Hemodynamic team decision making in the cardiac surgical intensive care context

Purpose
The purpose of this study was to explore the extent and sources of variability of critical care nurses’ hemodynamic decision making as a function of contextual factors in the immediate 2-hour period after cardiac surgery.

Methods
A qualitative exploratory design with observation and interview was used. Eight critical care nurses were observed on different occasions in clinical practice for a 2-hour period. A brief interview immediately followed each observation to clarify observation data.

Findings
Analysis of the data revealed that patient management decisions were made both by individual nurses and by a team of nurses and health professionals. Team decision making (TDM) is described in this study as integrated or non-integrated and refers to an intra-professional nursing team. During displays of integrated TDM, the primary nurse, who was assigned to care for the patient, made most hemodynamic decisions and nurses who assisted the primary nurse deferred decisions. During displays of non-integrated TDM, nurses assisting the primary nurse assumed responsibilities for most patient-related decisions. Non-integrated TDM occurred more frequently when inexperienced cardiac surgical intensive care nurses were in the role of primary nurse, whereas integrated TDM was more common among experienced cardiac surgical intensive care nurses.

Conclusions
This observed variability can occur in multiple ways and in hemodynamic decision making has implications for patient outcomes as behaviors of non-integrated TDM led to nurses sensing a loss of control of patient management.

Postoperative pulmonary dysfunction in adults after cardiac surgery with cardiopulmonary bypass: clinical significance and implications for practice

Postoperative pulmonary complications are the most frequent and significant contributor to morbidity, mortality, and costs associated with hospitalization. Interestingly, despite the prevalence of these complications in cardiac surgical patients, recognition, diagnosis, and management of this problem vary widely. In addition, little information is available on the continuum between routine postoperative pulmonary dysfunction and postoperative pulmonary complications. The course of events from pulmonary dysfunction associated with surgery to discharge from the hospital in cardiac patients is largely unexplored. In the absence of evidence-based practice guidelines for the care of cardiac surgical patients with postoperative pulmonary dysfunction, an understanding of the path ophysiological basis of the development of postoperative pulmonary complications is fundamental to enable clinicians to assess the value of current management interventions. Previous research on postoperative pulmonary dysfunction in adults undergoing cardiac surgery is reviewed, with an emphasis on the pathogenesis of this problem, implications for clinical nursing practice, and possibilities for future research.

The haemodynamic status of cardiac surgical patients in the initial 2-h recovery period

Background
Critical care nurses caring for cardiac patients in the immediate postoperative period continually make decisions about the implications and treatment of their patients' haemodynamic status.

Aim
The aim of this study was to describe the haemodynamic status of patients on admission to critical care and over the 2-h period following cardiac surgery.

Methods
A quantitative, descriptive design was used. Data were collected using non-participant observation and an observation tool. The sample consisted of 38 patients.

Results
Analysis of data revealed the dynamic nature of the haemodynamic status of postoperative cardiac patients. On admission, 60% of patients (n = 23) were haemodynamically unstable. The instability in these patients (n = 23) was due to hypotension (34%), bleeding (21%) and hypoxaemia (18%). During the 2-h recovery period, 55% of patients were hypotensive, 16% of patients had low cardiac output syndrome and 16% of patients had low systemic vascular resistance (SVR) syndrome. Twenty-one percent of patients experienced bleeding complications. Shivering was a clinically significant problem in terms of occurrence (23%) and duration (X = 45, S.D. = 30 min). Twenty-nine percent of patients (n = 11) had a profound deterioration in haemodynamic status, necessitating urgent interventions.

Conclusion
Haemodynamic parameters indicate that 95% of patients in this study were haemodynamically unstable at some time during the initial 2-h recovery period. These findings inform resourcing decisions by organisations and have implications for nurses' assessment and interventional haemodynamic decision making.

Haemodynamic instability after cardiac surgery: nurses` perceptions of clinical decision-making

Background. Cardiac surgical patients are distinguished by their potential for instability in the early postoperative period, highly invasive haemodynamic monitoring technologies and unique clinical presentations as a result of undergoing cardiopulmonary bypass. Little is known about nurses’ perceptions of assuming responsibility for such patients. An nderstanding of nurses’ perceptions may identify areas of practice that can be improved and assist in determining the adequacy of current decision supports.

Aim. The aim of this study was to describe critical care nurses’ perceptions of assuming responsibility for the nursing management of cardiac patients in the initial two-hour postoperative period. Design. An exploratory descriptive study based on naturalistic decision-making.

Methods. Thirty-eight nurses were interviewed immediately following a two-hour observation of their clinical practice. Content analysis and a systematic thematic analysis process called ‘Framework’ were used to analyse the interview transcripts.

Results. Nurses described their perceptions of managing patients in terms of how they felt about making decisions for complex cardiac surgical patients and in terms of how clinical processes unique to the admission phase impacted their decision-making. Nurses felt either daunted or stimulated and challenged when making decisions. Nurses identified handover from anaesthetists, settling in procedures and forms of
collegial assistance as important processes that impacted their decision-making.

Conclusion. Nurses’ previous experiences with similar patients influenced how they felt about making decisions during the initial two-hour postoperative period, but did not alter their views about processes important for patient safety during this time. Relevance to clinical practice. Feelings expressed by nurses in this study highlight the need for clinical supervision and appropriate allocation of resources during the immediate recovery period after cardiac surgery. Nurses identified ways to improve clinical processes that impacted their decision-making during the immediate recovery of cardiac surgical patients.

The influence of patient complexity and nurses` experience on haemodynamic decision-making following cardiac surgery

Critical care nurses’ haemodynamic decision-making in the immediate postoperative cardiac surgical context is complex. To optimise patient outcomes, nurses of varying levels of experience are required to make complex decisions rapidly and accurately. In a dynamic clinical context such as critical care, the quality of such decision-making is likely to vary considerably. The aim of this study was to describe variability of nurses’ haemodynamic decision-making in the 2-hour period after cardiac surgery as a function of interplay between decision complexity, nurses’ levels of experience, and the support provided. A descriptive study based on naturalistic decision-making was used. Data were collected using continuous non-participant observation of clinical practice for a 2-hour period and follow-up interview. Purposive sampling was used to recruit 38 nurses for inclusion in the study. The quality of nurses’ decision-making was influenced by interplay between the complexity of patients’ haemodynamic presentations, nurses’ levels of cardiac surgical intensive care experience, and the form of decision support provided by nursing colleagues. Two factors specifically influenced decision-making quality: nurses’ utilisation of evidence for practice and the experience levels of both nurses and their colleagues. The findings have implications for staff resourcing decisions and postoperative patient management, and may be used to inform nurses’ professional development and education.

Issues in the provision of nursing care to people undergoing cardiac surgery who also have type 2 diabetes

There has been little investigation of the issues associated with caring for patients presenting for cardiac surgery with a comorbid diagnosis of diabetes although there is some evidence that the diabetes management is suboptimal. This study aimed to identify issues that patients and cardiac specialist nurses experience with the provision of inpatient services for people undergoing cardiac surgery who also have type 2 diabetes. A qualitative interpretive design, using individual interviews with patients and nurses, provided data about some of these issues. The study found that nurses had high levels of confidence in their cardiac care but little confidence in diabetes management. Patients described concerns about their diabetes care and treatment regimens. A 'typical journey' for a person with diabetes undergoing cardiac surgery was identified. The findings support the need to build increased capacity in specialist nurses to support diabetes care as a secondary diagnosis.

Financial, family, and social factors impacting on cardiac rehabilitation attendance

Background
Attendance in phase 2 cardiac rehabilitation program after acute myocardial infarction is poor.

Objective
To identify and explore the demographic factors that influence peoples’ decisions to attend cardiac rehabilitation programs.

Methods
A descriptive-interpretive design was used. Semi-structured interviews were conducted with 10 people post infarction in Victoria, Australia after their first scheduled appointment to attend outpatient cardiac rehabilitation. The interview transcripts were thematically analysed.

Results
The perceived relevance of cardiac rehabilitation related to the context of people’s lives, namely their financial, family and social situation, and how important program outcomes were seen to be relevant to this context.

Conclusion
The findings of this study suggest that there are a proportion of people unlikely to attend outpatient cardiac rehabilitation programs following an AMI despite encouragement to attend. It may be unrealistic to aim for 100% referral and uptake into cardiac rehabilitation programs and therefore an inappropriate endpoint by which to evaluate such programs.

Long-term risk factor control after a cardiac rehabilitation programme

This study examined the hypothesis that Phase II cardiac rehabilitation participants (CRP) had better long-term risk factor control, self-rated perception of health and return to work rates than non-participants (NP) between 18 and 36 months post myocardial infarction (MI). It was a comparative study in a 550 bed hospital.

Approximately half of both groups did not achieve a total cholesterol (TC) of 5.5mmol/L or less. Compared with NP, CRP were significantly more likely to have a TC<=6.5mmol/L (7% vs. 28%) (p=0.006). NP with TC>6.5mmol/L were significantly less likely to be on treatment (p=0.002). CRP were more likely to regularly exercise than NP (79% vs. 61%) (p=0.038). The success rate for blood pressure targets, return to work rates and self-rated perception of health were similar in both groups.

In conclusion, CRP had better long-term control of some risk factors than NP. The study provides comparative longer term patient outcomes after an Australian cardiac rehabilitation (CR) programme and forms the basis for further outcome measurement.

Metabolic and cardiac outcomes after acute myocardial infarction

The original DIGAMI protocol recommended using intravenous insulin to manage myocardial infarction from first presentation followed by subcutaneous insulin for 3 months in patients with diabetes. This paper describes the metabolic and cardiac outcomes and barriers to implementing a protocol designed to match the DIGAMI principles across our emergency and cardiology departments. Patients managed using the revised DIGAMI protocol achieved better blood glucose control and had fewer reinfarcts than those managed without insulin. The major barrier to using the protocol appeared to be staff fear of causing hypoglycaemia.

Variable definitions: implications for the prediction of pulmonary complications after adult cardiac surgery

Aim: The aim of this paper was to review the implications that variable definitions have for the prediction of post-operative pulmonary complications after cardiac surgery.

Method: A review of the literature from 1980 to 2002. Selected studies demonstrated an original attempt to examine multivariate associations between pre, intra or post-operative antecedents and pulmonary outcomes in patients undergoing coronary artery bypass grafting (CABG). Reports that described the validation of established clinical prediction rules, testing interventions or research conducted in non-human cohorts were excluded from this review.

Results: Consistently, variable factor and outcome definitions are combined for the development of multivariate prediction models that subsequently have limited clinical value. Despite being prevalent there are very few attempts to examine post-operative pulmonary complications (PPC) as endpoints in isolation. The trajectory of pulmonary dysfunction that precedes complications in the post-operative context is not clear. As such there is little knowledge of post-operative antecedents to PPC that are invariably excluded from model development.

Conclusion: Multivariate clinical prediction rules that incorporate antecedent patient and process factors from the continuum of cardiovascular care for specific pulmonary outcomes are recommended. Models such as these would be useful for practice, policy and quality improvement.

Cardiac rehabilitation in south west Victoria : factors influencing attendance

Background : The benefits of cardiac rehabilitation (CR) programs are well established. Despite these benefits their utilisation remains sub-optimal, with an average of 24% of eligible cardiac patients attending outpatient CR programs across Victoria.
Aims & rationale/Objectives : The objectives of this study were to (a) identify local barriers and enablers to the uptake of hospital-based CR programs, and (b) identify preferred alternatives for the delivery of CR.
Methods : Six hospital-based CR programs within the region agreed to participate in this study. A consecutive series of patients referred to the programs were surveyed by the CR coordinators to identify the local barriers and enablers influencing CR program attendance. In addition, focus groups with CR participants and health professionals were conducted at two hospitals in order to ascertain their views on current programs, suggestions for improvements and alternative methods of CR delivery.
Principal findings : Survey data was obtained from a total of 97 patients referred to the CR programs during the study period, 27 (28%) females and 70 (72%) males. Main reasons given for CR non-attendance were related to distance to travel, cost of petrol, reliance on others for transport and lack of interest or motivation to attend. For CR attenders, main enablers included encouragement by family, medical and other health professionals, and having someone else to drive them. Suggestions for alternative methods of CR delivery included more programs in outlying communities, home and GP based programs, telephone support and a patient manual or workbook.
Discussion : The results of this study provide valuable information for designing strategies to increase utilisation of existing CR programs as well as pilot testing alternative modes of CR program delivery for cardiac patients in rural areas unable to access hospital-based CR.
Implications : These findings suggest that many of the barriers identified could be addressed by a more creative use of existing resources and the provision of CR services in primary care settings.
Presentation type : Poster

Exploring the barriers and enablers to attendance at rural cardiac rehabilitation programs

Objective: The objectives of this study were to: (i) identify local barriers and enablers to the uptake of hospital-based cardiac rehabilitation (CR) programs, and (ii) identify preferred alternatives for the delivery of CR.

Design: A questionnaire administered by local CR coordinators and focus groups facilitated by the research team.

Setting: Six regional hospitals in south-west Victoria offering hospital-based CR programs.

Participants: Patients and their carers referred to and eligible for local CR programs; health professionals working within local CR programs.

Main outcomes measures: CR attendees and decliners demographics, patient and health professional perceived factors which contribute to enabling hospital-based CR attendance, patient and health professional perceived barriers to CR attendance, and receptiveness and preferences for alternative modes of CR delivery.

Results: This study identified distance to travel to hospital-based CR programs the only statistically significant factor in determining uptake of CR. Easy access to transport (63%) and to a lesser extent family support (49%) and work flexibility (43%) were the primary enablers to attendance. Of the 97 study participants, 38% were receptive to alternative CR methods such as programs in outlying communities, evening facility-based programs, home and GP based programs, telephone support and a patient manual/workbook.

Conclusions: The results of this study provide valuable information for designing strategies to increase utilisation and improve patient acceptability of existing hospital-based CR programs. It provides a basis for pilot testing alternative modes of CR program delivery for cardiac patients in rural areas unable to access hospital-based CR.

Skin temperature as a noninvasive marker of haemodynamic and perfusion status in adult cardiac surgical patients : an observational study

Objective
Foot temperature has long been advocated as a reliable noninvasive measure of cardiac output despite equivocal evidence. The aim of this pilot study was to investigate the relationship between noninvasively measured skin temperature and the more invasive core-peripheral temperature gradients (CPTGs), against cardiac output, systemic vascular resistance, serum lactate, and base deficit.

Research methodology
The study was of a prospective, observational and correlational design. Seventy-six measurements were recorded on 10 adults postcardiac surgery. Haemodynamic assessments were made via bolus thermodilution. Skin temperature was measured objectively via adhesive probes, and subjectively using a three-point scale.

Setting
The study was conducted within a tertiary level intensive care unit.

Results
Cardiac output was a significant predictor for objectively measured skin temperature and CPTG (p = .001 and p = .004, respectively). Subjective assessment of skin temperature was significantly related to cardiac output, systemic vascular resistance, and serum lactate (p < .001, respectively).

Conclusions
These results support the utilisation of skin temperature as a noninvasive marker of cardiac output and perfusion. The use of CPTG was shown to be unnecessary, given the parallels in results with the less invasive skin temperature parameters. A larger study is however required to validate these findings.

Intrinsic resistance of female hearts to an ischemic insult is abrogated in primary cardiac hypertrophy

Important sex differences in cardiovascular disease outcomes exist, including conditions of hypertrophic cardiomyopathy and cardiac ischemia. Studies of sex differences in the extent to which load-independent (primary) hypertrophy modulates the response to ischemia-reperfusion (I/R) damage have not been characterized. We have previously described a model of primary genetic cardiac hypertrophy, the hypertrophic heart rat (HHR). In this study the sex differences in HHR cardiac function and responses to I/R [compared to control normal heart rat (NHR)] were investigated ex vivo. The ventricular weight index was markedly increased in HHR female (7.82 ± 0.49 vs. 4.80 ± 0.10 mg/g; P < 0.05) and male (5.76 ± 0.22 vs. 4.62 ± 0.07 mg/g; P < 0.05) hearts. Female hearts of both strains exhibited a reduced basal contractility compared with strain-matched males [maximum first derivative of pressure (dP/dtmax): NHR, 4,036 ± 171 vs. 4,258 ± 152 mmHg/s; and HHR, 3,974 ± 160 vs. 4,540 ± 259 mmHg/s; P < 0.05]. HHR hearts were more susceptible to I/R (I = 25 min, and R = 30 min) injury than NHR hearts (decreased functional recovery, and increased lactate dehydrogenase efflux). Female NHR hearts exhibited a significantly greater recovery (dP/dtmax) post-I/R relative to male NHR (95.0 ± 12.2% vs. 60.5 ± 9.4%), a resistance to postischemic dysfunction not evident in female HHR (29.0 ± 5.6% vs. 25.9 ± 6.3%). Ventricular fibrillation was suppressed, and expression levels of Akt and ERK1/2 were selectively elevated in female NHR hearts. Thus the occurrence of load-independent primary cardiac hypertrophy undermines the intrinsic resistance of female hearts to I/R insult, with the observed abrogation of endogenous cardioprotective signaling pathways consistent with a potential mechanistic role in this loss of protection.