Preoperative survey to evaluate the patients' allergy list and its relevance to perioperative care.

INTRODUCTION: Perioperative hypersensitivity and allergic reactions can result in significant morbidity and mortality. For routine anesthetic care, allergies are determined from a review of the electronic medical record supplemented by a detailed patient history. Although the electronic medical record is generally assumed to be accurate, it may be that allergies are erroneously listed or not based on sound medical practice. The purpose of the current study is to evaluate allergies listed in the electronic medical record of children presenting for surgery and determine their origin, authenticity, and impact on perioperative care. METHODS: Eligible patients included those presenting for a surgical procedure in the main operating room, who were ≤ 21 years of age, with a drug allergy listed on the EMR. Prior to intraoperative care, an electronic survey questionnaire containing questions related to medication allergies was provided to a guardian or parent. Two anesthesiology physicians reviewed the survey responses to determine the validity of any reported allergies. A second electronic survey was given postoperatively to the attending anesthesiologist to determine whether the documented allergy impacted anesthetic care. RESULTS: The study cohort included 250 patients, ranging in age from 5 to 14 years (median age 9 years). All of the patients had at least one allergy listed on the electronic medical record. Seventy of the 250 patients (28%) had more than one drug allergy listed for a total of 351 medication allergies. The majority of the listed allergies were related to antibiotics including 155 (44%) from the penicillin family, 26 (7%) cephalosporins, 16 (5%) sulfonamides, and 36 (10%) other antimicrobial agents. Other commonly listed allergies were 27 (8%) nonsteroidal anti-inflammatory agents and 15 (4%) opioids. The remaining 76 (22%) included a miscellaneous list of other medications. On further review of the allergies, the survey was completed for 301 medications. After physician review, 135 of 301 (45%) responses were considered consistent with IgE reactions "true allergy," 73 (24%) were deemed less relevant to IgE reactions "unlikely true allergy," and 93 (31%) were not related to IgE reactions "not an allergy." Care alterations during surgery were uncommon regardless of whether the issue was assessed as a true allergy (11%), unlikely to be a true allergy (3%), or not a true allergy (13%). CONCLUSION: A significant portion of the documented allergies in children are not true allergies, but rather recognized adverse effects (apnea from an opioid, renal failure from an NSAIDs) or other nonallergic concerns (gastrointestinal upset such as nausea). Erroneously listed allergies may lead to unnecessary alterations in patient care during perioperative care. A careful analysis of the allergy list on the EMR should be supplemented by a thorough patient history with specific questions related to the drug allergy. Once this is accomplished, the allergy listed should be updated to avoid its erroneous impact on perioperative care.

Pediatric Intraoperative Electromyographic Responses at the Adductor Pollicis and Flexor Hallucis Brevis Muscles: A Prospective, Comparative Analysis.

BACKGROUND: Peripheral nerve stimulation with a train-of-four (TOF) pattern can be used intraoperatively to evaluate the depth of neuromuscular block and confirm recovery from neuromuscular blocking agents (NMBAs). Quantitative monitoring can be challenging in infants and children due to patient size, equipment technology, and limited access to monitoring sites. Although the adductor pollicis muscle is the preferred site of monitoring, the foot is an alternative when the hands are unavailable. However, there is little information on comparative evoked neuromuscular responses at those 2 sites. METHODS: Pediatric patients undergoing inpatient surgery requiring NMBA administration were studied after informed consent. Electromyographic (EMG) monitoring was performed simultaneously in each participant at the hand (ulnar nerve, adductor pollicis muscle) and the foot (posterior tibial nerve, flexor hallucis brevis muscle). RESULTS: Fifty patients with a mean age of 3.0 ± standard deviation (SD) 2.9 years were studied. The baseline first twitch amplitude (T1) of TOF at the foot (12.46 mV) was 4.47 mV higher than at the hand (P <.0001). The baseline TOF ratio (TOFR) before NMBA administration and the maximum TOFR after antagonism with sugammadex were not different at the 2 sites. The onset time until the T1 decreased to 10% or 5% of the baseline value (T1) was delayed by approximately 90 seconds (both P =.014) at the foot compared with the hand. The TOFR at the foot recovered (TOFR ≥0.9) 191 seconds later than when this threshold was achieved at the hand (P =.017). After antagonism, T1 did not return to its baseline value, a typical finding with EMG monitoring, but the fractional recovery (maximum T1 at recovery divided by the baseline T1) at the hand and foot was not different, 0.81 and 0.77, respectively (P =.68). The final TOFR achieved at recovery was approximately 100% and was not different between the 2 sites. CONCLUSIONS: Although this study in young children demonstrated the feasibility of TOF monitoring, interpretation of the depth of neuromuscular block needs to consider the delayed onset and the delayed recovery of TOFR at the foot compared to the hand. The delay in achieving these end points when monitoring the foot may impact the timing of tracheal intubation and assessment of adequate recovery of neuromuscular block to allow tracheal extubation (ie, TOFR ≥0.9).

Tolerance to preoperative placement of electrodes for neuromuscular monitoring using the Tetragraph™.

Background: Quantitative train-of-four (TOF) monitoring has recently been shown to be feasible in infants and children using a novel electromyography (EMG)-based monitor with a pediatric-sized self-adhesive sensor. However, placement of the sensor and initiation of TOF monitoring may require additional time in the operating room (OR), delaying workflow and the time to induction of anesthesia. The current study evaluates the feasibility of placing the self-adhesive sensor in the preoperative holding area in pediatric patients before arrival to the OR. Methods: Consented pediatric patients undergoing inpatient surgery requiring the administration of NMBAs were enrolled. The EMG electrode was placed along the ulnar nerve on the volar aspect of the distal forearm to provide neurostimulation. After the induction of anesthesia, monitoring was initiated and TOF recording started before the administration of the NMBA. A Likert score (0-10) was used to assess ease of placement, tolerability of the monitor during the preoperative period, and its ability to generate a recorded response in the OR. Results: The final study cohort included 40 patients with a median age of 3.7 years. Fourteen patients (35%) pulled off the sensor before arrival to the OR and 26 patients (65%) arrived at the OR with the sensor intact and functioning. Older children were more likely to maintain the sensor until arrival to the OR compared to younger patients (median age of 5.24 versus 1 year, P = 0.0521). A median age of 3.7 years correlated with an 80% chance of arriving in the OR with the sensor intact. Application ease and tolerance of the sensor were higher in the group that maintained the sensor until OR arrival. Conclusion: In patients more than 4 years of age, placement of the self-adhesive sensor for EMG-based TOF monitoring may be feasible. However, in younger patients, additional interventions may be required to achieve a similar success rate.

Use of a Novel Buffered Hypertonic Saline Solution for Fluid Replacement and Resuscitation During Spinal Surgery in Adolescents.

Background: During major orthopedic procedures, such as posterior spinal fusion (PSF), isotonic fluids, colloids, starches, or gelatins are commonly used to replace the preoperative fluid deficit and provide ongoing fluid resuscitation. Given recent concerns regarding the potential adverse physiologic effects of albumin solutions, we have modified our intraoperative practice to include the use of a novel 2% buffered hypertonic saline solution during major orthopedic procedures. We present our preliminary clinical experience with this novel fluid for intraoperative resuscitation and its impact on limiting the use of 5% albumin. Methods: A retrospective review was performed to identify patients who received 2% buffered hypertonic saline during PSF. The intraoperative course of these patients was compared to case-matched control patients who received standard care with isotonic fluids plus 5% albumin as an adjunct for intravascular resuscitation. Results: The study cohort included 23 patients who received 2% buffered hypertonic saline and 25 in the case-matched control group. There was no difference in the volume of intraoperative isotonic crystalloid fluids, estimated blood loss, and urine output between the two groups. In the control cohort, 19 of 25 patients (76%) received 5% albumin compared to only six of 23 patients (26%, P = 0.0005) in the 2% buffered hypertonic saline group. The final pH was higher in the patients that received 2% buffered hypertonic saline than in the control group (7.40 ± 0.03 versus 7.36 ± 0.06, P = 0.0131). Additionally, the starting and final serum sodium values were higher in the patients that received 2% buffered hypertonic saline, although no difference was noted in the mean change from the starting value (average increase of 2 mEq/L in both groups). Conclusion: Use of a novel 2% buffered hypertonic saline solution for intraoperative resuscitation during major orthopedic procedures decreases the need for 5% albumin while avoiding the development of hyperchloremic metabolic acidosis which may occur with standard sodium chloride solutions.

Application of behavioral economic strategies to enhance recruitment into a pediatric randomized clinical trial for postoperative pain relief: A randomized clinical trial.

INTRODUCTION: A major challenge in conducting clinical trials is recruitment. Trial under-enrollment leads to underpowered studies. Behavioral economics offers strategies that may enhance trial recruitment. This study assessed the impact of behavioral economic strategies versus a standard biological approach to recruit children into a randomized clinical trial assessing a biofeedback-based virtual reality intervention for postoperative pain management. We hypothesized the behavioral economics-informed approach would increase enrollment into the future trial, intention to adhere to therapy, acceptability of the intervention, and perceived efficacy while decreasing perception of treatment burden and risk. METHODS: This single-center, prospective, randomized trial recruited patients 12-18 years old undergoing surgery requiring postoperative admission and narcotic administration. Patient-parent dyads were randomized to watch a behavioral economics-informed (n = 64) or standard biological (n = 66) recruitment video about a study designed to assess impact of a virtual reality pain management intervention. RESULTS: There was no difference in rates of intention to enroll in the study between groups (behavioral economics: 75%, control: 79%, p = 0.744) or in median response scores to questions regarding intention to adhere to therapy (4.0 [3.0, 4.0] vs. 4.0 [3.0, 4.0], p=0.084), acceptability of therapy (4.0 [3.0, 4.0] vs. 4.0 [3.0, 4.0], p = 0.376), perceptions of treatment burden (3.0 [3.0, 4.0] vs. 4.0 [3.0, 4.0], p=0.251), and efficacy (3.0 [3.0, 4.0] vs. 3.0 [3.0, 4.0], p = 0.914). Patients in the behavioral economics group were less likely to perceive risk associated with virtual reality versus the control group (behavioral economics: 2.0 [1.0, 2.0], control: 2.0 [2.0, 3.0], p = 0.023). DISCUSSION: A behavioral economics-informed video did not increase patients' intentions to enroll into a clinical trial assessing the impact of virtual reality intervention for postoperative pain management. CONCLUSION: Either approach would be sufficient for patient recruitment for this type of clinical trial since the overall intention to enroll rate was 77%.

Intraoperative electromyographic monitoring in children using a novel pediatric sensor.

Background: Train-of-four (TOF) monitoring is essential in optimizing perioperative outcomes as a means to assess the depth of neuromuscular blockade and confirm recovery following the administration of neuromuscular blocking agents (NMBAs). Quantitative TOF monitoring has been limited in infants and children primarily due to lack of effective equipment. The current study evaluates a novel electromyography (EMG)-based TOF monitor with a recently developed pediatric-sized self-adhesive sensor in infants and children. Methods: Consented pediatric patients undergoing inpatient surgery requiring the administration of NMBAs were enrolled. The EMG electrode was placed along the ulnar nerve on the volar aspect of the distal forearm. The muscle action potentials from the adductor pollicis muscle were recorded throughout surgery at 20-second intervals. Data from the monitor's built-in memory card were later retrieved and analyzed. Results: The final study cohort included 51 patients who ranged in age from 0.2 to 7.9 years and in weight from 4.2 to 36.0 kilograms. Thirty patients weighed less than 15 kgs. Supramaximal stimulus current intensity (mA) at a pulse width of 200 µsec was 30 mA in 8%; 40 mA in 29%; 50 mA in 16%; and 60 mA in 20% of the patients. Supramaximal stimulus current intensity (mA) at a pulse width of 300 µsec was 50 mA in 4%; 60 mA in 24%. The muscle action potential baseline amplitude was 8.7 ± 3.3 mV and recovered to 7.2 ± 3.7 mV after antagonism of neuromuscular blockade. The average baseline TOF ratio was 100 ± 3% and recovered to 98 ± 7% after antagonism of neuromuscular blockade. No technical issues were noted with application of the sensor or subsequent use of the monitor. Conclusion: Neuromuscular monitoring can be performed intraoperatively in pediatric patients who are less than 8 years of age using a novel commercially available EMG-based monitor with a recently developed pediatric sensor. The novel sensor allows use of an EMG-based monitor in infants and children in whom acceleromyography or subjective (visual) observation of the TOF response may not be feasible. Automatic detection of neuromuscular stimulating parameters (supramaximal current intensity level, baseline amplitude of the muscle action potential) was feasible in pediatric patients of all sizes including those weighing less than 15 kilograms or when there was limited access to the extremity being monitored.

Efficacy of an expanded preoperative survey during perioperative care to identify illicit substance use in teenagers and adolescents.

BACKGROUND: As illicit substance use can present several perioperative concerns, effective means to identify such practices are necessary to ensure patient safety. Identification of illicit substance use in pediatric patients may be problematic as screening may rely on parental reporting. AIMS: The current study compares answers regarding use of illicit substances between a survey completed by the patient and the preoperative survey completed by parents or guardians. METHODS: The study included patients presenting for surgery at Nationwide Children's Hospital, ranging in age from 12 to 21 years. After consent, patients completed a survey of six drop-down questions using an iPad. The six questions involved the patient's history of alcohol, tobacco, marijuana, vaping, and opioid use. The results were compared to the answers obtained from the parents during a preoperative phone call. RESULTS: The study cohort included surveys from 250 patients with a median age of 16 years. Survey data showed a statistically higher reporting of substance use or abuse from the patient study survey in comparison to the routine parental preoperative survey. Alcohol report rates were highest with 69 (27.6%) patients reporting use compared to only 5 parental reports (2%). There was a similar discrepancy in reported rates of vaping use (40 patient reports, 16.0% vs. 11 parental reports, 4.4%) and illicit substance use including marijuana (52 patient reports, 20.8% vs. 11 parental reports, 4.4%). Reported rates of tobacco use were lowest among the survey responses with 12 patient reports (4.8%) and 5 parental reports (2.0%). CONCLUSIONS: Identifying illicit substance and tobacco use via a phone survey of parents is inaccurate and does not allow for proper identification of use of these substances in patients ≤21 years of age presenting for surgery. An anonymous 2-min survey completed by the patient more correctly identifies these issues.

Establishing Pediatric Reference Ranges for Rotational Thromboelastometry.

OBJECTIVES: The aim of our investigation was to establish normal pediatric reference intervals (PRIs) for rotational thromboelastometry (ROTEM) Delta assays in a representative group of healthy children, 0 to 18 years of age, at our institution. METHODS: This was a prospective study of healthy pediatric patients undergoing elective minor surgery requiring placement of an intravenous cannula. The sample size for patients was 20 per age group of either sex from 5 different age groups based on coagulation system maturity: 0 to 6 or fewer months, more than 6 to 12 or fewer months, more than 1 year to 5 or fewer years, more than 5 to 11 or fewer years, and more than 11 to 18 or fewer years. ROTEM Delta assays assessed include the EXTEM, INTEM, and FIBTEM. RESULTS: We defined 2 sets of ROTEM PRIs for our patient population: one for patients 11 years or younger and one for children more than 11 years of age. For those 11 years or younger, the PRIs were derived from the 2.5th and 97.5th percentiles from the 0 to 11 age groups. For those older than 11 years, previously published adult reference intervals validated internally with adult normal samples were used. CONCLUSIONS: The 2 sets of PRIs were embedded into our electronic medical record, allowing clinicians to easily interpret their patient's ROTEM results against age-verified reference ranges, enabling them to make informed transfusion decisions.

Acetaminophen pharmacokinetics in infants and children with congenital heart disease.

BACKGROUND: Acetaminophen is routinely used for perioperative analgesia in children undergoing major surgical procedures. There are few estimates of acetaminophen pharmacokinetic parameters in children with congenital heart disease, especially those with cyanotic heart disease. AIMS: The current study prospectively investigated differences in acetaminophen pharmacokinetics following surgery using cardiopulmonary bypass in children with cyanotic and acyanotic congenital heart disease. METHODS: Children (2-6 years, 9-23 kg) presenting for median sternotomy for Fontan palliation (cyanotic patients) or two ventricle surgical repair (acyanotic patients) were eligible for inclusion. A single intravenous dose of acetaminophen (15 mg/kg) was administered at the start of sternal closure after separation from cardiopulmonary bypass. The time-course of acetaminophen concentrations were described using non-linear mixed effects models. One and two-compartment disposition models with first-order elimination were tested. Pharmacokinetic parameter estimates were scaled using allometry and standardized to a 70 kg person. RESULTS: There were 208 acetaminophen concentrations assayed from 30 children, 15 with cyanotic, and 15 with acyanotic heart disease. A 2-compartment model best described acetaminophen PK. Parameter estimates (population parameter variability, PPV%; 95% confidence interval, CI) were clearance CL 15.3 L.h-1.70 kg-1 (22.2%; 13.8-16.7), intercompartment clearance Q 45.4 L.h-1.70 kg-1 (22.4%; 25.2-61.9), central volume of distribution V1 33.5 L.70 kg-1 (23.2%; 25.9-38.8), peripheral volume of distribution V2 32.1 L.70 kg-1 (21.7%; 25.9-38.8). Neither clearance nor volume parameters differed between cyanotic and acyanotic patients. CONCLUSIONS: Acetaminophen pharmacokinetics were characterized using a 2-compartment model with first-order elimination following cardiac bypass surgery in children. Population pharmacokinetic parameter estimates were similar to other studies in children. No differences were detected between patients with cyanotic and acyanotic heart disease.

Noninvasive Blood Pressure Measurement Using the NICCI Monitor in Adolescents During Intraoperative Anesthetic Care.

Background: The intermittent measurement of blood pressure (BP) remains the standard of care during anesthesia or procedural sedation. To improve the early identification of hemodynamic compromise, various noninvasive BP devices have been developed which provide a continuous BP reading. The current study evaluates the accuracy of a novel continuous BP device, the NICCI system, in adolescents weighing 40 - 80 kg. Methods: During intraoperative anesthetic care, BP readings (systolic, diastolic, and mean) were captured from the arterial cannula and the NICCI device every second. Results: The study cohort included 44 pediatric patients undergoing major orthopedic, cardiac, and neurosurgical procedures. A total of 383,126 pairs of systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) values from the arterial cannula and the NICCI device were analyzed. The absolute difference for SBP, DBP, and MAP values from the NICCI monitor and the arterial cannula were 10 ± 8, 9 ± 7, and 9 ± 7 mm Hg, respectively. The difference between the BP values from the NICCI and the arterial cannula was ≤ 10 mm Hg for 60% of the SBP readings, 67% of the DBP readings, and 56% of the MAP readings. Using Bland-Altman analysis, the bias was 2, 3, and 4 mm Hg for the SBP, DBP, and MAP. Conclusions: Although there were technical limitations related to patient size that affected its ability to meet the strict accuracy criteria set by the American National Standards Institute/Association for the Advancement of Medical Instrumentation standards for noninvasive BP measurement (ANSI/AAMI SP10), the NICCI system provided a continuous noninvasive beat-to-beat BP measurement which was clinically relevant during a significant portion of intraoperative care.

An Evaluation of the NICCI Monitor in Providing Continuous, Noninvasive Blood Pressure Readings in Children During Intraoperative Anesthetic Care.

Background: In specific clinical scenarios or with patient comorbid conditions, continuous blood pressure (BP) monitoring may be required as it can be expected to provide superior physiologic monitoring to intermittent techniques. However, continuous BP monitoring requires an arterial cannula (AC) placement, which may be time-consuming, technically challenging, or associated with adverse events. Various noninvasive BP devices have been developed which provide a continuous BP reading. The current study evaluates the accuracy of a novel continuous BP device, the NICCI monitor (NM), in pediatric patients weighing 10 - 40 kg. Methods: The study cohort included pediatric patients weighing between 10 and 40 kg, scheduled for surgery for which placement of an AC was planned. Systolic (SBP), diastolic (DBP), and mean arterial (MAP) blood pressure readings were captured from the AC and the NM every second during anesthetic care. Results: The study cohort included 24 pediatric patients undergoing major orthopedic, cardiac, and neurosurgical procedures. A total of 146,562 pairs of SBP, DBP, and MAP values from the AC and NC were analyzed. The absolute difference for the NM and the AC's SBP, DBP, and MAP values were 11 ± 9, 10 ± 7, and 10 ± 7 mm Hg, respectively. The difference between the BP values from the NM and the AC was ≤ 10 mm Hg for 57% of the SBP readings, 60% of the DBP readings, and 56% of the MAP readings. The bias was 4, 4, and 6 mm Hg for the SBP, DBP, and MAP, respectively. Conclusions: Although there were some technical limitations given patient size, potentially resulting in variation in accuracy, the NM provided a continuous noninvasive BP measurement within clinically useful limits during a significant portion of anesthetic care compared to values obtained from an AC. Ongoing modification of the technology to improve its application in pediatric patients will likely increase its accuracy.