European Journal of Cardiovascular Medicine

Benign prostatic hyperplasia predominantly affects elderly men and frequently necessitates TURP. This patient population often has limited cardiovascular reserve, making anesthetic stability essential. Spinal anesthesia is widely preferred for TURP due to its ability to provide effective anesthesia while allowing early detection of complications such as bladder perforation and TURP syndrome.

A sensory level up to T10 is sufficient for TURP, ensuring adequate analgesia while minimizing excessive sympathetic blockade. Extending the block beyond this level may obscure early signs of capsular perforation. Therefore, reducing the dose of local anesthetic while supplementing it with adjuvants is a rational strategy to maintain adequate anesthesia with minimal hemodynamic disturbance.

Levobupivacaine, the S-enantiomer of bupivacaine, has a more favourable cardiovascular safety profile. Fentanyl, a lipophilic opioid, enhances intrathecal analgesia but may be associated with opioid-related adverse effects. Dexmedetomidine, a highly selective α2-adrenergic agonist, prolongs sensory and motor blockade through spinal receptor-mediated mechanisms and has emerged as a promising adjuvant.

This study was designed to compare the block characteristics, hemodynamic responses, and postoperative analgesic profile of dexmedetomidine and fentanyl when used intrathecally with levobupivacaine.

This prospective, randomized, double-blind study was conducted at two peripheral teaching hospitals in the combined district of Visakhapatnam, Andhra Pradesh between June 2025 and February 2026 after institutional approval and informed consent. Inclusion Criteria : Male patients aged 50–80 years ASA physical status I–III Scheduled for TURP Exclusion Criteria: Previous spinal surgery Coagulopathy Allergy to local anaesthetics Group Allocation: Group D (n=30): 2 mL (10 mg) 0.5% isobaric levobupivacaine + 0.5 mL (5 μg) dexmedetomidine Group F (n=30): 2 mL (10 mg) 0.5% isobaric levobupivacaine + 0.5 mL (25 μg) fentanyl The total injectate volume was standardized to 2.5 mL in both groups. Drug preparation was performed by an anaesthesiologist not involved in data collection. Intraoperative Monitoring: Standard monitoring included ECG, non-invasive blood pressure, and SPo₂. Baseline vitals were recorded. Preloading was performed with normal saline. Assessment Parameters 1)Block Characteristics Time to reach T10 sensory block Peak sensory level Time to two-segment regression Motor block (Modified Bromage scale) Time to complete motor recovery 2)Postoperative Pain Assessment VAS (0–10 scale) assessed every 2 hours up to 24 hours. Rescue analgesia: Butorphanol 1 mg IV. Time to first analgesic requirement recorded. 3)Adverse Events Bradycardia: HR < 45 bpm Hypotension: MAP < 60 mmHg Managed appropriately with atropine or mephenteramine. Statistical Analysis: Sample size was calculated based on previous literature to detect a 25% difference in sensory regression time (α=0.05, power=80%). Student’s t-test, Mann–Whitney U test, and Z-test were applied. P < 0.05 was considered statistically significant.

Demographic variables were comparable between groups.ASA physical status in both groups were comparable and there is no significant statistical difference between the two groups.

Table 1

The mean time taken to reach T10 sensory Block was (10.70 ± 2.24min) was lower in Group D than with Group F which was (11.8 ± 1.75min) which is comparable and statistically significant. Peak sensory Block levels were similar in both groups D & F while the maximum level of sensory block achieved in both groups was T8

Duration of two segment regression of sensory block was higher in Group D (125.833±9.88) and in Group F (120.7±5.20mins) was Significant (P=0.0146)

Motor Block lasted for a longer duration in Group D (197.033±12.71min) than in Group F (187.8±8.23 min) and it was statistically significant (p=0.0015).

Duration of first analgesic requirements with Group D (212.033±15.07min) while in Group F it in (200.667±7.44min) which is comparable and statistically significant (p=0.0005)

Group D patients had low postoperative VAS score and reduced analgesic requirements.

Intra operative Side Effects:

None of the patients developed severe Complications like severe hypotension (MAP < 60). While very few patients reported nausea and shivering which were treated with Inj. Ondansteron 4mg. None 

Transurethral Resection of prostate for benign prostatic hypertrophy is frequently performed in elder patients with cardiovascular comorbidities and systemic diseases. Considering this, it is desirable to limit the spinal block level to as low as possible to avoid hypotension owing to high sympathetic block and also maintain required level of anesthesia. For these reasons, local anesthetics combined with other drugs i.e,. an opioid (Fentanyl) or α- agonist (dexmedetomidine) have been used as adjuvants to provide synergestic analgesia and to reduce the dose of local anaesthetic used. Opioid like Fentanyl has been used as adjuvant most commonly nowadays to reduce the dose of intrathecal local anaesthetics and improve the block quality. However some adverse effects are associated with the use of opioids such as urinary retention, pruritus, nausea, vomiting and respiratory depression. It has been found that dexmedetomidine prolong the post operative analgesia of local anesthetics with less side effects and is a very promising adjuvant to improve the quality of spinal anesthesia. The comparative study was designed to evaluate the efficacy and characteristics of dexmedetomidine and fentanyl as adjuvants to local anesthetics during spinal anesthesia. In this comparative study dexmedetomidine significantly prolonged the duration of sensory and motor block compared with fentanyl. Also the time to achieve maximum sensory level was less though not significant in dexmedetomidine group. There was a longer pain free period and post operative analgesic requirement was late in Group D than Group F. In spite of certain biased hypothetication regarding pruritis there was no incidence of any pruritis or respiratory depression in any group. Coombs et al first introduced the analgesic properties of α2 adrenergic receptor agonist during intrathecal injection. Subsequent studies have shown that the injection of intrathecal α2adrenoceptoragonist is mainly achieved by inhibiting the release of C peptide transmitters and substance P and hyper polarizing post synaptic dorsal horn neurons and the analgesic effect has a good correlation with their binding affinity to the spinal α2 adrenergic receptors. Therefore dexmedetomidine as a highly selective α2adrenoceptor agonist (α2/ α1 1600:1) has greater advantage in intrathecal injection. However there are some dose related side effects of α2 agonist (dexmedetomidine) i.e sedation and neurotoxicity. The dose of Dexmedetomidine used in our study was at the end of dosing spectrum and didn’t produce any sedative effects. The greatest concern of dexmedetomidine is neurotoxicity. It can cause moderate to severe demyelination of white matter when it was administered by epidural route at a dose of upto 10μg/kg in rabbits However in an experiment with sheep dexmedetomidine (2.5-100μg) intrathecal injection did not cause neurological deficits In the systematic review by Abdallah and Brull doses of dexmedetomidine upto 0.2μglkg for intrathecal and lμg/kg for peripheral administration didn’t produce any neurotoxic manifestations Limitations of our Study : We could not perform a follow up for our patients to asses any signs of neurotoxicity or neurological deficits due to the use of dexmedetomidine in the study group

In conclusion when compared to fentanyl (25ug) we found that Dexmedetomidine (5μg) as adjuvant to 2cc of 0.5% isobaric levobupivacaine for intrathecal injection in TURP surgeries can statistically significantly prolong the duration of sensory and motor block as well as prolonged post-operative analgesia without significant hemodynamic changes

Acknowledgement :

Authors would like to acknowledge the guidance of our heads of departments in Andhra Medical College and Government Medical College Paderu,in conducting the study

Financial support and sponsorship:

Nil conflicts of interest .There are no conflicts of interest