Andreas H. Taenzer

Pediatric Regional Anesthesia Network (PRAN): a multi-institutional study of the use and incidence of complications of pediatric regional anesthesia.

BACKGROUND: Regional anesthesia is increasingly used in pediatric patients to provide postoperative analgesia and to supplement intraoperative anesthesia. The Pediatric Regional Anesthesia Network was formed to obtain highly audited data on practice patterns and complications and to facilitate collaborative research in regional anesthetic techniques in infants and children. METHODS: We constructed a centralized database to collect detailed prospective data on all regional anesthetics performed by anesthesiologists at the participating centers. Data were uploaded via a secure Internet connection to a central server. Data were rigorously audited for accuracy and errors were corrected. All anesthetic records were scrutinized to ensure that every block that was performed was captured in the database. Intraoperative and postoperative complications were tracked until their resolution. Blocks were categorized by type and as single-injection or catheter (continuous) blocks. RESULTS: A total of 14,917 regional blocks, performed on 13,725 patients, were accrued from April 1, 2007 through March 31, 2010. There were no deaths or complications with sequelae lasting >3 months (95% CI 0–2:10,000). Single-injection blocks had fewer adverse events than continuous blocks, although the most frequent events (33% of all events) in the latter group were catheter-related problems. Ninety-five percent of blocks were placed while patients were under general anesthesia. Single-injection caudal blocks were the most frequently performed (40%), but peripheral nerve blocks were also frequently used (35%), possibly driven by the widespread use of ultrasound (83% of upper extremity and 69% of lower extremity blocks). CONCLUSIONS: Regional anesthesia in children as commonly performed in the United States has a very low rate of complications, comparable to that seen in the large multicenter European studies. Ultrasound may be increasing the use of peripheral nerve blocks. Multicenter collaborative networks such as the Pediatric Regional Anesthesia Network can facilitate the collection of detailed prospective data for research and quality improvement.

Impact of pulse oximetry surveillance on rescue events and intensive care unit transfers: a before-and-after concurrence study.

Background:Some preventable deaths in hospitalized patients are due to unrecognized deterioration. There are no publications of studies that have instituted routine patient monitoring postoperatively and analyzed impact on patient outcomes. Methods:The authors implemented a patient surveillance system based on pulse oximetry with nursing notification of violation of alarm limits via wireless pager. Data were collected for 11 months before and 10 months after implementation of the system. Concurrently, matching outcome data were collected on two other postoperative units. The primary outcomes were rescue events and transfers to the intensive care unit compared before and after monitoring change. Results:Rescue events decreased from 3.4 (1.89–4.85) to 1.2 (0.53–1.88) per 1,000 patient discharges and intensive care unit transfers from 5.6 (3.7–7.4) to 2.9 (1.4–4.3) per 1,000 patient days, whereas the comparison units had no change. Conclusions:Patient surveillance monitoring results in a reduced need for rescues and intensive care unit transfers.

Incidence of local anesthetic systemic toxicity and postoperative neurologic symptoms associated with 12,668 ultrasound-guided nerve blocks: an analysis from a prospective clinical registry.

Background and Objectives There are varying reports on the incidence of major morbidity associated with peripheral regional anesthesia. Our objective was to contribute to the knowledge regarding the incidence of local anesthetic systemic toxicity and postoperative neurologic symptoms in the setting of ultrasound-guided peripheral regional anesthesia. Methods During an 8-year period, 12,668 patients undergoing peripheral regional anesthesia were evaluated. Using a clinical registry, incidence rates of postoperative neurologic symptoms, local anesthetic toxicity, pneumothorax, and vascular trauma were calculated. Univariate analysis was used to identify risk factors for postoperative neurologic symptoms. We defined postoperative neurologic symptoms as any sensory or motor dysfunction present for more than 5 days and anatomically consistent with the possibility of contribution from the nerve block. Results The incidence (per 1000 blocks) of adverse events across all peripheral regional anesthetics was 1.8 (95% confidence interval [CI], 1.1–2.7) for postoperative neurologic symptoms lasting longer than 5 days, 0.9 (95% CI, 0.5–1.7) for postoperative neurologic symptoms lasting longer than 6 months, 0.08 (95% CI, 0.0–0.3) for seizure, 0 (95% CI, 0–0.3) for pneumothorax, 0.6 (95% CI, 0.2–1.2) for unintended venous puncture, 1.2 (95% CI, 0.7–2.0) for unintended arterial puncture, and 2.0 (95% CI, 1.2–3.0) for patients having unintended paresthesia during block placement. There were no cardiac arrests. Conclusions In the setting of a surgical procedure, ultrasound-guided regional anesthesia is associated with the risk of long-term postoperative neurologic symptoms. Local anesthetic systemic toxicity, however, is extremely uncommon.

A Review of Current and Emerging Approaches to Address Failure-to-Rescue

Failure-to-Rescue, defined as hospital deaths after adverse events, is an established measure of patient safety and hospital quality. Until recently, approaches used to address failure-to-rescue have been focused primarily on improvement of response to a recognized patient crisis, with limited success in terms of patient outcomes. Less attention has been paid to improving the detection of the crisis. A wealth of retrospective data exist to support the observation that adverse events in general ward patients are preceded by a significant period (on the order of hours) of physiologic deterioration. Thus, the lack of early recognition of physiologic decline plays a major role in the failure-to-rescue problem.

Gender affects report of pain and function after arthroscopic anterior cruciate ligament reconstruction.

BACKGROUND Gender-related differences in pain have been clearly shown in experimental settings. Clinical studies of such differences have produced conflicting findings. No studies have shown a significant difference in pain experience associated with differences in functional outcomes. Arthroscopic anterior cruciate ligament reconstruction (AACLR) produces pain of moderate intensity and provides a useful setting for examining gender-related differences in pain and function. METHODS This study was a retrospective review of prospectively gathered data collected for a continuous quality improvement program and involved all patients who underwent AACLR at a single outpatient facility since June 1992. Anesthetic, surgical, and perioperative management techniques were standardized. Using a questionnaire, all patients were routinely asked to record pain scores, narcotic consumption, and whether they were able to perform a standardized straight leg-raising maneuver on each of the first 5 postoperative days. RESULTS A total of 736 patients were enrolled for surgery, 58% of whom completed the entire 5-day questionnaire. Women reported higher pain scores at rest as well as with activity on postoperative day 1 compared with men (P < 0.005). In addition, fewer women were able to perform the straight leg-raising maneuver on postoperative day 1 (P = 0.002) and postoperative day 2 (P = 0.004). There was no difference in the amount of narcotics consumed at any time during the study period. CONCLUSIONS Women seem to experience greater intensity of pain after AACLR that is associated with a decrease in an intermediate measure of functional outcome. These differences may result from differences in either response to analgesics or neuroprocessing.

Asleep versus awake: does it matter?: Pediatric regional block complications by patient state: a report from the Pediatric Regional Anesthesia Network.

Background and Objectives The impact of the patient state at time of placement of regional blocks on the risk of complications is unknown. Current opinion is based almost entirely on case reports, despite considerable interest in the question. Analyzing more than 50,000 pediatric regional anesthesia blocks from an observational prospective database, we determined the rate of adverse events in relation to the patient’s state at the time of block placement. Primary outcomes considered were postoperative neurologic symptoms (PONSs) and local anesthetic systemic toxicity (LAST). Secondary outcome was extended hospital stay due to a block complication. Methods The Pediatric Regional Anesthesia Network is a multi-institutional research consortium that was created with an emphasis on rigorous, prospective, and complete data collection including a data validation and audit process. For the purpose of the analysis, blocks were divided in major groups by single injection versus continuous and by block location. Rates were determined in aggregate for these groups and classified further based on the patient’s state (general anesthesia [GA] without neuromuscular blockade [NMB], GA with NMB, sedated, and awake) at the time of block placement. Results Postoperative neurological symptoms occurred at a rate of 0.93/1000 (confidence interval [CI], 0.7–1.2) under GA and 6.82/1000 (CI, 4.2–10.5) in sedated and awake patients. The only occurrence of PONSs lasting longer than 6 months (PONSs-L) was a small sensory deficit in a sedated patient (0.019/1000 [CI, 0–0.1] for all, 0.48/1000 [CI, 0.1–2.7] for sedated patients). There were no cases of paralysis. There were 5 cases of LAST or 0.09/1000 (CI, 0.03–0.21). The incidence of LAST in patients under GA (both with and without NMB) was 0.08/1000 (CI, 0.02–0.2) and 0.34/1000 (CI, 0–1.9) in awake/sedated patients. Extended hospital stays were described 18 times (0.33/1000 [CI, 0.2–0.53]). The rate for patients under GA without NMB was 0.29/1000 (CI, 0.13–0.48); GA with NMB, 0.29/1000 (CI, 0.06–0.84); sedated, 1.47/1000 (CI, 0.3–4.3); and awake, 1.15/1000 (CI, 0.02–6.4). Conclusions The placement of regional anesthetic blocks in pediatric patients under GA is as safe as placement in sedated and awake children. Our results provide the first prospective evidence for the pediatric anesthesia community that the practice of placing blocks in anesthetized patients should be considered safe and should remain the prevailing standard of care. Prohibitive recommendations based on anecdote and case reports cannot be supported.

Apnea after Awake Regional and General Anesthesia in Infants: The General Anesthesia Compared to Spinal Anesthesia Study-Comparing Apnea and Neurodevelopmental Outcomes, a Randomized Controlled Trial

Background:Postoperative apnea is a complication in young infants. Awake regional anesthesia (RA) may reduce the risk; however, the evidence is weak. The General Anesthesia compared to Spinal anesthesia study is a randomized, controlled trial designed to assess the influence of general anesthesia (GA) on neurodevelopment. A secondary aim is to compare rates of apnea after anesthesia. Methods:Infants aged 60 weeks or younger, postmenstrual age scheduled for inguinal herniorrhaphy, were randomized to RA or GA. Exclusion criteria included risk factors for adverse neurodevelopmental outcome and infants born less than 26 weeks gestation. The primary outcome of this analysis was any observed apnea up to 12 h postoperatively. Apnea assessment was unblinded. Results:Three hundred sixty-three patients were assigned to RA and 359 to GA. Overall, the incidence of apnea (0 to 12 h) was similar between arms (3% in RA and 4% in GA arms; odds ratio [OR], 0.63; 95% CI, 0.31 to 1.30, P = 0.2133); however, the incidence of early apnea (0 to 30 min) was lower in the RA arm (1 vs. 3%; OR, 0.20; 95% CI, 0.05 to 0.91; P = 0.0367). The incidence of late apnea (30 min to 12 h) was 2% in both RA and GA arms (OR, 1.17; 95% CI, 0.41 to 3.33; P = 0.7688). The strongest predictor of apnea was prematurity (OR, 21.87; 95% CI, 4.38 to 109.24), and 96% of infants with apnea were premature. Conclusions:RA in infants undergoing inguinal herniorrhaphy reduces apnea in the early postoperative period. Cardiorespiratory monitoring should be used for all ex-premature infants.

A Comparison of Oxygen Saturation Data in Inpatients with Low Oxygen Saturation Using Automated Continuous Monitoring and Intermittent Manual Data Charting

BACKGROUND:The manual collection and charting of traditional vital signs data in inpatient populations have been shown to be inaccurate when compared with true physiologic values. This issue has not been examined with respect to oxygen saturation data despite the increased use of this measurement in systems designed to assess the risk of patient deterioration. Of particular note are the lack of available data examining the accuracy of oxygen saturation charting in a particularly vulnerable group of patients who have prolonged oxygen desaturations (mean SpO2 <90% over at least 15 minutes). In addition, no data are currently available that investigate the often suspected “wake up” effect, resulting from a nurse entering a patient’s room to obtain vital signs. METHODS:In this study, we compared oxygen saturation data recorded manually with data collected by an automated continuous monitoring system in 16 inpatients considered to be at high risk for deterioration (average SpO2 values <90% collected by the automated system in a 15-minute interval before a manual charting event). Data were sampled from the automatic collection system from 2 periods: over a 15-minute period that ended 5 minutes before the time of the manual data collection and charting, and over a 5-minute range before and after the time of the manual data collection and charting. Average saturations from prolonged baseline desaturations (15-minute period) were compared with both the manual and automated data sampled at the time of the nurse’s visit to analyze for systematic change and to investigate the presence of an arousal effect. RESULTS:The manually charted data were higher than those recorded by the automated system. Manually recorded data were on average 6.5% (confidence interval, 4.0%–9.0%) higher in oxygen saturation. No significant arousal effect resulting from the nurse’s visit to the patient’s room was detected. CONCLUSIONS:In a cohort of patients with prolonged desaturations, manual recordings of SpO2 did not reflect physiologic patient state when compared with continuous automated sampling. Currently, early warning scores depend on manual vital sign recordings in many settings; the study data suggest that SpO2 ought to be added to the list of vital sign values that have been shown to be recorded inaccurately.

Interscalene brachial plexus blocks under general anesthesia in children: is this safe practice?: A report from the Pediatric Regional Anesthesia Network (PRAN).

Background and Objectives A practice advisory on regional anesthesia in children in 2008, published in this journal, supported the placement of regional blocks in children under general anesthesia (GA). Interscalene brachial plexus (IS) blocks were specifically excluded, based on case reports (level 3 evidence) of injury, which occurred predominantly in heavily sedated or anesthetized adult patients. Apart from case reports, there is a paucity of data that explore the safety of IS blocks placed in patients under GA, and the level of evidence available on which to base recommendations is limited. Methods Querying the database of the Pediatric Regional Anesthesia Network (PRAN), we report on the incidence of postoperative neurological symptoms, local anesthetic systemic toxicity, and other reported adverse events in children receiving IS blocks under GA or sedated. Results A total of 518 interscalene blocks were performed, 390 under GA and 123 with the patient sedated or awake (5 cases had missing status); 472 of these were single injection, and 46 involved the placement of infusion catheters. Eighty-eight percent of blocks were placed with ultrasound guidance, 7.7% with no location device, and 2.5% with a nerve stimulator. No local anesthetic systemic toxicity, postoperative neurological symptoms, cardiovascular complications, or dural puncture was reported in this cohort. There were 1 vascular puncture and 1 postoperative infection. These negative results are compatible with 0 to 7.7/1000 events for each of these complications for IS blocks placed under GA. There was no paralysis, motor block, or sensory deficit beyond the expected block duration time. Conclusions Analyzing interscalene blocks in children placed under GA, we identified no serious adverse events. The upper limit of the confidence interval for these events is similar to that in awake or sedated adults receiving IS blocks. Based on these prospectively collected data, placement of IS blocks under GA in children is no less safe than placement in awake adults, calling into question the American Society of Regional Anesthesia and Pain Medicine advisory proscribing GA during IS block in pediatric patients.

Experience with 724 epidurograms for epidural catheter placement in pediatric anesthesia.

Introduction: Epidural analgesia via continuous catheters, placed either via the caudal approach or directly at the desired level, is a commonly used technique in children. It is particularly important that these catheters are placed correctly because most are placed under general anesthesia and require deep sedation or repeat general anesthesia for replacement if malfunctioning. Ideally, correct placement should be confirmed at the time of insertion. Methods: We combined the experience of 2 academic teaching hospitals that both perform routine epidurography for the placement of epidural catheters in children. The data from 2 quality assurance regional anesthesia databases were screened for unrecognized misplacements of epidural catheters. Results: Of a total of 724 epidurograms, 45.8% were caudal catheters, 9.6% were lumbar catheters, and 32.3% were thoracic catheters. Epidurograms detected 12 (1.6%) unexpected misplacements: 4 were intrathecal, 3 were intravenous, and 3 were intraperitoneal. Conclusions: Our experiments suggest that confirmation of epidural catheter placement via epidurogram is highly efficacious. Epidurography is the only currently available technique that accomplishes all of the following: (a) confirms correct placement, (b) rules out incorrect anatomic space, and (c) predicts analgesic coverage.