This study is a prospective, randomized, double-blind clinical trial. Its aim is to evaluate whether adding a pericapsular nerve group (PENG) block to spinal anesthesia can reduce the inflammatory response after hip surgery in children. Hip surgery in children can cause a strong stress and inflammatory reaction, which may affect pain after surgery, the need for opioid medications, and recovery. Children aged 3 to 8 years will be randomly assigned to one of two groups: spinal anesthesia alone or spinal anesthesia combined with a PENG block. The main goal is to compare changes in the Systemic Immune-Inflammation Index (SII), a blood-based marker of inflammation, measured before surgery and 24 hours after surgery. Additional outcomes include other inflammatory markers, postoperative pain, opioid use, time to first rescue pain medication, and side effects.
Hip surgery in children is associated with a significant inflammatory and physiological stress response, which may contribute to postoperative pain, increased opioid requirements, and delayed recovery. Composite inflammatory indices derived from routine blood tests are increasingly used as accessible markers of systemic inflammation. The Systemic Immune-Inflammation Index (SII), calculated as platelet count × neutrophil count / lymphocyte count, reflects the balance between inflammatory and immune responses and has been proposed as a sensitive indicator of surgical stress. The pericapsular nerve group (PENG) block is a regional anesthesia technique used in hip surgery that provides effective analgesia with minimal motor impairment. Its potential effect on systemic inflammatory response remains insufficiently characterized. The study is designed as a prospective, randomized, double-blind, single-center controlled trial with two parallel groups. Pediatric patients undergoing elective hip surgery will be allocated in a 1:1 ratio to receive spinal anesthesia alone or spinal anesthesia combined with ultrasound-guided PENG block. A sham procedure will be performed in the control group to maintain blinding. Standardized perioperative management and postoperative analgesia will be applied in all participants. The primary endpoint is the change in SII between the preoperative baseline and 24 hours after surgery. Secondary endpoints include additional inflammatory indices, C-reactive protein levels, postoperative pain intensity, opioid consumption, time to first rescue analgesia, and incidence of adverse events. Blood samples will be collected at predefined time points for the assessment of inflammatory markers.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
DOUBLE
Enrollment
100
Ultrasound-guided regional anesthesia technique targeting the articular branches of the hip joint to provide postoperative analgesia.
Simulated procedure performed to maintain blinding without administration of local anesthetic.
Poznan University of Medical Sciences
Poznan, Poland
Systemic Inflammation Response Index (SIRI)
Systemic Inflammation Response Index (SIRI) is used as a composite marker of systemic inflammatory activation. It is calculated from peripheral venous blood samples using the formula: SIRI = (Neutrophil count × Monocyte count) / Lymphocyte count All parameters are obtained from routine complete blood count (CBC) analysis and expressed in ×10⁹/L. SIRI reflects the interaction between innate immune activation (neutrophils and monocytes) and adaptive immune suppression (lymphocytes). Higher SIRI values indicate greater systemic inflammatory response.
Time frame: 12 hours after surgery
Systemic Inflammation Response Index (SIRI)
Systemic Inflammation Response Index (SIRI) is used as a composite marker of systemic inflammatory activation. It is calculated from peripheral venous blood samples using the formula: SIRI = (Neutrophil count × Monocyte count) / Lymphocyte count All parameters are obtained from routine complete blood count (CBC) analysis and expressed in ×10⁹/L. SIRI reflects the interaction between innate immune activation (neutrophils and monocytes) and adaptive immune suppression (lymphocytes). Higher SIRI values indicate greater systemic inflammatory response.
Time frame: 24 hours after surgery
Systemic Inflammation Response Index (SIRI)
Systemic Inflammation Response Index (SIRI) is used as a composite marker of systemic inflammatory activation. It is calculated from peripheral venous blood samples using the formula: SIRI = (Neutrophil count × Monocyte count) / Lymphocyte count All parameters are obtained from routine complete blood count (CBC) analysis and expressed in ×10⁹/L. SIRI reflects the interaction between innate immune activation (neutrophils and monocytes) and adaptive immune suppression (lymphocytes). Higher SIRI values indicate greater systemic inflammatory response.
Time frame: 48 hours after surgery
Aggregate Index of Systemic Inflammation (AISI)
Aggregate Index of Systemic Inflammation (AISI) is calculated as: AISI = (Neutrophil count × Monocyte count × Platelet count) / Lymphocyte count All values are obtained from routine CBC and expressed in ×10⁹/L. AISI integrates neutrophils, monocytes, platelets, and lymphocytes, providing a broader assessment of systemic inflammatory and immune response compared to single ratios.
Time frame: 12 hours after surgery
Aggregate Index of Systemic Inflammation (AISI)
Aggregate Index of Systemic Inflammation (AISI) is calculated as: AISI = (Neutrophil count × Monocyte count × Platelet count) / Lymphocyte count All values are obtained from routine CBC and expressed in ×10⁹/L. AISI integrates neutrophils, monocytes, platelets, and lymphocytes, providing a broader assessment of systemic inflammatory and immune response compared to single ratios.
Time frame: 24 hours after surgery
Aggregate Index of Systemic Inflammation (AISI)
Aggregate Index of Systemic Inflammation (AISI) is calculated as: AISI = (Neutrophil count × Monocyte count × Platelet count) / Lymphocyte count All values are obtained from routine CBC and expressed in ×10⁹/L. AISI integrates neutrophils, monocytes, platelets, and lymphocytes, providing a broader assessment of systemic inflammatory and immune response compared to single ratios.
Time frame: 48 hours after surgery
Platelet Mass Index (PMI)
Platelet Mass Index (PMI) reflects total circulating platelet mass and is calculated as: PMI = Platelet count × Mean Platelet Volume (MPV) Platelet count is expressed in ×10⁹/L and MPV in femtoliters (fL). PMI reflects platelet activation and thrombo-inflammatory potential, which may increase in response to surgical stress.
Time frame: 12 hours after surgery
Platelet Mass Index (PMI)
Platelet Mass Index (PMI) reflects total circulating platelet mass and is calculated as: PMI = Platelet count × Mean Platelet Volume (MPV) Platelet count is expressed in ×10⁹/L and MPV in femtoliters (fL). PMI reflects platelet activation and thrombo-inflammatory potential, which may increase in response to surgical stress.
Time frame: 24 hours after surgery
Platelet Mass Index (PMI)
Platelet Mass Index (PMI) reflects total circulating platelet mass and is calculated as: PMI = Platelet count × Mean Platelet Volume (MPV) Platelet count is expressed in ×10⁹/L and MPV in femtoliters (fL). PMI reflects platelet activation and thrombo-inflammatory potential, which may increase in response to surgical stress.
Time frame: 48 hours after surgery
C-reactive Protein (CRP) Concentration
C-reactive protein (CRP) is a laboratory marker of acute systemic inflammation measured in peripheral venous blood samples. CRP concentration is expressed in mg/L and determined using standard hospital laboratory methods. Higher CRP values indicate greater postoperative inflammatory response.
Time frame: 12 hours after surgery
C-reactive Protein (CRP) Concentration
C-reactive protein (CRP) is a laboratory marker of acute systemic inflammation measured in peripheral venous blood samples. CRP concentration is expressed in mg/L and determined using standard hospital laboratory methods. Higher CRP values indicate greater postoperative inflammatory response.
Time frame: 24 hours after surgery
C-reactive Protein (CRP) Concentration
C-reactive protein (CRP) is a laboratory marker of acute systemic inflammation measured in peripheral venous blood samples. CRP concentration is expressed in mg/L and determined using standard hospital laboratory methods. Higher CRP values indicate greater postoperative inflammatory response.
Time frame: 48 hours after surgery
Postoperative Pain Intensity
Postoperative pain intensity will be assessed using the FLACC scale (Face, Legs, Activity, Cry, Consolability), a validated observational pain scale for children, ranging from 0 to 10, where higher scores indicate greater pain intensity. Pain scores will be recorded at rest.
Time frame: 4 hours after surgery
Postoperative Pain Intensity
Postoperative pain intensity will be assessed using the FLACC scale (Face, Legs, Activity, Cry, Consolability), a validated observational pain scale for children, ranging from 0 to 10, where higher scores indicate greater pain intensity. Pain scores will be recorded at rest.
Time frame: 8 hours after surgery
Postoperative Pain Intensity
Postoperative pain intensity will be assessed using the FLACC scale (Face, Legs, Activity, Cry, Consolability), a validated observational pain scale for children, ranging from 0 to 10, where higher scores indicate greater pain intensity. Pain scores will be recorded at rest.
Time frame: 12 hours after surgery
Postoperative Pain Intensity
Postoperative pain intensity will be assessed using the FLACC scale (Face, Legs, Activity, Cry, Consolability), a validated observational pain scale for children, ranging from 0 to 10, where higher scores indicate greater pain intensity. Pain scores will be recorded at rest.
Time frame: 24 hours after surgery
Postoperative Pain Intensity
Postoperative pain intensity will be assessed using the FLACC scale (Face, Legs, Activity, Cry, Consolability), a validated observational pain scale for children, ranging from 0 to 10, where higher scores indicate greater pain intensity. Pain scores will be recorded at rest.
Time frame: 48 hours after surgery
Opioid Consumption
Total opioid consumption within the first 48 hours after surgery will be recorded. All administered opioids will be converted to intravenous morphine milligram equivalents (MME) for standardization. Higher cumulative MME indicates greater analgesic requirement.
Time frame: 48 hours after surgery
Time to First Rescue Analgesia
Time from completion of surgery to first administration of rescue opioid analgesia. Measured in minutes. Shorter time indicates earlier breakthrough pain.
Time frame: 48 hours after surgery
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