Journal of Emergencies, Trauma, and Shock
Home About us Editors Ahead of Print Current Issue Archives Search Instructions Subscribe Advertise Login 
Users online:333   Print this pageEmail this pageSmall font sizeDefault font sizeIncrease font size   


 
 Table of Contents    
ORIGINAL ARTICLE  
Year : 2015  |  Volume : 8  |  Issue : 1  |  Page : 34-38
Goal-directed diuresis: A case - control study of continuous furosemide infusion in critically ill trauma patients


Department of Surgery, Division of Trauma, Emergency Surgery and Surgical Critical Care, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA

Click here for correspondence address and email

Date of Submission21-Apr-2014
Date of Acceptance18-Aug-2014
Date of Web Publication30-Jan-2015
 

   Abstract 

Background: Excessive crystalloid administration is common and associated with negative outcomes in critically ill trauma patients. Continuous furosemide infusion (CFI) to remove excessive fluid has not been previously described in this population. We hypothesized that a goal-directed CFI is more effective for fluid removal than intermittent bolus injection (IBI) diuresis without excess incidence of hypokalemia or renal failure. Materials and Methods: CFI cases were prospectively enrolled between November 2011 and August 2012, and matched to historic IBI controls by age, gender, Injury Severity Score (ISS), and net fluid balance (NFB) at diuresis initiation. Paired and unpaired analyses were performed to compare groups. The primary endpoints were net fluid balance, potassium and creatinine levels. Secondary endpoints included intensive care unit (ICU) and hospital length of stay (LOS), ventilator-free days (VFD), and mortality. Results: 55 patients were included, with 19 cases and 36 matched controls. Mean age was 54 years, mean ISS was 32.7, and mean initial NFB was +7.7 L. After one day of diuresis with CFI vs. IBI, net 24 h fluid balance was negative (−0.55 L vs. +0.43 L, P = 0.026) only for the CFI group, and there was no difference in potassium and creatinine levels. Cumulative furosemide dose (59.4mg vs. 25.4mg, P < 0.001) and urine output (4.2 L vs. 2.8 L, P < 0.001) were also significantly increased with CFI vs. IBI. There were no statistically significant differences in ICU LOS, hospital LOS, VFD, or mortality. Conclusions: Compared to IBI, goal-directed diuresis by CFI is more successful in achieving net negative fluid balance in patients with fluid overload with no detrimental side effects on renal function or patient outcome.

Keywords: Crystalloids, diuresis, furosemide, trauma

How to cite this article:
Yeh DD, Van Der Wilden GM, Cropano C, Chang Y, King DR, De Moya M, Fagenholz P, Kaafarani H, Lee J, Velmahos G. Goal-directed diuresis: A case - control study of continuous furosemide infusion in critically ill trauma patients. J Emerg Trauma Shock 2015;8:34-8

How to cite this URL:
Yeh DD, Van Der Wilden GM, Cropano C, Chang Y, King DR, De Moya M, Fagenholz P, Kaafarani H, Lee J, Velmahos G. Goal-directed diuresis: A case - control study of continuous furosemide infusion in critically ill trauma patients. J Emerg Trauma Shock [serial online] 2015 [cited 2020 Jul 4];8:34-8. Available from: http://www.onlinejets.org/text.asp?2015/8/1/34/150395



   Introduction Top


Volume repletion in the acutely hypovolemic injured patient is essential for maintaining perfusion to critical organs. Traditionally, this has been achieved through the infusion of isotonic crystalloids, sometimes in massive quantities. [1] However, it is increasingly recognized that overzealous crystalloid administration in critically ill-patients is detrimental to the outcome. For example, excessive fluid gain has been associated with increased risk of anastomotic dehiscence, abdominal compartment syndrome, risk of multiple-organ dysfunction, prolonged mechanical ventilation, delayed return of gastrointestinal function, and excess mortality. [2],[3],[4],[5],[6]

After resuscitation is complete, it is suggested that diuresis to rapidly remove excess fluid gained could be beneficial. Just as controlled resuscitation with prespecified endpoints (i.e., goal-directed resuscitation) has been demonstrated to be superior to an unstructured approach, [7] the converse (i.e., fluid removal) might similarly benefit from a planned approach.

Loop diuretics are the most commonly prescribed diuretics in the Intensive Care Unit (ICU) setting, and they work by blocking chloride reabsorption in the ascending loop of Henle. The subsequent reabsorption of sodium and water passively follow the chloride ion. Importantly, all diuretics (except spironolactone) must reach the luminal side of the nephron in order to exert their action. [8] In addition, the drug concentration must exceed a minimum threshold concentration at that site of action to evoke a response. Above this threshold, the diuretic response increases with increasing dose up to a maximum response, at which point escalating drug doses only serve to increase toxicity without diuretic benefit. [9] The goal of diuretic therapy, then, should be to maintain luminal drug concentrations somewhere between the minimum threshold and the maximum response for as long as possible. The extent of diuretic response is also dependent upon the time course of drug delivery to the active site. [10] Intermittent bolus dosing is associated with peaks and troughs and variability of luminal drug concentration, resulting in substantial time spent below the minimum threshold of efficacy. Theoretically, continuous infusion dosing results in a lower peak serum concentration, with more consistent drug delivery and urine output. This may translate into reduced risk of renal failure, ototoxicity, or electrolyte derangements. [11] Studies in healthy volunteers have concluded that an intravenous (IV) bolus is the least efficient mode of administration and that controlled infusion at maximum efficiency could increase diuretic response up to 2.3 times higher. [12]

It has previously been reported that the use of furosemide in critically ill, fully resuscitated trauma patients is safe and effective in promoting diuresis. [13] However, the optimal mode of delivery has not been adequately investigated. In clinical practice, intermittent bolus dosing results in brisk, immediate diuresis, but this effect soon wears off, and the degree of fluid removal is often sub-optimal, especially when repeat dosing is reliant upon physician discretion. A nurse-driven continuous infusion protocol, on the other hand, may enhance overall diuretic use when explicit diuresis goals are stated at the outset and strict parameters guide subsequent dose adjustments. Similar nurse-driven protocols for heparin and insulin infusion have been in long-standing use and are widely accepted as superior to dosing based on individual physician discretion.

In 2011, we developed a sliding scale continuous furosemide infusion (CFI) protocol that stated a daily net negative fluid balance goal (−600 to −2000 mL) at the outset. With the end point set in advance, we were thus able to calculate the necessary hourly net negative fluid balance required to achieve that goal and adjust the CFI accordingly. The aim was to achieve more reliable and consistent diuresis with less variability in urine output and potentially less hemodynamic swings. We hypothesized that the use of a protocolized CFI is safe and more effective in fluid removal than intermittent bolus injection by physician discretion in diuretic-naïve, fully resuscitated, fluid overloaded critically ill trauma patients.


   Materials and methods Top


Design

This is a prospective case-control study in which we compared patients that were treated following the new CFI protocol (CASES - CFI) with contemporaneous patients who received intermitted bolus injection of furosemide guided by physician discretion (CONTROLS - IBI). The cases were prospectively enrolled from November 2011 to August 2012. These patients were matched to controls at a 1:2 ratio. Matching criteria were age (±10 years), gender, Injury Severity Score (ISS) (±10), APACHE 2 score (±3), and net fluid balance at the initiation of diuresis (±2.5 L).

Protocol development

Based on our review of the literature as well as our hospital data, we developed the CFI protocol. Within our division, we reached consensus on the addition of this protocol to daily practice in which diuresis based on physician discretion had been the standard of care. The inclusion criteria for patients to enter the CFI study group were: Admission to the surgical ICU, an attending physician judgment that the patient needed diuresis, age >18 years, >5.0 L net fluid positive since ICU admission, anticipated ICU length of study >24 h after initiation of diuresis, and a hemodynamically stable status (defined as mean arterial pressure >60 without vasopressor requirement for >12 h, heart rate (HR) <120, and base deficit > −3).

The CFI protocol began with a 10 mg IV furosemide loading dose, followed by an initial infusion rate of 2 mg/h. After 4 h (and every 4 h thereafter), the net fluid balance was assessed for underachievement, overachievement, or target diuresis. If the net negative fluid balance was under the stated goal, an additional 10 mg IV loading dose was given, and the infusion rate was increased by 1 mg/h. If the net negative fluid balance was over the stated goal, the infusion was temporarily discontinued for 1 h and resumed at a rate 1 mg/h less than the previous rate. No changes were made if the target diuresis was achieved [Figure 1]. In the IBI group, furosemide was prescribed as per usual clinical practice in diuretic-naive patients; initial doses were usually 10 mg or 20 mg IV, and subsequent doses were given at the clinician's discretion.
Figure 1: Continuous furosemide infusion protocol

Click here to view


Safety parameters for discontinuation of the GDD protocol are stated in [Figure 2]. Serum potassium levels were monitored twice a day and aggressively replaced as per standard of care.
Figure 2: Safety limits to discontinue GDD protocol

Click here to view


Data collection

Data collection included baseline demographics (age, gender, race), mechanism of injury, surgical diagnosis, comorbid medical conditions, physiologic parameters (such as systolic blood pressure, mean arterial blood pressure, HR, urine output, and net fluid balance), laboratory data (creatinine, potassium, blood gas), and clinical outcomes. The primary outcomes of interest were the total milligrams of furosemide and total urine output for the 1 st day of diuresis. Secondary outcomes included net 24 h fluid balance, hospital and ICU length of stay (LOS), ventilator-free days (VFD), and mortality.

Statistical analysis

We compared the CFI (cases) and IBI (controls) groups to identify differences in patient characteristics and outcomes. Continuous variables were summarized using mean ± standard deviation and compared by Student's t-tests, or summarized using median with interquartile and compared by Wilcoxon rank sum tests, whichever appropriate. Categorical variables were compared by Fisher's exact test. Statistical significance was considered as a two-sided P < 0.05. All statistical analyses were performed using SAS version 9.3 (The SAS Institute, Cary, NC, USA). This study was approved by our Institutional Review Board (no. 2011P002771) and complies with the ethical standards laid down in the 1964 declaration of Helsinki and its later amendments.


   Results Top


Fifty-five patients were included, with 19 CFI cases, and 36 IBI controls matched 1:2 except for two patients for whom second IBI controls could not be found. For CFI cases, mean age was 54 years, mean ISS was 32.7, and mean initial TBB was +7.7 L. After 1-day of diuresis with CFI versus IBI, net 24 h fluid balance was negative (−0.55 L vs. +0.43 L, P = 0.026) and potassium and creatinine values were not significant different. Cumulative furosemide dose (59.4 mg vs. 25.4 mg, P < 0.001) and urine output (4.2 L vs. 2.8 L, P < 0.001) were significantly increased in the CFI group, compared with the IBI group, and vital signs before and after initiating diuresis were not significantly different in both groups. There were no statistically significant differences in ICU or hospital LOS, VFD, PO 2 /FiO 2 (P/F) ratio or mortality [Table 1].
Table 1: Demographics and outcomes

Click here to view



   Discussion Top


In this case - control study, we report that the use of protocolized CFI, or goal-directed diuresis, resulted in significantly more furosemide administration with resultant more diuresis and net negative fluid balance when compared with diuresis directed by physician discretion and intermittent bolus injection. It is reassuring to note that in both groups, vital signs were not affected, and usual clinical parameters of acute kidney injury (blood urea nitrogen, creatinine) were likewise unchanged.

Although our study focused exclusively on critically ill injured patients, our results are consistent with those in other studied populations, mainly cardiac surgery and congestive heart failure patients. Two meta-analyses of randomized controlled trials in patients with acute decompensated heart failure have demonstrated superior weight loss with CFI compared to IBI without any significant differences in electrolyte imbalances or side effects. [14],[15] Trials in cardiac surgery have similarly reported improved diuretic efficiency with continuous infusion compared to bolus dosing: More negative fluid balance, decreased time to extubation, and significantly decreased oxygen requirements with fewer alterations in cardiac index and filling pressures. [11],[16],[17] In one report, cardiac index, central venous pressure, and diastolic pulmonary artery pressures remained unchanged and vasopressor support requirements decreased, despite an average of 5.7 L of urine output over a 24 h period. [17] CFI was also shown to be superior to bolus injection (at the same overall dose) in patients with chronic renal insufficiency, despite a six-fold lower peak plasma drug concentration. [18],[19] Drug-induced myalgias occurred exclusively during bolus injection dosing.

In a randomized trial of 22 MICU patients with pulmonary edema or fluid overload, Mojtahedzad reported that CFI, compared to bolus injection, was more effective in promoting diuresis and improved P/F ratio and had less dramatic changes in HR and potassium concentrations. [20] Salvador et al. reported in a systematic review of eight randomized trials (n = 254) that CFI dosing resulted in greater diuresis and a better safety profile (less tinnitus and hearing loss) when compared to bolus injection. [21]

However, not all studies have shown CFI superiority. [22],[23] A randomized study of protocolized continuous infusion versus protocolized bolus injection furosemide in mixed medical-surgical patients was terminated early for futility when interim analysis showed the equivalency of net diuresis. [24] The serum creatinine was significantly more increased in the bolus group though. The authors also compared enrolled protocolized patients (of either arm) with nonrandomized, nonprotocolized patients, and reported significant differences in net cumulative fluid balance (−4.5 L vs. −1.3 L), attributed to less cumulative furosemide dose (diuretic efficiency). For those patients who survived to discharge, protocolized diuresis significantly decreased ICU and hospital LOS. The act of protocolization, rather than a mode of delivery, appeared to drive the superior outcomes in this study.

It is important to note that if a CFI is to be employed, it should be accompanied by a loading dose to achieve drug levels quickly above minimum efficacious threshold. Without this loading dose, the onset of diuresis is delayed approximately 3 h. [11] A meta-analysis of continuous versus intermittent dosing of loop diuretics in hospitalized patients concluded that superior urine output and weight loss occurred only in trials where a loading dose preceded the continuous infusion. [25]

Our study has several limitations that must be acknowledged. First, this was not a randomized trial and therefore there may be unmeasured confounders, despite our best attempts to match the cases to controls. For example, the mere act of protocolization itself, rather than the continuous infusion, may have been the reason for the increased furosemide administration and diuresis. At the time of this study, we did not have a protocol for intermittent injections and hence we could not test this hypothesis. Regardless, we do not feel that this significantly detracts for the conclusion that protocolization resulted in significantly more diuresis than individual discretion. Secondly, the compliance with the protocol as written was not strictly enforced. Once the CFI protocol was initiated, clinicians were free to deviate. When this occurred, it was almost always early cessation of the infusion (in the absence of laboratory or clinical derangements). Stricter adherence to the protocol may have led to more dramatic differences between groups. Other protocol deviations, such as absent loading dose and inappropriate dose de-escalations, were common as well. However, in this early experience with CFI in this patient population, we felt it prudent to allow protocol deviations. Rather than quantify and catalog each deviation, we chose instead to analyze the patients on an intention-to-treat basis rather than per-protocol. As such, it is important to emphasize that our analysis and conclusions are on the strategy of goal-directed diuresis using CFI and not the flawless implementation of the protocol. This allowance reflects actual practice and increases external validity. Thirdly, we did not continue data collection beyond the first 24 h after initiating furosemide in either group. The reason for this is because we found that many patients had their infusion discontinued between the 2 nd and 4 th day of diuresis. We allowed the clinicians to discontinue the infusion once adequate diuresis (in their judgment) was complete. Fourthly, the sample size is admittedly small and therefore there is a risk of type 2 statistical error. Our study is underpowered to detect differences in clinically meaningful outcomes such as ventilator-free days, complications (pulmonary, gastrointestinal, cardiac, infectious, etc.), ICU or hospital LOS, and mortality. Our findings should be interpreted with caution and should be viewed as hypothesis-generating for future adequately powered studies. Nevertheless, this preliminary description of the use of protocolized furosemide infusion demonstrates proof of concept in this patient population and we have found our protocol to be generally well-tolerated and effective in attaining the goal of achieving negative fluid balance. At our own institution, we have become more comfortable with the protocol with increasing experience and continue to use it in appropriately selected patients.


   Conclusion Top


In significantly fluid overloaded, ICU trauma patients, goal-directed diuresis using a protocolized continuous furosemide infusion results in increased fluid removal without demonstrable morbidity.

 
   References Top

1.
Kutcher ME, Kornblith LZ, Narayan R, Curd V, Daley AT, Redick BJ, et al. A paradigm shift in trauma resuscitation: Evaluation of evolving massive transfusion practices. JAMA Surg 2013;148:834-40.  Back to cited text no. 1
    
2.
Schnüriger B, Inaba K, Wu T, Eberle BM, Belzberg H, Demetriades D. Crystalloids after primary colon resection and anastomosis at initial trauma laparotomy: Excessive volumes are associated with anastomotic leakage. J Trauma 2011;70:603-10.  Back to cited text no. 2
    
3.
Marjanovic G, Villain C, Juettner E, zur Hausen A, Hoeppner J, Hopt UT, et al. Impact of different crystalloid volume regimes on intestinal anastomotic stability. Ann Surg 2009;249:181-5.  Back to cited text no. 3
    
4.
Arlati S, Storti E, Pradella V, Bucci L, Vitolo A, Pulici M. Decreased fluid volume to reduce organ damage: A new approach to burn shock resuscitation? A preliminary study. Resuscitation 2007;72:371-8.  Back to cited text no. 4
    
5.
Cotton BA, Guy JS, Morris JA Jr, Abumrad NN. The cellular, metabolic, and systemic consequences of aggressive fluid resuscitation strategies. Shock 2006;26:115-21.  Back to cited text no. 5
    
6.
Upadya A, Tilluckdharry L, Muralidharan V, Amoateng-Adjepong Y, Manthous CA. Fluid balance and weaning outcomes. Intensive Care Med 2005;31:1643-7.  Back to cited text no. 6
    
7.
Rivers E, Nguyen B, Havstad S, Ressler J, Muzzin A, Knoblich B, et al. Early goal-directed therapy in the treatment of severe sepsis and septic shock. N Engl J Med 2001;345:1368-77.  Back to cited text no. 7
    
8.
Chennavasin P, Seiwell R, Brater DC, Liang WM. Pharmacodynamic analysis of the furosemide-probenecid interaction in man. Kidney Int 1979;16:187-95.  Back to cited text no. 8
[PUBMED]    
9.
Brater DC. Diuretic therapy. N Engl J Med 1998;339:387-95.  Back to cited text no. 9
    
10.
Kaojarern S, Day B, Brater DC. The time course of delivery of furosemide into urine: An independent determinant of overall response. Kidney Int 1982;22:69-74.  Back to cited text no. 10
[PUBMED]    
11.
Copeland JG, Campbell DW, Plachetka JR, Salomon NW, Larson DF. Diuresis with continuous infusion of furosemide after cardiac surgery. Am J Surg 1983;146:796-9.  Back to cited text no. 11
[PUBMED]    
12.
Alván G, Helleday L, Lindholm A, Sanz E, Villén T. Diuretic effect and diuretic efficiency after intravenous dosage of frusemide. Br J Clin Pharmacol 1990;29:215-9.  Back to cited text no. 12
    
13.
Yeh DD, Tang JF, Chang Y. The use of furosemide in critically ill trauma patients: A retrospective review. J Emerg Trauma Shock 2014;7:83-7.  Back to cited text no. 13
[PUBMED]  Medknow Journal  
14.
Wu MY, Chang NC, Su CL, Hsu YH, Chen TW, Lin YF, et al. Loop diuretic strategies in patients with acute decompensated heart failure: A meta-analysis of randomized controlled trials. J Crit Care 2014;29:2-9.  Back to cited text no. 14
    
15.
Amer M, Adomaityte J, Qayyum R. Continuous infusion versus intermittent bolus furosemide in ADHF: An updated meta-analysis of randomized control trials. J Hosp Med 2012;7:270-5.  Back to cited text no. 15
    
16.
Gulbis BE, Spencer AP. Efficacy and safety of a furosemide continuous infusion following cardiac surgery. Ann Pharmacother 2006;40:1797-803.  Back to cited text no. 16
    
17.
Magovern JA, Magovern GJ Jr. Diuresis in hemodynamically compromised patients: Continuous furosemide infusion. Ann Thorac Surg 1990;50:482-4.  Back to cited text no. 17
    
18.
Rudy DW, Voelker JR, Greene PK, Esparza FA, Brater DC. Loop diuretics for chronic renal insufficiency: A continuous infusion is more efficacious than bolus therapy. Ann Intern Med 1991;115:360-6.  Back to cited text no. 18
    
19.
Sanjay S, Annigeri RA, Seshadri R, Rao BS, Prakash KC, Mani MK. The comparison of the diuretic and natriuretic efficacy of continuous and bolus intravenous furosemide in patients with chronic kidney disease. Nephrology (Carlton) 2008;13:247-50.  Back to cited text no. 19
    
20.
Mojtahedzadeh M, Salehifar E, Vazin A, Mahidiani H, Najafi A, Tavakoli M, et al. Comparison of hemodynamic and biochemical effects of furosemide by continuous infusion and intermittent bolus in critically ill patients. J Infus Nurs 2004;27:255-61.  Back to cited text no. 20
    
21.
Salvador DR, Rey NR, Ramos GC, Punzalan FE. Continuous infusion versus bolus injection of loop diuretics in congestive heart failure. Cochrane Database Syst Rev 2005;CD003178.  Back to cited text no. 21
    
22.
Allen LA, Turer AT, Dewald T, Stough WG, Cotter G, O′Connor CM. Continuous versus bolus dosing of Furosemide for patients hospitalized for heart failure. Am J Cardiol 2010;105:1794-7.  Back to cited text no. 22
    
23.
Felker GM, O′Connor CM, Braunwald E, Heart Failure Clinical Research Network Investigators. Loop diuretics in acute decompensated heart failure: Necessary? Evil? A necessary evil? Circ Heart Fail 2009;2:56-62.  Back to cited text no. 23
    
24.
Schuller D, Lynch JP, Fine D. Protocol-guided diuretic management: Comparison of furosemide by continuous infusion and intermittent bolus. Crit Care Med 1997;25:1969-75.  Back to cited text no. 24
    
25.
Alqahtani F, Koulouridis I, Susantitaphong P, Dahal K, Jaber BL. A meta-analysis of continuous vs intermittent infusion of loop diuretics in hospitalized patients. J Crit Care 2014;29:10-7.  Back to cited text no. 25
    

Top
Correspondence Address:
Daniel Dante Yeh
Department of Surgery, Division of Trauma, Emergency Surgery and Surgical Critical Care, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114
USA
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0974-2700.150395

Rights and Permissions


    Figures

  [Figure 1], [Figure 2]
 
 
    Tables

  [Table 1]



 

Top
  
 
  Search
 
  
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Email Alert *
    Add to My List *
* Registration required (free)  


    Abstract
   Introduction
    Materials and me...
   Results
   Discussion
   Conclusion
    References
    Article Figures
    Article Tables

 Article Access Statistics
    Viewed3670    
    Printed98    
    Emailed1    
    PDF Downloaded13    
    Comments [Add]    

Recommend this journal