Sarah Smailes

Noninvasive Positive Pressure Ventilation in burns

OBJECTIVE Acute respiratory failure is a common complication of the severely burn-injured patient. Endotracheal intubation and mechanical ventilation is associated with a high rate of complications. Noninvasive Positive Pressure Ventilation (NIPPV) has been shown to be as effective as conventional ventilation in improving gas exchange and is associated with fewer complications with patients in acute hypercapnic and hypoxaemic respiratory failure. We report our experience with NIPPV in 30 burn patients. METHOD The records of all burn patients from 1998 to 2000, where NIPPV was used as part of their management at the St. Andrews Centre for Plastic Surgery and Burns, were reviewed. RESULTS Mean age was 47.56 years (range 12-81). Nine patients were female. Mean burn size was 24.4% total body surface area (TBSA) (range 3-54). Inhalation injury was confirmed in eight cases. A positive diagnosis of pneumonia was made in 29 patients. The mean PaO(2)/FiO(2) ratio prior to institution of NIPPV was 28.98Kpa (range 8.75-52). Intermittent Positive Pressure Breathing (IPPB) was the most common ventilatory mode employed (25 patients) and the face mask was the most used interface (18 cases). Twenty-two patients (74%) avoided endotracheal intubation and their respiratory function continued to improve after NIPPV was discontinued. One patient (3%) died and seven patients (23%) were reintubated. Three out of the seven were electively reintubated for burns surgery. CONCLUSION In burn-injured patients with acute respiratory failure, NIPPV appears to be effective in supporting respiratory function such that endotracheal intubation can be avoided in most cases.

Tracheostomy in burns patients revisited

OBJECTIVE The use of tracheostomy in burns patients has been controversial. A retrospective study was conducted to assess the use, complications and outcome of tracheostomy in ventilated adult burns patients. METHODS Data was collected retrospectively regarding the extent of injury in each patient, the indication for tracheostomy, and outcome in terms of length of stay, days of mechanical ventilation, airway and pulmonary complications and survival. Patients were followed until discharge from the unit or death. RESULTS Comparing patients who received tracheostomy to those who had translaryngeal intubation showed similar age distribution and no significant difference in the total burn surface area (TBSA). The use of tracheostomy was significantly higher in patients with TBSA >60%. Inhalation injury was significantly higher and mean probability of survival (ABSI), significantly lower in patients receiving tracheostomy. Duration of mechanical ventilation, length of stay in HDU/ITU and the incidence of pulmonary sepsis were significantly higher in tracheostomy group patients. However, there was no significant difference in mortality between the two groups. CONCLUSION Burn survivors with TBSA >60% are more likely to undergo repeated surgery and have burns to the head and neck region, therefore increasing the requirement for tracheostomy. Tracheostomy is a safe procedure with minimal perioperative complications. Late complications in this patient group may be related to duration of intubation and mechanical ventilation and the presence of an airway burn. Tracheostomy was associated with a higher prevalence of chest infection. We suspect that the cause of this is multifactorial, possibly due to a higher incidence of inhalation injury, greater burn size and prolonged mechanical ventilation in this group.

Cough strength, secretions and extubation outcome in burn patients who have passed a spontaneous breathing trial.

The aim of this study was to develop a clinical prediction model to inform decisions about the timing of extubation in burn patients who have passed a spontaneous breathing trial (SBT). Rapid shallow breathing index, voluntary cough peak flow (CPF) and endotracheal secretions were measured after each patient had passed a SBT and just prior to extubation. We used multiple logistic regression analysis to identify variables that predict extubation outcome. Seventeen patients failed their first trials of extubation (14%). CPF and endotracheal secretions are strongly associated with extubation outcome (p<0.0001). Patients with CPF ≤60 L/min are 9 times as likely to fail extubation as those with CPF >60 L/min (risk ratio=9.1). Patients with abundant endotracheal secretions are 8 times as likely to fail extubation compared to those with no, mild and moderate endotracheal secretions (risk ratio=8). Our clinical prediction model combining CPF and endotracheal secretions has strong predictive capacity for extubation outcome (area under receiver operating characteristic curve=0.96, 95% confidence interval 0.91-0.99) and therefore may be useful to predict which patients will succeed or fail extubation after passing a SBT.

Percutaneous dilational and surgical tracheostomy in burn patients: Incidence of complications and dysphagia

The aim of this study is to evaluate the incidence of complications and dysphagia in relation to the timing of tracheostomy and tracheostomy technique in 49 consecutive adult burn patients. We analysed prospectively collected data. Bronchoscopy was used to diagnose tracheal stenosis and a modified Evans blue dye test was used to diagnose dysphagia. Eighteen patients received a percutaneous dilatational tracheostomy (PDT) and thirty-one patients received an open surgical tracheostomy (OST). Eight patients developed significant complications (16%) following tracheostomy, there is no difference in the incidence of complications; post op infection, stoma infection or tracheal stenosis between PDT and OST groups. Patients with full thickness neck burn who developed complications had a tracheostomy significantly earlier following autografting (p=0.05). Failed extubation is associated with dysphagia (p=0.02) whereas prolonged intubation and ventilation prior to tracheostomy independently predicts dysphagia (p=0.03). We conclude that there is no difference in the complication rates for PDT and OST in our burn patients. We recommend early closure of neck burns and tracheostomy through fully adherent autograft or at least 10 days after grafting to reduce stomal infections. For patients with no neck burn, we support early tracheostomy to reduce the likelihood of dysphagia.

The incidence and outcome of extubation failure in burn intensive care patients.

To identify the incidence and outcome of extubation failure in patients with burn. Retrospective cohort study in a tertiary burn intensive care unit. A review of the casenotes of 132 consecutive adult patients with burn admitted between 2001 and 2005, and requiring mechanical ventilation for >24 hours, was undertaken. Sixty-seven patients underwent extubation and entered data analyses. Extubation failure was defined as reintubation within 48 hours. The outcomes of interest were incidence and cause of extubation failure, duration of mechanical ventilation (DMV), length of stay (LOS), and mortality. The patients who succeeded and failed extubation were similar in terms of age, sex, burn size (P = .3), and incidence of inhalation injury (P = .1). Of 67 planned extubations, 20 (30%) failed. DMV (22.5 vs. 4 days; P < .001), intensive care LOS (1.20 vs. 0.41 days/% burn; P < .001), and hospital LOS (1.90 vs. 1.18 days/ % burn; P < .003) were significantly longer in reintubated patients when compared with those who extubated successfully. Extubation outcome, burn size, and age provided the best predictive model for patient outcome (P = .02), but extubation outcome was the only predictor that operated individually (P = .05). The aetiology of extubation failure in 15 (75%) patients was poor pulmonary toilet. The incidence of extubation failure in this homogenous population of patients with burn is higher than general intensive care patients (30% vs. 4–23%). The DMV, lengths of intensive care, and hospital stay are significantly longer in patients who failed extubation. In addition to burn size and age, extubation outcome is an important predictor of intensive care mortality. The indication for reintubation in most patients is poor airway clearance.

One world one burn rehabilitation standard

According to the World Health Organization (WHO) burns are a huge global health problem resulting in death and devastation to those who survive large burns as they are faced with significant functional limitations that prevent purposeful and productive living. Members of the International Society for Burn Injuries (ISBI) Rehabilitation Committee conducted a needs assessment survey in order to characterize how burn rehabilitation is implemented worldwide and how the international burn rehabilitation community can help improve burn rehabilitation in identified geographic locations which need assistance in rehabilitating burn survivors successfully. The results of this survey indicated that poor and in some cases resource limited environments (RLEs) around the world seem to lack the financial, educational and material resources to conduct burn rehabilitation successfully. It appears that there are vast discrepancies in the areas of education, training and capacity to conduct research to improve the care of burn survivors as evidenced by the variation in responses between the RLEs and developed countries around the globe. In some cases, the problem is not knowledge, skill and ability to practice burn rehabilitation, but rather having the resources to do so due to financial difficulties.

Smoke inhalation increases intensive care requirements and morbidity in paediatric burns

Burn survival has improved with advancements in fluid resuscitation, surgical wound management, wound dressings, access to antibiotics and nutritional support for burn patients. Despite these advancements, the presence of smoke inhalation injury in addition to a cutaneous burn still significantly increases morbidity and mortality. The pathophysiology of smoke inhalation has been well studied in animal models. Translation of this knowledge into effectiveness of clinical management and correlation with patient outcomes including the paediatric population, is still limited. We retrospectively reviewed our experience of 13 years of paediatric burns admitted to a regional burns intensive care unit. We compared critical care requirements and patient outcomes between those with cutaneous burns only and those with concurrent smoke inhalation injury. Smoke inhalation increases critical care requirements and mortality in the paediatric burn population. Therefore, early critical care input in the management of these patients is advised.

Development and implementation of prospective outcome monitoring in a regional burns service using cumulative sum (CUSUM) techniques

INTRODUCTION Real-time monitoring of mortality in burns units has the potential to immediately mark when mortality rates are significantly higher or lower than predicted. Rapid feedback from targeted internal audit allows early intervention, to reinforce positive practices, and improve systems where outcomes are unsatisfactory. This is the first study to describe prospective use of cumulative sum (CUSUM) methodology in mortality monitoring outside of cardiac surgery. METHODS An eight-year retrospective study of mortality was performed on all admissions to a regional burns intensive care unit in the UK. Risk-adjusted CUSUM charts, variable life adjusted displays (VLADs) and zeroed VLADs were produced to track mortality against that predicted by the Belgium burns score. The same techniques were implemented prospectively for one year (76 admissions) using the Osler modification of the Baux score for risk adjustment. RESULTS Internal audit would have been triggered on nine occasions using zeroed VLAD monitoring in the retrospective study. The Belgium score overpredicts mortality in the elderly. Internal audit was triggered for better than predicted outcomes on two occasions in the prospective study. DISCUSSION This study describes a successful design for an early-warning system to monitor outcomes in a burns intensive care setting.

Burns ITU admissions: length of stay in specific levels of care for adult and paediatric patients.

Prediction of total length of stay (LOS) for burns patients based on the total burn surface area (TBSA) is well accepted. Total LOS is a poor measure of resource consumption. Our aim was to determine the LOS in specific levels of care to better inform resource allocation. We performed a retrospective review of LOS in intensive treatment unit (ITU), burns high dependency unit (HDU) and burns low dependency unit (LDU) for all patients requiring ITU admission in a regional burns service from 2003 to 2011. During this period, our unit has admitted 1312 paediatric and 1445 adult patients to our Burns ITU. In both groups, ITU comprised 20% of the total LOS (mean 0.23±0.02 [adult] and 0.22±0.02 [paediatric] days per %burn). In adults, 33% of LOS was in HDU (0.52±0.06 days per %burn) and 48% (0.68±0.06 days per %burn) in LDU, while in children, 15% of LOS was in HDU (0.19±0.03 days per %burn) and 65% in LDU (0.70±0.06 days per %burn). When considering Burns ITU admissions, resource allocation ought to be planned according to expected LOS in specific levels of care rather than total LOS. The largest proportion of stay is in low dependency, likely due to social issues.

Evaluation of the spontaneous breathing trial in burn intensive care patients

BACKGROUND The extubation failure rate in our burn patients is 30%. OBJECTIVE To evaluate the influence of the 30 min spontaneous breathing trial on extubation outcome in burn patients. METHODS A prospective, observational study in a burn intensive care unit. All adult patients requiring mechanical ventilation for >24h and meeting the inclusion criteria underwent a 30 min spontaneous breathing trial (SBT). Extubation was undertaken after a successful SBT. RESULTS Of 49 planned extubations, 9 failed (18%), much lower than the 30% extubation failure rate identified prior to the implementation of the SBT. The duration of ventilation was significantly shorter (p=0.04) in the patients who passed a SBT and those who failed extubation were significantly older (p=0.003). The logistic regression analysis identified that age independently predicted extubation outcome. Patients who failed extubation, after a successful SBT, had a significantly longer duration of ventilation (p=0.0001) and ITU length of stay (p=0.001). CONCLUSIONS The incidence of extubation failure was much lower and the duration of ventilation significantly shorter in patients who were extubated after a successful SBT. These findings support the use of the SBT in burn patients. Age independently predicts extubation outcome in burn patients who have passed a SBT.