P-POSSUM for Outcomes After Abdominal Surgery (PPOSSUM-ABD)

Postoperative complications after abdominal surgery can lead to prolonged recovery, intensive care admission, and death. The P-POSSUM score is a commonly used surgical risk prediction tool, but its performance may vary between hospitals and patient populations. Frailty, especially in older patients, may also affect postoperative outcomes and may improve risk prediction when added to existing scoring systems.

This ambispective observational cohort study evaluates the prognostic value of the P-POSSUM score, with additional assessment of frailty and routine perioperative clinical data, for predicting postoperative complications and treatment outcomes in adult patients undergoing abdominal surgery at Bach Mai Hospital. The study includes retrospective data from January 2025 and prospective data collection through May 2026. No intervention is assigned by the investigators. All patients receive routine perioperative care according to clinical practice.

The study will assess the predictive performance of P-POSSUM for postoperative complications and mortality, and will explore whether adding frailty-related variables improves risk prediction.

Study Overview

• Status: Active, not recruiting
• Conditions: Postoperative Complications; Frailty; Abdominal Surgery; Postoperative Mortality; Surgical Risk Prediction

Detailed Description

Postoperative complications remain an important cause of morbidity, prolonged hospital stay, intensive care use, and mortality after abdominal surgery. Risk prediction before and after surgery may help clinicians identify high-risk patients, guide perioperative planning, and improve postoperative monitoring. The Portsmouth Physiological and Operative Severity Score for the Enumeration of Mortality and Morbidity, known as P-POSSUM, combines physiological and operative variables to estimate the risk of postoperative morbidity and mortality. However, the performance of P-POSSUM may differ across populations, surgical settings, and healthcare systems.

Frailty is increasingly recognized as an important predictor of adverse postoperative outcomes, particularly in older surgical patients. Frailty reflects reduced physiological reserve and increased vulnerability to acute stressors such as emergency surgery, infection, bleeding, and postoperative critical illness. In this study, frailty will be assessed using routinely available clinical information. For retrospective data, frailty-related status will be evaluated using available medical records and a modified frailty index when sufficient data are available. For prospectively enrolled patients, frailty will be assessed based on baseline functional status before the acute surgical illness, using a standardized clinical frailty assessment when feasible.

This study is designed as an ambispective observational cohort study conducted at the Center for Anesthesia and Surgical Intensive Care, Bach Mai Hospital, Vietnam. The study includes retrospective data from patients undergoing abdominal surgery from January 2025 and prospective data collection through May 2026. Eligible adult patients undergoing abdominal surgery will be included according to predefined selection criteria. The investigators will not assign any intervention or modify treatment decisions. Perioperative management, surgical care, anesthesia, postoperative monitoring, and intensive care treatment will be provided according to routine clinical practice.

For each eligible patient, demographic characteristics, comorbidities, physiological variables, operative severity variables, frailty-related variables, perioperative laboratory results, anesthesia and surgical information, postoperative complications, and treatment outcomes will be collected. The P-POSSUM score will be calculated using the predefined physiological and operative scoring components. Study outcomes will be obtained from hospital medical records, anesthesia records, surgical records, intensive care charts, laboratory data, and discharge documentation.

The primary objective is to evaluate the prognostic performance of P-POSSUM for postoperative complications after abdominal surgery. Secondary objectives include evaluating the performance of P-POSSUM for postoperative mortality and other treatment outcomes, assessing calibration and discrimination of the score, and exploring whether the addition of frailty-related variables and routinely available perioperative data improves risk prediction compared with P-POSSUM alone.

• Study Type: Observational
• Enrollment (Estimated): 3000

Contacts and Locations

Study Locations

• Vietnam
  • Hanoi
    • Hanoi, Hanoi, Vietnam, 00000
      • Bach Mai Hospital, Hanoi, Viet Nam.

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Older adult patients aged 60 years or older undergoing abdominal surgery at Bach Mai Hospital. The study population includes patients identified from retrospective hospital records from January 2025 and prospectively collected data through May 2026. P-POSSUM variables, frailty-related variables, routine perioperative clinical data, postoperative complications, and treatment outcomes will be collected for prognostic evaluation.

Description

Inclusion Criteria:

Patients aged 60 years or older. Patients undergoing abdominal surgery at Bach Mai Hospital. Patients managed perioperatively or postoperatively by the Center for Anesthesia and Surgical Intensive Care.

Patients with available perioperative clinical data required to calculate the P-POSSUM score.

Patients with available baseline clinical, comorbidity, or functional status information for frailty assessment.

Patients with available postoperative outcome data for assessment of complications, mortality, or treatment outcomes.

Exclusion Criteria:

Patients younger than 60 years. Patients not undergoing abdominal surgery. Patients undergoing minor procedures without operative severity data required for P-POSSUM calculation.

Patients with missing key physiological or operative variables required to calculate the P-POSSUM score.

Patients with insufficient baseline information for frailty assessment. Patients with insufficient postoperative follow-up data for outcome assessment.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Abdominal Surgery Cohort; Adult patients undergoing abdominal surgery at Bach Mai Hospital who meet the study eligibility criteria. Participants will be identified from retrospective records from January 2025 and prospectively collected data through May 2026. No intervention will be assigned by the investigators. P-POSSUM physiological and operative variables, frailty-related variables, routine perioperative clinical data, postoperative complications, and treatment outcomes will be collected to evaluate prognostic performance and risk prediction.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of patients with postoperative complications within 30 days after abdominal surgery	The proportion of patients who develop one or more postoperative complications after abdominal surgery. Postoperative complications include surgical, infectious, respiratory, cardiovascular, renal, neurological, bleeding-related, or other clinically documented complications requiring treatment, monitoring, ICU care, reoperation, or other medical intervention. Complications will be identified from anesthesia records, surgical records, ICU charts, laboratory and imaging results, discharge summaries, and hospital medical records. This outcome will be used to evaluate the prognostic performance of P-POSSUM and frailty-enhanced risk prediction.	Within 30 days after surgery or until hospital discharge, whichever occurs first

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
All-cause mortality within 30 days after abdominal surgery	All-cause mortality after abdominal surgery will be recorded from hospital medical records, ICU records, discharge documentation, and follow-up information when available. This outcome will be used to assess the prognostic performance of P-POSSUM and frailty-related variables for postoperative mortality.	Within 30 days after surgery or until hospital discharge, whichever occurs first
Discrimination of P-POSSUM for postoperative complications	The discrimination of the P-POSSUM score for postoperative complications will be assessed using the area under the receiver operating characteristic curve. The area under the receiver operating characteristic curve will be reported as a single unitless measure, calculated for postoperative complications occurring within 30 days after surgery or before hospital discharge, whichever occurs first.	Postoperative complications occurring from the end of surgery through 30 days after surgery or hospital discharge, whichever occurs first.
Incremental discrimination of frailty-related variables added to P-POSSUM	The incremental predictive value of frailty-related variables added to the P-POSSUM score will be assessed by the change in area under the receiver operating characteristic curve between the model including P-POSSUM alone and the model including P-POSSUM plus frailty-related variables. The change in area under the receiver operating characteristic curve will be reported as a single unitless measure.	Postoperative complications occurring from the end of surgery through 30 days after surgery or hospital discharge, whichever occurs first.
Intensive care unit length of stay	Intensive care unit length of stay will be reported as a single continuous measure in days. It will be calculated from the recorded date and time of ICU admission to the recorded date and time of ICU discharge or death, whichever occurs first, using ICU charts and hospital medical records.	From ICU admission until ICU discharge or death, assessed up to 30 days after ICU admission.
Hospital length of stay	Hospital length of stay will be reported as a single continuous measure in days. It will be calculated from the date of hospital admission to the date of hospital discharge or in-hospital death, whichever occurs first, using hospital administrative records and discharge documentation.	From hospital admission until hospital discharge or in-hospital death, assessed up to 90 days after hospital admission.

Collaborators and Investigators

• Sponsor: Bach Mai Hospital

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2026
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): June 30, 2026

Study Registration Dates

• First Submitted: June 16, 2026
• First Submitted That Met QC Criteria: June 21, 2026
• First Posted (Actual): June 25, 2026

Study Record Updates

• Last Update Posted (Actual): June 25, 2026
• Last Update Submitted That Met QC Criteria: June 21, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Abdominal surgery; Prognostic score; Clinical Frailty Scale; P-POSSUM; Modified Frailty Index; Perioperative risk assessment
• Additional Relevant MeSH Terms: Pathologic Processes; Pathological Conditions, Signs and Symptoms; Frailty; Postoperative Complications
• Other Study ID Numbers: BM_2026_161

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual participant data underlying the main published results may be shared upon reasonable request. Shared data may include baseline demographic and clinical characteristics, P-POSSUM physiological and operative variables, frailty-related variables, routine perioperative data, postoperative complications, mortality, length of stay, and other treatment outcomes used in the final analysis. No directly identifiable participant information will be shared.
• IPD Sharing Time Frame: De-identified individual participant data and supporting documents will be available after publication of the main study results. There is no predetermined end date for data availability; requests will be considered according to institutional policies, ethics requirements, and data sharing agreements.
• IPD Sharing Access Criteria: Data may be shared with qualified researchers for systematic reviews, meta-analyses, external validation, or scientifically valid secondary analyses. Access will require submission of a research proposal, approval by an ethics committee when applicable, and a signed data sharing agreement with the study custodian or sponsor. Requests should be sent to the study contact. Shared data will be de-identified and limited to variables necessary for the approved analysis.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ANALYTIC_CODE

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No