Understanding Anti-Diuretic Hormone Dynamics in Off pump Coronary Artery Bypass Grafting (OPCABG) Patients: A Case Series
- 1Department of Anaesthesia, Mahatma Gandhi Medical College and Research Institute, Puducherry, India
- 2Department of Anaesthesiology and Pain Medicine, Mahatma Gandhi Medical College and Research Institute, Puducherry, India
- 3Department of CTVS, Mahatma Gandhi Medical College and Research Institute, Puducherry, India
Abstract
Objective(s):: The conundrum of Polyuria witnessed post-cardiac surgery has been attributed to altered antidiuretic hormone (ADH) release secondary to both osmotic and non-osmotic stimulus. This transient DI-like state is more often seen in on-bypass cardiac surgeries but a few off-bypass occurrences have also been reported. A lot of conflicting evidence has accumulated trying to explain this altered water balance but a broader conceptual framework is lacking, which we have attempted to provide, with an objective of designing a future prospective study.
Design; Setting; Participants; Interventions:: This prospective observational case-series included 12 cases, who underwent off pump coronary artery bypass grafting (OPCABG) at a single tertiary care hospital. All were operated and managed by the same anesthetist-cardiac surgeon team following a structured protocol, hence negating various confounders. Serum and urine osmolality samples were collected post-Intubation (Baseline) and within 1 hour of ICU-transfer and all relevant data associated with these cases was recorded for analysis.
Measurements and Main Results:: The data was systematically analyzed in terms of descriptives, paired T-test and correlation statistics. The pre-post serum osmolality was found to increase (P value 0.389, Cohen’s d –0.26) whereas urine osmolality decreased significantly (P value 0.013, Cohen’s d 0.85). This mean fall in urine osmolality was much higher compared to the rise seen in serum osmolality, both being negatively correlated (r –0.59, P value 0.04).
Conclusion:: This case series investigating the changes in osmolality alongside pre-perfusion reduced urine output and post-perfusion a state of polyuria, is our primer for a future assay-based objective study. We have created a framework of concepts that provide clarity to the dynamics of ADH-release in OPCABG patients. Furthermore, we are presenting a different hypothesis to explain increase in ADH-release that is evidence-based and open to critical comments.
Related
- Minimally Invasive Coronary Artery Bypass Grafting in Patients With Prior Myocardial Infarction: A Propensity Score-Matched Retrospective Study
- Effectiveness of Nursing Interventions on Stress and Functional Capacity Among Patients After Coronary Artery Bypass Grafting (CABG): A Randomized Controlled Trial
- Perioperative temporary microaxial left ventricular assist device support in patients with low ejection fraction undergoing coronary artery bypass grafting
- Association of the triglyceride-glucose index and triglyceride-glucose-body mass index with postoperative atrial fibrillation in patients undergoing off-pump coronary artery bypass grafting: a retrospective cohort study
- Influence of Perioperative Variables on Surgical Site Infection in Patients With Frailty and Prefrailty Undergoing Coronary Artery Bypass Grafting: Retrospective Multicenter Study
BibTeX
@article{dhanyee2026understanding,
title = {{Understanding Anti-Diuretic Hormone Dynamics in Off pump Coronary Artery Bypass Grafting (OPCABG) Patients: A Case Series}},
author = {Anity Singh Dhanyee and T Sivashanmugam and P Harini and V R Hemanth Kumar and S Ananthkumar},
journal = {Annals of Cardiac Anaesthesia},
year = {2026},
month = oct,
doi = {10.4103/aca.aca_294_25},
url = {https://doi.org/10.4103/aca.aca_294_25},
note = {CC BY-NC-SA 4.0},
}
RIS
TY - JOUR
TI - Understanding Anti-Diuretic Hormone Dynamics in Off pump Coronary Artery Bypass Grafting (OPCABG) Patients: A Case Series
AU - Anity Singh Dhanyee
AU - T Sivashanmugam
AU - P Harini
AU - V R Hemanth Kumar
AU - S Ananthkumar
PY - 2026
DA - 2026/10/12
JO - Annals of Cardiac Anaesthesia
DO - 10.4103/aca.aca_294_25
UR - https://doi.org/10.4103/aca.aca_294_25
AB - Objective(s):: The conundrum of Polyuria witnessed post-cardiac surgery has been attributed to altered antidiuretic hormone (ADH) release secondary to both osmotic and non-osmotic stimulus. This transient DI-like state is more often seen in on-bypass cardiac surgeries but a few off-bypass occurrences have also been reported. A lot of conflicting evidence has accumulated trying to explain this altered water balance but a broader conceptual framework is lacking, which we have attempted to provide, with an objective of designing a future prospective study. Design; Setting; Participants; Interventions:: This prospective observational case-series included 12 cases, who underwent off pump coronary artery bypass grafting (OPCABG) at a single tertiary care hospital. All were operated and managed by the same anesthetist-cardiac surgeon team following a structured protocol, hence negating various confounders. Serum and urine osmolality samples were collected post-Intubation (Baseline) and within 1 hour of ICU-transfer and all relevant data associated with these cases was recorded for analysis. Measurements and Main Results:: The data was systematically analyzed in terms of descriptives, paired T-test and correlation statistics. The pre-post serum osmolality was found to increase (P value 0.389, Cohen’s d –0.26) whereas urine osmolality decreased significantly (P value 0.013, Cohen’s d 0.85). This mean fall in urine osmolality was much higher compared to the rise seen in serum osmolality, both being negatively correlated (r –0.59, P value 0.04). Conclusion:: This case series investigating the changes in osmolality alongside pre-perfusion reduced urine output and post-perfusion a state of polyuria, is our primer for a future assay-based objective study. We have created a framework of concepts that provide clarity to the dynamics of ADH-release in OPCABG patients. Furthermore, we are presenting a different hypothesis to explain increase in ADH-release that is evidence-based and open to critical comments.
SN - 0971-9784
SN - 0974-5181
ER -