Complications and Technical Consideration of Ultrasound-Guided Rectus Sheath Blocks: A Retrospective Analysis of 4033 Patients.

BACKGROUND: Although the ultrasound-guided rectus sheath block (RSB) is usually regarded as an easy and safe procedure in clinical settings, there is currently no report on complications incidence. Therefore, the present study investigated complications in a large cohort and described the technical considerations to minimize complications of real-time ultrasound-guided RSBs. METHODS: This was a retrospective cohort study of patients who underwent real-time ultrasound-guided RSBs for perioperative pain control in laparoscopic surgery with an umbilical port between February 1, 2017, and February 28, 2021, at the Asan Medical Center in South Korea. All RSBs were performed bilaterally using a 23-gauge Quincke needle, and a bilateral 2-block placement was regarded as 1 RSB. Patient data, including demographics, preoperative laboratory data, preoperative antiplatelet or anticoagulant medication with the duration of discontinuation, and type of surgery, were collected to show the study population characteristics and explore potential factors associated with adverse events such as hematoma. Ultrasound images of patients and adverse events of RSBs, including extrarectus sheath injections, vascular injuries, bowel injury, or local anesthetic systemic toxicity, were also analyzed accordingly. RESULTS: A total of 4033 procedures were analyzed. The mean body mass index of the patients was 24.1 (21.8-26.5) kg/m2. The preoperative laboratory data were within normal range in 4028 (99.9%) patients. Preoperative antiplatelets or anticoagulants were administered in 17.3% of the patients. Overall, 96 complications (2.4%) were observed. Among them, extrarectus sheath injection occurred in 88 cases (2.2%), which included preperitoneal injection (0.9%) and intraperitoneal injection (1.3%). Vascular injuries constituted 8 cases (0.2%) and all vascular injuries resulted in hematoma: 7 cases of inferior epigastric artery injury with rectus sheath hematoma and 1 of inferior mesenteric artery injury with retroperitoneal hematoma. Bowel injury or local anesthetic systemic toxicity was not reported. CONCLUSIONS: In this study of RSBs performed on 4033 patients using a 23-gauge Quincke needle in patients with low body mass index, there were 8 cases (0.2%) of vascular injury, all of which accompanied hematoma.

Atrioventricular conduction disturbances immediately after hepatic graft reperfusion and their outcomes in patients undergoing liver transplantation.

Hemodynamic perturbation during hepatic graft reperfusion in patients undergoing liver transplantation (LT) is challenging and is frequently accompanied by bradyarrhythmia and even asystole. However, detailed data on electrocardiographic (ECG) changes during reperfusion are almost nonexistent, although the correct diagnosis by record is important for the treatment. We aimed to identify ECG rhythm disturbances during graft reperfusion and to investigate risk factors and outcomes. Data from 1065 consecutive patients who underwent adult LT were analyzed. The incidence, type, and detailed characteristics of ECG changes immediately after graft reperfusion were assessed using an electronically archived intraoperative ECG database. We analyzed risk factors, postoperative outcomes including major cardiovascular events, 30-day and 1-year mortalities of recipients based on the occurrence of atrioventricular (AV) block, and asystole during reperfusion. The typical pattern of postreperfusion bradyarrhythmia was progressive PR interval prolongation until a Mobitz type 1 AV block occurred. The overall incidence of AV block was 5.0% (53/1065), and 30.2% of them (16/53) had initiated as AV block and then progressed into ventricular asystole. Fulminant hepatic failure was a significant predictor for occurrence of AV block (odds ratio [OR], 7.20; 95% confidence interval, 3.38-15.32; P < 0.001). Patients with AV block showed significantly higher incidence of postoperative major cardiovascular events (P < 0.001) and 30-day mortality (P = 0.002) than those without AV block, whereas the 1-year mortality was not different between the 2 groups (P = 0.10). The postreperfusion asystole was consistently preceded by a Mobitz type 1 AV block. The occurrence of AV block and asystole appears to be an important prognosticator. Therefore, maintaining an optimal range of physiological status and gradual unclamping of the vena cava to avoid sudden atrial distension are recommended in high-risk patients during reperfusion period. Liver Transplantation 22 956-967 2016 AASLD.

A proposal of a simple epidural simulator for training novice anesthesiologists.

PURPOSE: Confirming the epidural space during epidural anesthesia relies mainly on feel and experience, which are difficult techniques for a trainee to learn. We designed an epidural simulator for trainees to experience loss of resistance (LOR) and various degrees of pressure resistance. METHODS: The simulator consists of a Perifix(®) LOR syringe and 1-, 5-, 10- and 50-mL syringes assembled by three-way stopcocks. A total of 89 anesthesiologists evaluated the simulator, given the choice of either the intermittent technique with air or continuous technique with saline. Sudden LOR and applicability of the simulator for training purposes were assessed using the numerical rating score (NRS). Pressure resistance at each lumbar structure was evaluated by the anesthesiologists using the intermittent technique with air. RESULTS: Seventy-four anesthesiologists used the intermittent technique with air and 15 used the continuous technique with saline. The NRSs for sudden LOR and the applicability for training purposes were 8 and 9 (median), respectively. The pressure resistance to a 50-mL syringe was regarded as the epidural space (odds ratio 602.3 for 5-mL syringe and 144.4 for 10-mL syringe) by 89 % of anesthesiologists using air for LOR. Resistance to the 10-mL syringe was most frequently considered as muscle, subcutaneous fat, or the interspinous ligament, while resistance to the 1-mL syringe was considered as the ligamentum flavum (odds ratio 2.3 for 5-mL syringe and 18.6 for 10-mL syringe). CONCLUSIONS: Our epidural simulator is a simple, low-cost device that can be easily constructed. It was shown to provide valid haptic feedback as a promising tool for training novice anesthesiologists.

Real-time ultrasound guidance versus fluoroscopic guidance in thoracic epidural catheter placement: a single-center, non-inferiority, randomized, active-controlled trial.

INTRODUCTION: Fluoroscopy can improve the success rate of thoracic epidural catheter placement (TECP). Real-time ultrasound (US)-guided TECP was recently introduced and showed a high first-pass success rate. We tested whether real-time US-guided TECP results in a non-inferior first-pass success rate compared with that of fluoroscopy-guided TECP. METHODS: In this single-center, non-inferiority, randomized trial, the primary outcome was the comparison of the first-pass success rate of TECP between real-time US guidance (US group) and fluoroscopic guidance (fluoroscopy group). Secondary outcomes included time to identifying epidural space, procedure time, total number of needle passes, number of skin punctures, final success, and cross-over success. RESULTS: We randomly assigned 132 patients to the allocated groups. The difference in the first-pass success rate between the groups did not exceed the non-inferiority margin of 15% (US group: 66.7% vs fluoroscopy group: 68.2%; difference -1.5%, 95% exact CI: -14.9% to 11.9%). The difference in the final success rate also did not differ between the groups (98.5% vs 100.0%; difference -1.5%, 95% exact CI: -4.0% to 1.0%). The time to identifying epidural space (45.6 (34-62) vs 59.0 (42-77) s, p=0.004) and procedure time (39.5 (28-78) vs 112.5 (93-166) s, p<0.001) were significantly shorter in the US group. CONCLUSIONS: Real-time US guidance provided a non-inferior success rate and shorter time spent on preparation and procedure compared with fluoroscopic guidance in TECP. TRIAL REGISTRATION NUMBER: KCT0006521.

Preemptive visceral analgesic effect of thoracic paravertebral block on postoperative opioid consumption in patients undergoing laparoscopic cholecystectomy: a prospective, randomized, assessor-blind study.

BACKGROUND: The preemptive visceral analgesic effect of regional nerve block has not been adequately investigated to date. We evaluated the preemptive visceral analgesic effect of thoracic paravertebral block (TPVB) in patients undergoing laparoscopic cholecystectomy (LC) in whom pre-incisional rectus sheath block (RSB) was used to minimize somatic surgical pain. METHODS: In this prospective, randomized, assessor-blind study, 70 patients scheduled for elective LC were randomly assigned to the pre-TPVB (n = 35) or the post-TPVB (n = 35) group. Both groups received pre-incisional RSB, and patients in the pre-TPVB group received TPVB before skin incision while those in the post-TPVB group received TPVB after skin closure. The primary outcome was the total rescue analgesic consumption (morphine equianalgesic dose) during the 24 h post-surgery. The secondary outcomes were the cumulative analgesic consumption and pain intensity for 24 h after surgery, and adverse events. RESULTS: Pre-TPVB significantly reduced total rescue analgesic consumption (estimated mean [95% CI]) during the 24 h after surgery than post-TPVB (16.9 [14.5, 19.3] vs. 25.3 [22.8, 27.7] mg, estimated difference: -8.3 [-11.8, -4.9], P < 0.001). The cumulative rescue analgesic consumption was significantly lower in the pre-TPVB group from 2-24 h after surgery (P < 0.001). The postoperative pain intensity was significantly lower in the pre-TPVB group as well at 0.5-6 h after surgery. There were no adverse events in both groups. CONCLUSIONS: Pre-incisional TPVB conferred a significant preemptive visceral analgesic effect in patients undergoing LC, and significantly reduced the amount of postoperative opioid consumption.

Exercise plus volume loading prevents orthostatic intolerance but not reduction in cerebral blood flow velocity after bed rest.

This study tested the hypothesis that reduction in cerebral blood flow (CBF) during orthostatic stress after bed rest can be ameliorated with volume loading, exercise, or both. Transcranial Doppler was used to measure changes in CBF velocity during lower body negative pressure (LBNP) before and after an 18-day bed rest in 33 healthy subjects. Subjects were assigned into four groups with similar age and sex: 1) supine cycling during bed rest (Exercise group; n = 7), 2) volume loading with Dextran infusion after bed rest to restore reduced left ventricular filling pressure (Dextran group; n = 7), 3) exercise combined with volume loading to prevent orthostatic intolerance (Ex-Dex group; n = 7), and 4) a control group (n = 12). LBNP tolerance was measured using a cumulative stress index (CSI). After bed rest, CBF velocity was reduced at a lower level of LBNP in the Control group, and the magnitude of reduction was greater in the Ex-Dex group. However, reduction in orthostatic tolerance was prevented in the Ex-Dex group. Notably, volume loading alone prevented greater reductions in CBF velocity after bed rest, but CSI was reduced still by 25%. Finally, decreases in CBF velocity during LBNP were correlated with reduction in cardiac output under all conditions (r(2) = 0.86; P = < 0.001). Taken together, these findings demonstrate that volume loading alone can ameliorate reductions in CBF during LBNP. However, the lack of associations between changes in CBF velocity and orthostatic tolerance suggests that reductions in CBF during LBNP under steady-state conditions by itself are unlikely to be a primary factor leading to orthostatic intolerance.

Comparison of sitting and prone positions for real-time ultrasound-guided thoracic epidural catheter placement: a randomized controlled trial.

INTRODUCTION: Real-time ultrasound-guided thoracic epidural catheter placement (US-TECP) has been recently introduced. Patient's position is associated with the success of spine interventions; however, the effects of position on the outcome of the procedure remain unknown. We aimed to assess the clinical usefulness of patient positioning during real-time US-TECP. METHODS: Patients were randomly assigned to the prone position group (group P) and sitting position group (group S). The primary outcome was needling time during the procedure. The secondary outcomes were time to mark space, total number of needle passes, number of skin punctures, first-pass success, final success, crossover success, and visibility of ultrasound (US) views. Global Rating Scale (GRS) score, Patient Comfort Scale score, procedural pain intensity, patient satisfaction, and procedure-related complications were also determined. RESULTS: Sixty-four patients were included in this study. The needling time was significantly shorter in group P than in group S (36.5 (26.5-51.0) vs 59.5 (34.5-152.0) s, p<0.01). The numbers of needle passes and skin punctures were significantly lesser in group P than in group S. First-pass success was higher in group P than in group S. Group P had higher GRS compared with group S. The time to mark space, final success, US visibility score, Patient Comfort Scale score, procedural pain intensity, and patient satisfaction did not differ between the groups. One patient in group S developed a vasovagal reaction. DISCUSSION: This study shows that prone position may be preferred for real-time US-TECP, considering its better clinical usefulness. TRIAL REGISTRATION NUMBER: KCT0005757.

Factors Associated With Rebound Pain After Patient-controlled Epidural Analgesia in Patients Undergoing Major Abdominal Surgery: A Retrospective Study.

OBJECTIVES: Although patient-controlled epidural analgesia (PCEA) is an effective form of regional analgesia for abdominal surgery, some patients experience significant rebound pain after the discontinuation of PCEA. However, risk factors for rebound pain associated with PCEA in major abdominal surgery remain unknown. This study evaluated the incidence of rebound pain related to PCEA and explored potential associated risk factors. MATERIALS AND METHODS: We performed a retrospective review of 236 patients using PCEA following hepatobiliary and pancreas surgery between 2018 and 2020 in a tertiary hospital in South Korea. Rebound pain was defined as an increase from well-controlled pain (numeric rating scale <4) during epidural analgesia to severe pain (numeric rating scale ≥7) within 24 hours of discontinuation of PCEA. Logistic regression analysis was performed to determine the factors associated with rebound pain. RESULTS: Patients were categorized into the nonrebound pain group (170 patients; 72%) and the rebound pain group (66 patients; 28%). Multivariable logistic regression analysis revealed that preoperative prognostic nutritional index below 45 (odds ratio=2.080, 95% confidential interval=1.061-4.079, P =0.033) and intraoperative transfusion (odds ratio=4.190, 95% confidential interval=1.436-12.226, P =0.009) were independently associated with rebound pain after PCEA discontinuation. DISCUSSION: Rebound pain after PCEA occurred in ~30% of patients who underwent major abdominal surgery, resulting in insufficient postoperative pain management. Preoperative low prognostic nutritional index and intraoperative transfusion may be associated with rebound pain after PCEA discontinuation.

Laboratory variables associated with low near-infrared cerebral oxygen saturation in icteric patients before liver transplantation surgery.

BACKGROUND: Although regional cerebral oxygen saturation (rSO2) measurements can detect disturbances in cerebral oxygenation, their usefulness is limited in patients with hyperbilirubinemia. We examined the relationship between rSO2 and other laboratory variables that may affect interpretation of low rSO2 in awake patients with end-stage liver disease before liver transplantation surgery. METHODS: Before induction of general anesthesia, rSO2 was measured in 164 patients with liver cirrhosis (Child class A/B/C = 19/41/104) and 8 with fulminant hepatic failure. Patients with West Haven hepatic encephalopathy of grade 3 or 4 were excluded. Relationships between rSO2 and laboratory variables were evaluated by correlation and multivariate regression, and by receiver operating characteristic curve analysis. RESULTS: Univariate analyses showed that rSO2 (median 58.5%, range 15% to 82%) correlated with serum total bilirubin, hemoglobin (Hb), creatinine, sodium, and magnesium concentrations, and prothrombin time (P < 0.001 each), but not with serum concentrations of glucose, albumin, potassium, and ammonia. Multiple logistic regression analysis showed that only elevated total bilirubin (range 0.4 to 66 mg/dL; odds ratio [OR] = 1.31; 95% confidence interval [CI] = 1.18 to 1.45) and low Hb (range 5.3 to 15.7 g/dL; OR = 0.21; 95% CI = 0.11 to 0.43) were independently related to rSO2 <50%. The optimum cutoff points for observing an rSO2 < 50% were total bilirubin >7.2 mg/dL (sensitivity 89%, specificity 90%) and Hb <9.6 g/dL (sensitivity 70%, specificity 82%). CONCLUSIONS: High total bilirubin and low Hb concentrations were independently associated with rSO2 values below 50% in end-stage liver disease patients awaiting liver transplantation. The results of this study identify patients in whom a low rSO2 may be an artifact rather than cerebral ischemia.

Adenosine triphosphate-sensitive potassium channel blockers attenuate the antiallodynic effect of R-PIA in neuropathic rats.

BACKGROUND: Nerve injury can generate neuropathic pain. The accompanying mechanical allodynia may be reduced by the intrathecal administration of adenosine. The neuroprotective effects of adenosine are mediated by the adenosine triphosphate (ATP)-sensitive potassium (K(ATP)) channel. We assessed the relationship between the adenosine A1 receptor agonist, N6-(R)-phenylisopropyl adenosine (R-PIA), and K(ATP) channels to determine whether the antiallodynic effects of R-PIA are also mediated through K(ATP) channels in a rat nerve ligation injury model of neuropathic pain. METHODS: Mechanical allodynia was induced by tight ligation of the left lumbar fifth and sixth spinal nerves. Mechanical allodynia in the left hindpaw was evaluated using von Frey filaments to measure withdrawal thresholds. R-PIA (0.5, 1, or 2 µg) was administered intrathecally to induce antiallodynia. We assessed whether pretreatment with the K(ATP) channel blockers glibenclamide or 5-hydroxydecanoate reversed the antiallodynic effect of R-PIA. Also, we evaluated whether diazoxide, a K(ATP) channel opener, had an antiallodynic effect and promoted the antiallodynic effect of R-PIA. Lastly, we investigated whether the voltage-activated K channel blocker 4-aminopyridine attenuated the effect of R-PIA. RESULTS: Intrathecal R-PIA produced maximal antiallodynia at 2 µg (P < 0.05). Intrathecal pretreatment with glibenclamide and intraperitoneal pretreatment 5-hydroxydecanoate significantly reduced the antiallodynic effect of R-PIA. Diazoxide produced an antiallodynic effect and also enhanced the antiallodynic action of R-PIA. 4-Aminopyridine had no effect on the antiallodynic action of R-PIA. CONCLUSIONS: The antiallodynic effects of adenosine A1 receptor stimulation may be related to K(ATP) channel activity in a rat model of nerve ligation injury.

Programmed Intermittent Epidural Bolus versus Continuous Epidural Infusion in Major Upper Abdominal Surgery: A Retrospective Comparative Study.

Although recent evidence shows that the programmed intermittent epidural bolus can provide improved analgesia compared to continuous epidural infusion during labor, its usefulness in major upper abdominal surgery remains unclear. We evaluated the effect of programmed intermittent epidural bolus versus continuous epidural infusion on the consumption of postoperative rescue opioids, pain intensity, and consumption of local anesthetic by retrospective analysis of data of patients who underwent major upper abdominal surgery under ultrasound-assisted thoracic epidural analgesia between July 2018 and October 2020. The primary outcome was total opioid consumption up to 72 h after surgery. The data of postoperative pain scores, epidural local anesthetic consumption, and adverse events from 193 patients were analyzed (continuous epidural infusion: n = 124, programmed intermittent epidural bolus: n = 69). There was no significant difference in the rescue opioid consumption in the 72 h postoperative period between the groups (33.3 mg [20.0-43.3] vs. 28.3 mg [18.3-43.3], p = 0.375). There were also no significant differences in the pain scores, epidural local anesthetic consumption, and incidence of adverse events. Our findings suggest that the quality of postoperative analgesia and safety following major upper abdominal surgery were comparable between the groups. However, the use of programmed intermittent epidural bolus requires further evaluation.

Real-time ultrasound-guided low thoracic epidural catheter placement: technical consideration and fluoroscopic evaluation.

BACKGROUND AND OBJECTIVE: Thoracic epidural analgesia can significantly reduce acute postoperative pain. However, thoracic epidural catheter placement is challenging. Although real-time ultrasound (US)-guided thoracic epidural catheter placement has been recently introduced, data regarding the accuracy and technical description are limited. Therefore, this prospective observational study aimed to assess the success rate and describe the technical considerations of real-time US-guided low thoracic epidural catheter placement. METHODS: 38 patients in the prone position were prospectively studied. After the target interlaminar space between T9 and T12 was identified, the needle was advanced under real-time US guidance and was stopped just short of the posterior complex. Further advancement of the needle was accomplished without US guidance using loss-of-resistance techniques to normal saline until the epidural space was accessed. Procedure-related variables such as time to mark space, needling time, number of needle passes, number of skin punctures, and the first-pass success rate were measured. The primary outcome was the success rate of real-time US-guided thoracic epidural catheter placement, which was evaluated using fluoroscopy. In addition, the position of the catheter, contrast dispersion, and complications were evaluated. RESULTS: This study included 38 patients. The T10-T11 interlaminar space was the most location for epidural access. During the procedure, the mean time for marking the overlying skin for the procedure was 49.5±13.8 s and the median needling time was 49 s. The median number of needle passes was 1.0 (1.0-1.0). All patients underwent one skin puncture for the procedure. The first-pass and second-pass success rates were 76.3% and 18.4%, respectively. Fluoroscopic evaluation revealed that the catheter tips were all positioned in the epidural space and were usually located between T9 and T10 (84.2%). The cranial and caudal contrast dispersion were observed up to 5.4±1.6 and 2.6±1.0 vertebral body levels, respectively. No procedure-related complications occurred. CONCLUSION: Real-time US guidance appears to be a feasible option for facilitating thoracic epidural insertion. Whether or not this technique improves the procedural success and quality compared with landmark-based techniques will require additional study. TRIAL REGISTRATION NUMBER: NCT03890640.

Continuous peritransplant assessment of consciousness using bispectral index monitoring for patients with fulminant hepatic failure undergoing urgent liver transplantation.

BACKGROUND: Rapid deterioration of consciousness is a critical situation for patients with fulminant hepatic failure (FHF). Bispectral (BIS) index was derived from electroencephalography parameters, primarily to monitor the depth of unconsciousness. AIM: To assess the usability of peritransplant BIS monitoring in patients with FHF. METHODS: A prospective study using peritransplant BIS monitoring was performed in 26 patients with FHF undergoing urgent liver transplantation (LT). RESULTS: Pre-transplant Child-Pugh score was 12.2 +/- 1.0; model for end-stage liver disease score was 32.4 +/- 4.4; Glasgow coma score (GCS) was 9.9 +/- 1.3; and BIS index was 44.0 +/- 6.7. Pre-transplant sedation significantly decreased BIS index. After LT, all patients having endotracheal intubation recovered consciousness within one to three d and showed progressive increase in BIS index, which appeared slightly earlier and was more evident than the increase in derived GCS score. There was a significant correlation between BIS index and derived GCS scores (r(2) = 0.648). Timing of eye opening to voice was matched with BIS index of 66.3 +/- 10.4 and occurred 12.7 +/- 8.3 h after passing BIS index of 50. CONCLUSION: These results suggest that BIS monitoring is a non-invasive, simple, easy-to-interpret method, which is useful in assessing peritransplant state of consciousness. BIS monitoring may therefore be a useful tool during peritransplant intensive care for patients with FHF showing hepatic encephalopathy.

Does Erector Spinae Plane Block Have a Visceral Analgesic Effect?: A Randomized Controlled Trial.

The visceral analgesic efficacy of erector spinae plane block (ESPB) is still a matter of debate. This study attempted to investigate the visceral analgesic efficacy of ESPB in clinical setting. After randomized, we performed ultrasound-guided bilateral rectus sheath block (RSB), which was aimed to prevent postoperative somatic pain on all patients who underwent laparoscopic cholecystectomy (LC). Ultrasound-guided bilateral ESPB at T7 level was performed only to the intervention group to provide the visceral analgesic block. The intraoperative requirement for remifentanil (P = 0.021) and the cumulative fentanyl consumption at postoperative 24-hours was significantly lower in the ESPB group (206.5 ± 82.8 µg vs.283.7 ± 102.4 µg, respectively; P = 0.004) compared to non-ESPB group. The ESPB group consistently showed lower accumulated analgesic consumption compared with those in the non-ESPB group at all observed time-points (all P < 0.05) after 2 hours and the degree of the accumulated analgesic consumption reduction was greater (P = 0.04) during the 24-hour postoperative period. Pain severity was lower in the ESPB group at 6-hours postoperatively. The significantly reduced opioid consumption in ESPB group may imply that while preliminary and in need of confirmation, ESPB has potential visceral analgesic effect. Therefore, performing ESPB solely may be feasible in inducing both somatic and visceral analgesia.

Preoperative versus Postoperative Rectus Sheath Block for Acute Postoperative Pain Relief after Laparoscopic Cholecystectomy: A Randomized Controlled Study.

BACKGROUND: Pain after laparoscopic cholecystectomy (LC) is multifactorial and usually not effectively treated. Rectus sheath block (RSB) has been proven to reduce the pain from midline abdominal incision and laparoscopic surgery. We investigated the preemptive analgesic effect of RSB after LC. METHODS: In this prospective, randomized, single-center trial, 200 patients undergoing LC were randomized into preoperative RSB (pre-RSB) or postoperative RSB (post-RSB) group. An ultrasound-guided RSB was performed before skin incision in the pre-RSB group or after skin closure in the post-RSB group. The primary outcome was total rescue analgesic consumption at 24 h post-surgery. The secondary outcomes were cumulated rescue analgesic consumption and postoperative pain measured by numerical rating scale (NRS) at 0, 1, 2, 6, 9, 18, and 24 h post-surgery. RESULTS: Total rescue analgesic consumption at 24 h post-surgery was significantly lower in the pre-RSB group than in the post-RSB group (p = 0.020). The cumulated rescue analgesic consumption was significantly lower in the pre-RSB group than in the post-RSB group at 1 h (p = 0.023), 9 h (p = 0.020) and 18 h (p = 0.002) post-surgery. NRS was significantly lower in the pre-RSB group than in the post-RSB group at 0 h post-surgery (p = 0.023). CONCLUSION: The pre-RSB reduced the analgesic requirements in patients undergoing LC compared with the post-RSB.

Warming of intravenous fluids prevents hypothermia during off-pump coronary artery bypass graft surgery.

OBJECTIVE: Even mild perioperative hypothermia (34 degrees -36 degrees C) can cause numerous adverse outcomes, including morbid cardiac events, coagulopathy with increased blood loss, and a decreased resistance to surgical wound infection. The purpose of this study was to evaluate the effect of fluid warming on preventing hypothermia during off-pump coronary artery bypass (OPCAB) surgery. DESIGN: A prospective randomized clinical study. SETTING: A tertiary care university hospital. PARTICIPANTS: Forty patients undergoing OPCAB procedures. INTERVENTIONS: Patients were randomized into control (n = 20) and Hotline (n = 20) groups. In the Hotline group, all intravenous fluids were warmed to 41 degrees C by using 2 Hotline (SIMS Inc, Rockland, MD) systems. All patients (control and Hotline groups) were managed with standardized institutional practice by using a combination of increased ambient operating room temperature (to 25 degrees C) and the use of a warmed water mattress (38 degrees C). MEASUREMENTS AND MAIN RESULTS: Temperatures were recorded every hour after the induction of anesthesia at the pulmonary artery, nasopharynx, rectum, and bladder. In the Hotline group, temperatures were maintained or increased. In the control group, temperatures gradually decreased. There were no significant differences between the 2 groups in hemodynamic parameters, serum catecholamine concentrations, duration of intensive care unit stay, or duration of ward stay. CONCLUSIONS: The results show that the warming of intravenous fluids by using the Hotline system prevents decreases in systemic temperatures during OPCAB surgery.

Efficacy of Pectoral Nerve Block Type II for Breast-Conserving Surgery and Sentinel Lymph Node Biopsy: A Prospective Randomized Controlled Study.

Objectives: The pectoral nerve block type II (PECS II block) is widely used for postoperative analgesia after breast surgery. This study evaluated the analgesic efficacy of PECS II block in patients undergoing breast-conserving surgery (BCS) and sentinel lymph node biopsy (SNB). Methods: Patients were randomized to the control group (n=40) and the PECS II group (n=40). An ultrasound-guided PECS II block was performed after induction of anesthesia. The primary outcome measure was opioid consumption, and the secondary outcome was pain at the breast and axillary measured using the Numerical Rating Scale (NRS) 24 hours after surgery. Opioid requirement was assessed according to tumor location. Results: Opioid requirement was lower in the PECS II than in the control group (43.8 ± 28.5 µg versus 77.0 ± 41.9 µg, p < 0.001). However, the frequency of rescue analgesics did not differ between these groups. Opioid consumption in the PECS II group was significantly lower in patients with tumors in the outer area than that in patients with tumors in the inner area (32.5 ± 23.0 µg versus 58.0 ± 29.3 µg, p=0.007). The axillary NRS was consistently lower through 24 hr in the PECS II group. Conclusion: Although the PECS II block seemed to reduce pain intensity and opioid requirements for 24 h after BCS and SNB, these reductions may not be clinically significant. This trial is registered with Clinical Research Information Service KCT0002509.

Risk factors and outcomes associated with a higher use of inotropes in kidney transplant recipients.

Preservation of adequate perfusion pressures to the graft is a main focus of intraoperative management during kidney transplantation. We undertook this study to investigate the incidence of the higher use of inotropes in kidney transplant recipients and identify the patient outcomes and preoperative and intraoperative variables related to this.We retrospectively analyzed 1053 patients who underwent kidney transplantation at Asan Medical Center between January 2006 and February 2012, stratified by their inotropic score ([dopamine] + [dobutamine] + [epinephrine × 100] + [norepinephrine × 100]) <7 versus ≥7, wherein all doses are expressed as µg/kg/min. We evaluated preoperative characteristics, hemodynamic parameters, and intraoperative variables as well as postoperative outcomes, such as length of hospital stay and 1-year rejection and mortality rate.Receiver-operating characteristic analysis was performed to determine inotropic score to predict 1-year mortality. An inotropic score of 7 had the best combined sensitivity and specificity. An inotropic score ≥7 (137 patients, 13.0%) was significantly more prevalent in older patients, those with polycystic kidney disease, and at a 2nd transplant. Anesthesia time, the amounts of crystalloid and 5% albumin infused, and the need for red blood cell transfusion were significantly higher in the inotropic score ≥7 group. The patients with a higher use of inotropes required longer postoperative hospital stay and experienced a >2-fold higher rejection within the 1st year and a 4-fold higher 1-year mortality rate.A higher use of inotropes in kidney transplant recipients is more prevalent in older patients, those with a 2nd transplant and in patients with polycystic kidney disease as their primary renal disease. The postoperative hospital stay, rejection within the 1st year, and 1-year mortality rate are increased in patients with an inotropic score ≥7.

Lack of correlation between cerebral vasomotor reactivity and dynamic cerebral autoregulation during stepwise increases in inspired CO2 concentration.

Cerebral vasomotor reactivity (CVMR) and dynamic cerebral autoregulation (CA) are measured extensively in clinical and research studies. However, the relationship between these measurements of cerebrovascular function is not well understood. In this study, we measured changes in cerebral blood flow velocity (CBFV) and arterial blood pressure (BP) in response to stepwise increases in inspired CO2 concentrations of 3 and 6% to assess CVMR and dynamic CA in 13 healthy young adults [2 women, 32 ± 9 (SD) yr]. CVMR was assessed as percentage changes in CBFV (CVMRCBFV) or cerebrovascular conductance index (CVCi, CVMRCVCi) in response to hypercapnia. Dynamic CA was estimated by performing transfer function analysis between spontaneous oscillations in BP and CBFV. Steady-state CBFV and CVCi both increased exponentially during hypercapnia; CVMRCBFV and CVMRCVCi were greater at 6% (3.85 ± 0.90 and 2.45 ± 0.79%/mmHg) than at 3% CO2 (2.09 ± 1.47 and 0.21 ± 1.56%/mmHg, P = 0.009 and 0.005, respectively). Furthermore, CVMRCBFV was greater than CVMRCVCi during either 3 or 6% CO2 (P = 0.017 and P < 0.001, respectively). Transfer function gain and coherence increased in the very low frequency range (0.02-0.07 Hz), and phase decreased in the low-frequency range (0.07-0.20 Hz) when breathing 6%, but not 3% CO2 There were no correlations between the measurements of CVMR and dynamic CA. These findings demonstrated influences of inspired CO2 concentrations on assessment of CVMR and dynamic CA. The lack of correlation between CVMR and dynamic CA suggests that cerebrovascular responses to changes in arterial CO2 and BP are mediated by distinct regulatory mechanisms.

Postreperfusion syndrome during liver transplantation.

As surgical and graft preservation techniques have improved and immunosuppressive drugs have advanced, liver transplantation (LT) is now considered the gold standard for treating patients with end-stage liver disease worldwide. However, despite the improved survival following LT, severe hemodynamic disturbances during LT remain a serious issue for the anesthesiologist. The greatest hemodynamic disturbance is postreperfusion syndrome (PRS), which occurs at reperfusion of the donated liver after unclamping of the portal vein. PRS is characterized by marked decreases in mean arterial pressure and systemic vascular resistance, and moderate increases in pulmonary arterial pressure and central venous pressure. The underlying pathophysiological mechanisms of PRS are complex. Moreover, risk factors associated with PRS are not fully understood. Rapid and appropriate treatment with vasopressors, volume replacement, or venesection must be provided depending on the cause of the hemodynamic disturbance when hemodynamic instability becomes profound after reperfusion. The negative effects of PRS on postoperative early morbidity and mortality are clear, but the effect of PRS on postoperative long-term mortality remains a matter of debate.