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 Table of Contents  
Year : 2014  |  Volume : 28  |  Issue : 3  |  Page : 160-165

Thoracic paravertebral block for analgesia after modified radical mastectomy

1 Associate Professor, Department of Anesthesia, Gujarat Cancer and Research Institute, Civil Hospital Campus, Asarwa, Ahmedabad, Gujarat, India
2 Professor, Department of Anesthesia, Gujarat Cancer and Research Institute, Civil Hospital Campus, Asarwa, Ahmedabad, Gujarat, India
3 Resident, Department of Anesthesia, Gujarat Cancer and Research Institute, Civil Hospital Campus, Asarwa, Ahmedabad, Gujarat, India
4 Professor and Head of the Department, Department of Anesthesia, Gujarat Cancer and Research Institute, Civil Hospital Campus, Asarwa, Ahmedabad, Gujarat, India

Date of Web Publication11-Aug-2014

Correspondence Address:
Leena P Patel
15, Devchhaya Society, Opp. Satadhar Society, Near Satadhar Cross Road, Sola Road, Ahmedabad - 380 061, Gujarat
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0970-5333.138452

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Background: Surgical intervention is associated with postoperative pain, nausea and vomiting. Paravertebral blockade (PVB) has been advocated as a useful technique for analgesia after breast surgery. Aims and Objectives: The aim is to study the efficacy of PVB and associated complications against intramuscular diclofenac sodium 0.75mg. Materials and Methods: Fifty patients of ASA grade I and II were randomized to receive either PVB (group A) or intramuscular diclofenac sodium (group B); there were 25 patients in each group. Group A patients received PVB with catheter at T3 and T6 levels with 0.3ml/kg 0.25% bupivacaine, whereas group B patients received intramuscular diclofenac sodium preoperatively. All patients were observed for quality and duration of analgesia, incidence of nausea and vomiting, hemodynamic stability, and complication. Results: The patients given PVB experienced lower visual analog score (VAS) at rest (P < 0.001) and longer duration of analgesia (P < 0.001) on movement (P < 0.0001) for 1 to 12 h in postoperative period as compared to group B. In group A, fewer patients required rescue analgesia and experienced less postoperative nausea and vomiting as compared to group B. Conclusion: PVB provides better pain control and decreased nausea and vomiting after modified radical mastectomy.

Keywords: Catheter technique, mastectomy, paravertebral block, postoperative pain

How to cite this article:
Patel LP, Sanghvi PR, Agarwal MB, Prajapati GC, Patel BM. Thoracic paravertebral block for analgesia after modified radical mastectomy . Indian J Pain 2014;28:160-5

How to cite this URL:
Patel LP, Sanghvi PR, Agarwal MB, Prajapati GC, Patel BM. Thoracic paravertebral block for analgesia after modified radical mastectomy . Indian J Pain [serial online] 2014 [cited 2023 Mar 23];28:160-5. Available from: https://www.indianjpain.org/text.asp?2014/28/3/160/138452

  Introduction Top

Breast cancer is the most common cancer among women and most of them require breast surgery. [1] Surgery is associated with nausea vomiting, postoperative pain and chronic pain. Acute postoperative pain is an important risk factor for the development of persistent chronic postoperative pain after breast surgery. [2] Therefore, effective postoperative pain management after breast cancer surgery is necessary. A paravertebral block (PVB) for breast surgery has increasing popularity and considered a technique of choice for anesthesia and postoperative analgesia during breast surgery. [3],[4],[5],[6] There are two common variations; first is a single site injection that involves larger volume at one paravertebral space, [7] and the second is a multiple site injection in which 3-4 cm 3 volume is injected into multiple levels. The single site technique is reported to provide unilateral anesthesia from only 4-5 dermatomes, which may not be sufficient to cover all relevant dermatomes. [8] A recent study shows that 97% of patients had adequate analgesia with four injections compared to only 11% for single injection. [9]


We decided to study multiple site injection to get intense analgesia. To avoid pain and discomfort of multiple pricks, we introduced a catheter via paravertebral space before the induction of general anesthesia (GA). By this technique, we can avoid injection of larger volume at a single site and relevant complications. This study was planned to study the efficacy of PVB via this technique.


The paravertebral space is a wedge-shaped area with parietal pleura as anterolateral boundary; base is formed by the posterolateral aspect of vertebral body, the intervertebral disk and the foramen is the base, the superior costotransverse ligament (SCTL), which is located between the lower border of the transverse process above and upper border of transverse process below, the internal intercostal membrane as the posterior boundary and it is continuous with the intercostal space laterally.

  Materials and Methods Top

After approval from institutional review board, 50 patients of ASA grade I and II undergoing modified radical mastectomy with axillary dissection were selected. Patients with any contraindication for regional anesthesia such as infection at the puncture site, anatomical deformity or coagulation disorders were excluded.

All patients were randomly divided into two groups. Group A patients received PVB while group B patients received injection diclofenac sodium 75 mg intramuscularly before incision closure.

All the patients were pre-medicated with injection midazolam hydrochloride 2 mg intravenous. PVB was performed in preoperative holding area after application of monitor for ECG, BP and SPO 2 .

The block was performed according to the technique described by Eason and Wyatt. [10] The patient was placed in the lateral position with side to be blocked uppermost. T6 spinous process was identified by decrement from C7. Skin was punctured approximately 3 cm lateral from midline and level with the cephalad end of the spinous process under local anesthesia. Under aseptic condition, needle was advanced at 90 degrees to the skin in all plains to strike the transverse process at the depth of 3 to 3.5 cm. The needle was then walked off the surface of the transverses process and advanced 1 to 2 cm further. Loss of resistance to saline indicated the passage of the needle through the costotransverse ligament into the paravertebral space. A catheter was introduced and advanced 4 to 5 cm into the space to reach at T3 level. We calculated the total dose as 0.3 ml/kg of 0.25% bupivacaine. After negative aspiration, we gave one-third of the calculated dose at this level, the catheter was withdrawn 1.5 cm and another one-third dose was given. Again, the catheter was withdrawn another 1.5 cm and the remaining drug was given at this level and the catheter was removed. We targeted block T1 to T10 dermatomes. Patients' vitals were observed for 20 min at every 5 min intervals.

GA was induced in all patients with injection propofol (2 mg/kg), fentanyl citrate (2 μg/kg) and vecuronium bromide. Anesthesia was maintained with isoflurane, nitrous oxide and oxygen keeping FIO 2 0.5%. Group B patients were given intramuscular diclofenac sodium 75 mg before the closure of incision. All patients were extubated and transferred to the postoperative ward. Patients were shown a VAS, one end of which was marked as no pain and the other end was marked intolerable pain as 10. Patients were asked to mark on this line the point that best reflected their pain at rest and on movement. Postoperative pain was assessed by VAS at 10 min, 30 min and 1 h intervals during the first 12 h and thereafter by verbal contact. Patients of both the groups received injection tramadol hydrochloride 50 mg IV when VAS>3 as rescue analgesia. Nausea and vomiting was treated with injection ondansetron hydrochloride 8 mg IV as and when required. The patients were evaluated for 24 h and requested to document VAS, episode of nausea and vomiting, requirement of rescue analgesia, duration of analgesia, and for any complications.

Statistical analysis

We considered patients according to their allocated groups and analyzed results using SPSS version 10 for Windows (SPSS Inc., Chicago, IL). Intraoperative and postoperative values were averaged for each patient and the resulting values were averaged among the patients in each group. Excel program computed the mean values over each hour for pulse, BP, VAS and other measures. These data were inspected for distribution and then compared between the groups using Mann-Whitney U tests as appropriate. P < 0.05 was considered statistically significant. Parametric data were reported as mean ± SD.

Observation and results

Fifty patients aged between 29 and 67 years were selected and divided into two groups. Patients' characteristics and vital data were similar at baseline in both the groups [Table 1]. All the patients were operated for mastectomy with axillary dissection. Patients were hemodynamically stable after block as shown in [Figure 1]. In postoperative ward, pulse, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were slightly lower in group A but was not statistically significant [Table 2]. VAS at rest was significantly lower in group A at 6 h (P < 0.001) and at 12 h (P < 0.0009) as shown in [Figure 2]. There was no restriction of shoulder movement as indicated by similar flexion and abduction on the preoperative day, in the recovery room and on the first postoperative day in group A. VAS on movement was significantly lower in group A at 6 h (P < 0.0001) and at 12 h (P < 0.010) as shown in [Figure 3]. Duration of analgesia in group A was 14 ± 1.5 hours, whereas it was 6 ± 0.3 in group B [Table 3], which was significantly (P < 0.0001) higher in group A. One patient in group A experienced analgesia for more than 24 h. Three patients in group A needed rescue analgesia, whereas nine patients in group B needed rescue analgesia. One patient in group A suffered from nausea and vomiting, whereas 10 patients suffered nausea and vomiting [Table 4] in group B. We did not encounter any complications like vascular puncture, hypotension, bradycardia, pleural puncture, and pneumothorax or Horner's syndrome.
Table 1: Demographic data

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Table 2: Postoperative changes in vital data at various time intervals

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Table 3: Duration of analgesia

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Table 4: Rescue analgesia and PONV

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Figure 1: Vital data immediately after block data are presented as mean pulse, SBP, DBP ± SD before giving PVB and at 10 min, 20 min, 30 min after giving PVB

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Figure 2: VAS score at rest in recovery room Mean VAS SD reported by patients at 0 min, 30 min, 1 h, 2 h and thereafter 2 h intervals up to 12 h.

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Figure 3: VAS score on movement in recovery room Mean VAS ± SD reported on movement by patients at 0 min, 30 min, 1 h, 2 h and thereafter 2 h intervals up to 12 h.

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  Discussion Top

Regional anesthesia can decrease episodes of nausea vomiting and postoperative pain by pre-emptive analgesic effect. [11] Various methods of regional anesthesia for breast surgery are in practice. Simple infiltration methods provide adequate anesthesia for minor procedures but patient discomfort, frequent supplementation and distortion of anatomy may preclude their use for major procedures. Thoracic epidurals are associated with cardiorespiratory and physiological changes, which required an increased level of monitoring when used for postoperative analgesia. Paravertebral analgesia consistently achieve superior analgesia and inhibit the surgical stress response at greater extent than epidural anesthesia. [6],[12]

Our study showed that a PVB with bupivacaine 0.25% performed before GA in patients scheduled for breast surgery resulted in lower need for postoperative opioid analgesic and in lower overall intensity of pain on the first postoperative day. Maximum mean VAS reported by our patients in group A was 1.57 ± 0.5 up to 12 h, whereas in group B it was 3.4 ± 1.85. Data from six trials of 344 patients assessing acute postoperative pain after breast surgery in PVB alone and with GA showed that there was a significant difference in worst pain scores at rest and during movement between the two groups at <2 h, 2-24 h and 24-48 h. [3],[4],[13],[14] The number of patients requiring opioids was significantly lower in women undergoing surgery with PVB. [15] In an observer blinded study Pusch et al., 86 randomized patients received either a single injection of bupivacaine 0.3 ml/kg at T4 or GA. [3] Pain during movement was lower in PVB group at 1, 6 and 24 h after surgery. Similar results were obtained in a randomized study by Klein et al.[4] and in another study using multilevel injection PVB at T1 to T7 by Naza et al.[13] using a nerve stimulation-guided technique or GA. They found pain scores both at rest and during movement, consumption of analgesic, and incidence of postoperative nausea and vomiting (PONV) significantly lower in PVB group during the first three postoperative days as compared to GA alone in patients undergoing breast surgery.

Schnabel et al. found lower number of patients requiring postoperative opioids and lower risk of PONV at 0-24 h in PVB combined with GA group as compared with GA alone. [1] In our study, 12% of patients required rescue analgesia in group A as compared to 36% of patients in group B. Kairaluoma et al. studied 30 patients with PVB for breast surgery and found that the patients given PVB with bupivacaine had less postoperative pain, longer time to first analgesic dose, lower VAS and 40% smaller oxycodone consumption in post-anesthesia care unit (PACU). [3],[4],[5],[8] The fact that the initial postoperative analgesia was relatively good may have added certain beneficial consequences. The smaller amount of opioid consumed by PVB patients in comparison with controlled patients in the PACU might be responsible for the rapid recovery and the infrequent PONV in the patients given PVB with bupivacaine before surgery. [5] Only 4% patients experienced nausea and vomiting in group A, whereas 40% patients experienced PONV in group B.

Terheggen et al. found a significant postoperative pain reduction in the PVB group and pain in the GA group. [14] It was relatively mild and of short duration. They found less PONV in both groups, which contrasts with observations of Klein et al.[4] and Pusch et al.[3] This may be because of the differences in patient selection, procedure underwent and the technique of GA in both studies.

It was thought inhuman to inject placebo in paravertebral space of our patients in the control group. The results of our study suggest that PVB can provide better analgesia in the first 24 h after breast surgery. The duration of analgesia may last for more than 24 h after block. PVB has been shown to be uniquely effective in eliminating cortical responses to thoracic dermatomal stimulation, which inhibit central reflex involved in pain. Greengrass and colleagues showed that PVB for breast cancer surgery can be successfully performed in a majority of patients with few side effects. They reported incidence of nausea and vomiting at 30%; none of the patients required parenteral opioids and return to ambulatory care unit early by passing recovery room. [11] Similar results were found in a study of 156 cases by Coveney et al. for operative procedure for breast and axilla in 85% of all cases with PVB alone and in 91% of cases with supplementation of local anesthetic. They found this technique to be associated with decreased incidence of nausea and vomiting requiring medication only in 20% of patients, minimal complication and a low rate of conversion to GA. It also improves quality of recovery and provides ambulatory discharge. [12]

In a study of postoperative flap, tissue oxygen tension after immediate latissimus dorsi breast reconstruction surgery, Buggy and colleagues revealed that the mean PaO 2 over the 20 h period was significantly higher in patients receiving paravertebral anesthesia. Intraoperative blood loss and dynamic and static VAS for postoperative pain score was significantly lower in paravertebral patients. [16] In a prospective multiple patient study, the technique seemed safe and reliable in many patients. [17]

The disadvantage of the technique may be the requirement of positioning and multiple injection and inadvertent injection into epidural space. Surgically acceptable conditions for breast surgery, including axillary dissection have been accomplished by single injection of PVB. [3],[13] Whether a multi-injection technique at C7-T6 or C7-T7 [4],[11],[12],[18] is superior to a single injection [3],[5],[13] technique for breast surgery has not been evaluated. Patients belonging in the PVB with single injection group had lower VAS and less restriction in the movement of the shoulder in the early postoperative period. [19] An analysis investigating single and multiple injection technique showed better results for the multiple injection PVB trials in all time periods. [15] They found significant reduction in pain score at rest and during movement. There is a possibility of inadequate block even with multiple injection in 15% of the patients. [3],[12] Recommended volumes of local anesthetic for PVB vary and have found single site injection of 15-20 ml [10] as effective as multiple site injection of 3 to 4 ml per level. [4],[11],[12] A single injection might be diminishing the need for sedation during performance of PVB. It might be logical to assume that a multiple injection technique multiplies the probability of direct puncture-related complication with the number of puncture. A catheter introduction makes it possible to fractionate the amount of injected local anesthetic solution. The disadvantage of introducing a catheter is an inadvertent epidural placement of it. Terheggen and colleagues found inadvertent epidural placement of catheter in one patient and confirmed it by radiograph contrast evaluation. [14] Although ultrasound-guided regional anesthesia has become increasingly popular and may increase safety, current evidence does not suggest that the use of ultrasound improves success of regional anesthesia versus most other techniques. [1] Greengrass and colleagues describe a technique whereby a transverse process is initially contacted by the needle with subsequent caudal advancement of the needle. [11] The practical performance of PVB is still based on indirect methods of identification of paravertebral space, such as loss of resistance, [10] bone contact [11] and pressure measurement. [20]

We did not encounter any complications during the study. This might be because of the small number of patients taken for study. Greengrass et al. experienced no complication of pneumothorax, epidural or spinal spread, or local anesthetic toxicity. [11] Similarly, Klein et al. found no complication in his series of patients. [4] Vila et al. had performed approximately 1,000 PVBs at H. Lee Moffitt Cancer Center, USA, over the last three years and have not encountered a single pneumothorax. [7] They had two patients with seizures, which occurred at the concurrent administration of 80 mg lidocaine hydrochloride to blunt the pain of propofol injection. Lonnqvist et al.[17] had studied 319 adults and 48 children for failure rates and complications following PVB and found the failure rate in adults to be 10.7% whereas in children at 6.2%. Three adults experienced pleural puncture with one developing a pneumothorax. Evidence of epidural spread occurred in 1.1%; one patient experienced seizure. No lumber puncture was reported. In another study by Naja and Lonnqvist, [21] frequency of complications recorded were: failure rate (6.1%), inadvertent vascular puncture (6.8%), hypotension (4%), hematoma (2.4%), pain at the site of puncture (1.3%), sign of epidural or intrathecal spread (1%), plural puncture (0.8%) and pneumothorax (0.5%). [21]

Three patients with functioning PVB reported brachial neuritis pain involving cervical dermatomes C4 to C6. [16] Kairaluoma et al.[5] reported one patient with moderate bilateral convulsions without losing consciousness, which was stopped after administration of diazepam 5 mg IV.

Another recent study by Kairaluoma et al. suggest additional benefits to this procedure, including decreased development of chronic pain and decreased cancer recurrence. [22] In their study, none of the patients in the PVB group developed chronic post-surgical pain compared with 80% of the patients in the standard management group. A study by Exadaktylos et al. found metastasis-free survival was 94% in paravertebral group compared with 77% in GA group at 36 months. [23]

  Conclusion Top

PVB is a safe, effective and easier technique for post-mastectomy pain relief. It is associated with fewer complications and less PONV. By catheter technique, we could get advantages of single injection and at the same time can avoid complications of injecting larger volumes of local anesthetic agent at single space. Recent studies suggest additional benefits to this procedure, including decreased development of chronic pain and decreased cancer recurrence by eliminating stress response at greater extent. Author will keep following up for these extended benefits for future prospects.

  References Top

1.Schnabel A, Reichl SU, Kranke P, Pogatzki-Zahn EM, Zahn PK. Efficacy and safety of paravertebral block in breast surgery: A meta-analysis of randomized control trials. Br J Anaesth 2010;105:842-52.  Back to cited text no. 1
2.Poleshuck EL, Katz J, Andrus CH, Hogan LA, Jung BF, Kulick DI, et al. Risk factors for chronic pain following breast cancer surgery: A prospective study. J Pain 2006;7:626-34.  Back to cited text no. 2
3.Pusch F, Freitag H, Weinstabl C, Obwegeser R, Huber E, Wildling E. Single injection paravertebral block compare to general anesthesia in breast surgery. Acta Anesthesiol Scand 1999;43:770-4.  Back to cited text no. 3
4.Klein SM, Bergh A, Steele SM, Georgiade GS, Greengrass RA. Thoracic paravertebral block for breast surgery. Anesth Analg 2000;90:1402-5.  Back to cited text no. 4
5.Kairaluoma PM, Bachman MS, Korpinen AK. Single injection paravertebral block before general anesthesia enhances analgesia after breast cancer surgery with and without associated lymph node biopsy. Anesth Analg 2004;99:1837-43.  Back to cited text no. 5
6.Richardson J, Sabanathan S, Jones J, Shah RD, Cheema S, Mearns AJ. A prospective, randomized comparison of preoperative continuous balanced epidural or paravertebral bupivacaine on post thoracotomy pain, pulmonary function and stress response. Br J Anesth 1999;83:387-92.  Back to cited text no. 6
7.Vila H Jr, Liu J, Kavasmaneck D. Paravertebral block: New benefits from an old procedure. Curr Opin Anesthesiol 2007;20:316-8.  Back to cited text no. 7
8.Karmakar MK. Thoracic paravertebral block. Anesthesiology 2001;95:771-80.  Back to cited text no. 8
9.Naja ZM, El-Rajab M, Al-Tannir MA, Ziade FM, Tayara K, Younes F, et al. Thoracic paravertebral block: Influence of the number of injections. Reg Anesth Pain Med 2006;31:196-201.  Back to cited text no. 9
10.Eason MJ, Wyatt R. Paravertebral thoracic block - a reappraisal. Anesthesia 1979;34:638-42.  Back to cited text no. 10
11.Greengrass R, O'Brien F, Lyerly K, Hardman D, Gleason D, D'Ercole F, et al. Paravertebral block for breast cancer surgery. Can J Anesth 1996;43:858-61.  Back to cited text no. 11
12.Coveney E, Weltz CR, Greengrass R, Iglehart JD, Leight GS, Steele SM, et al. Use of paravertebral block anesthesia in the surgical management of breast cancer: Experience in 156 cases. Ann Surg 1998;227:496-501.  Back to cited text no. 12
13.Naza MZ, Ziade MF, Lonnqvist PA. Nerve stimulator guided paravertebral blockade vs. general anesthesia for breast surgery: A prospective randomized trial. Eur J Anesthesiol 2003;20:897-903.  Back to cited text no. 13
14.Terheggen MA, Wille F, Borel Rinkes IH, Ionescu TI, Knape JT. Paravertebral blockade for minor breast surgery. Anesth Analg 2002;94:355-9.  Back to cited text no. 14
15.Kotze A, Scally A, Howell S. Efficacy and safety of different techniques of paravertebral block for analgesia after thoracotomy: A systematic review and meta regression. Br J Anaesth 2009;103:626-36.  Back to cited text no. 15
16.Buggy DJ, Kerin MJ. Paravertebral analgesia with Levobupivacaine increases Postoperative flap tissue oxygen tension after immediate latissimus dorsi breast reconstruction compared with intravenous opioid analgesia. Anaesthesiology 2004;100:375-80.  Back to cited text no. 16
17.Lönnqvist PA, MacKenzie J, Soni AK, Conacher ID. Paravertebral blockade. Failure rate and complication. Anesthesia 1995;50:813-5.  Back to cited text no. 17
18.Weltz CR, Greengrass RA, Lyerly HK. Ambulatory surgical management of breast carcinoma using paravertebral block. Ann Surg 1995;222:19-26.  Back to cited text no. 18
19.Sidiropoulou T, Buonomo O, Fabbi E, Silvi MB, Kostopanagiotou G, Sabato AF, et al. A prospective comparison of continuous wound infiltration with ropivacaine versus single injection paravertebral block after modified radical mastectomy. Anesth Analg 2008;106:997-1001.  Back to cited text no. 19
20.Marhofer P, Kettner SC, Hajbok L, Dubsky P, Fleischmann E. Lateral ultrasound guided paravertebral blockade: An anatomical based description of a new technique. Br J Anaesth 2010;105:526-32.  Back to cited text no. 20
21.Naja Z, Lonnqvist PA. Somatic paravertebral nerve blockade. Anesthesia 2001;56:1181-201.  Back to cited text no. 21
22.Kairaluoma PM, Bachmann MS, Rosenberg PH, Pere PJ. Preincisional paravertebral block reduces the prevalence of chronic pain after breast surgery. Anesth Analg 2006;103:703-8.  Back to cited text no. 22
23.Exadaktylos AK, Buggy DJ, Moriarty DC, Mascha E, Sessler DI. Can anesthetic technique for primary breast cancer surgery affect recurrence or metastasis? Anesthesiology 2006;105:660-4.  Back to cited text no. 23


  [Figure 1], [Figure 2], [Figure 3]

  [Table 1], [Table 2], [Table 3], [Table 4]

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