European Journal of Cardiovascular Medicine

The International Association for the Study of Pain (IASP) defines pain as an unpleasant sensory and emotional experience that is associated with actual or potential tissue damage. The journey from agonizing surgeries to relatively painless procedures reflected a remarkable progression in medical science.

Since 1840’s various methods of anaesthesia were used by anaesthesiologists depending on the type of surgery and its duration, general condition of the patient, availability of needed resources and skill. They are general anaesthesia, spinal anaesthesia, total intravenous anaesthesia and peripheral nerve blocks.

Spinal anaesthesia has many advantages over general anaesthesia like awake patient, low drug costs and quick patient turnover. Lower abdominal and lower limb surgeries can be performed under either general anaesthesia or regional anaesthesia (spinal, epidural, or combined spinal epidural). Due to the sheer benefits, Spinal anaesthesia is preferred over general anaesthesia for infra umbilical surgeries like lower abdominal, lower limb, pelvic, and perineum surgeries.

After the discontinuation of intrathecal use of lidocaine (Produced permanent nerve injury and TNS – Transient Neurological Symptoms), 0.5 % Bupivacaine was the only drug routinely used for spinal anaesthesia. However, it has cardiotoxic and central nervous system side effects. So scientists have developed and found the benefits of bupivacaine’s two pure S (-) enantiomers: levobupivacaine and ropivacaine.

The less lipophilic ropivacaine is a long-acting amide local anaesthetic agent and so it is less likely to penetrate large myelinated motor fibres, which results in a relatively reduced motor blockade.

Levobupivacaine is also an S (-) enantiomer of the bupivacaine that has less CVS and CNS side effects. So it is well tolerated in a variety of regional anaesthesia techniques. Toxicity with levobupivacaine are very scarcely reported and those toxic symptoms are usually reversible in nature but still bupivacaine in clinical practice is not replaced by these two enantiomers.

 Levobupivacaine and ropivacaine were in use since 1980’s, but there are very few studies on their use in spinal anaesthesia for obstetric, lower abdominal and orthopaedic surgeries for both hyperbaric and isobaric forms.

This study was a hospital based prospective study to compare the efficacy of isobaric ropivacaine and isobaric levobupivacaine with fentanyl in spinal anaesthesia using onset of sensory and motor blockade, duration of sensory and motor blockade, haemodynamic changes and complications in patients under American Society of Anaesthesiologists (ASA) class 1 and II undergoing elective infraumbilical surgeries.

AIM AND OBJECTIVES

Aim: To compare the efficacy of isobaric Ropivacaine (0.75%) versus isobaric Levobupivacaine (0.5%) with fentanyl in elective infraumbilical surgeries.

Objectives: The primary objective of the study was to compare the efficacy of 3 ml of isobaric Ropivacaine (0.75%) (22.5 mg) and 3 ml of isobaric Levobupivacaine (0.5%) (15 mg) with fentanyl 0.3 ml (15mcg) in spinal anaesthesia, in terms of Onset of sensory and motor blockade, Duration of sensory and motor blockade, Alteration in Hemodynamics, Incidence of adverse effects and Requirement of additional analgesia. Further, the segmental height of sensory block was evaluated as the secondary objective.

Study design: Hospital based prospective comparative study.

Study Population: Patients undergoing Elective infraumbilical Surgeries during the study period in Government Medical College and Hospital, Cuddalore.

Study participants: Patients of age 18-60 years with ASA I & II

Study period: August 2023 to February 2025

Sample size: 60 patients divided into two groups of 30 each.

Inclusion criteria: Patients undergoing elective infraumbilical surgeries of age between 18 to 60 years in both sexes with BMI between 18 to 30 kg/m² classified under American Society of Anesthesiologists Physical Status Classification I & II.

Exclusion criteria: Patients with Spinal deformity, local infection, bleeding disorders, neurological disorders, cardiorespiratory disease, liver diseases, allergic to drugs used in the study and patient refusal.

PROCEDURE

After obtaining Ethical committee approval and assessing the patient in the assessment clinic, written informed consent was obtained from the selected patients using the inclusion and exclusion criteria. The patients were allocated into two groups of 30 each (Group L = 30 and Group R = 30). Then the patients were shifted to the operation theatre. Patients were connected to the monitor and their heart rate, saturation and blood pressure were monitored. Intravenous access was secured with 18G cannula and intravenous fluids at the rate of 70 ml/kg/hr was started.

Then under strict aseptic precautions, patients in lateral position subarachnoid block with 3ml of either Isobaric Levobupivacaine (0.5%) (15 mg) with fentanyl 0.3 ml (15mcg) for Group L patients or 3 ml of Isobaric Ropivacaine (0.75%) (22.5 mg) with fentanyl 0.3 ml (15mcg) for Group R patients was given using 23G spinal needle in L3-L4 space by an experienced anaesthetist. 22.5 mg of ropivacaine was used because it was considered 50 % less potent than bupivacaine or levobupivacaine by a study conducted by Gautier PE et al.^[38].

The onset of sensory block is the time from intra thecal injection to the loss of pinprick sensation at T10. The onset of motor block is the time to achieve a Bromage score 3 from the time of subarachnoid block. Bromage 0 – Full flexion of knees and feet. Bromage 1 –Able to move the knees. Bromage 2 – Able to move the feet only. Bromage 3 – unable to move the feet or knees. Heart rate, SPO2, Blood pressure were monitored at every 5 minute interval throughout the intraoperative period and in the postoperative period till bromage score was returned to Zero.

The two segment regression from maximum level of sensory block was assessed and considered as duration of sensory block for comparing the efficacy of the drugs. The duration of motor blockade was assessed by return of the Bromage score to zero. These were assessed at 15 minute intervals.

The maximum level of sensory block achieved was also recorded by assessing at two minute intervals from the onset of sensory block.

Any adverse events like Bradycardia, Hypotension, Nausea, Vomiting and Shivering was noted. Bradycardia was treated with injection Atropine 0.6 mg given intravenously. Hypotension was managed with injection Ephedrine 6 mg given intravenously. Nausea was treated with injection Ondansetron 0.1 mg/kg given intravenously. Patients with shivering were given Ondansetron 0.1 mg/kg and Tramadol 40 – 50 mg intravenously.

STATISTICAL ANALYSIS

The data collected were entered into Microsoft Excel and a master chart was created. The master chart was then loaded onto SPSS version 26 for statistical analysis.

Both quantitative and qualitative variables were present in the study. The quantitative variables were expressed using mean and standard deviation. The qualitative variables using frequency and percentages. To compare the mean between group L and group R, independent samples t test was used and to compare the distribution of qualitative variable between group L and group R, Chi square test was applied.

A ‘P’ value of less than 0.05 indicated statistical significance. Line graphs and bar diagrams were used to diagrammatically depict the results obtained

Distribution of age, weight, gender, BMI and procedure among the study groups.

Participants in the Levobupivacaine group were 35.25 ± 3.61 years old on average, whereas those in the Ropivacaine group were 38.19 ± 4.15 years old. Likewise, the mean weight of the Levobupivacaine and Ropivacaine groups was 64.51 ± 3.72 kg and 62.43 ± 4.64 kg, respectively. There were no significant differences between the groups' baseline characteristics.

Out of the total 60 participants, 18.33% in the Levobupivacaine group and 21.67% in the Ropivacaine group were females, while 31.67% and 28.33% were males respectively. The sex distribution was balanced across both groups, minimizing gender as a confounding factor in clinical outcomes.

Procedural types such as fissure, fistula, hernia, patella fracture, and tibia fracture were proportionately distributed across both groups. For example, fissure surgeries constituted 13.33% and 15% in Levobupivacaine and Ropivacaine groups, respectively. This uniformity in procedural types supports the internal validity of outcome comparisons.

Comparative Analysis of Onset of Sensory and Motor Blocks.

In the present study Levobupivacaine exhibited a significantly faster onset of both sensory (6.49 ± 3.19 min) and motor block (7.91 ± 3.64 min) compared to Ropivacaine (8.43 ± 3.67 min and 11.13 ± 3.11 min, respectively).

 Samar P et al. reported similar results: group L experienced a substantially faster mean onset of sensory block (6.97 ±1.82 mins) than group R (8.47 ±2.55 mins), p<0.05, and group L experienced a significantly faster mean onset of motor block (10.27 ±1.92 mins) than group R (12.93 ±2.55 mins), p<0.05^[1].  

The mean time to start the sensory block was 4.32 ± 1.51 minutes in Group LD and 7.24 ± 1.5 minutes in Group RD, according to a study by Bhagyesh Sushchendra Kame et al. The mean time for onset of sensory block {T10} was significantly longer in the Ropivacaine group than in the Levobupivacaine group. Group LD's motor block onset time was 4.5 ± 1.85 minutes, while Group RD's was 5.74 ± 2.26 minutes. This was much longer than Group RD's^[2].

Comparative Analysis of Duration of Sensory and Motor Blocks.

In our study, the duration of sensory block (119.62 ± 4.09 min vs. 89.17 ± 2.69 min) and motor block (181.40 ± 4.74 min vs. 151.15 ± 4.97 min) was significantly longer in the Levobupivacaine group (p < 0.001).

Similar results were in the study by Samar P et al., the mean duration of sensory block in group L (147.63 ±27.53 mins) was significantly longer than in group R (97.40 ±12.38 mins), p<0.05 and the mean duration of motor block in group L (207.33 ±22.27 mins) was significantly longer than in group R (146.60 ±21.22 mins), p<0.05^[1].

According to a study by Bhagyesh Sushchendra Kame et al., Group LD had a significantly higher mean time for two segment regressions from the highest sensory level (115.59 ± 11.33) against Group RD (92.65 ± 11.09), and Group LD had a significantly longer mean duration of motor blockade (393.53 ± 25.33) than Group RD (267.35 ± 23.78)^[2].

Comparison of Maximum Sensory Blockade Level Achieved Between Study Groups

In the present study the peak sensory level achieved was mostly at T6 in both groups 26.67% in Levobupivacaine and 30% in Ropivacaine. Fewer patients reached T4 (10% and 3.33% respectively), suggesting slightly higher cephalad spread in the Levobupivacaine group.

Study by Oraon P et al. found that 66.66% of the patients receiving hyperbaric bupivacaine achieved T4 level as the highest sensory block, while in the isobaric levobupivacaine group, 20% of patients achieved T4 level and only 6.66% of the patients in the isobaric ropivacaine group achieved T4 level as the highest level of sensory block^[4].

Comparison of Mean Systolic and Diastolic Blood Pressure Over Time Between Levobupivacaine and Ropivacaine Groups

 In the present study throughout the intraoperative monitoring period (5 to 240 minutes), SBP values were slightly higher in the Ropivacaine group. However, none of the time-point comparisons reached statistical significance (p > 0.05). Statistically significant differences were observed at multiple time points (5, 10, 60–240 minutes) with p < 0.05, where Levobupivacaine consistently maintained higher DBP values compared to Ropivacaine.

However in the study by Samar P et al., the results obtained were different from the current study. Group R had a lower mean intraoperative SBP among the two groups at 2, 5, 10, 15, 20, 25, 30, 45, 60, 75, and 90 minutes. This difference in mean intraoperative SBP was statistically significant (p0.05). The difference in mean intraoperative DBP between two groups at each interval was not significant (p>0.05)^[1].

Comparison of Adverse effects between Levobupivacaine and Ropivacaine Groups

In our study, both groups demonstrated a low and comparable incidence of side effects such as bradycardia, hypotension, nausea, and shivering. Interestingly, a slightly higher proportion of participants experienced no side effects in the Levobupivacaine group (36.67%) than in the Ropivacaine group (33.33%).

In the study by Samar P et al., similar results were obtained. Complications were lower in patients who received levobupivacaine (13.3%) as compared to those who received ropivacaine (40%)^[1].

But different result was obtained in the study by Jain S et al., Bradycardia (6.7%) was higher in levobupivacaine group in comparison to 3.3% in ropivacaine group^[33].

Comparison of rescue analgesia needed in both groups

 In the present study only 3.33% in the Levobupivacaine group and 6.67% in the Ropivacaine group required additional analgesia, indicating that both agents provided effective anaesthesia for the duration of surgery.

Sriramka et al. showed that the LD group required more rescue analgesia and that the analgesia duration was slightly longer (955.3 ± 114.5 minutes) than the RD group (894.6 ± 91.3), with a p-value of 0.027^[37].

Limitations of the study

 The study was done for various surgical procedures which require different level of anaesthesia and varying duration of the procedure. The study doesn’t involve a large proportion of the population. So a double blinded study involving a large sample size in a single type of surgical procedure is needed to evaluate and compare the efficacy of these two drugs.

SUMMARY

For elective infraumbilical surgeries (lower abdominal, inguinal, perennial and lower limb surgeries), Spinal anaesthesia is the preferred method of choice when compared to general anaesthesia

The groups were comparable in baseline characteristics with no major disparities, suggesting appropriate randomization.

Out of the total 60 participants, the sex distribution was balanced across both groups, minimizing gender as a confounding factor in clinical outcomes.

In this study Levobupivacaine exhibited a significantly faster onset of both sensory and motor block compared to Ropivacaine. The duration of sensory block and motor block was significantly longer in the Levobupivacaine group.

 In this study the peak sensory level achieved was mostly at T6 in both groups with slightly higher cephalad spread in the Levobupivacaine group.

In the current study both agents maintained a stable systolic BP without clinically relevant fluctuations and Levobupivacaine consistently maintained higher DBP values compared to Ropivacaine.

Both groups demonstrated a low and comparable incidence of side effects such as bradycardia, hypotension, nausea, and shivering. A slightly higher proportion of participants experienced no side effects in the Levobupivacaine group than in the Ropivacaine group. These results confirm the safety and tolerability of both drugs, with Levobupivacaine showing a marginally better profile.

This study was done to compare the efficacy of 3-ml 0.5% isobaric levobupivacaine and 3-ml 0.75% isobaric ropivacaine with fentanyl in subarachnoid block for elective infraumbilical surgeries. We can conclude that when compared to Ropivacaine, Levobupivacaine had a faster onset of both sensory and motor block, and the Levobupivacaine group experienced sensory and motor block for a noticeably longer duration of time. Both groups demonstrated a low and comparable incidence of adverse effects.