Preclinical and clinical studies have sought to better understand the effect of anesthetic agents, both volatile and intravenous, and perioperative adjuvant medications on immune function. The immune system has evolved to incorporate both innate and adaptive components, which are delicately interwoven and essential for host defense from pathogens and malignancy. This review summarizes the complex and nuanced relationship that exists between each anesthetic agent or perioperative adjuvant medication studied and innate and adaptive immune function with resultant clinical implications. The most commonly used anesthetic agents were chosen for review including volatile agents (sevoflurane, isoflurane, desflurane, and halothane), intravenous agents (propofol, ketamine, etomidate, and dexmedetomidine), and perioperative adjuvant medications (benzodiazepines, opioids, nonsteroidal anti-inflammatory drugs [NSAIDs], and local anesthetic agents). Patients who undergo surgery experience varying combinations of the aforementioned anesthetic agents and adjuncts, depending on the type of surgery and their comorbidities. Each has unique effects on immunity, which may be more or less ideal depending on the clinical situation. Further study is needed to better understand the clinical effects of these relationships so that patient-specific strategies can be developed to improve surgical outcomes.

Background Telemedicine for preanesthesia evaluation can decrease access disparities by minimizing commuting, time off work, and lifestyle disruptions from frequent medical visits. We report our experience with the first 120 patients undergoing telemedicine preanesthesia evaluation at Moffitt Cancer Center. Methods This is a retrospective analysis of 120 patients seen via telemedicine for preanesthesia evaluation compared with an in-person cohort meeting telemedicine criteria had it been available. Telemedicine was conducted from our clinic to a patient’s remote location using video conferencing. Clinic criteria were revised to create a tier of eligible patients based on published guidelines and anesthesiologist consensus. Results Day-of-surgery cancellation rate was 1.67% in the telemedicine versus 0% in the in-person cohort. The two telemedicine group cancellations were unrelated to medical workup, and cancellation rate between the groups was not statistically significant ( P = .49). Median round trip distance and time saved by the telemedicine group was 80 miles [range 4; 1180] and 121 minutes [range 16; 1034]. Using the federal mileage rate, the median cost savings was $46 [range $2.30; 678.50] per patient. Patients were similar in gender and race in both groups ( P = .23 and .75, respectively), but the in-person cohort was older and had higher American Society of Anesthesiologists physical status classification ( P = .0003). Conclusions Telemedicine preanesthesia evaluation results in time, distance, and financial savings without increased day-of-surgery cancellations. This is useful in cancer patients who travel significant distances to specialty centers and have a high frequency of health care visits. American Society of Anesthesiologists Physical Status classification and age differences between cohorts indicate possible patient or provider selection bias. Randomized controlled trials will aid in further exploring this technology.

Background Sleep apnea, hypertension, atherosclerosis, and obesity are features of metabolic syndrome associated with decreased restorative sleep and increased pain. These traits are relevant for anesthesiology because they confer increased risks of a negative anesthetic outcome. This study tested the one-tailed hypothesis that rats bred for low intrinsic aerobic capacity have enhanced nociception and disordered sleep. Methods Rats were from a breeding strategy that selected for low aerobic capacity runners (LCR) and high aerobic capacity runners (HCR). Four different phenotypes were quantified. Rats (n=12) underwent von Frey sensory testing, thermal nociceptive testing (n=12), electrographic recordings of sleep and wakefulness (n=16), and thermal nociceptive testing before and for six weeks after a unilateral chronic neuropathy of the sciatic nerve (n=14). Results Paw withdrawal latency to a thermal nociceptive stimulus was significantly (P<0.01) less in LCR than HCR rats. There were significant differences in sleep. LCR rats spent significantly (P<0.01) more time awake (18%) and less time in non-rapid eye movement sleep (−19%) than HCR rats. Non-rapid eye movement sleep episodes were of shorter duration (−34%) in LCR than HCR rats. Rapid eye movement sleep of LCR rats was significantly more fragmented than Rapid eye movement sleep of HCR rats. LCR rats required two weeks longer than HCR rats to recover from peripheral neuropathy. Conclusions Rodents with low aerobic capacity exhibit features homologous to human metabolic syndrome. This rodent model offers a novel tool for characterizing the mechanisms through which low aerobic function and obesity might confer increased risks for anesthesia.

Purpose of ReviewFor patients with cancer, treatment may include combination therapy, including surgery and immunotherapy. Here, we review perioperative considerations for the patient prescribed immunotherapeutic agents. Recent Findings The perioperative period is a poignant moment in the journey of a patient with cancer, potentially deemed most influential compared to other moments in the care continuum. Several immunotherapeutic medications have been employed near the time of surgery to potentially increase effectiveness. Of the various drug classes, including immune checkpoint inhibitors, cytokines, toll-like receptor agonists, and oncolytic viruses, among others, several notable immunerelated adverse effects were noted. They range from minor effects to more serious ones, such as renal failure, myocarditis, and tumor growth. Summary Surgery and immunotherapy are often employed in combination for primary treatment and prevention of cancer recurrence. Careful review and consideration of the pharmacokinetics, pharmacodynamics, and toxicities of immunotherapy benefit the perioperative physician and their patients.

The surgical stress and inflammatory response and volatile anesthetic agents have been shown to promote tumor metastasis in animal and in-vitro studies. Regional neuraxial anesthesia protects against these effects by decreasing the surgical stress and inflammatory response and associated changes in immune function in animals. However, evidence of a similar effect in humans remains equivocal due to the high variability and retrospective nature of clinical studies and difficulty in directly comparing regional versus general anesthesia in humans. We propose a theoretical framework to address the question of regional anesthesia as protective against metastasis. This theoretical construct views the immune system, circulating tumor cells, micrometastases, and inflammatory mediators as distinct populations in a highly connected system. In ecological theory, highly connected populations demonstrate more resilience to local perturbations but are prone to system-wide shifts compared with their poorly connected counterparts. Neuraxial anesthesia transforms the otherwise system-wide perturbations of the surgical stress and inflammatory response and volatile anesthesia into a comparatively local perturbation to which the system is more resilient. We propose this framework for experimental and mathematical models to help determine the impact of anesthetic choice on recurrence and metastasis and create therapeutic strategies to improve cancer outcomes after surgery.