Endovascular Occlusion of Giant Posttraumatic Pseudo-Aneurysm of Superior Mesenteric Artery Connected to Mesenteric Arteriovenous Fistula

The aim of the study was to show the capabilities of endovascular occlusion of giant posttraumatic pseudo-aneurysm of superior mesenteric artery (SMA) connected to a mesenteric arteriovenous fistula (AVF) under the conditions of portal hypertension and life-threatening esophageal variceal bleeding.

[Diagnosis and surgical treatment of symptomic stomach diverticulum]

Gastric diverticulum is a rather rare disease. This lesion is diagnosed in about 0.01% of cases during contrast-enhanced X-ray examination and in 0.04-0.11% of patients undergoing endoscopic examination. Symptomatic diverticulum is complicated by diverticulitis, bleeding, perforation and malignant transformation. Therefore, surgical resection is indicated. We report surgical treatment of a patient with diverticulum of the cardiac part of the stomach. Endoscopic and X-ray examination was valuable to establish the correct diagnosis. Laparoscopic approach minimized surgical trauma and reduced surgery time.

A Multidisciplinary Patient-Specific Opioid Prescribing and Tapering Protocol Is Associated with a Decrease in Total Opioid Dose Prescribed for Six Weeks After Total Hip Arthroplasty

Objective

This retrospective cohort study tested the hypothesis that implementing a multidisciplinary patient-specific discharge protocol for prescribing and tapering opioids after total hip arthroplasty (THA) will decrease the morphine milligram equivalent (MME) dose of opioids prescribed.

Methods

With institutional review board approval, we analyzed a Perioperative Surgical Home database and prescription data for all primary THA patients three months before (PRE) and three months after (POST) implementation of this new discharge opioid protocol based on patients’ prior 24-hour inpatient opioid consumption. The primary outcome was total opioid dosage in MME prescribed and opioid refills for six weeks after surgery. Secondary outcomes included the number of tablets and MME prescribed at discharge, in-hospital opioid consumption, length of stay, and postoperative complications.

Results

Forty-nine cases (25 PRE and 24 POST) were included. Total median (10th–90th percentiles) MME for six weeks postoperatively was 900 (57–2082) MME PRE vs 295 (69–741) MME POST (mean difference = 721, 95% confidence interval [CI] = 127–1316, P = 0.007, Mann-Whitney U test). Refill rates did not differ. The median (10th–90th percentiles) initial discharge prescription in MME was 675 (57–1035) PRE vs 180 (18–534) POST (mean difference = 387, 95% CI = 156–618, P = 0.003, Mann-Whitney U test) MME. There were no differences in other outcomes.

Conclusions

Implementation of a patient-specific prescribing and tapering protocol decreases the mean six-week dosage of opioid prescribed by 63% after THA without increasing the refill rate.

Outcomes of Ambulatory Upper Extremity Surgery Patients Discharged Home with Perineural Catheters from a Veterans Health Administration Medical Center

Objective

The feasibility and safety of managing ambulatory continuous peripheral nerve blocks (CPNB) in Veterans Health Administration (VHA) patients are currently unknown. We aimed to characterize the outcomes of a large VHA cohort of ambulatory upper extremity surgery patients discharged with CPNB and identify differences, if any, between catheter types.

Methods

With institutional review board approval, we reviewed data for consecutive patients from a single VHA hospital who had received ambulatory CPNB for upper extremity surgery from March 2011 to May 2017. The composite primary outcome was the occurrence of any catheter-related issue or additional all-cause health care intervention after discharge. Our secondary outcome was the ability to achieve regular daily telephone contact.

Results

Five hundred one patients formed the final sample. The incidence of any issue or health care intervention was 104/274 (38%) for infraclavicular, 58/185 (31%) for interscalene, and 14/42 (33%) for supraclavicular; these rates did not differ between groups. Higher ASA status was associated with greater odds of having any issue, whereas increasing age was slightly protective. Distance was associated with an increase in catheter-related issues (P < 0.01) but not additional health care interventions (P = 0.51). Only interscalene catheter patients (3%) reported breathing difficulty. Infraclavicular catheter patients had the most emergency room visits but rarely for CPNB issues. Consistent daily telephone contact was not achieved.

Conclusions

For VHA ambulatory CPNB patients, the combined incidence of a catheter-related issue or additional health care intervention was approximately one in three patients and did not differ by brachial plexus catheter type. Serious adverse events were generally uncommon.

Implementation of the IPACK (Infiltration between the Popliteal Artery and Capsule of the Knee) block into a multimodal analgesic pathway for total knee replacement

Background

The Infiltration between the Popliteal Artery and Capsule of the Knee (IPACK) block is a new anesthesiologist- administered analgesic technique for controlling posterior knee pain that has not yet been well studied in total knee arthroplasty (TKA) patients. We compared pain outcomes in TKA patients before and after implementation of the IPACK with the hypothesis that patients receiving IPACK blocks will report lower pain scores on postoperative day (POD) 0 than non-IPACK patients.

Methods

With Institutional Review Board approval, we retrospectively reviewed data for consecutive TKA patients by a single surgeon 4 months before (PRE) and after (POST) IPACK implementation. All TKA patients received adductor canal catheters and peri-operative multimodal analgesia. The primary outcome was pain on POD 0. Other outcomes were daily pain scores, opioid consumption, ambulation distance, length of stay, and adverse events within 30 days.

Results

Post-implementation, 48/50 (96%) of TKA patients received an IPACK block, and they were compared with 32 patients in the PRE group. On POD 0, the lowest pain score (median [10th–90th percentiles]) was significantly lower for the POST group compared to the PRE group (0 [0–4.3] vs. 2.5 [0–7]; P = 0.003). The highest patient-reported pain scores on any POD were similar between groups with no differences in other outcomes.

Conclusions

Within a multimodal analgesic protocol, addition of IPACK blocks decreased the lowest pain scores on POD 0. Although other outcomes were unchanged, there may be a role for new opioid-sparing analgesic techniques, and changing clinical practice change can occur rapidly.

Patient education and engagement in postoperative pain management decreases opioid use following knee replacement surgery

OBJECTIVE

Effects of patient education on perioperative analgesic utilization are not well defined. We designed a simple pain management educational card for total knee arthroplasty (TKA) patients and retrospectively reviewed clinical data before and after implementation to test the hypothesis that more informed patients will use less opioid.

METHODS

With IRB approval, we analyzed clinical data collected perioperatively on all TKA patients one month before (PRE) and one month after (POST) card implementation. The card was designed using a modified Delphi method; the front explained all analgesic medications and the Defense and Veterans Pain Rating Scale was on the back. The primary outcome was total opioid dosage in morphine milligram equivalents (MME) for the first two postoperative days. Secondary outcomes included daily opioid usage, pain scores, ambulation distance, hospital length of stay and use of antiemetics.

RESULTS

There were 20 patients in each group with no differences in baseline characteristics. Total two-day MME [median (10th-90th percentiles)] was 71 (32-285) for PRE and 38 (1-117) for POST (p = 0.001). There were no other differences.

CONCLUSION

Educating TKA patients in multimodal pain management using a simple tool decreases opioid usage.

PRACTICE IMPLICATIONS

Empowering TKA patients with education can reduce opioid use perioperatively.

Peripheral nerve blocks are not associated with increased risk of perioperative peripheral nerve injury in a Veterans Affairs inpatient surgical population

Background and objectives

Perioperative peripheral nerve injury (PNI) is a known complication in patients undergoing surgery with or without regional anesthesia. The incidence of new PNI in a Veterans Affairs (VA) inpatient surgical population has not been previously described; therefore, the incidence, risk factors, and clinical course of new PNI in this cohort are unknown. We hypothesized that peripheral nerve blocks do not increase PNI incidence.

Methods

We conducted a 5-year review of a Perioperative Surgical Home database including all consecutive surgical inpatients. The primary outcome was new PNI between groups that did or did not have peripheral nerve blockade. Potential confounders were first examined individually using logistic regression, and then included simultaneously together within a mixed-effects logistic regression model. Electronic records of patients with new PNI were reviewed for up to a year postoperatively.

Results

The incidence of new PNI was 1.2% (114/9558 cases); 30 of 3380 patients with nerve block experienced new PNI (0.9%) compared with 84 of 6178 non-block patients (1.4%; p=0.053). General anesthesia alone, younger age, and American Society of Anesthesiologists physical status <3 were associated with higher incidence of new PNI. Patients who received transversus abdominis plane blocks had increased odds for PNI (OR, 3.20, 95% CI 1.34 to 7.63), but these cases correlated with minimally invasive general and urologic surgery. One hundred PNI cases had 1-year follow-up: 82% resolved by 3 months and only one patient did not recover in a year.

Conclusions

The incidence of new perioperative PNI for VA surgical inpatients is 1.2% and the use of peripheral nerve blocks is not an independent risk factor.

Simulation-based ultrasound-guided regional anesthesia curriculum for anesthesiology residents

Proficiency in ultrasound-guided regional anesthesia (UGRA) requires the practitioner to acquire cognitive and technical skills. For anesthesiology residents, an assortment of challenges has been identified in learning UGRA skills. Currently, a validated UGRA curriculum for residents does not exist, and the level of UGRA proficiency achieved during residency training can vary considerably. Simulated practice has been shown to enhance proficiency in UGRA, and a competency-based education with simulation training has been endorsed for anesthesiology residents. The objective of this review is to outline simulation-based training that can be implemented in a UGRA curriculum and to explore educational tools like gamification to facilitate competency in regional anesthesiology.

Establishing an Acute Pain Service in Private Practice and Updates on Regional Anesthesia Billing

Acute pain management is an expanding perioperative specialty and there is a renewed focus on implementing and developing an acute pain service (APS) in nonacademic hospitals (ie, "private practice"). An anesthesiologist-led APS can improve patient care by decreasing perioperative morbidity and potentially reducing the risk of chronic postsurgical pain syndromes. Elements of a successful APS include multidisciplinary collaboration to develop perioperative pain protocols, education of health care providers and patients, and regular evaluation of patient safety and quality of care metrics. Standardization of regional anesthesia procedures and billing practices can promote consistent outcomes and efficiency.

Perioperative Surgical Home Reduces Rapid Response Calls to a Postoperative Surgical Ward: How Anesthesiologists Are Improving the Inpatient Safety Net

BACKGROUND

The Perioperative Surgical Home (PSH) is an anesthesiologist-led, coordinated care model that may improve patient experience and safety. We hypothesized that PSH will decrease activation of the rapid response system for surgical inpatients.

METHODS

This retrospective study was performed at an academic Veterans Affairs hospital with a PSH. Data from both medical and surgical cohorts admitted to a single ward were analyzed for the Pre-PSH (July 2006 to October 2010) and Post-PSH (November 2011 to May 2015) epochs. The primary outcome was incidence of rapid response team (RRT) activations per 1000 bed-days.

RESULTS

Surgical patients had 5.8 RRT activations per 1000 bed-days Pre-PSH versus 3.7/1000 bed-days Post-PSH ( P = .006). There was no difference in RRT activations per 1000 bed-days for medical patients before and after PSH implementation. Pre-PSH was an independent predictor of mortality in the multivariable model (odds ratio = 1.7; P = .010).

CONCLUSION

PSH is associated with decreased RRT activations among surgical inpatients only.

Preliminary Experience Using Eye-Tracking Technology to Differentiate Novice and Expert Image Interpretation for Ultrasound-Guided Regional Anesthesia

OBJECTIVES

Objective measures are needed to guide the novice's pathway to expertise. Within and outside medicine, eye tracking has been used for both training and assessment. We designed this study to test the hypothesis that eye tracking may differentiate novices from experts in static image interpretation for ultrasound (US)-guided regional anesthesia.

METHODS

We recruited novice anesthesiology residents and regional anesthesiology experts. Participants wore eye-tracking glasses, were shown 5 sonograms of US-guided regional anesthesia, and were asked a series of anatomy-based questions related to each image while their eye movements were recorded. The answer to each question was a location on the sonogram, defined as the area of interest (AOI). The primary outcome was the total gaze time in the AOI (seconds). Secondary outcomes were the total gaze time outside the AOI (seconds), total time to answer (seconds), and time to first fixation on the AOI (seconds).

RESULTS

Five novices and 5 experts completed the study. Although the gaze time (mean ± SD) in the AOI was not different between groups (7 ± 4 seconds for novices and 7 ± 3 seconds for experts; P = .150), the gaze time outside the AOI was greater for novices (75 ± 18 versus 44 ± 4 seconds for experts; P = .005). The total time to answer and total time to first fixation in the AOI were both shorter for experts.

CONCLUSIONS

Experts in US-guided regional anesthesia take less time to identify sonoanatomy and spend less unfocused time away from a target compared to novices. Eye tracking is a potentially useful tool to differentiate novices from experts in the domain of US image interpretation.

Virtual reality distraction decreases routine intravenous sedation and procedure-related pain during preoperative adductor canal catheter insertion: a retrospective study

Background

Virtual reality (VR) distraction is a nonpharmacological method to prevent acute pain that has not yet been thoroughly explored for anesthesiology. We present our experience using VR distraction to decrease routine intravenous sedation for patients undergoing preoperative perineural catheter insertion.

Methods

This 1-month quality improvement project involved all elective unilateral primary total knee arthroplasty patients who received a preoperative adductor canal catheter. Clinical data were analyzed retrospectively. For the first half of the month, all patients received usual care; intravenous sedation was administered at the discretion of the regional anesthesiologist. For the second half of the month, patients were offered VR distraction with intravenous sedation upon request. The primary outcome was fentanyl dosage; other outcomes included midazolam dosage, procedure-related pain, procedural time, and blood pressure changes.

Results

Seven patients received usual care and seven used VR. In the VR group, 1/7 received intravenous sedation versus 6/7 who received usual care (P = 0.029). The fentanyl dose was lower (median [10th–90th percentiles]) in the VR group (0 [0–20] µg) versus the non-VR group (50 [30–100] µg; P = 0.008). Midazolam use was lower in the VR group (0 [0–0] mg) than in the non-VR group (1 [0–1] mg; P = 0.024). Procedure-related pain was lower in the VR group (1 [1–4] NRS) versus the non-VR group (3 [2–6] NRS; P = 0.032). There was no difference in other outcomes.

Conclusions

VR distraction may provide an effective nonpharmacological alternative to intravenous sedation for the ultrasound-guided placement of certain perineural catheters.

Implementation of clinical practice changes by experienced anesthesiologists after simulation-based ultrasound-guided regional anesthesia training

Background

Anesthesiologists who have finished formal training and want to learn ultrasound-guided regional anesthesia (UGRA) commonly attend 1 day workshops. However, it is unclear whether participation actually changes clinical practice. We assessed change implementation after completion of a 1 day simulation-based UGRA workshop.

Methods

Practicing anesthesiologists who participated in a 1 day UGRA course from January 2012 through May 2014 were surveyed. The course consisted of clinical observation of UGRA procedures, didactic lectures, ultrasound scanning, hands-on perineural catheter placement, and mannequin simulation. The primary outcome was the average number of UGRA blocks per month reported at follow-up versus baseline. Secondary outcomes included preference for ultrasound as the nerve localization technique, ratings of UGRA teaching methods, and obstacles to performing UGRA.

Results

Survey data from 46 course participants (60% response rate) were included for analysis. Participants were (median [10th–90th percentile]) 50 (37–63) years old, had been in practice for 17 (5–30) years, and were surveyed 27 (10–34) months after their UGRA training. Participants reported performing 24 (4–90) blocks per month at follow-up compared to 10 (2–24) blocks at baseline (P < 0.001). Compared to baseline, more participants at follow-up preferred ultrasound for nerve localization. The major obstacle to implementing UGRA in clinical practice was time pressure.

Conclusions

Participation in a 1 day simulation-based UGRA course may increase UGRA procedural volume by practicing anesthesiologists.

Randomized comparison of popliteal-sciatic perineural catheter tip migration and dislocation in a cadaver model using two catheter designs

BACKGROUND

New catheter-over-needle (CON) technology for continuous peripheral nerve blockade has emerged, but its effect on the risk of perineural catheter tip dislocation is unknown. Less flexible catheters may be more likely to migrate away from the nerve with simulated patient movement. In the present study, we evaluated catheter tip migration between CON catheters and traditional catheter-through-needle (CTN) catheters during ultrasound-guided short-axis in-plane (SAX-IP) insertion.

METHODS

We evaluated the migration of popliteal-sciatic catheters in a prone, unembalmed male cadaver. Thirty catheter placement trials were divided randomly into two groups based on the catheter type: CON or CTN. A single anesthesiology resident placed the catheters by SAX-IP insertion, and the catheters were then examined by ultrasound before and after ipsilateral knee range of motion (ROM) exercises (0°-130° flexion). A blinded expert regional anesthesiologist performed caliper measurements on the ultrasound images before and after the ROM exercises. The primary outcome was the change in distance from the catheter tip to the center of the nerve (cm) between before and after the ROM exercises.

RESULTS

The change in the tip-to-nerve distance (median [10th-90th percentile]) was 0.06 (-0.16 to 0.23) cm for the CTN catheter and 0.00 (-0.12 to 0.69) for the CON catheter (P = 0.663). However, there was a statistically significant increase in dislocation out of the nerve compartment for the CON catheter (4/15; 0/15 for CTN) (P = 0.043).

CONCLUSIONS

Although the use of different catheter designs had no effect on the change in the measured migration distance of popliteal-sciatic catheters, 27% of the CON catheters were dislocated out of the nerve compartment. These results may influence the choice of catheter design when using SAX-IP perineural catheter insertion.

A comparison of strength for two continuous peripheral nerve block catheter dressings

BACKGROUND

Despite the benefits of continuous peripheral nerve blocks, catheter dislodgment remains a major problem, especially in the ambulatory setting. However, catheter dressing techniques to prevent such dislodgment have not been studied rigorously. We designed this simulation study to test the strength of two commercially available catheter dressings.

METHODS

Using a cadaver model, we randomly assigned 20 trials to one of two dressing techniques applied to the lateral thigh: 1) clear adhesive dressing alone, or 2) clear adhesive dressing with an anchoring device. Using a digital luggage scale attached to a loop secured by the dressing, the same investigator applied steadily increasing force with a downward trajectory towards the floor until the dressing was removed or otherwise disrupted.

RESULTS

The weight, measured (median [10th-90th percentile]) at the time of dressing disruption or removal, was 1.5 kg (1.3-1.8 kg) with no anchoring device versus 4.9 kg (3.7-6.5 kg) when the dressing included an anchoring device (P < 0.001).

CONCLUSIONS

Based on this simulation study, using an anchoring device may help prevent perineural catheter dislodgement and therefore premature disruption of continuous nerve block analgesia.

An ultrasound-guided fascia iliaca catheter technique does not impair ambulatory ability within a clinical pathway for total hip arthroplasty

Background

Both neuraxial and peripheral regional analgesic techniques offer postoperative analgesia for total hip arthroplasty (THA) patients. While no single technique is preferred, quadriceps muscle weakness from peripheral nerve blocks may impede rehabilitation. We designed this study to compare postoperative ambulation outcome in THA patients who were treated with a new ultrasound-guided fascia iliaca catheter (FIC) technique or intrathecal morphine (ITM).

Methods

We reviewed the electronic health records of a sequential series of primary unilateral THA patients who were part of a standardized clinical pathway; apart from differences in regional analgesic technique, all other aspects of the pathway were the same. Our primary outcome was total ambulation distance (meters) combined for postoperative days 1 and 2. Secondary outcomes included daily opioid consumption (morphine milligram equivalents) and analgesic-related side effects. We examined the association between the primary outcome and analgesic technique by performing crude and adjusted ordinary least-squares linear regression. A P value < 0.05 was considered statistically-significant.

Results

The study analyzed the records of 179 patients (fascia iliaca, n = 106; intrathecal, n = 73). The primary outcome (total ambulation distance) did not differ between the groups (P = 0.08). Body mass index (BMI) was the only factor (β = -1.7 [95% CI -0.5 to -2.9], P < 0.01) associated with ambulation distance. Opioid consumption did not differ, while increased pruritus was seen in the intrathecal group (P < 0.01).

Conclusions

BMI affects postoperative ambulation outcome after hip arthroplasty, whereas the type of regional analgesic technique used does not. An ultrasound-guided FIC technique offers similar analgesia with fewer side effects when compared with ITM.

Can bedside patient-reported numbness predict postoperative ambulation ability for total knee arthroplasty patients with nerve block catheters?

BACKGROUND

Adductor canal catheters offer advantages over femoral nerve catheters for knee replacement patients because they produce less quadriceps muscle weakness; however, applying adductor canal catheters in bedside clinical practice remains challenging. There is currently no patient-reported outcome that accurately predicts patients' physical function after knee replacement. The present study evaluates the validity of a relatively new patient-reported outcome, i.e., a numbness score obtained using a numeric rating scale, and assesses its predictive value on postoperative ambulation.

METHODS

We conducted a retrospective cohort study pooling data from two previously-published clinical trials using identical research methodologies. Both studies recruited patients undergoing knee replacement; one studied adductor canal catheters while the other studied femoral nerve catheters. Our primary outcome was patient-reported numbness scores on postoperative day 1. We also examined postoperative day 1 ambulation distance and its association with postoperative numbness using linear regression, adjusting for age, body mass index, and physical status.

RESULTS

Data from 94 subjects were included (femoral subjects, n = 46; adductor canal subjects, n = 48). Adductor canal patients reported decreased numbness (median [10(th)-90(th) percentiles]) compared to femoral patients (0 [0-5] vs. 4 [0-10], P = 0.001). Adductor canal patients also ambulated seven times further on postoperative day 1 relative to femoral patients. There was a significant association between postoperative day 1 total ambulation distance and numbness (Beta = -2.6; 95% CI: -4.5, -0.8, P = 0.01) with R(2) = 0.1.

CONCLUSIONS

Adductor canal catheters facilitate improved early ambulation and produce less patient-reported numbness after knee replacement, but the correlation between these two variables is weak.

Comparative Effectiveness of Two Ultrasound-Guided Regional Block Techniques for Surgical Anesthesia in Open Unilateral Inguinal Hernia Repair

Transversus abdominis plane (TAP) and ilioinguinal/iliohypogastric (II/IH) nerve blocks have been described as analgesic adjuncts for inguinal hernia repair, but the efficacy of these techniques in providing intraoperative anesthesia, either individually or together, is not known. We designed this retrospective cohort study to test the hypothesis that combining TAP and II/IH nerve blocks ("double TAP" technique) results in greater accordance between the preoperative anesthetic plan and actual anesthetic technique provided when compared to TAP alone. Based on this study, double TAP may be preferred for patients undergoing open inguinal hernia repair who wish to avoid general anesthesia.

Evaluation of a Standardized Program for Training Practicing Anesthesiologists in Ultrasound-Guided Regional Anesthesia Skills

OBJECTIVES

Practicing anesthesiologists have generally not received formal training in ultrasound-guided perineural catheter insertion. We designed this study to determine the efficacy of a standardized teaching program in this population.

METHODS

Anesthesiologists in practice for 10 years or more were recruited and enrolled to participate in a 1-day program: lectures and live-model ultrasound scanning (morning) and faculty-led iterative practice and mannequin-based simulation (afternoon). Participants were assessed and recorded while performing ultrasound-guided perineural catheter insertion at baseline, at midday (interval), and after the program (final). Videos were scored by 2 blinded reviewers using a composite tool and global rating scale. Participants were surveyed every 3 months for 1 year to report the number of procedures, efficacy of teaching methods, and implementation obstacles.

RESULTS

Thirty-two participants were enrolled and completed the program; 31 of 32 (97%) completed the 1-year follow-up. Final scores [median (10th-90th percentiles)] were 21.5 (14.5-28.0) of 30 points compared to 14.0 (9.0-20.0) at interval (P < .001 versus final) and 12.0 (8.5-17.5) at baseline (P < .001 versus final), with no difference between interval and baseline. The global rating scale showed an identical pattern. Twelve of 26 participants without previous experience performed at least 1 perineural catheter insertion after training (P < .001). However, there were no differences in the monthly average number of procedures or complications after the course when compared to baseline.

CONCLUSIONS

Practicing anesthesiologists without previous training in ultrasound-guided regional anesthesia can acquire perineural catheter insertion skills after a 1-day standardized course, but changing clinical practice remains a challenge.

Design and Implementation of a Perioperative Surgical Home at a Veterans Affairs Hospital

The innovative Perioperative Surgical Home model aims to optimize the outcomes of surgical patients by leveraging the expertise and leadership of physician anesthesiologists, but there is a paucity of practical examples to follow. Veterans Affairs health care, the largest integrated system in the United States, may be the ideal environment in which to explore this model. We present our experience implementing Perioperative Surgical Home at one tertiary care university-affiliated Veterans Affairs hospital. This process involved initiating consistent postoperative patient follow-up beyond the postanesthesia care unit, a focus on improving in-hospital acute pain management, creation of an accessible database to track outcomes, developing new clinical pathways, and recruiting additional staff. Today, our Perioperative Surgical Home facilitates communication between various services involved in the care of surgical patients, monitoring of patient outcomes, and continuous process improvement.

Simulation in teaching regional anesthesia: current perspectives

The emerging subspecialty of regional anesthesiology and acute pain medicine represents an opportunity to evaluate critically the current methods of teaching regional anesthesia techniques and the practice of acute pain medicine. To date, there have been a wide variety of simulation applications in this field, and efficacy has largely been assumed. However, a thorough review of the literature reveals that effective teaching strategies, including simulation, in regional anesthesiology and acute pain medicine are not established completely yet. Future research should be directed toward comparative-effectiveness of simulation versus other accepted teaching methods, exploring the combination of procedural training with realistic clinical scenarios, and the application of simulation-based teaching curricula to a wider range of learner, from the student to the practicing physician.

Comparative effectiveness of infraclavicular and supraclavicular perineural catheters for ultrasound-guided through-the-catheter bolus anesthesia

OBJECTIVES

Using a through-the-needle local anesthetic bolus technique, ultrasound-guided infraclavicular perineural catheters have been shown to provide greater analgesia compared to supraclavicular catheters. A through-the-catheter bolus technique, which arguably "tests" the anesthetic efficacy of the catheter before initiating an infusion, has been validated for infraclavicular catheters but not supraclavicular catheters. This study investigated the through-the-catheter bolus technique for supraclavicular catheters and tested the hypothesis that infraclavicular catheters provide faster onset of brachial plexus anesthesia.

METHODS

Preoperatively, patients were randomly assigned to receive either a supraclavicular or an infraclavicular catheter using an ultrasound-guided nonstimulating catheter insertion technique with a mepivacaine bolus via the catheter and ropivacaine perineural infusion initiated postoperatively. The primary outcome was time to achieve complete sensory anesthesia in the ulnar and median nerve distributions. Secondary outcomes included procedural time, procedure-related pain and complications, and postoperative pain, opioid consumption, sleep disturbances, and motor weakness.

RESULTS

Fifty patients were enrolled in the study; all but 2 perineural catheters were successfully placed per protocol. Twenty-one of 24 (88%) and 24 of 24 (100%) patients in the supraclavicular and infraclavicular groups, respectively, achieved complete sensory anesthesia by 30 minutes (P= .088). There was no difference in the time to achieve complete sensory anesthesia. Supraclavicular patients reported more sleep disturbances postoperatively, but there were no statistically significant differences in other outcomes.

CONCLUSIONS

Both supraclavicular and infraclavicular perineural catheters using a through-the-catheter bolus technique provide effective brachial plexus anesthesia.

Developing a multidisciplinary fall reduction program for lower-extremity joint arthroplasty patients

With the anticipated increase in the number of total joint arthroplasty surgeries and associated fall risks, a fall reduction program can provide greater safety for patients in the postoperative period. Although further prospective studies are needed among total joint arthroplasty patients, there is sufficient evidence to show that a successful fall reduction program can be implemented. Common components to date have included a multidisciplinary team, multicomponent interventions specific to the risks associated with total knee and hip arthroplasty patients, education of patients and staff, and strategies to promote adherence to the program.

A pilot in vitro evaluation of the "air test" for perineural catheter tip localization by a novice regional anesthesiologist

The "air test" is used clinically to infer perineural catheter location and has been recently evaluated for use by experts. However, its utility for practitioners with less experience is unknown. We tested the hypothesis that the air test, when performed by a novice regional anesthesiologist, will improve assessment of perineural catheter tip position in a validated porcine-bovine model and determined the test's positive and negative predictive values, sensitivity, and specificity for a novice. In contrast to the results of the expert study, the air test did not improve the novice's assessment of perineural catheter tip location over chance.

A randomized comparison of proximal and distal ultrasound-guided adductor canal catheter insertion sites for knee arthroplasty

OBJECTIVES

Proximal and distal (mid-thigh) ultrasound-guided continuous adductor canal block techniques have been described but not yet compared, and infusion benefits or side effects may be determined by catheter location. We hypothesized that proximal placement will result in faster onset of saphenous nerve anesthesia, without additional motor block, compared to a distal technique.

METHODS

Preoperatively, patients receiving an ultrasound-guided nonstimulating adductor canal catheter for knee arthroplasty were randomly assigned to either proximal or distal insertion. A local anesthetic bolus was administered via the catheter after successful placement. The primary outcome was the time to achieve complete sensory anesthesia in the saphenous nerve distribution. Secondary outcomes included procedural time, procedure-related pain and complications, postoperative pain, opioid consumption, and motor weakness.

RESULTS

Proximal insertion (n = 23) took a median (10th-90th percentiles) of 12.0 (3.0-21.0) minutes versus 6.0 (3.0-21.0) minutes for distal insertion (n = 21; P= .106) to anesthetize the medial calf. Only 10 of 25 (40%) and 10 of 24 (42%) patients in the proximal and distal groups, respectively, developed anesthesia at both the medial calf and top of the patella (P= .978). Bolus-induced motor weakness occurred in 19 of 25 (76%) and 16 of 24 (67%) patients in the proximal and distal groups (P = .529). Ten of 24 patients (42%) in the distal group required intravenous morphine postoperatively, compared to 2 of 24 (8%) in the proximal group (P = .008), but there were no differences in other secondary outcomes.

CONCLUSIONS

Continuous adductor canal blocks can be performed reliably at both proximal and distal locations. The proximal approach may offer minor analgesic and logistic advantages without an increase in motor block.

Continuous adductor canal blocks are superior to continuous femoral nerve blocks in promoting early ambulation after TKA

BACKGROUND

Femoral continuous peripheral nerve blocks (CPNBs) provide effective analgesia after TKA but have been associated with quadriceps weakness and delayed ambulation. A promising alternative is adductor canal CPNB that delivers a primarily sensory blockade; however, the differential effects of these two techniques on functional outcomes after TKA are not well established.

QUESTIONS/PURPOSES

We determined whether, after TKA, patients with adductor canal CPNB versus patients with femoral CPNB demonstrated (1) greater total ambulation distance on Postoperative Day (POD) 1 and 2 and (2) decreased daily opioid consumption, pain scores, and hospital length of stay.

METHODS

Between October 2011 and October 2012, 180 patients underwent primary TKA at our practice site, of whom 93% (n = 168) had CPNBs. In this sequential series, the first 102 patients had femoral CPNBs, and the next 66 had adductor canal CPNBs. The change resulted from a modification to our clinical pathway, which involved only a change to the block. An evaluator not involved in the patients' care reviewed their medical records to record the parameters noted above.

RESULTS

Ambulation distances were higher in the adductor canal group than in the femoral group on POD 1 (median [10(th)-90(th) percentiles]: 37 m [0-90 m] versus 6 m [0-51 m]; p < 0.001) and POD 2 (60 m [0-120 m] versus 21 m [0-78 m]; p = 0.003). Adjusted linear regression confirmed the association between adductor canal catheter use and ambulation distance on POD 1 (B = 23; 95% CI = 14-33; p < 0.001) and POD 2 (B = 19; 95% CI = 5-33; p = 0.008). Pain scores, daily opioid consumption, and hospital length of stay were similar between groups.

CONCLUSIONS

Adductor canal CPNB may promote greater early postoperative ambulation compared to femoral CPNB after TKA without a reduction in analgesia. Future randomized studies are needed to validate our major findings.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Application of echogenic technology for catheters used in ultrasound-guided continuous peripheral nerve blocks

Limited data exist regarding the echogenicity of perineural catheters, but visualization is crucial to ensure accurate placement and efficacy of the subsequent local anesthetic infusion. The objective of this study was to determine the comparative echogenicity of various regional anesthesia catheters. In an in vitro porcine-bovine model, we compared the echogenic qualities of 3 commercially available regional anesthesia catheters and 1 catheter under development to optimize echogenicity. Outcomes included visual echogenicity ranking, image quality, and scanning time, as assessed by 2 blinded investigators. The experimental catheter was found to be more echogenic than 2 of the 3 comparators.

An in vitro study to evaluate the utility of the "air test" to infer perineural catheter tip location

Injection of air under ultrasound guidance via a perineural catheter after insertion ("air test") has been described as a means to infer placement accuracy, yet this test has never been rigorously evaluated. We tested the hypothesis that the air test predicts accurate catheter location greater than chance and determined the test's sensitivity, specificity, and positive and negative predictive values using a porcine-bovine model and blinded expert in ultrasound-guided regional anesthesia. The air test improved the expert clinician's assessment of catheter tip position compared to chance, but there was no difference when compared to direct visualization of the catheter without air injection.

A randomized comparison of long-and short-axis imaging for in-plane ultrasound-guided femoral perineural catheter insertion

OBJECTIVES

Continuous femoral nerve blocks provide effective analgesia after knee arthroplasty, and infusion effects depend on reliable catheter location. Ultrasound-guided perineural catheter insertion using a short-axis in-plane technique has been validated, but the optimal catheter location relative to target nerve and placement orientation remain unknown. We hypothesized that a long-axis in-plane technique for femoral perineural catheter insertion results in faster onset of sensory anesthesia compared to a short-axis in-plane technique.

METHODS

Preoperatively, patients receiving an ultrasound-guided nonstimulating femoral perineural catheter for knee surgery were randomly assigned to either the long-axis in-plane or short-axis in-plane technique. A local anesthetic was administered via the catheter after successful insertion. The primary outcome was the time to achieve complete sensory anesthesia. Secondary outcomes included the procedural time, the onset time of the motor block, pain and muscle weakness reported on postoperative day 1, and procedure-related complications.

RESULTS

The short-axis group (n = 23) took a median (10th-90th percentiles) of 9.0 (6.0-20.4) minutes compared to 6.0 (3.0-14.4) minutes for the long-axis group (n = 23; P = .044) to achieve complete sensory anesthesia. Short-axis procedures took 5.0 (4.0-7.8) minutes to perform compared to 9.0 (7.0-14.8) minutes for long-axis procedures (P < .001). In the short-axis group, 19 of 23 (83%) achieved a complete motor block within the testing period compared to 18 of 23 (78%) in the long-axis group (P = .813); short-axis procedures took 12.0 (6.0-15.0) minutes versus 15.0 (5.1-27.9) minutes for long-axis procedures (P = .048). There were no statistically significant differences in other secondary outcomes.

CONCLUSIONS

Long-axis in-plane femoral perineural catheters result in a slightly faster onset of sensory anesthesia, but placement takes longer to perform without other clinical advantages.

Preliminary study of ergonomic behavior during simulated ultrasound-guided regional anesthesia using a head-mounted display

A head-mounted display provides continuous real-time imaging within the practitioner's visual field. We evaluated the feasibility of using head-mounted display technology to improve ergonomics in ultrasound-guided regional anesthesia in a simulated environment. Two anesthesiologists performed an equal number of ultrasound-guided popliteal-sciatic nerve blocks using the head-mounted display on a porcine hindquarter, and an independent observer assessed each practitioner's ergonomics (eg, head turning, arching, eye movements, and needle manipulation) and the overall block quality based on the injectate spread around the target nerve for each procedure. Both practitioners performed their procedures without directly viewing the ultrasound monitor, and neither practitioner showed poor ergonomic behavior. Head-mounted display technology may offer potential advantages during ultrasound-guided regional anesthesia.

Continuous femoral versus posterior lumbar plexus nerve blocks for analgesia after hip arthroplasty: a randomized, controlled study

BACKGROUND

Hip arthroplasty frequently requires potent postoperative analgesia, often provided with an epidural or posterior lumbar plexus local anesthetic infusion. However, American Society of Regional Anesthesia guidelines now recommend against epidural and continuous posterior lumbar plexus blocks during administration of various perioperative anticoagulants often administered after hip arthroplasty. A continuous femoral nerve block is a possible analgesic alternative, but whether it provides comparable analgesia to a continuous posterior lumbar plexus block after hip arthroplasty remains unclear. We therefore tested the hypothesis that differing the catheter insertion site (femoral versus posterior lumbar plexus) after hip arthroplasty has no impact on postoperative analgesia.

METHODS

Preoperatively, subjects undergoing hip arthroplasty were randomly assigned to receive either a femoral or a posterior lumbar plexus stimulating catheter inserted 5 to 15 cm or 0 to 1 cm past the needle tip, respectively. Postoperatively, patients received perineural ropivacaine, 0.2% (basal 6 mL/hr, bolus 4 mL, 30-minute lockout) for at least 2 days. The primary end point was the average daily pain scores as measured with a numeric rating scale (0-10) recorded in the 24-hour period beginning at 07:30 the morning after surgery, excluding twice-daily physical therapy sessions. Secondary end points included pain during physical therapy, ambulatory distance, and supplemental analgesic requirements during the same 24-hour period, as well as satisfaction with analgesia during hospitalization.

RESULTS

The mean (SD) pain scores for subjects receiving a femoral infusion (n = 25) were 3.6 (1.8) versus 3.5 (1.8) for patients receiving a posterior lumbar plexus infusion (n = 22), resulting in a group difference of 0.1 (95% confidence interval -0.9 to 1.2; P = 0.78). Because the confidence interval was within a prespecified -1.6 to 1.6 range, we conclude that the effect of the 2 analgesic techniques on postoperative pain was equivalent. Similarly, we detected no differences between the 2 treatments with respect to the secondary end points, with one exception: subjects with a femoral catheter ambulated a median (10th-90th percentiles) 2 (0-17) m the morning after surgery, in comparison with 11 (0-31) m for subjects with a posterior lumbar plexus catheter (data nonparametric; P = 0.02).

CONCLUSIONS

After hip arthroplasty, a continuous femoral nerve block is an acceptable analgesic alternative to a continuous posterior lumbar plexus block when using a stimulating perineural catheter. However, early ambulatory ability suffers with a femoral infusion.

Design parameters of high rate algal ponds using filamentous algae matrix for treating rural stream water

High rate algal ponds (HRAP) with a filamentous algae matrix (FAM) as the predominant species, were operated to evaluate the characteristics of FAM and the basic design parameters for treating polluted rural stream water. The porous and gelatinous FAM was formed like a sponge, which functions to prevent excessive loss of the algae in the effluent and can easily be retrieved from the ponds. The organic fraction of harvested FAM was about 88%, which is suitable for use as fertilizer. The HRAP system using FAM was found to be an effective nutrient removal process not requiring any artificial carbon sources for nitrification. At HRT 4 days, the T-N and T-P removal efficiencies were 85.9% and 65.8%, respectively. When the pH and water temperature were maintained above 9 and 15 degrees C, HRT required for achieving a 70% T-N removal efficiency could be reduced by about 3 days. The oxygen production rate by FAM was calculated as 1.45 mgO2/L/m2. The design surface area of HRAP needed per rural inhabitant was about 2.72 m2.

Determination and geographical distribution of Orientia tsutsugamushi serotypes in Korea by nested polymerase chain reaction

Field rodents and chigger mites were collected at 30 locations in Korea in October and November 1997-1999 to determine the serotypes of Orientia tsutsugamushi and their geographical distribution. A nested polymerase chain reaction was performed with the spleen tissues from 546 field-striped mice (Apodemus agrarius) and 104 pools of chigger mites. The positivity rate of O. tsutsugamushi was 45.6% in A. agrarius and 39.4% in the chigger mite pools. Two serotypes, Boryong and Karp, were found in these samples; the former was predominant (78.3% in the mice and 82.9% in the chigger mite pools), with wide distribution throughout the country, including Cheju-do. The latter was confined to the middle of the Korean peninsula, with positivity rates of 15.7% in the mice and 12.2% in the chigger mite pools. The double infection of Karp and Boryong serotypes was found in 15 (6.0%) A. agrarius mice. Gilliam serotype was not detected at any of the study locations. The Boryong and Kuroki serotypes were identical in amino acid sequence of the 56-kDa protein, although they differed in virulence to BALB/c mice.

Alterations of HLA class I and II antigen expression in preinvasive, invasive and metastatic cervical cancers

HLA expression is altered in a large variety of human cancers. We performed immunohistochemical staining on tissues from normal, preinvasive, invasive and metastatic cervical cancer tissues using anti-HLA class I or class II antibody. In tissues from normal squamous epithelium, carcinoma in situ (CIS) and microinvasive carcinoma (MIC), the expressions of HLA-B, C heavy chains and class II heavy chain were significantly decreased as disease progressed. When the expression patterns were compared between primary and metastatic squamous cell carcinoma (SCC) lesions, statistically significant down-regulation of HLA class I and class II antigen in metastatic lesions was observed. The rates of HLA-B, C heavy chains and class II heavy chain expressions were all significantly down-regulated compared to the down-regulation rate of class I beta2-microglobulin (beta2m) in invasive squamous lesions, and the expressions of class II heavy chain in metastatic lesions was decreased further than that in primary lesions. Unlike SCC, the degree of HLA class I and class II loss was not evident as disease progressed in early stage of adenocarcinoma. In invasive adenocarcinoma lesions, only the expression of HLA-B, C heavy chains was decreased and no differences were seen in HLA-B, C heavy chain expression patterns between primary and metastatic lesions. These results suggest that alterations of HLA class I and II expressions seem to occur at a particular step in cervical cancer development and depend on tissue types: when the tumor becomes invasive and starts to metastasize.

Protein kinase C modulates telomerase activity in human cervical cancer cells

Telomerase, a ribonucleoprotein reverse transcriptase that extends telomeres of eukaryotic chromosomes is repressed in normal somatic cells but is activated during development and neoplasia. The regulation mechanism of telomerase activity in cancer cells is not clearly known. In this report, a possible affect of PKC on telomerase activity was examined using HeLa and CUMC-6 cervical cancer cell lines. Exposure of cells to PKC inhibitor, bisindolylmaleimide I and Gö6976, and high levels of PKC activator, 12-O-tetradecanoyl phorbol 13-acetate (TPA) resulted in the inhibition of PKC activity in both cells. Telomerase activities were also inhibited by bisindolyl-maleimide I and Gö6976, respectively, in a time-dependent manner. As PKC activity changes in TPA-treated cervical cancer cells, telomerase activities were increased at low dose of TPA and decreased at high dose. The expression levels of human telomerase subunits, human telomerase RNA (hTR) were not influenced by PKC modulating drugs. In contrast, the expression of full-length human telomerase reverse transcriptase (hTERT) was decreased after exposure to bisindolylmaleimide I and Gö6976 in a time-dependent manner. hTERT expression was not affected by low dose of TPA. In contrast, high dose of TPA inhibited hTERT expression level. But the expression patterns of beta-deletion transcript of hTERT after 72 h of treatment with PKC inhibitors or high dose of TPA exposure were not discernable as compared with those of full-length hTERT transcripts to PKC modulating drugs. These results suggest that PKC-modulating drugs altered telomerase activities by affecting full-length hTERT expression profile in human cervical cancers.

Daily survival and human blood index of Anopheles sinensis, the vector species of malaria in Korea

To evaluate the vector efficiency of Anopheles sinensis in transmitting vivax malaria in the northern part of Gyonggi-do, South Korea, daily survival and feeding host preferences were studied during the period of June-October 1999. Ovaries of unfed and freshly fed An. sinensis females were dissected and parity or nulliparity were observed. The parous rates were 75.2% in July, 56.5% in August, 78.5% in September, and 60.0% in October at Gusan-dong, Goyang-si, Gyonggi-do. The average probability of daily survival was 0.890. To determine the host feeding patterns of An. sinensis, outdoor-resting bloodfed mosquitoes were collected, and the sources of the blood meals were analyzed by enzyme-linked immunosorbent assay, using 6 different animal immunoglobulin G antibodies. Out of 305 blood meals tested, 0.7% were positive from humans, 89.8% from bovines, 3.3% from swine, 0.7% from dogs, 1.6% from chickens, and 0.7% from bovines and swine mixed. No blood meals were positive from mice. Though the vector efficiency of An. sinensis was poor because of a low human blood index and a moderate rate of daily survival, vectorial capacity would be high because of high density of the population.

AAC-11 overexpression induces invasion and protects cervical cancer cells from apoptosis

To identify the genes involved in cervical carcinogenesis, we applied the mRNA differential display (DD) method to analyze normal cervical tissue, cervical cancer, metastatic lymph node, and cervical cancer cell line. We cloned a 491-bp cDNA fragment, CC231, which was present in metastatic tissue and cervical cancer cell line, but absent in normal cervical and cervical cancer tissues. The 491 bp cDNA fragment has 98% homology to the previously published sequence, AAC-11 (antiapoptosis clone 11). The levels of AAC-11 mRNA expressions in nine normal cervical and nine primary cervical cancer tissues were low. Its expression was higher in three metastatic tissues and five cervical cancer cell lines (HeLa, CaSki, SiHa, CUMC-3, and CUMC-6). Invasion of matrigel and adhesion to laminin by AAC-11 transfected CUMC-6 cells were increased by approximately 2-fold and 4-fold, respectively. Northern blot analysis showed that matrix metalloproteinase (MMP)-2 and membrane type 1 MMP (MT1-MMP) genes were found to be expressed in high levels in AAC-11-transfected cancer cells. But MMP-2 and MT1-MMP were not expressed in cells transfected with vector alone or wild-type cells. AAC-11-transfected cells expressed an elevated level of MMP-2 protein as assessed by immunoblotting. On the contrary, tissue inhibitor of MMP (TIMP-2) expression was detectable in cells transfected with vector alone or wild-type cells, respectively. Its expression was undetectable in AAC-11 transfected cells. In cervical cancer cells transfected with AAC-11, the expression of beta-catenin was up-regulated. These suggest that overexpressions of MMP-2 and MT1-MMP, loss of TIMP-2 expression, and up-regulation of beta-catenin by AAC-11 transfection may contribute to the development of cervical cancer invasion. AAC-11 gene transfection increased cervical cancer cell colonization. The effect of AAC-11 on cultured cervical cancer cells was associated with antiapoptotic process. Approximately 50% of the AAC-11 transfected cells in serum-free medium died after 2 weeks, compared to 1 week for vector alone or wild-type cells. These results suggest that AAC-11 may serve as a candidate metastasis-related and apoptosis-inhibiting gene in human cervical cancer.

Antisense oligodeoxynucleotide of glyceraldehyde-3-phosphate dehydrogenase gene inhibits cell proliferation and induces apoptosis in human cervical carcinoma cell lines

Tumor cells characteristically exhibit an increased rate of glycolysis. A higher level of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA was found in human uterine cervical cancers. This study was designed using GAPDH antisense oligodeoxynucleotide (ODN) phosphorothioate (PS) to evaluate how alterations of GAPDH expression in human cervical carcinoma could influence growth inhibition and induction of apoptosis. Northern blot analyses revealed that the levels of GAPDH gene expression were strongly elevated in three cervical carcinoma cell lines (HeLa, CUMC-3, and CUMC-6) compared with normal cervical tissue. Reverse transcription-polymerase chain reaction (RT-PCR) showed that expression of the GAPDH gene was inhibited by 10 microM of GAPDH antisense ODN in all three cell lines. Western blot analysis showed that the levels of GAPDH protein were decreased or absent after GAPDH antisense ODN treatment for 12 days in cultured cervical carcinoma cell lines. Cervical carcinoma cell lines exposed to GAPDH antisense ODN showed reduced cellular proliferation, which was accompanied by reduced colony-forming efficiency. This effect of GAPDH antisense ODN on cultured carcinoma cells was associated with the apoptotic process, including increased DNA fragmentation. These results suggest that future gene therapy using antisense ODN directed against cervical cancer-specific GAPDH mRNA might be another therapeutic tool against human uterine cervical carcinomas.

Upregulated expression of the cDNA fragment possibly related to the virulence of Acanthamoeba culbertsoni

Identification of the genes responsible for the recovery of virulence in brain-passaged Acanthamoeba culbertsoni was attempted via mRNA differential display-polymerase chain reaction (mRNA DD-PCR) analysis. In order to identify the regulatory changes in transcription of the virulence related genes by the brain passages, mRNA DD-PCR was performed which enabled the display of differentially transcribed mRNAs after the brain passages. Through mRNA DD-PCR analysis. 96 brain-passaged amoeba specific amplicons were observed and were screened to identify the amplicons that failed to amplify in the non-brain-passaged amoeba mRNAs. Out of the 96 brain-passaged amoeba specific amplicons, 12 turned out to be amplified only from the brain-passaged amoeba mRNAs by DNA slot blot hybridization. The clone, A289C, amplified with an arbitrary primer of UBC #289 and the oligo dT11-C primer, revealed the highest homology (49.8%) to the amino acid sequences of UPD-galactose lipid transferase of Erwinia amylovora, which is known to act as an important virulence factor. The deduced amino acid sequences of an insert DNA in clone A289C were also revealed to be similar to cpsD, which is the essential gene for the expression of type III capsule in group B streptococcus. Upregulated expression of clone A289C was verified by RNA slot blot hybridization. Similar hydrophobicity values were also observed between A289C (at residues 47-66) and the AmsG gene of E. amylovora (at residues 286-305: transmembrane domains). This result suggested that the insert of clone A289C might play the same function as galactosyl transferase controlled by the AmsG gene in E. amylovora.

Pathogenicity of Korean isolates of Acanthamoeba by observing the experimental infection and zymodemes of five isoenzymes

To determine the pathogenicity of Acanthamoeba spp. isolated in Korea and to develop a isoenzymatic maker, the mortality rate of infected mice, in vitro cytotoxicity against target cells and isoenzyme band patterns were observed. Five isolates of Acanthamoeba spp. (YM-2, YM-3, YM-4, YM-5, and YM-7) were used in this study as well as three reference Acanthamoeba spp. (A. culbertsoni, A. hatchetti, and A. royreba). According to the mortality rate of infected mice, Korean isolates could be categorized into three groups high virulent (YM-4), low virulent (YM-2, YM-5, YM-7) and the nonpathogenic group (YM-3). In addition, the virulence of Acanthamoeba spp. was enhanced by brain passage in mice. In the cytotoxicity assay against chinese hamster ovary cells, especially, the cytotoxicity of brain-passaged amoebae was relatively higher than the long-term cultivated ones. The zymodeme patterns of glucose-6-phosphate dehydrogenase (G6PD), malate dehydrogenase (MDH), hexokinase (HK), glutamate oxaloacetate transaminase (GOT) and malic enzyme (ME) of Acanthamoeba spp. were different among each isolate, and also between long-term cultured amoebae and brain passaged ones. In spite of the polymorphic zymodemes, a slow band of G6PD and HK, and an intermediate band of MDH were only observed in pathogenic Acanthamoeba spp., which should be used as isoenzymatic makers.

Growth suppression of human ovarian cancer cell lines by the introduction of a p16 gene via a recombinant adenovirus

OBJECTIVE

The cell cycle regulatory protein p16 (CDKN2/cyclin dependent kinase 4 inhibitor/multiple tumor suppressor-1) causes cell cycle arrest at the G1 checkpoint by inhibiting activity of cyclin D-CDK4 complexes. The purpose of this study is to assess the effect of introduction of the p16 gene into two ovarian cancer cell lines via a recombinant adenoviral vector (Ad5CMV-p16).

METHODS

Cells lines used were SKOV3, which has a p16 deletion, and OVCA420, which has normal p16. Transduction efficiency was established by infecting cells with an adenovirus containing the Escherichia coli beta-galactosidase gene (Ad5CMV-beta-gal) at multiplicity of infection from 0 to 1000 and staining for X-gal. Cells were infected with Ad5CMV-p16 and cell growth was assessed by counting cells every other day for up to 7 days. Western blotting was done to assess for p16 expression after infection. Fluorescence-activated cell sorting after staining with propidium iodide was done to assess the effect of p16 on the cell cycle.

RESULTS

The SKOV3 cell line was transduced with the adenovirus at a slightly lower MOI than the OVCA420 cell line. Growth of the Ad5CMV-p16-infected cells was suppressed 75-80% by cell count in both cell lines and caused morphologic changes of the cells consistent with apoptosis. The p16 protein expression was seen to increase within 24 h after introduction of the p16 gene. G1 arrest of cells occurred beginning 24 h after introduction of the p16 gene.

CONCLUSIONS

These results suggest that Ad5CMV-p16 may be further studied as a potential therapeutic agent for ovarian cancer as introduction of the p16 gene into ovarian cancer cell lines causes a G1 arrest and attenuation of growth, regardless of the endogenous p16 status of the cells.

Comparison of long-term survival of cytomegalovirus promotre versus Rous Sarcoma virus promoter-driven thymidine kinase gene therapy in nude mice bearing human ovarian cancer

The cytomegalovirus (CMV) promoter is considered one of the strongest positive regulators leading to expression of higher levels of the thymidine kinase (TK) enzyme than the Rous Sarcoma virus (RSV) promoter in vitro and in vivo. Cell killing efficacy of adenovirus-mediated CMV promoter-driven herpes simplex virus (HSV) TK gene therapy has been found to be 2 to 10 times more effective than RSV driven HSV-TK gene therapy in vitro. In this study the impact of CMV- versus RSV-driven HSV-TK gene therapy on long-term survival of nude mice bearing human ovarian cancer has been evaluated using a prospective randomized experimental design. The experiment was designed to show significance of survival differences from a 50% increase of survived days at a p-value of 0.05 with a power of 80%. All treatment groups showed an increase in median survival compared with control groups. Treatment benefit was ADV/CMV-TK vector dose dependent. At a given viral dose, no significant prolongation of survival was observed comparing CMV- and RSV-driven ADV-TK indicating that simply increasing cell killing efficacy in vitro above a minimal threshold level using a stronger promoter may not lead to prolongation of survival in the HSV-TK/GCV system.

The efficacy of adenovirus-mediated gene therapy of ovarian cancer is enhanced by using the cytomegalovirus promoter

The cytomegalovirus(CMV) promoter is considered one of the strongest positive regulators. In this study toxicity, cell killing efficacy and bystander effect of Rous Sarcoma Virus(RSV) driven herpes simplex thymidine kinase(TK) gene therapy was compared with CMV driven TK gene therapy in three ovarian cancer cell lines with different growth patterns using a 3-(4,5-dimethylthiazol)-2,5-diphenyl tetra-zolium bromide (MTT) based assay. ADV/CMV-TK was shown to be 2 to 10 times more effective in tumor cell killing than ADV/RSV-TK. The difference in cell killing efficacy between ADV/CMV-TK and ADV/RSV-TK was dependent on the individual cell line. A CMV promoter dependent eight to ten fold improvement in cell killing efficacy was observed in the relatively slow growing SKOV3 cell line which is not easily transducible, while only a 2 to 4 fold difference was observed in the easily transducible OV-CA-2774 and OV-CA-1225 cell lines. ADV/CMV-TK also showed a stronger bystander effect than ADV/RSV-TK in all three ovarian cancer cell lines. Our data demonstrated that the efficacy of adenovirus-mediated gene therapy of ovarian cancer can be enhanced by using the CMV promoter without increasing toxicity.

Improvement of gene therapy for ovarian cancer by using acyclovir instead of ganciclovir in adenovirus mediated thymidine kinase gene therapy

Adenovirus(ADV) mediated thymidine kinase(TK) gene therapy followed by ganciclovir(GCV) administration is widely used in different types of cancer. ACV shares the same mechanism of selective cell killing in ADV/TK positive cells as GCV and can be used at 4.5 times higher doses in patients without significant side effects. An increased dose of TK substrate is associated with improved bystander effect and more efficient cell killing. Toxicity and cell killing efficacy were assessed using a 3-(4,5-dimethylthiazol)-2,5-diphenyl tetrazolium bromide(MTT) based assay in three ovarian cancer cell lines with different proliferation patterns. At the same concentration, equal or higher cell killing efficacy and bystander effect were observed using ACV rather than GCV. 2.5 and 5 times (25 micrograms/ml and 50 micrograms/ml) higher concentrations of ACV always resulted in more effective cell killing than GCV (10 micrograms/ml, P < 0.01). Our data indicate that replacing GCV with ACV in the ADV-TK gene therapy may increase the treatment effect without increasing toxicity.