Epidural Catheter Migration Associated with Patient Movement / 대한마취과학회지

BACKGROUND: A properly placed epidural catheter tip may become displaced out of the epidural space after being secured as a result of patient movement, a common cause of inadequate analgesia. This study was performed to evaluate the migration of an epidural catheter with patient movement. METHODS: Forty-six parturients planning to undergo a cesarean section under epidural anesthesia were enrolled. Patients were divided into two groups according to body mass index (BMI): 26 kg/m2. A 19-gauge single-orifice epidural catheter (Flextip Plus(TM), Arrow, USA) was inserted at the L(2-3) or L(3-4) interspace with the patient in the sitting flexed position. The distance to the epidural space and length of catheter position change was measured before the catheter was secured to the skin, as the patient moved from the sitting flexed to sitting upright and then to the lateral decubitus position with flexion and extension. RESULTS: Catheters were drawn inward with position change from the sitting flexed to lateral decubitus position, the magnitude increasing with BMI (0.73 +/- 0.40 cm vs. 0.98 +/- 0.35 cm). CONCLUSIONS: This study shows that the indrawing of the catheter with reference to the skin occurs as a patient changes position, and this indrawing can result in catheter dislodgement out of the epidural space.

The Effect of Adding Low-Dose Ketamine to a Patient-Controlled Epidural Regimen / 대한마취과학회지

BACKGROUND: Ketamine is a noncompetitive antagonist that blocKs the ion channel coupled to the N-methyl-D-aspartate receptor. This class of drugs may be useful for treatment of acute postoperative pain due to prevention of central sensitization of nocieceptors. We examined the effect of adding Ketamine to a patient-controlled epidural analgesia (PCEA) regimen. METHODS: Sixty parturients undergoing a Cesarean section received lumbar epidural anesthesia using 0.75% ropivacaine with 50ng of fentanyl and a PCEA using 0.15% ropivacaine and 50ng/mL of butorphanol with the addition of Ketamine 50 mg (K50, n = 20), 100 mg (K100, n = 20), or without (control, n = 20). The PCEA device was programmed to deliver 4 mL of a regimen (total 300 mL of solution with 0.15% ropivacaine plus 50ng/mL of butorphanol) with a 10 minute locKout interval. Visual analogue pain score, side effects and PCEA drug consumption were checKed during 48 hours postoperatively. RESULTS: PCEA drug consumption and incidence of nausea and vomiting were decreased by 25% and 25% (K50) and 35% and 29% (K100) compared with the control group. The severity of sedation was increased in the K50, and K100 groups more than the control group (P < 0.05). There were no differences in visual analogue pain score and other side effects among the groups. CONCLUSIONS: We conclude that adding low-dose Ketamine in a PCEA regimen using ropivacaine and butorphanol decreases the consumption of the PCEA drug and the incidence of nausea and vomiting and increases the severity of sedation.

Differences of SpO2 at between Hand and Foot During Spinal and Lumbar Epidural Anesthesia / 대한마취과학회지

Pulse oxymetry noninvasively estimates arterial oxygen saturation (SaO2) spectrophoto- metically by processing a pulse added light absorbance signal from transilluminsted tissue and provides continuous information. So the device is rapidly becoming a standard in clini- cal monitoring. Preganglionic sympathetic denervation during spinal and lumbar epidural anesthesia causes dilatation of both resistance and capacitance veasels of the lower limbs, with a reflex increase in efferent sympathetic activity above the level of the block. Skin temperature elevation corresponds with the upper limit of diminished sympathetic activity and is in agreement with the view that skin temperature increase is a useful indicator of sympathetic blockade. Pulse oximetry is dependent upon the presence of a pulsating vascular bed. The signal detection will be impaired in the presence of vasoconstriction or venous congestion, conditions which occur in spinal and lumbar epidural anesthesia. We compared the oximetric measurements (SpO2) at the hand and the foot with arterial oxygen saturation (SaO2) during spinal and lumbar epidural anesthesia. After administration of a crystalloid solution, 10 patients recieved 7-10mg of 0.5% tetracaine into the subarachoid space and 10 patients recieved 10-20ml of 2% lidocaine into the lumbar epidural space in 20 adult patients, scheduled for operation. Two temperature probes and two pulse oximeter probes were applied to the finger snd toe of the patients, and the temperature and SpO2, values were recorded continuously. Arterial oxygen saturation (SaO2) was measured using M288 before and 30 min after the onset of sensory block. In all patients, intraoperative decreasing of heart rate and arterial blood pressure was 15% from baseline. During anesthesia, the decreasing of temperature reeorded from sympathetically unaffected areas could be related to vasoconstriction, counterbalancing sympathetic block. But no significant differences were detected between SaO2, and SpO2, basal values recorded from the hand and foot before anesthesia. After the onset of spinal and lumbsr epidural anesthesia, SpO, values recorded from tbe hand were not changed aignificantly. Otherwise significant differences in SaO2 were detected between two groups before and 30 min after anesthesis, because the age in lumbar epidural group (63.8+/-90.1) was older than the age in spinal group (44.6+/-121.1). Therefore, we concluded that SaO2 must be confirmed when there are clinically significant changes during spinal and lumbar epidural anesthesia, although SpO2 in hand are neither changed nor decreaaed below normal range.