Assistant Professor - Med Center Line, Anesthesiology, Perioperative and Pain Medicine
Fellowship:UCSF Anesthesiology Fellowships (2010) CA
Residency:UCSF Anesthesiology Residency (2009) CA
Medical Education:University of California at San Francisco School of Medicine (2005) CA
Board Certification: Pediatric Anesthesia, American Board of Anesthesiology (2013)
Fellowship:Stanford Medical Center - Anesthesia (2011) CA
Internship:Stanford Hospital and Clinics - Dept of Surgery (2006) CA
Board Certification: Anesthesia, American Board of Anesthesiology (2010)
- Implementing Machine Learning in Health Care - Addressing Ethical Challenges NEW ENGLAND JOURNAL OF MEDICINE 2018; 378 (11): 981–83
Anticipating uncertainty and irrevocable decisions: provider perspectives on implementing whole-genome sequencing in critically ill children with heart disease.
Genetics in medicine : official journal of the American College of Medical Genetics
PurposeTo investigate the potential impacts of whole-genome sequencing (WGS) in the pediatric critical-care context, we examined how clinicians caring for critically ill children with congenital heart disease (CHD) anticipate and perceive the impact of WGS on their decision-making process and treatment recommendations.MethodsWe conducted semistructured in-person and telephone interviews of clinicians involved in the care of critically ill children with CHD at a high-volume pediatric heart center. We qualitatively analyzed the transcribed interviews.ResultsIn total, 34 clinicians were interviewed. Three themes emerged: (i) uncertainty about the accuracy of WGS testing and adequacy of testing validation; (ii) the use of WGS to facilitate life-limiting decisions such as futility, rationing, and selective prenatal termination; and (iii) moral distress over using WGS with a lack of decision support.ConclusionDespite uncertainty about WGS testing, the interviewed clinicians were using, and anticipated expanding the use of, WGS results to justify declarations of futility, withdrawal of care, and rationing in critically ill children with CHD. This situation is causing moral distress in providers who have to make high-stakes decisions involving WGS results, with only partial understanding of them. Decision support for clinicians, and discussion with families of the risks of using WGS for rationing or withdrawal, is needed.Genet Med advance online publication, 1 March 2018; doi:10.1038/gim.2018.25.
View details for DOI 10.1038/gim.2018.25
View details for PubMedID 29493583
Genomic Contraindications for Heart Transplantation.
Genome sequencing raises new ethical challenges. Decoding the genome produces new forms of diagnostic and prognostic information; however, the information is often difficult to interpret. The connection between most genetic variants and their phenotypic manifestations is not understood. This scenario is particularly true for disorders that are not associated with an autosomal genetic variant. The analytic uncertainty is compounded by moral uncertainty about how, exactly, the results of genomic testing should influence clinical decisions. In this Ethics Rounds, we present a case in which genomic findings seemed to play a role in deciding whether a patient was to be listed as a transplant candidate. We then asked experts in bioethics and cardiology to discuss the implications of such decisions.
View details for DOI 10.1542/peds.2016-3471
View details for PubMedID 28255068
View details for PubMedCentralID PMC5369679
- CPR and Ventricular Assist Devices: The Challenge of Prolonging Life Without Guaranteeing Health. American journal of bioethics 2017; 17 (2): 1-2
- The Advance of Rescue Technologies and the Border of Viability. The American journal of bioethics : AJOB 2017; 17 (8): 40–41
- Pediatric Acute Care Decision Implications of Genetically Discoverable Mental Disorders AMERICAN JOURNAL OF BIOETHICS 2017; 17 (4): 32-33
Can Destination Therapy be implemented in children with heart failure? A study of provider perceptions.
2016; 20 (6): 819-824
DT is an established final therapeutic choice in adult patients with severe heart failure who do not meet criteria for cardiac transplantation. Patients are given VADs, without the prospect of care escalation to transplantation. VADs are now established therapy for children and are currently used as a bridge until transplantation can be performed or heart failure improves. For children who present in severe heart failure but do not meet transplantation criteria, the question has emerged whether DT can be offered. This qualitative study aimed to elicit the perspectives of early adopters of DT at one of the few institutions where DT has been provided for children. Responses were recorded and coded and themes extracted using grounded theory. Interviewees discussed: envisioning of the DT candidate; approach to evaluation for DT; contraindications to choosing DT; and concerns about choosing DT. Providers articulated two frameworks for conceptualizing DT: as a long bridge through resolution of problems that would initially contraindicate transplantation or, alternatively, as a true destination instead of transplantation. True destination, however, may not be the lasting concept for long-term VAD use in children given improvement in prognosis for current medical contraindications and improving VAD technology.
View details for DOI 10.1111/petr.12747
View details for PubMedID 27357389
- Anesthesia Intraoperative Handoffs: Is Decision Ownership Compatible With Transitions of Care Providers? American journal of bioethics 2016; 16 (9): 19-20
Anesthesia for Placement of a Paracorporeal Lung Assist Device and Subsequent Heart-Lung Transplantation in a Child with Suprasystemic Pulmonary Hypertension and End-Stage Respiratory Failure.
A & A case reports
2016; 6 (10): 308-310
Pediatric patients with end-stage respiratory failure and pulmonary hypertension traditionally have poor outcomes when bridged with extracorporeal membrane oxygenation to lung or heart-lung transplantation. Therefore, several institutions have attempted paracorporeal lung assist devices as a bridge. However, given the small number of patients, little is known about approaches to anesthetic induction in these hemodynamically unstable patients either before placement of a device or anesthetic induction once a device is in situ. In this case report, we describe our anesthetic experience managing a 13-year-old boy for both paracorporeal lung assist device placement and subsequent heart-lung transplantation.
View details for DOI 10.1213/XAA.0000000000000300
View details for PubMedID 27002753
Cognitive Dysfunction in Children with Heart Disease: The Role of Anesthesia and Sedation.
Congenital heart disease
2016; 11 (3): 221-229
As physicians and caregivers of children with congenital heart disease, we are aware of the increasing need for procedures requiring anesthesia. While these procedures may be ideal for medical and cardiac surgical management, the risks and benefits must be assessed carefully. There are well known risks of cardiovascular and respiratory complications from anesthesia and sedation and a potentially under-appreciated risk of neurocognitive dysfunction. Both animal and human studies support the detrimental effects of repeated anesthetic exposure on the developing brain. Although the studies in humans are less convincing of this risk, the Society of Pediatric Anesthesia jointly with SmartTots provided a consensus statement on the use of anesthetic and sedative drugs in infants and toddlers when speaking to families. (www.pedsanesthesia.org; http://smarttots.org/wp-content/uploads/2015/10/ConsensusStatementV910.5.2015.pdf). An excerpt of the statement is "Concerns regarding the unknown risk of anesthetic exposure to your child's brain development must be weighed against the potential harm associated with cancelling or delaying a needed procedure. Each child's care must be evaluated individually based on age, type, and urgency of the procedure and other health factors. This review provides a summary of the current evidence regarding anesthesia-induced neurotoxicity and the developing brain and its implications for children with congenital heart disease.
View details for DOI 10.1111/chd.12352
View details for PubMedID 27228360
Accuracy of Pulse Oximeters Intended for Hypoxemic Pediatric Patients.
Pediatric critical care medicine
2016; 17 (4): 315-320
Prior studies have shown inaccuracies in pulse oximetry readings at saturations less than 85%; however, no large studies have evaluated new sensors marketed for these low saturations. This study's purpose was to evaluate two sensors with claims of improved accuracy in children with saturations less than 85%.Prospective observational study.Single institution; cardiac catheterization laboratory, and operating room.Fifty patients weighing 3-20 kg with baseline saturations less than 90% undergoing surgical or catheterization procedure.Data collected included demographics, diagnosis, continuous saturations from three different pulse oximeters (Masimo LNCS [Masimo, Irvine, CA], Masimo Blue [Masimo], and Nellcor Max-I [Medtronic, Dublin, Ireland]) and up to four blood samples for co-oximetry as the gold-standard arterial oxygen saturation. Analysis included scatter plots, smoothed regression estimates of mean continuous saturation levels plotted against corresponding arterial oxygen saturation values, and Bland-Altman plots. Bland-Altman analysis indicated increasing levels of bias and variability for decreasing arterial oxygen saturation levels for all three sensors, with a statistically significant increase in mean difference observed for decreasing arterial oxygen saturation level. The Masimo Blue sensor had the lowest mean difference, SD and Bland-Altman limits in patients with saturations less than or equal to 85%. At saturation range of less than or equal to 85% and greater than 75%, 14% of the samples obtained from Masimo Blue, 24% of the readings from the Nellcor, and 31% from the Masimo Standard sensors were greater than or equal to 5% points difference. All three sensors had a further increase in these differences for arterial oxygen saturation values less than 75%.The Masimo Blue sensor has improved accuracy at saturations 75-85% versus the Nellcor and Masimo Standard sensors. The accuracy of peripheral capillary oxygen saturation of the Masimo Blue sensor was within 5% points of the arterial oxygen saturation the majority of the time. Currently, at saturations less than or equal to 85%, pulse oximetry alone should not be relied on in making clinical decisions.
View details for DOI 10.1097/PCC.0000000000000660
View details for PubMedID 26914626
- Accuracy of Pulse Oximeters Intended for Hypoxemic Pediatric Patients PEDIATRIC CRITICAL CARE MEDICINE 2016; 17 (4): 315-320
- Supervised Controlled Substance Use. American journal of bioethics 2016; 16 (4): 56-58
- How should whole-genome sequencing be implemented in children? A consideration of the current limitations PERSONALIZED MEDICINE 2016; 13 (1): 33-42
- Parental Refusal of Newborn Screening for Congenital Hearing Loss. American journal of bioethics 2016; 16 (1): 33-35
- Negotiating the dilemma of anaesthesia and sedation in NICUs. The Lancet. Respiratory medicine 2015; 3 (10): 741-742
- Ethics of Disclosure Regarding Drug Shortages That Affect Patient Care. Anesthesia and analgesia 2015; 121 (2): 262-263
- Whole-genome sequencing in critically ill infants and emerging ethical challenges. The Lancet. Respiratory medicine 2015; 3 (5): 333-335
- Whole genome sequencing in critically ill children. The Lancet. Respiratory medicine 2015; 3 (4): 264-266
- Preventive Genomic Sequencing and Care of the Individual Patient. American journal of bioethics 2015; 15 (7): 32-33
- Ethical concerns raised among pediatric heart failure clinicians. American journal of bioethics 2015; 15 (5): 36-37
- Are preoperative B-type natriuretic peptide levels associated with outcome after pulmonary artery banding and the double switch operation in patients with congenitally corrected transposition of the great arteries: A pilot study JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY 2014; 148 (5): 2434-2436
- Are preoperative B-type natriuretic peptide levels associated with outcome after pulmonary artery banding and the double switch operation in patients with congenitally corrected transposition of the great arteries: a pilot study. journal of thoracic and cardiovascular surgery 2014; 148 (5): 2434-2436
Preoperative B-type natriuretic peptide levels are associated with outcome after total cavopulmonary connection (Fontan).
journal of thoracic and cardiovascular surgery
2014; 148 (1): 212-219
The study objective was to determine the association between preoperative B-type natriuretic peptide levels and outcome after total cavopulmonary connection. Surgical palliation of univentricular cardiac defects requires a series of staged operations, ending in a total cavopulmonary connection. Although outcomes have improved, there remains an unpredictable risk of early total cavopulmonary connection takedown. The prediction of adverse postoperative outcomes is imprecise, despite an extensive preoperative evaluation.We prospectively enrolled 50 patients undergoing total cavopulmonary connection. We collected preoperative clinical data, preoperative plasma B-type natriuretic peptide levels, and postoperative outcomes, including the incidence of an adverse outcome within 1 year of surgery (defined as death, total cavopulmonary connection takedown, or the need for cardiac transplantation).The mean age of patients was 4.7 years (standard deviation, 2.1 years). The median (interquartile range) preoperative B-type natriuretic peptide levels were higher in patients who required total cavopulmonary connection takedown and early postoperative mechanical cardiac support (n = 3; median, 55; interquartile range, 42-121) compared with those with a good outcome (n = 47; median, 11; interquartile range, 5-17) (P < .05). A preoperative B-type natriuretic peptide level of 40 pg/mL or greater was highly associated with the need for total cavopulmonary connection takedown (sensitivity, 100%; specificity, 93%; P < .05), yielding a positive predictive value of 50% and a negative predictive value of 100%. Higher preoperative B-type natriuretic peptide levels also were associated with longer intensive care unit length of stay, longer hospital length of stay, and increased incidence of low cardiac output syndrome (P < .05).Preoperative B-type natriuretic peptide blood levels are uniquely associated with the need for mechanical support early after total cavopulmonary connection and total cavopulmonary connection takedown, and thus may provide important information in addition to the standard preoperative assessment.
View details for DOI 10.1016/j.jtcvs.2013.08.009
View details for PubMedID 24079880
General anesthesia treatment of propriospinal myoclonus in a patient with fibrodysplasia ossificans progressiva.
A & A case reports
2014; 3 (1): 6-8
Fibrodysplasia ossificans progressiva, a rare and severely disabling genetic condition, is characterized clinically by progressive ossification of skeletal muscle and connective tissue and congenital malformations of the great toes. Recurrent episodes of heterotopic ossification (flare-ups) lead to increasing loss of mobility as joints become progressively affected. We report the case of a young woman with fibrodysplasia ossificans progressiva who had recurrent, debilitating myoclonus that was refractory to conventional therapies but was relieved for prolonged periods after general anesthesia was administered.
View details for DOI 10.1213/XAA.0000000000000037
View details for PubMedID 25612266
- Unintended effects on morale of mandatory postincident testing. American journal of bioethics 2014; 14 (12): 42-44
The effects of ketamine on dexmedetomidine-induced electrophysiologic changes in children.
2013; 23 (10): 898-905
BACKGROUND: Dexmedetomidine is an alpha2-adrenergic agonist used for sedation and analgesia in children. We previously showed that dexmedetomidine depresses sinus and AV nodal function resulting in adverse hemodynamic effects such as bradycardia and increased blood pressure. We hypothesized that these effects of dexmedetomidine might be antagonized by co-administration of ketamine, which has sympathomimetic properties. METHODS: Twenty-two children (ages 5-17 years) undergoing electrophysiologic (EP) study and ablation for supraventricular tachycardia were enrolled. Patients were kept sedated with continuous infusion of propofol at a fixed rate. Hemodynamic and EP parameters were measured before and after a loading dose of dexmedetomidine (1 μg·kg(-1) ). A continuous infusion of dexmedetomidine (0.7 μg·kg(-1) ·h(-1) ) was initiated and a ketamine loading dose (1 mg·kg(-1) ), followed by continuous infusion (1 mg·kg(-1) ·h(-1) ), was given. A repeat set of hemodynamic and EP parameters were then measured at the time of projected peak tissue concentration for both drugs. RESULTS: A significant increase in mean arterial pressure (MAP) was seen compared with baseline after loading of dexmedetomidine. This returned to baseline after co-administration of ketamine (mean difference between baseline and after ketamine 1.8 mmHg; 95%CI, -7.8 to 4.3; P = <0.001). A decrease in heart rate was seen after dexmedetomidine followed by a return to baseline after co-administration of ketamine (mean difference between baseline and after ketamine -6.5 bpm; 95%CI, -11.2 to -1.8; P = 0.005). Sinus node recovery time was lengthened after dexmedetomidine but returned to baseline after ketamine (mean difference between baseline and after ketamine -16.2 ms; 95%CI, -63 to 30; P = 0.014). QT was prolonged after dexmedetomidine and returned to baseline after ketamine (mean difference between baseline and after ketamine -34.2 ms; 95%CI, -48.4 to -20.2; P = 0.004). AV nodal effective refractory period was also impaired after dexmedetomidine and showed weak evidence for return to baseline function after ketamine (mean difference between baseline and after ketamine -22.8 ms; 95%CI, -40.2 to -5.2; P = 0.069). CONCLUSION: The concurrent use of ketamine may mitigate the negative chronotropic effects of dexmedetomidine.
View details for DOI 10.1111/pan.12143
View details for PubMedID 23506472
Volatile anesthetic rescue therapy in children with acute asthma: innovative but costly or just costly?*.
Pediatric critical care medicine
2013; 14 (4): 343-350
: To describe volatile anesthesia (VA) use for pediatric asthma, including complications and outcomes.: Retrospective cohort study.: Children's hospitals contributing to the Pediatric Health Information System between 2004-2008.: Children 2-18 years old with a primary diagnosis code for asthma supported with mechanical ventilation.: Those treated with VA were compared to those not treated with VA or extracorporeal membrane oxygenation. Hospital VA use was grouped as none, <5%, 5-10% and >10% among intubated children.: One thousand five hundred and fifty-eight patients received mechanical ventilation at 40 hospitals for asthma: 47 (3%) received VA treatment at 11 (28%) hospitals. Those receiving a VA were significantly less likely to receive inhaled b-agonists, ipratropium bromide, and heliox, but more likely to receive neuromuscular blocking agents than patients treated without VA. Length of mechanical ventilation, hospital stay (length of stay [LOS]) and charges were significantly greater for those treated with VA. Aspiration was more common but death and air leak did not differ. Patients at hospitals with VA use >10% were significantly less likely to receive inhaled b agonist, ipratropium bromide, methylxanthines, and heliox, but more likely to receive systemic b agonist, neuromuscular blocking agents compared to those treated at hospitals not using VA. LOS, duration of ventilation, and hospital charges were significantly greater for patients treated at centers with high VA use.: Mortality does not differ between centers that use VA or not. Patients treated at centers with high VA use had significantly increased hospital charges and increased LOS.
View details for DOI 10.1097/PCC.0b013e3182772e29
View details for PubMedID 23439466
Case report: airway and concurrent hemodynamic management in a neonate with oculo-auriculo-vertebral (Goldenhar) syndrome, severe cervical scoliosis, interrupted aortic arch, multiple ventricular septal defects, and an unstable cervical spine
2012; 22 (9): 932-934
We report the challenging case of a 1-week-old, term, 2.4 kg neonate with Goldenhar syndrome (including microcephaly, left microtia, left facial palsy, dextro-scoliosis of the cervical spine, and cervico-thoracic levoscoliosis), multiple ventricular septal defects, a type B interrupted aortic arch, a large patent ductus arteriosis, and radiographic and clinical signs concerning for an unstable cervical spine. Our anesthesia team was consulted for perioperative management of this patient during her surgical repair. This case report describes the use of the Air-Q size 1 laryngeal airway (LA) to assist fiberoptic intubation in an ASA 4 neonate with cardiac disease, an anticipated difficult airway with the addition of an unstable cervical spine, as well as the anesthetic techniques used to maintain hemodynamic stability while the airway was secured.
View details for DOI 10.1111/j.1460-9592.2012.03915.x
View details for Web of Science ID 000306900400017
View details for PubMedID 22834469