A multidisciplinary protocol improves electrolyte replacement and its effectiveness

An integrative review of potassium replacement protocol use in critical care: Development, use and critical care nurse autonomy

BACKGROUND

Potassium replacement protocols are used to standardise practice, reduce risk, and ensure timely potassium replacement, but there is considerable variability in their development and use, particularly as part of critical care nursing practice.

AIM

To synthesise the research evidence on how potassium replacement protocols are used in adult critical care; and how critical care nurses' role and practice is influenced by a potassium replacement protocol. The research question was 'How are protocols used by intensive care clinicians to guide potassium replacement in adult critical care?'

DESIGN

A structured integrative review was undertaken. A combination of keywords, synonyms, and Medical Subject Headings were used across the Ovid Medline and Embase databases. Records were independently assessed against inclusion and exclusion criteria. All papers were assessed for quality. A narrative synthesis was used to analyse and present the findings.

RESULTS

Ten studies were included in this review from 4076 records identified. Narrative synthesis revealed five categories: (i) protocol design demonstrating variation in protocol mechanisms, (ii) protocol rationale eliciting reasonings for protocol implementation, (iii) protocol use describing how protocols were nurse-driven enabling nursing autonomy (iv) protocol adherence highlighting variability in protocol compliance and (v) critical care nurse acceptability and feasibility coupling greater shared responsibility for patient care and improved clinician satisfaction.

CONCLUSION

Safe, high-quality care, supported by evidence continues to be a priority. Protocolised potassium replacement can improve patient outcomes and promote nurses' autonomy, efficiency, and job satisfaction.

IMPLICATIONS FOR CLINICAL PRACTICE

Recognising and promoting critical care nurses' expert assessment skills and clinical decision-making is essential for optimising efficient, safe, and high-quality patient care. Although protocol deviations are accommodated in protocol development, comprehensive documentation to justify protocol deviations is key to justifying practice. Understanding protocol deviations are crucial to inform future protocol development, improvements, and evaluation to further enhance critical care nursing practice.

Assessment of Electrolyte Replacement in Critically Ill Patients During a Drug Shortage

Purpose: The purpose of this study was to determine if national drug shortages of electrolyte replacement products negatively impact patient care. Methods: This study was a single-center, retrospective, observational cohort of adults admitted to the medical, surgical, or trauma intensive care unit (ICU) that were ordered or would have qualified for the general or continuous renal replacement therapy electrolyte replacement protocol (ERP) between April 2017 and August 2018. In October 2017, ERP use was suspended and enteral replacement was promoted due to inability to maintain consistent inventory of intravenous replacement products. The primary objective was to compare the percentage of patient days that at least 1 critically low value of potassium, magnesium, and/or phosphorus existed between protocolized and nonprotocolized electrolyte replacement. Secondary objectives included characterizing the ratio of enteral replacement to duration of critically low electrolyte values during protocolized and nonprotocolized electrolyte replacement. Results: A total of 288 patients were included. The mean percentage of ICU days with low electrolyte levels in the protocolized period was significantly higher than in the nonprotocolized period (21.4% vs 17.5%, P = .0238). There was a negative relationship between the total electrolyte replacement that was given enterally and the percentage of patient days with critically low values indicating that as enteral replacement increased, percentage of days with low values decreased. The association between percentage of enteral replacement and days with critically low electrolyte values was significantly lower in the protocolized period. Conclusion: Intravenous electrolyte replacement product shortages did not result in an increased incidence of critically low electrolyte values. Enteral replacement was associated with a decreased incidence of low electrolyte values.

Electrolyte Analysis and Replacement: Challenging a Paradigm in Surgical Patients

Postoperative patients are susceptible to alterations in electrolyte homeostasis. Although electrolytes are replaced in critically ill patients, stable asymptomatic non-intensive care unit (ICU) patients often receive treatment of abnormal electrolytes. We hypothesize there is no proven benefit in asymptomatic patients. In 2016, using the electronic medical records and pharmacy database at a university academic medical center, we conducted a retrospective cost analysis of the frequency and cost of electrolyte analysis (basic metabolic panel [BMP], ionized calcium [Ca], magnesium [Mg], and phosphorus [P]) and replacement (potassium chloride [KCl], Mg, oral/iv Ca, oral/iv P) in perioperative patients. Patients without an oral diet order, with creatinine more than 1.4, age less than 16 years, admitted to the ICU, or with length of stay of more than 1 week were excluded. Nursing costs were calculated as a fraction of hourly wages per laboratory order or electrolyte replacement. One hundred thirteen patients met our criteria over 11 months. Mean length of stay was 4 days; mean age was 54 years; and creatinine was 0.67 ± 0.3. Electrolyte analysis laboratory orders (n = 1,045) totaled $6,978, and BMP was most frequently ordered accounting for 36% of laboratory costs. In total, 683 doses of electrolytes cost the pharmacy $1,780. Magnesium was most frequently replaced, followed by KCl, P, and Ca. Nursing cost associated with electrolyte analysis/replacement was $7,782. There is little evidence to support electrolyte analysis and replacement in stable asymptomatic noncritically ill patients, but their prevalence and cost ($146/case) in this study were substantial. Basic metabolic panels, pharmacy charges for potassium, and nursing staff costs accounted for the most significant portion of the total cost. Considering these data, further research should determine whether these practices are warranted.

Safety of a Nurse-Driven Standardized Potassium Replacement Protocol in Critically Ill Patients With Renal Insufficiency

BACKGROUND

In critically ill patients, maintaining appropriate serum potassium concentrations requires careful supplementation to correct hypokalemia but avoid hyperkalemia. At the study institution, an institution-based, nurse-driven standardized electrolyte replacement protocol is used in critically ill patients with a serum creatinine concentration of 2 mg/dL or less. If the serum creatinine concentration is greater than 2 mg/dL, electrolyte replacement requires a physician order.

OBJECTIVE

To determine if standardized potassium supplementation is safe in critically ill patients with renal insufficiency not requiring renal replacement therapy.

METHODS

This study was an institutional review board-approved, single-center, retrospective evaluation of critically ill patients receiving intravenous potassium replacement per protocol. Patients were grouped according to serum creatinine concentration (≤ 2 mg/dL or > 2 mg/dL) at the time of replacement. The primary outcome was the incidence of hyperkalemia (potassium concentration ≥ 5 mEq/L) following potassium replacement. Secondary outcomes were the incidence of hyperkalemia, change in serum potassium concentration, and need for hyperkalemia treatment. Outcomes were analyzed using χ2 and t tests.

RESULTS

Of 814 patients screened, 145 were included (99 with serum creatinine ≤ 2 mg/dL and 46 with serum creatinine > 2 mg/dL). The incidence of hyperkalemia was not different between groups (P = .57). Five patients experienced hyperkalemia; none received hyperkalemia treatment. Change in serum potassium was similar for patients in the 2 groups (P = .33).

CONCLUSIONS

A standardized, nurse-driven electrolyte replacement protocol can be used safely in critically ill patients with renal insufficiency not requiring renal replacement therapy.

The Impact of IV Electrolyte Replacement on the Fluid Balance of Critically Ill Surgical Patients

Avoiding excess fluid administration is necessary when managing critically ill surgical patients. The aim of this study was to delineate the current practices of IVelectrolyte (IVE) replacement in a surgical ICU and quantify their contribution to the fluid balance (FB) status. Patients admitted to the surgical ICU over a six-month period were reviewed. Patients undergoing dialysis and those with ICU stay <72 hours were excluded. A total of 248 patients were included. The median age was 60 years, and 57 per cent were male. Overall, 1131 patient ICU days were analyzed. The median daily FB was 672 mL. IVEs were administered in 62 per cent of ICU days. In days that IVEs were used, negative FB was significantly less likely to be achieved (62% vs 69%, P = 0.02). The most commonly administered IVE was calcium (32% of ICU days); however, the largest volume of IVE was administered in the form of phosphorus (median 225 mL). Diuretics were administered in 17 per cent of ICU days. Patients who received diuretics were significantly more likely to receive IVE (70% vs 61%, P = 0.02). Administration of IVE may contribute to the daily positive FB of surgical ICU patients. Implementation of practices that can ameliorate this effect is encouraged.

Effectiveness and Safety of Potassium Replacement in Critically Ill Patients: A Retrospective Cohort Study

BACKGROUND

Rules of thumb for potassium replacement are used in intensive care units despite minimal empirical validation.

OBJECTIVE

To evaluate the effectiveness and safety of rule-of-thumb potassium replacement in critically ill patients with mild and moderate hypokalemia.

METHODS

A retrospective, observational study was done of patients with mild (potassium, 3-3.9 mEq/L) and moderate (potassium, 2-2.9 mEq/L) hypokalemia admitted to a medical intensive care unit who received potassium replacement. Expected and actual frequencies of replacement that achieved target potassium concentrations (≥ 4 mEq/L) were compared by using a χ² test. Logistic regression analysis was used to assess whether rule-of-thumb administration affected the probability of target attainment within 24 hours of replacement.

RESULTS

Serum potassium concentrations were checked within 24 hours after potassium replacement on 354 of 577 days (61.4%) when replacement was provided. Concentrations were within target range in 82 instances (23.2%). Of 62 episodes of replacement expected to achieve the target according to the rule-of-thumb estimation, 22 did (35%). Rule-of-thumb administration was associated with greater likelihood of target attainment (odds ratio, 2.12; 95% CI, 1.18-3.85; P = .01). This difference in likelihood remained significant after adjustment for covariates (odds ratio, 2.18; 95% CI, 1.04-4.56; P = .04).

CONCLUSION

In critically ill patients given potassium replacement without regard to a formal protocol, the target serum potassium concentration was achieved more often than expected according to the rule-of-thumb estimation but less than one-third of the time.

Safety, Efficacy, and Timeliness of Intravenous Potassium Chloride Replacement Protocols in a Pediatric Cardiothoracic Intensive Care Unit

OBJECTIVE

Hypokalemia in children following cardiac surgery occurs frequently, placing them at risk of life-threatening arrhythmias. However, renal insufficiency after cardiopulmonary bypass warrants careful administration of potassium (K⁺). Two different nurse-driven protocols (high dose and tiered dosing) were implemented to identify an optimal K⁺ replacement regimen, compared to an historical low-dose protocol. Our objective was to evaluate the safety, efficacy, and timeliness of these protocols.

DESIGN

A retrospective cohort review of pediatric patients placed on intravenous K⁺ replacement protocols over 1 year was used to determine efficacy and safety of the protocols. A prospective single-blinded review of K⁺ repletion was used to determine timeliness.

PATIENTS

Pediatric patients with congenital or acquired cardiac disease.

SETTING

Twenty-four-bed cardiothoracic intensive care unit in a tertiary children's hospital.

INTERVENTIONS

Efficacy was defined as fewer supplemental potassium chloride (KCl) doses, as well as a higher protocol to total doses ratio per patient. Safety was defined as a lower percentage of serum K⁺ levels ≥4.8 mEq/L after a dose of KCl. Between-group differences were assessed by nonparametric univariate analysis.

RESULTS

There were 138 patients with a median age of 3.0 (interquartile range: 0.23-10.0) months. The incidence of K⁺ levels ≥4.8 mEq/L after a protocol dose was higher in the high-dose protocol versus the tiered-dosing protocol but not different between the low-dose and tiered-dosing protocols (high dose = 2.2% vs tiered dosing = 0.5%, P = .05). The ratio of protocol doses to total doses per patient was lower in the low-dose protocol compared to the tiered-dosing protocol (P < .05). Protocol doses were administered 45 minutes faster (P < .001).

CONCLUSION

The tiered-dosed, nurse-driven K⁺ replacement protocol was associated with decreased supplemental K⁺ doses without increased risk of hyperkalemia, administering doses faster than individually ordered doses; the protocol was effective, safe, and timely in the treatment of hypokalemia in pediatric patients after cardiac surgery.

Effectiveness and Safety of Magnesium Replacement in Critically Ill Patients Admitted to the Medical Intensive Care Unit in an Academic Medical Center: A Retrospective, Cohort Study

Background:

“Rules of thumb” for the replacement of electrolytes, including magnesium, in critical care settings are used, despite minimal empirical validation of their ability to achieve a target serum concentration. This study’s purpose was to evaluate the effectiveness and safety surrounding magnesium replacement in medically, critically ill patients with mild-to-moderate hypomagnesemia.

Methods:

This was a single-center, retrospective, observational evaluation of episodes of intravenous magnesium replacement ordered for patients with mild-to-moderate hypomagnesemia (1.0-1.9 mEq/L) admitted to a medical intensive care unit from May 2014 to April 2016. The primary effectiveness outcome, achievement of target serum magnesium concentration (≥2 mEq/L) compared to expected achievement using a “rule of thumb” estimation that 1 g intravenous magnesium sulfate raises the magnesium concentration 0.15 mEq/L, was tested using 1-sample z test. Logistic regression analysis was conducted to assess the effect of infusion rate on target achievement.

Results:

Of 152 days on which magnesium replacements were provided for 72 patients, a follow-up serum magnesium concentration was checked within 24 hours in 89 (58.6%) episodes. Of these 89 episodes, serum magnesium concentration reached target in only 49 (59.8%) episodes compared to an expected 89 (100%; P < .0001). There was no significant association between infusion rate and achievement of the target serum magnesium concentration (odds ratio: 0.962, 95% confidence interval: 0.411-2.256).

Conclusions:

Medically, critically ill patients who received nonprotocolized magnesium replacement achieved the target serum magnesium concentration less frequently than the “rule of thumb” estimation predicted.

Perioperative Care of the Liver Transplant Patient

With the evolution of surgical and anesthetic techniques, liver transplantation has become "routine," allowing for modifications of practice to decrease perioperative complications and costs. There is debate over the necessity for intensive care unit admission for patients with satisfactory preoperative status and a smooth intraoperative course. Postoperative care is made easier when the liver graft performs optimally. Assessment of graft function, vigilance for complications after the major surgical insult, and optimization of multiple systems affected by liver disease are essential aspects of postoperative care. The intensivist plays a vital role in an integrated multidisciplinary transplant team.

Effects of Electrolyte Replacement Protocol Implementation in a Medical Intensive Care Unit

PURPOSE

To evaluate the effects of electrolyte replacement protocol (ERP) implementation in the medical intensive care unit (MICU) setting. We hypothesized that a protocol would reduce the time of replacement dose administration and increase provider satisfaction with the process of electrolyte replacement.

METHODS

This was a retrospective review of electronic medical record data before and after implementation of a standardized ERP in an 18-bed military tertiary care MICU.

RESULTS

Median time from abnormal laboratory result to time of documented dose administration for potassium decreased from 180 to 98 minutes ( P < .01), phosphorus decreased from 190 to 135 minutes ( P < .01), calcium decreased from 95 to 61 minutes ( P < .01), and magnesium decreased from 155 to 149 minutes ( P < .01). Overall, there was a significant reduction in time to electrolyte repletion from 146 to 98 minutes ( P < .01) for all electrolytes. Nursing satisfaction for autonomy, timeliness, effectiveness, and the need to seek orders was all improved ( P < .01), and physicians saved 4.4 minutes/patient/day ( P = .04).

CONCLUSIONS

Electrolyte replacement protocols can be safely implemented in the MICU and reduce the time from abnormal laboratory result to electrolyte replacement dose administration. They can improve provider satisfaction and reduce physician time with the process of electrolyte replacement.

Evaluation of an Intravenous Potassium Dosing Algorithm for Hypokalemic Critically Ill Patients

PURPOSE

The intent of this study was to evaluate the safety and efficacy of an intravenous (IV) potassium (K) dosing algorithm for hypokalemic critically ill trauma patients.

METHODS

Adult patients, admitted to the trauma intensive care unit from June 2010 to October 2012 and who received IV K therapy according to a standardized dosing algorithm, were retrospectively evaluated. Patients who received IV K during resuscitation or following initiation of nutrition therapy, IV fluids containing >20 mEq/L of potassium, or medications known to alter K homeostasis or those with an arterial pH change >0.1, diarrhea, hypomagnesemia, renal impairment, or morbid obesity were excluded.

RESULTS

In total, 715 patients were reviewed to obtain 100 evaluable patients. Serum K for patients with mild depletion (serum K, 3.5-3.9 mEq/L, n = 74) remained unchanged at 0.0 ± 0.3 mEq/L ( P = ns) following 46 ± 8 mEq. Serum K increased by 0.4 ± 0.3 mEq/L ( P = .001) following 78 ± 18 mEq during moderate depletion (serum K, 3-3.4 mEq/L). None of the patients experienced hyperkalemia (serum K, >5.2 mEq/L) postinfusion. The presence of traumatic brain injury (TBI) blunted the response to IV K for mild K depletion as only 26% had an increase in serum K compared with 55% of patients without TBI ( P = .025).

CONCLUSIONS

The Nutrition Support Service-guided IV K dosing algorithm was safe for patients with mild and moderate hypokalemia and efficacious for those with moderate hypokalemia. Further study in patients with severe hypokalemia (serum K, <3 mEq/L) is warranted.

Preventing hypokalemia in critically ill patients

BACKGROUND

Many therapies used in critical care cause potassium depletion. Current practice relies on potassium replacement protocols after a patient becomes hypokalemic. Potassium bolus therapy creates risk for patients, is costly, and increases nurses' workload.

OBJECTIVES

To determine if administering potassium preemptively in maintenance intravenous fluid would prevent episodes of hypokalemia and reduce the need for potassium boluses.

METHODS

Medical records of 267 patients with normal potassium and creatinine levels at admission who did not receive total parenteral nutrition were reviewed. The 156 patients who met the study criteria were categorized by group: those who received potassium via maintenance intravenous fluid (treatment; n = 76) and those who did not (control; n = 80). The treatment group had potassium chloride or acetate added to intravenous fluid delivered at 36 to 72 mmol/d.

RESULTS

The 2 groups did not differ significantly in age, race, sex, or admitting diagnosis. Type of diagnosis, length of stay, and potassium and creatinine levels at admission did not affect the number of potassium boluses for either group. The patients given maintenance potassium preemptively received significantly fewer (P < .001) potassium boluses (0.8) than did the control group (2.73), for a mean savings of $231 per patient for the treatment group.

CONCLUSIONS

Patients with normal potassium and creatinine levels at admission benefitted from a maintenance intravenous dose of potassium of 72 to 144 mmol/L per day. Compared with control patients, patients receiving this dose avoided detrimental hypokalemic events, had fewer invasive procedures and lower costs, and required less nursing care.

Evaluation of an electrolyte repletion protocol for cardiac surgery intensive care patients

BACKGROUND

Implementation of electrolyte repletion protocols to facilitate and ensure the safety of electrolyte control is common practice in intensive care units (ICUs). However, few protocols have been evaluated and validated.

OBJECTIVE

To evaluate the effectiveness and safety of an electrolyte repletion protocol in a large, homogeneous group of postoperative patients.

METHODS

A retrospective study of patients admitted to the surgical ICU following coronary artery bypass grafting or heart valve replacement was undertaken at the Centre hospitalier universitaire de Sherbrooke, a 682-bed tertiary care hospital in Sherbrooke, Quebec. The proportion of measured values for serum potassium concentration that were within the desired range was compared between patients treated according to the electrolyte repletion protocol and those treated with the traditional approach to electrolyte repletion. Management of magnesium, phosphorus, and ionized calcium balance was also compared. The incidence of cardiac arrhythmias was documented, and the safety of the electrolyte repletion protocol was evaluated by determining and comparing proportions of values for serum electrolyte concentration that were above the desired range.

RESULTS

In total, 627 patients were included in the study: 312 in the control group and 315 in the protocol group. The proportion of patients with 100% of morning values for serum potassium concentration within the normal range was significantly higher in the protocol group than in the control group (66.1% versus 56.8%; p = 0.018). In the protocol group, significantly more patients received one or more replacement doses of magnesium and phosphorus (p < 0.001). The proportions of serum electrolyte values above the normal range were similar between the 2 groups, and there was no difference in the incidence of cardiac arrhythmias.

CONCLUSIONS

The electrolyte repletion protocol was more efficacious than traditional electrolyte repletion in maintaining normal serum potassium concentration and was safe.

Safety and effectiveness of intensive insulin protocol use in post-operative liver transplant recipients

There is a paucity of data regarding the safety and utility of strict glycemic control in patients undergoing orthotopic liver transplantation (OLT). Although control of hyperglycemia may theoretically be beneficial, concerns exist regarding the effect of iatrogenic hypoglycemia on graft function. We performed a retrospective observational study evaluating the impact of the introduction of a nurse-initiated glycemic control protocol on OLT recipients cared for in a single intensive care unit (ICU). The medical records of 84 OLT recipients in 2003 (Preprotocol group) and 77 recipients in 2007 (Protocol group) were reviewed. Data regarding demographics, medical history, physiology, perioperative anesthesia and surgical events, ICU stay, graft function, and mortality were abstracted. Glucose values on admission to ICU, at 2, 6, 12, 18, and 24 hours after surgery, and at 4 am on the morning after OLT were recorded. Patients in the Protocol group achieved better and faster glycemic control. The odds ratio for severe hyperglycemia (glucose >250 mg/dL) in the Protocol group was 0.16 (95% confidence interval, 0.09-0.28). Hypoglycemia was not observed. The 1-year mortality was 5.3% in the Preprotocol and 6.0% in the Protocol group (P = .86). The rate of graft loss was low, and there was no difference in the incidence of graft failure between the Preprotocol and Protocol groups. We conclude that nurse-initiated and -directed glycemic control protocols can be safely and effectively used in the early period after OLT, though we did not identify a beneficial effect on graft function.