Clinical Focus

  • Interventional Pulmonology
  • Pleural Disease
  • Rigid & Flexible Bronchoscopy
  • Robotic Bronchoscopy
  • Airway Obstruction
  • Lung Nodules
  • Pulmonary Disease
  • Critical Care Medicine

Academic Appointments

Boards, Advisory Committees, Professional Organizations

  • Member, American Association for Bronchology and Interventional Pulmonology (2020 - Present)
  • Member, American Thoracic Society (2019 - Present)
  • Member, American College of CHEST Physicians (2019 - Present)

Professional Education

  • Board Certification, American Association of Bronchology & Interventional Pulmonology, Interventional Pulmonology (2023)
  • Board Certification: American Board of Internal Medicine, Critical Care Medicine (2022)
  • Board Certification: American Board of Internal Medicine, Pulmonary Disease (2021)
  • Board Certification: American Board of Internal Medicine, Internal Medicine (2019)
  • Board Certification, American Board of Family Medicine, Family Medicine (2016)
  • Fellowship, Stanford University, Interventional Pulmonology (2023)
  • Fellowship: Loma Linda University Pulmonary and Critical Care Fellowship (2022) CA
  • Residency: Kaiser Permanente Santa Clara Internal Medicine Residency (2019) CA
  • Residency: Memorial Hospital South Bend (2016) IN
  • Medical Education: St George's University School of Medicine Grenada West Indies (2013) NY West Indies
  • BA, The University of Chicago, IL, Chemistry (2007)

All Publications

  • Unveiling the Enigma: An Intriguing Case of Endobronchial Polyp in a Post-lung Transplant Recipient Stemming From Aspiration Kang, C., Patel, P., Banga, A., Sumner, E., Cao, C. American Journal of Respiratory and Critical Care Medicine. 2024
  • Utility of multimodal sampling and testing during advanced bronchoscopy for diagnosing atypical respiratory infections in a Coccidioides-endemic region. Journal of thoracic disease Chrissian, A. A., De Silva, S., Quan, M., Wiltchik, E., Patel, P., Furukawa, B., Rogstad, D., Rockwood, N., Ho, E., Cheek, G. 2023; 15 (9): 4577-4595


    The role of advanced diagnostic bronchoscopy (ADB) for assessing atypical respiratory infections is unclear. The purpose of this study was to ascertain: (I) the diagnostic utility of ADB-tissue sampling in patients with focal thoracic lesions due to atypical respiratory infections; (II) how multimodal bronchoscopic sampling and testing enhance diagnosis in a Coccidioides-endemic region.A retrospective observational cohort study analyzing all ADBs performed over a 10-year period in patients with focal thoracic lesions diagnosed with a non-malignant disorder. Only cases which procured lower respiratory tract secretion and tissue samples by ADB, and had both cytohistology and culture results available were included.Among 403 subjects with non-malignant disease, 136 (33.7%) were diagnosed with atypical respiratory infections, with ADB contributing a diagnosis in 119 (87.5%) of these. Coccidioidal disease was independently associated with a cytohistologic diagnosis [odds ratio =7.64, 95% confidence interval (CI): 2.51-23.26; P<0.001]. Mycobacteria were more effectively identified by culture (overall yield of 8.4%, vs. 2.7% by cytohistology; P<0.001). Among subjects for which both respiratory secretion and tissue sampling were dual-tested with culture and cytology/cytohistology, adding ADB-guided transbronchial needle aspiration and/or forceps biopsy (TBNA/TBFB) to bronchoalveolar lavage and/or bronchial washings (BAL/BW) more than doubled the yield for dimorphic fungi, from 7.1% to 15.1% (increase of 8.0%, 95% CI: 5.2-11.9%). For lung lesions, adding tissue culture to dual TBNA/TBFB cytohistology-tested lung samples doubled the proportion diagnosed with atypical infection over using TBNA-cytohistology alone (increase of 15.8%, 95% CI: 10.4-23.1%). Adding lymph node to lung sampling increased the proportion diagnosed with coccidioidomycosis by 8.8% (95% CI: 4.8-15%). Among subjects with atypical respiratory infections, major ADB-related complications occurred in 1.5%.ADB is useful for diagnosing atypical respiratory infections manifesting as focal thoracic lesions. A multimodal approach to both sampling and testing enhances yield, while maintaining a favorable procedure safety profile. Cytohistology testing and nodal sampling are beneficial for pulmonary coccidioidomycosis, and culture for mycobacterial disease. The approach to ADB-sampling should be adjusted according to clinical context and regional infection patterns.

    View details for DOI 10.21037/jtd-23-83

    View details for PubMedID 37868856

    View details for PubMedCentralID PMC10586940

  • Original Research: COVID-19 Vaccine Hesitancy Among Southern California Nurses AMERICAN JOURNAL OF NURSING Roberts, L. R., Dubov, A., Distelberg, B., Peteet, B., Abdul-Mutakabbir, J. C., Montgomery, S., Patel, P., Chrissian, A. A. 2022; 122 (11): 22-31


    The purpose of this study was to elucidate characteristics of vaccine-hesitant nurses at two large Southern California medical centers where rates of COVID-19 vaccination were lower than expected.This study is a secondary analysis of nurse participants in a cross-sectional study conducted at the two medical centers. Participants completed an online survey regarding their demographics; work setting and role characteristics; influenza vaccination history; COVID-19 knowledge and beliefs; and personal history of COVID-19 exposure, diagnosis, and disease impact (infection or death) on those closest to them.Of 869 nurse participants, most (78.6%) were vaccinated and 21.4% were unvaccinated; more than half of the unvaccinated participants reported being unwilling to be vaccinated ("vaccine hesitant"). The χ 2 comparisons revealed no significant differences between vaccinated and vaccine-hesitant nurses in terms of education, contact with COVID-19 patients, work environment, or having friends and family impacted by COVID-19. Binary logistic regression showed that nurses who had no history of recent influenza vaccination were 10 times more likely to be vaccine hesitant, those who had inaccurate knowledge about COVID-19 vaccines were seven times more likely to be vaccine hesitant, and younger nurses and those with a prior COVID-19 diagnosis were approximately three times more likely to be vaccine hesitant. Furthermore, 17.3% of all participants were unwilling to recommend COVID-19 vaccination to others.The findings offer a nuanced understanding of vaccine hesitancy among nurses and will be useful to the planning and development of policies, campaigns, and interventions aimed at increasing vaccination rates among nurses. Changing attitudes is essential, and particular attention must be paid to nurses who are unwilling to recommend vaccination to others. Effective interventions are needed.

    View details for DOI 10.1097/01.NAJ.0000892492.43587.5f

    View details for Web of Science ID 000870054000015

    View details for PubMedID 36201394

  • Racial/Ethnic Variances in COVID-19 Inoculation among Southern California Healthcare Workers VACCINES Dubov, A., Distelberg, B. J., Abdul-Mutakabbir, J. C., Peteet, B., Roberts, L., Montgomery, S. B., Rockwood, N., Patel, P., Shoptaw, S., Chrissian, A. A. 2022; 10 (8)


    Healthcare workers (HCWs) from minoritized communities are a critical partner in moving vaccine-hesitant populations toward vaccination, yet a significant number of these HCWs are delaying or deciding against their own COVID-19 vaccinations. Our study aims to provide a more nuanced understanding of vaccine hesitancy among racially and ethnically minoritized HCWs and to describe factors associated with vaccine non-acceptance. Analysis of a sub-sample of racially and ethnically minoritized HCWs (N = 1131), who participated in a cross-sectional study at two large Southern California medical centers, was conducted. Participants completed an online survey consisting of demographics, work setting and clinical role, influenza vaccination history, COVID-19 knowledge, beliefs, personal COVID-19 exposure, diagnosis, and impact on those closest to them. While overall most HCWs were vaccinated (84%), 28% of Black, 19% of Hispanic, and 8% of Asian American HCWs were vaccine-hesitant. Age, education level, occupation, history of COVID-19, and COVID-19 related knowledge were predictive of vaccine hesitancy. We found significant variations in COVID-19 related knowledge and reasons for vaccine hesitancy among Black (governmental mistrust), Hispanic (preference for physiological immunity), and Asian-American HCWs (concern about side effects) who were vaccine-hesitant or not. Our findings highlight racial and ethnic differences in vaccine-hesitancy and barriers to vaccination among HCWs of color. This study indicates the necessity of targeted interventions to reduce vaccine hesitancy that are mindful of the disparities in knowledge and access and differences between and among racial and ethnic groups.

    View details for DOI 10.3390/vaccines10081331

    View details for Web of Science ID 000845132900001

    View details for PubMedID 36016219

    View details for PubMedCentralID PMC9414471

  • Impact of COVID-19 vaccine-associated side effects on health care worker absenteeism and future booster vaccination. Vaccine Chrissian, A. A., Oyoyo, U. E., Patel, P., Lawrence Beeson, W., Loo, L. K., Tavakoli, S., Dubov, A. 2022


    Short-term side effects related to mRNA vaccines against SARS-CoV-2 are frequent and bothersome, with the potential to disrupt work duties and impact future vaccine decision-making.To identify factors more likely to lead to vaccine-associated work disruption, employee absenteeism, and future vaccine reluctance among healthcare workers (HCWs).Side effects related to COVID vaccination: 1- frequently disrupt HCW duties, 2- result in a significant proportion of HCW absenteeism, 3- contribute to uncertainty about future booster vaccination, 4- vary based on certain demographic, socioeconomic, occupational, and vaccine-related factors.Using an anonymous, voluntary electronic survey, we obtained responses from a large, heterogeneous sample of COVID-19-vaccinated HCWs in two healthcare systems in Southern California. Descriptive statistics and regression models were utilized to evaluate the research questions.Among 2,103 vaccinated HCWs, 579 (27.5%) reported that vaccine-related symptoms disrupted their professional responsibilities, and 380 (18.1%) missed work as a result. Independent predictors for absenteeism included experiencing generalized and work-disruptive symptoms, and receiving the Moderna vaccine [OR = 1.77 (95% CI = 1.33 - 2.36), p < 0.001]. Physicians were less likely to miss work due to side effects (6.7% vs 21.2% for all other HCWs, p < 0.001). Independent predictors of reluctance toward future booster vaccination included lower education level, younger age, having received the Moderna vaccine, and missing work due to vaccine-related symptoms.Symptoms related to mRNA vaccinations against SARS-CoV-2 may frequently disrupt work duties, lead to absenteeism, and impact future vaccine decision-making. This may be more common in Moderna recipients and less likely among physicians. Accordingly, health employers should schedule future booster vaccination cycles to minimize loss of work productivity.

    View details for DOI 10.1016/j.vaccine.2022.04.046

    View details for PubMedID 35465979

    View details for PubMedCentralID PMC9013647

  • PREVALENCE AND CHARACTERISTICS OF MEMORY DEFICITS IN COVID-19 SURVIVORS Grewal, S., Alismail, A., Kim, V., Monterroso, P., Arias, C., Patel, P., Jeganathan, N. Critical Care Medicine. 2022
  • Predictors of COVID-19 Vaccine Acceptance and Hesitancy among Healthcare Workers in Southern California: Not Just "Anti" vs. "Pro" Vaccine. Vaccines Dubov, A., Distelberg, B. J., Abdul-Mutakabbir, J. C., Beeson, W. L., Loo, L. K., Montgomery, S. B., Oyoyo, U. E., Patel, P., Peteet, B., Shoptaw, S., Tavakoli, S., Chrissian, A. A. 2021; 9 (12)


    In this study, we evaluated the status of and attitudes toward COVID-19 vaccination of healthcare workers in two major hospital systems (academic and private) in Southern California. Responses were collected via an anonymous and voluntary survey from a total of 2491 participants, including nurses, physicians, other allied health professionals, and administrators. Among the 2491 participants that had been offered the vaccine at the time of the study, 2103 (84%) were vaccinated. The bulk of the participants were middle-aged college-educated White (73%), non-Hispanic women (77%), and nursing was the most represented medical occupation (35%). Political affiliation, education level, and income were shown to be significant factors associated with vaccination status. Our data suggest that the current allocation of healthcare workers into dichotomous groups such as "anti-vaccine vs. pro-vaccine" may be inadequate in accurately tailoring vaccine uptake interventions. We found that healthcare workers that have yet to receive the COVID-19 vaccine likely belong to one of four categories: the misinformed, the undecided, the uninformed, or the unconcerned. This diversity in vaccine hesitancy among healthcare workers highlights the importance of targeted intervention to increase vaccine confidence. Regardless of governmental vaccine mandates, addressing the root causes contributing to vaccine hesitancy continues to be of utmost importance.

    View details for DOI 10.3390/vaccines9121428

    View details for PubMedID 34960171

    View details for PubMedCentralID PMC8706436