When the Airbus A320 took off from New York City'south LaGuardia Airport yesterday, the air temperature outside was well below freezing—around xx degrees Fahrenheit (–half-dozen.vii degrees Celsius). The 150 passengers on board no incertitude assumed they would spend the next hour and a one-half in the cushioned seats of a cozy, warm airplane cabin en road to Charlotte, N.C. Piffling did they know that merely minutes subsequently takeoff they would instead exist bobbing on the frigid waters of the Hudson River off Manhattan's west side.

But minutes after Capt. Chesley Sullenberger orchestrated a nigh-perfect emergency water landing (after a standoff with a flock of Canada geese reportedly knocked out both engines), h2o began seeping into the airplane. Ii passengers treated for hypothermia at nearby Saint Luke's–Roosevelt Hospital emergency room said that the water was waist-high almost immediately, according to Gabe Wilson, associate medical manager of the hospital'south emergency medicine section. According to media reports, some of the passengers were submerged upwards their necks in h2o once they had evacuated the plane and awaited rescue.

"They were all shaking from both the [cold] temperature and stress," says Wilson, who treated eleven of the plane's passengers for hypothermia, a potentially fatal condition that occurs when the body cannot generate enough heat to compensate for the warmth it loses.

Many of the symptoms of hypothermia resemble those of a drunken daze: sleepiness, clumsiness, confusion and even slurred speech. Doctors too cheque for shivering, a weak pulse, low claret pressure level, and a torso temperature below 96 degrees F (35.5 degrees C). (Normal body temperature is 98.vi degrees F, or 37 degrees C.)

Fortunately, none of the passengers that he treated had torso temperatures below 95 degrees F (35 degrees C), Wilson says, calculation that all they needed to warm up were Bair Huggers, special blankets hooked to a heater which send warming air currents over the body.

But what if the passengers had not been rescued so fast? What would take happened if they had spent hours wading or swimming through the Hudson, or in any cold water, pending rescue? We asked Christopher McStay, an emergency room dr. at New York City'south Bellevue Hospital Middle nigh the potential consequences and treatments for hypothermia.

[An edited transcript of the interview follows.]

How long can a person survive in water that is 41 degrees F similar the Hudson was when the plane went down?

When you lot starting time become into extremely common cold water in that location is this weird response chosen a cold shock response. People commencement to hyperventilate immediately. For i to 3 minutes yous exhale very fast and deep, uncontrollably. If you go underwater, you could eat h2o and die. …I tin't tell you how oft this occurs but it's certainly a very real phenomenon. One time that response goes away, you lot're fine…for awhile.

Generally, a person tin can survive in 41-caste F (5-degree C) water for 10, 15 or twenty minutes before the muscles go weak, you lose coordination and strength, which happens because the blood moves away from the extremities and toward the eye, or core, of the trunk.

There are many factors that determine how fast a person submerged in water cools. People who are obese, who have a lot of soft tissue that provides a lot of insulation, are likely to last longer than lanky people, because the torso fat provides insulation. Another gene is how much of the body is really underwater. (H2o conducts heat away from the body much faster than air does, even if the water temperature is xx degrees college than the air temperature. So, the more the body is submerged, the faster its heat will exist tuckered, according to Craig Heller, a Stanford University physiologist). If you accept a flotation device that you lot can pull yourself on top of, y'all are much better off.

How cold does the water have to be to put a person at risk for hypothermia?
Fifty-fifty water temperatures as high every bit 75 and fourscore degrees F (24 and 27 degrees C) tin can be dangerous, but it would most likely take much longer than 15 minutes to go debilitated. There is no set fourth dimension for when hypothermia will gear up in, but generally the colder the water, the faster it happens.

And then if you find yourself submerged in icy-cold water, what should you lot do?
If you have a flotation device, you should go on top of that device and hug yourself to keep as much of your body away from the water every bit possible. If yous keep your arms and legs in tight, close to the core of the trunk, y'all keep your limbs from existence exposed to the cooling h2o. If you do not have a flotation device, become out of the water as fast equally you perhaps can.

What is the difference between frostbite and hypothermia?
Frostbite is actually the freezing of tissue [such every bit skin, muscle and nervus tissue]. Suppose you're on meridian of Mount Everest and you're arranged up; your core temperature is 98.vi degrees F. If you take off your gloves, you take exposed that area and it may get frostbite. That's not hypothermia. Hypothermia is a drop in the core temperature of the trunk.

When are you in danger of getting frostbite and were these survivors at take a chance?
For frostbite to occur, the tissue actually has to freeze—meaning a dip to 32 degrees F (0 degree C) or lower. The parts of the body submerged in water are not in danger of becoming frostbitten, because the water temperature (41 degrees F) is not freezing. However, the parts of the trunk exposed to air are at adventure because the air temperature is twenty degrees F (–7 degrees C), which is below freezing.

Can yous die from frostbite?
You lot can certainly die from frostbite, but that is exceptionally rare. Unremarkably when people dice from frostbite, it'due south from some complication downwardly the road such as gangrene, the decay and decease of tissue which occurs when information technology does non receive enough blood or becomes infected.

What do you exercise to care for hypothermia?
If your body temperature is to a higher place 95 degrees F and you lot're healthy, your body will warm itself upward and you lot generally don't need handling.

If your body is xc degrees to 95 degrees F (32 to 35 degrees C) and you lot look okay, nosotros'll practise things like put a warming blanket effectually you. If your temperature drops much lower, we might give you an 4 with warm fluids, insert a breathing tube to supply the lungs with warm air, and insert tubes through the rima oris and urethra to put hot saline into the stomach and bladder, respectively. Heating from the inside (by introducing these fluids) helps warm the trunk's core tissues faster than heating the body from the outside (past using blankets or putting a person in a warm environment, for case).

If a patient comes into the emergency room with a body temperature between 70 and 80 degrees F (21 and 27 degrees C), they oft appear dead—or are expressionless. Cardiac arrest oft occurs in this temperature range. Even if it appears someone has passed away, it is still of import to warm them (using the techniques described above), because with this caste of hypothermia the heart can slow to a point at which doctors cannot even discover it. Thus, they could make the fault of presuming someone dead who is actually still alive.

For these unconscious patients, we too practise cardiopulmonary resuscitation (CPR) on them and often utilize a cardiopulmonary bypass (middle–lung) machine that will actually oxygenate the blood and provide a pulse for them.