) group. All patients received the same general anesthetic technique. No premedication was used. General anesthesia was induced with intravenous fentanyl (2 µg/kg) and propofol (2.0-2.5 mg/kg). Tracheal intubation was facilitated by cisatracurium (0.15 mg/kg). Anesthesia was maintained with oxygen in N 2 O and sevoflurane. All patients were mechanically ventilated with pressure-controlled mode with targeted EtCO 2 (30-35 mmHg). All patients received 4 mg ondansetron intravenously near the end of the surgery. Standard monitoring maintained throughout the procedure included ECG, noninvasive arterial pressure, arterial oxygen saturation, and capnometry.
In the local infiltration (L) group, subcutaneous infiltration at port site (supraumbilical) was made by the surgeon using 0.5% bupivacaine. After skin incision, the fascia, muscle, preperitoneal space, and the parietal peritoneum were also infiltrated. A maximum bupivacaine dose of 2 mg/kg was not exceeded.
In the rectus block (R) group, the skin was disinfected and a high-frequency linear array transducer 6-13 mHz was connected to portable U/S machine (M-Turbo; SonoSite, Bothell, Washington, USA) placed immediately lateral to the planned incision, in a transverse position ([Figure 1]), then the probe was rotated to a longitudinal position ([Figure 2]). The needle (22 G, L 85 mm; Visioplex, Vygon, France) was inserted in-plane in a cephalad to caudad orientation, through the subcutaneous tissue, to pierce through the anterior rectus sheath. The needle was further advanced through the body of the muscle until the tip rests on the posterior rectus sheath. After negative aspiration, 1-2 ml of 0.9% saline was injected to verify needle tip location. When injection of the local anesthetic appears to be intramuscular, the needle was advanced 1-2 mm and its position was checked by injection of another amount of 0.9% saline (hydrodissection). This was repeated until the correct needle position was achieved. In an adult patient, 10 ml of 0.5% bupivacaine per side is usually sufficient for successful blockade.
Vital data were recorded after 5 min from the tracheal intubation as a baseline. If there was an increase in heart rate, noninvasive arterial pressure, or both by more than 15% relative to the baseline measurements, fentanyl 0.2 µg/kg was administered. The total amount of fentanyl received during the operation was recorded.
Postoperative analgesia was given in the form of PCA morphine, 1 mg dose, lockout time 10 min, 10 mg 1 h limit (GemStar; Hospira Inc., Houston, Texas, USA). Patients were educated on the use of PCA pump during preoperative anesthesia clinic visit. The time to the first dose of morphine administered by PCA (first button press), the amount of morphine consumed during the early postoperative period (first 3 h), and the total morphine use until shifting to oral analgesics were recorded. Lornoxicam (Xefo 8 mg; Nycomed, Baylis Road, Melville, NY) intravenous was given as a rescue analgesia, in case patients required analgesia before starting PCA morphine, and the time of that rescue analgesia was recorded. Ondansetron (4 mg) intravenous was given in case of postoperative nausea and vomiting.
The severity of pain was measured by visual analogue score in the recovery room and at 2-4, 6-8, 10-12, and 18-24 h after operation and was recorded (if the patient was asleep at the measurement time, the visual analogue score was considered as 0). Sedation score (from 0 awake to 5 unarousable) was recorded at discharge from recovery room to the ward and at 6, 12, and 24 h.
Postoperative nausea and vomiting together with the amount of antiemetic medications received during the first 24 h were recorded. Any adverse events including bleeding, swelling, or bruising related to the technique used were also recorded in both groups.
Statistical data analysis
Using PASS (North 1000 East, Kaysville, Utah 84037, USA) for sample size calculation, it was calculated that a sample size of 24 per group will achieve 80% power to detect a difference of 50% in analgesic requirements at the first 24 h postoperative between the two groups with a significance level (α) of 0.05 using a two-sided two-sample t-test; 25 patients per group were included to replace any dropouts.
The statistical analysis was performed using a standard SPSS software package, version 17 (SPSS Inc., Chicago, Illinois, USA). Data were expressed as mean values ± SD and numbers (%). Student's t-test was used to analyze the parametric data, and discrete (categorical) variables were analyzed using the χ2 -test; nonparametric data were compared using the Mann-Whitney test, with P-values less than 0.05 considered statistically significant.
The primary outcome of this study was the percentage of morphine-sparing effect, whereas associated nausea, vomiting, itching, and sedation were the secondary outcomes.
| Results|| |
A total of 50 patients were included in this study; five were excluded due to conversion to either conventional laparoscopic surgery, three patients (one in the R group and two in the L group), or open cholecystectomy, two patients (one in each group) ([Figure 3]).
There were no significant differences between the R and the L groups with respect to the total amount of fentanyl consumption intraoperatively (168 ± 28 and 174 ± 36 μg, respectively).
There were no reported cases of bleeding, swelling, or bruising at the injection site in both groups. In addition, there were no recorded episodes of deep sedation that required antidote medications or removal of the PCA button. There was no difference in the total amount of the antiemetic medications received in both groups or in the number of episodes of nausea and vomiting.
In the first 3 h postoperatively, the number of patients who received lornoxicam (8 mg) intravenously was not significantly different between the two groups, five versus three patients in the L and R groups, respectively. In addition, neither PCA start time nor PCA morphine consumption during that period was different in the study groups [66 vs. 70 min and 1.2 (±0.5) mg vs. 1.1 (±0.3) mg in the L and R groups, respectively], whereas the total PCA morphine use in the first 24 h was significantly lower in the R group compared with the L group [10 (±2.5) mg vs. 17 (±4.5) mg, respectively] ([Table 1] [Table 2] [Table 3] [Table 4]).
| Discussion|| |
Laparoscopic cholecystectomy became one of the most frequently performed procedures in visceral surgery. Early postoperative pain after laparoscopic procedures is a frequent complaint, although it is usually associated with decreased surgical trauma response and shortened convalescence. Current efforts focus on minimizing trauma and improving cosmoses by reduction of number of the inserted trocars. The appearance of single-port laparoscopic surgeries in the recent years continues this trend. SILC can offer better cosmetic outcome, reduced postoperative pain due to less operative trauma, less complications, and rapid recovery. However, the superiority of the SILC compared with the conventional laparoscopic cholecystectomy (CLC) is still controversial  .
Postoperative pain after SILC compared with CLC is controversial; published studies have suggested that patients undergoing SILC had higher pain score and greater amount of analgesic requirement within the first day postoperative when compared with patients undergoing CLC. This may be due to the wider fasciotomy of the transumbilical incision, the vigorous manipulation needed to place the wound retractor when the fasciotomy is insufficient, and/or increasing operative time resulting in prolonged stretching and umbilical wound ischemia by single multichannel port , . In 2012, Kim et al.  found that pain scores measured 24 h after operation were significantly higher in patients who had received single-port appendectomy than those of the patients who had received conventional laparoscopic appendectomy. In contrast, recently published studies have suggested that patients undergoing SILC had similar pain score and total amount of analgesic requirement within 24 h after operation when compared with CLC , .
Peripheral use of the local anesthetics includes various routes of administration such as intraperitoneal instillation and port-site infiltration. They have been tried in different concentrations and volumes to study their efficacy in pain control after laparoscopic surgeries. Several studies evaluating its efficacy in laparoscopic cholecystectomy have been published worldwide. Although in many of these studies a significant reduction in postoperative pain score after intraperitoneal instillation of local anesthetics has been reported, others have reported no benefit. Majority of the studies were in favor of local anesthetics, mainly during the early postoperative period, that they decrease the total opioid consumption during the postoperative period. However, they have not been found to be effective during late postoperative period and they cannot be used as a single agent for pain management after laparoscopic cholecystectomy  .
Transversus abdominis plane (TAP) block relies on guiding the needle with U/S to the plane between the transversus abdominis and internal oblique muscles, to block the anterior rami of the lower six thoracic nerves (T7-T12) and the first lumbar nerve (L1). Injection of local anesthetic within the TAP potentially can provide unilateral analgesia to the skin, muscles, and parietal peritoneum of the anterior abdominal wall from T7 to L1, although in clinical practice, the extent of the block is variable  . It has been performed for pain relief in cesarean section , , bowel surgery  , retropubic prostatectomy  , and laparoscopic surgery ,,,,, .
Mixed results were found regarding the application of TAP blocks in laproscopic surgery. El-Dawlatly et al.  reported substantially reduced perioperative and postoperative opioid consumption in patients undergoing laparoscopic cholecystectomy who received an U/S-guided TAP block compared with those who did not. In addition, Hosgood et al.  showed TAP block to be beneficial in patients undergoing laparoscopic live-donor nephrectomy. In contrast, Sandeman and et al.  found TAP block to be equally effective in patients undergoing laparoscopic appendectomy compared with those who received local anesthetic port-site infiltration. Most recently, Petersen et al.  showed only a minor nonsignificant benefit in patients undergoing laparoscopic cholecystectomy who received TAP block compared with those who received placebo blocks.
Although U/S-guided rectus sheath block is now used to provide effective pain relief for umbilical and epigastric hernia repair, pyloromyotomy, and other small midline incisions  , its efficacy has not yet been tested in laparoscopic surgery. An old study by Smith et al.  found that pain after diagnostic laparoscopy can be significantly reduced by bilateral rectus sheath block by relying on 'pops' in the traditional, non-U/S technique and injection of 15 ml of bupivacaine (0.25) in each side. However, to the best of our knowledge, U/S-guided rectus sheath block has not been evaluated in laparoscopic surgery yet.
The results of this study showed that U/S-guided rectus block is an effective technique as part of multimodal analgesia for the management of postoperative pain following SILC.
Total amount of fentayl consumption intraoperatively was not different between the two groups. This was in agreement with the results of Sandeman et al.  . However, El-Dawlatly et al.  reported that 76% of patients in the Transversus Abdominus Plane Block (TAB) group received only the induction dose of sufentanil, whereas all patients in the control group required additional intraoperative sufentanil. This discrepancy can be explained, at least in part, by absence of port infiltration in El-Dawlatly control group, whereas in our study and in Sandeman study, the control group received port infiltration.
In the first 3 h postoperatively, we found that there was no significant difference between the two groups with respect to number of patients who received rescue analgesia. In addition, neither PCA start time nor PCA morphine consumption during that period was different. This was in agreement with the results of Gurnaney et al.  who studied the analgesic efficacy of U/S-guided rectus sheath block versus local anesthetics infiltration for open umbilical hernia repair and reported that there was no significant difference between the two groups with respect to the time of start of rescue analgesia. However, El-Dawlatly et al.  reported that there was a significant statistical difference between the two groups with respect to PCA morphine consumption in the first 2 hpostoperatively observed in the recovery room. In addition, the absence of port infiltration may explain this difference.
Total PCA morphine use in the first 24 h was significantly lower in the rectus sheath block group (morphine-sparing effect). This was in agreement with results of El-Dawlatly et al.  . However, Sandeman et al.  reported that the total dose of PCA morphine consumed in the first 16 h was not different between the groups in their study. In addition, Gurnaney et al.  reported that there was a trend toward statistical significance between the two groups with respect to postoperative opioid consumption; however, their pain assessment was continued until patient discharge from hospital, 2 h.
In this study, the pain scores were similar during the early postoperative period up to 4 h and late at the time interval 18-24 h, whereas there was a significant difference between the study groups at the time intervals 6-8 and 10-12 h. Sandeman et al.  reported that median pain scores were reduced for the TAP group in the recovery room only, but pain scores were similar at all other time intervals. Gurnaney et al.  reported that pain scores at rest and with movement between the study groups did not show a significant difference.
Postoperative sedation score was similar between the study groups at admission to and discharge from recovery room and at 24 h, whereas there was a significant difference between the study groups at 6 and 12 h postoperatively. This may be explained by the consumption of more amount of morphine PCA to manage higher pain score at these time intervals. Sandeman et al.  reported that the sedation scores were different between the two groups in the recovery room only. This may be explained by the consumption of the same doses of opioid intraoperatively, and the total dose of PCA morphine consumption was not different between the groups.
U/S-guided rectus block can be performed by either out-of-plane  or in-plane  technique; however, we choose in-plane technique to visualize the whole needle throughout its course. This is to avoid the reported remote potential for perforation of intraperitoneal structures and epigastric blood vessels with hematoma formation when performing a traditional rectus sheath block , . However, in this study, there were no reported cases of bleeding, swelling, or bruising at the injection site.
| Conclusion|| |
U/S-guided rectus sheath block is as effective analgesic technique as local infiltration of the port sites, with longer duration of action and morphine-sparing effect and less sedation during the postoperative period after SILC surgeries.
| Acknowledgements|| |
Conflicts of interest
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[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3], [Table 4]