Protracted Mechanical Ventilation Research Articles

Acquired Tracheomegaly in Critically Ill Patients With COVID-19: A Literature Review

Tracheomegaly is defined as an abnormally dilated trachea and is seen in patients requiring long-standing mechanical ventilation and/or significant hyperinflation of their endotracheal or tracheostomy tube cuffs can occur in adults with severe COVID-19. Tracheomegaly is linked with inadequate nutrition, pneumonia, diabetes, hypotension, steroids, and protracted mechanical ventilation, which are common in COVID-19 patients. Findings include cuff leaks that necessitate cuff overinflation to maintain adequate tidal volumes. Tracheomegaly can be diagnosed with chest radiographs, chest computed tomography, bronchoscopy, or diagnostic laryngoscopy or tracheoscopy. This condition leads to a concern for obstruction, airway collapse, aspiration pneumonia, and iatrogenic tracheal injuries.

A four-probiotic preparation for ventilator-associated pneumonia in multi-trauma patients: results of a randomized clinical trial

The role of probiotics in the prevention of ventilator-associated pneumonia (VAP) remains inconclusive. The aim of this study was to assess the efficacy of a probiotic regimen for VAP prophylaxis in mechanically ventilated multi-trauma patients, intubated immediately after the injurious insult. In a randomized, placebo-controlled study enrolling multi-trauma patients, patients expected to require mechanical ventilation for >10 days were assigned at random to receive prophylaxis with a probiotic formula (n=59) or placebo (n=53). The probiotic formula was a preparation of Lactobacillus acidophilus LA-5 [1.75×109 colony-forming units (cfu)], Lactobacillus plantarum (0.5×109 cfu), Bifidobacterium lactis BB-12 (1.75×109 cfu) and Saccharomyces boulardii (1.5×109 cfu) in sachets. Each patient received two sachets twice daily for 15 days: one through the nasogastric tube and one spread on the oropharynx. The incidence of VAP was the primary endpoint. The incidence of other infections and sepsis, and the duration of hospital stay were the secondary endpoints. Administration of probiotics reduced the incidence of VAP [11.9% vs 28.3%, hazard ratio (HR) 0.34, 95% confidence interval (CI) 0.13-0.92; P=0.034] and sepsis [6.8% vs 24.5%, odds ratio 0.22, 95% CI 0.07-0.74: P=0.016]. Furthermore, probiotic prophylaxis reduced the time of stay in the intensive care unit (ICU) and the length of hospital stay. The prophylactic use of probiotics with a combination of enteral and topical application to the oropharynx had a positive effect on the incidence of VAP and sepsis, as well as on ICU and total hospital stay in patients receiving protracted mechanical ventilation.

Admission of tetanus patients to the ICU: a retrospective multicentre study

BackgroundAn extended course of tetanus (up to 6 weeks) requiring ICU admission and protracted mechanical ventilation (MV) may have a significant impact on short- and long-term survival. The subject is noteworthy and deserves to be discussed.MethodsTwenty-two ICUs in France performed tetanus screenings on patients admitted between January 2000 and December 2014. Retrospective data were collected from hospital databases and through the registers of the town hall of the patients.ResultsSeventy patients were included in 15 different ICUs. Sixty-three patients suffered from severe or very severe tetanus according to the Ablett classification. The median age was 80 years [interquartile range 73–84], and 86% of patients were women. Ninety per cent of patients (n = 63) required MV for a median of 36 days [26–46], and 66% required administration of a neuromuscular-blocking agent for 23 days [14–29]. A nosocomial infection occurred in 43 patients (61%). ICU and 1-year mortality rates were 14% (n = 10) and 16% (n = 11), respectively. Forty-five per cent of deaths occurred during the first week. Advanced age, a higher SAPS II, any infection, and the use of vasopressors were significantly associated with a lower number of days alive without ventilator support by day 90. Age was the only factor that significantly differed between deceased and survivors at 1 year (83 [81–85] vs. 79 [73–84] years, respectively; p = 0.03). Sixty-one per cent of survivors suffered no impairment to their functional status.ConclusionIn a high-income country, tetanus mainly occurs in healthy elderly women. Despite prolonged MV and extended ICU length of stay, we observed a low 1-year mortality rate and good long-term functional status.

Antecedent Predictors of Feeding Outcomes in Premature Infants With Protracted Mechanical Ventilation

The aim of the present study was to define risk factors associated with gastrostomy in premature infants receiving protracted mechanical ventilation (≥30 days). Retrospective data collected on 170 preterm neonates (birth weight <1500 g) who received uninterrupted mechanical ventilation for ≥30 days were analyzed with logistic regression methods to predict the association of gastrostomy with cardiorespiratory, infectious, and neurological morbidities. A total of 32 of 170 infants had gastrostomy tubes. Including all of the covariates in 1 model, duration of cumulative ventilation (P < 0.001) and uninterrupted ventilation (P < 0.001), and ventriculoperitoneal shunt (P = 0.02) were significant predictors, whereas sepsis, intraventrical hemorrhage grade III or IV, and patent ductus arteriosus ligation were not. Respiratory severity score (mean airway pressure × fraction of inspired oxygen) calculated at 30 days of life was also a significant predictor (P = 0.01). In infants with protracted mechanical ventilation, the degree of respiratory support at 1 month of age, prolonged respiratory morbidity, and neuropathology are the significant predictors for gastrostomy.

Automated weaning and spontaneous breathing trial systems versus non-automated weaning strategies for discontinuation time in invasively ventilated postoperative adults.

Automated systems use closed-loop control to enable ventilators to perform basic and advanced functions while supporting respiration. Selected automated systems can now not only measure selected respiratory variables and adapt ventilator output to individual patient needs by operationalizing predetermined algorithms but also automate the conduct of spontaneous breathing trials (SBTs). To summarize the evidence comparing automated weaning and SBT systems to non-automated mechanical ventilation strategies on time to mechanical ventilation discontinuation in adult postoperative patients. In secondary objectives we ascertained differences between automated weaning and SBT systems and non-automated mechanical ventilation discontinuation strategies on clinical outcomes (time to successful extubation, time to first SBT and first successful SBT, mortality, total duration of ventilation, intensive care unit (ICU) and hospital lengths of stay, use of non-invasive ventilation (NIV) following extubation, and adverse events). We searched CENTRAL (The Cochrane Library 2013, Issue 5); MEDLINE (OvidSP) (1966 to May 2013); EMBASE (OvidSP) (1988 to May 2013); CINAHL (EBSCOhost) (1982 to May 2013), Evidence Based Medicine Reviews and Ovid Health Star (1999 to May 2013), conference proceedings, trial registration websites, and contacted authors and content experts to identify potentially eligible trials. Randomized and quasi-randomized trials comparing automated weaning and SBT systems to non-automated mechanical ventilation discontinuation strategies in intubated adults in the postoperative setting. Two review authors independently assessed trial quality and abstracted data according to prespecified criteria. Sensitivity and subgroup analyses were planned to assess the impact of the type of (i) clinician primarily involved in implementing the automated weaning and SBT systems, (ii) intensive care unit (ICU), and (iii) non-automated discontinuation (control) strategy utilized on selected outcomes. We identified one randomized controlled trial of high quality, involving 300 patients , comparing SmartCare™ to a written protocol. In this trial, SmartCare™ had no effect on discontinuation time. While SmartCare™ significantly reduced the time to the first SBT (mean difference (MD) -0.34 days, 95% CI -0.60 to -0.08; P = 0.01) it did not reduce the time to the first successful SBT (MD -0.25 days, 95% CI -0.55 to 0.05; P = 0.10) and other clinically important outcomes. SmartCare™ did not demonstrate beneficial effects on most clinically important outcomes including time to successful extubation, total duration of mechanical ventilation, ICU and hospital lengths of stay, and the requirement for tracheostomy. Moreover, SmartCare™ did not favourably impact reintubation, mortality, self-extubation, and the proportion of patients undergoing protracted mechanical ventilation, with a small numbers of events in this single trial. There is a paucity of evidence from randomized controlled trials to support or refute use of automated weaning and SBT systems in discontinuing invasive mechanical ventilation in adult postoperative patients. In a single large trial of high methodologic quality, while the use of SmartCare™ to adjust ventilator settings and conduct SBTs shortened the time to undergoing the first SBT, it did not reduce the time to the first successful SBT or the rate of tracheostomy compared to a written protocol implemented by physicians. SmartCare™ did not demonstrate beneficial effects on clinically important outcomes including time to mechanical ventilation discontinuation, time to successful discontinuation, total duration of mechanical ventilation, and ICU and hospital lengths of stay. Additional well-designed, adequately powered randomized controlled trials are needed to clarify the role for SmartCare™ on important outcomes in patients who predominantly require short term ventilation and in specific postoperative patient populations.

Clinical Patterns in Extremely Preterm (22 to 24 Weeks of Gestation) Infants in Relation to Survival Time and Prognosis

We investigated time-related predictors of death or neurological sequelae in extremely preterm infants (EPI) born at 22 to 24 weeks' gestation by categorizing clinical patterns according to their survival time and morbidity. Data on 113 infants born at 22 to 24 weeks' gestation from January 1991 through April 2006 were analyzed by a case-control approach. Cesarean section, Apgar score <or= 3 at 5 minutes, and pulmonary hypoplasia were significantly associated with death at < 24 hours of life. Among infants who survived >or= 24 hours, pulmonary hemorrhage and intraventricular hemorrhage (IVH) were significantly associated with death by day 6. Among those surviving >or= 7 days, sepsis and severe IVH were significantly associated with death. Assessment of survivors at a minimum follow-up period of 2 years revealed that protracted mechanical ventilation was significantly associated with a poor neurological outcome. There are various characteristic key events in relation to the outcome at different ages of life in EPI born at 22 to 24 weeks' gestation. Clinicians and parents should discuss management options for the infant on the basis of these findings.

Neuromuscular dysfunction acquired in critical illness: a systematic review

To determine the prevalence, risk factors, and outcomes of critical illness neuromuscular abnormalities (CINMA). Systematic review. MEDLINE, EMBASE, CINAHL, and the Cochrane Library were searched for reports on adult ICU patients who were evaluated for CINMA clinically and electrophysiologically. Studies were included if they contained sufficient data to quantify the association between CINMA and relevant exposures and/or outcome variables. CINMA was diagnosed in 655 of 1421 [46% (95% confidence interval 43-49%)] adult ICU patients enrolled in 24 studies, all with inclusion criteria of sepsis, multi-organ failure, or prolonged mechanical ventilation. Diagnostic criteria for CINMA were not uniform, and few reports unequivocally differentiated between polyneuropathy, myopathy, and mixed types of CINMA. The risk of CINMA was associated with hyperglycemia (and inversely associated with tight glycemic control), the systemic inflammatory response syndrome, sepsis, multiple organ dysfunction, renal replacement therapy, and catecholamine administration. Across studies, there was no consistent relationship between CINMA and patient age, gender, severity of illness, or use of glucocorticoids, neuromuscular blockers, aminoglycosides, or midazolam. Unadjusted mortality was not increased in the majority of patients with CINMA, but mechanical ventilation and ICU and hospital stay were prolonged. The risk of CINMA is nearly 50% in ICU patients with sepsis, multi-organ failure, or protracted mechanical ventilation. The association of CINMA with frequently cited CINMA risk factors (glucocorticoids, neuromuscular blockers) and with short-term survival is uncertain. Available data indicate glycemic control as a potential strategy to decrease CINMA risk.

Neonatal Respiratory Distress Syndrome After Repeat Exposure to Antenatal Corticosteroids: A Randomized Controlled Trial

The risk of neonatal lung disease such as respiratory distress syndrome (RDS) is increased in preterm births. Considerable morbidity may be expected both immediately and in the longer term. The best management has been a course of maternal steroid therapy, but this has not proved effective for infants born more than 1 week after initial treatment. Repeat doses of prenatal steroids have not been endorsed outside of clinical trials. There is some concern that prenatal steroids may increase the risk of maternal infection after preterm prelabor membrane rupture. The investigators conducted a hospital-based trial in 982 women, seen at 23 hospitals in Australia and New Zealand, who remained at risk of preterm birth at less than 32 weeks gestation 1 week or longer after an initial course of steroids. They were randomly assigned to receive either a repeat intramuscular dose of Celestone Chronodose (7.8 mg betamethasone sodium phosphate and 6 mg of betamethasone acetate) or a saline placebo injection. Fewer infants exposed to multiple steroid treatments had RDS. The NNTB (number needed to treat to benefit) was 14 with a 95% confidence interval (CI) of 8 to 50. Multiply exposed infants had less severe lung disease in general (NNTB, 14; 95% CI, 9–29). These infants required less oxygen therapy and less protracted mechanical ventilation than did placebo recipients. Birth weight, length, and head circumference did not differ between in the treatment and control groups. Z scores of weight-adjusted mean difference and head circumference—but not length—were lower at birth when infants were repeatedly exposed to steroids, but no such differences were evident at the time of hospital discharge. Major causes of infant deaths in the hospital were comparable in the 2 groups. Average gestational ages at birth also were similar. Apgar scores, rates of admission to neonatal intensive care, and rates of intracerebral disorders, retinopathy of prematurity, necrotizing enterocolitis, and all neonatal infections were similar in the 2 management groups. Similar numbers of women required treatment for clinical chorioamnionitis. More women given repeat steroid therapy had operative delivery. The investigators conclude that a repeat course of antenatal maternal steroid therapy clearly is beneficial for women who are still at risk of preterm birth 1 week or longer after an initial course.

Favorable short- and long-term outcomes of prolonged translaryngeal intubation in critically ill children.

In those children who require protracted mechanical ventilation, we use long-term intubation in order to avoid the consequences of tracheostomy in young children. A retrospective 9-year review was performed to document the efficacy and safety of this practice. A retrospective review of children admitted from January 1, 1991, to December 31, 1998, who required mechanical ventilatory support for at least 7 consecutive days was performed. Data are presented as mean +/- standard deviation. There were 98 children, ventilated for a total of 1967 days, who satisfied review criteria. They had an average age of 6.1 +/- 5.3 years (range, 3 months to 17 years) a total body surface area burn of 53 +/- 25% (range, 0-100%), and 71 of 98 (72%) had suffered an inhalation injury. They were ventilated for 19.7 +/- 16.8 days (range, 7-92 days) and were hospitalized for 67.8 +/- 48.9 days (range, 9-211 days). Ninety-three percent (91 of 98) of the patients were maintained on morphine infusions at a mean hourly rate of 0.35 +/- 0.33 mg/kg/hr (range, 0.01-4.38) and 78% (76 of 98) on midazolam infusions at a mean hourly rate of 0.14 +/- 0.17 mg/kg/hr (range, 0.01-1.82). Neuromuscular blocking agents were administered in 39% (38 of 98) of patients during all or part of 355 (18%) of the 1967 ventilator days. Patients were ventilated with an oral endotracheal (ET) tube in 82% of ventilator days and nasal ET tube in 18% of ventilator days. Two patients (2%) required tracheostomies for long-term management, and five patients (5.1%) died during the study period unrelated to airway issues. There were five unplanned extubation events, for an incidence rate of 2.54 per 1000 ventilator days. All patients were reintubated successfully. Thirteen ET tubes needed to be changed for issues such as leaking cuffs. Patients were followed up for a mean of 2.99 +/- 2.24 years (range, 1 month to 8 years). Possible sequelae related to prolonged intubation were noted in follow-up visits in 8 patients, including sinusitis (one; resolved without treatment), subglottic stenosis (one; required reconstructive surgery), persistent cough (three; all resolved spontaneously), occipital breakdown because of ET ties (one; healed after 1 month), soft voice (two; resolved spontaneously), and decreased pharyngeal sensation (one; resolved without treatment). Translaryngeal intubation is a safe and effective method to provide long-term ventilatory support in children.

Management of background pain and anxiety in critically burned children requiring protracted mechanical ventilation.

Optimal control of pain and anxiety is an elusive but important goal in children with protracted critical illness. This review represents an effort to document the doses of background medication required to achieve this goal in a group of children managed under a pain and anxiety protocol that adjusts background infusions to comfort. The course of children with wounds involving at least 10% of the body surface and coincident respiratory failure requiring mechanical ventilation for more than 7 days managed 1 Jan 97 to 31 Dec 98 was reviewed. A pain and anxiety protocol was used, including background infusions of morphine and midazolam adjusted to comfort. These 28 children had a mean (+/- standard deviation) age of 5.3 +/- 4.6 years, wound size of 48.3 +/- 28.4%, and were intubated for 25.0 +/- 23.9 days. Neuromuscular blocking drugs were administered for 65 of 447 (14.5%) ventilator days. To maintain comfort, drugs were required at doses substantially above standard dosing schemes. The highest daily background infusion of morphine sulfate averaged 0.40 mg/kg/hr +/- 0.24 mg/kg/hr (usual starting dose was 0.05 to 0.1 mg/kg/hr) and was reached 14.1 +/- 12.8 days after admission. The highest daily background infusion of midazolam averaged 0.15 +/- 0.07 mg/kg/hr (usual starting dose was 0.04 mg/kg/hr) and was reached 14.0 +/- 3.8 days after admission. Morphine infusions at extubation averaged 0.22 +/- 0.17 mg/kg/hr and midazolam infusions 0.10 +/- 0.12 mg/kg/hr. All children survived to discharge and there was no perceived morbidity related to these high doses of medication. Children with serious burns and respiratory failure will require high doses of background opiates and benzodiazepines to remain comfortable, because they develop drug tolerance during protracted critical illness. Infusions can be continued at a reduced dose through extubation, do not result in addiction or other apparent morbidity if adjusted to desired level of comfort, and may contribute to a reduced incidence of treatment-related stress disorders.