Caesarean section is one of the most commonly performed surgical procedures worldwide. Adequate postoperative pain management after Caesarean delivery is crucial because insufficient analgesia adversely affects maternal recovery, breastfeeding, early mobilisation, mother–infant bonding, & overall patient satisfaction[1]. Poorly controlled postoperative pain can also increase the risk of chronic pain & postpartum depression.

The mainstay of postoperative pain management after Caesarean section is still multimodal analgesia. Despite their effectiveness, opioids have a number of unfavorable side effects, including nausea, vomiting, drowsiness, respiratory depression, itching, & delayed mobilization [2]. As a result, regional anesthesia methods are becoming more & more significant in contemporary obstetric anesthesia.

By obstructing the thoracolumbar nerves situated between the internal oblique & transversus abdominis muscles, the Transversus Abdominis Plane (TAP) block, a frequently used regional anesthetic method, gives analgesia to the anterior abdominal wall [3]. Following lower abdominal procedures, such as Caesarean sections, TAP block successfully lowers the need for postoperative opioids. Its analgesic effects, however, might be short-lived [4].

A relatively recent fascial plane block that has demonstrated encouraging outcomes in terms of extended postoperative analgesia is the quadratus lumborum (QL) block. Both somatic & visceral analgesia may result from the local anesthetic spreading into the paravertebral space & thoracolumbar fascia. According to a number of studies, QL block provides longer-lasting analgesia & better pain alleviation than TAP block [5–6].

The goal of this study was to assess the effectiveness of TAP block along ultrasound-guided QL block in patients having elective Caesarean sections while under spinal anesthesia [7].

Aim & Objectives

Aim: To compare the analgesic efficacy of ultrasound-guided Quadratus Lumborum block & Transversus Abdominis Plane block after elective Caesarean section.

Objectives:

1. To compare postoperative VAS pain scores between the two groups.
2. To compare the duration of postoperative analgesia.

Study Setting: Department of Anaesthesiology at a Shyam Shah medical college and hospital.

Study Duration: 12 months.

Sample Size: A total of 100 patients were included in the study.

Institutional Ethics Committee approval was obtained prior to commencement of the study. Written informed consent was obtained from all participants.

Inclusion Criteria:

1. ASA physical status I & II
2. Age between 20–35 years
3. Elective Caesarean section under spinal anaesthesia
4. Singleton pregnancy
5. Patients willing to participate

Exclusion Criteria:

1. Patient refusal
2. Coagulation disorders
3. Infection at injection site
4. Allergy to local anaesthetics
5. BMI >35 kg/m²
6. Chronic opioid use
7. Severe systemic illness
8. Randomisation

Patients were randomly allocated into two groups using computer-generated random numbers.

Group Q (n=50): Received bilateral QL block

Group T (n=50): Received bilateral TAP block

Anaesthetic Technique

All patients received standard spinal anaesthesia along 2.0 mL of 0.5% hyperbaric bupivacaine at the L3–L4 interspace. Standard monitoring included ECG, pulse oximetry, & non-invasive blood pressure.

Following completion of surgery, ultrasound-guided blocks were administered.

QL Block Technique

With the patient in the lateral position, a low-frequency curvilinear ultrasound probe was placed in the flank region. The quadratus lumborum muscle was identified & a 22G needle was advanced using an in-plane approach. Twenty millilitres of 0.25% bupivacaine was injected on each side.

TAP Block Technique

The ultrasound probe was placed between the iliac crest & costal margin in the mid-axillary line. The fascial plane between internal oblique & transversus abdominis muscles was identified. Twenty millilitres of 0.25% bupivacaine was injected bilaterally.

Postoperative Assessment

Pain assessment was performed using the Visual Analogue Scale (VAS) from 0 to 10.

Assessments were recorded at:

2 hours

4 hours

6 hours

12 hours

24 hours

Rescue analgesia was administered along intravenous tramadol 50 mg when VAS ≥4.

Statistical Analysis

Data were analyzed using SPSS software version 25. Continuous variables were expressed as mean ± standard deviation. Student’s t-test & Chi-square test were used for comparison. A p-value <0.05 was considered statistically significant.

Table 1: Demographic Characteristics Parameter Group Q (n=50) Group T (n=50) p-value Age (years) 27.6 ± 3.4 28.1 ± 3.7 0.48 Weight (kg) 68.4 ± 5.6 69.2 ± 6.1 0.52 Height (cm) 158.6 ± 4.8 159.1 ± 5.2 0.63 Duration of surgery (min) 58.2 ± 8.4 60.1 ± 7.9 0.29 ASA I/II 32/18 30/20 0.67 Both groups were comparable regarding demographic characteristics & surgical duration. Table 2: Comparison of VAS Scores Time Interval Group Q Group T p-value 2 hours 1.8 ± 0.6 2.6 ± 0.8 <0.001 4 hours 2.1 ± 0.7 3.4 ± 0.9 <0.001 6 hours 2.4 ± 0.8 4.1 ± 1.0 <0.001 12 hours 3.0 ± 0.9 4.8 ± 1.2 <0.001 24 hours 3.2 ± 0.7 4.0 ± 0.9 <0.001 VAS scores were significantly lower in Group Q at all postoperative intervals. Table 3: Duration of Analgesia & Rescue Analgesic Requirement Parameter Group Q Group T p-value Duration of analgesia (hours) 14.8 ± 3.2 8.6 ± 2.5 <0.001 Time to first rescue analgesia (hours) 13.9 ± 2.8 7.9 ± 2.2 <0.001 Total tramadol consumption (mg/24 h) 78 ± 22 142 ± 30 <0.001 Group Q showed significantly prolonged analgesia & lower opioid consumption. Table 4: Maternal Satisfaction & Adverse Effects Parameter Group Q Group T p-value Maternal satisfaction score (1–5) 4.6 ± 0.5 3.8 ± 0.7 <0.001 Nausea/Vomiting 04 (8%) 10 (20%) 0.08 Sedation 02 (4%) 06 (12%) 0.14 Hypotension 03 (6%) 02 (4%) 0.64 Block-related complications 00 00 — Maternal satisfaction scores were significantly higher in Group Q.

Postoperative pain following Caesarean section has both somatic & visceral components. Effective pain control enhances early ambulation, breastfeeding, maternal bonding, & patient satisfaction. Regional anaesthesia techniques such as TAP & QL blocks have become important components of multimodal analgesia strategies[8].

When compared to TAP block, QL block showed better analgesic efficacy in the current study. At all time intervals, patients who had QL block had significantly lower postoperative VAS scores [9].

The distribution of local anesthetic into the thoracolumbar fascia & paravertebral region, resulting in larger sensory blocking, may account for the persistent analgesic effect seen along QL block. TAP block may not sufficiently address visceral discomfort because it primarily affects the somatic nerves that feed the anterior abdominal wall [10].

Our results are in line along those of Blanco et al., who found that QL block prolonged analgesia following Caesarean section. Similarly, Elsharkawy et al. found that QL block improved postoperative pain levels & decreased opioid consumption [11].

Group Q experienced analgesia for a substantially longer period of time (14.8 ± 3.2 hours) than Group T (8.6 ± 2.5 hours). There was a statistically significant difference (p<0.001). The greater effectiveness of QL block is further supported by Group Q's decreased need for rescue analgesics [12].

Group Q consumed substantially less tramadol overall over a 24-hour period. Because it lessens opioid-related adverse effects such nausea, vomiting, & drowsiness, reducing opioid use is clinically significant. Although the difference did not achieve statistical significance, Group T experienced higher postoperative nausea & vomiting in our study [13].

The QL group had considerably better maternal satisfaction levels. Patient comfort, breastfeeding, mobility, & psychological well-being all benefit from effective pain management.

Neither group experienced any significant difficulties. By enabling direct visualization of anatomical features & needle insertion, ultrasound guided enhances both blocks' precision & safety [14].

QL & TAP blocks in lower abdominal surgery have been compared in a number of studies. When it comes to the length & quality of analgesia, QL block is superior, according to most of the current data. TAP block is still simpler to execute & requires less technical know-how, nevertheless.

Our study's prospective randomized design, sufficient sample size, & standardized postoperative evaluation are its strong points. It is important to recognize some restrictions, though. The study only comprised elective Caesarean sections & was carried out at a single facility. Chronic pain evaluation & long-term results were not assessed. To determine the best medication concentrations & methods for QL block, more multicentric research along bigger sample sizes is needed [15].

Ultrasound-guided Quadratus Lumborum block provided superior postoperative analgesia compared to Transversus Abdominis Plane block after elective Caesarean section. QL block significantly prolonged the duration of analgesia, reduced opioid consumption, lowered pain scores, & improved maternal satisfaction without increasing complications.

QL block can therefore be considered an effective & safe component of multimodal analgesia for Caesarean section patients.

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