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In this chapter, the critical topic of congenital diaphragmatic hernia is reviewed. The diagnosis and pathophysiology are discussed in relation to organ systems effected and prognostic factors. The author covers the prenatal diagnostic evaluations as well as fetal interventions. The anesthetic implications and management of these patients if examined in detail from ventilatory goals to ECMO.
The impact of mechanical ventilation on the daily costs of intensive care unit (ICU) care is largely unknown. We thus conducted a systematic search for studies measuring the daily costs of ICU stays for general populations of adults (age ≥18 years) and the added costs of mechanical ventilation. The relative increase in the daily costs was estimated using random effects meta regression. The results of the analyses were applied to a recent study calculating the excess length-of-stay associated with ICU-acquired (ventilator-associated) pneumonia, a major complication of mechanical ventilation. The search identified five eligible studies including a total of 54 766 patients and ~238 037 patient days in the ICU. Overall, mechanical ventilation was associated with a 25.8% (95% CI 4.7%–51.2%) increase in the daily costs of ICU care. A combination of these estimates with standardised unit costs results in approximate daily costs of a single ventilated ICU day of €1654 and €1580 in France and Germany, respectively. Mechanical ventilation is a major driver of ICU costs and should be taken into account when measuring the financial burden of adverse events in ICU settings.
Preoperative mechanical ventilation is associated with morbidity and mortality following CHD surgery, but prior studies lack a comprehensive analysis of how preoperative respiratory support mode and timing affects outcomes.
We retrospectively collected data on children <18 years of age undergoing cardiac surgery at an academic tertiary care medical centre. Using multivariable regression, we examined the association between modes of preoperative respiratory support (nasal cannula, high-flow nasal cannula/noninvasive ventilation, or invasive mechanical ventilation), escalation of preoperative respiratory support, and invasive mechanical ventilation on the day of surgery for three outcomes: operative mortality, postoperative length of stay, and postoperative complications. We repeated our analysis in a subcohort of neonates.
A total of 701 children underwent 800 surgical procedures, and 40% received preoperative respiratory support. Among neonates, 243 patients underwent 253 surgical procedures, and 79% received preoperative respiratory support. In multivariable analysis, all modes of preoperative respiratory support, escalation in preoperative respiratory support, and invasive mechanical ventilation on the day of surgery were associated with increased odds of prolonged length of stay in children and neonates. Children (odds ratio = 3.69, 95% CI 1.2–11.4) and neonates (odds ratio = 8.97, 95% CI 1.31–61.14) on high-flow nasal cannula/noninvasive ventilation had increased odds of operative mortality compared to those on room air.
Preoperative respiratory support is associated with prolonged length of stay and mortality following CHD surgery. Knowing how preoperative respiratory support affects outcomes may help guide surgical timing, inform prognostic conversations, and improve risk stratification models.
Approximately 50,000 patients per year present at emergency departments (EDs) because of carbon monoxide (CO) intoxication. The hypothesis of this study was that the half-life of CO and the regression period of complaints could be reduced more rapidly by applying oxygen with the Continuous Positive Airway Pressure (CPAP) modality using a non-invasive mechanical ventilator.
The patients were divided into Group 1 and Group 2 in terms of the treatment method applied. Patients in Group 1 received FiO2 1.0 15 l/minute oxygen at room temperature for at least 30 minutes with a non-rebreather mask. Patients in Group 2 received FiO2 1.0 oxygen at 12 cmH2O pressure with non-invasive mechanical ventilation for at least 30 minutes with an oronasal mask in the CPAP modality.
The median values (interquartile range) of carboxyhemoglobin (COHb) levels at zero and 30 minutes of patients were 19% (8) and 14% (6) in Group 1 and 22% (8) and nine percent (3) in Group 2; a median difference of six percent (2) was detected in Group 1 and of 13% (4) in Group 2 in the first 30 minutes (P <.001). When the symptoms of the patients were examined, the median values of Group 1 and Group 2 at zero minutes were both eight units and at 30 minutes were five and three units, respectively. A decrease of five units was determined in the median of Group 2 in the first 30 minutes, and a decrease of two units in the median of Group 1 (P <.001).
The use of CPAP was determined to more rapidly reduce COHb level as opposed to high-flow oxygen therapy. It is also thought that it may enable earlier discharge by reducing the duration of the emergency follow-up since it provides a faster improvement in the symptoms of the patients.
Retraction pocket theory is the most acceptable theory for cholesteatoma formation. Canal wall down mastoidectomy is widely performed for cholesteatoma removal. Post-operatively, each patient with canal wall down mastoidectomy has an exteriorised mastoid cavity, exteriorised attic, neo-tympanic membrane and shallow neo-middle ear.
This study aimed to clinically assess the status of the neo-tympanic membrane and the exteriorised attic following canal wall down mastoidectomy.
All post canal wall down mastoidectomy patients were recruited and otoendoscopy was performed to assess the neo-tympanic membrane. A clinical classification of the overall status of middle-ear aeration following canal wall down mastoidectomy was formulated.
Twenty-five ears were included in the study. Ninety-two per cent of cases showed some degree of neo-tympanic membrane retraction, ranging from mild to very severe.
After more than six months following canal wall down mastoidectomy, the degree of retracted neo-tympanic membranes and exteriorised attics was significant. Eustachian tube dysfunction leading to negative middle-ear aeration was present even after the canal wall down procedure. However, there was no development of cholesteatoma, despite persistent retraction.
Ménière's disease often presents with aural fullness, for reasons that are currently not well understood. Transtympanic ventilation tube insertion has been historically used for the management of this symptom, though the nature and mechanism of effectiveness is unclear.
To give an overview of the data available on the effects of ventilation tube insertion on aural fullness in Ménière's disease.
The databases PubMed, Embase, Medline, Scopus, Web of Science, Central and Google Scholar were searched to identify relevant records. Records were subsequently analysed and data extracted.
Only two studies directly measured the effect of ventilation tube insertion on aural fullness, while three others measured it as a placebo to assess another treatment. Considerable heterogeneity was found amongst the studies, including conflicting conclusions.
There is a paucity of evidence investigating the effect of grommet insertion on aural fullness in Ménière's disease. This work directs future research into this topic.
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.
To describe the use of balloon dilation with non-invasive ventilation in the treatment of pregnant patients with idiopathic subglottic stenosis.
The medical charts of four consecutive patients who underwent jet ventilation or high-flow nasal cannula oxygenation with balloon dilation for the treatment of idiopathic subglottic stenosis during pregnancy were reviewed.
Objective improvement of subglottic stenosis was seen in all four cases, with end-result Myer–Cotton grade 1 lesions down from pre-procedure grade 3 lesions. Patients also reported subjective improvements in symptomatology, with no further airway issues. All patients delivered normally, at term.
Laryngeal dilation with continuous radial expansion pulmonary balloons using non-invasive ventilation for the treatment of idiopathic subglottic stenosis in pregnant patients is safe and efficacious, and should be the first line treatment option for this patient population. The improvement in symptoms, and lack of labour and pregnancy complications, distinguish this method of treatment from others reported in the literature.
Hyperventilation during cardiopulmonary resuscitation (CPR) negatively affects cardiopulmonary physiology. Compression-adjusted ventilations (CAVs) may allow providers to deliver ventilation rates more consistently than conventional ventilations (CVs). This study sought to compare ventilation rates between these two methods during simulated cardiac arrest.
That CAV will not result in different rates than CV in simulated CPR with metronome-guided compressions.
Volunteer Basic Life Support (BLS)-trained providers delivered bag-valve-mask (BVM) ventilations during simulated CPR with metronome-guided compressions at 100 beats/minute. For the first 4-minute interval, volunteers delivered CV. Volunteers were then instructed on how to perform CAV by delivering one breath, counting 12 compressions, and then delivering a subsequent breath. They then performed CAV for the second 4-minute interval. Ventilation rates were manually recorded. Minute-by-minute ventilation rates were compared between the techniques.
A total of 23 volunteers were enrolled with a median age of 36 years old and with a median of 14 years of experience. Median ventilation rates were consistently higher in the CV group versus the CAV group across all 1-minute segments: 13 vs 9, 12 vs 8, 12 vs 8, and 12 vs 8 for minutes one through four, respectively (P <.01, all). Hyperventilation (>10 breaths per minute) occurred 64% of the time intervals with CV versus one percent with CAV (P <.01). The proportion of time which hyperventilation occurred was also consistently higher in the CV group versus the CAV group across all 1-minute segments: 78% vs 4%, 61% vs 0%, 57% vs 0%, and 61% vs 0% for minutes one through four, respectively (P <.01, all).
In this simulated model of cardiac arrest, CAV had more accurate ventilation rates and fewer episodes of hyperventilation compared with CV.
Nikolla DA, Kramer BJ, Carlson JN. A cross-over trial comparing conventional to compression-adjusted ventilations with metronome-guided compressions. Prehosp Disaster Med. 2019;34(2):220–223
To determine the factors related to multiple ventilation tube insertions in children with otitis media with effusion.
A retrospective review was performed of 126 ears of 81 children aged less than 12 years who had undergone insertion of a Paparella type 1 ventilation tube for the first time between August 2012 and March 2018.
Mean age at the first operation was 4.0 ± 2.2 years, and the mean duration of otitis media with effusion before the first ventilation tube insertion was 5.4 ± 4.5 months. Among 126 ears, 80 (63.5 per cent) had a single ventilation tube insertion and 46 (36.5 per cent) had multiple insertions. On multivariate logistic regression, tympanic membrane retraction, serous middle-ear discharge, and early recurrence of otitis media with effusion were independent predictive factors of multiple ventilation tube insertions.
Tympanic membrane retraction, serous middle-ear discharge, and early recurrence of otitis media with effusion after the first tube extrusion are associated with multiple ventilation tube insertions.
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.
The cause of Eustachian tube dysfunction often remains unclear. Therefore, this study aimed to examine the feasibility and possible diagnostic use of optical coherence tomography in the Eustachian tube ex vivo.
Two female blackface sheep cadaver heads were examined bilaterally. Three conditions of the Eustachian tube were investigated: closed (resting position), actively opened and stented. The findings were compared (and correlated) with segmented histological cross-sections.
Intraluminal placement of the Eustachian tube with the optical coherence tomography catheter was performed without difficulty. Regarding the limited infiltration depth of optical coherence tomography, tissues can be differentiated. The localisation of the stent was accurate as was the lumen.
The application of optical coherence tomography in the Eustachian tube under these experimental conditions is considered to be a feasible, rapid and non-invasive diagnostic method, with possible diagnostic value for determining the luminal shape and superficial lining tissue of the Eustachian tube.
A gastrointestinal outbreak was reported among 154 diners who attended a Christmas buffet on the 9 and 10 December 2016. A retrospective cohort study was undertaken. Faecal samples, water, ice and an air ventilation device were tested for indicators and routine pathogens. Altogether 26% (24/91) fulfilled the case definition of having typical viral gastrointestinal symptoms. Norovirus genogroup I was detected in faecal samples from three cases. One of these cases tested positive also for sapovirus and had a family member testing positive for both norovirus and sapovirus. A diner who drank water or drinks with ice cubes (risk ratios (RR) 6.5, 95% confidence intervals (CI) 1.5–113.0) or both (RR 8.2, 95% CI 1.7–145.5) had an increased risk in a dose-response manner. Ice cubes from three vending machines had high levels of heterotrophic bacteria. A faulty air ventilation valve in the space where the ice cube machine was located was considered a likely cause of this outbreak. Leaking air ventilation valves may represent a neglected route of transmission in viral gastrointestinal outbreaks.
A double-blinded, randomised, placebo-controlled trial was conducted to determine whether routine pre-operative analgesia is beneficial in reducing post-operative ear pain following bilateral myringotomy and tube placement.
Forty-five children (aged 3–15 years) were randomised to receive either pre-operative analgesics (paracetamol and ibuprofen) (n = 21) or placebo (n = 24). All children underwent sevoflurane gas induction with intranasal fentanyl (2 mcg/kg) to reduce the incidence of emergence agitation. Post-operative pain scores were measured using the Wong-Baker Faces Pain Rating Scale. Median pain scores taken 90 minutes post-surgery, and the highest pain score recorded prior to 90 minutes, were analysed.
There were no statistical differences between the median pain scores at 90 minutes or subsequent need for rescue analgesia. Emergence agitation did not occur in any child. Inadvertent ear trauma, use of an intravenous cannula or airway adjunct did not affect pain scores.
Routine pre-operative analgesia does not reduce pain scores in the early post-operative period. Simple analgesics are effective for rescue analgesia in the minority of cases.
Background: Non-invasive ventilation (NIV) improves quality of life and survival in patients with amyotrophic lateral sclerosis (ALS) and respiratory symptoms. Little is known about the patterns of NIV use over time and the impact of NIV on end-of-life decision-making in ALS. Objective: This study assessed the pattern of NIV use over the course of the disease and the timing of end-of-life discussions in people living with ALS. Method: A retrospective single-center cohort study was performed at London Health Sciences Centre. Daily NIV duration of use was evaluated at 3-month intervals. The timing of diagnosis, NIV initiation, discussions relating to do-not-attempt-resuscitation (DNAR) and death were examined. Results: In total, 48 patients were included in the analysis. Duration of NIV use increased over time, and tolerance to NIV was observed to be better than expected in patients with bulbar-onset ALS. There was a high degree of variability in the timing of end-of-life discussions in patients with ALS (356±451 days from diagnosis). In this cohort, there was a strong association between the timing of discussions regarding code status and establishment of a DNAR order (r2=0.93). Conclusion: This retrospective cohort study suggests that the use of NIV in ALS increases over time and that there remains a great deal of variability in the timing of end-of-life discussions in people living with ALS. Future prospective studies exploring the use NIV over the disease trajectory and how NIV affects end-of-life decision-making in people with ALS are needed.
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.
This article focuses on the consolidation of naval hygiene practices during the Victorian era, a period of profound medical change that coincided with the fleet’s transition from sail to steam. The ironclads of the mid- to late- nineteenth century offered ample opportunities to improve preventive medicine at sea, and surgeons capitalised on new steam technologies to provide cleaner, dryer, and airier surroundings below decks. Such efforts reflected the sanitarian idealism of naval medicine in this period, inherited from the eighteenth-century pioneers of the discipline. Yet, despite the scientific thrust of Victorian naval medicine, with its emphasis on collecting measurements and collating statistics, consensus about the causes of disease eluded practitioners. It proved almost impossible to eradicate sickness at sea, and the enclosed nature of naval vessels showed the limitations – rather than the promise – of attempting to enforce absolute environmental controls. Nonetheless, sanitarian ideology prevailed throughout the steam age, and the hygienic reforms enacted throughout the fleet showed some of the same successes that attended the public health movement on land. It was thus despite shifting ideas about disease and new methods of investigation that naval medicine remained wedded to its sanitarian roots until the close of the nineteenth century.
Chemical-biological-radio-nuclear (CBRN) gas masks are the standard means for protecting the general population from inhalation of toxic industrial compounds (TICs), for example after industrial accidents or terrorist attacks. However, such gas masks would not protect patients on home mechanical ventilation, as ventilator airflow would bypass the CBRN filter. We therefore evaluated in vivo the safety of adding a standard-issue CBRN filter to the air-outflow port of a home ventilator, as a method for providing TIC protection to such patients.
Eight adult patients were included in the study. All had been on stable, chronic ventilation via a tracheostomy for at least 3 months before the study. Each patient was ventilated for a period of 1 hour with a standard-issue CBRN filter canister attached to the air-outflow port of their ventilator. Physiological and airflow measurements were made before, during, and after using the filter, and the patients reported their subjective sensation of ventilation continuously during the trial.
For all patients, and throughout the entire study, no deterioration in any of the measured physiological parameters and no changes in measured airflow parameters were detected. All patients felt no subjective difference in the sensation of ventilation with the CBRN filter canister in situ, as compared with ventilation without it. This was true even for those patients who were breathing spontaneously and thus activating the ventilator’s trigger/sensitivity function. No technical malfunctions of the ventilators occurred after addition of the CBRN filter canister to the air-outflow ports of the ventilators.
A CBRN filter canister can be added to the air-outflow port of chronically ventilated patients, without causing an objective or subjective deterioration in the quality of the patients’ mechanical ventilation. (Disaster Med Public Health Preparedness. 2018;12:739-743)
To explore the link between nasal polyposis, refractory otitis media with effusion and eosinophilic granulomatosis with polyangiitis.
A retrospective observational study was carried out of patients diagnosed with refractory otitis media with effusion necessitating grommet insertion and who had nasal polyps. Patients were evaluated to determine if they fulfilled the diagnostic criteria of eosinophilic granulomatosis with polyangiitis.
Sixteen patients (10 males and 6 females) were identified. The mean age of grommet insertion was 45.4 years. The mean number of grommets inserted per patient was 1.6. The mean number of nasal polypectomies was 1.7. All 16 patients had paranasal sinus abnormalities and otitis media with effusion, 14 had asthma, 9 had serological eosinophilia and 7 had extravascular eosinophilia. Nine patients met the diagnostic criteria for eosinophilic granulomatosis with polyangiitis.
The co-presence of nasal polyps and resistant otitis media with effusion should raise the possibility of eosinophilic granulomatosis with polyangiitis.