Preventing Intradialytic Hypotension

Copyright 2017 American Nephrology Nurses Association (ANNA) All rights reserved. No part of this document may be reproduced or transmitted in any form without the written permission of the American Nephrology Nurses Association.

Preventing Intradialytic Hypotension: Translating Evidence into Practice Wendi Bradshaw Paul N. Bennett Alison M. Hutchinson

ntradialytic hypotension (IDH) is a medical emergency consisting of a sudden, symptomatic drop in blood pressure (BP) during hemodialysis that will lead to death if not treated. IDH is the most frequent severe side effect of hemodialysis treatment, with a reported incidence from 25% to 50% (Flythe, Xue, Lynch, Curhan, & Brunelli, 2014). Added to the burden of symptomatic episodes of hypotension, contemporary research suggests that relative – or asymptomatic – hypotension, may contribute significantly to morbidity in patients undergoing hemodialysis through subtle effects of organ damage due to localized hypoperfusion (Dorairajan, Chockalingam, & Misra, 2010; McIntyre & Goldsmith, 2015; Meredith, Pugh, Sutherland, Tarassenko, & Birks, 2015). Many studies examining IDH adopt the international guideline definition: “A decrease in systolic blood pressure by greater than 20 mmHg or a decrease in mean arterial pressure (MAP) by greater than 10 mmHg with symptoms” (Kooman et al., 2007, p. ii23; National Kidney Foundation [NKF], 2005). However, as an all-encompassing definition, this fails to recognize individual BP variation; to take relative, asymptomatic hypotension into account; or to con-

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Wendi Bradshaw, MN, RN, is a Clinical Nurse Specialist, Dandenong Dialysis Unit, Monash Health, Clayton, Victoria; and an Associate Lecturer, Deakin University, Burwood, Victoria, Australia. Paul N. Bennett, PhD, BN, RN, DipNg, Renal Cert., GradCertSc(App Stats), MHSM, is an Honorary Professor, Deakin University, Burwood, Victoria, Australia; and Director of Medical Clinical Affairs, Satellite Healthcare, San Jose, CA. Cherene Ockerby, BA(Hons), is a Research Assistant, the Centre for Nursing Research, Deakin University, Burwood, Victoria; and Monash Health Partnership, Clayton, Victoria, Australia.

Nephrology Nursing Journal

Continuing Nursing Education

Cherene Ockerby Peter G. Kerr

Copyright 2017 American Nephrology Nurses Association. Bradshaw, W., Bennett, P.N., Hutchinson, A.M., Ockerby, C., & Kerr, P.G. (2017). Preventing intradialytic hypotension: Translating evidence into practice. Nephrology Nursing Journal, 44(2), 131-138, 151. Intradialytic hypotension (IDH) remains the most frequent severe side effect of hemodialysis. This prospective, exploratory study aimed to measure the compliance of an IDH prevention pathway and to identify the effects of pathway use on hypotension incidence. Additionally, the study explored barriers and facilitators to pathway implementation in five hemodialysis centers. Instituting an ultrafiltration pause decreased the odds of hypotensive episodes by 44% (OR = 0.56, 95% CI = 0.20 to 1.56, χ21 = 1.25, p = 0.26); however, audits indicated that mean compliance with the pathway (n = 2,711) was only 34%. Focus group interviews revealed nurse concern regarding lack of education prior to pathway implementation and patient apprehension at ultrafiltration pausing without symptoms. This highlights the importance of active translational strategies for clinicians to optimize clinical outcomes in reducing hypotension incidence. Key Words: Asymptomatic intradialytic hypotension, hemodialysis, hypoperfusion, mean arterial pressure, nursing.

sider the significance of the diastolic value during ultrafiltration (UF). These factors are important because the first physical response to UF in hemodialysis is a compensatory increase in stroke volume and heart rate (as cardiac output) and rise in peripheral resistance through vasoconstriction (Chou et al., 2006). During initial fluid removal, the diastolic BP value may rise correspondingly when the systolic BP value falls, meaning that a BP may appear lower according to its systolic value, when in

fact, the physiological compensation of rising vascular resistance (as reflected in the diastolic BP) in response to reduced cardiac output (the lower systolic value) works to adjust the MAP (Bradshaw & Bennett, 2015). This is a frequent pattern through stable treatment sessions (see Table 1). However, by the time symptoms occur with a low BP, it is too late; the patient may be critically unwell. There is increasing recognition that many episodes of IDH are preceded by gradually decreasing MAP

Alison M. Hutchinson, PhD, RN, BAppSc (Adv. Nsg), Cert of Midwifery, MBioeth, is a Professor of Nursing, Deakin University, School of Nursing and Midwifery, Burwood, Victoria; and the Chair of Nursing, the Centre for Quality and Patient Safety Research, Monash Health Partnership, Clayton, Victoria, Australia. Peter G. Kerr, PhD, MB, BS, FRACP, is Head of Nephrology, Department of Nephrology, and Professor of Medicine, Monash University, Clayton, Victoria, Australia. Acknowledgement: The study was supported by a Monash Health Emerging Research Fellowship Grant (WB). Statement of Disclosure: The authors reported no actual or potential conflict of interest in relation to this continuing nursing education activity. Note: The Learning Outcome, additional statements of disclosure, and instructions for CNE evaluation can be found on page 139.

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Preventing Intradialytic Hypotension: Translating Evidence into Practice

Table 1 Intradialytic Blood Pressure Measures

Methods

Blood Pressure – History

Time h:min

SYS mmHg

DIA mmHg

MAP mmHg

PULSE 1/min

9:23

120

69

95

61

7:04 8:23

10:30 10:40

11:07

155 130 104 109 106

55 65 43

102 89 64

55

77

56

78

99 65 67 82 80

Notes: SYS = systolic blood pressure value, DIA = diastolic blood pressure value, MAP = mean arterial pressure.

values, which may not be obvious in the BP metric alone (Bradshaw & Bennett, 2015). This position was supported by research indicating that pausing UF on recognition of MAP decrement substantially reduced the frequency of symptomatic hypotensive episodes (Bradshaw, Ockerby, & Bennett, 2011). This led to the development of an asymptomatic hypotension pathway algorithm that recommended pausing UF before a patient became symptomatic at the point of a decreased MAP to allow vascular refill and MAP recovery, after which time, safe fluid removal could be resumed (Bradshaw & Bennett, 2015). Utilization of the algorithm allows vascular refill by pausing UF for 10 minutes, after which UF is resumed. The need to recognize relative low BP differentially from symptomatic hypotensive episodes formalized working definitions of hypotension within the algorithm. Therefore, we defined IDH as a sudden, unexpected, and symptomatic drop in BP requiring intervention, irrespective of metric value. Correspondingly, asymptomatic intradialytic hypotension (A-IDH) was defined as a reduction in the MAP by more than 30 mmHg as compared to pre-dialysis BP, and/or a drop in the MAP to less than 70 mmHg, without symptoms – unless this is usual for the patient. Table 1 illustrates BP measures in a patient who exhibited an asymp-

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tomatic low MAP and BP (MAP decrease of 38 mmHg to a value less than 70 mmHg) at 10.30 a.m. with a subsequent 10-minute UF pause. The MAP had increased when rechecked at 10.40 a.m., allowing resumption of UF without incident. In 2014, the Intradialytic Hypotension Prevention Pathway algorithm was formally registered with the organization’s Centre for Clinical Effectiveness and introduced into the network’s five dialysis centers. Introduction of the algorithm was accompanied by limited facilitation consisting of an education session at each center. Comprehensive facilitation to support the translation of new evidence into practice (Harvey & Kitson, 2015) was not performed. In the absence of a facilitation strategy to support implementation and with limited evidence about the extent of adherence to the algorithm in practice, attention was drawn to the need to formally investigate its uptake within satellite dialysis centers.

Aims The aims of this mixed methods study were to 1) determine the extent of algorithm compliance across the five satellite dialysis centers, 2) identify the effect of the algorithm use on hypotension incidence, and 3) explore perceived barriers to algorithm use in clinical practice.

Design Audit and focus groups were used to generate data to address the study aims. Patient charts were audited retrospectively to determine compliance with the algorithm. Focus groups were conducted to elicit nurse perceptions regarding barriers to and facilitators of adherence to the algorithm.

Setting and Participants The study was conducted in five dialysis centers located in five hospitals within one large healthcare service in Melbourne, Australia. Four centers operated as satellite sites, and one center was an acute inpatient facility. Hemodialysis machines used were Fresenius 4008S and 4008B; the dialysate temperature was 35.5˚ Celsius for all patients, and dialysate had a potassium content of 2 mmol/L (2 mEq/L) and a calcium content 1.3 mmoL (2.6 mEq/L). At the time of the study, the five centers ranged in size from nine to 18 hemodialysis chairs or beds, offering either two or three hemodialysis sessions per day, six days per week. Patient demographic data were collected, including age and comorbidities of diabetes or hypertension. The number of patients recruited from each center ranged from 22 in the acute inpatient center to 68 in one satellite center. Data for a four-week timeframe were collected, aiming for data from 12 dialysis sessions per patient. All patients in each center on the first two days of data collection (i.e., to capture data for patients attending each three-day per week treatment cycle) were recruited into the study. Medical record numbers were reviewed to identify patients treated across multiple centers and ensure they were only counted once. As per usual practice, sphygmomanometers were either manual or automatic, and BP measures were performed by registered nurses (RNs) who, in line with their registration, were deemed proficient in this skill.


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Total Treatments

2711 Was MAP documented? Yes 1,872 No 839

Was A-IDH Present?

Figure 1 Treatment Outcomes (n = 2,711)

UF Paused, at Least Once per Pathway?

Yes 87

Yes 108

Yes 335

Did MAP Recover? Was There Progression to Symptomatic IDH?

No 21

Yes 125

No 227

No 102

No 2376

Yes No Yes No

Yes No Yes No

Yes No

1 86

4

17 0

125 18 84

4

2372

2,711

Notes: Bold, italicized values in red represent symptomatic hypotensive episodes. MAP = mean arterial pressure, A-IDH = asymptomatic intradialytic hypotension, IDH = intradialytic hypotension.

Automatic sphygmomanometers generally record a MAP value; however, where a manual device was used, MAP was calculated according to the formula MAP = (SBP x 0.33) + (DBP x 0.66) (McDermott & Melloh, 2008). BPs were performed pre-dialysis, hourly, and post-dialysis. It is important to note that there is often a discrepancy between automatic sphygmomanometer readings when the MAP value is calculated manually because automatic machines equate their final MAP value by calculating arterial pulse wave velocity in accordance with heart rate. Automatic sphygmomanometers were not always available within all centers. Nurses within the participating centers were invited to take part in focus group interviews. In these centers, a typical ratio is three patients per nurse. Most satellite dialysis clinicians are bachelor level RNs, with diploma level enrolled nurses employed at some sites.

Ethical Considerations The study was approved as a lowrisk project by the Human Research


Ethics Committee of the healthcare service. De-identified data were collected from daily hemodialysis treatment worksheets at each center. Because no identifying data were collected through the audit, the ethics committee provided a waiver of consent. Nurses provided written informed consent to participate in focus groups and had the opportunity to withdraw on the day. Anonymity and confidentiality of data were assured, and participants were informed beforehand that sessions would be audio-recorded. Participants were also informed that following the project, data would be removed from the password-protected computer and disposed of through confidential document services after seven years of storage.

Audit of IDH Clinical Pathway Compliance Hemodialysis treatment worksheets at each dialysis center were audited to collect data covering a period of four weeks for every patient at that center. A coding tool was developed for the audit and was pre-tested on 12 randomly selected and de-iden-

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tified worksheets, which resulted in minor modifications to the tool. The tool contained five dichotomous (i.e., yes or no) items and was used progressively through each treatment – documentation of MAP, presence of A-IDH according to the study definition, consequent implementation of a 10-minute UF pause, recovery of the MAP, and occurrence of IDH. If the MAP was not documented on a worksheet, it was calculated from the recorded BP to assess for evidence of A-IDH. In this manner, the coding tool showed each treatment progressing to one of 20 possible outcomes (from 1 to 20), allowing a final summary of the 2,711 treatments according to the outcome categories. However, for clarity in the final compilation, the initial variable – MAP documentation – was removed, combining that category with the remaining four variables, resulting in reduction to 10 final outcomes. Figure 1 shows the coding tool with final outcomes to one of 10 possibilities for all treatments, with MAP documentation values noted.

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Table 2 A-IDH Episodes per Center

Treatments Where MAP Patients per Center Documented at (Total Treatments Least Once (%) Center on Worksheet Performed) Number 1

40 (480)

85.6%

4

68 (810)

31.7%

2 3 5

49 (588) 57 (680) 21 (153)

93.2%

UF Pause as Percentage of Treatments A-IDH Present (i.e., Resulting in Percentage of A-IDH Present Pathway Compliance) IDH Despite (Treatments) UF Pause (Treatments)

86.0% 78.6%

11.6% (56)

58.9% (33)

2

8.4% (68)

25% (17)

2

11.4% (67)

16.9% (115) 15.6% (24)

29% (19)

1

25.2% (29) 33%

0

(8)

0

Total IDH Progressed from Treatments Not Paused 0

10

6 1 5

Notes: MAP = mean arterial pressure, A-IDH = asymptomatic intradialytic hypotension, IDH = intradialytic hypotension.

Focus Group Interviews and Participant Recruitment Focus group interviews were conducted to address the third aim of the study to explore perceived barriers to algorithm use in clinical practice. Four weeks in advance of the intended sessions, invitations to participate were posted on the dialysis facility notice boards, along with the study protocol and consent information. Depending on center size, and therefore, staffing numbers, a total of four to eight participants was considered proportionately appropriate, allowing nurse participation within work time yet away from clinical activity.

Conduct of Focus Group Interviews One focus group interview was conducted at each dialysis center and lasted for 45 to 90 minutes. Participants were asked a series of semistructured questions using common interview prompts to facilitate exploration of additional elements, while still maintaining alignment with the study aims. Participants were asked about their familiarity with the algorithm and strategies used to prevent hypotension, including intervention practices. Participants were asked what elements of BP measurement they felt were most important for assessing and monitoring, and what they understood about MAP. Additional comments on usual practices, challenges, or concerns were explor-

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ed as they arose through conversation, and when appropriate, participants were asked to give examples or share stories to illustrate.

Data Analysis Quantitative audit data were initially entered in a Microsoft® Excel spreadsheet before being imported into IBM SPSS v22 for analysis; this included some demographic information. Chi-square analysis was conducted to compare the incidence of IDH recorded when UF was paused with the incidence when UF was not paused, including an odds ratio and confidence interval. Transcriptions of the audiorecorded data were read multiple times to enable the researchers to become very familiar with the data. The approach to analysis was adapted from Braun and Clark’s (2006) original methodology of data familiarization in four steps: from initial code generation, identification of overt theme groupings, further review of codes within groups, and ultimate theme definition.

Findings Audit Findings After using a list-wise deletion method to account for missing data, which amounted to 121 random missing treatments, data were analyzed for a total of 2,711 treatments from

236 patients across the five dialysis centers, representing 98% of patients across the five centers. Patients ranged in age from 20 to 92 years (M = 63.6, SD = 15.025), and 61% were over 60 years of age. Regarding comorbidities, 108 (47.7%) had a diagnosis of diabetes, 142 (62.5%) had a diagnosis of hypertension, and 78 (34.3%) had both diabetes and hypertension. Table 2 provides a comparative overview of the audit results for all 2,711 treatments across the five dialysis centers, showing progression for each potential stage of the pathway to final treatment outcome. Documentation of the MAP (on the worksheet, at least once) occurred in 1,872 (69%) treatments. Documentation did not always indicate if MAP calculations were factored in to decisions to follow the algorithm by instigating a UF pause or not. Twenty-seven hypotensive episodes were identified, representing 1% of the sample. Irrespective of MAP documentation, A-IDH was present in 335 treatments (12.3%). In 108 of these treatments, UF pause was performed in accordance with the algorithm. For these asymptomatic episodes, 103 (87%) experienced MAP recovery and completed uneventful dialysis treatment sessions; however, MAP recovery progressed to hypotension for one treatment. Of the 21 treatments in which the MAP did not recover, 17 treatments were unevent-


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ful, with patients remaining hypotensive but symptom-free, while four treatments progressed to hypotension. Of the total 108 treatments in which the UF was paused for A-IDH, five (4.6%) progressed to hypotension. Of the 227 patients who were classified as having asymptomatic hypotension in accordance with the algorithm and where no UF pause was performed, 125 (55%) had spontaneous MAP recovery. Of the 102 patients whose MAP did not recover (i.e., of those who remained asymptomatically hypotensive without intervention), 18 went on to become symptomatically unwell. These 18 accounted for 66% of the entire sample who developed IDH. The remainder who did not develop IDH remained asymptomatically hypotensive through to discharge. Finally, of the 2,376 treatments, four resulted in IDH with no prior evidence of A-IDH. There was considerable intercenter variation in compliance of the Intradialytic Hypotension Prevention Pathway algorithm, as determined by UF-pauses per A-IDH episodes. Table 2 indicates patient numbers and total treatments performed at each center in the four-week period. Algorithm compliance is presented by proportion (%) and number of UF pauses; the number of symptomatic IDH episodes despite and without UF pause per center are presented. Documentation of the MAP on worksheets varied from 31.7% to 93.2% between centers. Overall, the incidence of asymptomatic hypotension at each center ranged from 8.4% to 16.9% of all treatments. Center pathway compliance in implementing the 10-minute UF pause for recognized A-IDH ranged from 25% to 58.9% (mean 34%) of those treatments. Overall, instituting an ultrafiltration pause for asymptomatic hypotension decreased the odds of progression to symptomatic hypotensive episodes by 44%; however, this was not statistically significant (OR = 0.56, 95% CI = 0.20 to 1.56, χ21 = 1.25, p = 0.26).


Figure 2 Intradialytic Hypotension Prevention Pathway Conceptual Framework Understanding mean arterial pressure Championing use of pathway

Monitoring blood pressure Use of prior knowledge

Knowing the patient

Care collaboration

Dialysis challenges

Algorithm familiarity

Patient treatment concerns

Focus Group Interview Findings The convenience sample of 22 nurses consisted of 20 RNs (bachelor level) and two enrolled nurses (diploma level), with group sizes ranging from four to seven participants. Within the focus group data, four key themes emerged: algorithm familiarity, understanding the significance of mean arterial pressure, individualized patient assessment, and the importance of ongoing education. Within each theme, sub-themes were identified, and these were common and linked to each of the key themes. Subthemes related to the importance of knowing the patient, use of prior knowledge, collaboration of care, and dialysis challenges. A conceptual framework illustrating the four major, secondary, and tertiary subthemes as emerged from the data is displayed in Figure 2. Exemplars of participant responses are shown in Table 3.

Algorithm Familiarity The first question within all focus group interviews was posed to ascertain staff familiarity with the algorithm because it represented the working praxis of the pathway. Responses varied, but the majority of

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Individualized patient assessment Risk reduction: Significance of preventing deterioration Importance of ongoing education

participants across all groups had only limited exposure to it. One participant stated: “I’m not too familiar with it, but once I actually understand what it is, I might follow it.” This represents one of the two main barriers that emerged from the focus group interview data.

Contextual Understanding of MAP As the hallmark assessment and monitoring metric within the algorithm, an understanding of the significance of MAP was considered essential in both monitoring progression of patient clinical status and in assessing for instances of potential, relative hypotension. Participants were asked what they understood by “mean arterial pressure” and if they regularly consider its value. While most participants admitted outright that they did not know what it was, a few, particularly at the center where the algorithm was originally introduced, did. “So basically…it looks at the perfusion of your major organs, how well your organs are perfused.” Participants acknowledged the aspects of satellite dialysis whereby an acute procedure is performed upon chronically ill persons in an outpatient set-

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Algorithm Familiarity

Table 3 Thematic Quotation Exemplars

“Not here… I saw it at the study day, but not here.” “We mustn’t have had a champion. “ “Yes it started and just faded away.” “People were using it, but no one was driving it… I think it should be like when we are doing the rounds in the morning; we’re checking the patient… It’s one of the issues like, what’s the mean arterial pressure of the patient that becomes part of our expectation in part of the process of handover.” Individualized Patient Assessment

“We look back and…if you’re putting a patient on for the first time, I tend to look and refer back to the last few runs, what the blood pressure has been, and if it’s always high, I think. ‘Oh, it’s a trend; it’s not something new.’” “Because maybe it’s the starting point of their deteriorating, and we don’t realize, but when we look at the MAP and then we’re pausing, they are getting a chance to refill… It’s early detection of deterioration…before hypotensive symptoms, so they get a chance to refill and can recover from that.” “What is their blood pressure usually, what is their MAP usually, where do they sit at, you know – individualized care, so sometimes that all has to come in before we do anything.” “Again… a lot depends on how well you know the patient, the relationship you have…and how much they trust you, and you trust them. It’s a two-way process, actually.” “I think one of the nurses…just had the feeling that something was wrong... I didn’t notice him, but I was amazed at how she already…had that feeling… So you know, the longer you work here…you tend to pick up on little things… He was becoming hypotensive.” “We do the regular blood pressure monitoring, and then I usually use the previous run sheet as a reference for what the usual ranges would be for the patient…the trends of the blood pressure, if the blood pressure is going down, we would check more or alter the UF goals.” Understanding of Mean Arterial Pressure

“When I was on a surgical ward, we used to look at it (MAP) there… If the blood pressure was really low…but apart from that, no… I thought it was very good because even at (university name supplied), they’ve been very big on MAP, in our cardiac classes and other pathophysiology…they talk about MAP as it’s a big thing, and I was surprised when going on placements, it’s not done.” “You can imagine the refill happening when you pause… I think it’s advantageous to patients rather than to just keep dialysing even if they’re asymptomatic; there is a chance that not every patient’s got interstitial fluid sitting there to refill, but there is a higher chance to refill with a pause.” “I also noticed, I think in CCU, the doctors would usually write to keep the MAP above 60 or 70.” “[In ICU]…sometimes, someone might have a higher blood pressure, or their ranges might be out, but if you look at the MAP, it might still be 65 or 70. So you might not look entirely at the actual blood pressure, but you look at the MAP at the same time… and the doctors would say, ‘No, no, don’t worry about the blood pressure. Just look at the MAP.’ We’d aim for a MAP of 65 or 70.” “I think it’s more of an advantage in ICU, isn’t it? I feel more confident taking fluid off there... It’s like you know you’ll get the support.” “You can’t easily access their doctors… You are on your own… So the challenge is you are trying to do what you have to do on the machine and on the patient…but if you say, ‘Help, help,’ everyone comes and gives every kind of help that you need.” Importance of Ongoing Education

“In my experience… well, you cannot tell if your MAP is low. They [patients] will not understand what MAP is, so I think it’s best if we could educate the patient.” “Now there’s a big focus on clinical deterioration… The whole focus is on controlling and preventing that deterioration, rather than just attending to the patient… Early detection.”

“I think the only negative we get from patients is when they see us pause, they see that as an interruption to their treatment; they don’t see it as a safety precaution and part of their care. And they don’t see it as us responding to a possible clinical risk.”

“We tell them straight… All this is taken into consideration; it’s your life, and at the end of the day, we know. We are here to work together. We are here to help you. That’s all we can do.”

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Figure 3 Revised Intradialytic Hypotension Prevention Pathway Algorithm Calculate MAP on pre-dialysis blood pressure and record (worksheet)

At recognition of a low BP and MAP value: If MAP has decreased by more than 30mmHg from pre-dialysis MAP; OR if MAP value is less than 70 mmHG Pause ultrafiltration (UF = 0) for 10 minutes, then recheck BP If BP has improved and MAP ≥ 70 mmHg

Consider UF resumption with same or reduced goal

If BP and MAP have not improved

Discussion

Closely monitor patient’s BP, MAP, and condition Notes: Closely monitoring during low MAP suggests heightened awareness of patient condition for early recognition of deterioration, even if treatment parameters are only moderately adjusted.

ting. The process of removing several liters of fluid from the intravascular compartment in itself may cause profound hemodynamic instability, and the patient must recover adequately, after several hours of treatment, to be discharged home. Understanding what this means for a patient’s changing hemodynamic status depends partly upon algorithm utility and routine, as well as previous nursing exposure. For example, nurse participants with experience in other areas of acute care who may dialyze patients in intensive care were familiar with the concept of MAP and relayed some of their experiences.

Individualized Patient Assessment Much discussion centered on caring for the patient as an individual, thinking about usual assessment prac-


was expressed by participants in every focus group. It was acknowledged that the introduction of the algorithm was brief and only minimally supported. The majority of participants were honest about their overall uncertainty of its meaning and utility, but were interested and openly requested more information. “I think education [is important]…because we can all sit in an in-service and say that’s a great idea, I understand that, and we can go away, and 80% of that knowledge can leave.” Participants requested ongoing education for themselves and for patients, particularly because participants recognized clinician/patient collaboration as imperative to providing and tailoring treatment to patient needs to allow the best care possible.

tices, noticing patterns or trends, and the value of “knowing” each patient. Recognizing changes relative to individual patient parameters and to what degree changes were significant were discussed. “But it really depends on the actual patient because if they were hypertensive, then 100 is really too low for them…but for another patient it’s fine… It’s very subjective.” Participants discussed what individualized assessment meant in looking at what was usual for the patient, comparing BPs from previous hemodialysis treatments to the current treatment, looking for trends for that person, being alert to what the changes could mean, and initiating contingency strategies.

Importance of Ongoing Education Importance of education in supporting and facilitating algorithm use

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Recent interest in the significance of relative, asymptomatic hypotension during hemodialysis and the contribution of this to long-term mortality through hypoperfusive stunning of the brain, gut, and heart has confirmed the importance of A-IDH (Assimon & Flythe, 2015; Power, Charitaki, & Davenport, 2016; Ribitsch et al., 2015). While issues associated with symptomatic hypotension have been well explored, only a few previous publications have acknowledged the observation of decreasing MAP values prior to IDH (Barnas, Boer, & Koomans, 1999; Bradshaw & Bennett, 2015). Temporary pausing of UF in response to low MAP in patients without symptoms has been shown to decrease IDH (Bradshaw et al., 2011). However, findings from the audit and focus groups in this study suggest compliance with the Intradialytic Hypotension Prevention Pathway algorithm is compromised by several barriers, essentially by the ambiguity of MAP significance and participant familiarity to the pathway algorithm. An assumption was that if the MAP were documented, then compliance of the pathway would follow, yet this was not the case. Participants who had a working knowledge of the algo-

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rithm and of the value of MAP spoke positively of its potential to ameliorate progression to IDH; however, among other participants, this purpose and meaning was not clear. Participants’ recommendation to embed the algorithm into clinical routines, such as at patient handover, led to inclusion of calculation and recording of the pre-dialysis MAP value as standard practice (see Figure 3). This was designed to prompt monitoring of patient clinical status according to individual, person-centered needs, as is consistent with contemporary, international healthcare philosophy (World Health Organization [WHO], 2016), and in recognition of the imperative to reduce actual and potential clinical risk (Australian Commission on Safety and Quality in Healthcare [ACSQHC], 2012). Importantly, as indicated by focus group participants, improvement of algorithm compliance may occur when further education about MAP and its relevance to patient assessment is integrated into routine patient care. Much recent research indicates that introduction of innovative care strategies to the clinical setting requires facilitation from all strata of health service delivery, including leadership support, policy statements, feedback processes, opinion leaders, and education (Harvey & Kitson, 2015). Initial implementation of the algorithm intervention was suspected as being suboptimal. This was confirmed by study findings, which reinforced the notion that implementation of new practice innovations must be actively supported to ensure sustained embedding into routine practice. A secondary finding of this study indicated a symptomatic IDH incidence rate of only 1%, a value well below rates reported in other studies. Factors contributing to this low rate may include that hemodialysis treatment sessions in this network average five hours, and dialysate temperature is prescribed at 35.5˚ Celsius. Both longer treatment times and lower dialysate temperatures have been shown to improve overall morbidity

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of patients on hemodialysis (Davenport, 2011). Recently, Kuipers et al. (2016) performed a prospective study of 3,818 hemodialysis sessions and found that “dialysis hypotension according to the full EBPG definition occurred in only 6.7%” of sessions (p. 1). They acknowledged that different working definitions of hypotension are problematic, as other researchers also attest (Daugirdas, 2014; Flythe et al., 2014). The definition used in the present study incorporates recognition of asymptomatic or relative hypotension in relation to usual patient parameters as a potential indicator for IDH progression, and 18 of these 27 symptomatic episodes arose from previous A-IDH, as reported. Although the hypotension incidence rate was comparatively low, and statistical significance of UF pausing for asymptomatic hypotension was not shown, the reduced odds of symptomatic episodes following the intervention in accordance with the pathway remain clinically important. Two-thirds of those who developed symptomatic hypotension had not had the UF pause intervention performed. Yet under half who had episodes of A-IDH without a pause went on to complete uneventful treatment sessions. These 101 treatments represent patients discharged relatively hypotensive.

Strengths and Limitations A limitation of this study is that it only includes one health network in which this intervention was developed. Additionally, because the audit coding tool was contrived for this study, no construct validity or reliability testing was undertaken. The recording of all BP metrics, including MAP, also relied on handwritten worksheets because the hemodialysis machines used had no capacity for automatic recordings. A strength of the study is, however, that both quantitative and qualitative data sources were used to investigate uptake of the intervention and perceived value of IDH prevention through use of the pathway algorithm.

Conclusion Taking into consideration the burden of both symptomatic and asymptomatic hypotension for patients on hemodialysis, this study illuminated important barriers and facilitators that may inform strategies to expand and sustain implementation of the Intradialytic Hypotension Prevention Pathway algorithm. Additionally, this will offer dialysis clinicians enhanced assessment and monitoring skills by improving their understanding of the significance of changing MAP values in an individualized, person-centered context. Interview findings suggesting lack of algorithm familiarity, along with a desire for further nurse and patient information, reinforce the need for adequate education and support of new innovations into clinical practice. Subsequently, an updated algorithm has been incorporated into the organization’s clinical guidelines, and ongoing education has been provided for staff and information for patients. References Assimon, M.M., & Flythe, J.E. (2015). Rapid ultrafiltration rates and outcomes among hemodialysis patients: Re-examining the evidence base. Current Opinion in Nephrology and Hypertension, 24(6), 525-530. doi:10. 1097/mnh.0000000000000174 Australian Commission on Safety and Quality in Healthcare (ACSQHC). (2012). National Safety and Quality Health Service (NSQHS) standards. Sydney, Australia: Australian Government Retrieved from https://www. safetyandquality.gov.au/wp-content/ uploads/2011/09/NSQHS-Stand ards-Sept-2012.pdf Barnas, M.G., Boer, W.H., & Koomans, H.A. (1999). Hemodynamic patterns and spectral analysis of heart rate variability during dialysis hypotension. Journal of American Society of Nephrology, 10(12), 2577-2584. Bradshaw, W., & Bennett, P.N. (2015). Asymptomatic intradialytic hypotension: The need for pre-emptive intervention. Nephrology Nursing Journal, 42(5), 479-485.


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