Percutaneous Dilatational Tracheostomy in a Cardiac Surgical Intensive Care Unit: A Single-Center Experience

Background

A significant proportion of cardiac surgery intensive care unit (CSICU) patients require long-term ventilation, necessitating tracheostomy placement. The goal of this study was to evaluate the long-term postoperative outcomes and complications associated with percutaneous dilatational tracheostomy (PDT) in CSICU patients.

Methods

All patients undergoing PDT after cardiac, thoracic, or vascular operations in the CSICU between January 1, 2013 and January 1, 2021 were identified. They were evaluated for mortality, decannulation time, and complications including bleeding, infection, and need for surgical intervention. Multivariable regression models were used to identify predictors of early decannulation and the complication rate.

Results

Ninety-three patients were identified for this study (70 [75.3%] male and 23 [24.7%] female). Furthermore, 18.3% of patients had chronic obstructive pulmonary disease (COPD), 21.5% had history of stroke, 7.5% had end-stage renal disease, 33.3% had diabetes, and 59.1% were current smokers. The mean time from PDT to decannulation was 39 days. Roughly one-fifth (20.4%) of patients were on dual antiplatelet therapy and 81.7% had anticoagulation restarted 8 hours post-tracheostomy. Eight complications were noted, including 5 instances of bleeding requiring packing and 1 case of mediastinitis. There were no significant predictors of decannulation prior to discharge. Only COPD was identified as a negative predictor of decannulation at any point in time (hazard ratio, 0.28; 95% confidence interval, 0.08-0.95; p=0.04).

Conclusion

Percutaneous tracheostomy is a safe and viable alternative to surgical tracheostomy in cardiac surgery ICU patients. Patients who undergo PDT have a relatively short duration of tracheostomy and do not have major post-procedural complications.

Trends of utilization and perioperative outcomes of robotic and video-assisted thoracoscopic surgery in patients with lung cancer undergoing minimally invasive resection in the United States

OBJECTIVE

The objective of this study was to evaluate utilization and perioperative outcomes of video-assisted thoracoscopic surgery (VATS) or robotic-assisted thoracoscopic surgery (RATS) for lung cancer in the United States using a nationally representative database.

METHODS

Hospital admissions for lobectomy or sublobar resection (segmentectomy or wedge resection) using VATS or RATS in patients with nonmetastatic lung cancer from October 2015 through December 2018 in the National Inpatient Sample were studied. Patient and hospital characteristics, perioperative complications and mortality, length of stay (LOS), and total hospital cost were compared. Logistic regression was used to assess whether the surgical approach was independently associated with adverse outcomes.

RESULTS

There were 83,105 patients who had VATS (n = 65,375) or RATS (n = 17,710) for lobectomy (72.7% VATS) or sublobar resection (84.2% VATS). Utilization of RATS for lobectomy and sublobar resection increased from 19.2% to 34% and 7.3% to 22%, respectively. Mortality, LOS, and conversion rates were comparable. The cost was higher for RATS (P <.01). Multivariate analyses showed comparable RATS and VATS complications with no independent association between the minimally invasive surgery approach used and adverse surgical outcomes, except for a decreased risk of pneumonia with RATS, relative to VATS sublobar resection (P <.01). Thoracic complication rates and LOS decreased after RATS lobectomy in 2018, compared with previous years (P <.005).

CONCLUSIONS

The utilization of robotic-assisted lung resection for cancer has increased in the United States between 2015 and 2018 for sublobar resection and lobectomy. In adjusted regression analysis, compared with VATS, patients who underwent RATS had similar complication rates and LOS. The robotic approach was associated with increased total hospital cost. LOS and thoracic complication rates trended down after RATS lobectomy.

Utilization of Supplemental Regional Anesthesia in Lobectomy for Lung Cancer in the United States: A Retrospective Study

Background

Pulmonary lobectomy is the standard of care for the treatment of early-stage non-small cell lung cancer. This study investigated the rate of utilization of supplemental anesthesia in patients undergoing video-assisted thoracoscopic surgery (VATS) or open lobectomy using a national database and assessed the effect of regional block (RB) on postoperative outcomes.

Methods

Patients who underwent lobectomy for lung cancer between 2014–2019 were identified in the American College of Surgeons National Surgical Quality Improvement Program. The patients’ primary mode of anesthesia and supplemental anesthesia were recorded. Preoperative characteristics and postoperative outcomes were compared between 2 surgical groups those who underwent general anesthesia (GA) alone versus GA with RB. Multivariable regression analyses were performed on the outcomes of interest.

Results

In total, 13,578 patients met the study criteria, with 87% undergoing GA and the remaining 13% receiving GA and RB. The use of neuraxial anesthesia decreased over the years, while RB use increased up to 20% in 2019. Age, body mass index, and preoperative comorbidities were comparable between groups. Patients who underwent VATS were more likely to receive RB than those who underwent thoracotomy. RB was most often utilized by thoracic surgeons. An adjusted analysis showed that RB use was associated with shorter hospital stays and a reduced likelihood of prolonged length of stay, but a higher rate of surgical site infections (SSIs).

Conclusion

In a large surgical database, there was underutilization of supplemental anesthesia in patients undergoing lobectomy for lung cancer. RB utilization was associated with a shorter length of hospital stay and an increase in SSI incidence.

Donation after cardiac death in heart transplantation: is there an ethical dilemma?

PURPOSE OF REVIEW

In an attempt to address the organ shortages in heart transplantation, USA centres have begun utilizing donation after cardiac death (DCD) as an alternative to traditional donation after brain death (DBD). As this paradigm continues to expand, there is a need to address the medico-legal and ethical aspects of DCD donation, which is the focus of the current review.

RECENT FINDINGS

Current protocols use criteria established by the Uniform Determination of Death Act (UDDA), which is explicit in defining the irreversibility of circulation and brain function in determining death. By the nature of DCD, the patient may not meet death criteria from a biological systems perspective of irreversibility, and thus, the moral dilemma ensues on whether removing vital organs violates our legal and moral obligations to the patient.

SUMMARY

In the current article, we review the ethical issues raised with DCD and define DCD protocols and their ability to comply with established regulatory guidelines while respecting the wishes of patients and their surrogates through informed decisions making about organ donation and end-of-life care.

Trends in open lobectomy outcomes for lung cancer over the last 15 years: national cohort

OBJECTIVE

Adoption of thoracoscopic lobectomy has been increasing in the US; however, open lobectomy (OL) is still performed in half of the cases. Postoperative care and enhanced recovery after surgery (ERAS) pathways have evolved and improved outcomes. The study aims to evaluate postoperative outcomes of OL over the last 15 years.

METHODS

Patients who underwent lobectomy for lung cancer between 2005 and 2019 were identified in the National Surgical Quality Improvement Program and divided into three groups; pre-ERAS (2005-2011), transitional period (2012-2015), and wider ERAS implementation (2016-2019). Preoperative characteristics and postoperative outcomes were compared and multivariable regression analysis was constructed to assess independent predictors of outcomes.

RESULTS

OL was comprised of 40% of lobectomies for lung cancer. 10,021 patients met inclusion criteria. 49% were males and mean age was 67. Patients who belonged to the (2016-2019) period group had significantly higher comorbidities and ASA classification. General surgeons performed < 10% of OL in 2016-2019 compared to over 30% during 2005-2011. Patients in the 2016-2019 period were less likely to experience unplanned intubation, surgical site infections, and sepsis. Mortality was also significantly lower than the previous groups (1.9% vs 2.0% and 2.8%, p = 0.05). The rate of discharge to facility as well as length of hospital stays improved over the years. The surgeon specialty served as an independent predictor for length of stay, unplanned intubation, and home discharge.

CONCLUSION

The outcomes of OL are improving over the years. Increasing number of these surgeries being performed by dedicated thoracic surgeons and ERAS pathways are likely helping improve outcomes.

First, We Do Harm: Obtaining Informed Consent for Surgical Procedures

Although many believe that the phrase “First, do no harm” was part of the Hippocratic Oath, in fact it was not. This phrase, often written in Latin (“Primum non Nocere”), seems to have first appeared in medical writing in the 17th century. However, it is obvious that many therapeutic interventions do cause at least some harm with hopes of benefitting patients in the long run. This balancing of initial harm in hope of eventual benefit is never more apparent than in the case of invasive procedures, though other examples abound, such as the administration of chemotherapy. The ethical concept of nonmaleficence, which traces its origins to the concept of primum non nocere, accurately acknowledges the concept of the need to strive to do more good than harm. Thus, it is apparent that, in a surgical operation, the surgeon is proposing to cause harm, initially, to the patient in hopes of creating an outcome that results in more good than harm. Therefore, the process of obtaining consent from the patient for a surgical operation acknowledges the fact that harm will, in fact, be inflicted on that patient, with the hope that, on balance, this harm will result in a greater overall good for the patient. It is for this reason that the modern concepts of informed consent have developed.

Lung transplantation for high-risk patients with idiopathic pulmonary fibrosis

BACKGROUND

Survival for patients with idiopathic pulmonary fibrosis (IPF) and high lung allocation score (LAS) values may be significantly reduced in comparison to those with lower LAS values.

OBJECTIVES

To evaluate outcomes for high-risk IPF patients as defined by LAS values ≥46 (N=42) versus recipients with LAS values <46 (N=89).

METHODS

We retrospectively reviewed records of 131 consecutive patients with IPF who received lung transplants at our institution between 1999 and 2013.

RESULTS

The mean LAS was significantly higher (59.5, interquartile range 43.9-75.9 vs. 39.3, interquartile range 37.7-44.3; p<0.01) for the high-risk cohort. The higher LAS cohort had significantly lower percent predicted forced vital capacity (FVC) versus recipients with LAS <46 (41.3±14.1% vs. 53.2±16.2%; p<0.01) and required more supplemental oxygen (7±5 vs. 4±2 L/min, p<0.01) prior to transplant versus recipients with LAS <46. Although the incidence of early post-LTX pulmonary complications was increased for the higher LAS group versus recipients with LAS <46, 30-day mortality and actuarial survival did not differ between the two cohorts.

CONCLUSIONS

Although lung transplantation in patients with IPF and high LAS values is associated with increased risk of early post-transplant complications, long-term post-transplant survival for our high-LAS cohort was equivalent to that for the lower LAS recipients.

Timing and Frequency of Unplanned Readmissions After Lung Transplantation Impact Long-Term Survival

BACKGROUND

Adverse events that require hospital readmission frequently occur long after lung transplantation (LT) that has been successfully performed. We sought to identify the causes and rate of unplanned readmissions after LT and to determine whether unplanned readmissions have a significant impact on post-LT survival.

METHODS

We retrospectively reviewed the outcomes in 174 LT recipients who underwent LT at our center from June 2005 to May 2014. The median follow-up period was 38 months (range, 17 to 72 months).

RESULTS

One hundred sixty (92%) of the 174 recipients were readmitted 854 times (5.3 times per patient). The median time to first readmission was 71 days (interquartile range [IQR], 28 to 240 days), and the median hospital length of stay at readmission was 3 days (IQR, 2 to 6 days). Freedom from first readmission was observed for 65% of patients at 1 month, 48% at 3 months, 43% at 6 months, and 26% at 12 months. Gender, lung allocation score, body surface area, year of transplantation, air leak longer than 5 days after operation, and allograft function were risk factors for readmission. The causes of readmission included infections (33%), respiratory adverse events (18%), rejection (15%), gastrointestinal events (15%), renal dysfunction (5%), and cardiac events (4%). Patients who died were found to have had early readmissions (p = 0.04) and more frequent readmissions (p = 0.001).

CONCLUSIONS

The first year after LT remains a high-risk period for unplanned readmissions regardless of pretransplantation diagnosis. Readmissions soon after discharge at index hospitalization and multiple readmissions are associated with an increased risk of mortality.

Environmental Exposures-The Missing Link in Immune Responses After Transplantation

In transplantation, immunosuppression has been directed at controlling acute responses, but treatment of chronic rejection has been ineffective. It is possible that factors that have previously been unaccounted for, such as exposure to inhaled pollution, ultraviolet light, or loss of the normal equilibrium between the gut immune system and the outside environment may be responsible for shifting immune responses to an effector/inflammatory phenotype, which leads to loss of self-tolerance and graft acceptance, and a shift towards autoimmunity and chronic rejection. Cells of the immune system are in a constant balance of effector response, regulation, and quiescence. Endogenous and exogenous signals can shift this balance through the aryl hydrocarbon receptor, which serves as a thermostat to modulate the response one way or the other, both at mucosal surfaces of interface organs to the outside environment, and in the internal milieu. Better understanding of this balance will identify a target for maintenance of self-tolerance and continued graft acceptance in patients who have achieved a "steady state" after transplantation.

Upregulation of aryl hydrocarbon receptor expression in CD4 T lymphocytes during an immune response in vivo. (INM1P.431)

Activation of the aryl hydrocarbon receptor (AHR) can impact T-cell differentiation and the maintenance of tissue-resident T cells. AHR expression, measured by RT-PCR or Western blot has been shown to be low in most CD4 T-cell subsets with highest expression found after stimulation of naïve CD4 T cells under Th17 conditions in vitro. The current study measures AHR expression within CD4 T-cell subsets of naïve or skin-grafted mice using flow cytometry. Cells were freshly isolated from the spleen, lymph nodes or skin of either untreated mice or mice that underwent allogeneic skin transplant. AHR expression in cells from untreated mice was highest in IL-17A+ CD4 T cells, followed by FoxP3+ and IFNγ+ cells. Naïve, CD62L+ CD4 T cells had the lowest expression. AHR expression in splenic or lymph node CD4 T cells from skin-grafted mice was similar to naïve mice with 20 - 30 % of FoxP3+ and &lt;10% of FoxP3- being AHR+. However, CD4 T cells within the skin grafts showed elevated AHR expression compared to spleen or LN with 75 - 85 % of FoxP3+ and 40 - 70% of FoxP3- being AHR+. This is comparable to the &gt;90% AHR+ CD4 T cells found when splenocytes were stimulated in vitro with anti-CD3 antibody in the presence of TGFb and IL-6. We conclude that the up-regulation of AHR expression in CD4 T cells in vitro also happens during immune responses in vivo and is not restricted to a single T cell subset, and may be important in T cell differentiation, trafficking, and cytokine production.

Supplementation of the aryl hydrocarbon receptor ligand indole-3-carbinol protects mice from Clostridium difficult associated disease. (MUC5P.762)

We have previously presented the dramatic benefit in survival that the dietary aryl hydrocarbon receptor (AHR) ligand indole-3-carbinol (I3C) confers in C. difficile disease in mice. Other groups have demonstrated that γδ T cells and Tregs play an important role in preventing other models of colitis. The current study sought to determine whether dietary I3C could protect mice from C. difficile by increasing the amounts of protective γδ T cells and Tregs. Furthermore, we examined the role of I3C in preventing antibiotic mediated dysbiosis. Mice were fed an experimental AHR ligand free diet (“base”) or the same diet supplemented with I3C and then infected with C. difficile. Pre-infection, base mice had less γδ T cells and Tregs in their cecum compared to I3C mice. Furthermore, I3C mice had a more robust and less pathologic microbiome pre-infection. Post-infection, I3C mice continued to have higher levels of γδ T cells and Tregs. These data suggest that AHR ligand supplementation can protect the host from C. difficile by reducing antibiotic associated dysbiosis as well as augmenting the local immune system to be more protective from C. difficile associated inflammation. Given the poor treatment options currently available as well as the high morbidity of infection, this represents an exciting new therapeutic possibility.

Exposure to inhaled atmospheric particulate matter enhances autoimmunity. (BA6P.125)

Epidemiological studies have demonstrated a relationship between exposure to atmospheric particulate matter (PM) and autoimmune disease. Multiple mechanisms have been proposed, including our research showing PM exposure in vitro can enhance Th17 differentiation in an aryl hydrocarbon receptor-dependent manner. The current study sought to determine the impact of PM exposure in vivo on immunity outside of the lung. In the 1st experiment, male B6 mice (n = 4 per group) were treated every 3 days with either vehicle or 800ug of SRM1949b, a representative sample of urban dust particles, in 20ul PBS i.n. for a total of 5 doses. One day after the last dose, splenocytes were cultured for 4 days with anti-CD3 and cytokines were measured. Treatment with PM increased IL-17A 3-fold but had no impact on IFNγ expression. In the 2nd experiment, female B6 mice (n = 4 per group) were treated every 3 days with vehicle or PM for a total of 9 doses. On the day of the 5th dose, a standard EAE protocol commenced. Clinical scoring using a 5-point scale began on d7 and ended on d21. All mice in both groups displayed EAE symptoms. Mice treated with PM had significantly higher mean peak score (3.5 + 0.3 vs 2.5 + 0.3 for PBS), trended toward having a higher mean clinical score and had earlier onset of disease. Together, these data suggest that inhaled PM exposure can impact immune responses beyond the lung, and support a mechanism where inhaled pollution aggravates autoimmunity.

The aryl hydrocarbon receptor meets immunology: friend or foe? A little of both

The aryl hydrocarbon receptor (AHR) has long been studied by toxicologists as a ligand-activated transcription factor that is activated by dioxin and other environmental pollutants such as polycyclic aromatic hydrocarbons (PAHs). The hallmark of AHR activation is the upregulation of the cytochrome P450 enzymes that metabolize many of these toxic compounds. However, recent findings demonstrate that both exogenous and endogenous AHR ligands can alter innate and adaptive immune responses including effects on T-cell differentiation. Kynurenine, a tryptophan breakdown product, is one such endogenous ligand of the AHR. Expression of indoleamine 2,3-dioxygenase by dendritic cells causes accumulation of kynurenine and results in subsequent tolerogenic effects including increased regulatory T-cell activity. At the same time, PAHs found in pollution enhance Th17 differentiation in the lungs of exposed mice via the AHR. In this perspective, we will discuss the importance of the AHR in the immune system and the role this might play in normal physiology and response to disease.

Venovenous extracorporeal membrane oxygenation in patients with atrial septal defects

Two patients presented in profound respiratory distress unresponsive to maximal support and were placed on venovenous ECMO. Subsequently, both were found to have a patent foramen ovale and high pulmonary artery pressures, resulting in a right to left shunt. Both patients had a better than expected response to ECMO, likely related to their shunts allowing oxygenated blood to bypass the high pulmonary artery pressures and go directly to the left heart. Both patients were successfully weaned from ECMO and discharged to home in good condition.

Exposure to atmospheric particulate matter enhances Th17 polarization through the aryl hydrocarbon receptor

Lung diseases, including asthma, COPD, and other autoimmune lung pathologies are aggravated by exposure to particulate matter (PM) found in air pollution. IL-17 has been shown to exacerbate airway disease in animal models. As PM is known to contain aryl hydrocarbon receptor (AHR) ligands and the AHR has recently been shown to play a role in differentiation of Th17 T cells, the aim of this study was to determine whether exposure to PM could impact Th17 polarization in an AHR-dependent manner. This study used both cell culture techniques and in vivo exposure in mice to examine the response of T cells to PM. Initially experiments were conducted with urban dust particles from a standard reference material, and ultimately repeated with freshly collected samples of diesel exhaust and cigarette smoke. The readout for the assays was increased T cell differentiation as indicated by increased generation of IL-17A in culture, and increased populations of IL-17 producing cells by intracellular flow cytometry. The data illustrate that Th17 polarization was significantly enhanced by addition of urban dust in a dose dependent fashion in cultures of wild-type but not AHR^-/- mice. The data further suggest that polycyclic aromatic hydrocarbons played a primary role in this enhancement. There was both an increase of Th17 cell differentiation, and also an increase in the amount of IL-17 secreted by the cells. In summary, this paper identifies a novel mechanism whereby PM can directly act on the AHR in T cells, leading to enhanced Th17 differentiation. Further understanding of the molecular mechanisms responsible for pathologic Th17 differentiation and autoimmunity seen after exposure to pollution will allow direct targeting of proteins involved in AHR activation and function for treatment of PM exposures.

Foot muscle energy reserves in diabetic patients without and with clinical peripheral neuropathy

OBJECTIVE To investigate changes in the foot muscle energy reserves in diabetic non-neuropathic and neuropathic patients. RESEARCH DESIGN AND METHODS We measured the phosphocreatinine (PCr)/inorganic phosphate (Pi) ratio, total (31)P concentration, and the lipid/water ratio in the muscles in the metatarsal head region using MRI spectroscopy in healthy control subjects and non-neuropathic and neuropathic diabetic patients. RESULTS The PCr/Pi ratio was higher in the control subjects (3.23 +/- 0.43) followed by the non-neuropathic group (2.61 +/- 0.36), whereas it was lowest in the neuropathic group (0.60 +/- 1.02) (P < 0.0001). There were no differences in total (31)P concentration and lipid/water ratio between the control and non-neuropathic groups, but both measurements were different in the neuropathic group (P < 0.0001). CONCLUSIONS Resting foot muscle energy reserves are affected before the development of peripheral diabetic neuropathy and are associated with the endothelial dysfunction and inflammation.