How Changing Lumbar Epidural Pressure Affects the Distribution of Local Anesthetics and the Level of Spinal Anesthesia / 대한마취과학회지

BACKGROUND: More than 20 factors including increased intra-abdominal pressure, as in term pregnancy or in patients with ascites, may alter spinal anesthetic block height unexpectedly. The object of this study was to observe the change of spinal anesthetic block height following the change of direct lumbar epidural pressure. METHODS: Forty orthopedic patients (ASA physical status I or II) scheduled for spinal anesthesia with bupivacaine utilizing a combined spinal epidural set were divided into two groups randomly; Group C (control, n = 20) and Group S (saline, n = 20) Group S was injected with 10 ml saline to increase epidural pressure via an epidural needle after subarachnoid injection of bupivacaine. The change of epidural pressure was observed in the saline group and then the level of sensory block 5, 10, and 15 minutes after bupivacaine injection was measured in both groups. Statistical analysis was done using the Student's t-test. RESULTS: There were significant changes in sensory block level between the two groups (P<0.05). The peak epidural pressure generated by epidural saline injection was 20-53 mmHg. CONCLUSIONS: Epidural pressure generated by epidural saline injection affects the sensory block level.

Comparison of Transesophageal Doppler Monitor vs. Pulmonary Artery Catheter in the Hemodynamic Indices of Major Burn Patients Undergoing an Extensive Escharectomy / 대한마취과학회지

BACKGROUND: In major burn patients, many invasive monitors including a pulmonary artery catheter (PAC) are often required to assess hemodynamic status. An esophageal Doppler monitor (EDM), as a noninvasive method of measuring hemodynamic parameters, may be a substitute for a PAC in this clinical circumstance. This study was conducted to evaluate the validity of Doppler derived hemodynamic indices in comparison to that of a PAC. METHODS: A total of 20 critically ill, severe burn patients, scheduled for an elective escharectomy and application of artificial dermis, were enrolled for the placement of a PAC and EDM. Simultaneous data was collected in regular intervals and the various parameters were compared between the two methods. RESULTS: A total of 158 pairs of data in 20 patients were gathered. Among all the parameters, cardiac output (CO) and stroke volume (SV) showed consistently 20% less in EDM. Correlation coefficients of heart rate (HR), CO, SV and systemic vascular resistance (SVR) were 0.97, 0.54, 0.62, and 0.68 respectively. Corrected flow time (FTc) had poor correlations with central venous pressure (CVP) and pulmonary capillary wedge pressure (PCWP). In the mean time, significant, but very weak correlations with FTc vs. CO and SV were demonstrated. CONCLUSIONS: EDM may be a substitute for a thermodilution (TD) PAC technique, it can be used with usefulness for hemodynamic and preload assessment in major burn patients.

Evaluation of Safety and Usability of Low Pressure Carbon Dioxide Insufflation in Endoscopic Thyroidectomy / 대한마취과학회지

BACKGROUND: Carbon dioxide insufflation during an endoscopic thyroidectomy may cause an adverse effects on blood gas and hemodynamic status. This study was conducted to evaluate the safety of low pressure carbon dioxide insufflation during an endoscopic thyroidectomy. METHODS: Patients in ASA physical status I or II, scheduled for an endoscopic thyroidectomy (n = 70) were gathered for the evaluation. During the operative procedure, minute ventilation at a tidal volume 10 ml/kg and respiratory rate 10/minute was maintained. End-tidal carbon dioxide tension, blood pressure and heart rate were measured and compared before and at 10, 20, 30, 60 and 90 minutes after CO2 insufflation. RESULTS: End tidal carbon dioxide tension significantly increased up to 30 minutes and plateaued thereafter. Mean blood pressure significantly increased up to 30 minutes but there was no change in heart rate after CO2 insufflation. Complications were not reported. CONCLUSIONS: We concluded that low pressure carbon dioxide insufflation during an endoscopic thyroidectomy was safe and useful.

Percutaneous Vertebroplasty in a Patient with an Osteolytic Spinal Metastatic Tumor: A case report / 대한마취과학회지

Percutaneous vertebroplasty was first introduced in 1984. It allows reduction in pain and strengthening of bone. Main indications for this procedure are an osteoporotic compression fracture, hemangioma or a malignant spine tumor. Metastases to the vertebrae are not rare and often painful. Radiation therapy results in delayed (10 14 days) pain relief and minimal bone strengthening. Surgical procedures require significant postoperative recovery and have associated morbidity and mortality. However, a percutaneous vertebroplasty in patients with an osteolytic spinal metastatic tumor results in quick (1 3 days) disappearance of pain, vertebral consolidation, and spinal stability. We encontered a patient with severe back pain due to an osteolytic spinal metastatic tumor that had not responded to radiation therapy but which responded successfully to pain relief by a percutaneous vertebroplasty.

A Study for Minimum Volumes of Bicarbonate to Cause Precipitation of the Domestic Lidocaines / 대한마취과학회지

BACKGROUND: When local anesthetics for regional anesthesia is used, usually small amounts of bicarbonate are added for rapid onset. This addition gives the mixed solution a more alkaline pH. The following result is an increased unionized form of the local anesthetic and rapid penetration of the drug into tissue. Unfortunately, no data about adequate mixing volumes of domestic lidocaine and bicarbonate is available. METHODS: We examined six mixing pairs of two kinds of 2% lidocaines and three kinds of 8.4% bicarbonates for minimum volumes of bicarbonate to cause a precipitation of 2% 20 ml lidocaine. RESULTS: The mean volumes of bicarbonate to cause precipitation were 1.54 ml for Kwang-Myung lidocaine with Kwang-Myung bicarbonate, 2.90 ml for Kwang-Myung lidocaine with Dae-Won bicarbonate, 2.73 ml for Kwang-Myung lidocaine with Je-Il bicarbonate, 0.97 ml for Je-Il lidocaine with Kwang-Myung bicarbonate, 1.26 ml for Je-Il lidocaine with Dae-Won bicarbonate and 1.39 ml for Je-Il lidocaine with Je-Il bicarbonate. CONCLSIONS: We conclude that the Kwang-Myung lidocaine and the Je-Il lidocaine could cause precipitation when mixing with a smaller bicarbonate volume than foreign textbook recommended.