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.

Magnitude and meaningfulness of change in SF-36 scores in four types of orthopedic surgery

Background: The Medical Outcomes General Health Survey (SF-36) is a widely used health status measure; however, limited evidence is available for its performance in orthopedic settings. The aim of this study was to examine the magnitude and meaningfulness of change and sensitivity of SF-36 subscales following orthopedic surgery.

Methods: Longitudinal data on outcomes of total hip replacement (THR, n = 255), total knee replacement (TKR, n = 103), arthroscopic partial meniscectomy (APM, n = 74) and anterior cruciate ligament reconstruction (ACL, n = 62) were used to estimate the effect sizes (ES, magnitude of change) and minimal detectable change (sensitivity) at the group and individual level. To provide context for interpreting the magnitude of changes in SF-36 scores, we also compared patients' scores with age and sex-matched population norms. The studies were conducted in Sweden. Follow-up was five years in THR and TKR studies, two years in ACL, and three months in APM.

Results: On average, large effect sizes (ES≥0.80) were found after orthopedic surgery in SF-36 subscales measuring physical aspects (physical functioning, role physical, and bodily pain). Small (0.20–0.49) to moderate (0.50–0.79) effect sizes were found in subscales measuring mental and social aspects (role emotional, vitality, social functioning, and mental health). General health scores remained relatively unchanged during the follow-up. Despite improvements, post-surgery mean scores of patients were still below the age and sex matched population norms on physical subscales. Patients' scores on mental and social subscales approached population norms following the surgery. At the individual level, scores of a large proportion of patients were affected by floor or ceiling effects on several subscales and the sensitivity to individual change was very low.

Conclusion: Large to moderate meaningful changes in group scores were observed in all SF-36 subscales except General Health across the intervention groups. Therefore, in orthopedic settings, the SF-36 can be used to show changes for groups in physical, mental, and social dimensions and in comparison with population norms. However, SF-36 subscales have low sensitivity to individual change and so we caution against using SF-36 to monitor the health status of individual patients undergoing orthopedic surgery.

Patient outcomes in the acute revovery phase following robotic-assisted prostate surgery : a prospective study

Background: Robotic-assisted minimally invasive urologic surgery was developed to minimise surgical trauma resulting in quicker recovery. It has many potential benefits for patients with localised prostate cancer over traditional surgical techniques without taking a risk with the oncological result.

Objectives: To report the specific surgical outcomes for the first Australian cohort of patients with localised prostate cancer that had undergone robotic-assisted radical prostatectomy (RARP) surgery. The outcomes represent the acute (in-hospital) recovery phase and include pain, length of stay (LOS), urinary catheter management and wound management.

Methods: Prospective descriptive survey of 214 consecutive patients admitted to a large metropolitan private hospital in Melbourne, Australia between December 2003 and June 2005. Patients had undergone RARP surgery for localised prostate cancer. Data were collected from the medical records and through interview at the time of discharge. Descriptive statistics were used to describe the frequency and proportion of outcomes. Patient characteristics were tabulated using cross tabulation frequency distribution and measures of central tendency.

Results: The findings from this study are highly encouraging when compared to outcomes associated with traditional surgical techniques. Transurethral catheter duration (median 7 days (IQ range 2)) and LOS (median 3 days (IQ range 2)) were considerably reduced. While operation time (median 3.30 h (IQ range 1.07)) was marginally reduced we would expect a further reduction as the surgical team becomes more skilled.

Conclusion: The findings from this study contribute to building a comprehensive picture of patient outcomes in the acute (in-hospital) recovery phase for a cohort of Australian patients who have undergone RARP surgery for localised prostate cancer. As such, these findings will provide valuable information with which to plan care for patients’ who undergo robotic-assisted surgery.

Oxygen delivery to patients after cardiac surgery : a medical record audit

OBJECTIVE: To describe how intensive care nurses manage the administration of supplemental oxygen to patients during the first 24 hours after cardiac surgery.
METHODS: A retrospective audit was conducted of the medical records of 245 adult patients who underwent cardiac surgery between 1 January 2005 and 31 May 2008 in an Australian metropolitan hospital. Physiological data (oxygen saturation measured by pulse oximetry and respiratory rate) and intensive care unit management data (oxygen delivery device, oxygen flow rate and duration of mechanical ventilation) were collected at hourly intervals over the first 24 hours of ICU care.
RESULTS: Of the 245 patients whose records were audited, 185 were male; mean age was 70 years (SD, 10), and mean APACHE II score was 17.5 (SD, 5.14). Almost half the patients (122, 49.8%) were extubated within 8 hours of ICU admission. The most common oxygen delivery device used immediately after extubation was the simple face mask (214 patients, 87%). Following extubation, patients received supplemental oxygen via, on average, two different delivery devices (range, 1-3), and had the delivery device changed an average of 1.38 times (range, 0-6) during the 24 hours studied. Twenty-two patients (9%) received non-invasive ventilation or high-flow oxygen therapy, and 16 (7%) experienced one or more episode of hypoxaemia during mechanical ventilation. A total of 148 patients (60%) experienced one or more episodes of low oxygenation or abnormal respiratory rate during the first 24 hours of ICU care despite receiving supplemental oxygen.
CONCLUSION: These findings suggest that the ICU environment does not protect cardiac surgical patients from suboptimal oxygen delivery, and highlights the need for strategies to prompt the early initiation of interventions aimed at optimising blood oxygen levels in cardiac surgical patients in the ICU.

Exploratory surgery of the female psyche

The thesis explores the visual narrative concerning a journey of empowerment for women. To enable the journey to advance the inquiry is directed into two areas. The first area is female gender, which is argued to be socially constructed and implicit in the marginalisation of women in western society. The second area is ‘feminine authority’, which is gained by developing an understanding and acceptance of the characteristics which have historically been considered as belonging to the feminine. Granting these characteristics agency would recognise their authority and assist in the elevation of the female to a position of equality in western society. Beginning from a feminist position, the research supported the belief that the female is marginalised in western society. It also confirmed the notion that empowerment and authority can be attained by women if they actively pursue the following; • Explore their own psychology beyond the existing socially constructed gender roles. • Develop an understanding of their feminine self by applying Jung's theories on individuation and archetypes. • Expose the underlying patriarchal influence in western epistemology and science by challenging existing deeply held cultural and scientific beliefs and by actively contributing as feminists to the areas of epistemology and science. Archetypal myths of the ‘feminine’ have developed from an androcentric position. They enforce and perpetuate gender imbalance which contributes to the disenfranchisement of women in western society, ‘Individuation’ is a process in which a person explores aspects of themselves to bring forth parts of their unconscious into their conscious mind in an attempt to gain a deeper understanding of themselves. As a consequence the consciousness develops closer links with archetypal memories which assists the exploration. The ‘true feminine’ is the feminine not restricted or defined by the dominant androcentric view. Knowledge of the feminine empowers women to address the marginalisation of the female in western society and assists in the process of gaining female authority. This enquiry also investigated the four stages of female psychological development with regard to patriarchal influences. Of particular importance is the second stage of psychological development where the female identifies with historically perceived inferior characteristics of the female. This is when she rejects her connections with the primacy of female power and her deep connections with nature which were inherited from archaic times. It is at this stage that she absorbs the myths associated with western patriarchal society which effectively disempower her. Western epistemology, with its emphasis on ‘objective’ investigation and empiricism contributes to the support for and promotion of ‘inferior’ female gender. This type of investigation is brought into question when areas of research into primates and human evolutionary theory is shown to develop from an androcentric view. Western knowledge has associations with power and justice and power is commonly associated with dominance. Regard for ‘truth’ and ‘absolute’ can be viewed as key elements in the support for knowledge and its associations with power. Knowledge has historically maintained suppression of individual experience which promotes a universalised account. This suppression of beliefs other than the dominant authority maintains the existing dominant social structure. Foucault's view of the genderised or inscribed body alerts us to areas where dominance, resistance and power play a part in maximising masculine power and control. Gender becomes an instrument of power within the existing patriarchal structure. Gender, knowledge and power are identified as areas obstructing female empowerment. Part 3 of this exegesis examines the imagery which embodies the visual narrative. Particularly, the harlequin image, its historical background and connections with ancient mythology including reference to Jungian psychology. The harlequin image is developed sequentially in the earlier black and white drawings on paper. These drawings contained a female figure which was often placed in juxtaposition with a Venus or goddess image, reference was also made to ‘eve’ and the ‘siren’. These elements provided the framework which enabled the harlequin image to emerge and evolve. The narrative developed with an understanding of the ‘feminine’ aspects of the psyche which resulted in the harlequin acquiring the elevated authority of a goddess. The Harlequin evolved from my need for symbolic representation of the female psyche. It represents contradiction and dualism. It is a composition of opposites, reflects masculine and feminine traits, the dark and light of the conscious and unconscious mind, it houses both comic and sinister elements, is a trickster and menace. The costume, colours and patterns are expressive elements conducive to fragmentation and layering within the composition of the paintings. Jung examined the harlequin in Picasso's paintings. He concluded that as Picasso drew on his inner experiences the harlequin became important as a symbol; it was a pictorial representation from the unconscious psyche. It travelled freely from the conscious to the unconscious and represented the masculine and feminine, chthonian and apollonian. The final painting in the series, a triptych, completes the narrative and stands alone as a salutatory work. It unites the series by combining existing compositional devices and technique while making reference to imagery from previous works, ‘The Three Graces Victorious’, expresses the authority of the feminine. It completes a victorious stage of a journey where the harlequin is empowered by archaic memories and knowledge of the psyche. The feminine is hailed, elevated and venerated. Other elements which assist in expressing the visual narrative are; colour, technique and influence. Colour is explored and its use as an emotive devise in expressionism. Paul Klee's writing on the use of colour and it's symbolic meaning and Julia Kristeva's investigation on colour from a psychoanalytic and semiotic view are also discussed. To indicate influences and connections within my oeuvre, reference is also made to the following: Jasper Johns' for his use of imagery in his ‘Four Seasons’ series with it's reference to a journey of maturation and Louise Bourgeois' work which deals with issues of gender, memories and past journeys. Although ‘The Three Graces Victorious’; the concluding painting for the investigation is celebratory and represents a finality to the thesis, it points to further areas that impede feminine development and need future examination. Reference is made to a continuation of the exploratory journey by plotting the Harlequin/Goddesses future directions. Although the Harlequin/Goddess is empowered with newly acquired authority, her future journey does not need to be bound by mathematics or limited by rationality. She does not require power to dominate or gender structures to subjugate, but requires limitless boundaries and contexts. The Harlequin/Goddess's future journey is not fixed.

Variation in age and physical status prior to total knee and hip replacement surgery : a comparison of centers in Australia and Europe

Objective : To investigate whether variation exists in the preoperative age, pain, stiffness, and physical function of people undergoing total knee replacement (TKR) and total hip replacement (THR) at several centers in Australia and Europe.
Methods : Individual Western Ontario and McMaster Universities Osteoarthritis Index data (range 0-100, where 0 = best and 100 = worst) collected within 6 weeks prior to primary TKR and THR were extracted from 16 centers (n = 2,835) according to specified eligibility criteria. Analysis of covariance was used to evaluate differences in pain, stiffness, and physical function between centers, with adjustment for age and sex.
Results : There was marked variation in the age of people undergoing surgery between the centers (TKR mean age 67-73 years; F[6,1004] = 4.21, P < 0.01, and THR mean age 63-72 years; F[14,1807] = 7.27, P < 0.01). Large differences in preoperative status were observed between centers, most notably for pain (TKR adjusted mean pain 52.5-61.1; F[6,1002] = 4.26, P < 0.01, and THR adjusted mean pain 49.2-65.7; F[14,1802] = 8.44, P < 0.01) and physical function (TKR adjusted mean function 52.7-61.4; F[6,1002] = 5.27, P < 0.01, and THR adjusted mean function 53.3-71.0; F[14,1802] = 6.71, P < 0.01). Large effect sizes (up to 0.98) reflect the magnitude of variation between centers and highlight the clinical relevance of these findings.
Conclusion : The large variations in age and preoperative status indicate substantial differences in the timing of joint replacement across the centers studied, with potential for compromised surgical outcomes due to premature or delayed surgery. Possible contributing factors include patient preferences, the absence of concrete indications for surgery, and the capacity of the health care systems.