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Patients who require mechanical ventilation secondary to severe COVID-19 infection have poor survival. It is unknown if the benefit of tracheostomy extends to COVID-19 patients. If so, what is the optimal timing?Retrospective cohort study within a large hospital system in the United States. The population included patients with COVID-19 from January 1, 2020 to September 30, 2020. In total, 93,918 cases were identified. They were excluded if no intubation or tracheostomy, underwent tracheostomy before intubation,18 years old, hospice patients before admission, and bacterial pneumonia. In total, 5,911 patients met the criteria. Outcomes between patients who underwent endotracheal intubation only versus tracheostomy were compared. The primary outcome was inpatient mortality. All patients who underwent tracheostomy versus intubation only were compared. Three cohort analysis compared early (10 days) versus late (10 days) tracheostomy versus control. Eight cohort analysis compared days 0-2, days 3-6, days 7-10, days 11-14, days 15-18, days 19-22, and days 23+ to tracheostomy versus control.There was an overall inpatient mortality rate of 37.5% in the tracheostomy cohort compared to 54.4% in the control group (P.0001). There was an early tracheostomy group inpatient mortality rate of 44.7% (adjusted odds ratio 0.73, 95% confidence interval 0.52-1.01) compared to 33.1% (adjusted odds ratio 0.44, 95% confidence interval 0.34-0.58) in the late tracheostomy group.COVID-19 patients with tracheostomy had a significantly lower mortality rate compared to intubated only. Optimal timing for tracheostomy placement for COVID-19 patients is 11 days or later. Future studies should focus on early tracheostomy patients.

Knowledge of respiratory mechanics is fundamental for correct use of mechanical ventilation and full understanding of the impact of lung disease during anesthetic administration. The role of the respiratory system is to deliver oxygen to cells so that respiration can occur. To accomplish this task, the respiratory system during spontaneous breathing generates negative pressure differentials able to overcome airway and tissue resistance, allowing inspiration. In contrast, mechanical ventilation uses positive pressure differentials between the mouth and the alveoli to inflate the lungs and allow for inspiration. The work of breathing, which is responsible for the energy consumption required for respiration, should be kept to a minimum. Increases in work of breathing can lead to fatigue and respiratory failure.

Biphasic positive airway pressure (BiPAP), airway pressure release ventilation (APRV), and prone ventilation are used as rescue therapies for refractory hypoxemia in patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). BiPAP and its variant, APRV, allow the patient to breathe spontaneously at two levels of continuous positive airway pressure (CPAP). BiPAP uses conventional I:E ratios, while APRV is an inverse ratio ventilation. The significant advantages of these two modes of ventilation are the preservation of spontaneous breathing, improved ventilation-perfusion matching, use of lower peak pressure, and better oxygenation. Ventilation in the prone position determines a rapid and sustained improvement in oxygenation in patients with ALI/ARDS. Mechanisms that can explain its beneficial effects include a reduced pleural pressure gradient with more uniform lung inflation and improved lung recruitment, an increase in functional residual capacity, redistribution of regional lung perfusion, variations in diaphragm movement, and better clearance of secretions.

Cardiac output is the amount of blood ejected from the ventricles with each cardiac cycle. The pulmonary artery catheter has been the mainstay in assessing cardiac output for decades. Its routine use carries potential risks of right ventricular perforation, pulmonary artery rupture, and/or embolization. Echocardiography, esophageal Doppler, transpulmonary thermodilution, and pulse wave analysis are alternative methods to assess cardiac output. To properly assess the cardiac output in surgical and critically ill patients, it is of great importance to become familiar with the chosen technique and its pitfalls. Nevertheless, estimating the cardiac output in patients is important for anesthesiologists and intensivists in order to ensure adequate oxygen delivery and tissue perfusion.

Mixed venous oxygen saturation (SvO2) is the percentage of oxygenated hemoglobin in the blood returning to the right side of the heart. SvO2 reflects the balance between oxygen delivery and oxygen consumed by tissues. Normally, SvO2 is 65%–75%. SvO2 can be measured with intermittent blood samples from the pulmonary artery or continuously with the use of oximetric catheters. Determinants of SvO2 are cardiac output, hemoglobin concentration, arterial oxygen saturation, and oxygen consumption. A decrease in oxygen delivery (e.g., cardiogenic shock, anemia, hypoxemia) or increase in oxygen demand (e.g., hyperthermia, shivering, malignant hyperthermia) causes a drop in SvO2. An increase in oxygen delivery (e.g., increased cardiac output, hyperoxia) and decrease in oxygen demand (e.g., hypothermia, anesthesia) cause high SvO2 values. SvO2 in combination with other clinical information can help to identify global tissue hypoxia during the perioperative period and in critically ill patients.

Mechanical ventilation provides an artificial lung support that completely or partially supports the work carried by respiratory muscles. It is indicated in patients with inadequate respiratory drive, hypoxia, and failure to maintain adequate ventilation. Delivery of air into the lung under positive pressure via an artificial airway (endotracheal tube/tracheostomy tube) is referred to as invasive ventilation. Noninvasive ventilation uses a different interface (mask) and provides support without invasive artificial airway. The mode of mechanical ventilation defines the relationship between the type of breath (spontaneous, assisted, or mandatory) and a group of control variables (volume, pressure) and phase variables (trigger, limit, cycle) that regulate the pattern of breath delivery. Modes of ventilation include assist control, SIMV (synchronized intermittent mandatory ventilation), pressure support, pressure controlled and inverse ratio, APRV (airway pressure release ventilation), and high-frequency ventilation.

Familial dysautonomia is a rare autosomal recessive neurodegenerative disease affecting cells of the autonomic nervous system. Patients with this disease are insensitive to pain but their autonomic nervous system is still activated with noxious stimuli. This report details a case of a patient with familial dysautonomia who underwent right ankle open reduction and internal fixation for a bimalleolar right ankle fracture. The patients preoperative and intraoperative course were uneventful but shortly after handoff to the intensive care unit, the patient experienced an autonomic crisis. Management of these patients is complex, requiring maintenance of physiologic homeostasis as well as preventing hemodynamic instability caused by noxious stimuli. Any deviations from baseline may cause an autonomic crisis, as happened in our patient. Herein, we detail the perioperative management of a patient with familial dysautonomia in further detail.

Transesophageal echocardiography (TEE) can be utilized for hemodynamic monitoring and resuscitation. In order to study the pattern of TEE use in trauma patients, a multi-institutional retrospective cohort study was performed comparing adult trauma patients who underwent TEE or those who underwent traditional invasive hemodynamic monitoring (TIHM). TIHM was defined as the use of arterial line, central venous line, or pulmonary artery catheter without TEE. Mortality rates were obtained and multivariable logistic regression was used to risk adjust for age, gender, race, insurance status, Glasgow coma scale (GCS), ICD Injury severity score (ICISS). Compared to TIHM group, more patients in TEE group had a history of congestive heart failure (CHF) or chronic pulmonary disease (CPD). Mortality rate was lower in the TEE group 7 versus 23% ( P-value < .0001). After adjusting for GCS and ICISS in multivariable analysis, inpatient mortality was significantly lower in the TEE cohort.