• Users Online: 302
  • Print this page
  • Email this page


 
 Table of Contents  
ORIGINAL ARTICLE
Year : 2020  |  Volume : 4  |  Issue : 3  |  Page : 320-325

Analgesic efficacy of continuous subcutaneous presternal bupivacaine infusion vs ultrasound-guided bilateral pectoral nerve block in poststernotomy pain


Department of Anesthesia and Intensive Care, Al-Azhar University, Cairo, Egypt

Date of Submission15-Nov-2019
Date of Decision18-Nov-2019
Date of Acceptance30-Dec-2019
Date of Web Publication2-Oct-2020

Correspondence Address:
MD Mofeed A Abdelmaboud
Department of Anesthesia and Intensive Care, Al-Azhar Faculty of Medicine for Boys, Cairo 12992
Egypt
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/sjamf.sjamf_99_19

Get Permissions

  Abstract 


Background The most common cause of pain after cardiac surgery is median sternotomy. Poor postoperative (PO) pain control has serious effect on pulmonary and cardiovascular systems and induces stress and hyperglycemia. Good PO analgesia helps early recovery and discharge.
Aim The primary aim was to compare analgesic efficacy of continuous presternal bupivacaine infusion and ultrasound-guided bilateral pectoral nerve 2 block (Pec 2). The secondary aim was to evaluate their efficacy in controlling respiratory parameters, duration of PO ventilation, ICU stay, and hospital stay.
Patients and methods A total of 100 patients of American Society of Anesthesiologists status II were randomly divided into group I, which received continuous presternal bupivacaine infusion, and group II, which received ultrasound bilateral Pec 2 block. PO visual analog scale (VAS) was recorded at extubation, 3, 6, 12, 18, and 24 h. Pain severity was divided into four grades: no pain, VAS less than 4; mild, VAS 4–5; moderate, VAS 6–7; and severe, VAS greater than 7. Morphine, bupivacaine consumption (mg), and number of request of analgesia in first PO 24 h and inspiratory flow rate (IFR) (l/min) at extubation, 3, 6, 12, 18, and 24 h were recorded. Arterial blood gas parameters were recorded at extubation, 3, 6, 12, and 24 h. Duration of PO ventilation (min), ICU stay (h), and hospital stay (days) were recorded.
Results PO VAS, pain severity, IFR, and arterial oxygen tension/inspired oxygen fraction (PaO2/FIO2) were significantly higher in group II at all study times. Morphine, bupivacaine consumption, and number of request of analgesia in first PO 24 h were significantly higher in group I. Duration of PO ventilation, ICU stay, and hospital stay were significantly longer in group I.
Conclusion First, Pec 2 block was safe and effective in controlling sternotomy pain with lower VAS and pain severity, less bupivacaine, morphine consumption, and less request of PO analgesia. Second, Pec 2 block showed better IFR and PaO2/FIO2, with shorter duration of PO ventilation, ICU stay, and hospital stay.

Keywords: analgesic efficacy, bilateral pectoral nerve 2 block, continuous pre-sternal bupivacaine infusion, post-sternotomy pain, ultrasound


How to cite this article:
Abdelmaboud MA. Analgesic efficacy of continuous subcutaneous presternal bupivacaine infusion vs ultrasound-guided bilateral pectoral nerve block in poststernotomy pain. Sci J Al-Azhar Med Fac Girls 2020;4:320-5

How to cite this URL:
Abdelmaboud MA. Analgesic efficacy of continuous subcutaneous presternal bupivacaine infusion vs ultrasound-guided bilateral pectoral nerve block in poststernotomy pain. Sci J Al-Azhar Med Fac Girls [serial online] 2020 [cited 2020 Oct 31];4:320-5. Available from: http://www.sjamf.eg.net/text.asp?2020/4/3/320/296967




  Introduction Top


Midline sternotomy for cardiac surgery can be associated with remarkable postoperative (PO) pain and discomfort [1].

Inadequate pain management decreases the capacity to cough with increased risk of atelectasis and delayed recovery. Effective pain control after cardiac surgery allows early weaning from ventilation with early hospital discharge [2]. Parenteral opioids are the most commonly used analgesics in such patients which can cause undesirable adverse effects as nausea and vomiting, sedation, and respiratory depression [3].

Continuous bilateral subcutaneous presternal infusion of local anesthetic through multibore catheters provides a nociceptive block of the anterior branches of intercostal nerves at the lateral margins of the sternum [4].

Traditionally, in Pec 1 block, injection is done between pectoralis major and minor muscles, whereas in Pec 2 block in addition to Pec 1, another injection is done between pectoralis minor and serratus anterior. The technique of administering Pec 2 block after surgery without combination with Pec 1 has been named by the authors as modified Pec 2 (mPec 2) block [5].

Pec 1 block aims to block the medial and lateral pectoral nerves, whereas Pec 2 block aims to block the anterior divisions of the thoracic intercostal nerves from T2 to T6, long thoracic nerve, and thoracodorsal nerve. The anterior divisions of the thoracic intercostal nerves (from T2 to T6) lie at the back between the posterior intercostal membrane and the pleura and run in plane between the intercostal muscles as far as the sternum. The long thoracic nerve (or serratus anterior nerve) arises from C5 to C7 and enters the axilla behind the rest of the brachial plexus and rests on serratus anterior muscle [6].


  Aim Top


The primary outcome was to compare the analgesic efficacy [PO visual analog scale (VAS), severity of pain and morphine and bupivacaine consumption] of continuous presternal bupivacaine infusion and ultrasound (US)-guided bilateral Pec 2 block in controlling poststernotomy pain. The secondary outcome was to evaluate their efficacy in controlling respiratory parameters [PO inspiratory flow rate (IFR), pH, arterial carbon dioxide tension (PaCO2), arterial oxygen tension/inspired oxygen fraction (PaO2/FIO2), PO ventilation duration, and duration of ICU and hospital stay].

Sample size justification

Med Cal version 12.3.0.0 program ‘Ostend’ Belgium was used for sample size calculation, which is a statistical calculator based on confidence interval of 95% and 80% study power with 5% α error. According to a previous study by Kumar et al. [7], it can be relied on in this study, and according to this value, minimal produced sample size of 93 cases was enough to find such difference. Assuming 5% dropout, the sample size was 100 cases, subdivided into two equal groups.


  Patients and methods Top


This prospective randomized controlled study was conducted after approval from Anesthesia and Intensive Care Department, Al-Azhar Faculty of Medicine, and from Local Ethics Committee and taking informed written consent from each patient, It was done at Al-Hussein University Hospital in the period from February 2018 to July 2019.

A total of 100 patients aged 31–60 years of both sexes, with American Society of Anesthesiologists physical status II, who underwent valve surgeries either mitral valve replacement or aortic valve replacement through midline sternotomy under general anesthesia were included in this study.

Exclusion criteria included patients with hemodynamic instability, previous sternotomy, emergency surgery, pre-existing coagulopathy, preoperative poor left ventricular function (ejection fraction <40%), kidney or liver diseases, pre-existing neurological or pulmonary dysfunctions, pre-existing infection at the block site, allergy to local anesthetics, prolonged cardiopulmonary bypass (>120 min), intraoperative inotropic support (dobutamine >5 µg/kg/min or epinephrine infusion >1 µg/min), patients required intra-aortic balloon pump, and patients with prolonged PO ventilation of more than 24 h.

The preoperative routine cardiac medications were continued till the morning of surgery.

Preoperatively, patients were trained to report pain using [7] VAS that marked from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain.

All operations were performed by the same surgical team via median sternotomy.

All patients received injection of fentanyl 3–5 μg/kg with induction of anesthesia for intraoperative analgesia.

After confirming hemodynamic stability, minimal drain output, and satisfactory blood gases and electrolytes, the patients were randomly allocated into two equal groups of 50 patients each by using computer generated randomization numbers, which were concealed in opaque envelopes that were opened after patients’ enrolment. Group I (bupivacaine infusion group) received continuous subcutaneous presternal bupivacaine infusion, whereas group II (Pec group) received US-guided bilateral Pec 2 block.

In group I, after sternal wiring, epidural catheter (Epidural Catheter 20 G; 2675–1 Nishikata, Koshi Gaya-Shi, Saitama, Japan) was positioned anterior to the sternum in the subcutaneous tissue during wound closure. The syringe pump was filled with 0.125 ml bupivacaine (Markyreneo; Depeiky for Pharmaceutical Industries, Zone 11 block 12014 Obour City). The catheter was connected to syringe pump (Injectomat Agilia Fresenius Kabi, Three Corporate Drive, Lake Zurich, Illinois, USA), and then continuous infusion of bupivacaine at a fixed rate of 5 ml/h started at skin closure. The catheter was removed after 24 h.

In group II, bilateral Pec 2 block was done after skin closure under linear US guidance (12 MHz). After complete aseptic condition, Pec 2 block was performed using a 20 G 5 cm needle, with the patient in supine position with the arm slightly abducted. The probe was placed perpendicular to the midpoint of the clavicle along its inferior border and then moved inferolaterally until the pectoralis major, the pectoralis minor, and the serratus anterior muscles were identified at the level of the third and fourth ribs ([Figure 1]). All PEC blocks were done by a single operator with previous experience in the technique (>50 times).
Figure 1 Sonoanatomy of Pec block.

Click here to view


The needle was inserted in-plane with the US probe. A volume of 20 ml of 0.125 bupivacaine was injected in the fascial plane between pectoralis minor and serratus anterior muscle, followed by injection of 10 ml in the fascial plane between pectoralis major and minor muscles. The block was done similarly on the opposite side. Overall, 5 ml of 0.125% bupivacaine was infiltrated in the skin around the mediastinal drain. Attention was taken not to exceed the toxic dose of bupivacaine (3 mg/kg). PEC block failed in three patients, and those patients were excluded from the study and replaced by another three patients.

At the end of surgery, neuromuscular blocker was not antagonized, patients were transferred to the ICU and remained intubated and mechanically ventilated (SIMV mode, respiratory rate 14/ min, I : E ratio 1 : 3, with the lowest FIO2 that keep oxygen saturation >90%) (Drager, Infinity C 300, Drager Medical GmbH Moislinger Allee, Lubeck, Germany).

Patients were extubated once they fulfilled the extubation criteria which included adequate airway reflexes, absence of arrhythmias, hemodynamic stability, acceptable blood gases (pH >7.30, arterial carbon dioxide tension <50 mmHg, and arterial oxygen tension >60 mmHg) at FIO2 of 0.4, normothermia, and mediastinal drainage (<100 ml/h for 2 h).

VAS was assessed at extubation (V0) and then at 3, 6, 12, 18, and 24 h PO (V1, V2, V3, V4, and V5). Pain severity was divided according to VAS score into four grades: no pain (VAS <4), mild (VAS 4–5), moderate (VAS 6–7), and severe (VAS >7).

Incentive spirometry was done at similar time intervals (S0, S1, S2, S3, S4, and S5) to indicate the IFR (l/min) by assessing the number of balls raised (1 ball=600 ml, 2 balls=900 ml, and 3 balls=1200 ml).

pH, arterial carbon dioxide tension (PaCO2), and PaO2/FIO2 were recorded before induction, at extubation, and at 6, 12, and 24 h PO.

The PO ventilation duration (min) (from arrival to the ICU till extubation), ICU stay (h), and hospital stay (days) were recorded.

Analgesic regimen

All patients were given PO analgesia in the form of intravenous paracetamol 1 g every 6 h. Morphine 2 mg was given intravenously if VAS score was greater than or equal to 3. The total amount of morphine (mg) given during the first PO 24 h and number of request of analgesia (morphine) in first PO 24 h were recorded.

After 24 h, intravenous paracetamol 1 g was given on patient’s request.

Total amount of bupivacaine (mg) consumption over first PO 24 h was recorded.

Statistical analysis

SPSS version 17 program (SPSS Inc., Chicago, Illinois, USA), was used to enter data and statistical analysis. Data were presented as mean±SD, number, median, and interquartile range). Comparison between the two groups was performed using unpaired Student t-tests for parametric data, Mann–Whitney test for nonparametric ordinal data, and χ2-test for data collected as number. P value less than 0.05 was considered as statistically significant.


  Results Top


The two groups were comparable regarding demographic and surgical data ([Table 1]).
Table 1 Demographic and surgical data

Click here to view


VAS in the first PO 24 h was significantly higher in group I than group II at all study times ([Table 2]).
Table 2 Visual analog scale in the first postoperative 24 h.

Click here to view


Severity of pain was significantly higher in group I than group II at all times of examination ([Table 3]).
Table 3 Severity of pain among groups

Click here to view


Total morphine and bupivacaine consumption in the first 24 h and number of request of analgesia (morphine) in first PO 24 h were significantly higher in group I than group II ([Table 4]).
Table 4 Total morphine and bupivacaine consumption (mg) in the first postoperative 24 h and number of request of analgesia (morphine) in first postoperative 24 h

Click here to view


PO IFR (l/min) was significantly higher in group II than group I at all times of study ([Table 5]).
Table 5 Postoperative inspiratory flow rate (l/min)

Click here to view


There were no significant differences between the two groups regarding blood pH and PaCO2, whereas PaO2/FIO2 was significantly higher in group II than group I at all PO study times ([Table 6]).
Table 6 Arterial blood gas parameters

Click here to view


Regarding PO ventilation duration (min), ICU stay (h), and hospital stay (days), they were significantly longer in group I than group II ([Table 7]).
Table 7 Postoperative ventilation duration (min), ICU stay (h), and hospital stay (days)

Click here to view



  Discussion Top


The most often cause of pain after cardiac surgery is the median sternotomy [8]. The most commonly used analgesics in such patients are the parental opioids, which can cause undesirable effects such as respiratory depression, sedation, nausea, and vomiting [3].

This study was designed to examine the efficacy of presternal infusion of bupivacaine 0.25% and US-guided bilateral pectoral nerve block in poststernotomy pain.

Thus study showed that PO VAS was significantly higher in bupivacaine infusion group than Pec group at all observation times, severity of pain was significantly higher in group I than group II at all times of examination, and total morphine (mg) consumption and number of request of analgesia (morphine) in first PO 24 h were significantly higher in bupivacaine infusion group than Pec group. Kumar et al. [7] observed that VAS scores at rest and cough were significantly lower in Pec group than control group at 0, 3, 6, 12, and 18 h from extubation (P<0.05), but at 24 h, VAS scores were comparable between the two groups. Nasr et al. [9] showed that there was lower PO VAS score and marked reduction in morphine requirements (mg) in bupivacaine infusion group compared with control group (8.6±0.94 vs 18.83±3.4 mg, respectively; P=0.02) and attributed such a result to placing catheters for sternal wound infusion closer to the anterior branches of the intercostal nerves that improved the analgesic efficacy. Liu et al. [10] demonstrated that pectoral block provided immediate and sustained pain relief with reduction of opioid requirement. Richard et al. [11] observed that continuous bilateral pectoral nerve 2 block may reduce pain and opioid consumption and extend duration of analgesia after median sternotomy. Chiu et al. [12] found that continuous presternal bupivacaine infusion provided short and long-term pain relief for thoracotomy. Eljezi et al. [13], Dowling et al. [14], and Koukis et al. [15]) showed a reduction in PO pain and opioid requirement after local anesthetic infusion. Magnano et al. [16] and Agarwal et al. [17] showed that local anesthetic presternal infusion after median sternotomy did not reduce PO pain, and VAS score. Magnano et al. [16] attributed their results to using a catheter with few holes only at the tip, which was ineffective for long median sternotomy, and the lower wound segment might be uncovered by anesthetic drug, and advised to prolong the duration of bupivacaine infusion to be more effective for delayed PO pain. Agarwal et al. [17] attributed the failure of their technique to earlier time of discontinuation than planned owing to wound infection.

The present study showed that total bupivacaine (mg) consumption in the first PO 24 h was significantly higher in bupivacaine infusion group (150 mg) than Pec group (43.75 mg), and it was extremely below the toxic dose of bupivacaine (3 mg/kg), especially in Pec group.

This study demonstrated that PO IFR (l/min) was significantly higher in Pec group than bupivacaine infusion group at all time of observation, and this might be owing to lesser PO pain, which facilitated expulsion of secretion and rapid pulmonary rehabilitation with shorter ventilatory duration, ICU, and hospital stay. Kumar et al. [8] observed that peak IFR was higher in Pecs group as compared with control group at 0, 3, 6, 12, 18, and 24 h (P<0.05).

The current study showed that there were no significant differences between the two groups regarding blood pH and PaCO2, whereas PaO2/FIO2 was significantly higher in Pec group than bupivacaine infusion group at all PO study times, which might be owing to better pain control with better respiration. Nasr et al. [9] observed that PaCO2 and pH were accepted in both bupivacaine infusion group and control group, with no significant differences, but PaO2/FIO2 was significantly higher in bupivacaine infusion group compared with control group (P<0.05). Eljezi et al [13] demonstrated no improvement in the PO respiratory functions despite improvement of analgesia in the ropivacaine infusion group and explained such result to that sternotomy pain was a minor factor in the respiratory dysfunction observed.The present study demonstrated that PO ventilation time (min), ICU stay (h), and hospital stay (days) were significantly longer in bupivacaine infusion group than Pec group. Nasr et al. [9] showed that there was shorter extubation time in bupivacaine infusion group (117±10 min) compared with the control group (195±19 min), but no differences in ICU or hospital stay duration. Richard et al. [11] observed that continuous bilateral pectoral nerve block reduced length of hospital stay. Eljezi et al. [13], Dowling et al. [14], and Koukis et al. [15] showed a significant decrease in hospital stay time. Magnano et al. [16] and Agarwal et al. [17] showed that local anesthetic presternal infusion after median sternotomy did not reduce extubation time.


  Conclusion Top


First, US-guided bilateral Pec block is a safe and effective technique for controlling poststernotomy pain than continuous presternal bupivacaine infusion with lower VAS score and pain severity, less bupivacaine (mg) and morphine consumption, and less number of request of analgesia (morphine). Second, PEC block showed better IFR and PaO2/FIO2, with shorter duration of ventilation, ICU stay, and hospital stay.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Blanco R, Parras T, McDonnell JG, Prats-Galino A. Serratus plane block: a novel ultrasound‑guided thoracic wall nerve block. Anesth 2013; 68:1107–1113.  Back to cited text no. 1
    
2.
Liu SS, Block BM, Wu C. Effects of perioperative central neuraxial analgesia on outcome after coronary artery bypass surgery: a meta-analysis. Anesthesiology 2004; 101:153–161.  Back to cited text no. 2
    
3.
Power I. Recent advances in postoperative pain therapy. BJA 2005; 95:43–51.  Back to cited text no. 3
    
4.
McDonald SB, Jacobsohn E, Kopacz DJ, Desphande S, Helman JD, Salinas F et al. Parasternal block and local anesthetic infiltration with levobupivacaine after cardiac surgery with desflurane: the effect on postoperative pain, pulmonary function, and tracheal extubation times. Anesth Analg 2005; 100:25–32.  Back to cited text no. 4
    
5.
Goswami S, Kundra P, Bhattacharyya J. Pectoral nerve block1 versus modified pectoral nerve block 2 for postoperative pain relief in patients undergoing modified radical mastectomy: a randomized clinical trial. BJA 2017; 119:830–835.  Back to cited text no. 5
    
6.
Blanco R, Fajardo M, Parras Maldonado T. Ultrasound description of Pecs II (modified Pecs I): a novel approach to breast surgery. Rev Esp Anestesiol Reanim 2012; 59:470–475.  Back to cited text no. 6
    
7.
Kumar KN, Kalyane RN, Singh NG, Nagaraja PS, Krishna M, Babu B et al. Efficacy of bilateral pectoralis nerve block for ultrafast tracking and postoperative pain management in cardiac surgery. Ann Card Anesth 2018; 21:333–338.  Back to cited text no. 7
    
8.
Jensen MP, Chen C, Brugger AM. Interpretation of visual analog scale ratings and change scores: a reanalysis of two clinical trials of postoperative pain. J Pain 2003; 4:407–414.  Back to cited text no. 8
    
9.
Nasr DA, Abdelhamid HM, Mohsen M, Aly AH. The analgesic efficacy of continuous presternal bupivacaine infusion through a single catheter after cardiac surgery. Ann Cardiac Anesth 2015; 18:15–20.  Back to cited text no. 9
    
10.
Liu V, Mariano ER, Prabhakar C. Pecto-intercostal fascial block for acute poststernotomy pain: a case report. Anesth Analg 2018; 10:12.  Back to cited text no. 10
    
11.
Richard AM, Bain SE, Nikravan S, Ryan R, Lilley RR, Velamoor GR et al. Continuous pectoral fascia blocks for postoperative analgesia after median sternotomy (case report). Anesth Analg 2018; 11:6.  Back to cited text no. 11
    
12.
Chiu KM, Wu CC, Wang MJ, Lu CW, Shieh JS, Lin TY et al. Local infusion of bupivacaine combined with intravenous patient-controlled analgesia provides better pain relief than intravenous patient-controlled analgesia alone in patients undergoing minimally invasive cardiac surgery. J Thorac Cardiovasc Surg 2008; 135:1348–1352.  Back to cited text no. 12
    
13.
Eljezi V, Dualé C, Azarnoush K, Skrzypczak Y, Sautou V, Pereira B et al. The analgesic effects of a bilateral sternal infusion of ropivacaine after cardiac surgery. Reg Anesth Pain Med 2012; 37:166–174.  Back to cited text no. 13
    
14.
Dowling R, Meier KT, Ghaly A, Barber D, Boice T, Dine A. Improved pain control after cardiac surgery: results of a randomized, double-blind, clinical trial. J Thorc Cardiovasc Surg 2003; 126:1271–1278.  Back to cited text no. 14
    
15.
Koukis I, Argiriou M, Dimakopoulou A, Panagiotakopoulos V, Theakos N, Charitos C. Use of continuous subcutaneous anesthetic infusion in cardiac surgical patients after median sternotomy. J Cardiothorac Surg 2008; 3:2.  Back to cited text no. 15
    
16.
Magnano D, Montalbano R, Lamarra M, Ferri F, Lorini L, Clarizia S et al. Ineffectiveness of local wound anesthesia to reduce postoperative pain after median sternotomy. J Card Surg 2005; 20:314–318.  Back to cited text no. 16
    
17.
Agarwal S, Nuttall GA, Johnson ME, Hanson AC, Oliver WC Jr. A prospective, randomized, blinded study of continuous ropivacaine infusion in the median sternotomy incision following cardiac surgery. Reg Anesth Pain Med 2013; 38:145–150.  Back to cited text no. 17
    


    Figures

  [Figure 1]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
Aim
Patients and methods
Results
Discussion
Conclusion
References
Article Figures
Article Tables

 Article Access Statistics
    Viewed132    
    Printed4    
    Emailed0    
    PDF Downloaded35    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]