Extubation failure in pediatric intensive care incidence and outcomes

Emergency tracheal intubation of severely head-injured children: changing daily practice after implementation of national guidelines

OBJECTIVE

To report daily practice of scene emergency tracheal intubation performed by physicians and changes induced by implementation of national guidelines, with special attention to rapid sequence induction (RSI) and control of assisted ventilation.

DESIGN

Observational study.

SETTING

Pediatric intensive care unit of a university hospital.

PATIENTS

A total of 296 children (age, 2-15 yrs old) referred to our center for severe traumatic brain injury (Glasgow Coma Scale score of ≤ 8), with spontaneous cardiac rhythm.

INTERVENTIONS

Scene RSI practice by field physicians was compared before (n = 188), and after (n = 108) publication of national guidelines. Emergency tracheal intubation conditions, RSI use, immediate complications, assisted ventilation efficiency on blood gases measurements upon arrival, and, in the later period, physician's knowledge, and observance to published guidelines were analyzed.

MEASUREMENTS AND MAIN RESULTS

After publication of guidelines, tracheal intubation was performed at the scene in 100% of the cases (vs. 88%, p = .05); RSI practice was more standardized, with an increased use of succinylcholine (10% to 80%, p = .0001), and a concomitant decreased use of nondepolarizing muscle relaxant (20% vs. 0%, p = .005), and opioids (70% vs. 36%, p = .05). Recommended RSI protocol (etomidate and succinylcholine) was effectively used by 64% of the physicians (vs. 2.8%, p = .001), and rate of immediate complications upon tube insertion (mainly cough reflex) decreased to 8% (vs. 25%, p = .0015). Scene emergency tracheal intubation, when ordered, resulted in a 100% success rate and adequate oxygenation within the two groups. Despite increasing the use of portable capnograph in the later period, Paco2 was measured outside the tight target range (35-40 torr, 4.6-5.3 kPa) in 70% of the cases upon arrival.

CONCLUSIONS

Scene emergency tracheal intubation was effectively performed by trained careproviders in children with traumatic brain injury. Implementation of guidelines led to a more standardized practice of RSI, decreased rate of immediate complications, but insufficient control of Paco2 during transport.

An institutional experience with epidural analgesia in children and young adults undergoing cardiac surgery

BACKGROUND

Allowing spontaneous respiration after cardiac surgery eliminates complications related to mechanical ventilation and optimizes cardiopulmonary interaction. Epidural analgesia has been proposed to promote early extubation after cardiac surgery.

OBJECTIVE

To identify the characteristics of patients with epidural analgesia and safety profiles with respect to the timing of extubation following cardiac surgery.

DESIGN AND METHOD

A retrospective chart review of patients who underwent cardiac surgery during a 5-year period. Demographic, procedural, and perioperative variables were analyzed to investigate factors that affect the timing of extubation.

RESULTS

A total of 750 records were reviewed. The patients' median age was 12 months, and 52% were infants (<1 year). Seventy-five percent of the patients utilized cardiopulmonary bypass. The study population was classified into three groups according to the timing of extubation: 66% were extubated in the operating room or upon arrival at the PICU (Immediate), 15% were extubated within 24 h (mean, 10.8 h; 95% CI, 9.0-12.6) (Early), and 19% were extubated after 24 h (Delayed). For the Immediate and Early groups, multivariate logistic regression identified young age, increased cross-clamp time, and inotrope score as independent risk factors for the need for mechanical ventilation. Postextubation respiratory acidosis (mean P(a)CO(2), 50 mmHg; 95% CI, 49-51) was well tolerated by all patients. There were no neurologic complications related to the epidural technique.

CONCLUSION

Epidural analgesia in children undergoing cardiac surgery provides stable analgesia without complications in our experience.

Children with corrected or palliated congenital heart disease on home mechanical ventilation

Infants and children with surgically corrected or palliated congenital heart disease (CHD) are at risk for chronic respiratory failure, necessitating home mechanical ventilation (HMV) via tracheostomy. However, very little data exists on this population or their outcomes. We conducted a retrospective chart review of all children with CHD enrolled in the Childrens Hospital Los Angeles HMV program between 1994 and 2009. Data were collected on type of heart lesion, surgeries performed, number of failed extubations, timing of tracheostomy, mortality, length of time on HMV, weaning status, associated co-morbidities, and Risk Adjusted classification for Congenital Heart Surgery (RACHS-1) category. Thirty-five children were identified; six with single ventricle anatomy, who received palliative procedures. Twenty-three (66%) patients are alive; 8 (23%) living patients have been weaned off HMV. Twelve (34%) patients are deceased. The incidence of mortality for single ventricle patients was 50%, and only one of the surviving children has received final palliation and weaned off HMV. Eight of nine patients (89%) with a RACHS score > or =4 died, and none have been weaned off of HMV. The 5-year survival for all CHD HMV patients was 68%; 90% for patients with RACHS < or =3; and 12% for patients with score > or =4. Children with more complex lesions, as demonstrated by single ventricle physiology or greater RACHS scores, had higher mortality rates and less success weaning off HMV. This case series suggests that caregivers should give serious consideration to the type of heart defect as they advise families considering HMV in children with CHD.

Non invasive ventilation after extubation in paediatric patients: a preliminary study

Background

Non-invasive ventilation (NIV) may be useful after extubation in children. Our objective was to determine postextubation NIV characteristics and to identify risk factors of postextubation NIV failure.

Methods

A prospective observational study was conducted in an 8-bed pediatric intensive care unit (PICU). Following PICU protocol, NIV was applied to patients who had been mechanically ventilated for over 12 hours considered at high-risk of extubation failure -elective NIV (eNIV), immediately after extubation- or those who developed respiratory failure within 48 hours after extubation -rescue NIV (rNIV)-. Patients were categorized in subgroups according to their main underlying conditions. NIV was deemed successful when reintubation was avoided. Logistic regression analysis was performed in order to identify predictors of NIV failure.

Results

There were 41 episodes (rNIV in 20 episodes). Success rate was 50% in rNIV and 81% in eNIV (p = 0.037). We found significant differences in univariate analysis between success and failure groups in respiratory rate (RR) decrease at 6 hours, FiO₂ at 1 hour and PO₂/FiO₂ ratio at 6 hours. Neurologic condition was found to be associated with NIV failure. Multiple logistic regression analysis identified no variable as independent NIV outcome predictor.

Conclusions

Our data suggest that postextubation NIV seems to be useful in avoiding reintubation in high-risk children when applied immediately after extubation. NIV was more likely to fail when ARF has already developed (rNIV), when RR at 6 hours did not decrease and if oxygen requirements increased. Neurologic patients seem to be at higher risk of reintubation despite NIV use.

Tension-time index as a predictor of extubation outcome in ventilated children

RATIONALE

Indices that assess the load on the respiratory muscles, such as the tension-time index (TTI), may predict extubation outcome.

OBJECTIVES

To evaluate the performance of a noninvasive assessment of TTI, the respiratory muscle tension time index (TTmus), by comparison to that of the diaphragm tension time index (TTdi) and other predictors of extubation outcome in ventilated children.

METHODS

Eighty children (median [range] age 2.1 yr [0.15-16]) admitted to pediatric intensive care units at King's College and St Mary's Hospitals who required mechanical ventilation for more than 24 hours were studied.

MEASUREMENTS AND MAIN RESULTS

TTmus, maximal inspiratory pressure, respiratory drive, respiratory system mechanics, and functional residual capacity using a helium dilution technique, the rapid shallow breathing and CROP indices (compliance, rate, oxygenation, and pressure) indexed for body weight were measured and standard clinical data recorded in all patients. TTdi was measured in 28 of the 80 children using balloon catheters. Eight children (three in the TTdi group) failed extubation. TTmus (0.199 vs. 0.09) and TTdi (0.157 vs. 0.07) were significantly higher in children who failed extubation. TTmus greater than 0.18 (n = 80) and TTdi greater than 0.15 (n = 28) had sensitivities and specificities of 100% in predicting extubation failure. The other predictors performed less well.

CONCLUSIONS

Invasive and noninvasive measurements of TTI may provide accurate prediction of extubation outcome in mechanically ventilated children.

Higher pulmonary dead space may predict prolonged mechanical ventilation after cardiac surgery

Children undergoing congenital heart surgery are at risk for prolonged mechanical ventilation and length of hospital stay. We investigated the prognostic value of pulmonary dead space fraction as a non-invasive, physiologic marker in this population. In a prospective, cross-sectional study, we measured pulmonary dead space fraction in 52 intubated, pediatric patients within 24 hr postoperative from congenital heart surgery. Measurements were obtained with a bedside, non-invasive cardiac output (NICO) monitor (Respironics Novametrix, Inc., Wallingford, CT). Median pulmonary dead space fraction was 0.46 (25-75% IQR 0.34-0.55). Pulmonary dead space fraction significantly correlated with duration of mechanical ventilation and length of hospital stay in the entire cohort (r(s) = 0.51, P = 0.0002; r(s) = 0.51, P = 0.0002) and in the subset of patients without residual intracardiac shunting (r(s) = 0.45, P = 0.008; r(s) = 0.49, P = 0.004). In a multivariable logistic regression model, pulmonary dead space fraction remained an independent predictor for prolonged mechanical ventilation in the presence of cardiopulmonary bypass time and ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen (OR 2.2; 95% CI 1.14-4.38; P = 0.02). The area under the receiver operator characteristic curve for this model was 0.91. Elevated pulmonary dead space fraction is associated with prolonged mechanical ventilation and hospital stay in pediatric patients who undergo surgery for congenital heart disease and has additive predictive value in identifying those at risk for longer duration of mechanical ventilation. Pulmonary dead space may be a useful prognostic tool for clinicians in patients who undergo congenital heart surgery.

Does prophylactic use of dexamethasone have a role in reducing post extubation stridor and reintubation in children?

All children aged from 4 weeks to <5 year, were intubated for at least 48 hours [n=51] during 6 months. Data of the patients treated with DEX (0.5 ml/kg every 6 hours for 3 doses, beginning 6-12 hours prior to extubation) (n=30) were compared with control patients (who had not received medication) (n=21). The DEX and control groups were similar in age i.e., mean ages of DEX group were 16.85+/-14 months, and that of control group were 19.02 +/- 19 months, mean duration of intubation and mechanical ventilation in DEX group was 5.17 +/- 4.58 days, and that in control group was 3.98 +/- 3.60 days. There was no significant difference between DEX and control group in the incidence of postextubation stridor [17% (5/30) vs. 10% (2/21); p = 0.5] and the reintubation rate [7% (2/30) vs. 10% (2/21); p = 0.7]. Our data revealed that the prophylactic use of dexamethasone in planned extubation of high risk children were not effective.

Weaning and extubation readiness in pediatric patients

OBJECTIVE

A systematic review of weaning and extubation for pediatric patients on mechanical ventilation.

DATA SELECTION

Pediatric and adult literature, English language.

STUDY SELECTION

Invited review.

DATA SOURCES

Literature review using National Library of Medicine PubMed from January 1972 until April 2008, earlier cross-referenced article citations, the Cochrane Database of Systematic Reviews, and the Internet.

CONCLUSIONS

Despite the importance of minimizing time on mechanical ventilation, only limited guidance on weaning and extubation is available from the pediatric literature. A significant proportion of patients being evaluated for weaning are actually ready for extubation, suggesting that weaning is often not considered early enough in the course of ventilation. Indications for extubation are even less clear, although a trial of spontaneous breathing would seem a prerequisite. Several indices have been developed in an attempt to predict weaning and extubation success but the available literature would suggest they offer no improvement over clinical judgment. Extubation failure rates range from 2% to 20% and bear little relationship to the duration of mechanical ventilation. Upper airway obstruction is the single most common cause of extubation failure. A reliable method of assessing readiness for weaning and predicting extubation success is not evident from the pediatric literature.

The endotracheal tube air leak test does not predict extubation outcome in critically ill pediatric patients

OBJECTIVE

Endotracheal tube air leak pressures are used to predict postextubation upper airway compromise such as stridor, upper airway obstruction, or risk of reintubation. To determine whether the absence of an endotracheal tube air leak (air leak test >/=30 cm H2O) measured during the course of mechanical ventilation predicts extubation failure in infants and children.

DESIGN

Prospective, blinded cohort.

SETTING

Multidisciplinary pediatric intensive care unit of a university hospital.

PATIENTS

Patients younger than or equal to 18 yrs and intubated >/=24 hrs.

INTERVENTIONS

The pressure required to produce an audible endotracheal tube air leak was measured within 12 hrs of intubation and extubation. Unless prescribed by the medical care team, patients did not receive neuromuscular blocking agents during air leak test measurements.

MEASUREMENTS AND MAIN RESULTS

The need for reintubation (i.e., extubation failure) was recorded during the 24-hr postextubation period. Seventy-four patients were enrolled resulting in 59 observed extubation trials. The extubation failure rate was 15.3% (9 of 59). Seven patients were treated for postextubation stridor. Extubation failure was associated with a longer median length of ventilation, 177 vs. 78 hrs, p = 0.03. Extubation success was associated with the use of postextubation noninvasive ventilation (p = 0.04). The air leak was absent for the duration of mechanical ventilation (i.e., >/=30 cm H2O at intubation and extubation) in ten patients. Absence of the air leak did not predict extubation failure (negative predictive value 27%, 95% confidence interval 6-60). The air leak test was >/=30 cm H2O before extubation in 47% (28 of 59) of patients yet 23 patients extubated successfully (negative predictive value 18%).

CONCLUSIONS

An endotracheal tube air leak pressure >/=30 cm H2O measured in the nonparalyzed patient before extubation or for the duration of mechanical ventilation was common and did not predict an increased risk for extubation failure. Pediatric patients who are clinically identified as candidates for an extubation trial but do not have an endotracheal tube air leak may successfully tolerate removal of the endotracheal tube.

Arterial Switch Operation: Troponin T Does Not Predict Ventilation Requirements

The aim of this study was to assess whether postoperative cardiac troponin T levels could predict ventilation requirements in infants undergoing the arterial switch operation. Cardiac troponin T was measured 6 hours after aortic cross clamping and prior to tracheal extubation in 20 consecutive patients; 10 had simple and 10 had complex (with ventricular septal defect) transposition of the great arteries. The mean plasma troponin T level prior to extubation did not differ significantly in patients who were re-intubated and those who were successfully extubated. The initial cardiac troponin T levels in the complex defect group was significantly higher than in the simple transposition group. There was no correlation between initial cardiac troponin T levels and the duration of mechanical ventilation. There was no difference in mean duration of ventilation between the 2 groups. It was concluded that the postoperative cardiac troponin T level is not a predictor of successful extubation or prolonged artificial ventilation in this subset.

Medical errors affecting the pediatric intensive care patient: incidence, identification, and practical solutions

The complexity of patient care and the potential for medical error make the pediatric ICU environment a key target for improvement of outcomes in hospitalized children. This article describes several event-specific errors as well as proven and potential solutions. Analysis of pediatric intensive care staffing, education, and administration systems, although a less "traditional" manner of thinking about medical error, may reveal further opportunities for improved pediatric ICU outcome.

Medida da freqüência respiratória e do volume corrente para prever a falha na extubação de recém-nascidos de muito baixo peso em ventilação mecânica

OBJETIVO: Verificar se a freqüência respiratória (FR), o volume corrente (VC) e a relação FR/VC poderiam prever a falha na extubação em recém-nascidos de muito baixo peso submetidos à ventilação mecânica. MÉTODOS: Estudo prospectivo, observacional, de recém-nascidos com idade gestacional <37 semanas, peso ao nascer <1.500g, ventilados desde o nascimento por 48 horas a 30 dias. Após a indicação da retirada da ventilação mecânica, o neonato foi colocado em pressão positiva contínua (CPAP) por via traqueal por dez minutos, avaliando-se FR, VC e relação FR/VC por meio de um pneumotacógrafo conectado entre a cânula traqueal e o circuito do ventilador. Em seguida, o recém-nascido foi extubado e colocado em CPAP nasal, considerando-se falha na extubação a necessidade de reintubação em 48 horas. RESULTADOS: Das 35 crianças estudadas, 20 (57%) foram extubadas com sucesso e 15 (43%) necessitaram de reintubação. A FR e a relação FR/VC tenderam a ser maiores no grupo que falhou na extubação; o VC foi similar nos dois grupos. A sensibilidade e a especificidade para falha na extubação foram, respectivamente, 50 e 67% para FR, 40 e 67% para o VC e 40 e 73% para a relação FR/VC. CONCLUSÕES: A FR, o VC e a relação FR/VC apresentaram baixa sensibilidade e especificidade para prever a falha na extubação em recém-nascidos de muito baixo peso.

Extubation after cardiothoracic surgery in neonates, children, and young adults: One year of institutional experience

OBJECTIVE:: Describe risk factors associated with successful and early extubation in the pediatric cardiac intensive care unit. DESIGN:: Retrospective chart review. SETTING:: University hospital, cardiac intensive care unit. MEASUREMENTS AND MAIN RESULTS:: Review of 212 consecutive surgical admissions from January 2003 to January 2004, excluding deaths. Preoperative, intraoperative, and postoperative variables were studied. Successful extubation was defined as no reintubation at any time during the cardiac intensive care unit course and early extubation was defined as mechanical ventilation </=24 hrs. Median subject age was 8 months (range, 1 day-25 yrs), with 57% <1 yr of age and 22% neonates. Fifty-eight (27%) were extubated in the operating room and 122 (58%) were extubated at <24 hrs (mean, 6.1 +/- 7.7 hrs). Only seven patients failed extubation: three in the operating room because of upper airway obstruction and four in the cardiac intensive care unit for acute respiratory failure associated with atelectasis (n = 2), ventricular dysfunction (n = 1), and arrhythmia (n = 1). There were no extubation failures in patients extubated >24 hrs after surgery. A history of prematurity (odds ratio [OR], 5.84, 2.29-14.9; p < .001), base excess (OR, 1.47, 1.27-1.70; p < .001), cardiopulmonary bypass time (OR, 1.01, 1.01 to -1.2; p < .05), and the need for surgical reintervention (OR, 18.29, 2.78 to -120.07; p < .05) were associated with intubation for >24 hrs. CONCLUSION:: Extubation without the need for reintubation can be achieved in nearly all children following cardiothoracic surgery. The majority of successful extubations can be achieved within 24 hrs of surgery.

Insights in pediatric ventilation: timing of intubation, ventilatory strategies, and weaning

PURPOSE OF REVIEW

Mechanical ventilation is a common intervention provided by pediatric intensivists. This fact notwithstanding, the management of mechanical ventilation in pediatrics is largely guided by a few pediatric trials along with careful interpretation and application of adult data.

RECENT FINDINGS

A low tidal volume, pressure limited approach to mechanical ventilation as established by the Acute Respiratory Distress Syndrome Network investigators, has become the prevailing practice in pediatric intensive care. Studies by these investigators suggest that high positive end expiratory pressure and recruitment maneuvers are not uniformly beneficial. High frequency oscillatory ventilation continues to be evaluated in an attempt to provide 'open lung' ventilation. Airway pressure release ventilation is a newer mode of ventilation that may combine the 'open lung' approach with spontaneous breathing. Prone positioning was demonstrated in a recent pediatric trial to have no effect on outcome, while calfactant was found to potentially improve outcomes in pediatric acute respiratory distress syndrome. Ventilator weaning protocols may not be as useful in pediatrics as in adults. Systemic corticosteroids decrease the incidence of post extubation stridor and may reduce reintubation rates.

SUMMARY

Mechanical ventilation with pressure limitation and low tidal volumes has become customary in pediatric intensive care units, and this lung protective approach will continue into the foreseeable future. Further investigation is warranted regarding use of high frequency oscillatory ventilation, airway pressure release ventilation, and surfactant to assist pediatric intensivists in application of these therapies.