Faculty Bibliography

With the growth of the older adult population, the number of older adults waitlisted for and undergoing kidney and liver transplantation has increased. Transplantation is an important and definitive treatment for this population. We present a contemporary review of the unique preoperative, intraoperative, and postoperative issues that patients older than 65 y face when they undergo kidney or liver transplantation. We focus on geriatric syndromes that are common in older patients listed for kidney or liver transplantation including frailty, sarcopenia, and cognitive dysfunction; discuss important considerations for older transplant recipients, which may impact preoperative risk stratification; and describe unique challenges in intraoperative and postoperative management for older patients. Intraoperative challenges in the older adult include using evidence-based best anesthetic practices, maintaining adequate perfusion pressure, and using minimally invasive surgical techniques. Postoperative concerns include controlling acute postoperative pain; preventing cardiovascular complications and delirium; optimizing immunosuppression; preventing perioperative kidney injury; and avoiding nephrotoxicity and rehabilitation. Future studies are needed throughout the perioperative period to identify interventions that will improve patients' preoperative physiologic status, prevent postoperative medical complications, and improve medical and patient-centered outcomes in this vulnerable patient population.

BACKGROUND:Kidney transplant (KT) candidates often experience hospitalizations, increasing their delirium risk. Hospitalizations and delirium are associated with worse post-KT outcomes, yet their relationship with pre-KT outcomes is less clear. Pre-KT delirium may worsen access to KT due to its negative impact on cognition and ability to maintain overall health. METHODS:Using a prospective cohort of 2374 KT candidates evaluated at a single center (2009-2020), we abstracted hospitalizations and associated delirium records after listing via chart review. We evaluated associations between waitlist mortality and likelihood of KT with hospitalizations and hospitalized delirium using competing risk models and tested whether associations differed by gerontologic factors. RESULTS: < 0.001), with those aged ≥65 having a 61% lower likelihood of KT. CONCLUSION/CONCLUSIONS:Hospitalization and delirium are associated with worse pre-KT outcomes and have serious implications on candidates' access to KT. Providers should work to reduce preventable instances of delirium.

Acute limb ischemia caused by peripheral venoarterial extracorporeal membrane oxygenation (ECMO) cannulation is associated with increased mortality. Early detection of limb hypoperfusion may lead to timely intervention and prevent irreversible muscle damage. Methods to determine the adequacy of tissue oxygenation in cannulated extremities include bedside physical examination, trending serum biochemical markers, and somatic near-infrared spectroscopy. To prevent ECMO-related limb ischemia events, interventions include the addition of distal antegrade perfusion catheters to the arterial ECMO canula, minimizing arterial cannula diameter, placing arterial and venous cannulae on opposite extremities, and adding a side-arm graft to the cannulated artery. If the limb develops early signs of ischemia, preventative measures such as distal perfusion catheter insertion or changing the location of the arterial cannula should be performed. Acute compartment syndrome requires emergency fasciotomy or amputation if the limb is unsalvageable. Opportunities for future research include improving monitoring technology and standardizing the use of the distal perfusion catheter.

BACKGROUND:Ideal timing of postoperative beta-blockers is unclear. We hypothesized that patients who do not receive beta-blockers immediately after cardiac surgery would have increased in-hospital mortality (primary outcome) and postoperative hemodynamic, pulmonary, neurologic, or respiratory complications (secondary outcomes). METHODS:We performed a retrospective cohort study evaluating patients who underwent cardiac surgery at our institution from January 1, 2013 to September 30, 2017. We compared outcomes between patients who received beta-blockers by postoperative day (POD) 5 with outcomes in patients who did not receive beta-blockers at any time or received them after POD 5. Inverse probability of treatment weighting was used to minimize confounding. Univariate logistic regression analyses were performed on the weighted sets using absent or delayed beta-blockers as the independent variable and each outcome as dependent variables in separate analyses. A secondary analysis was performed in patients prescribed preoperative beta-blockers. E-values were calculated for significant outcomes. RESULTS:All results were confounder adjusted. Among patients presenting for cardiac surgery, not receiving beta-blockers by POD 5 or at any time was not associated with the primary outcome in-hospital mortality, estimated odds ratio (OR; 99.5% confidence interval [CI]) of 1.6 (0.49-5.1), P = .28. Not receiving beta-blockers by POD 5 or at any time was associated with postoperative atrial fibrillation, estimated OR (99.5% CI) of 1.5 (1.1-2.1), P < .001, and pulmonary complications, estimated OR (99.5% CI) of 3.0 (1.8-5.2), P < .001. E-values were 2.4 for postoperative atrial fibrillation and 5.6 for pulmonary complications. Among patients presenting for cardiac surgery taking preoperative beta-blockers, not receiving beta-blockers by POD 5 or at any time was not associated with the primary outcome mortality, with estimated OR (99.5% CI) of 1.3 (0.43-4.1), P = .63. In this subset, not receiving beta-blockers by POD 5 or at any time was associated with increased adjusted ORs of postoperative atrial fibrillation (OR = 1.6; 99.5% CI, 1.1-2.4; P < .001) and postoperative pulmonary complications (OR = 2.8; 99.5% CI, 1.6-5.2; P < .001). Here, e-values were 2.7 for postoperative atrial fibrillation and 5.1 for pulmonary complications. For the sensitivity analyses for secondary outcomes, exposure and outcome periods overlap. Outcomes may have occurred before or after postoperative beta-blocker administration. CONCLUSIONS: Among patients who undergo cardiac surgery, not receiving postoperative beta-blockers within the first 5 days after cardiac surgery or at any time is not associated with in-hospital mortality and is associated with, but may not necessarily cause, postoperative atrial fibrillation and pulmonary complications.