Of all the non-fatal complications of surgery, perhaps none is more traumatizing, and more unexpected, than postoperative vision loss. Patients rarely, if ever, anticipate the possibility that when they awaken from unrelated surgery – on their back or hip, for instance – they will do so with severely impaired vision, or no vision at all. Yet this severe complication can and does occur — often as a consequence of surgical or anesthesiology malpractice — leading to moderate to severe vision impairment, limited field of vision, or even total blindness.
The experienced medical malpractice attorneys of Passen & Powell were not surprised to learn that postoperative vision loss is on the rise. While rates of postoperative vision loss vary from study to study, at least one study has found that this injury occurs in as many as 3.6 percent of cardiopulmonary bypass surgeries. When all operations not involving the eye are considered, however, some studies have found rates of postoperative vision loss as low as one in every 60,965 surgeries. Whatever the rate, however, two separate studies have recently confirmed an increase in cases of this devastating surgical mishap.
Yet scientists still have little to know understanding of the causes of postoperative vision loss. What is known is that postoperative vision loss is tied to anesthesia – but doctors’ understanding of exactly how this works is severely limited. Researchers have identified several known causes, but many cases of postoperative vision loss cannot be attributed to these factors. While some researchers have additional theories as to possible causes, such as the release of stress hormones during surgery, in many cases of postoperative vision loss it is unclear how the patient’s anesthesia caused the vision loss.
Some of the known causes of postoperative vision loss are direct pressure to the eye, air emboli (or atheromatous), prolonged hypotension and anemia during anesthesia, and inadequate or improper drainage of the veins in the globe of the eye. In rare cases, postoperative vision loss can be caused by improper administration of local anesthetic, without aspiration, which in turn allows intravascular injection and the potential for fluid emboli in the eye.
These causes are often themselves caused by improper positioning of the patient prior to surgery. While the optimal surgical position varies, several factors must be considered:
- the site of the operation, and where the surgeon will need access
- the age, height and weight of the patient,
- the type of anesthesia being used, and
- the type and severity of pain experienced by the patient.
Surgeons and anesthesiologist must use special care to avoid selecting positions that place pressure on the eyes, particularly in heart and spinal surgeries, where postoperative vision loss is the most common. In particular, the prone position for surgery is known to increase the risk of postoperative vision loss. The failure to consider alternate positions, where possible, or to carefully monitor optic pressure in surgical patients in the prone position, may constitute medical malpractice. But whatever the surgical position chosen, to avoid postoperative vision loss the physician and anesthesiologist must pay careful attention to pressure and drainage in the eyes.
Likewise, the buildup of cerebrospinal fluid during anesthesia can cause pressure in the eye, and edema of the optic disc. Cerebrospinal pressure leads to pressure on the optic nerve, and inside the optic nerve sheath. Because the retinal artery and vein pierce this sheath, then enter the eye itself with the optic nerve, when pressure increases this area can swell into the eye cavity, leading to permanent vision loss.
While surgeons and anesthesiologists are eager to portray postoperative vision loss as just another potential side effect of surgery, the causes listed above demonstrate that it is, in fact, often a preventable medical error. When physicians and surgeons fail to take the proper precautions to prevent optical pressure or fluid buildup, or allow extended hypotension and anemia to deprive the eye of oxygen, then they may be guilty of medical malpractice.
Nor is postoperative vision loss the only long-term consequence of general anesthesia. Indeed, in recent years, researchers have confirmed that the risks of general anesthesia, once thought to evaporate shortly after a patient awakens, in fact continue for years. In a study presented at the American Society of Anesthesiologists’ annual meeting, researchers demonstrated that the longer the time spent under general anesthesia, the greater the risk that a patient will die in the two years following surgery. And although the patients studied were all having non-cardiac surgery, heart attacks (and cancer) were the most common causes of death.
Likewise, a study published in the journal Anesthesia & Analgesia found the the length of time under general anesthesia increased the risk of dying in the following year. Again, all the surgeries in the study were non-cardiac surgeries, but heart attacks and cancer were the primary causes of death.
For a free consultation with a top-rated Illinois medical malpractice lawyer at Passen & Powell, call us at (312) 527-4500.