When patients and their families think about risks associated with their surgeries, they usually think about unexpected systemic failures, post-operative infections or other complications that may occur at the surgical site, and anesthesia problems. Fortunately, these risks generally are quite small, and improvements in analgesic medications and techniques have remarkably decreased the problems associated with significant post-operative pain.

Patient positioning, an often overlooked risk, may cause immediate intraoperative problems as well as long-term disability and pain. Examples of positioning problems include:

• Respiratory problems. Some positions can restrict movement of the rib cage or diaphragm and impede airflow (most often with obese patients).
• Circulatory problems. Lithotomy positions and severe head-down positions used in some laparoscopic procedures may compromise blood flow to the lower extremities or venous bloods return to the heart.
• Nerve, muscle injuries. Nerves, muscles, tendons, joints and blood vessels may be compressed or stretched during surgery.
• Soft tissue injuries. Friction and pressure on soft tissues, especially over bony prominences, may result in changes ranging from mild irritation to severe pressure-induced ischemia.

Because sedated or anesthetized patients often can't shift their bodies during surgery, even short procedures can lead to post-operative soft tissue problems, peripheral neuropathies or painful localized myalgias if patients are positioned improperly. Some of these post-op problems are unavoidable in order to provide appropriate surgical access, especially for unexpectedly prolonged procedures. Others are problems that develop post-operatively and are not associated with intraoperative care. However, you can prevent or reduce the frequency of many of these injuries by using the right equipment and reasonable positioning techniques. Here are seven strategies to assist with intraoperative positioning.

1. Put a pre-op plan in place
In general, if patients are sedated or anesthetized for less than an hour, their chances of sustaining positioning injuries are slight. No matter what the length of the procedure is, however, assess these factors, all of which may affect positioning:

• body habitus;
• skin condition;
• current medications;
• limitations of range of motion for extremities and spine;
• pre-existing abnormalities (such as back problems), disorders (such as nerve dysfunction) or any generalized medical conditions that may impact blood flow or joint movement (such as rheumatoid arthritis)
• the presence of implants, stomas and other soft-tissue variances; and
• previous surgeries and any complications.

Curiously enough, advanced age isn't an independent risk factor for positioning-related problems - an otherwise healthy 82-year-old may be less vulnerable than a diabetic, overweight 35-year-old. However, older people tend to have reduced flexibility and poorer peripheral circulation than younger people, factors that may them more susceptible.

Note that some problems are unique to specific patient groups: Men who are 40-to-70 years old who undergo abdominal or pelvic procedures, for example, have a higher risk of developing post-op ulnar neuropathy. Women who are older than 60 years of age have an increased risk of developing obturator and lateral femoral cutaneous neuropathies after procedures performed while they are positioned in a lithotomy position (cystoscopies and gynecologic outpatient procedures, for example).

Use the pre-op assessment to create a positioning plan before you enter the OR. All members of the team should know how to maintain patients in the required positions before, during and after surgery and how to shift them smoothly from one position to another, if needed.

2. Work as a team
The surgeon, anesthesia team and perioperative staff all play important roles in positioning patients.

• The surgeon should inform the team about the position(s) needed for appropriate surgical exposure and the approximate time the case will take.
• The staff should be thoroughly familiar with the equipment, including the OR table and available attachments and padding. They should understand how the equipment influences positioning.
• The anesthesia team should determine the patient's ability to attain positions comfortably without excess stress on the extremities, back, neck and other structures. They should also understand the potential physiologic hazards of various surgical positions for specific patients (for example, those with pre-existing disorders such as cardiomyopathy, hypertension and neuromuscular diseases, or more specifically, thoracic outlet obstruction for prone-positioned patients).

Anesthesia providers are probably best suited to integrate all of the patient information, but the entire team needs to understand positioning.

3. Assemble the proper equipment
Surgical tables should feature quality mattresses, a variety of attachments and, preferably, electric or pneumatic controls. Manually controlled tables may be perfectly adequate and often are less expensive than automatic varieties, but the latter are generally much easier to adjust and often help improve the ergonomics of positioning patients.

The attachments you'll need will depend on the types of procedures performed. In general, attachments should help retain and support patients, especially the extremities and head, without placing point or band-like pressure on major nerves and vessels. Make sure they are padded, fully adjustable and stable. When possible, they should offer support of the full body part, thus dispersing pressure over a broad area. Practice attaching and removing them from the OR table so you can do this smoothly during procedures.

There are many different types of pads and gels that disperse point pressure across a larger area or eliminate pressure on protuberances altogether. Some are composed of materials with elasticity and other mechanical attributes that theoretically may cushion protuberances better than other materials. I'm not aware, however, of any independent clinical studies that prove any specific cushioning material to be superior to another in reducing the frequency of positioning-related problems such as skin damage or peripheral neuropathies. Therefore, it appears to be just as effective to use towels and blankets for point pressure dispersion as more expensive commercial pads. There are times, however, when commercial pads provide better support and pressure dispersion than you might obtain with towels and blankets. I generally use whatever materials are readily available, as long as they meet my positioning goals.

Remember that cushioning materials aren't always entirely effective. In many instances, patients who were apparently well padded subsequently developed pressure-associated injuries. Men, for instance, are particularly susceptible to ulnar nerve injury, even if the arm is kept on padded surfaces. Recent studies have found that some patients develop these problems post-operatively. Even medical (non-surgical) patients can develop these same problems.

4. Take time to reassess
During a procedure, the team will sometimes need to shift a patient, adjust the table, or add or remove a positioning device. When these situations occur, immediately reassess the patient's new position from top to toe, as there may be areas previously protected that now have become vulnerable to injury. For example, if patients are shifted from prone to lateral positions, the downside ears may fold, becoming ischemic over time. In prone-positioned men, penises may get impinged between pelvises, legs and supporting cushions. Also reassess patients when cases last longer than anticipated. A recent study showed that patients placed in the lithotomy position sustained very few positioning injuries in the lower extremities during the first hour of surgery - each additional hour, however, posed a 100-fold increase in risk for neuropathies. For patients placed in the lithotomy position, change to a supine position during a prolonged procedure when lithotomy is no longer needed.

5. Be aware of ergonomics
We all know about the ergonomic injuries that they may incur when lifting and transferring sedated or anesthetized patients. But surgeons and staff also may become injured when:

• Holding or manually maintaining patients in unique positions, such as holding a leg in a unique position for a prolonged period.
• Providing care in unusual positions, such as holding an airway on a patient in an unusual position.
• Operating in unusual positions, such as excessively bending or oddly maneuvering to perform a difficult laparoscopy.

Table attachments and other equipment, such as padded, adjustable surgical stools, may help alleviate these problems. Team members should also have a basic understanding of ergonomics so they know how to use the equipment optimally.

6. Perform a thorough post-op assessment
Start the post-op assessment in the OR before patients have recovered from their anesthetics. Examine any areas that were under direct pressure, and check for reddened or discolored areas that may indicate tissue injury. Once patients awaken, recovery personnel should ask about and document numbness or tingling in their hands, legs or feet before discharge.

Some injuries, especially those of the lower peripheral nerves, show up immediately. But patients do not note many upper extremity neuropathies until several days after their procedures. This suggests differences in etiologies of these nerve injuries, with lower extremity nerve injuries more likely to be associated with the intraoperative period and those of the upper extremities to evolve post-operatively.

7. Document everything
Positioning problems often result in medicolegal actions. In some cases, what seems to be a positioning injury turns out to be an exacerbation of a pre-existing condition. While the best way to prevent a positioning malpractice action is to practice good technique, it's also important to document that you're doing so. I remember a case in which a patient was diagnosed with ulnar neuropathy several weeks after a surgical procedure. Prompted by a lawyer, the patient filed a malpractice action against the anesthesia team. He noted in his deposition that he awoke in the recovery room with tingling along the ulnar nerve sensory distribution. This patient "forgot" that, as a participant in a prospective ulnar neuropathy study, he was examined daily for the first seven days after his procedure. He had no symptoms or signs of ulnar neuropathy during those seven days. Once reminded of his participation in the study, he dropped his malpractice claim.

Every case, every patient
Safe and comfortable positioning is one of the few things common to every case and every patient. By making sure that every member of your OR team knows the scope of potential positioning problems, you'll achieve superior outcomes.