The number of outpatient surgical procedures performed outside of hospital settings has increased dramatically over the past three decades. A significant portion of this growth has been in the office-based setting, with office-based surgical procedures making up an estimated 1/6th of all outpatient procedures in 2005. This growth has been driven by economic and reimbursement factors along with patient and provider convenience and comfort. Ultimately, it has been the growing understanding and acceptance of office-based anesthesia (OBA) that has enabled surgeons to move increasing surgical volume to their offices.
With healthcare reform likely to change how services are paid for, the trend of hospital acquisition of ambulatory surgical centers and private physician practices seems poised to continue. Despite this, accountable care organizations or other hospital-based payment groups are likely to be interested in the same economic efficiencies as the private practitioner. Thus, it seems reasonable to expect that the number of office-based procedures will only increase.
Patient safety remains the paramount concern in the office-based setting, but definitive statements on the subject are difficult to make. The quality of data on the subject is limited by the relative youth and ongoing evolution of the subspecialty, lack of homogeneity across OBA practices and settings, and lack of consistent reporting of complications. While drawing lessons from retrospective analysis of safety, an anesthesiologist entering the field of OBA must primarily look for approaches to maximize future patient outcomes. This chapter does not seek to discuss specific pharmacological approaches to OBA, which are essentially similar to those presented elsewhere in this book. Instead, it will focus on some of the unique concerns and pitfalls encountered by the anesthesiologist in the office-based setting.
Prior to administering any anesthetic in an office-based setting, the anesthesiologist must ensure a safe and functional operating environment. This responsibility extends well beyond the anesthesia machine itself, and covers elements that might be taken for granted in a hospital setting.
Perhaps the best starting point when evaluating a potential site for OBA is to inquire about the office’s accreditation status. Accreditation requirements for office-based surgery (OBS) practices vary by state, with some states having no specific requirements. Other states, meanwhile, have extensive guidelines and regulations for OBS. The Federation of State Medical Boards currently maintains a state-by-state listing.[3,4] States without current regulations may create these in the future, so up-to-date information should be verified.
OBS practice accreditation can be obtained through one of three organizations: The Joint Commission (TJC), the Accreditation Association for Ambulatory Healthcare (AAAHC), and the American Association for Accreditation of Ambulatory Surgery Facilities (AAAASF). The basic requirements for each of these groups are similar. With the exception of the AAAHC, which has the ability to accredit OBA practices independently, the responsibility for obtaining accreditation lies with the owner of the OBS practice.
For the purposes of accreditation and state regulatory compliance, OBS practices are generally divided into three levels. Two classification schemes exist, one ranging from Level I to III and the other from Class A to C. The Level system focuses somewhat more on surgical complexity, while the Class system is defined by level or technique of anesthesia. Ultimately, both systems are defined by the likelihood of unconsciousness and anesthetic complications. Level I/Class A allows for local or distal nerve blocks with only mild oral anxiolysis. Level II/Class B allows for mild to moderate parenteral sedation and analgesia. Level III/Class C allows for deep sedation, general anesthesia, and regional or neuraxial blocks. Understanding the level at which a potential OBA site is accredited is important, as this determines which anesthetic techniques are allowed. Confusingly, some state boards deviate from these systems. Texas, for example, uses Levels I–IV, with only IV allowing general anesthesia.
For office-based anesthesia practices that are not accredited, several professional organizations have provided a basic set of guidelines that serve as a minimum benchmark for all providers. Examples from the American Society of Anesthesiologists (ASA) Guidelines for Office-Based Anesthesia include the following:
The presence of a medical director responsible for verifying adequate training and credentialing of all anesthesia providers and staff.
Ongoing quality improvement, continuing education, and risk management activities.
Appropriate patient selection based on comorbidities and surgical complexity.
Adherence to all basic anesthesia and ambulatory anesthesia guidelines as provided by the ASA, including for standard monitoring equipment.
Appropriate space and staffing for post-anesthesia recovery evaluation.
Facilities with adequate emergency equipment and backup power supply.
Written plans for medical and non-medical emergencies including specific patient transport and transfer protocols.
The immediate presence of the anesthesiologist during the entire intraoperative period.
While OBS practice accreditation suggests compliance with basic standards, the ASA rightly cautions that the office setting may lack rigorous mechanisms and staff for maintaining adherence between accreditation cycles. Any anesthesiologist starting or joining an OBA practice should independently verify a number of factors at each OBA site. The following are examples of potential problem areas, but should not be taken as an exhaustive list of requirements. For the latter, the various accrediting bodies offer detailed handbooks or manuals available outside of the formal accreditation process. The ASA offers an OBA handbook with in depth discussion of these and other issues.
The anesthesia machine and monitors are likely owned by the surgeon who owns the OBS practice but may have little anesthesia experience. It is the responsibility of the OBA provider to verify that the equipment meets current standards and remains factory-supported. Maintenance and calibration need to be completed in accordance with manufacturer recommendations. The American Society of Anesthesiologists maintains guidelines for determining anesthesia machine obsolescence and recommends against obsolete machines being used in any setting. Mobile anesthesia machines that travel with the anesthesiologist may make it easier to ensure equipment maintenance across OBS practices, but facility-specific equipment such as defibrillators should still be inspected.
Medical gas supply should be verified if coming from outside the immediate operating room (OR). Protocols for checking and replenishing gas supplies should be in place. A redundant backup system is a necessity. Waste gas scavenging is important for both patient and staff safety, and purpose-built office operating rooms may include adequate exterior venting of the scavenging system. This should be examined, however, especially in converted office space. While physician office space should meet minimum occupational health guidelines for ventilation and air exchange, these may be inadequate for an OR environment that includes electrocautery smoke and leaked anesthetic agents.
Fire safety must be considered in any OBS setting. OR fires can have devastating effects, and prevention requires awareness and participation on the part of all OR staff. Anesthetized patients or those under regional or neuraxial block present very different challenges from regular medical office patients in the event of an evacuation. All staff should be aware of OR-specific fire response plans, including evacuation of intubated patients, and these should be practiced in an organized fashion.
Electrical systems should be evaluated both for electroshock prevention and adequate backup power capability. Hospital construction regulations no longer require isolated circuits in ORs, and these would not be expected in an office setting. Ground fault circuit interrupter (GFCI)-type outlets offer the next best level of protection against accidental electroshock from short-circuited equipment and should be tested regularly. Backup power should be redundant and must be available in uninterrupted fashion to all life support, anesthesia machine, monitor, and suction pump outlets.
Anesthetic drugs, controlled or otherwise, must be securely stored in the absence of a central pharmacy. Whether controlled drugs are procured via the DEA license of the surgeon or of the anesthesiologist, it is the responsibility of the OBA provider to adequately document daily usage and waste. A protocol for reordering medication and monitoring usage rates to avoid medication expiration should be established.
Infection control remains an important concern in the OBS setting. In a cost-driven environment, there may be a temptation to find efficiency by splitting multi-dose vials between patients and minimizing the number of syringes and needles opened per case. Detailed guidelines are available for minimizing the risk of patient to patient transmission of infectious diseases, and the anesthesiologist should follow these carefully. As medications may be administered by support staff in the pre-op or recovery room settings, a general infection control policy for all staff should be available and enforced.
Finally, emergency equipment, supplies, and medications should be easily available and fully functional. This includes a code cart, defibrillator, difficult airway supplies, and emergency medications. Required medications include ACLS drugs, the availability of dantrolene if any malignant hyperthermia-triggering agents are used or could potentially be used in the office, and the intralipid solution for local anesthetic toxicity management. Naloxone and flumazenil should also be available if opioids or benzodiazepines, respectively, are being administered. The ASA OBA manual includes in-depth tables of recommended emergency drugs. Resuscitative equipment and medications will generally be provided by the surgical office, but the anesthesiologist’s responsibilities include verifying their availability and functionality prior to any clinical care. Furthermore, a written plan for the emergency transfer of patients to a hospital setting must be verified. Easy access to ambulance and pre-hospital emergency care should be planned for and available. These plans should be present regardless of the surgeon’s admitting privileges.