Background: Continuous spinal anesthesia (CSA) and combined spinal epidural anesthesia (CSE) are safe and reliable anesthesia methods in knee arthroplasties.
Objectives: This study aimed at comparing the efficacy and hemodynamic changes of CSA technique versus single interspace CSE technique in knee arthroplasties intra & postoperatively, and the potential adverse effects for both techniques.
Patients and Methods: After approval of Institutional ethical committee and obtaining written informed consents, forty patients aged 18 to 55 years of both sexes and American Society of Anesthesiologists (ASA) class I, II, were scheduled for elective knee arthroplasties. All Patients were assigned randomly by using a computerized program to one of the two equal groups:
Group CSA: Patients undergoing elective knee arthroplasty received continuous spinal anesthesia.
Group CSE: Patients undergoing elective knee arthroplasty received single interspace combined spinal epidural anesthesia.
The following parameters were assessed:
Hemodynamics: including heart rate and systolic (SBP) and diastolic arterial blood pressures (DBP), and percentage of oxygen saturation (SpO2) were obtained then recorded at 5^th, 15^th, 30 minutes, and at 1^st, 2^nd, 4^th hours intra-operatively till the end of surgery. Postoperatively, they were obtained at 0, 1 hour and every four hours for first 24 hours.
Anesthetic complications: PDPH, urine retention, and Postoperative nausea and vomiting (PONV). Postoperative pain was evaluated at rest using a 10-cm Visual analogue scale (VAS) (0 cm=no pain; 10 cm=worst pain possible) and pain scores were recorded at 30 min and 1^st, 2^nd, 4^th, 6^th, 12^th and 24^th hours post-operatively. This prospective randomized clinical trial study was conducted at Al- Azhar University Hospitals (Al- Hussein and Bab-Al-Shaarya) at the orthopedics operating theatre from March 2019 till September 2019.
Results: No significant difference between the two groups regarding the length of surgery, hypoxia, post-operative nausea and vomiting (PONV), post-operative pain score. The application time of the anesthetic technique was significantly shorter in the CSA group than CSE group. The heart rate was significantly higher in the CSE group at 1^st minutes while SBP and DBP were significantly lower in the CSE group at 1^st minutes than the CSA group. Post dural puncture headache (PDPH), and urine retention was significantly higher in the CSA group than the CSE group. PDPH occurred in 35% of the CSA group compared to 10 %. Urine retention occurred in 25% of the CSA group compared to 5% of the CSE group. The total dose of bupivacaine (0.5%) collectively given intra-operatively and morphine postoperatively were significantly lower in the CSA group than the CSE group.
Conclusion: The study revealed that CSA and CSE were both effective and safe techniques for knee arthroplasties with superiority of CSA in hemodynamic stability intraoperative at 1^st minutes of surgery. CSA offered many advantages over epidural anesthesia by using smaller anesthetic dose with rapid onset and recovery of motor and sensory blockade with better cardiovascular stability than CSE.