European Journal of Cardiovascular Medicine

Combined spinal–epidural (CSE) anaesthesia combines the advantages of spinal and epidural techniques, offering rapid onset of dense sensory and motor block with the flexibility of prolonged analgesia through the epidural catheter. It is extensively used in orthopaedic, gynaecological, and general surgical procedures in Indian clinical practice. Despite its advantages, neuraxial anaesthesia is frequently associated with haemodynamic instability, particularly hypotension, due to sympathetic blockade leading to decreased systemic vascular resistance and venous pooling.^1-2 The degree of hypotension depends on several factors including patient age, volume status, dose and baricity of local anaesthetic, and patient positioning. Patient position during administration of spinal anaesthesia influences the spread of intrathecal local anaesthetic and the extent of sympathetic block. While the sitting position is commonly preferred for ease of identification of landmarks, the lateral decubitus position may result in a more gradual onset of block and improved haemodynamic stability.³  This study aims to evaluate the impact of patient positioning on haemodynamic parameters during CSE anaesthesia in the Indian population. Previous studies have demonstrated that patient positioning plays an important role in determining the spread of spinal anaesthesia. Sitting position has been associated with higher sensory block levels and increased incidence of hypotension, especially with hyperbaric local anaesthetics.⁴ Lateral positioning has been reported to provide a more controlled spread and reduced sympathetic blockade. Indian studies on CSE anaesthesia have highlighted hypotension as the most common complication, necessitating vasopressor use and fluid boluses. However, limited prospective data are available comparing haemodynamic changes specifically related to patient positioning during CSE, prompting the need for this study.

Aims and Objectives

Primary Objective

• To compare haemodynamic changes in sitting versus lateral decubitus position during CSE anaesthesia

Secondary Objectives

• To assess the incidence of hypotension in both positions
• To compare vasopressor requirements
• To evaluate heart rate variations

Study Design

Prospective, randomized comparative study.

Study Setting

Department of Anaesthesiology, The Oxford Medical College, Hospital & Research Center, Bangalore, Karnataka, India.

Study Duration

Study was conducted over one year from January  2016 to December 2016.

Study Population

Sixty adult patients scheduled for elective lower abdominal or lower limb surgery under CSE anaesthesia.

Inclusion Criteria

• Age 18–60 years
• ASA physical status I and II
• Elective surgery under CSE anaesthesia

Exclusion Criteria

• Patient refusal
• Coagulopathy
• Infection at puncture site
• Severe cardiac disease
• Spine deformity

Grouping

• Group S (n = 30): CSE administered in sitting position
• Group L (n = 30): CSE administered in lateral decubitus position

Anaesthetic Technique

After standard monitoring (ECG, NIBP, SpO₂) and preloading with crystalloid solution, CSE was performed at the L3–L4 interspace using a standard technique. Following intrathecal drug administration, patients were positioned supine. Epidural catheter placement was confirmed and secured.

Parameters Recorded

• Heart rate (HR)
• Systolic blood pressure (SBP)
• Diastolic blood pressure (DBP)
• Mean arterial pressure (MAP)

Measurements were recorded at baseline and at 2, 5, 10, 15, 20, and 30 minutes following spinal anaesthesia.

• Hypotension: Decrease in systolic blood pressure >20% from baseline or SBP <90 mmHg
• Bradycardia: HR <50 beats per minute

Statistical Analysis

Data were analysed using appropriate statistical tests. Continuous variables were expressed as mean ± standard deviation. A p value <0.05 was considered statistically significant.

Table 1: Demographic Profile of Patients

Both groups were comparable with respect to age, gender, weight, and ASA physical status, with no statistically significant differences.

Interpretation:
Both groups were comparable with no statistically significant difference.

Table 2: Mean Systolic Blood Pressure (mmHg)

Observation:
Group S showed a greater fall in systolic blood pressure compared to Group L.

Table 3: Mean Arterial Pressure (MAP) (mmHg)

Inference:
MAP reduction was significantly greater in the sitting position group (p < 0.05).

Table 4: Heart Rate (beats/min)

Table 5: Incidence of Hypotension and Vasopressor Use

Haemodynamic Changes

Patients in the sitting position group showed a greater reduction in systolic blood pressure and mean arterial pressure compared to those in the lateral position. The maximum fall in blood pressure was observed within the first 10 minutes after spinal anaesthesia.

Incidence of Hypotension

• Group S: Higher incidence of hypotension
• Group L: Lower incidence and lesser severity

Vasopressor requirement was significantly higher in the sitting position group.

Heart Rate Changes

No significant difference in heart rate was observed between the two groups, although occasional bradycardia was noted in the sitting position group

This prospective study demonstrates that patient positioning during CSE anaesthesia has a significant impact on haemodynamic stability. The sitting position was associated with a higher incidence of hypotension, likely due to rapid and extensive sympathetic blockade resulting from cephalad spread of local anaesthetic after repositioning to supine.^5-6 The lateral decubitus position allows a more controlled spread of intrathecal local anaesthetic, resulting in gradual onset of sympathetic block and improved haemodynamic stability. These findings are consistent with previous Indian and international studies evaluating spinal anaesthesia.⁷In high-risk patients such as the elderly or those with limited cardiac reserve, lateral positioning during CSE may offer a safer alternative.⁸

Limitations of the Study

• Relatively small sample size
• Short-term haemodynamic assessment
• Single-centre study.

Patient positioning during combined spinal–epidural anaesthesia significantly affects haemodynamic parameters. Lateral decubitus positioning provides better haemodynamic stability compared to the sitting position. Careful selection of patient position can improve safety and outcomes during neuraxial anaesthesia.

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