Hemodynamic and Arterial Blood Gas Changes following Tourniquet Use under General Anesthesia with Sevoflurane or Propofol for Total Knee Replacement (TKR) in Geriatric Patients

BACKGROUND: Tourniquets are widely used to provide a clean surgical field but can induce variable hemodynamic and metabolic changes. Sevoflurane is one of anesthetic agents used for unstable or elderly patients, and propofol can be used for smooth induction and early recovery with few side effects. This study evaluated the differences in the hemodynamic and metabolic changes after the application of a tourniquet under general anesthesia with sevoflurane or propofol for total knee replacement (TKR). METHODS: Thirty elderly female patients scheduled to undergo TKR were allocated into two groups, the general anesthesia with sevoflurane group (S group, n = 15) or the propofol group (P group, n = 15). The hemodynamic parameters such as the mean arterial pressure (MAP), heart rate (HR), central venous pressure (CVP), cardiac index (CI), stroke volume (SV), systemic vascular resistance (SVR), and arterial blood analysis were checked immediately before (control, T1), at 5 (T2), 30 (T3) and 60 minute (T4) after inflation, and at 5 (T5) and 30 minutes after (T6) deflation. RESULTS: Compared with T1, the MAP increased significantly at T2, T3, and T4 in both groups. The increase in the SVR after inflating the tourniquet and the decrease in the SVR after deflation were lower in the P group than in the S group. The metabolic changes after deflating the tourniquet were similar in both groups. CONCLUSIONS: Compared with sevoflurane, propofol did not significantly decrease the hemodynamic and metabolic changes after placing a tourniquet during TKR for elderly patients. therefore, both sevoflurane and propofol are acceptable anesthetics for TKR in geriatric patients.

The Effects of Intrathecal Midazolam Added to Bupivacaine Spinal Anesthesia / 대한마취과학회지

BACKGROUND: Intrathecal additives are often used to enhance spinal anesthesia. Midazolam has been reported to have a spinally mediated antinociceptive effect. The aim of this study was to evaluate the effect of midazolam in addition to hyperbaric bupivacaine in spinal anesthesia. METHODS: Sixty ASA 1 or 2 adult patients scheduled for lower extremity surgery under spinal anesthesia were studied. Patients were allocated randomly to one of four groups to receive 2.8 ml of one of either of the following intrathecal solutions: hyperbaric bupivacaine 12 mg and normal saline 0.4 ml (group 1; n = 15), hyperbaric bupivacaine 12 mg, midazolam 0.5 mg and normal saline 0.3 ml (group 2; n = 15), hyperbaric bupivacaine 12 mg, midazolam 1 mg, and normal saline 0.2 ml (group 3; n = 15), or hyperbaric bupivacaine 12 mg and midazolam 2 mg (group 4; n = 15). The level, onset, and duration of spinal anesthesia as well as hemodynamic changes and side effects were assessed. RESULTS: The duration of spinal anesthesia was increased in the midazolam addition groups. The duration of anesthesia was significantly increased in group 4 compared to the other 3 groups (P<0.05). The onset, blood pressure, heart rate, and levels of sedation were no different between the 4 groups. No neurological deficit or other significant adverse effects were recorded. CONCLUSIONS: The addition of intrathecal midazolam to hyperbaric bupivacaine significantly improve the duration of spinal anesthesia without significant adverse effects. Therefore, the use of intrathecal midazolam in a dose not exceeding 2 mg can be used as an effective additive for spinal anesthesia.

Central Vein Catheterization for Prematurity / 대한마취과학회지

BACKGROUND: The establishment of safe and functional intravenous lines is of fundamental importance in premature sick neonates. Due to technical difficulties and various potential complications, central venous catheterization(CVC) has become an important part of long term care for prematurity. In terms of safety, it is believed by some that the central vein catheter tip should not be in the right atrium to avoid fatal complications. However, catheter performance and durability can be improved by positioning the catheter tip within the right atrium. Here, we evaluated the effectiveness of intraatrial catheter tip positioning for prematurities, to resolve this controversy between patient safety and catheter performance. METHODS: Premature neonates in whom CVC had been attempted at a nursery and pediatric intensive care unit were enrolled in this study. We successfully performed eighteen CVCs in twenty patients from September 2003 to December 2004. CVC tips were in positioned within the right atrium, and central venous route, central venous catheter depth, duration of catheterization, and any complications during or after catheterization were evaluated. RESULTS: Eighteen CVC were successful among twenty attempted in premature neonates. Two attempts failed due to guidewire insertion failure. A left supraclavicular venous approach was selected for 16 patients and a right approach for two. For intraatrial tip positioning, distances from skin to catheter tip were adjusted to an average depth of 5 cm in 11 patients and 6 cm in three patients. Two arterial punctures were the only minor complications. Mean duration of catheterization was 19 days without any long term complicaions. CONCLUSIONS: To prematue long term CVC performance, left supraclavicular subclavian vein catheterization and intraatrial catheter tip positioning should be considered a first option in premature neonates.

Effects of Aprotinin during Off-Pump Coronary Artery Bypass Grafting in Patients on Hemostasis Taking Aspirin / 대한마취과학회지

BACKGROUND: Patients with ischemic heart disease are frequently maintained on a regimen of aspirin because of its ability to reduce variable thrombotic complications. However, aspirin has been recognized as a causative factor of increased perioperative bleeding. This study was aimed to determine whether aprotinin maintain its efficacy at reducing blood loss in patients on aspirin undergoing off-pump coronary artery bypass grafting (OPCAB). METHODS: In the prospective, double blind, randomized study, we investigated 30 patients on preoperative aspirin medication undergoing OPCAB surgery. Patients received aprotinin (1 x 106 KIU bolus for loading plus 0.5 x 106 KIU/hr, n = 15, the aprotinin group) or saline solution (n = 15, the control group). Operation time, total transfusion amount during operation, and plasma D-dimer levels immediately after the induction of anesthesia and immediately after operation were investigated and compared between and within groups where possible. RESULTS: Both group showed no comparable demographic and operation data such as operation time and number of grafts. The aprotinin group showed significantly less transfusion amount than the control group (packed RBC 352.7 +/- 89.2 ml vs 478.0 +/- 132.1 ml). Compared with that immediately after anesthetic induction value, postoperative D-dimer significantly increased in the control group but not in the aprotinin group. CONCLUSIONS: The above results suggest that aprotinin significantly reduces transfusion amount and probably inhibits fibrinolysis in patients with aspirin undergoing OPCAB.