Today, while talking to a dear friend, and one of my oldest patients, he asked my opinion regarding the sudden, unexpected death of comedian Joan Rivers. I told him, it appears, from the very limited information that something went very wrong during that procedure to make her heart stop beating (known as a cardiac arrest). While the heart can stop beating at anytime, resuscitation often restarts it, and allows the body to keep living. If the brain is deprived of oxygen for several minutes, it experiences severe damage that is incompatible with life, which seems to be the case with Joan.
According to the media reports, she experienced a cardiac arrest, meaning her heart stopped, while undergoing a routine endoscopy (an examination of her vocal chords), a diagnostic procedure to determine the cause of her raspy voice. While the coroner’s initial findings were inclusive, the actual cause of her cardiac arrest may never be determined. The NY Public Health Department is now conducting an investigation and we’ll have to wait for their findings to see if an error did occur. I found a news report that indicated her room was equipped with advanced life support capabilities.
Anesthesia errors is a major cause of medical errors. Our conversation prompted me to research and share what I found with you, with the hope that you will know what to do if you or a loved one needs to have outpatient surgery.
Our conversation prompted me to research general anesthesia errors and cardiac arrest in particular, to share this important information with you.
During my research, a frightening incident that I’d almost forgotten, unexpectedly rushed into my awareness, while reading an article on errors occurring in outpatient settings. An anesthesia error that almost ended my life.
Twenty-five years ago, I almost died while having a routine dental procedure (two root canals), because I wasn’t properly monitored. The dentist gave me Nitrous oxide, an anesthetic administered by mask, and left the room, to check on another patient. A patient receiving anesthesia, should never be left unattended. A few minutes later, while feeling quite relaxed and no pain (Nitrous oxide is known as laughing gas), I began to feel my heart rate slowing down. Suddenly I could not move. Immediately I knew I was receiving too much gas, and I was dying. I didn’t want to die. For some reason, I wasn’t afraid to die, but knew I had just a few seconds to find the strength needed to raise my paralyzed hand and get the mask off my face. Somehow, by sheer force of will, I concentrated all of my attention on my hand and forced it to move. It felt like I was lifting a ton, and with all of my might, a surge of energy came through my hand and I managed to raise my right hand and snatched the mask off my face.
I was so grateful, there are no words to adequately express, how relieved I was to remain in my body. It was a very traumatic experience, and it took me years to return to a dentist (not that one) for care. Every time I have a dental appointment, that memory returns. Fortunately, dentists are required to have procedures have changed today, and most dentists don’t use the gas anymore—I haven’t received any more laughing gas. And trust me, I wouldn’t take it, if offered.
The Explosion of Outpatient Surgery
When I was in medical school, outpatient surgery was unheard of. Every surgical procedure occurred in the hospital. Today more and more procedures taking place in nonhospital settings, but they are not as regulated and potentially more dangerous than hospital settings are. An Institute of Medicine report notes, little if any research has focused on errors or adverse events occurring outside of hospital settings, for example, in ambulatory care clinics, surgicenters, office practices, home health, or care administered by patients, their family, and friends at home.
According to a report commissioned by the Institute of Medicine, in this uncertain and rapidly shifting policy environment, there is no consensus about the appropriate measures that should be taken to ensure patient safety in the outpatient setting. Guidelines exist in some cases, but oversight and enforcement are inadequate. Recently developed procedures, equipment, and drugs have made outpatient and office surgery more accessible. Although no regulations ever prohibited physicians from performing surgery in their offices, until recently the technology required for doing so did not exist. Minimally invasive procedures using laparoscopes, arthroscopes, and cystoscopes have significantly decreased post operative recovery. In general, procedures that can be performed in an outpatient setting are those having low rates of postoperative complications that require intensive physician or nurse management. Today, 65 percent of all surgical procedures do not involve a hospital stay.
Since 1984, the growth in outpatient surgery has been explosive, from an estimated 400,000 surgeries in 1984 to 8.3 million in 2000. Ten to twenty percent of all elective surgeries will be done in an estimated 41,000 office-based surgical facilities this year. As technology improves, we can expect outpatient procedures — and morbidity and mortality due to errors in the outpatient setting — to increase as well.
One reason for this sharp increase in office-based care is the lower costs of surgical procedures done outside hospitals — typically 60-75 percent lower than for comparable inpatient procedures. Medicare and some health maintenance organizations (HMOs) are aware of the lower costs of outpatient surgery and have reduced reimbursement fees when outpatient procedures are performed in hospitals or even in ambulatory surgery centers (defined as facilities having at least two operating rooms) rather than in physician offices, to encourage procedures to be performed in the lowest-cost setting. In addition, cosmetic surgical procedures (which are typically not covered by insurance) performed in the office reduce the cost to the patient (since there is no facilities fee) and provide an attractive direct-payment income stream to physicians.
Only a few studies have documented the types of errors that may occur in the outpatient setting; these studies have focused on anesthesia administration or lipoplasty. A study of ninety-five adverse sedation events in pediatrics between 1969 and 1996 found that the venue (hospital versus outpatient) was not associated with the incidence of respiratory events but that adverse outcomes occurred much more frequently in nonhospital settings. For example, death or permanent neurologic injury occurred in fewer than half (37 percent) of adverse sedation events in the hospital, whereas in the outpatient setting the rate was 93 percent. Inadequate resuscitation contributed to poor outcomes twenty-six times more often in nonhospital facilities than in hospital settings.
Studies demonstrate, anesthesia appears to pose a particular risk in the outpatient setting. When persons without adequate experience or equipment administer anesthesia, there can be devastating consequences that are difficult to correct in an office setting. Patients may suffer from malignant hyperthermia, a rare reaction to anesthesia drugs that causes the body to overheat. It can be corrected with dantrolene, an expensive drug that many office practices simply do not stock. Young children are easily susceptible to becoming over-sedated during procedures. Children may stop breathing while sedated and can die if not properly monitored. Office-based practices typically do not measure the oxygen levels of their patients or have crash carts, cabinets on wheels that contain resuscitation and emergency therapeutic medication that are standard equipment in the hospital. Despite clear recommendations from the American Society of Anesthesiologists (ASA) on the use of pulse oximetry (which measures blood levels of oxygen), it does not appear to be used consistently in outpatient settings.
New York Regulation Legislation Weakened
In February 1999 the New York State Senate Committee on Investigations, Taxation, and Government Operations convened a committee to study problems of office-based surgery. The investigation was conducted as the New York State Public Health Council simultaneously drafted clinical guidelines for office-based surgery. Unfortunately, the guidelines, which were issued in June 1999, are nonbinding, so there is no incentive for physicians to comply with them and no way for patients or state officials to know whether or not physicians are following them. The council stipulated that all physicians in New York receive a copy of the guidelines and that they be posted on a Web site. The committee recommended that the legislature empower the New York State Department of Health to issue regulations on office-based surgery, just as it already issues regulations for hospitals and ambulatory surgical centers. The regulations would have ensured that practitioners were credentialed in the fields in which they were doing procedures, established restrictions on administering anesthesia, and created minimum levels of equipment and maintenance schedules. State inspections of facilities would be conducted to ensure compliance. Had this legislation passed, it would likely have helped to improve the safety of office-based surgery in New York.
However, using the legislature as the means for creating regulations was not effective in New York. The lobbying of special-interest groups, especially the Medical Society of New York and the New York State Association of Nurse Anesthetists, and partisan interests of legislators killed support for the legislation. In 1999 a weaker measure, which calls for the reporting of complications and deaths from office-based procedures, was passed. New York State’s health commissioner is responsible for compiling outcomes data based on reported events to determine whether errors occurred, so that the legislature can evaluate whether additional legislation is needed. Still, the end result of New York’s effort fell short of its original goal and casts doubt on whether such attempts in other states can succeed.
Anesthesia Error Statistics
The American Society of Anesthesiologists examines closed medical malpractice claims in order to investigate and potentially improve standards for anesthesiology. Data shows that respiratory issues are one of the most common causes of serious injury and death. Of the cases examined, 45 percent consisted of respiratory issues that resulted in brain damage and death of patients.
A Columbia University study examined 2,211 anesthesia-related deaths that occurred over the course of six years. On average, roughly 300 anesthesia-related deaths occurred each year. The data was analyzed to determine the most common causes of anesthesia-related deaths.
A Columbia University anesthesia errors study revealed that, of the deaths:
• 46.6 percent were caused by anesthetics overdose
• 42.5 percent were related to the adverse effects of anesthetics during therapeutic use
• 3.6 percent occurred during pregnancy or labor
• The remaining 7.3 percent were due to other complications
Anesthesia Complications Lead to Patient Injuries
Anesthetics are administered about 40 million times each year. Anesthesiologists participate 90 percent of the time. Anesthesia is administered for most surgeries today, whether the procedure is performed in a hospital, an ambulatory surgery center or a doctor’s office. Anesthesiologists must administer medication safely and monitor a patient’s vital signs and level of consciousness during surgery. Any mistake in dosage or type of anesthesia can have serious consequences. General anesthesia is usually safe for healthy people. However, people who abuse alcohol or drugs, smoke, have allergies or who have a history of heart, lung or kidney problems may face a higher risk of problems with general anesthesia.
Anesthesiologists and other surgical or medical staff members have a duty to avoid mistakes by not rushing or cutting corners while patients are under the influence of anesthesia in preoperative, surgical, recovery and post-operative settings. Errors can occur while a patient is under anesthesia, which is normally administered or supervised by an anesthesiologist( a medical doctor whose specialty is medically inducing sedation or sleep using a variety of medications to prevent a patient from feeling pain while in surgery). The anesthesiologist’s job is to monitor a patient’s heart rate, blood pressure, blood circulation, breathing, and body temperature before, during and after a procedure surgery preventing anesthesia complications and anesthesia error.
According to statistics hundreds of people are the victims of anesthesia errors every day. More than 200 individuals daily, are victims of Anesthesia awareness. Anesthesia awareness occurs during the administration of anesthesia when a patient is administered a miscalculated dosage of medications that are supposed to keep them unconscious and free from feeling pain. As a result of the paralyzing agents of the anesthesia, the patient remains in a paralyzed state unable to move or communicate with the doctors operating on them, while they endure the pain of the entire surgery.
Regardless of the patient’s health, general anesthesia can cause these complications:
• Heart attack
• Lung infection
• Vocal cord injury
• Trauma to the teeth or tongue
• Temporary mental confusion
• Psychological trauma from waking during surgery.
Spinal and epidural anesthesia, which is administered by shots in or around the spine, can cause these complications:
• Infection in the spine (meningitis or abscess)
• Nerve damage
• Allergic reaction
• Bleeding around the spinal column (hematoma)
• Difficulty urinating
• Drop in blood pressure
• Severe headache.
Cardiac arrest attributable to anesthesia occurs at the rate of between 0.5 and 1 case per 10 000 cases, tends to have a different profile to that of cardiac arrest occurring elsewhere, and has an in-hospital mortality of 20%. However, as individual practitioners encounter cardiac arrest rarely, the rapidity with which the diagnosis is made and the consistency of appropriate management varies considerably.
Human Error, Mechanical Error in Anesthesia Injuries
Due to the high number of human errors made by anesthesiologists and anesthesia technicians when using anesthesia machines, the danger of anesthesia machine failure or defects poses a significant risk to patients. Studies investigating the frequency and causes of anesthesia machine error and anesthesia machine failure have found that the most common manufacturer defects found in anesthesia machines involve faulty tubes and hoses leaking intoxicating gases, and disrupting the flow of oxygen and other medications patients receive. Additionally electrical and computer errors have been reported, at times compromising automated calculations and other information that insure patient safety.
Many times anesthesia machine failure is the result of human error. Common errors made by anesthesiologists, and anesthesia technicians working in hospitals and surgical centers, include the failure to regularly train and familiarize themselves with anesthesia machines and equipment, failure to perform routine maintenance on all systems involved in administering anesthesia, the failure to properly install equipment, and incorrectly monitoring, operating, and setting up the machine.
The results of anesthesiologist mistakes and anesthesiologist errors can be devastating, often resulting in permanent injury, brain dysfunction, paralysis, blindness, sensory losses, and in the worst cases wrongful death. The most common injuries and occurrences of anesthesia malpractice and anesthesia error include but are not limited too;
A wide-ranging analysis of major errors and equipment failures in anesthesia management that was published in the Journal Anesthesiology found that most anesthesia errors are human errors.
Human anesthesia error most often concerns drug administration, anesthesia machine operation, airway management, breathing circuit / ventilation, fluid and electrolyte management, use of IV apparatus and monitoring device(s).
Ways in which medical staff can contribute to critical anesthesia events include:
• Failure to check / monitor
• Inattention or carelessness
• Haste encouraged by situation
• Unfamiliarity with equipment or device
• Unfamiliarity with drug
• Visual restriction
• Inadequate experience
• Inadequate familiarity with anesthesia activities
• Lack of familiarity with surgical procedure
• Lack of sleep / fatigue
• Failure to follow routine
• Failure to follow institutional practice
• Inadequate supervision.
Errors Made by Anesthesiologists
• Anesthesia awareness resulting in nervous damage
• Failure to monitor a patients consciousness
• Loss of sensory ability
• Wrongful death
• Oxygen deprivation
• Faulty or broken surgical table, resulting in patient falling or sustaining injuries while under anesthesia
• Anesthesia dosage error
• Use of improperly labeled medication
• Failure to record a patients medical history
• Failure to review patients medical history
• Anesthesiologists failure to review patients allergy chart
• Overdosing a patient with anesthesia medications
• Failure to monitor patients vital signs
• Failure to give a patient pre-operative instructions about not eating before surgery
• Faulty monitors and faulty alarms
• Shutting off pulse oximeter alarm
• Use of expired medication
• Unsterile equipment
• Prolonged sedation
• Failure to intubate resulting in oxygen deprivation
• Negligent intubation resulting in the intubation tube being placed into the patients stomach
• Brain damage
• Loss of neurological and sensory function
• Spinal cord injuries
• Trachea injuries as a result of negligent intubation
Mechanical failure can also lead to anesthesia errors, injuries and deaths, including problems with equipment such as:
• Breathing circuits
• Monitoring devices
• Anesthesia machines
• Airway devices
Outpatient Anesthesia Errors
Lately there has been an increasingly high number of anesthesia malpractice incidents occurring at ambulatory care surgical centers. Unfortunately many ambulatory surgery centers do not meet federal safety standards which have lead to serious and catastrophic consequences for patients. The following list includes but is not limited to common errors occurring at ambulatory care surgical centers resulting in anesthesia injuries to patients and medical malpractice including but not limited too;
• using medical supplies and medications with expired expiration dates,
• administration of the wrong drug,
• failure to monitor errors,
• failure to documenting allergies,
• confusion or mix up involving ophthalmology products of different pharmacological categories,
• differentiating lookalike products,
• operating on the wrong body part or wrong patient,
• surgical site infections,
• failure to prophylactically deliver antibiotics.
Sadly, the major excuse for anesthesia error and anesthesia malpractice is negligence on the part of the anesthesiologists, operating physicians and other medical technicians when caring for their patients. When a preventable anesthesia error or complication arises as the result of medical negligence, the operating doctor, anesthesiologist, medical facility, and hospital may be liable for damages sustained by you or a loved one.
The fast-paced environment of an operating room does not excuse medical professionals, technicians or other staff members who do not know or do not follow established procedures, ignore patients, misread monitors or misinterpret symptoms. Such errors may constitute medical negligence or medical malpractice if a patient is harmed.
How to Prepare for Outpatient Surgery
Surgery does not always require an overnight stay in the hospital. This type of surgery – often called same-day, outpatient, ambulatory or office-based – is becoming more common and can take place at an outpatient facility (connected to a hospital or at a separate surgical center) or in a physician’s office.
Nearly two-thirds of all operations are performed in outpatient facilities, according to the Centers for Disease Control and Prevention. Outpatient surgery provides patients with the convenience of recovering at home, and can cost less.
Most outpatient surgeries can take anywhere between a few minutes to a few hours but are not medical emergencies. Typical outpatient surgery ranges from simple mole removal to hernia repair to knee-replacement.
Although outpatient surgeries may not be medical emergencies, they still require some form of anesthesia or pain medication. The same anesthetic techniques used in hospitals may be used for outpatient surgery, ranging from local anesthesia to numb a small area of the body to general anesthesia, which results in total loss of consciousness and pain sensation. The surgery will most likely require you to prepare in the same way that you would for hospital-based surgery.
The American Society of Anesthesiologists recommends:
Before you have outpatient surgery, take the following precautions to ensure the safest and most successful result possible:
• Check qualifications – Be sure the physician leading your care is certified to perform the procedure by asking about the doctor’s qualifications and experience. Those who are qualified have special training and passed exams given by a national board of surgeons. Also ask your surgeon how much experience they have with the procedure, and their record of successes and complications with this surgery. Also, ask about malpractice law suits.
Be sure the nurses and other clinical staff who will support the surgeon are also experienced with the procedure and have the appropriate certifications. The outpatient surgery center should be licensed and accredited as well.
• Find out who’s providing and monitoring the anesthesia – Alleviating pain is a key part of surgery. Be sure a physician anesthesiologist is leading your anesthesia care.
• Be sure emergency procedures are in place – While complications are rare, they do occur. Prior to surgery, ensure that the surgery site has emergency medications, equipment and procedures in place to safely care for you if an emergency occurs. This is especially important because, unlike hospitals, an office-based or same-day surgery site may not have an emergency facility nearby.
On the day of the surgery:
• Plan for recovery time – When your surgery is completed, you will be taken to a recovery room where you should be closely monitored by a physician anesthesiologist or other physician. If you do not feel well or are in a lot of pain, tell your physician anesthesiologist. Once you have recovered from the anesthesia and are ready for discharge, you will be allowed to go home. Keep in mind that the decision to send you home will depend on your medical condition, type and length of surgery.
• Bring a friend or family member – Because your coordination and reflexes may be temporarily impaired, you must have a responsible adult with you to drive you home. It can take 24 hours to regain your coordination and reflexes, so it’s important to have a friend or family member stay with you for that time.
Your physician will give you specific instructions on how to prepare the night before and day of your surgery. By being prepared before surgery, you can increase your chances of a safe and successful experience. For more information on preparing for surgery, visit Preparing for Surgery.
The Agency for Health Care Research and Quality Recommends:
If you are having surgery, make sure that you, your doctor, and your surgeon all agree on exactly what will be done.
Having surgery at the wrong site (for example, operating on the left knee instead of the right) is rare. But even once is too often. The good news is that wrong-site surgery is 100 percent preventable. Surgeons are expected to sign their initials directly on the site to be operated on before the surgery.
If you have a choice, choose a hospital where many patients have had the procedure or surgery you need.
Research shows that patients tend to have better results when they are treated in hospitals that have a great deal of experience with their condition.
Speak up if you have questions or concerns.
You have a right to question anyone who is involved with your care.
Make sure that someone, such as your primary care doctor, coordinates your care.
This is especially important if you have many health problems or are in the hospital.
Make sure that all your doctors have your important health information.
Do not assume that everyone has all the information they need.
Ask a family member or friend to go to appointments with you.
Even if you do not need help now, you might need it later.
Know that “more” is not always better.
It is a good idea to find out why a test or treatment is needed and how it can help you. You could be better off without it.
If you have a test, do not assume that no news is good news.
Ask how and when you will get the results.
Learn about your condition and treatments by asking your doctor and nurse and by using other reliable sources.
For example, treatment options based on the latest scientific evidence are available from the Effective Health Care Web site. Ask your doctor if your treatment is based on the latest evidence.
http://www.aaahc.org (The Accreditation Association for Ambulatory Health Care)
http://www.cdc.gov/nchs/data/nhsr/nhsr011.pdf (Centers for Disease Control: Ambulatory Surgery in the US, 2006)
http://www.aaaasf.org/aboutus.html (American Association for Accreditation of Ambulatory Surgery Facilities)
http://www.sambahq.org/ (Society for Ambulatory Surgical Anesthesia)
http://www.asahq.org/sitecore/content/WhenSecondsCount/Patients-Home/Preparing-for-Surgery/Types-of-Surgery/Outpatient-Surgery.aspx (American Society for Anesthesiologists)
http://www.ahrq.gov/patients-consumers/care-planning/errors/20tips/index.html (American Healthcare Research & Quality)
Gaba, David. “Human error in anesthetic mishaps.”International Anesthesiology Clinics. 27.3 (1989): 137-147. Print.
Kazanjian, Paul E. “Avoiding Common Anesthesia Errors.”Anesthesiology. 108.5 (2008): 968. Print. http://journals.lww.com/anesthesiology/Fulltext/2008/05000/Avoiding_Common_Anesthesia_Errors.33.asp&xgt;.
Langelaar, Stephanie. “The Nature of Complexity; Human Factors and Human Error in Anesthesia.”California Association of Nurse Anesthetists. Samuel Merritt University. Web. 20 Sep 2013.
http://www.canainc.org/conference/2010/7. Stephanie Langelaar_The Nature of Complexity.pdf.
L.T. Kohn, J.M. Corr gan, and M.S. Donaldson, eds., To Err Is Human: Building a Safer Health System (Washington: National Academy Press, 2000), 25.
S.J. Lazarov, “Office-Based Surgery and Anesthesia: Where Are We Now?” World Journal of Urology 16, no. 6 (1998): 384-385.
Society for Ambulatory Anesthesia, “Patient Information,” http://www.sambahq.org/patient-info.html (30 November 2001, no longer available).
Lazarov, “Office-Based Surgery,” 384; and C. Luz, “JCAHO Offers Accreditation for Office-Based Surgery Practices,” 20 June 2001, http://www.ada.org/prof/pubs/daily/0106/0620acc.html (8 April 2002).
Rebecca Twersky, chair, Anesthesia Patient Safety Foundation, Committee on Ambulatory Surgical Care, interview with Elizabeth Lapetina, 2 January 2001; Luz, “JCAHO Offers Accreditation”; and American Society of Anesthesiologists, “Office-Based Anesthesia and Surgery,” 2001, http://www.asahq.org/PublicEducation/OBAbrochure.htm (4 April 2002).
American Association for Accreditation of Ambulatory Surgery Facilities, “About AAAASF,” http://www.aaaasf.org/AboutAAAASF/about.cfm (29 November 2001).
Lazarov, “Office-Based Surgery,” 385; and J.H. Sutton, “Office-Based Surgery Regulation: Improving Patient Safety and Quality of Care,” Bulletin of the American College of Surgeons (February 2001): 8-12.
J.F. Arens, “Anesthesia for Office-Based Surgery: Are We Paying Too High a Price for Access and Convenience?” Mayo Clinic Proceedings (March 2000): 225-228; and F.M. Grazer and R.H. de Jong, “Fatal Outcomes from Liposuction: Census Survey of Cosmetic Surgeons,” Plastic and Reconstructive Surgery (January 2000): 436-448.
American Society of Plastic Surgeons, “2000 General Information,” http://www.plasticsurgery.org/mediactr/stats-03.pdf (3 April 2002).
Sutton, “Office-Based Surgery Regulation.”
The twenty states with outpatient/ambulatory center legislation are: Arizona, California, Delaware, Florida, Georgia, Indiana, Kansas, Montana, Nebraska, Nevada, New Hampshire, New Mexico, New York, North Carolina, Ohio, Oregon, Pennsylvania, Tennessee, Utah, and Wyoming. Accreditation Association for Ambulatory Health Care, “About AAAHC,” http://www.aaahc.org/about/about2.shtml (29 November 2001). In addition, Oregon has a voluntary regulation system for office-based practices, and the Mississippi Board of Medical Licensure requires reporting of office-based adverse events as of January 2002. R. Twersky, “Standards for Office Anesthesia Vary Widely or Do Not Exist,” Anesthesia Patient Safety Foundation Newsletter (Spring 2000); L.O. Prager, “Florida Bans Some Office-Based Surgeries,” American Medical News, 4 September 2000; and AAAHC, “Legislative Information: Ambulatory Health Care Accreditation State Laws and Regulations,” wsm.sgsnet. com/cgi-bin/osform/headline?osform_template=display.oft&oid=abcaaa3105fbf2ab (17 May 2002).
C.J. Coté et al., “Adverse Sedation Events in Pediatrics: A Critical Incident Analysis of Contributing Factors,” Pediatrics 105, no. 4 (2000): 805-814.
R.B. Rao, S.F. Ely, and R.S. Hoffman, “Deaths Related to Liposuction,” New England Journal of Medicine (13 May 1999): 1471-1475.
Grazer and de Jong, “Fatal Outcomes from Liposuction.”
A.M. Minino and B.L. Smith, “Deaths: Preliminary Data for 2000,” National Vital Statistics Reports 49, no. 12 (Hyattsville, Md.: National Center for Health Statistics, 2001).
Rao et al., “Deaths Related to Liposuction”; and Coté et al., “Adverse Sedation Events in Pediatrics.”
http://amarillo.com/stories/1999/03/18/usn_about.shtml L. Neergaard, “Deaths Raise Concern about Sedation in Offices,” Associated Press, 17 March 1999.
Arens, “Anesthesia for Office-Based Surgery.”
Joint Commission on Accreditation of Healthcare Organizations, “Office-Based Surgery Accreditation Overview,” http://www.jcaho.org/accred/amb/obs_accred_overview.html (29 November 2001).
New York State Senate Committee on Investigations, Taxation, and Government Operations, “Problems of Office Surgery,” February 1999, 188.8.131.52/Docs/surgery.htm (29 November 2001).