Clinical Focus

  • Anesthesia

Academic Appointments

Professional Education

  • Board Certification: National Board of Echocardiography, Basic Perioperative Transesophageal Echocardiography (2018)
  • Board Certification: American Board of Anesthesiology, Anesthesia (2021)
  • Board Certification: American Board of Anesthesiology, Critical Care Medicine (2021)
  • Board Certification: American Board of Internal Medicine, Internal Medicine (2019)
  • Fellowship: Stanford University Critical Care Medicine Fellowship (2020) CA
  • Residency: Stanford University Anesthesiology Residency (2019) CA
  • Residency, Stanford University Internal Medicine (2019)
  • Internship: Stanford University Internal Medicine Residency (2015) CA
  • Medical Education: University of Wisconsin SOM and Public Health (2014) WI

All Publications

  • Effect of Enteral Guanfacine on Dexmedetomidine Use in the ICU. Critical care explorations Fetters, M. B., Diep, C., Ran, R., Kloosterboer, A. 2022; 4 (11): e0785


    Describe the efficacy and safety of guanfacine for dexmedetomidine weaning in critically ill patients.DESIGN: Retrospective descriptive analysis.SETTING: Six hundred thirteen-bed academic medical center from October 2020 to October 2021.PATIENT/SUBJECTS: All Adult patients on IV dexmedetomidine who received at least one dose of guanfacine for sedation or agitation were included.INTERVENTIONS: Enteral guanfacine.MEASUREMENTS AND MAIN RESULTS: The primary outcome was discontinuation of dexmedetomidine therapy within 48 hours after guanfacine initiation. Secondary outcomes assessed included adjunctive medication use, rate of dexmedetomidine reinitiation, and safety outcomes. One hundred five patients were included in the analysis. Median age was 59 years old, 66% were male, and median daily dose of guanfacine was 1.5mg. Dexmedetomidine was discontinued within 48 hours in 58% of patients (n = 61) and within 72 hours in 71% of patients (n = 75). Fifty-five percent of patients (n = 58) required rescue medications for poorly controlled agitation, sedation, or pain while on guanfacine. Dexmedetomidine withdrawal occurred in 2% of patients (n = 2) while on guanfacine. Adverse effects attributed to guanfacine occurred in 8% of patients (n = 8), all experiencing hypotension leading to medication discontinuation.CONCLUSION: Dexmedetomidine was successfully weaned within 48 hours of guanfacine initiation in 58% of patients with minimal withdrawal or adverse effects. Guanfacine may be an effective and safe enteral option for dexmedetomidine weaning in critically ill patients.

    View details for DOI 10.1097/CCE.0000000000000785

    View details for PubMedID 36349291

  • Beyond the ventilator-cardiovascular management in SARS-CoV-2 infection INDIAN JOURNAL OF RESPIRATORY CARE Kloosterboer, A. L., Vogelsong, M. A., Brodt, J. L. 2021; 10: 43-49
  • Catecholamine-induced cerebral vasospasm and multifocal infarctions in pheochromocytoma. Endocrinology, diabetes & metabolism case reports Madhok, J. n., Kloosterboer, A. n., Venkatasubramanian, C. n., Mihm, F. G. 2020; 2020


    We report the case of a 76-year-old male with a remote history of papillary thyroid cancer who developed severe paroxysmal headaches in the setting of episodic hypertension. Brain imaging revealed multiple lesions, initially of inconclusive etiology, but suspicious for metastatic foci. A search for the primary malignancy revealed an adrenal tumor, and biochemical testing confirmed the diagnosis of a norepinephrine-secreting pheochromocytoma. Serial imaging demonstrated multiple cerebral infarctions of varying ages, evidence of vessel narrowing and irregularities in the anterior and posterior circulations, and hypoperfusion in watershed areas. An exhaustive work-up for other etiologies of stroke including thromboembolic causes or vasculitis was unremarkable. There was resolution of symptoms, absence of new infarctions, and improvement in vessel caliber after adequate alpha-adrenergic receptor blockade for the management of pheochromocytoma. This clinicoradiologic constellation of findings suggested that the etiology of the multiple infarctions was reversible cerebral vasoconstriction syndrome (RCVS). Pheochromocytoma remains a poorly recognized cause of RCVS. Unexplained multifocal cerebral infarctions in the setting of severe hypertension should prompt the consideration of a vasoactive tumor as the driver of cerebrovascular dysfunction. A missed or delayed diagnosis has the potential for serious neurologic morbidity for an otherwise treatable condition.The constellation of multifocal watershed cerebral infarctions of uncertain etiology in a patient with malignant hypertension should trigger the consideration of undiagnosed catecholamine secreting tumors, such as pheochromocytomas and paragangliomas. Reversible cerebral vasoconstriction syndrome is a serious but reversible cerebrovascular manifestation of pheochromocytomas that may lead to strokes (ischemic and hemorrhagic), seizures, and cerebral edema. Alpha-adrenergic receptor blockade can reverse cerebral vasoconstriction and prevent further cerebral ischemia and infarctions. Early diagnosis of catecholamine secreting tumors has the potential for reducing neurologic morbidity and mortality in patients presenting with cerebrovascular complications.

    View details for DOI 10.1530/EDM-20-0078

    View details for PubMedID 32820130

  • Palliative Care Opportunities Among Adults with Congenital Heart Disease - A Systematic Review. Journal of pain and symptom management Ludmir, J., Steiner, J. M., Wong, H., Kloosterboer, A., Leong, J., Aslakson, R. A. 2019


    CONTEXT: Little is known about advance care planning (ACP) and palliative care needs among adults with congenital heart disease (ACHD).OBJECTIVES: To identify and synthesize studies concerning palliative care among ACHD patients.METHODS: We searched five electronic databases (PubMed, Embase, SCOPUS, Web of Science, and CINAHL) using the keywords palliative care and congenital heart disease. Inclusion criteria were adults (age >18) with congenital heart disease and publications in English through March 3, 2019.RESULTS: Our search yielded 2872 studies, and after removal of duplicates, we screened 2319 abstracts and identified 7 for inclusion. Study findings were grouped into three domains: ACP, symptomatology, and End-of-Life care. Among the 5 cross-sectional studies, only 1-28% of ACHD patients recalled participating in ACP discussions with their doctors but 69-78% reported a strong interest and desire to participate in ACP. In one study, 46% (n=67) of patients had elevated anxiety symptoms (Hospital Anxiety and Depression Scale (HADS-A) ≥ 8) and 11% (n=15) had elevated depressive symptoms (HADS-A ≥ 8). ACHD patients who had a documented goals of care conversation prior to cardiac decompensation had a lower incidence of resuscitation and aggressive treatments at end-of-life (12% (n=3) vs 100% (n=12), p<0.001).CONCLUSION: While few ACHD patients complete advance directives, our findings support that many ACHD patients recognize the value of initiating end-of-life and goals of care conversations early on in the course of illness. Future studies investigating communication and implementation strategies of ACP as well as the symptom experience of patients with ACHD are needed.

    View details for DOI 10.1016/j.jpainsymman.2019.07.025

    View details for PubMedID 31404639