Impact of Genetic Disorders in the Surgical Management of Congenital Heart Disease

The congenital heart surgeon frequently encounters patients with various genetic disorders requiring surgical intervention. Although the specifics of the genetics for these patients and their families lie in the purview of specialists in genetics, the surgeon is well-served to be familiar with aspects of specific syndromes that impact surgical management and perioperative care. This aids in counseling families in expectations for the hospital course and recovery as well as can impact intraoperative and surgical management. This review article summarizes key characteristics for the congenital heart surgeon to be familiar with for common genetic disorders as they help coordinate care.

Low Utilization of Synchronous Telemedicine in Pediatric Critical Care Interfacility Transport: Barriers and Lessons

OBJECTIVE

The use of telemedicine has increased and may enhance the care of children during medical transport. We aimed to evaluate the feasibility of synchronous telemedicine connectivity before interfacility transport of critically ill children by a pediatric transport team.

METHODS

We performed a prospective, observational feasibility study of the introduction of synchronous telemedicine into an established pediatric transport team from 2019 to 2020. The outcomes examined included connectivity, physician workload, transport team satisfaction, and patient care outcomes.

RESULTS

Among 118 eligible transports, telemedicine was considered in 23 transports (19%), including 11 transports in which an attempt to connect was sought and 12 in which telemedicine activation was offered but not attempted. The median connection time was 2.9 minutes (interquartile range, 1.7-4.4 minutes), and clinical care was altered in 1 case. Connection failed in 2 cases (18.2%). In 50% of cases, concurrent medical control physician workload prevented activation. There were no perceived benefits in 41.7% of cases. Team members indicated the desire for future telemedicine use in only 54.6% of cases.

CONCLUSIONS

We found low utilization of synchronous telemedicine in interfacility pediatric transport. The identified barriers included reliable connectivity, physician workload, and low perceived benefit. Lessons learned and future research suggestions are presented to mitigate these barriers.

Acute Kidney Injury and Renal Replacement Therapy After Fontan Operation

Fontan circulation leads to chronic elevation of central venous pressure. We sought to identify the incidence, risk factors, and survival among patients who developed acute kidney injury (AKI) after the Fontan operation. We retrospectively reviewed 1,166 patients who had Fontan operation/revision at Mayo Clinic Rochester from 1973 to 2017 and identified patients who had AKI (defined by AKI Network criteria) within 7 days of surgery. A total of 132 patients (11%) developed AKI after the Fontan operation with no significant era effect. Of those who developed AKI, severe (grade 3) kidney injury was present in 101 patients (76.5%). Multivariable risk factors for AKI were asplenia (odds ratio [OR] 4.2, p <0.0001), elevated preoperative pulmonary artery pressure (per 1 mm Hg increase, OR 1.04, p = 0.0002), intraoperative arrhythmias (OR 1.9, p = 0.02), and elevated post-bypass Fontan pressure (per 1 mm Hg increase, OR 1.12, p = 0.0007). Renal replacement therapy (RRT) was used in 72 patients (54%), predominantly through peritoneal dialysis (n = 56, 78%). Multivariable risk factors for RRT were age ≤3 years (OR 9.7, p = 0.0004), female gender (OR 2.6, p = 0.02), and aortic cross-clamp time >60 minutes (OR 3.1, p = 0.01). Patients with AKI had more postoperative complications, including bleeding, stroke, pericardial tamponade, low cardiac output state and cardiac arrest, than those without AKI. This resulted in longer intensive care unit stay (39 vs 17 days, p = 0.0001). In-hospital mortality was exceedingly higher among patients with AKI versus no AKI (58%, 76 of 132 vs 10%, 99 of 1,034, p <0.0001); however, there was no significant difference based on the need for RRT. Recovery from AKI was observed in 56 patients (42%). Over 20-year follow-up, patients with AKI had a distinctly higher all-cause-mortality (82%) than those without AKI (35%). It is prudent to identity patients at a higher risk of developing postoperative AKI after Fontan operation to ensure renal protective strategies in the perioperative period. Postoperative AKI leads to substantial short and long-term morbidity and mortality, but the need for RRT does not affect the outcomes.

Hypotension and adverse neurodevelopmental outcomes among children with multiple exposures to general anesthesia: Subanalysis of the Mayo Anesthesia Safety in Kids (MASK) Study

BACKGROUND

The potential adverse effects of exposures to general anesthesia on the developing human brain remain controversial. It has been hypothesized that hypotension accompanying anesthesia could be contributory. We hypothesized that among children exposed to multiple anesthetics prior to age 3, children developing adverse neurodevelopmental outcomes would be more likely to have intraoperative hypotension.

METHODS

Two previously published study cohorts were utilized for analysis: the retrospective and prospective Mayo Anesthesia Safety in Kids cohorts. The two lowest consecutive systolic blood pressure measurements were abstracted and standardized by calculating a z-score for noninvasive blood pressure reference ranges for children. The lowest systolic blood pressure z-score (continuous variable) and intraoperative hypotension (lowest systolic blood pressure z-score <-1.0) were used to assess the association of intraoperative hypotension with the incidence of learning disabilities or attention-deficit/hyperactivity disorder(retrospective cohort) and factor scores/cluster membership (prospective cohort).

RESULTS

One hunderd and sixteen and 206 children with multiple exposures to general anesthesia were analyzed in the retrospective and prospective cohorts with mean lowest systolic blood pressure z-scores -0.26 (SD 1.02) and -0.62 (SD 1.10), respectively. There was no overall association of the lowest z-score or hypotension with learning disabilities or attention-deficit/hyperactivity disorder in the retrospective cohort. In the prospective cohort, there was no overall association of the lowest systolic blood pressure or hypotension with factor scores or cluster membership.

CONCLUSIONS

We did not find evidence to support the hypothesis that, among children exposed to multiple anesthetics prior to age 3, children developing adverse neurodevelopmental outcomes would be more likely to have intraoperative hypotension compared with those who did not.

Improvement in Oxygenation Utilizing Transpulmonary Pressure Monitoring for Optimal Positive End-Expiratory Pressure in Pediatric Acute Respiratory Distress Syndrome: A Case Report

In severe pediatric acute respiratory distress syndrome, data are lacking on methods to measure and set optimal positive end-expiratory pressure. We present a 2-year-old girl with Trisomy 21 who developed severe pediatric acute respiratory distress syndrome and refractory hypoxemia from human metapneumovirus pneumonia. Esophageal manometry was utilized to measure transpulmonary pressure, and positive end-expiratory pressure was increased to 19 cm H2O, resulting in rapid improvement in oxygenation. Hemodynamics remained adequate without intervention. The patient improved and survived without sequelae. Our case suggests that transpulmonary pressure monitoring should be studied as an adjunct to improve outcomes in pediatric acute respiratory distress syndrome.

Innovative 2-Step Management Strategy Utilizing EXIT Procedure for a Fetus With Hypoplastic Left Heart Syndrome and Intact Atrial Septum

Hypoplastic left heart syndrome (HLHS) with intact atrial septum (HLHS-IAS) carries a high risk of mortality and affects about 6% of all patients with HLHS. Fetal interventions, postnatal transcatheter interventions, and postnatal surgical resection have all been used, but the mortality risk continues to be high in this subgroup of patients. We describe a novel, sequential approach to manage HLHS-IAS and progressive fetal hydrops. A 28-year-old, gravida 4 para 2 mother was referred to Mayo Clinic for fetal HLHS. Fetal echocardiography at 28 weeks of gestation demonstrated HLHS-IAS with progressive fetal hydrops. The atrial septum was thick and muscular with no interatrial communication. Ultrasound-guided fetal atrial septostomy was performed with successful creation of a small atrial communication. However, fetal echocardiogram at 33 weeks of gestation showed recurrence of a pleural effusion and restriction of the atrial septum. We proceeded with an Ex uteroIntrapartum Treatment (EXIT) delivery and open atrial septectomy. This was performed successfully, and the infant was stabilized in the intensive care unit. The infant required venoarterial extracorporeal membrane oxygenator support on day of life 1. The patient later developed hemorrhagic complications, leading to his demise on day of life 9. This is the first reported case of an EXIT procedure and open atrial septectomy performed without cardiopulmonary bypass for an open-heart operation and provides a promising alternative strategy for the management of HLHS-IAS in select cases.

Epidemiology of general anesthesia prior to age 3 in a population-based birth cohort

BACKGROUND

Utilization of general anesthesia in children has important policy, economic, and healthcare delivery implications, yet there is little information regarding the epidemiology of these procedures in the United States.

AIMS

The primary objective of this study was to describe in a geographically defined population the incidence of procedures requiring general anesthesia up to the child's third birthday, and the patient characteristics associated with receiving these procedures. A secondary objective was to determine the proportion of children in the population who meet the risk criteria promulgated by the Food and Drug Administration (FDA).

METHODS

A retrospective cohort of children born from 1994 to 2007 in Olmsted County, MN was established. Birth certificate information and receipt of general anesthesia before age 3 were collected. Proportional hazard regressions were performed to evaluate the association between characteristics of children and incidence of general anesthesia.

RESULTS

Among the 20 922 children in the cohort, 3120 (14.9%) underwent at least 1 general anesthesia before age 3. In multivariate regression, factors independently associated with receiving at least 1 procedure included prematurity, male sex, lower birth weight, cesarean delivery, a non-Hispanic mother, and a White mother, controlling for multiple gestation, number of children previously born, age, education, and marital status of the mother. Seven hundred and twenty-three children (3.5%) had at least 1 subsequent procedure. Estimated gestational age <32 weeks and low birth weight were independently associated with receiving repeated anesthesia. Eight hundred and twenty children (3.9%) had a single prolonged exposure above 3 hours, multiple exposures prior to age 3, or both.

CONCLUSION

Approximately 1 in 7 children were exposed to at least 1 episode of general anesthesia before age 3, and approximately 1 in 4 children who received general anesthesia fall within the high-risk category as defined by the recent FDA warning. The apparent disparities in surgical utilization related to race and ethnicity in this study population deserve further exploration.

Design and α-testing of an electronic rounding tool (CERTAINp) to improve process of care in pediatric intensive care unit

Increasing process complexity in the pediatric intensive care unit (PICU) can lead to information overload resulting in missing pertinent information and potential errors during morning rounds. An efficient model using a novel electronic rounding tool was designed as part of a broader critical care decision support system-checklist for early recognition and treatment of acute illness and injury in pediatrics (CERTAINp). We aimed to evaluate its impact on improving the process of care during rounding. Prospective pre- and post-interventional data included: team performance baseline assessment, patient safety discussion, guideline adherence, rounding time, and a survey of Residents' and Nurses' perception using a Likert scale. Attending physicians were blinded to the components of the assessment. A total of 113 pre-intervention and 114 post-intervention roundings were recorded by direct observation. Pre-intervention (108) and post-intervention staff surveys (80) were obtained. Adherence to standard of care guidelines improved to >97 % in all data points, with maximum increase seen in discussions of ulcer prophylaxis, bowel protocol, DVT prophylaxis, skin care, glucose control and head of bed elevation (2-28 % pre-vs. 100 % for all post-intervention, p < 0.01). Significant improvement was noticed in spontaneous breathing trials, sedation breaks and need for devices (45-57 % pre- vs. 100 % for all post-intervention, p < 0.01). Rounding time (mean ± SD) increased by 2 min/patient (8.0 ± 5.8 min pre-intervention vs. 9.9 ± 5.7 min post-intervention, p = 0.002). Staff reported improved perception of all aspects of rounding. Utilization of the CERTAINp rounding tool led to perfect compliance to the discussion of best practice guidelines; had minimal impact on rounding time and improved PICU staff satisfaction.

An automated real-time method for the detection of patients at risk for malignant hyperthermia

BACKGROUND

Malignant hyperthermia (MH) is a rare anesthetic pharmacogenetic disorder that can be difficult to detect in its earliest phases. Prompt treatment is known to improve outcomes. The modern anesthesia information management systems (AIMS) collect enormous amounts of data. However, data lack context and are not able to provide real-time guidance. Utilizing our AIMS, we developed the capacity to incorporate decision support.

AIMS

We describe the creation and evaluation of a real-time detection tool for MH.

METHODS

Cases of MH from 2003 to 2013 were retrospectively reviewed to confirm the diagnosis of MH and to calculate a MH clinical grading scale score. The index cases were utilized to develop four electronic data Rules, based on endtidal CO2 (ETCO2 ) and temperature criteria. The Rules were then applied retrospectively to the index cases and to a full cohort of general operating room (OR) patients from January 2012 to June 2012. If criteria for possible MH was met, the detection tool generated an alert on the monitor at the patient's bedside.

RESULTS

We identified seven patients with confirmed MH with MH Scores ranging from 28 to 70. Using four data Rules, all of our seven index cases were captured and generated an appropriate alert. Median time from MH computer alert time to dantrolene administration time among our index cases was 23 min (IQR 17-77). There were 938 false-positive alerts for possible MH (1.8%) when the Rules were applied to a general OR cohort of 51 579 total cases from January 2012 to June 2012.

CONCLUSIONS

We demonstrated a real-time MH detection tool based on established physiologic criteria that is sensitive enough to capture cases suspicious for MH, while limiting false positives to prevent alarm fatigue. This has the potential to notify the provider of possible MH such that treatment may be rapidly initiated.

Improvement in Patient Transfer Process From the Operating Room to the PICU Using a Lean and Six Sigma-Based Quality Improvement Project

BACKGROUND AND OBJECTIVES

Ineffective and inefficient patient transfer processes can increase the chance of medical errors. Improvements in such processes are high-priority local institutional and national patient safety goals. At our institution, nonintubated postoperative pediatric patients are first admitted to the postanesthesia care unit before transfer to the PICU. This quality improvement project was designed to improve the patient transfer process from the operating room (OR) to the PICU.

METHODS

After direct observation of the baseline process, we introduced a structured, direct OR-PICU transfer process for orthopedic spinal fusion patients. We performed value stream mapping of the process to determine error-prone and inefficient areas. We evaluated primary outcome measures of handoff error reduction and the overall efficiency of patient transfer process time. Staff satisfaction was evaluated as a counterbalance measure.

RESULTS

With the introduction of the new direct OR-PICU patient transfer process, the handoff communication error rate improved from 1.9 to 0.3 errors per patient handoff (P = .002). Inefficiency (patient wait time and non-value-creating activity) was reduced from 90 to 32 minutes. Handoff content was improved with fewer information omissions (P < .001). Staff satisfaction significantly improved among nearly all PICU providers.

CONCLUSIONS

By using quality improvement methodology to design and implement a new direct OR-PICU transfer process with a structured multidisciplinary verbal handoff, we achieved sustained improvements in patient safety and efficiency. Handoff communication was enhanced, with fewer errors and content omissions. The new process improved efficiency, with high staff satisfaction.

Construction and Characterization of a Population-Based Cohort to Study the Association of Anesthesia Exposure with Neurodevelopmental Outcomes

Exposure to general anesthesia at an early age has been associated with adverse neurodevelopmental outcomes in both animal and human studies, but some of these studies employed anesthetic agents that are no longer in clinical use. In this manuscript, we describe the methods used to construct a new population-based study cohort to study the association between early anesthetic exposure and subsequent neurodevelopmental outcomes. A birth cohort of all children born in Olmsted County, MN from January 1, 1996 to December 31, 2000 was identified. For each, school enrollment status in the Independent School District (ISD) 535 at age 5 or 6 and all episodes of anesthetic exposure before age 3 were identified. A study cohort was created by matching children enrolled in ISD 535 based on the propensity of receiving general anesthesia. Three analyses were performed to characterize the study cohort by comparing the birth and parental information, comorbidities, and socioeconomic status. The first analysis compared the characteristics of birth cohort children who were and were not enrolled in ISD 535. The second analysis evaluated the success of the propensity matching schemes in creating groups of children that were similar in measured characteristics except for anesthesia exposure. The third analysis compared the characteristics of children with anesthesia exposures who were and were not included in the final cohort based on propensity matching. Results of these analyses demonstrate only slight differences among the comparison groups, and therefore these are unlikely to compromise our future analysis of anesthetic exposure and neurodevelopmental outcomes.

Neurodevelopment of children exposed to anesthesia: design of the Mayo Anesthesia Safety in Kids (MASK) study

There is increasing evidence that exposure of developing brains in animals, including nonhuman primates, to commonly-utilized anesthetic agents may cause adverse effects on cognition and behavior. In this paper, we summarize our methodology for a population-based, propensity-matched study to evaluate possible anesthesia-related sequelae in preschool children when evaluated in elementary or high school. A cohort of all children born in Olmsted County, Minnesota between the years 1994 and 2007 who are currently local residents has been identified. Existing medical records are being used to identify all episodes of exposure to general anesthesia prior to the age of 3 years (i.e., prior to their 3rd birthday). Children with multiple, single, and no anesthesia exposure are sampled for testing between the ages of 8 and 12 years or 15 and 19 years during the period 2012-2016. To match children in different exposure groups as closely as possible, sampling is guided by propensity-matching for the likelihood of receiving anesthesia. Selected children are invited to participate in a single 4-hour session of neuropsychological testing, including the National Center for Toxicological Research-Operant Test Battery, which has been used to study anesthetic neurotoxicity in nonhuman primates. The results of this testing will be compared among children with different anesthetic exposure histories. The expected products of this research will be a detailed phenotype of possible anesthetic-associated neurotoxicity in humans, utilizing a robust patient database and neuropsychological testing battery, and the first comparison of effects of anesthetic exposure in children and nonhuman primates performing nearly identical behavioral tasks.

Perioperative outcomes of severely obese children undergoing tonsillectomy

BACKGROUND

Sleep-disordered breathing, a common condition in obese children, is a frequent indication for tonsillectomy.

OBJECTIVE

The purpose of this study was to examine the association between obesity and perioperative complications in children undergoing tonsillectomy.

METHODS/MATERIALS

A sample of 100 severely obese children (body mass index for age [BMIA], ≥ 98 th percentile) between ages 2 and 18 years who underwent tonsillectomy at Mayo Clinic Rochester was randomly selected. Each severely obese child was age (± 2 years) and sex matched to two normal weight children (BMIA between 25th and 75th percentiles) undergoing tonsillectomy during the study period, and their medical records were reviewed.

RESULTS

Severely obese children had a significantly higher incidence of comorbid conditions including respiratory disorders and severe systemic disorders or syndromes. Severely obese children had a higher frequency of perioperative airway complications (15.0% vs 2.0%). From posthoc analyses, severe obesity remained a significant risk factor for perioperative adverse events after adjusting for the presence of severe systemic disorders or syndromes (OR 8.8; 95% CI 2.8-27.5, P < 0.001) and also after adjusting for preoperative respiratory disorders (OR 7.7; 95% CI 2.5-24.3, P < 0.001). When children with planned admissions were excluded from the analysis, severe obesity was associated with an increased rate of unplanned hospital admission (OR 3.80, 95% CI 1.8-7.9, P < 0.001).

CONCLUSIONS

Severe obesity in children undergoing tonsillectomy is independently associated with an increased risk of perioperative complications. It appears that both severe obesity and systemic comorbid condition contribute to higher proportions of inpatient tonsillectomies performed in our institution.

Forearm vascular conductance during mental stress is related to the heart rate response

The forearm vasodilator response to mental stress is multifactorial and widely variable among individuals. We evaluated the association between the heart rate and forearm vascular conductance (FVC) responses to a color word test in 101 healthy adults. We found a striking correlation between heart rate and FVC (r = 0.66, P < 0.001), which remained significant when controlling for subject characteristics, blood pressure, and catecholamines. This suggests that the mechanical stimulation is one of the key factors that contribute to the increase in FVC during mental stress.

Intraoperative extracorporeal membrane oxygenation and survival of pediatric patients undergoing repair of congenital heart disease

BACKGROUND

We studied the association between the introduction of extracorporeal membrane oxygenation (ECMO) into routine practice and the survival of children who failed weaning from cardiopulmonary bypass (CPB). We compare two periods, before formal introduction of ECMO in our institution (1993-1999, pre-ECMO era) and after ECMO became a formalized program (2000-2006, ECMO era).

METHODS

Retrospective review of Mayo Clinic Database between 1993 and 2006 for outcomes of patients <18 years old who required ECMO during repair of congenital heart malformations.

RESULTS

Thirty-five children during ECMO era received intraoperative ECMO, and 17 (54%) survived to hospital discharge. The frequency of ECMO use was the highest in neonates, therefore, this was the only subcohort of pediatric patients that allowed comparison of survival between the pre-ECMO and ECMO eras. When compared to pre-ECMO era, neonatal survival increased during ECMO era (P = 0.043). ECMO was mostly used in neonates with higher complexity of cardiac defects undergoing more complex repairs, and the overall improvement of survival was primarily due to better survival of these patients. During pre-ECMO era, survival was lower in patients with higher risk (P = 0.001). However, during ECMO era, no difference in survival was observed across assigned risk groups (P = 0.658).

CONCLUSIONS

The availability of ECMO for neonates failing to wean from CPB was associated with improved survival, especially in children undergoing repair of the most complex congenital heart malformations. After introduction of ECMO, survival improved and no longer depended upon the complexity of surgical repair.

Perioperative cardiac arrests in children between 1988 and 2005 at a tertiary referral center: a study of 92,881 patients

BACKGROUND

The objective of this study was to determine the incidence and outcome of perioperative cardiac arrest (CA) in children younger than 18 yr undergoing anesthesia for noncardiac and cardiac procedures at a tertiary care center.

METHODS

After institutional review board approval (Mayo Clinic, Rochester, Minnesota), all patients younger than 18 yr who had perioperative CA between November 1, 1988, and June 30, 2005, were identified. Perioperative CA was defined as a need for cardiopulmonary resuscitation or death during anesthesia care. A cardiac procedure was defined as a surgical procedure involving the heart or great vessels requiring an incision.

RESULTS

A total of 92,881 anesthetics were administered during the study period, of which 4,242 (5%) were for the repair of congenital heart malformations. The incidence of perioperative CA during noncardiac procedures was 2.9 per 10,000, and the incidence during cardiac procedures was 127 per 10,000. The incidence of perioperative CA attributable to anesthesia was 0.65 per 10,000 anesthetics, representing 7.5% of the 80 perioperative CAs. Both CA incidence and mortality were highest among neonates (0-30 days of life) undergoing cardiac procedures (incidence: 435 per 10,000; mortality: 389 per 10,000). Regardless of procedure type, most patients who experienced perioperative CA (88%) had congenital heart disease.

CONCLUSION

The majority of perioperative CAs were caused by factors not attributed to anesthesia, in distinction to some recent reports. The incidence of perioperative CA is many-fold higher in children undergoing cardiac procedures, suggesting that definition of case mix is necessary to accurately interpret epidemiologic studies of perioperative CA in children.

The risk of malignant hyperthermia in children undergoing muscle biopsy for suspected neuromuscular disorder

BACKGROUND

It is assumed that those children with known or suspected neuromuscular disorders (NMD) are at increased risk for malignant hyperthermia (MH). Despite the lack of conclusive data, most of these children are managed with a nontriggering anesthetic. This study examined the risk of MH in children exposed to a triggering anesthetic while undergoing muscle biopsy for suspected NMD.

METHODS

Between 1992 and 2005, the medical records of 351 children under 21 years of age were identified as having undergone muscle biopsy for suspected NMD. Of these, only 274 received a volatile anesthetic agent or succinylcholine and were included for study. Records were examined for evidence of MH or rhabdomyolysis.

RESULTS

No patient exhibited signs or symptoms suggestive of MH. One patient was found, by muscle biopsy, to have evidence of rhabdomyolysis prior to exposure to a volatile anesthetic. Of 274 patients, only three received succinylcholine. None developed MH or rhabdomyolysis. The estimated risk of a patient with suspected NMD developing MH as a result of exposure to volatile anesthetic agents during muscle biopsy is 1.09% or less.

CONCLUSION

The estimated risk of MH or rhabdomyolysis is 1.09% or less in a diverse population of children with suspected NMD.