Ambulatory Care Cases: Definition and Types
Ambulatory care cases encompass all medical encounters where patients receive healthcare services without being admitted to a hospital for overnight stay, including office visits, outpatient department visits, emergency department visits where the patient is not admitted, and urgent care visits. 1
Core Categories of Ambulatory Care Encounters
Based on national surveillance data, ambulatory care visits are distributed across three primary settings 1:
- Physician office visits (82.1% of all ambulatory care)
- Emergency department visits without admission (9.9%)
- Hospital outpatient department visits (8.0%)
During 1997, there were 959.3 million ambulatory visits in the United States, representing 3.6 visits per person annually 1. This demonstrates that ambulatory care constitutes the vast majority of healthcare delivery in the United States.
Specific Types of Ambulatory Encounters
Scheduled and Routine Care
- Preventive care visits - well-child checks, routine physical examinations, immunizations
- Chronic disease management - follow-up appointments for established conditions
- Scheduled specialty consultations
Urgent and Unscheduled Care
According to ACC/AHA definitions for cardiovascular endpoints, urgent ambulatory visits are defined as unscheduled office, practice, or ED visits for a primary diagnosis where the patient is not admitted to the hospital, exhibits new or worsening symptoms, has objective evidence of the condition, and receives initiation or intensification of treatment 2. This framework, while developed for heart failure, provides a standardized approach to defining urgent ambulatory encounters.
Infection Control Context
The AAP guidelines emphasize that ambulatory settings include 3:
- Office-based physician practices
- Freestanding ambulatory facilities
- Dialysis centers
- Chemotherapy centers
- Procedure suites (endoscopy)
- Emergency centers (when no admission occurs)
- Outpatient surgery suites
Common Presenting Problems
The most frequent diagnoses in ambulatory care settings include 4:
- Musculoskeletal conditions (joint pain, lower back pain)
- Respiratory system diseases
- Mental health disorders (adjustment disorders, anxiety)
- Cardiovascular diseases
- Nervous system and sensory organ diseases
- Symptoms and ill-defined conditions
Fifteen diagnosis clusters account for 50% of all ambulatory care visits, with general and family physicians, general internists, and general pediatricians providing 65.9% of care for these common problems 4.
Key Distinguishing Features
What Separates Ambulatory from Inpatient Care
The critical distinction is that ambulatory care does not involve hospital admission with overnight stay. Even if a patient presents to an emergency department, if they are evaluated, treated, and discharged without admission (length of stay <24 hours), this constitutes an ambulatory encounter 2.
Retail Health Clinics
A newer category of ambulatory care includes retail health clinics, which should serve as episodic alternatives for relatively healthy patients without complex medical histories seeking care for simple conditions like sinusitis, urinary tract infections, and minor skin conditions 5.
Clinical Implications
Patient Flow Considerations
Ambulatory facilities must implement infection control measures starting when visits are scheduled 3. This includes:
- Telephone screening for contagious symptoms
- Separate entrances or direct examination room placement for potentially contagious patients
- Respiratory hygiene/cough etiquette protocols in waiting areas
- Maintaining 3-foot separation between symptomatic patients when feasible 3
Documentation Requirements
All ambulatory encounters require the same infection prevention and control standards as inpatient settings, including hand hygiene before and after every patient contact, appropriate use of personal protective equipment, and proper sterilization/disinfection procedures 3.
Common Pitfalls
Do not confuse ambulatory care with "outpatient care only" - emergency department visits where patients are not admitted are ambulatory encounters, even though they occur in hospital settings 1. The defining feature is the absence of hospital admission, not the physical location of care delivery.
Avoid assuming all ambulatory visits are for minor conditions - serious conditions requiring intensive treatment can be managed in ambulatory settings if hospital admission is not required 2.