PENG: pericapsular nerve group; CKD: chronic kidney disease; ACC: American College of Cardiology; AHA: American Heart Association; ERAS: Enhanced Recovery After Surgery; THA: total hip arthroplasty; TKA: total knee arthroplasty; COX-2: cyclooxygenase-2; TNS: transient neurological symptoms; FICB: fascia iliaca compartment block; CFNC: continuous femoral nerve catheter; NSAIDs: nonsteroidal anti-inflammatory drugs; CHF: chronic heart failure; COPD: chronic obstructive pulmonary disease; ASA: American Society of Anesthesiologists. Here, PTGS2 is linked to chronic obstructive pulmonary disease.