Five myths about unacceptable behaviour in surgical education

Recent evidence of the occurrence of discrimination, bullying and sexual harassment in surgery and more generally within healthcare has led to widespread discussion about the effects of unacceptable behaviour in surgical education and practice. Despite accumulating evidence of the adverse effects of unacceptable behaviour in clinical practice, not only on health care professionals but on patient care and outcomes, many surgeons and other health care professionals continue to embrace false perceptions about appropriate professional behaviour, interactions and approaches to teaching within surgical departments and more generally within healthcare institutions. This article explores five misperceptions about unacceptable behaviour in surgical education and provides evidence that supports a change in practice.

Which ICU patients benefit most from inspiratory muscle training? Retrospective analysis of a randomized trial

Background: Inspiratory muscle training (IMT) increases inspiratory muscle strength and improves quality of life in intensive care unit (ICU) patients who have been invasively mechanically ventilated for ≥7 days. The purpose of this study was to identify which patients benefit most from IMT following weaning from mechanical ventilation. Methods: Secondary analysis of a randomized trial of supervised daily IMT in 70 patients (mean age 59 years) in a 31-bed ICU was carried out. Changes in inspiratory muscle strength (maximum inspiratory pressure, MIP) between enrolment and 2 weeks (ΔMIP) were analyzed to compare the IMT group (71% male) and the control group (58% male). Linear regression models explored which factors at baseline were associated with ΔMIP. Results: Thirty-four participants were allocated to the IMT group where baseline MIP was associated with an increase in ΔMIP, significantly different from the control group (p = 0.025). The highest ΔMIP was associated with baseline MIP ≥ 28 cmH₂O. In the IMT group, higher baseline quality of life (EQ5D) scores were associated with positive ΔMIP, significantly different from the control group (p = 0.029), with largest ΔMIP for those with EQ5D ≥ 40. Conclusions: Physiotherapists should target ICU patients with moderate inspiratory muscle weakness (MIP ≥28 cmH₂O) and moderate to high quality of life (EQ5D>40) within 48 h of ventilatory weaning as ideal candidates for IMT following prolonged mechanical ventilation.

Inspiratory muscle training for intensive care patients: A multidisciplinary practical guide for clinicians

OBJECTIVES

To describe a multidisciplinary approach to inspiratory muscle training (IMT) for patients in the intensive care unit (ICU).

BACKGROUND

Inspiratory muscle weakness is a known consequence of prolonged mechanical ventilation, and there is emerging evidence that specific IMT can ameliorate this weakness. However, IMT is not yet standard practice in many ICUs, possibly because of the wide variety of methods reported and a lack of published practical guidelines. While the optimal parameters for IMT are yet to be established, we share our detailed methodology which has been shown to be safe in selected ventilator-dependent patients and is the only approach which has been shown to increase quality of life in ICU patients.

METHODS

Patients who have experienced invasive mechanical ventilation for at least 7 days can commence IMT in either the ventilator-dependent phase or when weaned from mechanical ventilation. Intensity should be prescribed based on maximum inspiratory pressure, which is measurable through the tracheostomy or endotracheal tube via the ventilator or a respiratory pressure meter. Using a removable threshold device, we recommend high-intensity training (5 sets of 6 breaths at a minimum of 50% of maximum inspiratory pressure) performed once per day, supervised by the physiotherapist, with intensity increased daily such that patients can only just complete the 6th breath in each set.

RESULTS

Using this high-intensity approach, IMT is likely to improve not only inspiratory muscle strength but also quality of life in patients recently weaned from mechanical ventilation of 7 days' duration or longer. Effective IMT requires a multidisciplinary approach to maximise feasibility, with doctors, nurses, and therapists working closely to optimise conditions for successful IMT.

CONCLUSIONS

This multidisciplinary approach to implement IMT in ICU patients should assist clinicians in translating best-available evidence into practice, with the potential to enhance patient recovery.

Inspiratory muscle training to enhance recovery from mechanical ventilation: a randomised trial

Background

In patients who have been mechanically ventilated, inspiratory muscles remain weak and fatigable following ventilatory weaning, which may contribute to dyspnoea and limited functional recovery. Inspiratory muscle training may improve inspiratory muscle strength and endurance following weaning, potentially improving dyspnoea and quality of life in this patient group.

Methods

We conducted a randomised trial with assessor-blinding and intention-to-treat analysis. Following 48 hours of successful weaning, 70 participants (mechanically ventilated ≥7 days) were randomised to receive inspiratory muscle training once daily 5 days/week for 2 weeks in addition to usual care, or usual care (control). Primary endpoints were inspiratory muscle strength and fatigue resistance index (FRI) 2 weeks following enrolment. Secondary endpoints included dyspnoea, physical function and quality of life, post-intensive care length of stay and in-hospital mortality.

Results

34 participants were randomly allocated to the training group and 36 to control. The training group demonstrated greater improvements in inspiratory strength (training: 17%, control: 6%, mean difference: 11%, p=0.02). There were no statistically significant differences in FRI (0.03 vs 0.02, p=0.81), physical function (0.25 vs 0.25, p=0.97) or dyspnoea (−0.5 vs 0.2, p=0.22). Improvement in quality of life was greater in the training group (14% vs 2%, mean difference 12%, p=0.03). In-hospital mortality was higher in the training group (4 vs 0, 12% vs 0%, p=0.051).

Conclusions

Inspiratory muscle training following successful weaning increases inspiratory muscle strength and quality of life, but we cannot confidently rule out an associated increased risk of in-hospital mortality.

Trial registration number

ACTRN12610001089022, results.

Mobilization of intensive care patients: a multidisciplinary practical guide for clinicians

Objectives

To describe our experience and the practical tools we have developed to facilitate early mobilization in the intensive care unit (ICU) as a multidisciplinary team.

Background

Despite the evidence supporting early mobilization for improving outcomes for ICU patients, recent international point-prevalence studies reveal that few patients are mobilized in the ICU. Existing guidelines rarely address the practical issues faced by multidisciplinary ICU teams attempting to translate evidence into practice. We present a comprehensive strategy for safe mobilization utilized in our ICU, incorporating the combined skills of medical, nursing, and physiotherapy staff to achieve safe outcomes and establish a culture which prioritizes this intervention.

Methods

A raft of tools and strategies are described to facilitate mobilization in ICU by the multidisciplinary team. Patients without safe unsupported sitting balance and without ≥3/5 (Oxford scale) strength in the lower limbs commence phase 1 mobilization, including training of sitting balance and use of the tilt table. Phase 2 mobilization involves supported or active weight-bearing, incorporating gait harnesses if necessary. The Plan B mnemonic guides safe multidisciplinary mobilization of invasively ventilated patients and emphasizes the importance of a clearly articulated plan in delivering this valuable treatment as a team.

Discussion

These tools have been used over the past 5 years in a tertiary ICU with a very low incidence of adverse outcomes (<2%). The tools and strategies described are useful not only to guide practical implementation of early mobilization, but also in the creation of a unit culture where ICU staff prioritize early mobilization and collaborate daily to provide the best possible care.

Conclusion

These practical tools allow ICU clinicians to safely and effectively implement early mobilization in critically ill patients. A genuinely multidisciplinary approach to safe mobilization in ICU is key to its success in the long term.

What are the barriers to mobilizing intensive care patients?

PURPOSE

Recently there has been increased interest in early mobilization of critically ill patients. Proposed benefits include improvements in respiratory function, muscle wasting, intensive care unit (ICU), and hospital length of stay. We studied the frequency of early mobilization in our intensive care unit in order to identify barriers to early mobilization.

METHODS

A 4-week prospective audit of 106 patients admitted to a mixed medical-surgical tertiary ICU (mean age 60 ± 20 years, mean APACHE II score 14.7 ± 7.8) was performed. Outcome measures included number of patient days mobilized, type of mobilization, adverse events, and reasons for inability to mobilize.

RESULTS

Patients were mobilized on 176 (54%) of 327 patient days. Adverse events occurred in 2 of 176 mobilization episodes (1.1%). In 71 (47%) of the 151 patient days where mobilization did not occur, potentially avoidable factors were identified, including vascular access devices sited in the femoral region, timing of procedures and agitation or reduced level of consciousness.

CONCLUSIONS

Critically ill patients can be safely mobilized for much of their ICU stay. Interventions that may allow more patients to mobilize include: changing the site of vascular catheters, careful scheduling of procedures, and improved sedation management.

Protocol: inspiratory muscle training for promoting recovery and outcomes in ventilated patients (IMPROVe): a randomised controlled trial

INTRODUCTION

Inspiratory muscle weakness is a known consequence of mechanical ventilation and a potential contributor to difficulty in weaning from ventilatory support. Inspiratory muscle training (IMT) reduces the weaning period and increases the likelihood of successful weaning in some patients. However, it is not known how this training affects the residual inspiratory muscle fatigability following successful weaning nor patients' quality of life or functional outcomes.

METHODS AND ANALYSIS

This dual centre study includes two concurrent randomised controlled trials of IMT in adult patients who are either currently ventilator-dependent (>7 days) (n=70) or have been recently weaned from mechanical ventilation (>7 days) in the past week (n=70). Subjects will be stable, alert and able to actively participate and provide consent. There will be concealed allocation to either treatment (IMT) or usual physiotherapy (including deep breathing exercises without a resistance device). Primary outcomes are inspiratory muscle fatigue resistance and maximum inspiratory pressures. Secondary outcomes are quality of life (Short Form-36v2, EQ-5D), functional status (Acute Care Index of Function), rate of perceived exertion (Borg Scale), intensive care length of stay (days), post intensive care length of stay (days), rate of reintubation (%) and duration of ventilation (days).

ETHICS AND DISSEMINATION

Ethics approval has been obtained from relevant institutions, and results will be published with a view to influencing physiotherapy practice in the management of long-term ventilator-dependent patients to accelerate weaning and optimise rehabilitation outcomes.

TRIAL REGISTRATION NUMBER

ACTRN12610001089022.

A phase II randomised controlled trial of intensive insulin therapy in general intensive care patients

OBJECTIVE

To determine the safety and efficacy of an intensive insulin regimen compared with a conventional insulin regimen in general intensive care unit patients.

METHODS

A phase II, randomised controlled trial was conducted in 70 critically ill patients in a closed multidisciplinary ICU of a university-affiliated tertiary hospital. We assessed patient characteristics at baseline. Trial process measures included number of blood glucose measurements per day and number in target range, type and quantity of caloric intake, patient outcome and insulin dosing. The primary outcome was the median blood glucose concentration. Secondary outcome measures were incidence of hypoglycaemia (blood glucose level < 2.2 mmol/L), clinical sequelae of hypoglycaemia and hospital mortality.

RESULTS

Thirty-five patients were randomised to each of the two groups. More blood glucose samples were taken per day in the intensive insulin group (16 versus 9), but the number of samples in the normoglycaemic range was 48.5%, compared with 79.8% within the target glucose range in the conventional insulin group. The median (interquartile range) blood glucose concentrations in the intensive and conventional insulin therapy groups were 5.4 (5.1-5.7) mmol/L and 7.9 (7.2-9.0) mmol/L, respectively (difference, 2.5 mmol/L; P < 0.0001). Five patients (14.3%) in the intensive insulin therapy group became hypoglycaemic versus none in the conventional insulin therapy group. There were no detected clinical sequelae of hypoglycaemia.

CONCLUSION

The intensive insulin regimen was effective in achieving the target blood glucose concentration, with clear separation from the conventional insulin regimen. Although the incidence of hypoglycaemia was increased, there was no detectable harm.

Acute hepatic failure caused by an acute aortic dissection with cardiac tamponade: a case report

An acute cardiac tamponade from any cause may result in rapid deterioration of hepatic function in a previously healthy patient. We describe a case of an acute ascending aortic dissection that presented as acute hepatic failure, due to an acute cardiac tamponade and severe right heart failure. The differential diagnosis of the aetiology of acute liver failure is extensive and includes poisonings, vascular obstruction and sepsis, particularly on the background of decompensated liver disease. Many of these conditions are associated with hypotension. The acute presentation in our patient, combined with the lack of a characteristic history delayed the diagnosis of a proximal (type A) dissection with tamponade and subsequent hepatic failure. Severe right-sided heart failure as a result of conditions such as cardiac tamponade should be excluded in patients presenting with acute hepatic failure of unknown aetiology.

The limited utility of electrocardiography variables used to predict arrhythmia in psychotropic drug overdose

OBJECTIVE

The aim of the present study was to examine the relationship between serious arrhythmias in patients with psychotropic drug overdose and electrocardiography (ECG) findings that have been suggested previously to predict this complication.

METHODS

Thirty-nine patients with serious arrhythmias (ventricular tachycardia, supraventricular tachycardia or cardiac arrest) after tricyclic antidepressant overdose or thioridazine overdose were compared with 117 controls with clinically significant overdose matched to each case for the drug ingested. These patients with psychotropic drug overdose had presented for treatment to the Department of Clinical Toxicology, Newcastle and to the Princess Alexandra Hospital, Brisbane. The heart rate, the QRS width, the QTc and QT intervals, the QT dispersion, and the R wave and R/S ratios in aVR on the initial ECGs were compared in cases and controls.

RESULTS

The cases had taken dothiepin (16 patients), doxepin (six patients), thioridazine (five patients), amitriptyline (five patients), nortriptyline (three patients), imipramine (one patient) and a combination of dothiepin and thioridazine (three patients). In 20 of the 39 patients with arrhythmias, the arrhythmia had been a presumed ventricular tachycardia. Of the other 19 patients, 15 patients had a supraventricular tachycardia, two patients had cardiac arrests (one asystole, one without ECG monitoring) and two patients had insufficient data recorded to make classification of the arrhythmias possible. The QRS was >/= 100 ms in 82% of cases but also in 76% of controls. QRS >/= 160 ms had a sensitivity of only 13% and occurred in 2% of controls. QRS > 120 ms, QTc > 500 and the R/S ratio in aVR appeared to have a stronger association with the occurrence of arrhythmia: QRS > 120 ms (odds ratio [OR], 3.56; 95% confidence interval [CI], 1.46-8.68), QTc > 500 (OR, 3.07; 95% CI, 1.33-7.07), and R/S ratio in aVR > 0.7 (OR, 16; 95% CI, 3.47-74). Excluding thioridazine overdoses and performing the analysis for tricyclic antidepressant overdoses alone gave increased odds ratios for QRS > 120 ms (OR, 4.83; 95% CI, 1.73-13.5) and QTc > 500 (OR, 4.5; 95% CI, 1.56-13) but had little effect on that for the R/S ratio in aVR > 0.7 (OR, 14.5; 95% CI, 3.10-68).

CONCLUSION

ECG measurements were generally weakly related to the occurrence of arrhythmia and should not be used as the sole criteria for risk assessment in tricyclic antidepressant overdose. The frequently recommended practice of using either QRS >/= 100 ms or QRS >/= 160 ms to predict arrhythmias is not supported by our study. R/S ratio in aVR > 0.7 was most strongly related to arrhythmia but had estimated positive and negative predictive values of only 41% and 95%, respectively. The use of these specific predictors in other drug overdoses is not recommended without specific studies.

Cortical and medullary betaine-GPC modulated by osmolality independently of oxygen in the intact kidney

Renal osmolyte concentrations are reduced during reflow following ischemia. Osmolyte decreases may follow oxygen depletion or loss of extracellular osmolality in the medulla. Image-guided volume-localized magnetic resonance (MR) microspectroscopy was used to monitor regional osmolytes during hyposmotic shock and hypoxia in the intact rat kidney. Alternate spectra were acquired from 24-microl voxels in cortex and medulla of the isolated perfused kidney. There was a progressive decrease in the combined betaine-glycerophosphorylcholine (GPC) peak intensity of 21% in cortex and 35% in medulla of normoxic kidneys between 60 and 160 min after commencing perfusion. Hypoxia had no significant effect on the betaine-GPC peak intensity in cortex or medulla, despite a dramatic reduction in tubular sodium, potassium, and water reabsorption. The results suggest that cortical and medullary intracellular osmolyte concentrations depend on osmotically regulated channels that are insensitive to oxygen and dissociated from the oxygen-dependent parameters of renal function, the fractional excretion of sodium, the fractional excretion of potassium, and urine-to-plasma inulin concentration ratio.

Regional proton nuclear magnetic resonance spectroscopy differentiates cortex and medulla in the isolated perfused rat kidney

Volume-localized proton nuclear magnetic resonance spectroscopy was used as an assay of regional biochemistry in the isolated perfused rat kidney. This model eliminated artifacts caused by respiratory and cardiac motion experienced in vivo. Immersion of the kidney under its venous effluent reduced the susceptibility artifacts evoked by tissue-air interfaces. The rapid acquisition with relaxation enhancement imaging sequence was used for scout imaging. This gave excellent spatial resolution of the cortex, outer medulla, and inner medulla. Spectra were then acquired in 10 minutes using the volume-selective multipulse spectroscopy sequence from voxels with a volume of approximately 24 microL located within the cortical or medullary regions. Spectral peaks were assigned by the addition of known compounds to the perfusion medium and by comparison with spectra of protein-free extracts of cortex and medulla. The medullary region spectra were characterized by signals from the osmolytes betaine, glycerophosphorylcholine, and inositol. The spectra from the cortex were more complex and contained lesser contributions from osmolytes.