Anesthesiology

Recent Advances in Anesthesia

By | Uncategorized | No Comments

It is a formidable and near impossible task to discuss all pertinent advances in the field of anesthesia that have come to pass in the recent years, however it is interesting to look back and review a few of the changes that have reshaped our practice. Almost certainly there will be large omissions, particularly in subspecialties such as pediatrics and cardiac anesthesia; our focus will be on adult general anesthesia, from the perspective of practicing at a large academic institution.

New drug developments have always had the potential to alter the scope of our practice, but it is difficult to think of one that has had so much impact in recent years as the development and popularization of sugammadex. Instead of competitively reversing neuromuscular blockade by increasing acetylcholine levels as the acetylcholinesterase inhibitors do, sugammadex directly binds and inactivates the nondepolarizing neuromuscular blocker itself (most specifically rocuronium, but also vecuronium and pancuronium at a lower affinity; it has no action on succinylcholine or cisatracurium). Its action is dosage dependent, and its use is not limited by the number of twitches a patient has on nerve monitoring. Implications are vast and include a faster and more effective recovery from paralysis, which ensures improved post-operative respiratory mechanics and patient safety. Sugammadex also allows the anesthesiologist to keep the patient paralyzed for longer periods of time, optimizing surgical conditions during complex cases.  It is also effective at rescuing over-dosing of neuromuscular blocking drugs (whether unintentional or intentional, such as in rapid sequence inductions where succinylcholine is contraindicated). While Sugammadex must be used with caution in patients with renal disease, and may interact with oral contraceptives, its safety profile is overall reassuring.

In the realm of anesthesia equipment, one of the most notable advances has been transnasal humidified rapid-insufflation ventilator exchange (THRIVE), otherwise known by its trademark, Optiflow. Essentially comprised of a high flow oxygen source capable of delivering up to 60L/min of humidified, warmed oxygen, delivered by nasal cushion, the system provides a constant stream of oxygen with high enough flow to decrease anatomic dead space and provide PEEP, while partially washing out accumulating carbon dioxide. This concept of apneic oxygenation has recently been used in ENT procedures in paralyzed, apneic patients for procedures lasting 30-60 minutes without desaturation. Its duration is limited by carbon dioxide toxicity, and therefore patient selection is important to avoid complications such as the exacerbation of pulmonary hypertension. It has also become a useful tool for difficult airway management, providing better preoxygenation and a source of passive oxygen during airway management; however care must be taken in patients with airway obstruction such as large obstructive tumors, as barotrauma may develop.

Finally, there is a general shift away from narcotic-based general anesthetics to multimodal analgesia, and increasingly more regional and neuraxial techniques. Surgeries on extremities are being performed more and more under regional blocks, evidence for better outcomes has been forthcoming for neuraxial techniques for hip and knee replacements, and the American Pain Society recently released new guidelines advocating for the use of multimodal regimens including ketamine, lidocaine, non-steroidals, and physical modalities.

The field of anesthesia is constantly changing. In order to stay current and provide quality, effective perioperative care, anesthesia professionals should be able to adapt to new drugs, equipment and trends in anesthetic management.

Preoperative Smoking Cessation: Importance and Consequences

By | Uncategorized | No Comments

Millions of cigarette smokers undergo surgical procedures in the United States every day. The effects of smoking on the surgical patient have been well-studied, and those of tobacco abstinence equally so. Even after accounting for smoking related diseases such as COPD and heart disease, smoking itself is an independent risk factor for surgical complications. One meta-analysis found relative risks of 2.15 for wound-related complications in smokers compared to non-smokers, 1.73 for pulmonary complications, and 1.60 for admission to the ICU. It is estimated that smoking results in roughly $10 billion in annual postoperative costs in the United States.

Smoking is known to accelerate atherosclerosis by way of endothelial damage, oxidative injury, pro-thrombosis, and promoting an unfavorable lipid profile. In addition to increasing the risk of coronary and peripheral vascular disease, smoking also elevates heart rate, blood pressure, and myocardial contractility due to increased sympathetic tone. In those with preexisting CAD, nicotine can cause coronary vasoconstriction. Carboxyhemoglobin levels can exceed 10% in smokers, compromising oxygen delivery.  The cardiovascular benefits of smoking cessation include decreasing the risk of all-cause mortality in smokers with coronary disease by 1/3 after at least several months of abstinence. More immediate benefits include decreased carbon monoxide levels and a decreased sympathetic tone.

While some pulmonary manifestations of smoking are irreversible (COPD, malignancies), abstinence can improve cough and wheezing after several weeks. Mucus production may increase over the initial weeks of cessation, however mucociliary clearance seem to partially improve after one week. Smokers are at higher risk for perioperative respiratory failure, laryngospasm and other induction-related airway events, pneumonia, bronchospasm, and unanticipated ICU admission. These complications were significantly decreased after 8 weeks of abstinence in several observational studies, with full benefit after 12 weeks. However some complications such as laryngospasm may be decreased after only a few days, due to decreased sensitivity to upper airway stimulation by chemical irritants.

Wound infections and dehiscence have long been associated with smoking, as well as bone nonunion. The duration of abstinence necessary to reverse this is on the order of weeks, however more studies need to be conducted to better define this period.

Smoking cessation is overwhelmingly beneficial in terms of perioperative morbidity and mortality. The longer the abstinence, the more profound the effects, but even brief periods of cessation may decrease intra- and post-operative complications. Anesthesia providers are in a unique position to influence patients to stop smoking prior to their surgical procedures, and can be an important step in achieving long-term abstinence.

References

Nolan MBWarner DO. Perioperative tobacco use treatments: putting them into practice. BMJ 2017;358:j3340

Warner DO. Perioperative abstinence from cigarettes: physiologic and clinical consequences. Anesthesiology 2006;358:356-67.

The New Frontier of Value-Based Care

By | Uncategorized | No Comments

As models for healthcare reform continue to evolve, value-based care is rising as a viable option for ensuring cost-effective, but efficacious, care to patients. Anesthesia is at the forefront of this discussion. For a total surgery, anesthesia often drives cost upwards — in fact, studies report that about 6% of perioperative costs are attributed to anesthesia alone[1]. Moreover, anesthesia is central to the success of the surgery, and thus is a strong value driver for assessing outcomes. Anesthesiologists, Certified Registered Nurse Anesthetists (CRNAs), and anesthesia management companies will be wise to consider the implications of value-based care on the field of anesthesia.

The first major point of analysis for anesthesia professionals to consider is that value-based care will require a high level of standardized data. Anesthesiologists would likely be required to report several measures of quality and clinical practice improvement. Naturally, one of these categories would be comprised of an objective measure of patient outcomes. This data would include the patient’s state before, during, and after the surgery, with a particular emphasis on adverse events such as nausea, gastrointestinal events, or consciousness during surgery. Electronic Medical Records, which Xenon has written on prior to this article, could assist throughout this stringent reporting mechanism. In such a manner, hospitals and medical centers would be assigned a value that is an average of the physician and CRNA medical reports. This average would provide an aggregate, standardized measure of the practice’s value for anesthesiology, which is then utilized to dictate reimbursement in a value-based care model.

In addition, value-based care will necessitate an increase in team-based delivery. While the prior model for care depends on intervention, value-based care focuses on prevention as a means for smoothing costs across a patient population while also driving up outcomes. Anesthesiologists and CRNAs have a crucial role to play in this evolution. Instead of working in silos, anesthesia professionals must be willing to engage in disease-based teams — for example, an oncology team, or a heart disease team. When expert clinicians come together and follow a patient through the medical journey, it is more likely that the patient will receive the appropriate and timely care he/she needs[2]. Moreover, through this method, anesthesia professionals are more highly informed about the patient’s state, thus improving their assessment of how the patient’s care should be delivered. Clinical team models are essential to moving towards value-based care, and anesthesia professionals will prove to be invaluable to this initiative.

Along with specific data requirements and delivery reform, anesthesia professionals can support the implementation of value-based care initiatives by engaging in leadership at the administrative level. Streamlining is essential to maintaining the continuum of care required for a high-value operation. While there are many options for leadership in the medical community, anesthesiologists and CRNAs have the unique expertise to lead in this role, engaging with other medical personnel to ensure a successful surgery.

If executed correctly, value-based care can result in better outcomes for the patient, greater reimbursement to the hospital or healthcare center, and minimized risk across a population. Payers and patients alike will look favorably upon healthcare practices that have made a transparent commitment to increasing the value delivered to their patients. Furthermore, in the often risky and costly perioperative world, anesthesiologists and CRNAs are crucial leaders for promoting an outcomes-driven practice that places the patient at the center.

References

[1] https://www.ncbi.nlm.nih.gov/pubmed/8533904

[2] https://www.hbs.edu/faculty/Pages/item.aspx?num=50278

Global Discrepancies in Anesthesia

By | Uncategorized | No Comments

For many years, the healthcare systems of high-income countries have prioritized safe practices in both surgery and anesthesia. However, with the global burden of disease (GBD) continuously worsening for non-communicable diseases (NCDs), low- and middle-income countries (LICs and LMICs) are in great need of prioritized surgical and anesthetic services. For many of these countries, safe and adoptable practices are critical to improving health outcomes for leading causes of mortality, including cardiovascular disease, trauma, cancer, and obstetrics.

Every year, 32 million people are administered anesthesia without sufficient monitoring, while the poorest 33% of the world population receives only 3.5% of all surgical operations. In an effort to explain this disparity and ensuing crisis, multiple organizations, including the World Health Organization (WHO) and the Harvard Humanitarian Initiative (HHI) have surveyed and assessed the healthcare systems of LICs and LMICs across Africa, Southeast Asia, and Central and South America. The findings suggest that, in many rural areas, deficient infrastructure, a lack of human resources, and a shortage of essential instruments, equipment, and medicines are major contributors to the issue.[1]

The Lancet Commission on Global Surgery recently pointed to the lack of access to safe surgical and anesthetic services for 5 billion people around the world and the projected investment necessary to equalize the imbalance between high and low resource environments.[2] It referenced the World Federation of Societies of Anesthesiologists (WFSA), which consists of 135 member societies representing 150 countries. From 2015 to 2016, WFSA conducted a survey to capture an up-to-date, comprehensive snapshot of access to surgical and anesthetic care for 97.5% of the world’s population, which included non-physician anesthesia providers (NPAPs).  Today, only 50% of all countries meet the sufficient ratio of 5 anesthesiologists per 100,000 population. In fact, high income countries have nearly 95 times the density of anesthesiologists compared to low-income countries.[3] This imbalance and the projected need for 136,000 additional anesthesiologists necessitates novel approaches and models for care delivery, especially in low-income and rural areas. So where can we start?

First, it is necessary to recognize that the availabilities of both human resources and infrastructure vary across low-income and rural regions, and together, they should dictate which model is most appropriate for improved anesthesia care delivery.

Second, specialist anesthesiologists from high-, middle-, and low-income countries must lead the specialty towards adopting a broader, global perspective. Safe anesthesia administration begins with education, and the number and quality of academic training programs across countries, especially in low-income and rural areas, needs to substantially increase. It is equally imperative for this growth to be coupled with additional anesthesia educators and resources. While the Ministries of Health in many LICs and LMICs have already recognized the need for continued development of NPAP training programs, anesthesiologists should assist governments in developing country-specific roadmaps, consisting of a standardized curriculum and training duration, an accreditation process, and clear delineation of scope of practice across provider levels.

Finally, anesthesiologists and organizations in LICs and LMICs can help providers in remote or rural areas by both establishing support networks and offering opportunities for continued medical education. ‘Quick-fix’ solutions that are often proposed by non-anesthesiologists are not the answer. An example is a 5-day course teaching non-physician healthcare workers how to administer ketamine for surgery. This is not safe, jeopardizes the health of many patients, and endangers the continuation of formal training programs and care delivery standards.

Despite the major challenges that anesthesia faces in low-income and rural areas, the silver lining lies in the fact that we now have a more complete, global picture that highlights the discrepancies in the access to and administration of care. The global anesthesia community now has the opportunity to work cohesively to provide safe, affordable, and accessible care for 5 billion people across the world.

References

[1] Martin, J., Tau, G., Cherian, M. N., de Dios, J. V., Mills, D., Fitzpatrick, J., … & Cheng, D. (2015). Survey of the capacity for essential surgery and anaesthesia services in Papua New Guinea. BMJ open, 5(12), e009841.

[2] Enright, A., & Newton, M. (2017). Human Resources in Anesthesia: The Road to 2030.

[3] Kempthorne, P., Morriss, W. W., Mellin-Olsen, J., & Gore-Booth, J. (2017). The WFSA global anesthesia workforce survey. Anesthesia & Analgesia, 125(3), 981-990.

Choosing a Hospital vs. a Surgery Center

By | Uncategorized | No Comments

In today’s healthcare environment, surgical procedures may be performed in a variety of different settings. Choosing between a surgery center and a hospital is a big decision for patients, and many factors come into play when determining which option is best. Surgery centers, also known as ambulatory surgery centers (ASCs), are licensed, freestanding outpatient facilities. These centers are often physician-owned, may specialize in certain procedure and are typically smaller than hospitals. Surgery centers have become increasingly prevalent, and more surgeries are being performed at such facilities, particularly because of advances in anesthesia that have increased the provision of ambulatory anesthesia services. Clinical advances in technology, financial incentives, and a greater demand for lower-cost and higher quality care have also contributed to the rise in surgery centers. The volume, age, and complexity of the outpatient surgical population has grown, and more patients are now facing the choice between different surgical settings [1].

When deciding between a hospital or a surgery center, one must first determine that the patient’s case is appropriate for an ambulatory surgery setting. Unlike hospitals, surgery centers do not have various support departments such as MRI suites and ICUs, and there have been concerns in regards to their ability to handle major problems during surgery. Hospitals have more resources to manage complications, and patients are often transferred from a surgery center to the nearest hospital facility should complications arise during a procedure. Patient selection is essential to ensure safety in a surgery center, as not all patients are candidates for outpatient surgery. The procedure, personnel involved, patient’s medical status, and surgical setting all affect the patient selection process. Anesthesia also plays a critical role, since the requirement of anesthesia and the type of anesthesia provider, be it an anesthesiologist, a CRNA, or a surgeon and nurse, are key factors in patient selection [2]. A study on risk factors for major morbidity and mortality from outpatient surgery revealed that patients with cerebrovascular disease, obesity, cardiac disease, or prolonged surgery face greater risk, making a hospital generally more appropriate for such cases [1]. Frail older adults may have stronger reactions to anesthesia and may be more likely to experience surgical complications and take longer to heal, therefore they should consider surgery at a hospital setting as well [3].

While hospitals are often better suited for higher risk surgical cases, research has shown that surgery centers have many advantages over hospital facilities. Due to lower overhead, fixed costs, and the inability of patients to stay overnight, surgery centers often cost 45-60% less than a hospital setting. One study revealed that surgery center performance generally exceeds that of a hospital-based facility and that the quality of surgery was superior if not equal to a hospital [4]. Surgery centers are able to exercise increased control over procedure scheduling, resulting in reduced procedure delay and rescheduling, and they have been shown to perform procedures more efficiently than a hospital-based facility. Additionally, while surgical site infection rates are low in both surgical settings, surgery centers experience lower rates on average than hospitals [5].

Choosing a facility ultimately depends on each individual circumstance. There are benefits and drawbacks to both hospitals and surgery centers, and studies have shown similar positive patient experiences at both types of facilities [4]. Not all patients are suitable for outpatient procedures, and hospitals are more appropriate for complicated, risky cases as well as procedures that require greater observation and recovery times. However, for patients who are eligible for outpatient surgery, surgery centers offer a higher quality, lower-cost alternative to hospitals.

References

[1] http://anesthesiology.pubs.asahq.org/article.aspx?articleid=1918045

[2] http://www.sciencedirect.com/science/article/pii/S0094129813000291?via%3Dihub

[3] https://www.consumerreports.org/surgery/get-the-best-care-at-an-ambulatory-surgery-center/

[4] https://www.sciencedirect.com/science/article/pii/S0194599809014788

[5] https://www.beckershospitalreview.com/quality/ssi-rates-hospitals-vs-ascs-2010.html

[6] https://www.healthaffairs.org/doi/abs/10.1377/hlthaff.2013.1281

[7] https://www.advisory.com/daily-briefing/2014/09/16/are-surgery-clinics-less-safe-than-hospitals