Patricia Garcia, MD is a board certified gastroenterologist and fellowship trained neurogastroenterologist who specializes in treating disorders of gastrointestinal motility including trouble swallowing, heartburn, reflux, constipation, fecal incontinence and pelvic floor dysfunction.
- Neurogastroenterology and Motility
Clinical Associate Professor, Medicine - Gastroenterology & Hepatology
Associate Clinical Information Officer, Ambulatory Care, Stanford Health Care (2022 - Present)
Director, GI Motility Laboratory, Stanford Digestive Health Center (2018 - Present)
Boards, Advisory Committees, Professional Organizations
Member, American Neurogastroenterolgy and Motility Society (2014 - Present)
Member, American Gastroenterology Association (2011 - Present)
Member, American College of Gastroenterology (2011 - Present)
Fellowship, Johns Hopkins University, Neurogastroenterology and Motility (2015)
Board Certification: American Board of Internal Medicine, Gastroenterology (2014)
Fellowship: New York Presbyterian Hospital of Columbia and Cornell Universities (2014) NY
Board Certification: American Board of Internal Medicine, Internal Medicine (2011)
Residency: University of Pennsylvania Health System (2011) PA
Medical Education: University of Michigan Medical School (2008) MI
Development and Validation of a Machine Learning System to Identify Reflux Events in Esophageal 24-hour pH/Impedance Studies.
Clinical and translational gastroenterology
INTRODUCTION: Esophageal 24-hour pH/impedance testing is routinely performed to diagnose gastroesophageal reflux disease (GERD). Interpretation of these studies is time-intensive for expert physicians and has high inter-reader variability. There are no commercially available machine learning tools to assist with automated identification of reflux events in these studies.METHODS: A machine learning system to identify reflux events in 24-hour pH/impedance studies was developed, which included an initial signal processing step and a machine learning model. Gold standard reflux events were defined by a group of expert physicians. Performance metrics were computed to compare the machine learning system, current automated detection software (Reflux Reader v6.1), and an expert physician reader.RESULTS: The study cohort included 45 patients (20/5/20 patients in the training/validation/test sets, respectively). Mean age was 51 (standard deviation [SD] 14.5) years, 47% of patients were male, and 78% of studies were performed off proton pump inhibitor (PPI). Comparing the machine learning system vs. current automated software vs. expert physician reader, AUC was 0.87 (95% CI 0.85-0.89) vs. 0.40 (95% CI 0.37-0.42) vs. 0.83 (95% CI 0.81-0.86), respectively; sensitivity was 68.7% vs. 61.1% vs. 79.4%, respectively; and specificity was 80.8% vs. 18.6% vs. 87.3%, respectively.DISCUSSION: We trained and validated a novel machine learning system to successfully identify reflux events in 24-hour pH/impedance studies. Our model performance was superior to that of existing software and comparable to that of a human reader. Machine learning tools could significantly improve automated interpretation of pH/impedance studies.
View details for DOI 10.14309/ctg.0000000000000634
View details for PubMedID 37578060
Differential Findings on Anorectal Manometry in Patients with Parkinson's Disease and Defecatory Dysfunction.
Movement disorders clinical practice
2023; 10 (7): 1074-1081
Gastrointestinal dysfunction, particularly constipation, is among the most common non-motor manifestations in Parkinson's Disease (PD). We aimed to identify high-resolution anorectal manometry (HR-ARM) abnormalities in patients with PD using the London Classification.We conducted a retrospective review of all PD patients at our institution who underwent HR-ARM and balloon expulsion test (BET) for evaluation of constipation between 2015 and 2021. Using age and sex-specific normal values, HR-ARM recordings were re-analyzed and abnormalities were reported using the London Classification. A combination of Wilcoxon rank sum and Fisher's exact test were used.36 patients (19 women) with median age 71 (interquartile range [IQR]: 69-74) years, were included. Using the London Classification, 7 (19%) patients had anal hypotension, 17 (47%) had anal hypocontractility, and 3 women had combined hypotension and hypocontractility. Anal hypocontractility was significantly more common in women compared to men. Abnormal BET and dyssynergia were noted in 22 (61%) patients, while abnormal BET and poor propulsion were only seen in 2 (5%). Men had significantly more paradoxical anal contraction and higher residual anal pressures during simulated defecation, resulting in more negative recto-anal pressure gradients. Rectal hyposensitivity was seen in nearly one third of PD patients and comparable among men and women.Our data affirms the high prevalence of anorectal disorders in PD. Using the London Classification, abnormal expulsion and dyssynergia and anal hypocontractility were the most common findings in PD. Whether the high prevalence of anal hypocontractility in females is directly related to PD or other confounding factors will require further research.
View details for DOI 10.1002/mdc3.13755
View details for PubMedID 37476327
View details for PubMedCentralID PMC10354598
- Differential Findings on Anorectal Manometry in Patients with Parkinson's Disease and Defecatory Dysfunction MOVEMENT DISORDERS CLINICAL PRACTICE 2023
The Impact of Intermittent Fasting on Patients With Suspected Gastroesophageal Reflux Disease.
Journal of clinical gastroenterology
GOAL: The aim was to investigate the short-term impact of time restricted feeding on patients with suspected gastroesophageal reflux disease (GERD).BACKGROUND: Lifestyle modifications are often suggested, but the role of diet in GERD is unclear. Intermittent fasting is popular in the media and has demonstrated potential benefits with weight loss and inflammatory conditions as well as alterations in gastrointestinal hormones.STUDY: Patients who were referred for 96-hour ambulatory wireless pH monitoring off proton pump inhibitor to investigate GERD symptoms were screened for eligibility. Patients were instructed to maintain their baseline diet for the first 2 days of pH monitoring and switch to an intermittent fasting regimen (16 consecutive hour fast and 8h eating window) for the second 2 days. Objective measures of reflux and GERD symptom severity were collected and analyzed.RESULTS: A total of 25 participants were analyzed. 9/25 (36%) fully adhered to the intermittent fasting regimen, with 21/25 (84%) demonstrating at least partial compliance. Mean acid exposure time on fasting days was 3.5% versus 4.3% on nonfasting days. Intermittent fasting was associated with a 0.64 reduction in acid exposure time (95% CI: -2.32, 1.05). There was a reduction in GERD symptom scores of heartburn and regurgitation during periods of intermittent fasting (14.3 vs. 9.9; difference of -4.46, 95% CI: -7.6,-1.32).CONCLUSIONS: Initial adherence to time restricted eating may be difficult for patients. There is weak statistical evidence to suggest that intermittent fasting mildly reduces acid exposure. Our data show that short-term intermittent fasting improves symptoms of both regurgitation and heartburn.
View details for DOI 10.1097/MCG.0000000000001788
View details for PubMedID 36730832
Marijuana, Ondansetron, and Promethazine Are Perceived as Most Effective Treatments for Gastrointestinal Nausea.
Digestive diseases and sciences
BACKGROUND: Many anti-nausea treatments are available for chronic gastrointestinal syndromes, but data on efficacy and comparative effectiveness are sparse.AIMS: To conduct a sectional survey study of patients with chronic nausea to assess comparative effectiveness of commonly used anti-nausea treatments.METHODS: Outpatients at a single center presenting for gastroenterology evaluation were asked to rate anti-nausea efficacy on a scale of 0 (no efficacy) to 5 (very effective) of 29 commonly used anti-nausea treatments and provide other information about their symptoms. Additional information was collected from the patients' chart. The primary outcome was to determine which treatments were better or worse than average using a t test. The secondary outcome was to assess differential response by individual patient characteristics using multiple linear regression.RESULTS: One hundred and fifty-three patients completed the survey. The mean efficacy score of all anti-nausea treatments evaluated was 1.73. After adjustment, three treatments had scores statically higher than the mean, including marijuana (2.75, p<0.0001), ondansetron (2.64, p<0.0001), and promethazine (2.46, p<0.0001). Several treatments, including many neuromodulators, complementary and alternative treatments, erythromycin, and diphenhydramine had scores statistically below average. Patients with more severe nausea responded better to marijuana (p=0.036) and diphenhydramine (p<0.001) and less so to metoclopramide (p=0.020). There was otherwise no significant differential response by age, gender, nausea localization, underlying gastrointestinal cause of nausea, and GCSI.CONCLUSIONS: When treating nausea in patients with chronic gastrointestinal syndromes, clinicians may consider trying higher performing treatments first, and forgoing lower performing treatments. Further prospective research is needed, particularly with respect to highly effective treatments.
View details for DOI 10.1007/s10620-020-06195-5
View details for PubMedID 32185665
- Recurrent Small Bowel Obstruction with Intraluminal Structures. The journal of trauma and acute care surgery 2020
- Gastric per-oral endoscopic myotomy: Current status and future directions WORLD JOURNAL OF GASTROENTEROLOGY 2019; 25 (21): 2581–90
- Under Pressure: Do Volume-Based Measurements Define Rectal Hyposensitivity in Clinical Practice? DIGESTIVE DISEASES AND SCIENCES 2019; 64 (5): 1062–63
REFRACTORY GASTROPARESIS: GASTRIC PERORAL ENDOSCOPIC MYOTOMY (G-POEM) VS. INTRAPYLORIC BOTULINUM TOXIN INJECTION
MOSBY-ELSEVIER. 2018: AB241–AB242
View details for Web of Science ID 000434248200406