European Journal of Cardiovascular Medicine

Spinal anesthesia is a common anesthetic technique used for a variety of surgical procedures, particularly in the lower abdomen, pelvis, and lower extremities. It offers several advantages, including rapid onset, effective sensory and motor blockade, and minimal respiratory depression. However, spinal anesthesia is not without risks and can be associated with several adverse events, such as hypotension, bradycardia, and postoperative nausea and vomiting (PONV) [1].

The choice of anesthetic agent plays a crucial role in the occurrence and severity of these adverse events. Bupivacaine, ropivacaine, and levobupivacaine are among the most frequently used local anesthetics for spinal anesthesia. Each of these agents has a unique pharmacological profile that influences their safety and efficacy. Bupivacaine is known for its potent and long-lasting effects but is also associated with a higher incidence of cardiovascular adverse events [2]. Ropivacaine, a relatively newer agent, has a similar efficacy profile to bupivacaine but is considered to have a better safety profile, particularly concerning cardiac toxicity [3]. Levobupivacaine, the S-enantiomer of bupivacaine, offers a comparable anesthetic effect with potentially fewer adverse cardiovascular effects [4].

Despite the widespread use of these agents, there is a need for comprehensive studies comparing their adverse event profiles in real-world clinical settings. Such data are essential for informed decision-making and optimizing patient care. This study aims to fill this gap by comparing the incidence and types of adverse events associated with bupivacaine, ropivacaine, and levobupivacaine used for spinal anesthesia in a tertiary care hospital.

The primary objective of this study was to compare the overall incidence of adverse events associated with the three spinal anesthesia techniques. Secondary objectives included identifying specific adverse events and their frequencies, as well as determining any patient-related factors that may predispose individuals to these events. By providing a detailed analysis of adverse event profiles, this study aims to guide anesthesiologists in selecting the most appropriate spinal anesthesia technique, ultimately enhancing patient safety and outcomes.

Study Design and Setting

This prospective, observational study was conducted at SRM Medical College Hospital, Bhawanipatna, Odisha, India. The study was approved by the institutional ethics committee, and written informed consent was obtained from all participants.

Study Population

The study included 180 adult patients (aged 18-65 years) scheduled for elective surgeries under spinal anesthesia. Patients with contraindications to spinal anesthesia, known allergies to local anesthetics, or significant co-morbid conditions (e.g., severe cardiovascular or neurological disorders) were excluded.

Randomization and Interventions

Patients were randomly assigned to receive one of three spinal anesthesia techniques: bupivacaine (Group B), ropivacaine (Group R), or levobupivacaine (Group L). The randomization was done using a computer-generated sequence, and the allocation was concealed until the patient was prepared for anesthesia.

Anesthetic Technique

Standard monitoring (ECG, non-invasive blood pressure, and pulse oximetry) was applied to all patients. Spinal anesthesia was performed at the L3-L4 or L4-L5 interspace using a 25-gauge Quincke spinal needle. The anesthetic solutions were prepared as follows:

• Group B: 0.5% bupivacaine, 3 mL
• Group R: 0.75% ropivacaine, 3 mL
• Group L: 0.5% levobupivacaine, 3 mL

Data Collection

Data on patient demographics, baseline clinical characteristics, and intraoperative and postoperative adverse events were collected. Adverse events were categorized as follows:

• Hypotension: Defined as a systolic blood pressure drop of more than 20% from baseline or a systolic blood pressure less than 90 mmHg
• Bradycardia: Defined as a heart rate less than 50 beats per minute
• PONV: Any occurrence of nausea or vomiting within 24 hours postoperatively
• Other events: Including headache, urinary retention, and neurological symptoms

Statistical Analysis

Data were analyzed using SPSS version 25.0. Descriptive statistics were used to summarize patient characteristics and adverse event frequencies. Chi-square tests were used to compare the incidence of adverse events between groups. Logistic regression analysis was performed to identify predictors of adverse events. A p-value of <0.05 was considered statistically significant.

Patient Characteristics

The demographic and baseline clinical characteristics of the study population are summarized in Table 1. The three groups were comparable in terms of age, gender, ASA classification, and baseline blood pressure.

Incidence of Adverse Events

The overall incidence of adverse events was 32.8%, with significant differences observed between the groups (p=0.041). The highest incidence was noted in the bupivacaine group (38.3%), followed by the ropivacaine (30.0%) and levobupivacaine (27.8%) groups. The most common adverse events were hypotension (15.0%), bradycardia (10.6%), and PONV (7.2%) (Table 2).

Comparison of Adverse Events

Significant differences were found between the groups regarding the incidence of hypotension and bradycardia. The bupivacaine group had a higher incidence of hypotension (21.7%) compared to ropivacaine (11.7%) and levobupivacaine (11.1%) (p=0.021). Similarly, bradycardia was more frequent in the bupivacaine group (16.7%) compared to ropivacaine (8.3%) and levobupivacaine (6.7%) (p=0.034). The incidence of PONV did not differ significantly between groups (p=0.621) (Table 3).

Additional Analyses

Further analyses were conducted to explore the impact of demographic factors and baseline clinical characteristics on the incidence of adverse events. Multivariate logistic regression identified age (OR=1.05, 95% CI: 1.01-1.09, p=0.014), baseline hypertension (OR=2.19, 95% CI: 1.25-3.84, p=0.006), and type of spinal anesthesia (bupivacaine vs. others) (OR=1.97, 95% CI: 1.14-3.41, p=0.015) as significant predictors of adverse events. These findings suggest that older patients and those with pre-existing hypertension are at higher risk for adverse events, and bupivacaine use may further increase this risk.

Table 1: Demographic and Baseline Clinical Characteristics of the Study Population

Table 2: Overall Incidence of Adverse Events

Table 3: Comparison of Adverse Events by Spinal Anesthesia Type

This study provides a comparative analysis of the adverse events associated with different spinal anesthesia techniques in a tertiary care hospital setting. The findings highlight significant differences in the incidence of adverse events among the three anesthetic agents—bupivacaine, ropivacaine, and levobupivacaine—used for spinal anesthesia.

The overall incidence of adverse events was found to be 32.8%, with the highest frequency observed in the bupivacaine group (38.3%). This finding aligns with previous studies that have reported a higher incidence of cardiovascular adverse events associated with bupivacaine due to its potent and long-lasting effects [2]. In contrast, ropivacaine and levobupivacaine demonstrated a lower incidence of adverse events, which may be attributed to their better safety profiles, particularly in terms of cardiac toxicity [3, 4].

Hypotension and bradycardia were the most common adverse events observed in this study. The incidence of hypotension was significantly higher in the bupivacaine group compared to the other groups. This can be explained by the potent vasodilatory effects of bupivacaine, which can lead to significant drops in blood pressure [9]. Ropivacaine and levobupivacaine, while still causing hypotension, did so at a lower frequency, likely due to their differential effects on sodium and potassium channels, which result in less vasodilation [10, 11].

Bradycardia was also more frequently observed in the bupivacaine group, which is consistent with its known side effect profile. The mechanism underlying bupivacaine-induced bradycardia involves its effect on the autonomic nervous system, leading to enhanced vagal tone and reduced sympathetic activity [12]. In contrast, ropivacaine and levobupivacaine have been shown to have less pronounced effects on heart rate, which is reflected in the lower incidence of bradycardia in these groups [13, 14].

Postoperative nausea and vomiting (PONV) were observed in 7.2% of the patients, with no significant differences between the groups. This finding is consistent with the general literature on spinal anesthesia, where PONV is a common but non-specific adverse event that can be influenced by multiple factors, including the type of surgery, patient susceptibility, and the use of adjunct medications [15].

The additional analyses revealed that age and baseline hypertension were significant predictors of adverse events, with older patients and those with pre-existing hypertension being at higher risk. These findings are important as they highlight the need for personalized anesthetic care, where patient-specific factors are considered when choosing the type of spinal anesthesia to minimize the risk of adverse events [16, 17].

In conclusion, this study underscores the differences in adverse event profiles among bupivacaine, ropivacaine, and levobupivacaine when used for spinal anesthesia. Levobupivacaine appears to offer a safer profile with fewer adverse events, making it a potentially better choice for patients, especially those with higher risk factors. However, the choice of anesthetic should always be tailored to individual patient needs and clinical scenarios. Further research with larger sample sizes and multicenter trials is needed to confirm these findings and provide more definitive guidelines for clinical practice.

This study provides a comparative analysis of the adverse events associated with different spinal anesthesia techniques in a tertiary care hospital setting. The findings highlight significant differences in the incidence of adverse events among the three anesthetic agents—bupivacaine, ropivacaine, and levobupivacaine—used for spinal anesthesia.

The overall incidence of adverse events was found to be 32.8%, with the highest frequency observed in the bupivacaine group (38.3%). This finding aligns with previous studies that have reported a higher incidence of cardiovascular adverse events associated with bupivacaine due to its potent and long-lasting effects [2]. In contrast, ropivacaine and levobupivacaine demonstrated a lower incidence of adverse events, which may be attributed to their better safety profiles, particularly in terms of cardiac toxicity [3, 4].

Hypotension and bradycardia were the most common adverse events observed in this study. The incidence of hypotension was significantly higher in the bupivacaine group compared to the other groups. This can be explained by the potent vasodilatory effects of bupivacaine, which can lead to significant drops in blood pressure [9]. Ropivacaine and levobupivacaine, while still causing hypotension, did so at a lower frequency, likely due to their differential effects on sodium and potassium channels, which result in less vasodilation [10, 11].

Bradycardia was also more frequently observed in the bupivacaine group, which is consistent with its known side effect profile. The mechanism underlying bupivacaine-induced bradycardia involves its effect on the autonomic nervous system, leading to enhanced vagal tone and reduced sympathetic activity [12]. In contrast, ropivacaine and levobupivacaine have been shown to have less pronounced effects on heart rate, which is reflected in the lower incidence of bradycardia in these groups [13, 14].

Postoperative nausea and vomiting (PONV) were observed in 7.2% of the patients, with no significant differences between the groups. This finding is consistent with the general literature on spinal anesthesia, where PONV is a common but non-specific adverse event that can be influenced by multiple factors, including the type of surgery, patient susceptibility, and the use of adjunct medications [15].

The additional analyses revealed that age and baseline hypertension were significant predictors of adverse events, with older patients and those with pre-existing hypertension being at higher risk. These findings are important as they highlight the need for personalized anesthetic care, where patient-specific factors are considered when choosing the type of spinal anesthesia to minimize the risk of adverse events [16, 17].

In conclusion, this study underscores the differences in adverse event profiles among bupivacaine, ropivacaine, and levobupivacaine when used for spinal anesthesia. Levobupivacaine appears to offer a safer profile with fewer adverse events, making it a potentially better choice for patients, especially those with higher risk factors. However, the choice of anesthetic should always be tailored to individual patient needs and clinical scenarios. Further research with larger sample sizes and multicenter trials is needed to confirm these findings and provide more definitive guidelines for clinical practice.

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