A prospective randomised trial comparing insertion success rate and incidence of catheterisation-related complications for subclavian venous catheterisation using a thin-walled introducer needle or a catheter-over-needle technique.

In clinical practice, both a thin-walled introducer needle and catheter-over-needle technique can be used to allow insertion of a guidewire during central venous catheterisation using the Seldinger technique. We compared the incidence of catheterisation-related complications (arterial puncture, haemothorax, pneumothorax, haematoma and catheter tip malposition) and insertion success rate for these two techniques in patients requiring right-sided subclavian central venous catheterisation. A total of 414 patients requiring infraclavicular subclavian venous catheterisation were randomly allocated to either a thin-walled introducer needle (needle group, n = 208) or catheter-over-needle technique (catheter group, n = 206). The catheterisation-related complication rate was lower in the needle group compared with the catheter group (5.8% vs. 15.5%; p = 0.001). Overall insertion success rates were similar (97.1% and 92.7% in the needle and catheter groups respectively; p = 0.046), although the first-pass success rate was higher in the needle group (62.0% vs. 35.4%; p < 0.001). We recommend the use of a thin-walled introducer needle technique for right-sided infraclavicular subclavian venous catheterisation.

Efficacy and safety of micafungin for the prophylaxis of invasive fungal infection during neutropenia in children and adolescents undergoing allogeneic hematopoietic SCT.

The objective of this study was to evaluate the efficacy and safety of micafungin for the prevention of invasive fungal infection (IFI) during the neutropenic phase of allogeneic hematopoietic SCT (allo-HSCT) in children and adolescents. This was a prospective, multicenter, open-label, single-arm study. Micafungin was administered i.v. at a dose of 1 mg/kg/day (max 50 mg) from the beginning of conditioning until neutrophil engraftment. Treatment success was defined as the absence of proven, probable, possible or suspected IFI through to 4 weeks after therapy. From April 2010 to December 2011, 155 patients were enrolled from 11 institutions in Korea, and 147 patients were analyzed. Of the 147 patients, 121 (82.3%) completed the protocol without premature interruption. Of the 132 patients in whom micafungin efficacy could be evaluated, treatment success was achieved in 119 patients (90.2%). There was no proven fungal infection in any patient. The number of patients with probable, possible and suspected IFI was two, two and nine, respectively. Thirty-five patients (23.8%) experienced 109 adverse events (AEs) possibly related to micafungin. No patients experienced grade IV AEs. Two patients (1.4%) discontinued micafungin administration due to adverse effects. None of the deaths were related to the study drug.

Inflammatory responses and morphological changes of radiofrequency-induced rat sciatic nerve fibres.

BACKGROUND: Recently, the pulsed radiofrequency (PRF, pulsed fashion) procedure was introduced for neuropathic pain management. Since PRF-induced lesions do not need high temperature compared with conventional continuous RF (CRF)-induced lesions, there is no significant loss of sensory fibres after application. METHODS: The progressive changes in the expression of eight representative inflammatory cytokines - glial fibrillary acidic protein, tumour necrosis factor alpha, interleukin-6, cyclooxygenase-II, inducible nitric oxide synthase, nuclear factor-κB, monocyte chemoattractant protein-1 and macrophage inflammatory protein-1α - as well as the morphological changes in extracellular matrices by Masson's trichrome and Verhoeff-van Gieson staining and atomic force microscopy were assessed for normal (control), sham (no RF current), PRF and CRF (positive control) rats. The RF procedure used in this study was similar to the methods used in human clinical trials. RESULTS: All proposed inflammatory proteins showed up-regulation after RF thermal treatments. Specifically, PRF-treated rats showed recovery of up-regulated inflammatory cytokines on day 30 after application, while CRF rats showed significant up-regulation that persisted until day 30. The control and sham groups showed normal unmyelinated axon and collagen structures. PRF-induced lesions showed less fibre destruction than CRF-induced lesions. PRF-induced lesions also showed mild axonal damage and little swelling of the mitochondria. CRF-induced lesions showed ultrastructural changes of sciatic nerve fibres that were irreversible. CONCLUSIONS: PRF-induced pain relief may be due to temporary blockage of nerve signals through the nerve pathway responsible for reversible neuronal depression. However, CRF-induced pain relief may be due to permanent blockage of nerve signals through other nerve pathways. Therefore, CRF could be applied to chronic inflammatory models used to study the mechanism of neuropathic pain.

Mycobacterial HBHA induces endoplasmic reticulum stress-mediated apoptosis through the generation of reactive oxygen species and cytosolic Ca2+ in murine macrophage RAW 264.7 cells.

Mycobacterial heparin-binding haemagglutinin antigen (HBHA) is a virulence factor that induces apoptosis of macrophages. Endoplasmic reticulum (ER) stress-mediated apoptosis is an important regulatory response that can be utilised to study the pathogenesis of tuberculosis. In the present study, HBHA stimulation induced ER stress sensor molecules in a caspase-dependent manner. Pre-treatment of RAW 264.7 cells with an IκB kinase 2 inhibitor reduced not only C/EBP homology protein expression but also IL-6 and monocyte chemotactic protein-1 (MCP-1) production. BAPTA-AM reduced both ER stress responses and caspase activation and strongly suppressed HBHA-induced IL-6 and MCP-1 production in RAW 264.7 cells. Enhanced reactive oxygen species (ROS) production and elevated cytosolic [Ca(2+)]i levels were essential for HBHA-induced ER stress responses. Collectively, our data suggest that HBHA induces cytosolic [Ca(2+)]i, which influences the generation of ROS associated with the production of proinflammatory cytokines. These concerted and complex cellular responses induce ER stress-associated apoptosis during HBHA stimulation in macrophages. These results indicate that the ER stress pathway has an important role in the HBHA-induced apoptosis during mycobacterial infection.

A laboratory study of the effects of processing blood through a cell salvage device and leucocyte depletion filter on levels of pro-inflammatory cytokines and bradykinin.

We investigated changes in concentrations of interleukin-1ß, interleukin-6, tumour necrosis factor-α and bradykinin in blood during passage through a cell salvage device and a leucocyte depletion filter, with or without application of subatmospheric pressure across the filter. Blood samples from 19 healthy women undergoing scheduled caesarean section showed concentrations of cytokines and bradykinin in blood filtered under gravity flow that were equal to or significantly lower than those of pre-operative venous blood samples. They were also significantly lower than that in postoperative orthopaedic shed blood, which is commonly reinfused after orthopaedic surgery. A minority of samples taken from blood that had been filtered using subatmospheric pressure showed raised interleukin-6 concentrations. We suggest that use of a leucocyte depletion filter for cell-salvaged blood with gravity flow is likely to be safe with regard to concentrations of cytokines and bradykinin. However, this may not hold true for the filter used with subatmospheric pressure. If transfusion of salvaged blood using a leucocyte depletion filter seems to induce hypotension, elevation of interleukin-6 should be suspected.

Combined treatment with celecoxib and sevoflurane after global cerebral ischaemia has no additive neuroprotective effects in rats.

BACKGROUND: The purpose of this study was to investigate whether combined administration of celecoxib and sevoflurane after ischaemia produces additive neuroprotection against transient global cerebral ischaemia in rats. METHODS: Cerebral ischaemia was induced by bilateral common carotid artery occlusion with haemorrhagic hypotension for 8 min. After ischaemia, no drugs were administered in the sham (n=4) and control (n=10) groups. In the celecoxib group (n=10), celecoxib 2 mg kg(-1) was administered after reperfusion. In the sevoflurane group (n=10), after reperfusion, sevoflurane 2.4% was inhaled two times for 5 min each at an interval of 10 min to achieve postconditioning. In the celecoxib+sevoflurane group (n=10), administration of celecoxib 2 mg kg(-1) and the sevoflurane postconditioning were performed simultaneously. Necrotic or apoptotic cells were examined in the hippocampus 7 days after ischaemia. Serum levels of proinflammatory cytokines including tumour necrosis factor-α and interleukin-1ß were measured 2 h, and 3 and 7 days after ischaemia. RESULTS: Necrotic or apoptotic cells were observed more frequently in the control group than in the celecoxib or sevoflurane groups 7 days after ischaemia (P<0.05). Cytokine levels were higher in the control group when compared with the celecoxib or sevoflurane groups 2 h after ischaemia (P<0.05). However, the histological outcomes and cytokine levels were similar in all three groups treated with celecoxib or sevoflurane. CONCLUSIONS: Combined treatment with celecoxib and sevoflurane after global cerebral ischaemia has no additive neuroprotective effects in rats.

Relationship between positive end-expiratory pressure and internal jugular vein cross-sectional area.

BACKGROUND: Application of positive end-expiratory pressure (PEEP) has been used to increase the cross-sectional area (CSA) of the right internal jugular vein (IJV) in order to facilitate catheterisation. We aimed to determine the PEEP level at which the maximum increase of CSA occurred. METHODS: We enrolled 60 American Society of Anesthesiologists physical status I and II patients undergoing general endotracheal anaesthesia. The CSA was measured in the supine position with no PEEP (control condition, P0) and after applying five different PEEPs in random order: 3 (P3), 6 (P6), 9 (P9), 12 (P12), and 15 (P15) cm H(2) O. Ultrasound was used to measure and record the CSA of the right IJV at the level of the cricoid cartilage. RESULTS: All PEEP levels increased the CSA of the right IJV relative to the control (all P < 0.05). On average, P3, P6, P9, P12, and P15 increased the CSA by 21.5, 37.4, 51.9, 66.5, and 72.4%, respectively. There was no significant increase in CSA above a PEEP of 12 cm H(2) O. CONCLUSION: The application of PEEP effectively increases the CSA of the right IJV. The PEEP giving the largest CSA is 12 cm H(2) O.

A novel PRKAR1A mutation in Korean Carney complex family.

Carney complex (CNC) is an autosomal dominant hereditary or sporadic multiple neoplastic syndrome that shows variable clinical symptoms. Generally, CNC appears as skin pigmentation, cardiac or cutaneous myxomas, and multiple endocrine tumours. We performed an extensive evaluation of 9 individuals within 1 family in whom CNC was suspected. Among them, 5 had CNC with various clinical manifestations. We also performed mutational analysis of suspected genes in these patients. Although all patients were members of the same family, variable CNC-related manifestations were observed in each patient. An analysis showed a novel deletion mutation (c.537delA) in exon 6 of the PRKAR1A gene in the patients. Based on our results, the patients were determined to have CNC type I. This is the first such mutational report in Korea.

Corrective osteotomy in forearm fracture malunion improves functional outcome in adults.

Malunions of forearm fractures in adults can present with limitation of forearm rotation, or as distal radioulnar joint instability with functional impairment. This contrasts with paediatric patients in whom malunions of similar severities are often better tolerated. We did a retrospective review of six adult patients after corrective forearm osteotomy for symptomatic malunited forearm shaft fractures. The corrective operations were done between 7 and 168 months after initial injury, using oblique or wedge osteotomies. Median follow-up was 22.5 months. The patients recovered well, with statistically significant improvement in forearm rotation and Disabilities of the Arm, Shoulder, and Hand (DASH) scores. No significant complications occurred.

The effect of remote ischaemic preconditioning on myocardial injury in patients undergoing off-pump coronary artery bypass graft surgery.

In several recent clinical trials on cardiac surgery patients, remote ischaemic preconditioning (RIPC) showed a powerful myocardial protective effect. However the effect of RIPC has not been studied in patients undergoing off-pump coronary artery bypass graft surgery. We evaluated whether RIPC could induce myocardial protection in off-pump coronary artery bypass graft surgery patients. Patients undergoing elective off-pump coronary artery bypass graft surgery were randomly allocated to the RIPC (n = 65) or control group (n = 65). After induction of anaesthesia, RIPC was induced by four cycles of five-minute ischaemia and reperfusion on the upper limb using a pneumatic cuff. Anaesthesia was maintained with sevoflurane, remifentanil and vecuronium. Myocardial injury was assessed by troponin I before surgery and 1, 6, 12, 24, 48 and 72 hours after surgery. There were no statistical differences in troponin I levels between RIPC and control groups (P = 0.172). Although RIPC reduced the total amount of troponin I (area under the curve of troponin increase) by 26%, it did not reach statistical significance (RIPC group 53.2 +/- 72.9 hours x ng/ml vs control group 67.4 +/- 97.7 hours x ng/ml, P = 0.281). In this study, RIPC by upper limb ischaemia reduced the postoperative myocardial enzyme elevation in off-pump coronary artery bypass graft surgery patients, but this did not reach statistical significance. Further study with a larger number of patients may be needed to fully evaluate the clinical effect of RIPC in off-pump coronary artery bypass graft surgery patients.

Management outcome and the role of manipulation in slipped capital femoral epiphysis.

PURPOSE: To examine and compare treatment outcomes for slipped capital femoral epiphysis (SCFE). METHODS: 24 patients with acute or acute-on-chronic SCFE underwent preoperative traction, 13 of them followed by in situ screw fixation (group A), and the remaining 11, manipulation with screw fixation (group B). Their treatment outcomes (according to the Aadalen criteria) and complications were compared. RESULTS: There were 2 treatment failures and one poor outcome in patients with acute SCFE (2 had avascular necrosis and one had slight pain with mild limitation of hip movement). The risk of developing avascular necrosis was significantly higher in patients with acute rather than acute-on-chronic or chronic slips. No significant differences were evident between groups A and B with regard to age, sex, ethnicity, outcomes, and preoperative and postoperative changes in the Southwick headshaft angle. CONCLUSION: Patients with acute or acute-on-chronic SCFE can be safely managed with straight-leg traction for up to 6 days, followed by in situ screw fixation without manipulation. Manipulation is not recommended in such slips, due to a higher avascular necrosis risk.

The effect of thalidomide on spinal cord ischemia/reperfusion injury in a rabbit model.

STUDY DESIGN: Randomized study. OBJECTIVES: To evaluate the effects of thalidomide on spinal cord ischemia/reperfusion injury via reduced TNF-alpha production. SETTING: Animal experimental laboratory, Clinical Research Institute of Seoul National University Hospital, Seoul, Korea. METHODS: Spinal cord ischemia was induced in rabbits by occluding the infrarenal aorta. Rabbits in group N did not undergo ischemic insult, but rabbits in groups C (the untreated group), THA, and THB underwent ischemic insult for 15 min. The THA and THB groups received thalidomide (20 mg/kg) intraperitoneally (i.p.) before ischemia, but only the THB group received thalidomide (i.p., 20 mg/kg) after 24 and 48 h of reperfusion. After evaluating neurologic functions at 1.5 h, 3, and 5 days of reperfusion, rabbits were killed for histopathologic examination and Western blot analysis of TNF-alpha. RESULTS: The THA and THB groups showed significantly less neurologic dysfunction than the C group at 1.5 h, 3, and 5 days of reperfusion. The number of normal spinal motor neurons in ventral gray matter was higher in THA and THB than in C, but no difference was observed between THA and THB. Western blot analysis showed a significantly higher level of TNF-alpha in C than in THA and THB at 1.5 h of reperfusion, but no difference was observed between C, THA, or THB at 3 or 5 days of reperfusion. CONCLUSION: Thalidomide treatment before ischemic insult reduces early phase ischemia/reperfusion injury of the spinal cord in rabbits.

The effect of esmolol-induced controlled hypotension in combination with acute normovolemic hemodilution on cerebral oxygenation.

BACKGROUND: It is possible to perform acute normovolemic hemodilution (ANH) in combination with controlled hypotension (CH). In this randomized prospective study, we examined the effect of the combination of ANH and CH on cerebral oxygenation using near-infrared spectroscopy. METHODS: Fifty-six patients undergoing major orthopedic surgery were randomly assigned to either group A (ANH only) or group CH (CH in combination with ANH). In group CH, CH was induced with esmolol. The regional cerebral oxygen saturation (rSO(2)) was monitored continuously and was compared between the two groups before and after ANH, 30 min (OP(30)) and 90 min (OP(90)) after the beginning of surgery and after the completion of surgery. RESULTS: The value of rSO(2) was the same in both groups in the absence of CH (at baseline: group A, 70.1 +/- 6.0%; group CH, 69.9 +/- 6.7%; after surgery: group A, 64.5 +/- 4.9%; group CH, 64.3 +/- 5.8%). However, in the presence of CH, rSO(2) values were significantly lower in group CH than in group A (at OP(30): group A: 60.4 +/- 3.4%; group CH, 55.9 +/- 7.3%; P < 0.01; at OP(90): group A, 58.3 +/- 5.2%; group CH, 53.5 +/- 6.5%; P < 0.001). The number of patients with rSO(2) < 50% was significantly higher in group CH (14.3%) than in group A (3.8%). CONCLUSION: ANH in combination with esmolol-induced CH causes a significant decrease in cerebral oxygen saturation compared with ANH alone.

Seizure control of Gamma Knife radiosurgery for non-hemorrhagic arteriovenous malformations.

OBJECTIVES: Although radiosurgery has been found to be a safe and effective alternative treatment, seizure outcome of arteriovenous malformation (AVM) radiosurgery has not been documented in detail. We report the effect of Gamma Knife radiosurgery (GKRS) on seizures associated with AVMs and discuss the various factors that influence the prognosis. MATERIAL AND METHODS: Between 1992 and 2004, 246 patients were treated with GKRS for AVMs at Kyung-Hee medical center. Forty five (17.0%) patients have non-hemorrhagic AVMs and presenting symptom was seizure. Two patients of all were excluded from this study due to loss of follow-up after radiosurgery. In this study, retrospective analysis of clinical characteristics, radiologic findings, radiosurgical seizure outcome were performed. RESULTS: There were 32 male and 11 female with age ranging from 10 to 74 years (mean 35 years). Type of seizure included: general tonic clonic (n = 28); focal motor or sensory (n = 7); partial complex (n = 8). The location of AVM was temporal (n = 18); frontal (n = 9); deep seated (n = 7): parietal (n = 5); occipital (n = 4). Follow-up period was from 8 months to 12 years (mean 46 months). Mean volume was 6.2 cc (2.7-20), mean marginal and maximal dosage was 19.5 (17-26) and 36.6 Gy (13-50). During follow-up after radiosurgical treatment, 23 (53.5%) of 43 patients were seizure-free, 10 (23.3%) had significant improvement, were unchanged in 8 (18.6%) and aggravated in 2 (4.6%) patients. In 33 patients, follow-up angiography or MRI was performed. Complete obliteration was achieved in 16 (49.0%) patients, partial obliteration in 13 (39.0%). Four were unchanged (12.0%). Of 33 patients with follow-up performed, 26 were followed for over 2 years. Eleven (84.6%) of 13 patients with complete obliteration were seizure-free (p < 0.005). Four (36.3%) of 13 with partial obliteration and unchanged remained seizure-free. Fifteen patients had experienced intractable seizure before radiosurgery. After radiosurgery, seizures disappeared in 8 (53%) patients. Seizure frequently decreased in 5 (33%) and 2 patients (14%) were unchanged but none was aggravated. Five (71%) of 7 patients with complete obliteration were seizure-free and 2 (40%) of 5 patients with partial obliteration were seizure-free. CONCLUSION: Up to now, controversy about resective surgery or radiosurgery as treatment of seizure related to AVMs still remains. In this study, we experienced that Gamma Knife radiosurgery is commonly performed to treat AVMs and can improve symptomatic seizure associated with AVMs. To clarify the mechanism of seizure control in AVMs radiosurgery is difficult, but it seems to be closely related to hemodynamic effects after radiosurgery.

Intrathecal clonidine does not reduce post-spinal shivering.

BACKGROUND: After general or epidural anesthesia, clonidine is known to be effective in suppressing established shivering. The aim of this study was to assess the preventive effect of intrathecal clonidine on post-spinal shivering compared with intravenous (i.v.) clonidine. METHODS: One hundred and fifty patients scheduled for orthopedic surgery were randomly allocated into three groups to receive either 1 microg/kg clonidine i.v. (IV group) or the same volume of isotonic saline (control and IT groups) at 5 min before spinal anesthesia. Spinal anesthesia was performed with 12-15 mg hyperbaric bupivacaine 0.5% plus either 1 ml of saline (control and IV groups) or 150 microg clonidine (IT group). Shivering was evaluated for a period of 90 min and graded as none, mild, moderate, and severe. RESULTS: Twenty patients (40%) in the control group and 17 patients (34%) in the IT group showed shivering compared with four (8%) in the IV group. Patients with moderate-to-severe shivering were only seen in the control and IT group, and the maximal intensity of shivering was not different between the two groups. Patients in the IV group were significantly more sedated than the other groups. CONCLUSIONS: The intrathecal administration of clonidine 150 microg fails to prevent post-spinal shivering; by contrast, we have confirmed that i.v. clonidine 1 microg/kg is an effective method to prevent shivering in patients undergoing spinal anesthesia for orthopedic surgery.

Comparison of alfetanil and ketamine in combination with propofol for patient-controlled sedation during fiberoptic bronchoscopy.

BACKGROUND: During fiberoptic bronchoscopy, propofol, ketamine, benzodiazepines, and opiates are most commonly used, alone or in combination for sedation. The aim of this study was to compare the clinical efficacy of propofol/ketamine with propofol/alfentanil for patient-controlled sedation (PCS) during fiberoptic bronchoscopy. METHOD: Patients undergoing fiberoptic bronchoscopy were randomly assigned to receive either propofol/alfentanil (PA group; n = 138) or propofol/ketamine (PK group; n = 138) via a patient-controlled analgesia (PCA) device for sedation and analgesia. Changes in blood pressure, heart rate (HR), and oxygen saturation were monitored. Degree of patient and bronchoscopist satisfaction was evaluated using a 10-cm visual analog scale (VAS) (0 = extremely uncomfortable to 10 = extremely comfortable). RESULTS: After sedation, systolic arterial pressure (SAP) decreased in the PA group, but SAP was stable in the PK group. Compared with values immediately before starting bronchoscopy, SAP and HR increased during the procedure in both groups (P < 0.05). Patients in the PK group showed more satisfaction [(9.5 (6-10) vs. 9.0 (6-10)), P < 0.05] and amnesia (82% vs. 61%, P < 0.01). Despite these differences, the majority (greater than 90%) of the patients in both groups stated that they were comfortable during the procedure. CONCLUSION: Our results show that although both techniques proved effective for sedation in patients undergoing fiberoptic bronchoscopy, ketamine is superior to alfentanil when used in combination with propofol because of the high patient satisfaction and amnesia.

Combined use of autologous transfusion techniques to avoid allogeneic transfusion in spinal fusion surgery with instrumentation.

This study conducted a retrospective review of the medical records of 321 patients to delineate the efficacy of the combined use of autologous transfusion (AT) techniques. Transfusion profiles between an AT and homologous transfusion (HT) group were compared. A much lower proportion of patients were exposed to allogeneic blood in the AT group (13%) than in the HT group (98%, p<0.001). In the AT group, a significantly smaller proportion of patients were exposed to allogeneic blood in patients transfused with three or four AT techniques (8%) than those with one or two techniques (29%, p<0.05). A febrile reaction (11% of patients) after a reinfusion of post-operatively shed blood was the only side effect associated with an AT. In conclusion, an AT is effective for preventing the exposure of allogeneic blood in spinal fusion surgery. The combined use of multiple AT techniques may further improve its efficacy.

Coronary artery spasm induced by carotid sinus stimulation during neck surgery.

We observed four transient episodes of marked ST-segment elevation in a 58-yr-old man with no history of coronary artery disease undergoing resection of a metastatic neck mass under general anaesthesia. Elevations of the ST segment were abrupt, with no change in arterial pressure or heart rate, and resolved spontaneously. When the carotid sinus was compressed directly, ST-segment elevation was noted 1 min after the onset of stimulation. After surgery, coronary angiography showed diffuse, slight narrowing of the distal bed of the posterolateral branch of the right coronary artery. Ergonovine caused total occlusion of the posterolateral branch of the right coronary artery with chest pain and ST-segment elevation, confirming the diagnosis of variant angina. The coronary artery spasm seems to have been provoked by vagal activation from carotid sinus stimulation during general anaesthesia.

Clinical trial of esmolol-induced controlled hypotension with or without acute normovolemic hemodilution in spinal surgery.

BACKGROUND: Drug-induced controlled hypotension (CH) combined with acute normovolemic hemodilution (ANH) is being widely used for blood conservation in surgical patients. The purpose of this study was to investigate the efficacy and safety of esmolol-induced CH combined with ANH (hematocrit down to 28%). METHODS: Thirty patients who were scheduled to receive spinal surgery were randomly divided into two groups: an esmolol-induced CH alone group (esmolol group, n=15) and a CH-ANH combined group (E-ANH group, n=15). Controlled hypotension was induced with esmolol 500 micro g/kg, followed by a continuous infusion of 0-300 micro g/kg/min to maintain mean arterial pressure at 55-65 mmHg. RESULTS: The mean infusion rate of esmolol in the esmolol-ANH group was 46+/-6 micro g/kg/min (mean+/-SD), which was significantly lower than the 77+/-9 micro g/kg/min used in the esmolol group (P<0.05). The number of units of homologous blood (packed RBC) transfused perioperatively was 2.2+/-0.6 units in the esmolol-ANH group, which was significantly less than 4.3+/-0.4 units used in the esmolol group (P<0.01). While O2 delivery decreased significantly during CH, O2 consumption remained unchanged in both groups. No complications resulted from CH or ANH in any of the groups. CONCLUSION: Our data suggest that ANH of moderate degree can be combined with esmolol-induced CH to improve blood conservation in surgical patients.

Coiling of lumbar epidural catheters.

BACKGROUND: The difficulties in threading an epidural catheter to vertebral levels remote to the puncture level have been well documented. This study was undertaken to determine the length that a single orifice epidural catheter can be threaded into the lumbar space without coiling (coiling length), and whether this is affected by the direction of the epidural needle bevel. METHODS: Forty-five young male patients scheduled for surgery under epidural analgesia were enrolled. The epidural space was identified using a midline approach at the L(2-3) or L(3-4) interspace with the loss of resistance to air technique. A 19-G single-orifice epidural catheter (Flextip Plus, Arrow International, Inc, Reading, PA, USA) was inserted through a Tuohy needle oriented either cephalad (n=20) or caudad (n=25). During insertion, the path and the position of the catheter tip was determined by fluoroscopy using iohexol dye. RESULTS: The median coiling length was 2.8 cm, ranging from 1.0 to 8.0 cm. Only 13% of epidural catheters could be threaded 4 cm beyond the tip of the needle without coiling. No significant difference was found in coiling length between the cephalad group (2.9 cm) and the caudad group (2.5 cm). CONCLUSION: This study demonstrates that coiling length is independent of whether the bevel of the Tuohy needle is directed cephalad or caudad. We recommend that an optimal insertion depth of an end-hole single orifice catheter is 3 cm.