Effectiveness Of Low-Dose Intermittent Epidural Bolus of 1 mg Morphine as Postoperative Analgesia

Background: Patients who have undergone major surgery typically experience postoperative pain that persists for seven days following surgery. The challenge for the anesthesiologist is to provide adequate postoperative pain control which is not always achievable. In contrast to systemic administration, epidural administration of opioids places the medications close to the site of action, allowing for relatively small doses to be effective with a low incidence of side effects. Morphine is a long-established analgesia drug that characteristically slows diffusion and long duration in epidural analgesia, making it widely used in postoperative pain management. However, giving morphine is not without any complications. Case Illustration: Nine patients who underwent major surgeries either under combined epidural-general anesthesia or epidural anesthesia received a low-dose intermittent epidural bolus of 1 mg morphine in 10 mL normal saline every 12 hours after surgery. Postoperative pain scores were recorded at the 1 st ,12 th ,24 th , 36 th , and 48 th hours after surgery, data of additional rescue analgesia, and the incidence of nausea, vomiting, pruritus, sedation, and respiratory depression were also collected. Only one patient needed rescue analgesia with 30 mg Ketorolac IV, and one patient needed anti-emetic with 4 mg ondansetron IV an hour after the completion of surgery. The rest of the patients have mild pain (NRS≤3/10) within 48 hours after surgery. Furthermore, there is no other adverse effects of morphine were found Conclusion: low dose intermittent epidural bolus of 1 mg morphine can be used as effective postoperative analgesia and has fewer adverse effects.


INTRODUCTION
As a result of the fact that many

CASE ILLUSTRATION
This case includes a preliminary study covering the serial case, hence during its preparation, applying for an ethics license is impossible.However, the researcher has provided informed consent for patients and families regarding publication of related data.A total of 12-14 mL of 0,5% plain bupivacaine was given as the initial  epidural morphine dose in the USA is 2.5-3.75mg.However, the ideal dose is not an "Asian optimal dose", due to their sensitivity to opioids.The ethnic differences in the μ-opioid receptor gene (OPRM1) break the balance between the conflicting demands of providing optimal analgesia while minimizing dose-related adverse effects.
Therefore, the epidural analgesia dose of morphine should be decreased and better, to begin with, 1-2 mg 10,11,12 .
In our case report, nine patients

CONFLICT OF INTEREST
The Authors declare that they have no conflict of interest.Science Insights, 2017( 5), 1-6 the epidural space.It plays a significant role in the alleviation of postoperative pain.In the past few decades, it has evolved as one of the major elements of the multimodal approach in accomplishing the goal of adequate and effective control of postoperative pain besides offering superior results in comparison with systemic opioids.It also reduces the unfavorable physiology experienced during the surgery.The presence of opioid receptors in the spinal cord allows the use of morphine epidurally for managing pain.
Hip Arthroplasty, Correction deformity of Hallux Valgus, and ORIF Plate and screw + Biopsy excision) Urologic surgery Vascular surgery 2 cases (Radical Nephrectomy, Percutaneous Nephrolithotomy) 1 case (Thrombectomy + Fasciotomy) Gusti Ayu Pitria Septiani, Dedi Fitri Yadi, Suwarman Effectiveness Of Low-Dose Intermittent Epidural Bolus of 1 mg Morphine as Postoperative Analgesia All patients received an intermittent epidural bolus of 1 mg morphine in 10 mL normal saline every 12 hours.The severity of pain was evaluated at 1, 12, 24, 36, and 48 hours after surgery with numerical rating scales (NRS, an 11point scale where 0= no pain and 10 = the worst pain).Additional data on rescue analgesia and incidence of opioid-related side effects such as nausea, vomiting, pruritus, sedation, One patient who underwent thrombectomy and fasciotomy of lower extremities have NRS 4/10 shorty after the epidural morphine is given, thus she received rescue analgetic with 30 mg Ketorolac IV.One patient developed insufficient pain control with NRS ≥4/10 within an hour after surgery, thus receiving rescue analgesia with 30 mg of Ketorolac intravenously.NRS intensity has decreased following further assessment by a range of 1/10-2/10.The pain scoring was listed in figure 1.

Figure 1 .
Figure 1.Post Operative pain score with NRS the bolus epidural was given, thus she received rescue analgetic with 30 mg Ketorolac IV.She only has one time of rescue analgesia and for the rest of the 48 hours, she continues to receive bolus 1 mg of epidural morphine as the severity of pain began to decrease, and no significant pain issue arises afterward.It is classified as breakthrough pain which refers to a temporary increase in pain to greater than moderate intensity, which typically peaks its severity within 3-5 minutes after onset and lasts for about 30 minutes.As we know, morphine is a hydrophilic opioid with slow diffusion and long-duration characteristics as an analgesia regimen.Because of its delayed onset of analgesia, this patient might experience breakthrough pain within less than 30 minutes due to receiving her first epidural bolus of 1 mg morphine just before being transferred to PACU. 13 Recent studies would indicate that it is possible to achieve better analgesia with lower doses of morphine epidurally.However, giving morphine is not without any complications, there are some adverse effects, such as PONV, pruritus, sedation, and in severe cases may induce early and late respiratory depression.From large retrospective and prospective database analyses, the incidence of respiratory depression is 0-2.8% for epidural morphine with dose ranges of 2-5 mg, and that adverse effect is not greater compared to systemic administration.Nausea and vomiting are common side effects experienced after abdominal and/or pelvic surgery.However, the incidence of these side effects is increased in patients treated with epidural opioids.The incidence requiring treatment has been reported to be approximately 25%, ranging from 22% to 29%.It has been suggested that postoperative nausea and vomiting may be due to stimulation of the chemoreceptor trigger zone either by the vestibular apparatus or by high concentrations of opioids in plasma or cerebrospinal fluid.Several alternative therapies, such as Droperidol (0.625-1.25 mg) and Metoclopramide (10 mg) given as prophylaxis or every 4-6 hours, be effective.Intractable nausea and vomiting can be treated with an intravenous bolus of naloxone, followed by a continuous infusion of 0.5 to 1.0 μg/kg/hr.Ondansetron has become popular due to its limited side effect profile.A 2-4 mg dose intravenously quickly reduces the severity of the symptoms that the patient may be experiencing. 14In our case series, only one patient reported nausea and vomiting an hour after the first dosage of 1 mg epidural morphine was given, be effective in treating prophylaxis pruritus.It is theorized that naloxone's antipruritic action arises mainly from the blockade of central enkephalinergic transmission.In our case series, no one of our nine patients developed pruritus.Sedation scale was assessed by the Ramsay sedation scale (1: alert and awake, 2: arousable to verbal command, 3: arousable with gentle tactile stimulation, 4: arousable with vigorous shaking, and 5: unarousable) and no oneof the patients has a score of more than 2 points.14,15The incidence of respiratory depression is classified as biphasic, with early (< 2 hours) dan Adjuvan pada Analgesi Epidural di Solo Journal of Anesthesi, Pain and Critical Care | Vol 3 No 2 October 2023 Medical Faculty of Universitas Sebelas Maret -PERDATIN Solo 121 Gusti Ayu Pitria Septiani, Dedi Fitri Yadi, Suwarman Effectiveness Of Low-Dose Intermittent Epidural Bolus of 1 mg Morphine as Postoperative Analgesia Wilayah Jawa Barat Tahun 2015.randomized controlled trial.

Table 1 . Demographic and perioperative data
pain).The occurrence of side effects (nausea, vomiting, pruritus, and sedation using the Ramsay Sedation Scale) and the uses and dosages of the other analgesic agents within 48 hours were also recorded.In the case of