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Introduction: Risk-stratification of patients requiring endotracheal intubation and mechanical ventilation in the Emergency Department (ED) is necessary for informed discussions with patients regarding goals-of-care. Frailty is a clinical state characterized by reduced physiologic reserve, and resulting from accumulation of physiological stresses and comorbid disease. Frailty is increasingly being identified as an important independent predictor of outcome among critically ill patients. Our objective was to identify the impact of clinical frailty (defined by the Clinical Frailty Scale [CFS]) on in-hospital mortality and resource utilization of ED patients requiring endotracheal intubation and mechanical ventilation. Methods: We analyzed a prospectively collected registry (2011-2016) of patients requiring endotracheal intubation in the ED at two academic hospitals and six community hospitals. We included all patients ≥18 years of age, who survived to the point of ICU admission. All patient information, outcomes, and resource utilization were stored in the registry. CFS scores were obtained through chart abstraction by two blinded reviewers. The primary outcome, in-hospital mortality, was analyzed using a multivariable logistic regression model, controlling for confounding variables (including patient sex, comorbidities, and illness severity). We defined “frailty” as a CFS ≥ 5. Results: 4,622 patients were included. Mean age was 61.2 years (SD: 17.5), and 2,614 (56.6%) were male. Frailty was associated with increased risk of in-hospital mortality, as compared to those who were not frail (adjusted odds ratio [OR] 2.21 [1.98-2.51]). Frailty was also associated with higher likelihood of discharge to long-term care (adjusted OR 1.78 [1.56-2.01]) among patients initially from a home setting. Frail patients were more likely to fail extubation during their hospitalization (adjusted OR 1.81 [1.67-1.95]) and were more likely to require tracheostomy (adjusted OR 1.41 [1.34-1.49]). Conclusion: Presence of frailty among ED patients requiring endotracheal intubation and mechanical ventilation was associated with increased in-hospital mortality, discharge to long-term care, extubation failure, and tracheostomy. ED physicians should consider the impact of frailty on patient outcomes, and discuss associated prognosis with patients prior to intubation.
Critically ill patients frequently suffer from gastrointestinal dysfunction as the intestine is a vulnerable organ. In critically ill patients who require nutritional support, the current guidelines recommend the use of enteral nutrition within 24–48 h and advancing towards optimal nutritional goals over the next 48–72 h; however, this may be contraindicated in patients with acute gastrointestinal injury because overuse of the gut in the acute phase of critical illness may have an adverse effect on the prognosis. We propose that trophic feeding after 72 h, as a partial gut rest strategy, should be provided to critically ill patients during the acute phase of illness as an organ-protective strategy, especially for those with acute gastrointestinal injury.
Retrospective data evaluated increases in advanced medical support for children with medically attended acute respiratory illness (MAARI) during influenza outbreak periods (IOP). Advanced support included hospitalisation, intensive care unit admission, or mechanical ventilation, for children aged 0–17 years hospitalised in Maryland's 50 acute-care hospitals over 12 influenza seasons. Weekly numbers of positive influenza tests in the Maryland area defined IOP for each season as the fewest consecutive weeks, including the peak week containing at least 85% of positive tests with a 2-week buffer on either side of the IOP. Peak IOP (PIOP) was defined as four consecutive weeks containing the peak week with the most number of positive influenza tests. Off-PIOP was defined as the ‘shoulder’ weeks during each IOP. Non-influenza season (NIS) was the remaining weeks of that study season. Rate ratios of mean daily MAARI-related admissions resulting in advanced medical support outcomes during PIOP or Off-PIOP were compared with the NIS and were significantly elevated for all 12 study seasons combined. The results suggest that influenza outbreaks are associated with increased advanced medical support utilisation by children with MAARI. We feel that this data may help preparedness for severe influenza epidemics or pandemic.
Fetal growth restriction (FGR) and preterm birth are frequent co-morbidities, both are independent risks for brain injury. However, few studies have examined the mechanisms by which preterm FGR increases the risk of adverse neurological outcomes. We aimed to determine the effects of prematurity and mechanical ventilation (VENT) on the brain of FGR and appropriately grown (AG, control) lambs. We hypothesized that FGR preterm lambs are more vulnerable to ventilation-induced acute brain injury. FGR was surgically induced in fetal sheep (0.7 gestation) by ligation of a single umbilical artery. After 4 weeks, preterm lambs were euthanized at delivery or delivered and ventilated for 2 h before euthanasia. Brains and cerebrospinal fluid (CSF) were collected for analysis of molecular and structural indices of early brain injury. FGRVENT lambs had increased oxidative cell damage and brain injury marker S100B levels compared with all other groups. Mechanical ventilation increased inflammatory marker IL-8 within the brain of FGRVENT and AGVENT lambs. Abnormalities in the neurovascular unit and increased blood–brain barrier permeability were observed in FGRVENT lambs, as well as an altered density of vascular tight junctions markers. FGR and AG preterm lambs have different responses to acute injurious mechanical ventilation, changes which appear to have been developmentally programmed in utero.
We utilized de-identified data to evaluate increases in four outcomes during influenza outbreak periods (IOPs) including: hospitalization, intensive care unit admission, mechanical ventilation or death for adults aged 18 years or older with medically attended acute respiratory illnesses (MAARI) admitted to any of Maryland's 50 acute-care hospitals over 12 years. Weekly numbers of positive influenza tests in the Maryland area were obtained from the US Center for Disease Control and Prevention interactive website. The fewest consecutive weeks around the peak week containing at least 85% of the positive tests defined the IOP. Weekly counts of individual study outcomes were positively correlated with regional weekly counts of positive influenza tests during all the IOPs over 12 years. Also, rate ratios comparing daily occurrences of each study outcome between the IOP and non-IOP were significantly elevated. These results confirm conclusions of previous studies that influenza outbreaks are clearly associated with deaths and increased use of advanced medical resources by patients with MAARI. These data analyses suggest that increased efforts to develop more effective influenza vaccines and therapeutics should be a priority.
Objective: Refractory status epilepticus (RSE) can influence the outcome of status epilepticus (SE). In the present study, we report the aetiology and predictors of outcomes of RSE in a developing country. Methods: This is a prospective hospital-based study of SE patients (continuous seizures for five minutes or more). Those who had SE persisting after two antiepileptic drugs were defined as having RSE. We present the demographic information, duration, and type of SE, and we note its severity using the status epilepticus severity score (STESS), its aetiology, comorbidities and imaging findings. The outcome of RSE was defined as cessation of seizures and the condition upon discharge, as assessed by the modified Rankin Scale. Results: A total of 35 (42.5%) of our 81 patients had RSE. The median duration of SE before starting treatment was 2 hours (range=0.008-160 h). The most common causes of RSE were stroke in 5 (14.3%), central nervous system (CNS) infections in 12 (34.3%) and metabolic encephalopathies in 13 (37.1%) patients. Some 21 (60%) patients had comorbidities, and the STESS was favourable in 7 (20%) patients. A total of 14 (20%) patients died, but death was directly related to SE in only one of these. Some 10 patients had super-refractory status epilepticus, which was due to CNS infection in 5 (50%) and metabolic encephalopathy in 3 (30%). On multivariate analysis, an unfavourable STESS (p=0.05) and duration of SE before treatment (p=0.01) predicted RSE. Metabolic aetiology (p=0.05), mechanical ventilation (p<0.001) and age >60 years (p=0.003) were predictors of poor outcomes. Conclusions: RSE was common (42.5%) among patients with SE in a tertiary care center in India. It was associated with high mortality and poor outcomes. Age above 60 years and metabolic aetiology were found to be predictors of poor outcomes.
The use of ultrasound for assessing diaphragmatic dysfunction after paediatric cardiac surgery may be under-utilised. This study aimed to evaluate the role of bedside ultrasound performed by an intensivist to diagnose diaphragmatic dysfunction and the need for plication after paediatric cardiac surgery.
We carried out a retrospective cohort study on prospectively collected data of postoperative children admitted to the paediatric cardiac ICU during 2013. Diaphragmatic dysfunction was suspected based on difficulties in weaning from positive pressure ventilation or chest X-ray findings. Ultrasound studies were performed by the paediatric cardiac ICU intensivist and confirmed by a qualified radiologist.
Out of 344 postoperative patients, 32 needed diaphragm ultrasound for suspected dysfunction. Ultrasound studies confirmed diaphragmatic dysfunction in 17/32 (53%) patients with an average age and weight of 10.8±3.8 months and 6±1 kg, respectively. The incidence rate of diaphragmatic dysfunction was 4.9% in relation to the whole population. Diaphragmatic plication was needed in 9/17 cases (53%), with a rate of 2.6% in postoperative cardiac children. The mean plication time was 15.1±1.3 days after surgery. All patients who underwent plication were under 4 months of age. After plication, they were discharged with mean paediatric cardiac ICU and hospital stay of 19±3.5 and 42±8 days, respectively.
Critical-care ultrasound assessment of diaphragmatic movement is a useful and practical bedside tool that can be performed by a trained paediatric cardiac ICU intensivist. It may help in the early detection and management of diaphragmatic dysfunction after paediatric cardiac surgery through a decision-making algorithm that may have potential positive effects on morbidity and outcome.
Prehospital endotracheal intubation (ETI) following traumatic brain injury in urban settings is controversial. Studies investigating admission arterial blood gas (ABG) patterns in these instances are scant.
Outcomes in patients subjected to divergent prehospital airway management options following severe head injury were studied.
This was a retrospective propensity-matched study in patients with isolated TBI (head Abbreviated Injury Scale (AIS) ≥ 3) and Glasgow Coma Scale (GCS) score of ≤ 8 admitted to a Level 1 urban trauma center from January 1, 2003 through October 31, 2011. Cases that had prehospital ETI were compared to controls subjected to oxygen by mask in a one to three ratio for demographics, mechanism of injury, tachycardia/hypotension, Injury Severity Score, type of intracranial lesion, and all major surgical interventions. Primary outcome was mortality and secondary outcomes included admission gas profile, in-hospital morbidity, ICU length of stay (ICU LOS) and hospital length of stay (HLOS).
Cases (n = 55) and controls (n = 165) had statistically similar prehospital and in-hospital variables after propensity matching. Mortality was significantly higher for the ETI group (69.1% vs 55.2% respectively, P = .011). There was no difference in pH, base deficit, and pCO2 on admission blood gases; however the ETI group had significantly lower pO2 (187 (SD = 14) vs 213 (SD = 13), P = .034). There was a significantly increased incidence of septic shock in the ETI group. Patients subjected to prehospital ETI had a longer HLOS and ICU LOS.
In isolated severe traumatic brain injury, prehospital endotracheal intubation was associated with significantly higher adjusted mortality rate and worsened admission oxygenation. Further prospective validation of these findings is warranted.
KaramanosE, TalvingP, SkiadaD, OsbyM, InabaK, LamL, AlbuzO, DemetriadesD. Is Prehospital Endotracheal Intubation Associated with Improved Outcomes In Isolated Severe Head Injury? A Matched Cohort Analysis. Prehosp Disaster Med. 2013;28(6):1-5.
Given the great number of chronic care patients facing the end of life and the challenges of critical care delivery, there has been emerging evidence supporting the benefit of palliative care in the intensive care unit (ICU). We studied the relationship between the timing of a palliative care consult (PCC) and two utilization outcomes — length of stay (LOS) and pharmacy costs — in ventilator-assisted ICU patients.
A retrospective chart review was conducted (N = 90). Summed pharmacy costs were compared using a paired t test before and after PCC. Spearman correlations were performed between days to PCC and ICU LOS, ventilator days, and days to death following ventilator discontinuation.
Number of days from admission to PCC was correlated with total days on ventilator (ρ = 0.685, p < 0.0001) and total ICU LOS (ρ = 0.654, p < 0.0001). Number of days to PCC was correlated with pre-PCC total medication costs (ρ = 0.539, p < 0.0001). Median medication costs were significantly reduced after the PCC (p < 0.0001), from $230.96 to 30.62. Median medication costs decreased for all categories except for analgesics, antiemetics, and opioids. The number of patients receiving opioid infusion increased (37 vs. 90%) after PCC (p < 0.0001).
Significance of results:
Earlier timing for PCC in the ICU is associated with a lower LOS through quicker mechanical ventilation (MV) withdrawal, presenting a unique opportunity to both decrease costs and improve patient care.
This chapter discusses the management of mechanical ventilation. The different modes of ventilation are controlled mandatory ventilation (CMV), assist volume control, synchronized intermittent mandatory ventilation (SIMV), pressure control (PC), and pressure support (PS). The two ventilation strategies that can be used in critically ill patients in the emergency department are lung protective strategy and obstructive strategy. Both of these strategies utilize the assist control (AC) volume cycled mode of ventilation. The lung protective strategy is designed for patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS), or who are at risk for lung injury. Obstructive strategy is designed for patients with obstructive lung disease (i.e., asthma or COPD) whose airways are constricted and therefore require a longer time to fully exhale. There are two basic pressures that should be monitored in mechanically ventilated patients: peak inspiratory pressure and plateau pressure.
This chapter deals with issues related to mechanical ventilation in general and considers those relevant to the obstetric patient in particular. The most common modes of mechanical ventilation are: volume-controlled continuous mandatory ventilation (VC-CMV), pressure-controlled continuous mandatory ventilation (PC-CMV), intermittent mandatory ventilation (IMV), continuous mandatory ventilation (CMV), airway pressure release ventilation (APRV) and positive end-expiratory pressure (PEEP). All patients receiving mechanical ventilation should be monitored by pulse oximetry. Non-invasive ventilation can be delivered nasally or by face mask, using either a conventional mechanical ventilator or a machine designed specifically for this purpose. The 2009 H1N1 influenza pandemic and the particular susceptibility of pregnancy in such circumstances reinforce the need to appraise the rationale for mechanical ventilation in such patients. Finally, APRV as a ventilatory paradigm, in particular, may be particularly useful in the pregnant patient with pneumonits, acute lung injury, or acute respiratory distress syndrome (ARDS).
Various physiological changes occur as a result of the pregnant state, affecting patients with pre-existing lung disease and affecting the assessment and management of the patient with respiratory failure. Asthma, pulmonary infections, tuberculosis are some of the conditions not specific to pregnancy. Acute severe asthma in pregnancy may be treated as in the non-pregnant patient with intravenous beta- 2-adrenergic agonists, intravenous theophylline, intravenous magnesium sulfate and steroids. Standard drug therapy, namely with isoniazid, rifampin, and ethambutol has an acceptable safety profile in pregnancy and is recommended for pregnant women by the US Centers for Disease Control and Prevention and the American Thoracic Society. Acute respiratory distress syndrome (ARDS) occurs fairly frequently in pregnancy and is a leading cause of maternal death. Several approaches to respiratory support, including conventional mechanical ventilation, airway pressure release ventilation, high-frequency oscillation, and extracorporeal membrane oxygenation, have been used successfully in pregnancy.
The objective of the study was to identify incidence, aetiology, and outcomes of extubation failure in infants with shunt-dependent pulmonary blood flow at a single tertiary care, academic children's hospital. The second objective of this study was to determine the haemodynamic effects of transition of positive pressure ventilation to spontaneous breathing in infants with extubation failure.
Patients and methods
Extubation failure for our study was defined as the need for positive pressure ventilation within 96 hours after extubation. We collected demographics, pre-operative, intra-operative, post-operative, and peri-extubation data in a retrospective, observational format in patients who underwent a modified Blalock–Taussig shunt between January, 2005 and March, 2011. Infants undergoing Norwood operation or Damus–Kaye–Stansel with modified Blalock–Taussig shunt were excluded from the study. The cardiorespiratory variables collected before extubation and immediately after extubation included heart rate, respiratory rate, mean arterial blood pressure, central venous pressures, near infrared spectroscopy, oxygen saturations, and lactate levels. Clinical outcomes evaluated included the success or failure of extubation, cardiovascular intensive care unit length of stay, hospital length of stay, and mortality. Descriptive and univariate statistics were utilised to compare groups with extubation failure and extubation success.
Of the 55 eligible patients during the study period, extubation failure occurred in 27% (15/55) of the patients. Of the 15 patients with extubation failure, 10 patients needed reintubation and five patients received continuous positive pressure ventilation without getting reintubated. There were three patients who had extubation failure in the first 2 hours after extubation, nine patients in the 2–24-hour period, and three patients in the 24–96-hour period. In all, eight patients were extubated in the second attempt after the first extubation failure, with a median duration of mechanical ventilation of 2 days (1 day, 6 days). The median age of patients at extubation was 19 days (12 days, 22 days) and median weight of patients was 3.6 kg (3.02 kg, 4.26 kg). In all, 38% (21/55) of the patients were intubated before surgery. The most common risk factors for failed extubation were lung disease in 46% (7/15), cardiac dysfunction in 26% (4/15), diaphragmatic paralysis in 13% (2/15), airway oedema in 6% (1/15), and vocal cord paralysis in 6% (1/15). The median duration of mechanical ventilation was 4 days (1 day, 10.5 days), median cardiovascular intensive care unit length of stay was 11 days (6.5 days, 23.5 days), and the median hospital length of stay was 30 days (14 days, 48 days). The overall mortality at the time of hospital discharge was 7%.
Extubation failure in infants with shunt-dependent pulmonary blood flow and univentricular physiology is high and aetiology is diverse. Cardiopulmonary effects of removal of positive pressure ventilation are more pronounced in children with extubation failure and include escalation in the need for oxygen requirement and increase in mean arterial blood pressure. The majority of extubation failures in this select patient population occurs in the first 24 hours. Extubation failure in these patients is not associated with increased hospital length of stay or mortality.
Continuous monitoring of end-tidal carbon dioxide (PETCO2) is a long-established standard of care in the operating room (OR). Carbon dioxide can be useful to monitor the mechanically ventilated patient when used in conjunction with other monitors of the patient's clinical status. CO2 monitoring is affected by changes in metabolism or CO2 production, cardiovascular function, and respiratory function. Comparison of the gradient between arterial and end-tidal CO2 (PaCO2-PetCO2) can offer valuable information regarding a patient's clinical status. In newborns, the therapeutic administration of CO2 in the ventilator circuit has been used in the preoperative management of hypoplastic left heart syndrome. Volumetric capnography or volumetric CO2 (VCO2) is the measurement of CO2 as a function of volume as opposed to time. When CO2 production increases with constant minute ventilation, PaCO2 will increase. Alveolar minute ventilation can be used as a guide for predicting the PaCO2 that may result from adjusting ventilation parameters.
This chapter examines different time- and volume-based capnograms, and analyzes them from a clinical perspective, with a special focus on problems related to ventilation, by far the most common clinical application of capnography. A water trap with a large internal volume can introduce artifacts when high airway pressures during inspiration compress gas in the trap. The capnogram provides evidence of acutely reduced pulmonary perfusion coincident with a drop in cardiac output. The most important use of capnography in the field, in the intensive care unit, and in the operating room comes with the establishment of an artificial airway. An individual tracing of the time-based capnogram left a number of questions unanswered, which the single breath volume-based capnogram provides. The data offered by the volume-based capnogram refine the information offered by time-based capnography.
Anesthesiologists monitor their patients' breathing by listening to the lungs or auscultating over the trachea, counting the respiratory rate, watching chest movement and tidal volume, and employing pulse oximetry and capnography. This chapter focuses on issues related to capnography specific to anesthesia and the operating room. Capnography is the best monitor to identify complete disconnection of the breathing circuit. Exhaled tidal volume is a sensitive indicator of leaks and partial disconnects during mechanical ventilation. Capnography will continue to detect expired CO2 as long as the patient's exhaled tidal volume passes sidestream or mainstream sampling ports. Patients with chronic obstructive pulmonary disease or asthma exhibit typical capnograms with upsloping expired values brought about by the slow emptying of partially obstructed segments of the lungs. Intermittent PaCO2 determination has been used as a routine parameter for acid-base management during cardiopulmonary bypass (CPB).
Capnography and capnometry provide useful information that may help improve decision-making and reduce complications during transport. This chapter reviews specific clinical applications of capnography and capnometry: assuring proper endotracheal tube placement, monitoring airway circuit integrity, monitoring the consistency of mechanical ventilation, improving safety in procedural sedation, assessing cardiac output, and evaluating patients in cardiac arrest. Capnometry and capnography aid in the confirmation of correct endotracheal tube placement. End-tidal CO2 (ETCO2) measurement can accurately detect esophageal intubation because CO2 is exhaled through the trachea, and not the esophagus. Once an airway device is in place, continuous monitoring is important to assure ventilator circuit patency, including that of the endotracheal tube, and to assure consistent levels of ventilation. Capnography is the gold standard for monitoring patients on airway appliances and ventilator circuits, and there are useful roles for the technology during procedural sedation and evaluating patients in the time surrounding arrest states.
Monitoring PETCO2 serves as a useful adjunct in weaning postoperative patients from mechanical ventilation. Several laboratory techniques are commonly used as adjuncts to clinical assessment of the adequacy of ventilation. This chapter focuses on the procedures that are utilized for weaning patients from the ventilator. Successful weaning during the postoperative period requires the assurance that the patient is clinically stable and without clinically significant residual effects of the anesthetic agents utilized during surgery. Some clinicians utilize PETCO2 as a marker of the metabolic rate and, therefore, as a way of determining optimal ventilator settings during the weaning process. A variety of different devices are available to the practitioner caring for these patients. Data from PETCO2 monitoring should be used in conjunction with information derived from a clinical evaluation of the patient.
This chapter highlights the role of capnography as a monitoring tool with the different adjuncts to mechanical ventilation that are currently used in critically ill patients. The application of positive end-expiratory pressure (PEEP) is used to increase lung volume and improve oxygenation in patients with acute lung injury (ALI). Studies of unilateral lung injury demonstrate that the consolidated lung regions do not expand to total lung capacity during inflation. Tracheal gas insufflation (TGI) is an adjunct to mechanical ventilation that allows ventilation with small tidal volumes while CO2 is satisfactorily eliminated. High-frequency ventilation (HFV) techniques have three essential elements in common: a high-pressure flow generator, a valve for flow interruption, and a circuit for connection to the patient. Measurement of deadspace fraction early in the course of acute respiratory failure may provide clinicians important physiologic and prognostic information.
It is important to keep in mind the differences between PETCO2, alveolar CO2, and arterial PCO2 (PaCO2) as extremes of temperature and altitude, and the potential for sensor interference by condensation or various body fluids, may significantly affect the performance of these devices. This chapter presents the evidence for use of PETCO2 monitoring to guide ventilation in the field and reviews each type of device available, discussing the advantages and disadvantages of each. In theory, monitoring of PETCO2 data should lead to a low incidence of hyperventilation, regardless of whether manual or mechanical ventilation is used. Quantitative capnometry has great potential for guiding ventilation in the prehospital arena. Advances in the technology for PETCO2 monitoring, including capnometry and capnography, have allowed these devices to be small and durable enough to be carried into the field, where they can help avoid hyperventilation and injurious ventilation patterns.