Thoracolumbar interfascial plane (TLIP) block: a pilot study in volunteers.

PURPOSE: Regional anesthesia has been shown to improve outcomes in several recent studies. The transversus abdominis plane (TAP) block provides anesthesia to the abdominal wall by introducing local anesthetic to the ventral rami of the thoracolumbar nerves. This work quantifies the area of anesthesia obtained after performing the novel thoracolumbar interfascial plane block (analogous to the TAP block but intended for the back) which targets the sensory component of the dorsal rami of the thoracolumbar nerves. METHODS: Ten participants underwent bilateral ultrasound-guided injections of 0.2% ropivacaine 20 mL into the fascial plane between the multifidus and longissimus muscles. After five and 20 min, respectively, the area of anesthesia was plotted on the participant's back. Anesthesia was defined as loss of point discrimination to pinprick. RESULTS: Participants reported a mean (SD) area of anesthesia surrounding the needle injection site of 137.4 (71.0) cm(2) and 217.0 (84.7) cm(2) at five and 20 min after injection, respectively. The mean (SD) cephalad and caudal spread of local anesthetic from the site of injection was 6.5 (1.8) cm and 3.9 (1.2) cm, respectively. There were no complications or adverse events reported. CONCLUSION: This report shows that a reproducible area of anesthesia can be obtained by ultrasound-guided injection of local anesthetic in the fascial plane between the multifidus and longissimus muscles of the thoracolumbar spine. The area of anesthesia consistently covered the midline and had a predictable spread. This project was registered with clinicaltrials.gov (NCT02297191).

Prefrontal versus motor cortex transcranial direct current stimulation (tDCS) effects on post-surgical opioid use.

BACKGROUND: Pain is often a complaint that precedes total knee arthroplasty (TKA), however the procedure itself is associated with considerable post-operative pain lasting days to weeks which can predict longer-term surgical outcomes. Previously, we reported significant opioid-sparing effects of motor cortex transcranial direct current stimulation from a single-blind trial. In the present study, we used double-blind methodology to compare motor cortex tDCS and prefrontal cortex tDCS to both sham and active-control (active electrodes over non-pain modulating brain areas) tDCS. METHODS: 58 patients undergoing unilateral TKA were randomly assigned to receive 4 20-min sessions (a total of 80 min) of tDCS (2 mA) post-surgery with electrodes placed to create 4 groups: 1) MOTOR (n = 14); anode-motor/cathode-right prefrontal, 2) PREFRONTAL (n = 16); anode-left-prefrontal/cathode-right-sensory, 3) ACTIVE-CONTROL (n = 15); anode-left-temporal-occipital junction/cathode-medial-anterior-premotor-area, and 4) SHAM (n = 13); 0 mA-current stimulation using placements 1 or 2. Patient controlled analgesia (PCA; hydromorphone) use was tracked during the ∼72-h post-surgery. RESULTS: Patients in the sham group and the active-control group used 15.4 mg (SD = 14.1) and 16.0 mg (SD = 9.7) of PCA hydromorphone respectively. There was no difference between the slopes of the cumulative PCA usage curves between these two groups (p = 0.25; ns). Patients in the prefrontal tDCS group used an average of 11.7 mg (SD = 5.0) of PCA hydromporhone, and the slope of the cumulative PCA usage curve was significantly lower than sham (p < 0.0001). However, patients in the motor tDCS group used an average of 19.6 mg (SD = 11.9) hydromorphone and the slope of the PCA use curve was significantly higher than sham (p < 0.0001). CONCLUSIONS: Results from this double-blind cortical-target-optimization study suggest that anodal transcranial direct current stimulation (tDCS) over the left prefrontal cortex may be a reasonable approach to reducing post-TKA opioid requirements. Given the unexpected finding that motor cortex failed to produce an opioid sparing effect in this follow-up trial, further research in the area of post-operative cortical stimulation is still needed.

Pediatric arteriovenous extracorporeal membrane oxygenation (ECMO) as a bridge to cardiac transplantation.

BACKGROUND: Since 1990, extracorporeal membrane oxygenation (ECMO) has been used as a bridge to cardiac transplantation in 47 patients. METHODS: A review of the ECMO database, approved by the Arkansas Children's Hospital institutional review board, forms the basis of this report. We made statistical comparison using Fisher's exact probability testing. The ECMO circuitry was a roller occlusion pump with computer-assisted perfusion system technology. RESULTS: Thirty-two (68%) patients underwent transcatheter septostomy for cardiac decompression. Diagnosis at presentation was either congenital heart disease (CHD, n = 15) or cardiomyopathy (n = 32). Ages ranged from 1 day to 22 years old (median, 18 months old), and weight ranged from 2.9 to 100 kg (median, 10 kg). The average duration of support was 242 hours (range, 22-1078 hours). Overall long-term survival was 47%, with 16 (34%) patients successfully bridged to cardiac transplantation (of which 9 [56%] survived) and 13 (28%) successfully weaned from ECMO. Patients undergoing ECMO after cardiotomy had 31% survival. Survival was improved significantly (p < 0.02) in patients with cardiomyopathy (59%) vs those with CHD (20%). Patients with cardiomyopathy underwent 8 transplantations with 7 survivors (88%), whereas in the CHD group, there were 8 transplantations with only 2 survivors (25%), p < 0.05. Sub-analysis of the cardiomyopathy group revealed that patients with acute cardiomyopathy in association with documented viral illness had a 75% chance of being weaned from ECMO without undergoing transplantation. Complications during ECMO occurred in 45% of survivors and were more frequent in non-survivors. Infectious complications were most frequent, followed by neurologic complications, technical ECMO problems, and renal insufficiency. CONCLUSIONS: Patients with cardiomyopathy has a better prognosis than did those with CHD when using ECMO as a bridge to transplantation or survival. Complications are significant and increase with the duration of support. Extracorporeal membrane oxygenation for salvage and subsequent transplantation in this high-risk group of patients requires critical review. Alternative support options must be developed in the pediatric population that will allow improved outcomes, comparable with outcomes achieved in the adult population.

The extracardiac Fontan procedure without cardiopulmonary bypass: technique and intermediate-term results.

BACKGROUND: The extracardiac Fontan procedure (ECF) usually requires cardiopulmonary bypass (CPB). In this report, the results and techniques of this procedure without CPB at a single institution are presented. METHODS: Between August 1992 and December 2001, ECF without CPB was achieved in 24 of 44 patients undergoing an ECF. Mean age at surgery was 5.9 +/- 2.9 years, and mean weight was 20.7 +/- 12.6 kg. Diagnoses were tricuspid atresia in 9 patients, single-ventricle with pulmonary outflow tract obstruction in 7, pulmonary atresia/intact septum in 5, and other complex single-ventricle physiology in 3. Initial palliation was by arterial to pulmonary artery shunt in 21 and pulmonary artery banding in 1. A bidirectional cavopulmonary connection was created in 23 patients. A temporary inferior vena caval-to-atrial shunt was used to complete the procedure without CPB. Median graft size was 16 mm (range 14 to 20 mm). RESULTS: There was no early mortality, and 68% of patients were discharged without complications. Complications included persistent cyanosis in 4 patients, persistent pleural effusions in 2 (one chylous), and phrenic nerve injury in 1. Median postoperative hospital stay was 16 days (range 10 to 50) days. At a mean follow-up of 44 +/- 28 months, there was no conduit obstruction. One patient died 11 months postoperatively, and 1 patient received a heart transplant 26 months post-ECF. CONCLUSIONS: At intermediate term follow-up, the ECF without CPB appears to be safe and technically reproducible in selected cases. Ongoing follow-up of these patients is necessary to document the theoretical advantages of avoiding CPB.

Transcranial direct current stimulation (tDCS) reduces postsurgical opioid consumption in total knee arthroplasty (TKA).

BACKGROUND: Although pain is often a symptom that precedes total knee arthroplasty (TKA), the procedure itself is associated with considerable postoperative pain lasting days to weeks. Postoperative pain control is an important factor in determining recovery time, hospital length of stay, and rehabilitation success. Several brain stimulation technologies including transcranial direct current stimulation (tDCS) have demonstrated promise as treatments for a variety of pain conditions. The present study examined the effects of 4 sessions of tDCS on post-TKA pain and opioid consumption. MATERIALS AND METHODS: Forty patients undergoing unilateral TKA were randomly assigned to receive a total of 80 minutes of real (n=20) or sham tDCS (n=20) with the anode over the knee representation of the motor strip (C1h or C2h corresponding to the target knee) and cathode over the right dorsolateral prefrontal cortex (F3; located by the EEG 10-20 System). Patient-controlled analgesia ( hydromorphone) use was tracked during the ∼48 hours postsurgery. RESULTS: Patients in the real tDCS group used an average of 6.6 mg (SD=5.3) of patient-controlled analgesia hydromorphone, whereas those in the sham group used 12.3 mg (SD=6.6; t37=2.93, P=0.006). Despite using less opioid medication, participants in the real tDCS group reported no pain exacerbation or worse mood with respect to those in the sham tDCS group. CONCLUSIONS: Results from this pilot feasibility study suggest that tDCS may be able to reduce post-TKA opioid requirements. Although these results are preliminary, the data support further research in the area of adjunctive cortical stimulation in the management of postsurgical pain.