A randomized controlled study between fentanyl and Butorphanol with low dose intrathecal bupivacaine to facilitate early postoperative ambulation in urological procedures.

INTRODUCTION: Opioids are widely used in conjunction with local anesthetics as they permit the use of lower dose of local anesthetics while providing adequate anesthesia and analgesia. It both provides adequate anesthesia as well as lower drug toxicity neuraxial administration of opioids in conjunction with local anesthetics improves the quality of intraoperative analgesia and prolongs the duration of postoperative analgesia. Bupivacaine is the most commonly used drug for subarachnoid block due to its lesser side effects. The present study was conducted to decrease the overall dose of local anesthetics with opioid combination for urological procedure with respect to quality of anesthesia and recovery with patient's satisfaction.
MATERIALS AND METHODS: The study population was randomly allocated by computer generated table into two groups; Group A: 5 mg 0.5% bupivacaine + 25 mcg and Group B: 5 mg 0.5% bupivacaine + 25 mg butorphanol.
RESULTS: Highest level of sensory block was T9 and T8 with the fentanyl group and butorphanol group, respectively. The onset of sensory block was early in fentanyl group than butorphanol group. Duration of both sensory and motor block was significantly higher in butorphanol group. There was no incidence of itching in both groups. There were two patients in fentanyl group and one in butorphanol with hypotension for which injection mephentermine was given. Two patients in fentanyl group complained of nausea and vomiting, for which injection ondansetron was given. One patient complained of pain in fentanyl group for which injection propofol with injection fentanyl was supplemented.
CONCLUSION: Low-dose bupivacaine with butorphanol group was devoid of any side effects in the present study but low dose bupivacaine in addition with fentanyl is superior in terms of early postoperative recovery resulting in early discharge and better outcome in comparison to bupivacaine and butorphanol group, which is beneficial in elderly patients with comorbidity.

RCT Entities:   Population Interventions Outcomes

INTRODUCTION

Opioids are widely used in conjunction with local anesthetics as they permit the use of a lower dose of local anesthetics while providing adequate anesthesia and analgesia. It both provides adequate anesthesia as well as lower drug toxicity. The first published report on opioids for intrathecal anesthesia belongs to a Romanian surgeon, Racoviceanu-Pitesti, who presented his experience at Paris in 1901.[1] It is more than a century now, and use of opioids intrathecally is extensive nowadays. It has been well documented that the combination of opiates and local anesthetics administered intrathecally has a synergistic analgesic effect.[2] The addition of opioids has a more extensive role in a scenario where minimization of adverse effects of subarachnoid block is needed as in elderly and patients with coexisting comorbid conditions. Neuraxial administration of opioids in conjunction with local anesthetics improves the quality of intraoperative analgesia and prolongs the duration of postoperative analgesia.[34] Bupivacaine is the most commonly used drug for subarachnoid block due to its lesser side effects.[56] Various studies have shown that low-dose diluted bupivacaine with fentanyl can provide sufficient anesthesia with rapid recovery in patients undergoing ambulatory surgery or minor urological surgeries.[789] Fentanyl in combination with local anesthetics prolongs sensory anesthesia without prolonging recovery of motor function or time to micturition.[1011]

Butorphanol is a lipophilic opioid, has been used for epidural analgesia as well as intrathecal administration.[12131415] In a study by Singh et al. have shown that butorphanol is better than fentanyl-bupivacaine combination in respect to the duration of sensory blockade and requirement of rescue analgesia without any significant increase in adverse effects.[13] Dose used was bupivacaine 12.5 mg in both groups in the study.[13] In a similar study by Kumar et al. concluded bupivacaine and butorphanol combination superior in terms of duration and analgesia in comparison to bupivacaine and fentanyl combination with dosing of bupivacaine 12.5 mg in both the groups.[15] The present study was conducted to decrease the overall dose of local anesthetics with the opioid combination for the urological procedure with respect to quality of anesthesia and recovery with patient's satisfaction.

MATERIALS AND METHODS

The present study was conducted in Indira Gandhi Institute of Medical Sciences, Patna after approval from the Institutional Ethical Committee. Informed written consent was obtained from all patients after explaining the procedure. Sixty patients of American Society of Anesthesiologists Grade I and II between 18 and 65 years of age of either sex, scheduled for the elective urological procedure was included in this study.

The preanesthetic check-up included a detailed medical and surgical history, and any previous anesthetic exposure with its outcome. General examination includes general condition, built, weight, pulse rate, blood pressure, respiratory rate, and presence of cyanosis, anemia, clubbing, jaundice or edema. A careful thorough systemic examination was done to rule out any cardiovascular, respiratory, gastrointestinal, and neurological or any other systemic illness. Routine biochemistry investigation included hemoglobin, total leukocyte count, differential leukocyte count, blood sugar, blood urea, and serum creatinine, was done in all patients. Echocardiogram (ECG) and X-ray chest was done in patients where indicated and in those over 40 years of age along with other relevant investigation.

Patients with hemorrhagic diathesis, peripheral neuropathy, psychiatric disorders, allergy to local anesthetics and patients on opioid therapy/analgesics were excluded from the study.

Standard monitoring was used, including noninvasive arterial blood pressure, ECG, heart rate (HR), and pulse oximetry oxygen saturation (SpO2).

The study population was randomly allocated by computer generated table into two groups; Group A: 5 mg 0.5% bupivacaine + 25 mcg fentanyl and Group B: 5 mg 0.5% bupivacaine + 25 mg butorphanol.

On arrival to operation theater, routine monitoring was started and baseline vital parameters of HR, systemic arterial pressure including systolic, diastolic and mean arterial pressure, arterial SpO2, and ECG were recorded. An intravenous (IV) line was secured, and Ringer lactate was given at a rate of 6–8 ml/kg. All patients received premedication of IV injection midazolam (0.02 mg/kg) and injection glycopyrrolate (0.01 mg/kg). The solution was made to 2 ml by addition of normal saline to make the two groups comparable. Under all aseptic and antiseptic precautions lumbar puncture was performed in sitting position in L3–L4 space by an anesthesiologist blinded to the study. The anesthesiologist performing block recorded baseline vitals, every 3 min for first 15 min, and then every 5 min intraoperative until patient discharged from post anaesthesia care unit (PACU).

Hypotension was defined as systolic blood pressure of <90 mm of Hg or a decrease of more than 30% from baseline mean arterial pressure, injection Mephentermine 6 mg IV in incremental dose if required. Bradycardia (HR < 60 bpm) was treated with IV atropine.

Sensory dermatome level was assessed by pinprick and recorded with respect to onset, level, duration, and recovery. Motor level was assessed by using modified bromage score in terms of onset, level, duration, and recovery. Injection fentanyl and injection propofol was used for rescue analgesia in inadequate block, regarded as failure.

Modified bromage scale

0: No paresis – full movements of lower limbs

Partial paresis – flex knees and ankles

2: Partial paresis – flex ankles

3: Partial paresis – flex toes only

4: Full paresis – no movement.

Ramsay sedation score

Anxious or restless or both

Cooperative, orientated, and tranquil

Responding to commands

Brisk response to stimulus

Sluggish response to stimulus

No response to stimulus.

RESULTS

There were thirty patients in each group, assigned as Group A and Group B. Groups were demographically comparable in terms of age, sex, weight, and duration of surgery [Table 1].

Table 1

Demographic variables

The study results regarding the characteristics of the block are summarized in [Table 2]. There was no difference between or in the time to reach peak level (7.0 and 7.2 min, respectively). The highest level of sensory block was T9 and T8 with the fentanyl group and butorphanol group, respectively. The onset of sensory block was early in fentanyl group than butorphanol group. Duration of both sensory and motor block was significantly higher in butorphanol group. Adverse effects were accounted in both the groups as shown in Table 3 There was no incidence of itching in both groups. There were two patients in fentanyl group and one in butorphanol with hypotension for which injection mephentermine was given. Two patients in fentanyl group complained of nausea and vomiting, for which injection ondansetron was given. One patient complained of pain in fentanyl group for which injection propofol with injection fentanyl was supplemented.

Table 2

Block characteristics

Table 3

Adverse effects

CONCLUSION

Low-dose bupivacaine with Butorphanol group was devoid of any side effects in the present study but low dose bupivacaine in addition with fentanyl is superior in terms of early postoperative recovery resulting in early discharge and better outcome in comparison to bupivacaine and butorphanol group, which is beneficial in elderly patients with comorbidity.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.