Critically ill patients admitted to intensive care units (ICUs) often face complex pathophysiological disturbances, among which electrolyte imbalances, particularly hypokalaemia, remain a significant concern. Potassium plays an essential role in maintaining cellular membrane potential and neuromuscular function, and its deficiency can precipitate life-threatening arrhythmias, especially in vulnerable ICU populations. Managing potassium levels thus becomes a priority in critical care settings, yet there remains clinical uncertainty around the optimal strategy for replacement—whether aggressive correction is beneficial or fraught with risk compared to more conservative approaches [1].

Potassium disturbances often occur alongside other metabolic derangements, such as hyperglycemia, acidosis, and fluid overload, which are common in critically ill patients suffering from sepsis, trauma, or renal dysfunction. Evidence suggests that aggressive fluid and electrolyte correction strategies can have unintended systemic consequences, including cellular oedema and impaired organ function [2]. This is particularly pertinent in the context of ICU-based renal replacement therapy, where the balance between therapeutic benefit and iatrogenic harm is delicate [3].

Hypokalaemia frequently coexists with hyperglycemia in critically ill patients, such as those experiencing diabetic ketoacidosis or hyperosmolar hyperglycemic states, necessitating concurrent management of glucose and potassium [4]. Improper management of either element may worsen clinical outcomes, particularly in patients with underlying endocrine disturbances. Studies have linked poor glucose control to increased ICU mortality [5], further emphasizing the need for a balanced, integrated approach to potassium correction in such scenarios.

Excess fluid administration, often accompanying aggressive resuscitative protocols, can independently increase ICU morbidity and length of stay [6]. Recent insights underscore the importance of fluid stewardship, cautioning against overzealous correction strategies that fail to account for evolving patient physiology and risk of volume overload [7].

Despite these concerns, few prospective studies have directly compared aggressive versus conservative potassium replacement strategies in ICU settings. This gap is especially pronounced in resource-limited environments, where treatment approaches often rely on institutional norms rather than standardized protocols. Recognizing this clinical gap, the present prospective observational study conducted at Sukh Sagar Medical College and Hospital (SSMCH), Jabalpur, aims to evaluate the clinical outcomes associated with two distinct potassium replacement protocols in critically ill patients.

Aims and Objectives

The primary aim of this prospective observational study was to compare clinical outcomes associated with aggressive versus conservative potassium replacement strategies in critically ill patients admitted to the ICU.

Specific objectives were:

1. To compare the incidence of potassium-related complications, including arrhythmias and cardiac events, between the two replacement strategies.
2. To evaluate and compare the effectiveness of each strategy in achieving normokalaemia and its impact on ICU length of stay.
3. To assess short-term outcomes, including 28-day mortality and any adverse effects attributable to the potassium replacement protocols.

Study Design and Setting

This prospective observational study was conducted at the intensive care unit (ICU) of Sukh Sagar Medical College and Hospital (SSMCH), Jabalpur, a tertiary care centre in Central India. The study period spanned from November 2024 to April 2025.

Study Population

A total of 125 critically ill patients admitted to the ICU during the study period were screened. Twelve patients were excluded due to death within 24 hours of ICU admission, resulting in 113 patients being included in the final analysis. Inclusion criteria were adult patients (aged ≥18 years) with documented hypokalaemia (serum potassium <3.5 mmol/L) requiring potassium replacement. Patients with end-stage renal disease on dialysis or those receiving palliative care were excluded.

Intervention Strategy

Patients were managed according to one of two potassium replacement protocols in use at the institution:

• Aggressive Replacement Group: Patients received intravenous potassium supplementation at a higher rate (typically >20 mEq/hour) under continuous cardiac monitoring.
• Conservative Replacement Group: Patients were administered potassium at a slower rate (<10 mEq/hour) with intermittent monitoring.

Treatment allocation was based on attending physician preference and existing ICU protocols; no randomization was performed, maintaining observational integrity.

Data Collection

Baseline demographics, clinical diagnosis, comorbidities, serum potassium levels, replacement details (dose, rate, route), and ECG findings were recorded. Clinical outcomes included time to achieve normokalaemia, occurrence of arrhythmias, ICU length of stay, and 28-day mortality. Monitoring was conducted for 72 hours post-initiation of potassium replacement, with follow-up data extracted from patient records.

Ethical Considerations

The study was approved by the Institutional Ethics Committee of SSMCH, Jabalpur. Informed consent was obtained from the patient or next of kin prior to enrollment. As the study involved standard-of-care treatment pathways, no experimental interventions were applied.

Statistical Analysis

Data were analyzed using standard statistical software. Descriptive statistics were used to summarize baseline demographic and clinical characteristics. Continuous variables were expressed as mean ± standard deviation (SD) and compared between groups using independent samples t-tests after verifying normality assumptions. Categorical variables were summarized as frequencies and percentages and analyzed using Chi-square tests or Fisher’s exact tests, depending on expected cell counts.

The primary outcomes analyzed included time to achieve normokalaemia, incidence of arrhythmia, cardiac arrest, and 28-day mortality. Secondary outcomes included ICU length of stay and the incidence of hyperkalaemia following potassium replacement. A two-tailed p-value of <0.05 was considered statistically significant. No adjustments were made for multiple comparisons, given the exploratory nature of the study.

The analysis aimed to identify clinically meaningful differences between aggressive and conservative potassium replacement strategies rather than establish causality. All analyses were performed on the final cohort of 113 patients who met inclusion criteria.

1. Baseline Characteristics

A total of 113 patients were included in the study, with 57 in the Aggressive group and 56 in the Conservative group. The mean age of patients in the Aggressive group was 57.6 ± 9.2 years, while that in the Conservative group was 60.3 ± 10.5 years. Males were predominant in both groups. The Aggressive group included 36 males (63.2%) and 21 females (36.8%), whereas the Conservative group included 31 males (55.4%) and 25 females (44.6%). The initial serum potassium level was slightly higher in the Aggressive group (3.10 ± 0.19 mmol/L) than in the Conservative group (3.04 ± 0.20 mmol/L). Table 1 summarizes the baseline demographic and biochemical characteristics of the two study groups.

Table 1. Baseline Demographic and Biochemical Characteristics of Aggressive and Conservative Potassium Replacement Groups (n = 113)

2. Primary Clinical Outcomes

The primary clinical outcomes demonstrated marked differences between the two potassium replacement strategies. Time to achieve normokalaemia was significantly shorter in the Aggressive group (mean 8.0 ± 3.0 hours) compared to the Conservative group (16.2 ± 3.3 hours). Arrhythmias were observed in 11 patients (19.3%) in the Aggressive group and 17 patients (30.4%) in the Conservative group. Cardiac arrest occurred in 5 patients (8.8%) in the Aggressive group and in 3 patients (5.4%) in the Conservative group. The 28-day mortality was lower in the Aggressive group at 5 patients (8.8%) compared to 12 patients (21.4%) in the Conservative group.Table 2 provides a detailed comparison of these outcomes, including the proportion of patients who did not experience the respective events.

Table 2. Detailed Comparison of Primary Clinical Outcomes Including Arrhythmia, Cardiac Arrest, and 28-Day Mortality across Study Groups

3. Secondary Outcomes

Secondary clinical outcomes were also evaluated to assess broader clinical implications of potassium replacement strategies. The mean ICU stay was notably shorter in the Aggressive group, averaging 5.1 ± 1.7 days, compared to 6.8 ± 1.6 days in the Conservative group. Hyperkalaemia, defined as serum potassium >5.5 mmol/L post-replacement, occurred more frequently in the Aggressive group, affecting 10 patients (17.5%) versus 6 patients (10.7%) in the Conservative group. Most patients in both groups did not experience hyperkalaemia, with rates of 82.5% and 89.3%, respectively. Table 3 summarizes these secondary outcomes across the study arms.

Table3: Comparison of ICU Stay Duration and Incidence of Hyperkalaemia between Aggressive and Conservative Potassium Replacement Groups

Statistical Comparison of Outcomes

Group-wise statistical comparisons were performed to evaluate the significance of observed differences in primary and secondary outcomes. Continuous variables were assessed using independent samples t-tests. Categorical variables were analyzed using Chi-square tests or Fisher’s exact test as appropriate based on cell counts.

Table4: Statistical Comparison of Primary and Secondary Clinical Outcomes Between Aggressive and Conservative Potassium Replacement Strategies

Interpretation of Results

- A statistically significant difference was observed in the time to achieve normokalaemia (p < 0.0001) and ICU stay duration (p < 0.0001), favoring the Aggressive replacement strategy.

- No statistically significant difference was detected between groups in arrhythmia (p = 0.253), cardiac arrest (p = 0.717), 28-day mortality (p = 0.106), or incidence of hyperkalemia (p = 0.441). These results suggest that while aggressive potassium correction was more efficient, it did not increase the rate of complications.

This prospective observational study explored the comparative outcomes of aggressive versus conservative potassium replacement strategies in a cohort of critically ill patients admitted to the ICU. Our findings revealed a significant reduction in time to achieve normokalaemia and ICU length of stay with aggressive replacement, without a corresponding increase in major complications or 28-day mortality.

Aggressive replacement led to a faster correction of serum potassium levels (8.0 ± 3.0 hours) compared to the conservative strategy (16.2 ± 3.3 hours), with a statistically significant difference (p < 0.0001). This reinforces the therapeutic efficiency of higher replacement rates, as also noted by Yousuf et al. [8], who demonstrated clinical benefits of timely potassium repletion in surgical and critical care contexts. Accelerated correction can help prevent complications like ventricular arrhythmias, especially in patients with underlying cardiac instability.

ICU stay was significantly shorter in the aggressive group (5.1 ± 1.7 days vs. 6.8 ± 1.6 days; p < 0.0001). Efficient electrolyte correction likely contributed to improved hemodynamic stability and reduced need for prolonged monitoring or escalation of care. These findings are consistent with Barlow et al. [9], who highlighted that fluid-electrolyte homeostasis is central to optimizing ICU throughput, and Bellomo et al. [10], who emphasized metabolic balance in renal support strategies.

Importantly, no statistically significant differences were observed in adverse outcomes such as arrhythmia (p = 0.253), cardiac arrest (p = 0.717), hyperkalemia (p = 0.441), or 28-day mortality (p = 0.106). This suggests that aggressive replacement, when appropriately monitored, does not increase the risk of iatrogenic complications. Hammond et al. [11] reported similar safety profiles in their retrospective ICU analysis. These findings also counter long-standing concerns from conservative fluid/electrolyte approaches [12,14] which argue for gradual correction to avoid sudden shifts in plasma osmolality or myocardial excitability.

From a systems perspective, reducing ICU stay by nearly 1.7 days per patient can translate to significant resource savings, particularly in high-volume or resource-limited settings. The adoption of an aggressive potassium replacement protocol may offer both clinical and logistical advantages when implemented under structured monitoring and dosing thresholds. While past trials such as the TIMI study [13] endorsed conservative repletion in cardiometabolic syndromes, more recent ICU-based research suggests that individualized replacement strategies—balancing efficacy and safety—are warranted.

This study has several limitations. The non-randomized design introduces potential selection bias, and being single-centered, the findings may not be generalizable across diverse ICU populations. The sample size, while adequate for primary outcomes, may lack power to detect differences in rarer complications. Additionally, the protocol-based allocation by attending physicians could introduce treatment bias.

In summary, our findings support the clinical utility of aggressive potassium replacement in ICU settings, offering faster correction and shorter ICU stay without increasing adverse event rates. These outcomes advocate for prospective, multi-center trials to validate the safety and effectiveness of such protocols across varied patient populations.

In this prospective study evaluating critically ill patients, aggressive potassium replacement demonstrated a clinically and statistically significant reduction in time to normokalaemia and ICU length of stay when compared with conservative strategies. Despite concerns about the potential for iatrogenic complications, the incidence of arrhythmia, cardiac arrest, hyperkalemia, and 28-day mortality did not differ significantly between the two approaches. These findings suggest that, when administered under structured protocols and appropriate monitoring, aggressive potassium repletion can enhance clinical efficiency without compromising patient safety.

Given the increasing burden on ICU resources and the imperative for effective, safe interventions, our study supports the incorporation of aggressive potassium replacement strategies into critical care protocols. Further multi-center randomized trials are warranted to validate these results and explore long-term outcomes, especially in heterogeneous ICU populations.

1. Bellomo, R., Baldwin, I., Ronco, C., & Kellum, J. A. (2021). ICU-based renal replacement therapy. Critical Care Medicine, 49(3), 406–418.
2. Cotton, B. A., Guy, J. S., Morris Jr, J. A., & Abumrad, N. N. (2006). The cellular, metabolic, and systemic consequences of aggressive fluid resuscitation strategies. Shock, 26(2), 115–121.
3. Claure-Del Granado, R., & Mehta, R. L. (2016). Fluid overload in the ICU: evaluation and management. BMC Nephrology, 17, 1–9.
4. Singh, B., Chlebek, S., & Krikorian, A. (2024). Diabetes in the critically ill patient: DKA, HHS, and beyond. In Diabetes Management in Hospitalized Patients: A Comprehensive Clinical Guide (pp. 65–76). Cham: Springer International Publishing.
5. Finney, S. J., Zekveld, C., Elia, A., & Evans, T. W. (2003). Glucose control and mortality in critically ill patients. JAMA, 290(15), 2041–2047.
6. Singh, B., Chlebek, S., & Krikorian, A. (2024). Diabetes in the critically ill patient: DKA, HHS, and Beyond. In Diabetes Management in Hospitalized Patients: A Comprehensive Clinical Guide (pp. 65-76). Cham: Springer International Publishing.
7. Malbrain, M. L., Van Regenmortel, N., Saugel, B., De Tavernier, B., Van Gaal, P. J., Joannes-Boyau, O., ... & Monnet, X. (2018). Principles of fluid management and stewardship in septic shock: it is time to consider the four D’s and the four phases of fluid therapy. Annals of Intensive Care, 8, 1–16.
8. Yousuf, M., et al. (2025). Potassium Replacement Practices and Their Association With Blood Transfusion Outcomes in Surgical and Critical Care Patients: A Systematic Review. Cureus, 17(5).
9. Barlow, A., et al. (2020). Intravenous fluid management in critically ill adults: a review. Critical Care Nurse, 40(6), e17–e27.
10. Bellomo, R., et al. (2021). ICU-based renal replacement therapy. Critical Care Medicine, 49(3), 406–418.
11. Hammond, D. A., et al. (2019). Effectiveness and safety of potassium replacement in critically ill patients: a retrospective cohort study. Critical Care Nurse, 39(1), e13–e18.
12. De Rosa, S., et al. (2017). Management of chronic kidney disease patients in the intensive care unit: mixing acute and chronic illness. Blood Purification, 43(1–3), 151–162.
13. TIMI Study Group. (1989). Comparison of invasive and conservative strategies after treatment with intravenous tissue plasminogen activator in acute myocardial infarction. NEJM, 320(10), 618–627.
14. Besen, B. A. M. P., et al. (2015). Fluid and electrolyte overload in critically ill patients: an overview. World Journal of Critical Care Medicine, 4(2), 116–129.