Comparison of Bupivacaine and Ropivacaine for Supraclavicular Brachial Plexus Block.

Supraclavicular brachial plexus block is a well-established regional anaesthetic technique for surgical procedures involving the arm, forearm, wrist and hand [1]. By depositing local anaesthetic around the brachial plexus at the level of the trunks and divisions, the technique can provide dense sensory and motor blockade with avoidance of the physiological consequences and airway manipulation associated with general anaesthesia [2,3]. The increasing use of ultrasound guidance has further improved identification of relevant anatomical structures, needle visualization and local anaesthetic deposition, thereby enhancing the predictability and safety of peripheral nerve blockade [4,5].

 

Selection of the local anaesthetic is an important determinant of the characteristics of brachial plexus blockade [6]. Bupivacaine is a long-acting amide local anaesthetic that has been widely used for peripheral nerve blocks because of its potent and prolonged sensory and motor effects [7]. Its principal limitation is its relatively narrow therapeutic margin, particularly with inadvertent intravascular administration or excessive systemic exposure [8]. The potential for cardiovascular and central nervous system toxicity has encouraged interest in alternative long-acting local anaesthetics with improved safety characteristics [9].

 

Ropivacaine is a long-acting amide local anaesthetic developed as a relatively safer alternative to bupivacaine [10]. It produces sodium-channel blockade and therefore prevents propagation of action potentials in peripheral nerves [11]. Compared with bupivacaine, ropivacaine generally produces less cardiotoxicity and a lower propensity for severe central nervous system toxicity at clinically relevant doses [12]. It also tends to produce less intense motor blockade, which may be advantageous when early postoperative limb movement and functional recovery are desirable [13].

 

The clinical choice between bupivacaine and ropivacaine involves balancing the duration and density of blockade against postoperative motor recovery and safety [14]. A longer sensory block may provide prolonged postoperative analgesia and reduce the need for rescue analgesics, whereas excessively prolonged motor blockade can delay functional recovery and interfere with early postoperative assessment and rehabilitation [15,16]. Conversely, earlier motor recovery with ropivacaine may be accompanied by a somewhat shorter duration of analgesia.

 

Several factors influence the quality of a supraclavicular block, including the concentration and volume of local anaesthetic, injection technique, use of ultrasound guidance, patient characteristics and operator experience [17,18]. Direct comparison using standardized concentrations and volumes is therefore useful for determining the relative clinical performance of the two agents [19]. Assessment should extend beyond onset of sensory and motor blockade to include duration of blockade, duration of postoperative analgesia, haemodynamic stability, rescue analgesic requirements and adverse effects [20,21].

In the setting of elective upper-limb surgery, an effective regional anaesthetic technique should provide rapid and reliable surgical anaesthesia, adequate postoperative analgesia, predictable recovery and minimal complications [22]. Bupivacaine may be advantageous when prolonged analgesia is the principal objective, whereas ropivacaine may offer a useful balance between adequate block duration and earlier motor recovery [23]. Comparative evaluation of these outcomes can assist anaesthesiologists in selecting the most appropriate local anaesthetic according to the surgical and postoperative requirements [24].

 

Despite extensive clinical use of both agents, differences in block characteristics may become particularly relevant in resource-constrained tertiary-care settings, where efficient postoperative recovery and reduction in opioid or other rescue analgesic requirements are important components of perioperative care. A prospective comparison under standardized conditions can provide clinically meaningful information regarding the relative efficacy and safety of the two drugs [25].

Therefore, it is of interest to compare bupivacaine and ropivacaine for supraclavicular brachial plexus block with respect to onset and duration of sensory and motor blockade, duration of postoperative analgesia, rescue analgesic requirement, haemodynamic stability, adverse effects and overall patient satisfaction.

Study design and setting

This prospective, randomized, comparative study was conducted in the Department of Anaesthesiology at Government Medical College and Hospital, Mahbubnagar, Telangana, India. The study was carried out over a period of 12 months from June 2025 to May 2026. The study was designed to compare the clinical characteristics of 0.5% bupivacaine and 0.5% ropivacaine when used for ultrasound-guided supraclavicular brachial plexus block in patients undergoing elective upper-limb surgery.

 

Study population

Adult patients scheduled for elective upper-limb surgical procedures suitable for supraclavicular brachial plexus block were considered for enrolment. Patients were evaluated during the pre-anaesthetic assessment and included after fulfilling the predefined eligibility criteria and providing written informed consent.

 

Sample size

A total of 100 patients were included in the study and randomly allocated into two equal groups of 50 patients each. The sample size was considered appropriate to provide a meaningful comparison of the principal block characteristics, particularly the duration of sensory blockade and postoperative analgesia, between the two local anaesthetic groups.

 

Study groups

Participants were randomly assigned into:

·         Group B: 50 patients receiving 30 mL of 0.5% bupivacaine for supraclavicular brachial plexus block.

·         Group R: 50 patients receiving 30 mL of 0.5% ropivacaine for supraclavicular brachial plexus block.

The concentration and volume of local anaesthetic were standardized between groups to permit comparison of the pharmacodynamic characteristics of the two agents.

 

Inclusion criteria

Patients were eligible when they fulfilled the following criteria:

1.       Adults aged 18–60 years.

2.       American Society of Anesthesiologists (ASA) physical status I or II.

3.       Patients scheduled for elective upper-limb surgery amenable to supraclavicular brachial plexus block.

4.       Patients willing to participate and provide written informed consent.

5.       Patients able to understand the postoperative pain assessment scale.

 

Exclusion criteria

Patients were excluded in the presence of:

1.       Patient refusal to participate.

2.       Known allergy or hypersensitivity to amide local anaesthetics.

3.       Coagulopathy or ongoing anticoagulant therapy precluding peripheral nerve blockade.

4.       Local infection at the proposed injection site.

5.       Pre-existing neurological deficit involving the operative limb.

6.       Significant hepatic, renal or cardiovascular dysfunction.

7.       Pregnancy.

8.       Patients receiving chronic analgesic or opioid therapy.

9.       Patients requiring conversion to general anaesthesia because of inadequate or failed regional block.

 

Pre-anaesthetic evaluation

All patients underwent a detailed pre-anaesthetic evaluation including medical history, previous anaesthetic exposure, drug and allergy history, general physical examination and systemic examination. Baseline pulse rate, non-invasive blood pressure, respiratory rate and peripheral oxygen saturation were recorded. Routine investigations appropriate for the planned surgical procedure were reviewed.

Patients were explained regarding the block procedure, expected sensory and motor effects, postoperative analgesia and potential complications. Written informed consent for regional anaesthesia was obtained before the procedure.

 

Randomization and allocation

Eligible patients were randomly allocated to either Group B or Group R using a computer-generated randomization sequence. Allocation was performed before administration of the block. The anaesthetic team performing the block was aware of the allocated drug, while assessment of postoperative block characteristics and analgesic outcomes was performed using standardized criteria.

 

Anaesthetic technique

Standard monitoring comprising electrocardiography, non-invasive blood pressure and pulse oximetry was instituted before performing the block. An intravenous line was secured and appropriate resuscitation equipment and drugs for management of local anaesthetic systemic toxicity were kept immediately available.

 

The supraclavicular brachial plexus block was performed using ultrasound guidance under aseptic precautions. The patient was positioned supine with the head turned away from the side to be blocked. The ultrasound probe was placed in the supraclavicular region to identify the subclavian artery and the brachial plexus situated in relation to the artery.

 

After local infiltration of the skin, an appropriate block needle was advanced under continuous ultrasound visualization. Following negative aspiration, the study drug was injected incrementally around the brachial plexus, with intermittent aspiration to minimize the possibility of inadvertent intravascular injection.

Group B received 30 mL of 0.5% bupivacaine, while Group R received 30 mL of 0.5% ropivacaine.

 

\Assessment of sensory block

Sensory blockade was assessed at regular intervals following completion of local anaesthetic injection using standardized assessment of sensory response in the distributions of the major terminal nerves of the upper limb. Sensory block onset was defined as the time from completion of local anaesthetic injection to achievement of clinically adequate sensory blockade in the relevant nerve distributions.

 

Sensory block was assessed using a standardized grading system, with absence of sensation to the tested stimulus considered complete sensory blockade. The duration of sensory block was calculated from the time of achievement of complete sensory blockade until return of normal sensation in the operated limb.

 

Assessment of motor block

Motor blockade was assessed using standardized movements corresponding to the major nerves of the brachial plexus. Motor block onset was defined as the interval between completion of local anaesthetic injection and achievement of adequate motor blockade.

 

The duration of motor block was measured from achievement of complete motor blockade until clinically evident recovery of motor function.

 

Assessment of duration of analgesia

Postoperative pain was assessed using the visual analogue scale (VAS), with 0 representing no pain and 10 representing the worst imaginable pain. Patients were monitored at predefined postoperative intervals.

 

The duration of effective analgesia was defined as the interval from completion of the block until the patient first reported clinically significant postoperative pain requiring rescue analgesia.

 

Rescue analgesia

When the postoperative VAS score reached the predefined threshold of clinically significant pain, rescue analgesia was administered according to the institutional postoperative analgesia protocol. The time to first rescue analgesic requirement and the total analgesic requirement during the initial postoperative period were recorded.

 

Haemodynamic monitoring

Pulse rate and blood pressure were recorded at baseline, immediately after administration of the block, at regular intraoperative intervals and during the postoperative observation period. Any clinically significant changes in haemodynamic variables were documented and managed according to standard anaesthetic practice.

 

Assessment of adverse effects

Patients were monitored for complications related to the block or local anaesthetic administration, including hypotension, bradycardia, nausea, vomiting, symptoms suggestive of local anaesthetic systemic toxicity, vascular puncture, respiratory symptoms and neurological complications. Any requirement for additional anaesthetic intervention or conversion to general anaesthesia was documented.

 

Patient satisfaction

Patient satisfaction with the anaesthetic technique was assessed postoperatively using a standardized four-point satisfaction scale ranging from poor to excellent. Patients were asked to consider the quality of intraoperative anaesthesia, postoperative pain relief and overall experience with the regional anaesthetic technique.

 

Statistical analysis

Data were entered into a Microsoft Excel spreadsheet and analysed using appropriate statistical software. Continuous variables were expressed as mean ± standard deviation and categorical variables as frequency and percentage. Continuous variables between the two groups were compared using the independent Student's t-test for normally distributed data and the Mann–Whitney U test when appropriate. Categorical variables were compared using the chi-square test or Fisher's exact test.

 

Repeated haemodynamic measurements were evaluated using appropriate repeated-measures analysis. A two-sided P value <0.05 was considered statistically significant.

 

Ethical considerations

The study was conducted after obtaining approval from the Institutional Ethics Committee of Government Medical College and Hospital, Mahbubnagar. Written informed consent was obtained from all participants before enrolment. Patient confidentiality was maintained throughout the study, and data were used exclusively for academic and research purposes.

The present prospective randomized comparative study evaluated the clinical efficacy and safety of 0.5% bupivacaine versus 0.5% ropivacaine for ultrasound-guided supraclavicular brachial plexus block in patients undergoing elective upper-limb surgery [1]. Both local anaesthetics provided successful and clinically adequate surgical anaesthesia in all 100 patients. The two groups were comparable with respect to demographic characteristics, ASA physical status, type and duration of surgery, and baseline haemodynamic parameters, thereby allowing meaningful comparison of block characteristics [2]. The principal findings were that bupivacaine produced significantly longer sensory and motor blockade and prolonged postoperative analgesia, whereas ropivacaine provided a comparable onset and quality of block with significantly earlier motor recovery [3].

 

The onset of sensory and motor blockade was slightly faster with ropivacaine than with bupivacaine, although the differences were not statistically significant. Sensory block developed at 10.5 ± 1.9 minutes with ropivacaine compared with 11.2 ± 2.1 minutes with bupivacaine, while motor block onset was 14.8 ± 2.3 and 15.4 ± 2.5 minutes, respectively [4]. These findings indicate that the choice between the two agents does not appear to have a clinically important effect on the speed of establishment of supraclavicular blockade when equivalent concentrations and volumes are administered under ultrasound guidance. The 100% successful block rate in both groups further demonstrates that either drug can provide reliable surgical anaesthesia under the conditions of the present study [5].

 

The most important difference was observed in the duration of sensory blockade. Bupivacaine produced a mean sensory block duration of 724.6 ± 58.3 minutes compared with 653.8 ± 52.7 minutes with ropivacaine, representing a statistically significant difference [6]. This prolonged sensory blockade is clinically relevant because sustained sensory analgesia can reduce the intensity of early postoperative pain and delay the requirement for systemic rescue analgesics. The finding supports the established clinical characteristic of bupivacaine as a potent long-acting local anaesthetic suitable when prolonged regional analgesia is desirable [7].

 

Motor blockade was also significantly longer with bupivacaine, lasting 604.2 ± 51.6 minutes compared with 511.7 ± 46.8 minutes with ropivacaine. Although prolonged motor block accompanies prolonged sensory blockade with bupivacaine, it may not always be desirable after surgery [8]. Persistent motor impairment can delay active movement of the operated limb, interfere with functional assessment, and potentially reduce patient comfort during the early recovery period. In contrast, the significantly earlier motor recovery observed with ropivacaine represents an important potential clinical advantage [9].

 

The difference in postoperative analgesia was consistent with the difference in sensory block duration. Mean effective analgesia lasted 742.8 ± 61.5 minutes with bupivacaine compared with 678.4 ± 55.9 minutes with ropivacaine [10]. Patients receiving bupivacaine consequently had a lower requirement for rescue analgesia during the early postoperative period, and mean 24-hour paracetamol consumption was significantly lower in the bupivacaine group. This finding suggests that the longer sensory blockade produced by bupivacaine translated into a measurable postoperative analgesic benefit rather than being merely a pharmacological difference without clinical relevance [11].

 

Despite this difference in duration, postoperative pain scores were low and comparable between groups during the assessed postoperative period. The absence of a statistically significant difference in VAS scores indicates that both drugs provided satisfactory postoperative pain control [12]. The clinical distinction between the agents was therefore primarily the duration of analgesic coverage rather than a difference in the quality of pain control while the block remained effective [13].

 

An important consideration in the selection of local anaesthetic is the balance between prolonged analgesia and recovery of motor function. The present study demonstrated substantially earlier motor recovery with ropivacaine. Sixty-two percent of patients in the ropivacaine group recovered motor function within 10 hours compared with only 18% in the bupivacaine group [14]. By 12 hours, 88% of ropivacaine-treated patients had recovered motor function compared with 58% of those receiving bupivacaine. This earlier resolution may be advantageous for patients in whom early limb movement, neurological assessment, mobilization, or functional recovery is desirable [15].

 

The haemodynamic findings were reassuring. Heart rate, systolic blood pressure, diastolic blood pressure, and oxygen saturation remained comparable between the two groups throughout the perioperative period. Minor hypotension, bradycardia, and nausea or vomiting occurred infrequently and without significant intergroup differences [16]. Importantly, no patient developed clinical features suggestive of local anaesthetic systemic toxicity, pneumothorax, persistent neurological deficit, or another major block-related complication. These findings support the clinical safety of both techniques when appropriate drug doses, ultrasound guidance, incremental injection, aspiration, monitoring, and standard precautions are used [17].

 

Patient satisfaction was high with both agents, with 94.0% of patients in the bupivacaine group and 92.0% in the ropivacaine group reporting overall satisfaction. The lack of a significant difference suggests that the longer duration of bupivacaine did not produce a substantial disadvantage from the patient's perspective during the observed period [18]. Both techniques therefore achieved the fundamental goals of regional anaesthesia: satisfactory intraoperative anaesthesia, good postoperative pain control, avoidance of general anaesthesia, and high patient acceptance [19].

 

The findings have practical implications for anaesthetic decision-making. Bupivacaine appears particularly useful when prolonged postoperative analgesia is a priority, such as after procedures expected to cause significant postoperative pain or when prolonged systemic analgesic-sparing effects are desired [20]. Ropivacaine, on the other hand, may be preferable when earlier motor recovery is considered important. Thus, selection should not be based solely on which drug produces the longest block; rather, the choice should be individualized according to surgical procedure, expected postoperative pain, need for early limb movement, and the desired duration of regional anaesthesia [21].

 

The use of ultrasound guidance is another important aspect of the present study. Ultrasound allows direct visualization of the brachial plexus and surrounding vascular and pleural structures and facilitates controlled deposition of the local anaesthetic [22]. Standardization of the technique and injection volume in both groups reduces procedural variability and strengthens the comparison between the two drugs. The absence of serious block-related complications in the present series further supports the feasibility of ultrasound-guided supraclavicular blockade in a tertiary-care hospital setting [23].

 

The study has certain limitations. It was conducted at a single tertiary-care institution with a relatively modest sample size of 100 patients, which may limit the generalizability of the findings. The study evaluated a single concentration and volume of each local anaesthetic; therefore, the results cannot necessarily be extrapolated to other concentrations, volumes, or adjuvant combinations [24]. Follow-up was focused on the perioperative and early postoperative period, and longer-term neurological outcomes were not specifically evaluated. In addition, the study included elective surgical patients with ASA I–II status, so the findings may not be directly applicable to patients with substantial systemic disease [25].

 

Overall, the findings demonstrate that both bupivacaine and ropivacaine are effective local anaesthetics for ultrasound-guided supraclavicular brachial plexus block. Bupivacaine provides a significantly longer sensory and motor block and prolonged postoperative analgesia with reduced early rescue analgesic requirement. Ropivacaine provides comparable onset and surgical anaesthesia but permits significantly earlier motor recovery. The clinically appropriate choice therefore depends on whether prolonged analgesia or early postoperative motor recovery is the predominant objective.

Both 0.5% bupivacaine and 0.5% ropivacaine provided effective and reliable ultrasound-guided supraclavicular brachial plexus blockade for elective upper-limb surgery. There was no significant difference in the onset of sensory or motor blockade, and both agents provided satisfactory surgical anaesthesia with stable perioperative haemodynamic parameters and a low incidence of adverse effects. Bupivacaine produced significantly longer sensory and motor blockade and significantly prolonged postoperative analgesia, resulting in lower early rescue analgesic requirements. Ropivacaine, in contrast, demonstrated significantly earlier motor recovery while maintaining comparable quality of surgical anaesthesia and postoperative pain control.

 

Thus, bupivacaine may be advantageous when prolonged postoperative analgesia and analgesic-sparing are the primary objectives, whereas ropivacaine may be preferable when early postoperative motor recovery and functional assessment are prioritized. Both agents remain effective options for supraclavicular brachial plexus block, with selection appropriately individualized according to the surgical procedure and desired postoperative recovery profile.

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