5. "Yes, we take your insurance, but we're not sure about the anesthesiologist."

The last thing on your mind before surgery is making sure every doctor involved is in your network. But because the answer is often no for anesthesiologists, pathologists and radiologists, what's a patient to do?

Los Angeles entertainment lawyer and patient advocate Michael A. Weiss repeatedly turned away out-of-network pain-management doctors on a visit to the hospital.

If you're alert enough, ask for someone in your network. If you're seeing a physician or going to any medical facility, call your insurance company for a current list of network physicians, hospitals and labs. Also, if the referral appointment is being made by your primary-care physician, request the scheduling staff to find specialists, hospitals and labs in your network. Then verify that with your insurance company, says Mary Jane Stull, the president and CEO of The Patient's Advocate, a South Bend, Ind., company that helps people with medical insurance claims.

Medical providers can drop out of a network between the preoperative appointment and the actual surgery date. And if you know your procedure will be out-of-network, call the medical providers: physicians, surgeon, anesthesiologist and hospital. It might be worthwhile to try to negotiate a price and payment plan with the billing department, Stull says.

6. "Sometimes we bill you twice."

Crack the code of medical bills, and you may find a few surprises: charges for services you never received or for routine items, such as gowns and gloves, that shouldn't be billed separately. Clerical errors are often the reason for mistakes. One transposed number in a billing code can result in a charge for placing a catheter in an artery versus a vein -- which can come to a difference of thousands of dollars.

So how do you figure out if your bill has incorrect codes or duplicate charges? Start by asking for an itemized bill with a breakdown of all charges clearly defined, says Dr. Geni Bennetts, a principal of Resolve Healthcare Billing Advocacy in Napa, Calif. Some telltale mistakes: charging for three days when you stayed in the hospital overnight, a circumcision for your newborn girl or drugs you never received. Ask the hospital's billing office for a key to decipher the charges, or hire an expert to spot problems and deal with the insurance company and doctors (you can find one at Medical Billing Advocates of America).

Their expertise typically will cost anywhere from $65 to $85 an hour, a percentage of the savings, or some combination of the two. If you want to be your own billing sleuth, talk to the highest-ranking administrator you can find in the hospital finance or accounts office to begin untangling any mistaken codes.

7. "All hospitals are not created equal."

How do you tell a good hospital from a bad one? For one thing, nurses. When it comes to their own families, medical workers favor institutions that attract nurses. But they're harder to find as the country's nursing shortage intensifies; by 2020, there will be a deficit of about 1 million nurses. Low nurse staffing directly affected patient outcomes resulting in more problems, such as urinary-tract infections, shock and gastrointestinal bleeding, according to a 2001 study by Harvard and Vanderbilt University professors.

Another thing to consider: Your local hospital may have been great for welcoming your child into the world, but that doesn't mean it's the best place to undergo open-heart surgery. Find the facility with the longest track record, best survival rate and highest volume in the procedure; you don't want to be the team's third hip replacement, says Samantha Collier, the chief medical officer of HealthGrades, which rates hospitals.

An American Nurses Association website lists "magnet" hospitals -- those most attractive to nurses -- and a call to a hospital's nurse supervisor should yield the nurse-to-patient ratio.

A good tool to help consumers evaluate hospitals is a website operated by the Department of Health and Human Services that compares hospitals against national averages in certain areas. The site includes information about how well hospitals care for patients with certain medical conditions as well as the results of surveys given to patients asking them about their stay, says Anne F. Weiss, a senior program director at the Robert Wood Johnson Foundation, a health care nonprofit.

8. "Most ERs are in need of some urgent care themselves."

A 2007 study from the Institute of Medicine found that hospital emergency departments are overburdened, underfunded and ill-prepared to handle disasters as the number of people turning to ERs for primary care keeps rising. An ambulance is turned away from an ER once every minute due to overcrowding, according to the study; the situation is exacerbated by shortages in many of the on-call backup services for cardiologists, orthopedists and neurosurgeons.

Nearly three-quarters of ER directors reported inadequate coverage by on-call specialists versus 67% in 2004, according to a 2006 survey conducted by the American College of Emergency Physicians.

If you can, avoid the ER between 3 p.m. and 1 a.m. -- the busiest shift. For the shortest wait, early morning -- anywhere from 4 to 9 a.m. -- is your best bet. If you're having severe symptoms, such as the worst headache of your life or chest pains, a triage nurse is trained to recognize whether your symptoms constitute a medical emergency. Just know that emergency department staff are strained during busy hours, but giving "honest descriptions of your symptoms and truly working with the staff is the best way to advocate for yourself and your family as a patient," says Darria E. Long, a doctor at Yale's department of emergency medicine.

9. "Avoid hospitals in July like the plague."

If you can, stay out of the hospital during the summer, especially July. That's the month when medical students become interns, interns become residents, and residents become fellows and full-fledged doctors. In other words, a good portion of the staff at any given teaching hospital is new on the job.

Summer hospital horror stories aren't just medical lore: The adjusted mortality rate rises 4% in July and August for the average major teaching hospital, according to the National Bureau of Economic Research. That means eight to 14 more deaths occur at major teaching hospitals than would normally without the turnover.

Another scheduling tip: Try to book surgeries first thing in the morning and preferably early in the week, when doctors are at their best and before schedules get backed up.

10. "Sometimes we don't know how to keep our mouths zipped."

Contrary to what you might think, sharing patient information with a third party is often perfectly legal. In certain cases, the law allows your medical records to be disclosed without asking or even notifying you. For example, hospitals will hand over information regarding your treatment to other doctors, and they will readily share those details with insurance companies for payment purposes.

That means roughly millions of entities that are loosely involved in the health care system have access to that information. These parties may even pass on the data to their business partners, says Deborah Peel, the founder of the Patient Privacy Rights Foundation in Austin, Texas.

If you want to access your medical records, you don't have to steal them like Elaine did on an old episode of "Seinfeld" after she learned a doctor had marked her as a difficult patient. You are legally entitled to see, copy and ask for corrections to your medical records. For your own "Patient Privacy Toolkit," visit the Patient Privacy Rights Foundation's website.

This article was reported by Reshma Kapadia and Lisa Scherzer for SmartMoney.