It took anesthesiologist Becky Wright, MD, 5 attempts to intubate Mae Ellen Williams, a 5-foot-2-inch, 215-pound patient who went to Baptist Memorial Hospital in Memphis, Tenn., for a laparoscopic cholecystectomy. According to court records, the procedure was uneventful. But after being extubated, Ms. Williams was unable to breathe on her own. Her vital signs became undetectable. She slipped into a coma and died 2 years later. A lawsuit filed by the woman's family accused Dr. Wright of failing to perform an awake intubation and of making more than 3 attempts at inserting the endotracheal tube, which allegedly led to airway swelling and subsequent ventilation difficulties. Did Dr. Wright follow the standard of care? Was she prepared to handle a difficult airway? That argument would play out in court — a judgment on a technicality was in Dr. Wright's favor — but what's important here is the underlying clinical lesson. "With proper planning, obese patients don't necessarily have more difficult airways than the general population," says William Loder, MD, of the department of anesthesiology at Geisinger Medical Center in Danville, Pa. "But if you don't plan ahead and can't intubate them, you'll be in a world of trouble in a hurry."

Assess and act
Pre-planning is the single most important step in any airway management scenario, says William Landess, CRNA, MS, JD, the director of anesthesia at the Palmetto Health Richland Campus in Columbia, S.C. "Guarding against hypoxemia is the No. 1 concern, even more so in the obese patient," he explains. "There are a variety of methods, techniques and adjuncts that can be used to protect the obese patient's safety." Your providers should be comfortable in the use of them all, he says (see "Difficult Airway Tools and Tips" on page 18).

Which patients should raise red flags during pre-op assessments? Typically, a body mass index (BMI) of 25 is the tipping point of health, according to Mr. Landess. "A quick look at a patient should clue you in to the potential for airway issues," he says, "but a thorough physical exam and review of a patient's health history will hone in on specific predictors for trouble." When you assess the airway, look for a small mouth, large tongue (macroglossia), redundant tissues, overbite, receding chin (micronathia), a short neck and neck circumference of 19cm or greater (which correlates with difficult intubation), says Mr. Landess. A Mallampati score — which measures the visibility of the oral cavity — of 3 or 4 could be predictive of a difficult intubation.

BMI alone doesn't always indicate possible airway issues, says Davide Cattano, MD, PhD, assistant professor and medical director of the pre-operative anesthesia clinic at the University of Texas Medical School at Houston. Such factors as sleep apnea and upper airway obstructions greatly impact the ease with which airways can be secured and managed. And while not all obese patients have airway issues — some heavy individuals carry excess weight in areas other than the neck — they often have a variety of anatomical attributes that serve as airway detractors, says Mr. Landess. "Physical size makes all aspects of airway management more difficult," he adds. "A high level of suspicion is demanded in this patient population."

Airway? What airway?
Benjamin Jacobs, MD, anesthesiologist at Paoli Surgery Center in suburban Philadelphia, says he avoids airway complications by sidestepping them altogether. "A difficult airway is arguably the most serious complication we can encounter in the outpatient setting," he says. "By using regional anesthesia on all our obese patients, we take that issue out of the care equation."

Mr. Landess concurs that regional anesthesia is an effective option in caring for obese patients, but believes it's one that's often overlooked by providers faced with the daunting task of locating anatomical landmarks needed to place effective blocks. He suggests employing ultrasound guidance to target those hard-to-find nerves.

Dr. Jacobs agrees that locating nerves in obese patients can be a challenge, but says he has no trouble placing blocks armed with a standard nerve stimulator. Whether your providers use conventional approaches or more advanced visualization technology, don't ignore the ultimate benefits of using local blocks in heavier patients. "Pain control is often the result of properly placed regional anesthesia, allowing for a decreased use of parenteral narcotics," says Mr. Landess. "And narcotics are notorious for decreased ventilatory drive, which could lead to hypoxia in an already compromised patient population."

Positions to succeed
Putting obese patients in positions that help providers manage the airway is crucial, but its importance is sometimes ignored, even though "positioning may be the difference between securing an airway and compromising the patient," says Mr. Landess. Heavy truncal weight makes ventilation more difficult, he points out. "Raising the surgical surface's height 30 ? will unload the diaphragm, making ventilation easier."

Placing the patient's head in this "ramped" position allows for anatomical alignment of the axes, which generally improves intubation success, adds Mr. Landess, who says the 30 ? reverse Trendelenberg in combination with the ramped position may provide the best protection for the obese patient.

In the August 2011 issue of Anesthesiology News, Dr. Cattano says the aim of the ramped position — achieved with specially designed positioning devices or stacked pillows or sheets — is to align the oral, pharyngeal and laryngeal axes, which appears to improve ventilation and laryngoscopic views and increase rates of successful intubations. He also touts the benefits of the beach chair and sitting positions, which "help prevent airway collapse in patients who are obese or have obstructive sleep apnea."

Dr. Cattano noted in the report that recent studies have shown video-assisted laryngoscopy performed on patients with necks in the "neutral" position to be more effective in preventing oxygen desaturation during intubation than conventional direct laryngoscopy performed on patients in the ramped position.

Video laryngoscopy, which provides a direct view of the glottis and is considered by a growing number of providers to be the standard of care for airway management, reduces the amount of force needed to manipulate the patient's jaw and neck, says Dr. Cattano. His research has also found that video laryngoscopy provides line-of-sight views of the airway's anatomy, meaning the endotracheal tube can be placed more easily and quickly in obese patients with difficult airways.

A growing problem
Obesity is pandemic in America. Two-thirds of the population is considered obese and pediatric obesity has tripled since the 1970s. "Obviously that translates to our patient population," says Mr. Landess, adding that obesity preventative programs are falling on deaf ears. That means you'll be faced with caring for heavier and heavier patients in the coming years. As always, he says, "Err on the side of patient safety when caring for this, or any, patient population."