|Year : 2015 | Volume
| Issue : 1 | Page : 107-113
Does tramadol or bupivacaine intraincisional infiltration with inguinal canal block during hernioplasty change the postoperative pain profile?
Gamal Musstafa, Ahmed A Badawy, Ahmed El-sakka, Amr Wahdan
Department of Anesthesia, Faculty of Medicine, Cairo University, Cairo, Egypt
|Date of Submission||31-May-2014|
|Date of Acceptance||06-Nov-2014|
|Date of Web Publication||25-Mar-2015|
Department of Anesthesia, Faculty of Medicine, Cairo University, Cairo
Source of Support: None, Conflict of Interest: None
The study aimed to evaluate the effect of inguinal canal block together with intraincisional injection of tramadol against bupivacaine 0.25% on both intraoperative and postoperative pain relief in patients undergoing inguinal hernioplasty under general anesthesia.
Patients and methods
The study was conducted on 60 male patients scheduled for elective inguinal hernioplasty under general anesthesia in the Kasr Al-Ainy School of Medicine. Patients were randomly allocated into three groups: group C [control group (n = 20)], group B [bupivacaine 0.25% group (n = 20)], and group T [tramadol group (n = 20)]. During the surgery, the mean arterial blood pressure and the heart rate were traced every 5 min. The total intraoperative fentanyl requirement, postoperative visual analogue score and sedation scores, and nausea and vomiting were recorded; patient and surgeon satisfaction were assessed.
The intraoperative mean arterial blood pressure, heart rate, and fentanyl requirement were statistically lower in both the bupivacaine and the tramadol groups compared with the control group. The postoperative visual analogue score was statistically lower in both the bupivacaine and the tramadol groups compared with the control group. Postoperative nausea and vomiting were statistically higher in the tramadol group compared with the control group and the bupivacaine groups. The scoring of postoperative patient satisfaction was statistically higher in the tramadol group compared with the bupivacaine and the control groups.
The study offered a new technique using tramadol as a locally infiltrated drug during inguinal hernioplasty aiming to decrease intraoperative and postoperative pain together with reducing analgesic needs to minimum during and after the operation with the consequent beneficial reduction of narcotic side effects.
Keywords: bupivacaine, inguinal hernioplasty, postoperative pain relief, tramadol
|How to cite this article:|
Musstafa G, Badawy AA, El-sakka A, Wahdan A. Does tramadol or bupivacaine intraincisional infiltration with inguinal canal block during hernioplasty change the postoperative pain profile?. Ain-Shams J Anaesthesiol 2015;8:107-13
|How to cite this URL:|
Musstafa G, Badawy AA, El-sakka A, Wahdan A. Does tramadol or bupivacaine intraincisional infiltration with inguinal canal block during hernioplasty change the postoperative pain profile?. Ain-Shams J Anaesthesiol [serial online] 2015 [cited 2021 May 6];8:107-13. Available from: http://www.asja.eg.net/text.asp?2015/8/1/107/153951
| Introduction|| |
Inguinal hernias are considered as the most common primary true hernias and their incidence is estimated to be 3% in women and 27% in men in a lifetime  . Inguinal hernia repairs are the most common procedures performed all over the world , . Patients undergoing abdominal surgeries need a multimodal intraoperative and postoperative pain treatment regimen aiming to provide high-quality analgesia with the lowest side effects. Opioids, such as morphine, remain the cornerstone of postoperative analgesic regimens in patients after abdominal surgery. Because of the significant adverse effects of opioids, alternative approaches, are required  . Side effects ranging from pruritus, nausea, and vomiting to more considerable effects such as sedation and respiratory depression may occur as a result of systemic administration of high doses of opiates. Subcutaneous administration of opiates might be a good alternative method for postoperative pain control in hernioplasty. A peripheral mechanism for opioid analgesia is investigated. Endogenous opioid-like substances released by immune cells infiltrating the inflammation site act on the opioid receptors found on the primary sensory neuron  . The use of pre-emptive local anesthetics is recommended to block central sensitization. The subcutaneous route has the advantages of avoiding first-pass metabolism, improved patient comfort, and good analgesia  . Clinical and laboratory studies demonstrated the local anesthetic effects of opioids  . Tramadol, a selective μ-receptor agonist, has been recently proven to have a local anesthetic effect on peripheral nerves , .
Tramadol is a racemic compound consisting of two isomers  . It causes both opioid system and nonopioid system activation, thus causing pain inhibition  . The nonopioid effect of tramadol is postulated to be mediated through α2-agonistic and serotonergic activities, inhibiting the reuptake of norepinephrine and hydroxyltryptamine, with the possibility of displacing stored hydroxytryptamine from the nerve endings  . Bupivacaine, which is a local anesthetic that blocks the generation and the conduction of nerve impulses, is commonly used for analgesia by infiltration of surgical incisions and has a longer duration than lidocaine  .
The aim of the present study was to determine whether using locally infiltrated tramadol or bupivacaine can afford adequate postoperative analgesia, thus obviating the need for large-dose opioids and avoiding narcotic side effects, and thus facilitate early ambulation and discharge.
| Patients and methods|| |
After approval by the local ethical committee and obtaining informed written consents from patients, this randomized controlled double-blinded study was conducted on 60 male patients, ASA physical status I, II with age between 20 and 50 years, scheduled for elective inguinal hernioplasty under general anesthesia in the Kasr Al-Ainy Hospital over a period of 6 months starting from October 2013. Patients were excluded from this study if they had an ASA physical status III-IV, BMI above 35 kg/m 2 , a history of relevant drug allergy, coagulation disorder, opioid tolerance, bronchial asthma, or had a history of analgesic intake within the last 24 h. Patients were randomly allocated into three equal groups of 20 patients each using a computer-generated number, and concealed using the sequentially numbered, sealed opaque envelope technique. The injection fluid was prepared by operation-theatre nurses, according to the closed-envelope data. All the staff members inside the theater were blinded to the prepared study drugs and it was disclosed only in case of an emergency situation.
Group C [control group (n = 20)]: Inguinal canal block and intraincisional infiltration were performed using a 20 ml solution of normal saline 0.9%.
Group B [bupivacaine 0.25% group (n = 20)]: Inguinal canal block and intraincisional infiltration were performed using a 20 ml solution of bupivacaine 0.25% concentration (0.7 mg/kg).
Group T [tramadol group (n = 20)]: Inguinal canal block and intraincisional infiltration were performed using tramadol 1 mg/kg. Drugs were diluted with sterile normal saline to yield 20 ml solution.
One day before the surgery, the intraincisional infiltration and the inguinal canal block were explained to the patients by both the surgeon and the anesthesiologist. Patients were also instructed about the evaluation of postoperative pain using the visual analogue scoring (VAS) system.
Preoperative assessment: All patients were assessed clinically and investigated for the exclusion of any of the above-mentioned exclusion criteria. The following laboratory work were carried out: a complete blood count, the prothrombin time and prothrombin concentration, the partial thromboplastin time, the bleeding time, the clotting time, liver function tests, and kidney function tests. On arrival to the operating theatre, the standard monitors were attached to the patients, including an ECG, pulse oximetry, and noninvasive blood pressure monitors, and preinduction baseline readings were noted. The induction of anesthesia was carried out with intravenous propofol (2 mg/kg) and fentanyl bolus doses (0.5 μg/kg). After unconsciousness was confirmed, an intravenous injection of 0.5 mg/kg of atracurium was administered, and after confirming that the muscle relaxation was sufficient, a laryngeal mask was inserted and the patients were ventilated mechanically (maintaining the peak airway pressure <25 cmH 2 O). Anesthesia was maintained by an isoflurane concentration equivalent to 1 MAC and 100% O 2 with a total fresh gas flow of 3 l/min. The end-tidal carbon dioxide partial pressure was maintained within the range of 30-40 mmHg. Fentanyl bolus doses (0.5 μg/kg) were adjusted to maintain the heart rate (HR) and the mean arterial blood pressure (MAP) within 20% of the preinduction values. Atracurium was given every 20 min (0.1 mg/kg). With the patients in the supine position and under complete aseptic conditions, inguinal canal block and intraincisional infiltration were performed. Atraumatic 22-G Whitacre blunt needle was used. Initially, the anterior superior iliac spine was palpated, and a mark was made 2 cm medial and 2 cm superior from it. After skin preparation and infiltration with a local anesthetic, the needle was inserted perpendicular to the skin. Using the loss-of-resistance technique, spaces between the external, the internal obliques, and the transversus abdominis muscles were identified, and 2 ml of the study drug was injected. The needle was withdrawn to the skin, and the procedure was repeated at a 45° angle in both the medial and the lateral directions in the same way; thus, a total of 20 ml saline (contain 1 mg/kg tramadol) was placed in a fan-like distribution between the external and the internal oblique as well as between the internal oblique and the transversus abdominis muscles. At the end of the surgery, neuromuscular blockade was reversed with neostigmine 0.04 mg/kg and 0.01 mg/kg atropine. The laryngeal mask was removed, and then the patients were transferred to the recovery room and monitored for 2 h, till full recovery and pain assessment. A standard postoperative analgesia regimen was prescribed as paracetamol 1 g/6 h intravenous infusion and meperidine 25 mg intravenously if the VAS was 3 or more or when the patient suffered from pain between the assessment intervals in all groups.
Sample size calculation
- The duration of the surgery [the time from skin incision to wound closure (min)].
- The total intraoperative fentanyl requirement (μg).
- The total intraoperative blood loss from the surgical gauze and the suctioned amount, if any.
- Postoperative hemodynamic parameters, HR and MAP, were recorded at 2, 6, 12, and 24 h postoperatively.
- The postoperative pain severity was assessed using the VAS (where 0 = no pain and 10 = worst pain) at 2, 6, 12, and 24 h postoperatively.
- Postoperative sedation was assessed at the same time interval as VAS using a four-point scale (1 = fully awake; 2 = somnolent, responds to verbal stimuli; 3 = somnolent, responds to tactile stimuli; and 4 = somnolent, responds to painful stimuli)  .
- Postoperative nausea and vomiting (PONV) were measured using a categorical scoring system (none = 0, present = 1).
- The time between the end of the surgery and the first analgesic requirement was compared.
- The total postoperative meperidine consumption during the first 24 h postoperatively was calculated.
- Surgeon satisfaction from this technique was assessed using the following scale: excellent, very good, good, or poor.
- At the end of 24 h, patients were asked about their overall opinion about the quality of pain relief using the following scale: excellent, very good, good, or poor.
Power analysis was performed using one-way analysis of variance on postoperative pain assessment by the VAS because it was the main outcome variable in the present study. Previous studies showed that the SD of postoperative pain assessment by VAS after 6 h was 0.6 in the tramadol group, with a mean of 2.5, one in the control group with a mean of 2.7, and one in the bupivacaine group with a mean of 3  . At a power of 0.6 and a-error of 0.05, a minimum sample size of 57 patients was calculated for the three groups. A total of 20 patients were included in each group to compensate for possible dropouts.
Data were summarized and analyzed; the results were reported as mean, SD, range (median), or n (%). Comparisons among numerical variables of the three groups were performed by an unpaired Student's t-test for parametric data or the Kruskal-Wallis test for nonparametric data. P values less than 0.05 were considered statistically significant and P values less than 0.001 were considered statistically highly significant. All statistical calculations are performed using computer programs Microsoft Excel version 7 (Microsoft Corporation, New York, USA).
| Results|| |
There were no statistically significant differences among the three studied groups regarding the patients' age, BMI, and the duration of surgery. The mean intraoperative fentanyl requirement was highly significantly lower (P < 0.001) in both the bupivacaine and the tramadol groups compared with the control group, with the values 60 ± 20, 57 ± 18, and 120 ± 29, respectively. There were no statistically significant differences between the tramadol group and the bupivacaine group regarding fentanyl requirements ([Table 1]).
The postoperative MAP was highly significantly lower (P < 0.001) in both the bupivacaine and the tramadol groups compared with the control group, with the values 99 ± 4, 97 ± 3, and 119 ± 1, respectively, 2 h postoperatively. The MAP (mmHg) was significantly lower (P < 0.05) in the tramadol group compared with the control and the bupivacaine groups, with the values 97 ± 3, 106 ± 7, and 103 ± 6, respectively, 6 h postoperatively. There were no statistically significant differences among the three studied groups at 12 h postoperatively ([Table 2]).
The postoperative HR was significantly lower (P < 0.05) in both the bupivacaine and the tramadol groups compared with the control group, with the values 88 ± 4, 87 ± 5, and 97 ± 11, respectively, 2 h postoperatively. The mean postoperative HR (bpm) was significantly lower (P < 0.05) in the tramadol group compared with the control and the bupivacaine groups, with the values 87 ± 5, 96 ± 11, and 92 ± 5, respectively, at 6 h postoperatively. There were no statistically significant differences among the three studied groups at 12 h postoperatively ([Table 3]).
The postoperative VAS was highly significantly lower (P < 0.001) in both the bupivacaine and the tramadol groups compared with the control group, with the values [median (range)] [2 (1-5)], [2 (2-5)], and [5 (2-6)], respectively, at 2 h postoperatively. The postoperative VAS was highly significant lower (P < 0.001) in the tramadol group compared with the control and the bupivacaine groups, with the values [2 (1-4)], [4 (2-6)], and [4 (1-5)], respectively, at 6 h postoperatively. There were no statistically significant differences among the three studied groups at 12 or 24 h postoperatively ([Table 4]).
The postoperative sedation score 2 h postoperatively was significantly higher (P < 0.05) in the bupivacaine and the tramadol groups compared with control groups, and the values [median (range)] were [2 (1-2)], [2 (1-3)], and [1 (1-2)], respectively; meanwhile, it showed significantly lower values in the bupivacaine group compared with the tramadol group. At 6 h postoperatively, the sedation score was significantly lower (P < 0.05) in the bupivacaine group compared with the control and the tramadol groups, with the values [2 (1-2)], [2 (1-3)], and [2 (1-3)], respectively. At 12 h postoperatively, the postoperative sedation score was significantly higher (P < 0.05) in the control group compared with the bupivacaine and the tramadol groups, with the values [2 (1-3)], [1 (1-2)], and [1 (1-2)], respectively ([Table 5]).
The time for the first postoperative analgesic request was highly significantly lower (P < 0.001) in the control group compared with the bupivacaine and the tramadol groups, with the values 31 ± 10, 116 ± 25, and 150 ± 30 min, respectively. Also, the time for the first postoperative analgesic request was highly significantly lower (P < 0.001) in the bupivacaine group compared with the tramadol group, with the values 116 ± 25 and 150 ± 30 min, respectively ([Table 6]).
|Table 6 Time for the fi rst postoperative analgesic request and the total meperidine consumption during the fi rst 2 h postoperatively|
Click here to view
The total dose of postoperative meperidine consumption (mg) was highly significantly lower (P < 0.001) in both the bupivacaine and the tramadol groups compared with the control group, with the values 61 ± 17, 27 ± 7, and 100 ± 19, respectively. Again, the total dose of postoperative meperidine consumption was highly significantly lower (P < 0.001) in the tramadol group compared with the bupivacaine group, with the values 27 ± 7 and 61 ± 17, respectively ([Table 6]).
PONV at 2 h postoperatively was statistically highly significantly higher (P < 0.001) in the tramadol group compared with the control and the bupivacaine groups, with 17/20, 8/20, and 6/20 patients, respectively. Six hours postoperatively the PONV was highly significantly lower (P < 0.001) in the bupivacaine group compared with the control and the tramadol groups, with 4/20, 10/20, and 13/20 patients, respectively. There were no statistically significant differences among the three groups regarding the PONV when assessed 12 and 24 h, postoperatively ([Table 7]).
The scoring of intraoperative surgeon satisfaction was highly significantly lower (P < 0.001) in the control group compared with the tramadol group and the bupivacaine group, with the values [median (range)] [2 (1-2)], [4 (2-4)], and [3 (1-4)], respectively. However, the scoring of the intraoperative surgeon satisfaction was significantly higher (P < 0.05) in the tramadol group compared with the bupivacaine group, with the values [median (range)] [4 (2-4)] and [3 (1-4)], respectively ([Table 8]).
|Table 8 Scoring of intraoperative surgeon satisfaction and postoperative patient satisfaction|
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The scoring of postoperative patient satisfaction was highly significantly lower (P < 0.001) in the control group compared with the tramadol and the bupivacaine groups, with the values [median (range)] [1 (1-3)], [4 (2-4)], and [3 (1-4)], respectively. However, the scoring of the postoperative patient satisfaction was significantly higher (P < 0.05) in the tramadol group compared with the bupivacaine group, with the values [median (range)] [4 (2-4)] and [3 (1-4)], respectively ([Table 8]).
| Discussion|| |
The present, prospective randomized double-blinded study was performed to compare the effect of pre-emptive inguinal canal block in combination with intraincisional injection of either tramadol (1 mg/kg) or bupivacaine (0.25%) on postoperative pain relief, intraoperative fentanyl requirements, total 24-h postoperative meperidine requirements, and patient and surgeon satisfaction after elective inguinal hernioplasty. Regional anesthesia for inguinal hernia repair has gained a greater interest over time. Using additional regional anesthesia decreases general anesthetic requirements as well as the use of postoperative analgesia, thus aiding in early recovery and discharge  . Pain control in patients with hernia repair is an important issue. Inadequate pain relief may be problematic. Tramadol acts on the central monoaminergic systems, and this might be its mechanism of analgesia  . The findings of the current study were supported by the findings of a study conducted by Altunkaya et al.  , who proved that tramadol has local anesthetic effects and that rescue analgesic requirement was minimal with tramadol use. Gerηek et al.  in his study showed that subcutaneous tramadol infiltration provided effective analgesia and had anti-inflammatory effects. The results of the present study are also in accordance with a study conducted by Pozos-Guillιn Ade et al.  who showed that the administration of systemic and local tramadol (50 mg) reduced the pain scores compared with the control group (P < 0.05) in patients experiencing pain after removal of an impacted molar under local anesthesia. Results of the present study best correlate with the findings of Qayoom Lone et al.  ; in their study, local infiltration with tramadol was used in children undergoing inguinal herniotomy and orchidopexy, and it was found that patients had a longer postoperative analgesia time with lesser need for analgesics. In the study conducted by Jou et al.  , it was suggested that the mechanism of the sensory blocking action of tramadol occurred by blocking the voltage-dependent Na channel in a mechanism similar to local anesthetics. Kaki and Al Marakbi  , proved that local tramadol before herniorrhaphy wound closure gives better analgesia compared with bupivacaine in adults. In the study conducted by Sύvacύ et al .  , it was found that wound infiltration with 200 mg tramadol provided a longer pain-free time and less analgesic requirements in this group of patients undergoing tension-free inguinal hernia repair under spinal anesthesia as compared with the control group, and this result is similar to our results in proving the local effect of tramadol. Jabalameli et al.  , conducted a study on 120 patients undergoing cesarean sections under regional anesthesia, and they found that subcutaneous tramadol administration postoperatively was associated with a longer analgesia and morphine sparing as compared with the control group. The study conducted by Hopkins and colleagues demonstrated that more PONV were recorded from tramadol as compared with morphine. Moderate hemodynamic changes were recorded in both groups. Mild sedation was seen postoperatively in both groups  . Atunkaya and colleagues compared 60 patients undergoing excision of skin lesions under local anesthesia, who were randomly allocated into two groups: the tramadol and the prilocaine groups. The study proved that the local anesthetic effect provided by intradermal tramadol 5% is similar to that of prilocaine, but with higher local adverse effects  . Our results resemble the results of the study of Behdad and colleagues, wherein a comparison of 60 women undergoing cesarean sections was performed. Wound infiltration with either 50 mg tramadol or 10 ml bupivacaine 0.5% before skin closure was performed. The postoperative VAS and the time to the first postoperative analgesic were compared. The VAS was higher in the bupivacaine group compared with the tramadol group 6 h postoperatively. A nonsignificant difference in the postoperative consumption of analgesic was detected between the two groups  . The results of the present study are in line with the findings of Khajavi and colleagues, who compared 60 patients (age 18-60 years), ASA I-II, who were undergoing pyelolithotomy. They were randomly assigned to receive intravenous or subcutaneous wound infiltration with tramadol. The Ramsay sedation score was lower in the subcutaneous group (P < 0.001). The intravenous tramadol group showed a significantly higher pain severity. The average time for the first meperidine requirement was more in the subcutaneous group. The total meperidine consumption was lower in patients who had received subcutaneous wound infiltration with tramadol compared with those who had received intravenous tramadol (P < 0.001). More frequent nausea and vomiting occurred during the first postoperative hour, however, with lower incidence in the subcutaneous group  . In contrast to our results, when tramadol 100 mg was added to lidocaine 0.5% in the bier block in the study conducted by Langlois et al.  , there was no additive effect in the intraoperative tourniquet pain reduction as compared with lidocaine alone and it was also not effective in decreasing postoperative pain.
| Conclusion|| |
Pre-emptive inguinal canal block and intraincisional infiltration using tramadol 1 mg/kg provided better intraoperative and postoperative pain control. The amount of fentanyl required intraoperatively was decreased, the time to first analgesic requirement was prolonged, the total analgesic consumption during the first postoperative 24 h was reduced, and hence, their side effects were reduced, thus facilitating early ambulation and discharge. Patient and surgeon satisfaction were higher when compared with the bupivacaine and the control groups. Further studies, probably with a larger sample size, are recommended to ensure the efficacy of the local anesthetic effect of tramadol.
| Acknowledgements|| |
Conflicts of interest
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8]