UDOPAL Study: Home-Based Interventional Approach to Pain Management in Home-Hospitalized Patients

Introduction

Pain is one of the most prevalent and distressing symptoms among patients receiving home hospitalization, especially those with chronic or oncologic conditions. Despite the advances in home-based medicine, the management of moderate to severe pain continues to be a clinical challenge. Conventional pharmacological treatment alone is often insufficient, and access to specialized interventional pain techniques remains limited to hospital settings.

In traditional care models, patients experiencing uncontrolled pain must be transferred to the hospital for evaluation or intervention, leading to fragmentation of care, increased healthcare costs, and a significant emotional burden for patients and families. These transfers often disrupt the continuity of palliative and supportive care that the home-hospitalization environment seeks to provide.

The UDOPAL Study (from Unidad del Dolor + Hospitalización Domiciliaria) was designed to address this gap by introducing a structured, collaborative model that enables interventional pain management to be performed safely and effectively at home. This initiative positions home-hospital professionals at the center of the intervention, empowering them to deliver advanced pain procedures within the patient's own environment, supported by the Pain Medicine Unit when required.

The study reflects an evolution in the concept of pain management-shifting from a hospital-centered model to an integrated, patient-centered continuum of care. The UDOPAL model aligns with the principles of the World Health Organization and modern palliative medicine, emphasizing early, multidisciplinary, and accessible interventions that improve comfort, dignity, and quality of life.

Beyond clinical innovation, the UDOPAL project also represents an organizational and educational advance: it introduces a systematic training framework for home-hospital professionals to perform ultrasound-guided and minimally invasive procedures for pain control, under a protocolized supervision system. This dual focus-clinical and educational-aims to ensure safety, reproducibility, and scalability of the model.

Objectives and Hypothesis

The UDOPAL Study is based on the hypothesis that interventional pain management procedures-when adapted, standardized, and safely performed by trained Home Hospitalization Unit (UHD) professionals-can improve pain control, functionality, and patient satisfaction while optimizing healthcare resource utilization.

Primary Objective

To evaluate the feasibility and safety of performing interventional pain management techniques at home by UHD professionals within the UDOPAL model.

Secondary Objectives

To describe the prevalence and intensity of pain among patients admitted to a Home Hospitalization Unit and to determine the proportion experiencing mild, moderate, or severe pain.

To measure the reduction in opioid consumption, assessing whether improved pain control leads to decreased opioid requirements and fewer adverse effects.

To analyze the improvement in patient functionality, evaluating whether better pain management reduces physical limitations and enhances functional capacity.

To assess whether the UDOPAL model contributes to an increase in patients' quality of life.

To evaluate patient and family satisfaction with pain management and overall home-based care.

To explore the professional perception of the model's clinical impact among UHD and Pain Unit staff.

To assess the implementation of the UDOPAL model in real clinical practice, identifying facilitators and barriers to its adoption.

To analyze the healthcare demand generated by the UDOPAL model, including its influence on workload, care coordination, and service utilization.

The working hypothesis is that the UDOPAL model will demonstrate high feasibility, a favorable safety profile, and significant clinical and organizational benefits compared to conventional home-based care, contributing to a more integrated, efficient, and patient-centered approach to pain management at home.

Study Design

The UDOPAL Study is an observational, prospective study designed to evaluate the early implementation of a novel home-based model for pain management in patients admitted to the Home Hospitalization Unit (UHD). The model integrates interventional pain procedures into standard clinical practice at home, performed by UHD professionals trained in the UDOPAL protocol, with support from the Pain Medicine Unit.

The study assesses the impact of this integrated model on clinical, organizational, and perceived-quality outcomes, comparing results obtained before and after the implementation of the UDOPAL protocol. Particular attention is given to the effects of early intervention during the initial stages of clinical complexity, when timely pain control may influence the overall course of illness and quality of life.

Study Population

Adult patients (≥18 years) admitted to the Home Hospitalization Unit who present acute, chronic, or oncologic pain and may benefit from interventional pain procedures. Patients are identified by UHD professionals and managed according to the UDOPAL protocol once the intervention phase begins.

Inclusion Criteria

Patients admitted to the UHD.

Presence of acute, chronic, or oncologic pain requiring advanced pain management.

Indication for interventional pain techniques (e.g., peripheral nerve blocks, infiltrations, pulsed radiofrequency).

Ability to understand and sign informed consent (or through a legal representative).

Exclusion Criteria

Contraindication to interventional techniques (coagulopathy, local infection, allergy to local anesthetics).

Cognitive impairment or communication barrier that prevents adequate assessment.

Absence of safe or logistically feasible home environment.

Intervention and Comparison

The UDOPAL model is implemented as an early intervention protocol combining pharmacologic optimization with minimally invasive pain procedures performed at the patient's home. UHD professionals trained under the UDOPAL framework conduct the interventions using portable ultrasound guidance and aseptic technique.

The study compares two periods:

Pre-intervention phase: standard home-hospitalization care before UDOPAL implementation.

Post-intervention phase: care delivered under the UDOPAL protocol, integrating interventional pain management.

Variables and Data Collection

• Opioid Consumption [Time frame: Baseline (Day 0), 24 hours, 48 hours, 1 week, 1 month, and at discharge from the Home Hospitalization Unit (HHU)]
• Functional Status [Time frame: Baseline (Day 0), 24 hours, 48 hours, 1 week, 1 month, and at discharge from the Home Hospitalization Unit (HHU)]
• Patient and Family Satisfaction [Time frame: Baseline (Day 0), 24 hours, 48 hours, 1 week, 1 month, and at discharge from the Home Hospitalization Unit (HHU)]
• Professional Perception of Feasibility [Time frame: baseline and at completion of the implementation phase (approximately 1 month)]
• Change in Quality of Life (EQ-5D-5L Score) [Time frame: Baseline (Day 0), 24 hours, 48 hours, 1 week, 1 month, and at discharge from the Home Hospitalization Unit (HHU)]
• Change in Functional Status (Barthel Index) [Time frame: Baseline (Day 0), 24 hours, 48 hours, 1 week, 1 month, and at discharge from the Home Hospitalization Unit (HHU)]
• Change in Analgesic Consumption Profile [Time frame: Baseline (Day 0), 24 hours, 48 hours, 1 week, 1 month, and at discharge from the Home Hospitalization Unit (HHU)]
• Incidence of Adverse Events Related to Home-Based Interventional Pain Procedures [Time frame: From procedure initiation until 1 month follow-up or discharge from the Home Hospitalization Unit (HHU), whichever occurs later]
• Rate of Unplanned Hospital Transfers [Time frame: From procedure initiation until 1 month follow-up or discharge from the Home Hospitalization Unit , whichever occurs later]
• Number of Interconsultations Between the Home Hospitalization Unit and the Pain MedicineUnit [Time frame: Throughout the entire home-hospitalization episode and during the 1-month follow-up period]
• Response Time From Indication to Procedure Completion [Time frame: From clinical indication to completion of the interventional procedure (measured for each patient during the home-hospitalization episode)]
• Total Consultation Time Including Procedure Duration [Time frame: At each home visit in which an interventional pain procedure is performed]