A.R. Manara

Donation after circulatory death

Donation after circulatory death (DCD) describes the retrieval of organs for the purposes of transplantation that follows death confirmed using circulatory criteria. The persisting shortfall in the availability of organs for transplantation has prompted many countries to re-introduce DCD schemes not only for kidney retrieval but increasingly for other organs with a lower tolerance for warm ischaemia such as the liver, pancreas, and lungs. DCD contrasts in many important respects to the current standard model for deceased donation, namely donation after brain death. The challenge in the practice of DCD includes how to identify patients as suitable potential DCD donors, how to support and maintain the trust of bereaved families, and how to manage the consequences of warm ischaemia in a fashion that is professionally, ethically, and legally acceptable. Many of the concerns about the practice of both controlled and uncontrolled DCD are being addressed by increasing professional consensus on the ethical and legal justification for many of the interventions necessary to facilitate DCD. In some countries, DCD after the withdrawal of active treatment accounts for a substantial proportion of deceased organ donors overall. Where this occurs, there is an increased acceptance that organ and tissue donation should be considered a routine part of end-of-life care in both intensive care unit and emergency department.

Reduction in mortality from severe head injury following introduction of a protocol for intensive care management

BACKGROUND To determine the effect of an intensive care management protocol on the intensive care unit (ICU) and hospital mortality of severely head-injured patients, we designed a longitudinal observational study of all patients admitted with a head injury between 1992 and 2000. METHODS A computerized patient database was used to identify all patients with severe head injury admitted to the ICU at Frenchay Hospital, Bristol, UK: a tertiary referral centre for the clinical neurosciences. We compared the ICU and hospital mortality and length of stay in patients before and after implementation of a protocol for their ICU management in 1997. RESULTS Implementation of the protocol was associated with a significant reduction in ICU mortality from 19.95% to 13.5% (odds ratio 0.47; 95% CI 0.29-0.75), and in hospital mortality from 24.55% to 20.8% (odds ratio 0.48; 95% CI 0.31-0.74). This was achieved despite a significant increase in the median APACHE II score (14 vs 18) of patients admitted after implementation of the protocol. The median ICU and hospital length of stay remained constant over the study period. CONCLUSIONS The introduction of an evidence-based protocol to guide the ICU management of patients with severe head injury has been associated with a significant reduction in both ICU and hospital mortality.

Role of therapeutic hypothermia in improving outcome after traumatic brain injury: a systematic review

This systematic review delineates the effect of primary therapeutic hypothermia (PTH) (initiated on presentation of the patient) on both mortality and neurological outcome in patients with traumatic brain injury. The safety profile of the therapy is also assessed. A systematic search of the following databases was performed: MEDLINE, EMBASE, Zetoc database of conference proceedings, the Cochrane Database of Systematic Reviews, and the clinicaltrials.gov website, up to July 28, 2011. Relevant journals were hand-searched for further articles and reference lists were checked against the retrieved results for additional resources. The retrieved results were filtered for randomized controlled trials in English where systemic hypothermia was applied for ≥ 12 h in the treatment arm and outcome was assessed at a minimum of 3 months. Randomized controlled trials were assessed for quality of evidence using the GRADE system. Eighteen randomized controlled trials (1851 patients) were identified. The overall relative risk of mortality with PTH when compared with controls was 0.84 [95% confidence interval (CI)=0.72-0.98] and of poor neurological outcome was 0.81 (95% CI=0.73-0.89). However, when only high-quality trials were analysed, the relative risks were 1.28 (95% CI=0.89-1.83) and 1.07 (95% CI=0.92-1.24), respectively. Hypothermia was associated with cerebrovascular disturbances on rewarming and possibly with pneumonia in adult patients. Given the quality of the data currently available, no benefit of PTH on mortality or neurological morbidity could be identified. The therapy should therefore only be used within the confines of well-designed clinical trials.

Sensitivity of near infrared spectroscopy to cerebral and extra-cerebral oxygenation changes is determined by emitter-detector separation.

Objective. To examine the effect of two emitter-detector separations (2.7 and 5.5 cm) on the detection of changes in cerebral and extra-cerebral tissue oxygenation using near infrared spectroscopy (NIRS). Methods. Two NIR detectors were placed on the scalp 2.7 and 5.5 cm from a single NIR emitter. Changes in deoxyhaemoglobin (HHb), oxyhaemoglobin (O2Hb),oxidised cytochrome C oxidase (Cyt) and total haemoglobin (tHb) were recorded from each detector during the induction of cerebral oligaemia (transition from hypercapnia to hypocapnia) and scalp hyperaemia (following release of a scalp tourniquet). Results. Cerebral oligaemia (mean decrease in middle cerebral artery blood flow velocity of 44%) induced by a mean reduction in end tidal CO2 of 18 mmHg was accompanied by a significant increase in the spectroscopic signal for HHb and a decrease in the O2Hb signal. The signal change per unit photon path length detected at 5.5 cm was significantly greater for HHb (p = 0.007) than that detected at 2.7 cm. In contrast, the increase in all chromophores detected at 5.5 cm during scalp hyperaemia was significantly less than that detected at 2.7 cm (p < 0.001). Conclusions. The differing sensitivity of the proximal and distal channels to changes in cerebral and extra-cerebral oxygenation is compatible with theoretical models of NIR light transmission in the adult head and may provide a basis for spatially resolving these changes. The optimal emitter-detector separation for adult NIRS requires further investigation and may differ between individuals.

Experiences in the development of non-heart beating organ donation scheme in a regional neurosciences intensive care unit†

BACKGROUND In the UK demand for organ transplantation continues to outstrip supply and one strategy aimed at reversing this trend is the introduction of non-heart beating donor (NHBD) schemes. In this paper we describe our experience after the introduction of the NHBD scheme at a regional neuroscience intensive care unit (ICU) that also provides general intensive care. METHODS We describe the steps taken to establish the scheme and present our results from the time of its implementation in July 2002 until March 2007. RESULTS Of the 100 patients whom we referred to the transplant co-ordinators, 71 were identified as potential NHBDs and of these 29 went on to become actual donors (conversion rate of 40.8%). Fifty-six kidneys were retrieved and 53 successfully transplanted. In addition, two livers were retrieved but subsequently found to be unsuitable for transplantation, while eight pancreas were retrieved and used for islet cell research. The serum creatinine at 1 yr demonstrates that there is no significant difference between transplanted kidney function from NHBDs and heart-beating donors (HBDs). CONCLUSIONS We believe that by establishing the NHBD organ donation scheme we are able to fulfil the wishes of more patients who have indicated that they would like to donate their organs while increasing the availability of solid organs for transplantation. With careful preparation, audit, and communication our experience demonstrates that the NHBD scheme can be successfully introduced in an ICU and expanded to other ICUs in a region.

Treating Delayed Gastric Emptying in Critical Illness Metoclopramide, Erythromycin, and Bedside (Cortrak) Nasointestinal Tube Placement

BACKGROUND We describe experience using the Cortrak nasointestinal feeding tube and prokinetics in critically ill patients with delayed gastric emptying. METHODS Patient cohorts fed via a Cortrak electromagnetically guided nasointestinal tube (EGNT) or 14 French-gauge nasogastric tube plus prokinetics were retrospectively compared. RESULTS Of 69 EGNT placements in 62 patients, 87% reached the small intestine. The median percentage of the enteral nutrition goal increased from 19% pre-EGNT to 80%-100% between days 1 and 10 post-insertion and was greater than in 58 patients prescribed metoclopramide (40%-87%: days 1-2, 5-7, P < or = .018) or 38 patients prescribed erythromycin (48%-98%; days 1 and 5, P < .0084). Up to day 10, the cumulative feeding days lost were lower for EGNT (1.06) than for metoclopramide (2.6, P < .02) or erythromycin (3.1, P < .02). The EGNT group had a lower use of prokinetics and lower treatment cost. CONCLUSION Most bedside EGNT placements succeed and, compared to nasogastric feeding plus prokinetics, increase enteral nutrition delivery and reduce both cumulative feeding days lost and prokinetic use.

Controlled non-heart beating organ donation: neither the whole solution nor a step too far

While many intensive care clinicians in the UK continue to express significant concerns regarding controlled non‐heart beating organ donation, others are involved in established programmes that make an increasingly significant contribution to the total number of cadaveric donations each year. The successful introduction of a controlled non‐heart beating organ donation programme requires local resolution of any apparent ethicolegal obstacles to the process, with specific attention needing to be given to three areas: the potential conflict of interest between decision making over futility and any subsequent approach regarding organ donation; a belief that it may be unlawful to adjust in any way an end of life care pathway in order to allow donation to take place, and, finally, an uncertainty over how soon after cardiac death organ retrieval can begin. It is proposed that recent changes in legislation provide, through an emphasis on patient autonomy and best interests, a solid ethicolegal foundation for donation after cardiac death.

The role of steroids following major trauma

This article reviews the indications and evidence for the administration of steroids to patients who have suffered significant trauma. Uncontroversial indications are rare. In spinal cord injury steroids are often given but the practical benefits are questionable. The case for treatment in head injury is unproven. Consideration should be given to treating all those patients who develop acute respiratory distress syndrome (ARDS), although treatment should be deferred to the later (fibroproliferative) stages. The role of steroids in sepsis is complicated and, although steroid administration can have dramatic effects on vasopressor requirements, convincing evidence for mortality reduction is not available.