Clonidine as an Adjuvant to Lignocaine Infiltration for Prolongation of Analgesia after Episiotomy.

BACKGROUND: Epidural labor analgesia has not been fully accepted despite many advantages. Many times, the pregnant females reach hospital without antenatal checkup, and at that time, "episiotomy infiltration" becomes an ideal method for vaginal delivery. One of the most important problems after episiotomy is the severe perineal pain on the 1st day of postpartum period.
OBJECTIVES: We compared the efficacy of clonidine 1 μg/kg as an adjuvant to 20 mg/ml lignocaine infiltration along the line of episiotomy incision for prolonging the duration and quality of analgesia with respect to various activities by single injection.
METHODOLOGY: Majority of the patients, 94.2% in our study, had no idea about labor analgesia, and only 2.5% of all the patients expressed their interest to deliver without suffering from labor pains. One hundred and twenty pregnant female patients scheduled for full-term vaginal delivery were assigned into lignocaine and lignocaine-clonidine group according to infiltration they received. Pain scoring using visual analog scale and maternal satisfaction scale was monitored. At the end of the research project, the data were compiled and analyzed using appropriate statistical tests.
RESULTS: Duration of analgesia after episiotomy during sitting, walking, and squatting was 22.7 ± 1.32, 21.73 ± 1.47, and 19.875 ± 1.48 h in clonidine + lignocaine group and 6.06 ± 1.26, 5.33 ± 1.18, and 4.01 ± 1.28 h in lignocaine only group, respectively, which was highly statistically significant P < 0001.
CONCLUSIONS: Clonidine when added to 2% lignocaine infiltration in episiotomy improves the quality and significantly enhances the duration of analgesia.

INTRODUCTION

Episiotomy is the surgical cut made through the perineum during labor to make the vagina larger with the intention of easing the birth of the child. It is the most frequent procedure in obstetrics and is commonly done using local anesthetic agents.[12] The degree of perineal discomfort is related to perineal trauma which is severe in the immediate postnatal period.[3] It interferes with basic daily activities and has impact on motherhood experiences.[4]

Lignocaine infiltration anesthesia has been the traditional mainstay worldwide before performing the episiotomy. After the birth of the baby, usually, nonsteroidal anti-inflammatory drugs (NSAIDs) are prescribed to the new mother for pain relief.

Strategies to reduce perineal trauma and the appropriate repair of any perineal damage sustained are important for avoiding and alleviating pain. Factors that may influence the severity of pain experienced include mode of birth,[5] degree of perineal trauma,[6] type of suture material, and perineal repair technique.[567] For relieving the episiotomy pain, both nonpharmacological and pharmacological methods are tested. Application of heat or cold and sitz baths are examples of nonpharmacological methods of pain relief that are often inadequate. Acetaminophen with codeine is frequently used, but adverse effects, such as constipation, nausea, stomach pain, and dizziness, limit its appeal.[8] Lignocaine infiltration anesthesia has been the traditional mainstay worldwide before performing the episiotomy, and after the birth of the baby, usually, NSAIDs are prescribed to the new mother for pain relief.[910]

Clonidine, α2 adrenergic receptor agonist, has been the focus of interest for its analgesic, sedative, sympatholytic, and anesthetic sparing effects and hemodynamic stabilizing properties. It augments the action of local anesthetics in regional blockades by interrupting the neural transmission of painful stimuli in A delta and C fibers and augments the blockade of local anesthetic agents by increasing the conductance of K+ ions in nerve fibers. It also exerts a vasoconstricting effect on smooth muscles, which results in decreased absorption of the local anesthetic drug and eventually prolongs the duration of analgesia.[111213]

Clonidine has been used in every route as far as an anesthesiologist is concerned be it epidurally,[14] intrathecally,[15] intravenously for obtundation of laryngoscopic response,[16] used in brachial blocks, in labor analgesia,[17] but in the perineal infiltration was still to be explored.[1819] There were randomized trials done by McCartney et al. and Murphy et al., who investigated the usefulness of clonidine when added to local anesthetics in peripheral blocks and infiltration and postulated that clonidine improved the duration of postoperative analgesia only when used as an adjuvant to intermediate-acting local anesthetics (lidocaine, mepivacaine, prilocaine) and that it was not worthwhile to combine it with long-acting local anesthetics (ropivacaine, bupivacaine, and levobupivacaine).[2021]

Keeping this profile in mind, we used clonidine in dose of 1 μg/kg as an adjuvant to 20 mg/ml lignocaine for infiltration along the line of episiotomy incision which would prolong the duration of pain relief and thereby decrease the requirement of NSAIDs by the mother and thus improve the quality of analgesia and comfort of mother by one single injection.

The aim of this study was to compare clonidine in dose of 1 μg/kg adjuvant to 20 mg/ml lignocaine infiltration in comparison to lignocaine alone for analgesia after episiotomy with respect to various activities such as sitting, walking, and squatting after delivery and the time when first rescue analgesic was required, the total dose of analgesics required after episiotomy, and maternal satisfaction scores.

METHODOLOGY

Approval from the Ethical Committee was attained. This study was a prospective randomized controlled trial of 120 female patients from age group 18 to 40 years belonging to the American Society of Anesthesiologists (ASA) Class I and II, scheduled for full-term vaginal delivery who were ready to complete pain and patient satisfaction assessments. A written informed consent was obtained from all the patients after explaining them the nature of the study.

Blinding was done using similar type of syringes, an additive medication clonidine 1 μg/kg/mg or placebo which was loaded by person who was not giving the episiotomy, and computer-generated numbers were used for the selection of them. Obstetrician conducting the delivery was same for all the patients. Analgesia was observed by observer who did know about the drug given. Patients belonging to ASA class III and IV, on anti platelet drugs, with coagulopathies, severe PIH, severe infection at episiotomy site and who are seropositive and lignocaine sensitive were excluded from the study.

Patients were assigned into two groups of sixty each, lignocaine group (L) and lignocaine + clonidine group (C + L). Group L received 7 ml of 20 mg/ml lignocaine while Group C + L received 7 ml of 20 mg/ml lignocaine with clonidine in dose of 1 μg/kg bodyweight. Postinfiltration, episiotomy was done and delivery patients were monitored for pulse, blood pressure, pain score assessments using visual analog scale (VAS), the time when first rescue analgesic with oral diclofenac sodium 50 mg was given, and total number of analgesics given. Pain scoring was done with respect to various activities such as sitting, walking, and squatting position.

Maternal satisfaction was assessed by asking the females to rate her analgesia on a scale of 10 numbers and whether they will prefer to have similar analgesia in subsequent deliveries.[22]

Excellent (9, 10)

Satisfactory (6, 7, 8)

Fair (3, 4, 5)

Poor (1, 2).

A VAS was used as quantitative measurement for assessment of pain.[91022232425]

Statistical analysis

At the end of the study, all data were compiled and analyzed statistically using diagrammatic representation. Descriptive data presented as mean ± standard deviation, and continuous data were analyzed by paired/unpaired t-tests. Chi-square test was used to assess the statistical difference between the two groups.

RESULTS

There were no statistical differences between the clonidine and lignocaine group and lignocaine alone group for demographic variables (age, weight, ASA health status classes, episiotomy length, and gestational age) [Table 1].

Table 1

Demographic data

All the vitals such as pulse and blood pressure monitored were similar in both the groups with no hypotension and bradycardia in any of the patients.

Majority of the patients, 94.2% in our study, had no idea about labor analgesia and only 2.5% of all the patients expressed their interest to deliver without suffering from labor pains. Only 5% patients from Group C + L and 6.66% from Group L were aware of what labor analgesia is. However, when asked if they were given chance to deliver vaginally without suffering from labor pains, only 3.33% from Group C + L and 1.67% from Group L gave consent for it [Table 2]; this could be correlated with the level of education and socioeconomic status, fear of delivery complications without labor pains.

Table 2

Questionnaire

Majority of the patients were primigravida (71.6% in Group C + L, 75% in Group L) but 28.3% in Group C + L and 25% in Group L were secundigravida. They needed episiotomy for vaginal delivery as shown in Table 3 (P > 0.05).

Table 3

Parity

The duration of analgesia with respect to various activities was significantly increased in Group C + L when compared to lignocaine. The analgesia during sitting was for 22.7 ± 1.32 h in Group C + L and 6.06 ± 1.26 h in Group L. The analgesia during walking was for 21.73 ± 1.47 h in Group C + L and 5.33 ± 1.18 h in Group L and the analgesia during squatting was for 19.875 ± 1.48 h and 4.01 ± 1.28 h in Group C + L and Group L, respectively, which was statistically significant P < 0.0001 depicted in Table 4 and Figure 1.

Table 4

Duration of analgesia

Figure 1

Duration of analgesia

First dose of analgesia was given at 22.7 ± 1.3 h and 6.066 ± 1.26 h in Group C + L and Group L, respectively, which was highly significant (P < 0.0001). Almost two doses of analgesia were given in Group L on 1st day as shown in Table 5 and Figure 2.

Table 5

Time of rescue analgesia

Figure 2

Time of first rescue analgesia

93.33% from Group C + L were completely satisfied from the analgesia they received from single injection and rated as excellent analgesia and wanted similar type of analgesia for next deliveries if offered, and 6.67% patients from Group C + L and 61.67% from Group L were satisfied to 60%–80% and rated analgesia as satisfactory. 38.33% from Group L were not at all satisfied from the analgesia offered to them and rated as fair or poor analgesia [Table 6].

Table 6

Maternal satisfaction scale

There were no side effects (nausea, hypotension, bradycardia, respiratory depression, dry mouth) noted in either of the group in the first 24 h in postnatal period.

DISCUSSION

Perception of pain is subjective and the use of analgesia is influenced by many factors in addition to the level of pain experienced. In the management of postepisiotomy pain, NSAIDs 3–4 times a day have been found to be effective but not without related illness from adverse effects gastritis to mother and sometimes to babies as studied by Lim et al.[23]

Pitangui et al. examined the effectiveness of high-frequency transcutaneous electrical nerve stimulation (TENS) on pain of primiparous puerperal who had experienced natural childbirth with an episiotomy and reported that high-frequency TENS treatment (100 Hz frequency and 75 μs pulse for 60 min) significantly reduced pain intensity of episiotomy.[24]

In the other study in 2012, Santos Jde et al. examined the low-level laser therapy for pain relief after episiotomy and surveyed 115 women with right mediolateral episiotomy and reported that low-level laser therapy cannot decrease perineal pain related to episiotomy.[25]

Our results were similar to the study of Singh et al. when compared to demographic variables (age, weight) and duration of analgesia related to various activities.[9] Duration of analgesia after episiotomy was significantly prolonged with respect to routine activities such as sitting, walking, and squatting.

Clonidine, an antihypertensive, is frequently used adjuvant to local anesthetics whose analgesic properties are attributable to its α2 agonist properties. The four proposed mechanisms for the action of clonidine in peripheral nerve blocks are centrally mediated analgesia, vasoconstriction due to α2 adrenoceptor effect, attenuation of inflammatory response, and direct action on peripheral nerve.[1] They proposed that clonidine, by enhancing activity-dependent hyperpolarization generated by the Na/K pump during repetitive stimulation, increases the threshold for initiating the action potential causing slowing or blockage of conduction.[9]

In our study, 28.3% in Group C + L and 25% in Group L were secundigravida and especially the secundigravidas could appreciate the difference in analgesia and maternal well-being when they compared with their earlier delivery.

CONCLUSIONS

Clonidine when added to 2% lignocaine infiltration in episiotomy improves the quality and enhances the duration of sensory analgesia [Table 7], thus eliminating the use of oral analgesics and their unwanted side effects and making the delivery more comfortable with routine activities. Majority of the mothers who were highly satisfied with the analgesia requested to enroll themselves for their future delivery with the similar drug (clonidine with lignocaine).

Table 7

Evaluation report

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.