Emad B. Mossad

Fenestration during Fontan palliation: Now the exception instead of the rule

OBJECTIVEnFenestration during Fontan palliation has traditionally been used to decrease surgical morbidity and mortality, particularly in high-risk cases. Potential limitations include oxygen desaturation, risk of paradoxic embolism, and need for late intervention. Our practice has evolved away from routine fenestration with increased extracardiac conduit use. We reviewed our experience with Fontan palliation and retrospectively assessed outcomes with decreased fenestration.nnnMETHODSnBetween January 2002 and April 2008, 226 patients underwent primary Fontan palliation. Outcomes were assessed by hospital stay, chest drain duration, short- and long-term survivals, and late interventions.nnnRESULTSnAnatomic subtypes were single left ventricle (n = 88, 38.9%), single right ventricle (n = 78, 34.5%), common ventricle (n = 19, 8.4%), and heterotaxy syndrome (n = 41, 18.1%). Lateral tunnel connection was created in 69 patients (30.5%); extracardiac connection was created in 157 (69.5%). Mean age and weight at surgery were 4.3 +/- 3.8 years and 17.2 +/- 9 kg, respectively. In 2002, 14 of 16 patients (87.5%) had fenestrated Fontan circulations, versus 2 of 32 (6.3%) in 2008. Mean hospital stay was 10.8 +/- 8.8 days. Survival to discharge or 30 days was 98.7%. There were 2 (0.9%) late deaths during mean follow-up of 2.0 +/- 1.7 years. Outcomes were equivalent between fenestrated and nonfenestrated procedures across anatomic subtypes.nnnCONCLUSIONSnHighly selective use of Fontan fenestration is achievable while maintaining excellent outcomes without increased surgical morbidity or mortality, irrespective of anatomic subtype. Risks of hypoxia, systemic embolism, and late instrumentation can be avoided in most cases.

Impact of dexmedetomidine on early extubation in pediatric cardiac surgical patients

PurposeTo evaluate the impact of dexmedetomidine on early extubation in post-operative pediatric cardiac patients compared to patients on standard sedation regimens without dexmedetomidine.MethodsRetrospective study comparing dexmedetomidine infusion (DEX) to our standard sedation regimens (control).ResultsA total of 269 patients were included (control: nxa0=xa0180; DEX: nxa0=xa089). The mean duration of DEX was 34xa0±xa02xa0h. Extubation was achieved in the operating room in 42% of the control group and 42% of the DEX group. Extubation within 24xa0h of surgery was achieved in 75% of the control group and 76% of the DEX group. Ventilator time in the DEX group was 35xa0±xa029xa0h compared to 29xa0±xa035xa0h in the control group. The mean cardiovascular intensive care unit (CV ICU) and hospital length of stays were 3xa0±xa02 and 8xa0±xa04xa0days in the DEX group and 3xa0±xa03 and 8xa0±xa05xa0days in the control group. Reintubation rates in the CV ICU were not significantly different. DEX patients received significantly less total intraoperative fentanyl and midazolam but significantly more midazolam rescue doses than the control group in the postoperative period. Post-extubation ventilation was clinically similar in the DEX group as measured by 1xa0h post-extubation PaCO2 levels.ConclusionsDexmedetomidine did not significantly impact the postoperative course of children compared to standard practice as measured by success of early extubation, ventilator time, and length of stay.

Perioperative management of pediatric patients on mechanical cardiac support

The population of children with end‐stage heart failure requiring mechanical circulatory support is growing. These children present for diagnostic imaging studies, various interventions and noncardiac surgical procedures that require anesthetic care. This article is a review of the population demographics of children on mechanical cardiac support, the alternative devices available, and the important concepts for safe perioperative management of these patients. The discussion will be limited to devices for short‐ and long‐term cardiac support, excluding extracorporeal membrane oxygenation (ECMO) for respiratory support.

Lung reperfusion injury in patients after balloon angioplasty for pulmonary artery stenosis.

OBJECTIVESnTo determine the incidence and degree of acute lung reperfusion injury (ARI) in patients undergoing balloon angioplasty of branch pulmonary artery stenosis and to evaluate the correlation and efficacy of an oxygenation index in confirming the clinical diagnosis.nnnDESIGNnRetrospective, single-center observational study.nnnSETTINGnCardiac catheterization laboratory at a tertiary care childrens hospital.nnnPATIENTSnPatients with congenital heart disease undergoing pulmonary artery balloon angioplasty.nnnINTERVENTIONnReview of patient medical and catheterization records.nnnMEASUREMENTS AND MAIN RESULTSnThe records of all patients with biventricular physiology undergoing balloon angioplasty of branch pulmonary artery stenosis over a period of 2 years (12/2006-12/2008) were reviewed. Data collection included demographics, details of pulmonary artery intervention, right ventricle/femoral artery systolic pressure (RV/FA) ratio, and post-procedure recovery condition. Markers of ARI, including clinical, radiographic, and blood gas analysis, were examined. Criteria for ARI were based on the International Society of Heart and Lung Transplantation (ISHLT) grading system, in which a PaO2/FIO2 of 200 to 300 indicates ARI. The distribution of PaO2/FIO2 after pulmonary artery intervention, the relation of clinical to laboratory manifestation of ARI, and the correlation among different oxygenation indices were examined. During the study period, 46 patients with congenital heart disease and branch pulmonary artery stenosis were identified. Patient age ranged from 2 months to 25 years (mean 6.2±6 years) and weight ranged from 5 to 86 kg (mean 23±18 kg). ARI was identified in 10 of 46 patients (22%) using clinical criteria and correlated with ISHLT gas exchange criteria. Analysis of RV/FA ratio before (0.82±0.34) and after (0.71±0.22) balloon angioplasty revealed statistically significant decrease (p<0.004). The degree of ARI was graded using ISHLT criteria and correlated with the presence of clinical symptoms (p<0.002). As anticipated, the PaO2/FIO2 ratio had a strong correlation with A-aDO2 (r = 0.75) and SpO2/FIO2 (r = 0.7) and a strong specificity (0.78) to identify patients with clinical ARI.nnnCONCLUSIONnARI often can occur after pulmonary artery interventions. The PaO2/FIO2 is a valuable test for identifying patients at risk of developing ARI and can help guide the care of these patients in the postintervention period.

Standard clinical risk factors for difficult laryngoscopy are not independent predictors of intubation success with the GlideScope

STUDY OBJECTIVESnTo determine whether the first-attempt tracheal intubation incidence using the GlideScope videolaryngoscope is higher in patients with predicted increased risk of difficult laryngoscopy, and to assess the ability of other a priori defined standard risk factors to predict first-attempt intubation success, in aggregate and by forming scores.nnnDESIGNnProspective study.nnnSETTINGnOperating room in a tertiary-care academic center.nnnPATIENTSn357 patients intubated with the GlideScope for nonemergent general anesthesia.nnnINTERVENTIONS AND MEASUREMENTSnMallampati airway class was used to create two groups of patients, one with higher and the other, lower, potential difficult laryngoscopy (Mallampati classes 3-4 and 1-2, respectively). Intubation success on the first attempt with the GlideScope videolaryngoscope in patients with a Mallampati class 3 or 4 airway versus those with Mallampati class 1 or 2 airway was tested. We also evaluated the predictive ability of the Mallampati airway class (1 and 2 vs 3 and 4) along with 9 other possible predictors of difficult intubation on first-attempt intubation success: gender, age, body mass index, level of training within our anesthesia residency program (Clinical Anesthesia Resident years 1, 2, and 3), ASA physical status, mouth opening, thyromental distance, neck flexion, and neck extension.nnnMAIN RESULTSnNone of the standard predictors of difficult intubation was significantly associated with outcome after adjusting for other predictors. A multivariable model containing the aggregate set of variables predicted outcome significantly better than a risk score formed as the sum of 10 predictors (Risk 10; P = 0.0176).nnnCONCLUSIONSnWith GlideScope-assisted tracheal intubation, Mallampati airway class is not an independent risk factor for difficult intubation. Other standard clinical risk factors of difficulty with direct laryngoscopy also do not appear to be individually predictive of first-attempt success of tracheal intubation.

Limitations of Cerebral Oxygenation Monitoring by Near-Infrared Spectroscopy in Children With Cyanotic Congenital Heart Disease and Profound Polycythemia

In this case series, a group of 10 patients with significantly high preoperative hematocrit secondary to congenital cardiovascular disease for whom regional cerebral oxygen saturation was unmeasureable via nearinfrared spectroscopy were identified. Institutional review board approval was obtained for the review of records and data collection for patients with failure of intraoperative NIRS detection. In a period of 1 year (2010), 10 of 1,820 (0.55%) patients were identified intraoperatively and in the cardiac catheterization laboratory with failed NIRS monitoring and profound polycythemia (ie, hematocrit values significantly above the laboratory reference range). After the induction of anesthesia, appropriate-sized bilateral INVOS 5100 sensors (Somanetics Corp, Troy, MI) were placed on the patient’s forehead. If the rSO2 was unobtainable (failure to display a value on the monitor screen), the probes were removed and placed on the attending anesthesiologist to confirm that the probes and equipment were functional. The probes were replaced onto the patient’s forehead, and again an rSO2 value failed to display. Data collection included demographics, hematocrit, hemodynamic variables, and ventilatory variables, and the presence or absence of rSO2 detection was recorded with every arterial blood gas analysis.

Anesthesia and Databases: Pediatric Cardiac Disease as a Role Model.

Large data sets have now become ubiquitous in clinical medicine; they are particularly useful in high-acuity, low-volume conditions such as congenital heart disease where data must be collected from many centers. These data fall into 2 categories: administrative data arising from hospital admissions and charges and clinical data relating to specific diseases or procedures. In congenital cardiac diseases, there are now over a dozen of these data sets or registries focusing on various elements of patient care. Using probabilistic statistic matching, it is possible to marry administrative and clinical data post hoc using common elements to determine valuable information about care patterns, outcomes, and costs. These data sets can also be used in a collaborative fashion between institutions to drive quality improvement (QI). Because these data may include protected health information (PHI), care must be taken to adhere to federal guidelines on their use. A fundamental principle of large data management is the use of a common language and definition (nomenclature) to be effective. In addition, research derived from these information sources must be appropriately balanced to ensure that risk adjustments for preoperative and surgical factors are taken into consideration during the analysis. Care of patients with cardiac disease both in the United States and abroad consistently shows wide variability in mortality, morbidity, and costs, and there has been a tremendous amount of discussion about the benefits of regionalization of care based on center volume and outcome measurements. In the absence of regionalization, collaborative learning techniques have consistently been shown to minimize this variability and improve care at all centers, but before changes can be made it is necessary to accurately measure accurately current patient outcomes. Outcomes measurement generally falls under hospital-based QI initiatives, but more detailed analysis and research require Institutional Review Board and administrative oversight. Cardiac anesthesia providers for these patients have partnered with the Society of Thoracic Surgeons Congenital Heart surgeons to include anesthesia elements to help in this process.

CASE 14—2014 Tetralogy of Fallot With Severe Cyanosis in an Infant With Trisomy 18: Ethical Dilemmas in the Perioperative Period

From the Baylor College of Medicine, Texas Children’s Hospital, Houston, TX. J.R.W. is cardiac anesthesia fellow. Address reprint requests to Jamie R.Wingate, MD, Baylor College of Medicine, Texas Children’s Hospital, 6621 Fannin Street, WT, 17317B, Houston, TX 77030. E-mail: hwarraic@bidmc.harvard.edu

Anesthetic Considerations for Adults Undergoing Fontan Conversion Surgery

There are currently in North America more adults with congenital heart disease than children. This article discusses the anesthetic considerations in adults with single-ventricle physiology and prior repairs who present for Fontan conversion surgery as a demonstration of the challenges of caring for adults undergoing interventions for the repair of congenital heart defects. The care of these patients requires an understanding of the impact of passive pulmonary blood flow and single systemic ventricular physiology. The perioperative morbidity in this patient population remains high.

Dexmedetomidine utilisation and outcomes of children with trisomy 21 undergoing congenital heart disease surgery

INTRODUCTIONnThe diagnosis of trisomy 21 in children has been associated with failed extubation after CHD surgery. Dexmedetomidine may be a useful agent to improve postoperative outcomes in these patients, such as ventilator time, ICU length of stay, or hospital length of stay.nnnMATERIALS AND METHODSnThe Pediatric Health Information System database was queried from January, 2008 to December, 2010 for patients with trisomy 21 who underwent CHD surgery. Patients who received dexmedetomidine were matched to patients who did not by propensity score. The primary outcome was ventilator days charged, and secondary outcomes included ICU and hospital length of stay.nnnRESULTSnA total of 1088 patients (544 matched pairs) met inclusion criteria. Patient characteristics were similar, with the exception of more patients in the dexmedetomidine group undergoing repair of complete atrioventricular canal and fewer undergoing mechanical valve replacement (p<0.01). More patients in the dexmedetomidine group were administered milrinone, epinephrine, vasopressin, benzodiazepines, opiates, and adjunct pain and sedative medications (p<0.01). The dexmedetomidine group had greater time on the ventilator [7 (4.5-11) versus 6 (4-10) days (median, interquartile range) p<0.01] and similar ICU length of stay, hospital length of stay, and mortality compared with controls. Mixed-effects modelling clustered on institution did not show beneficial effect of dexmedetomidine on ventilator time, ICU stay, or hospital length of stay.nnnCONCLUSIONSnThe use of dexmedetomidine was not associated with the decreased ventilatory time. Routine use of dexmedetomidine is not warranted in this patient population.