Anesthesia is a weird field relative to other medical specialties. We don't have a clinic where we get to talk to patients at length, going into great detail about their medical histories and forming a plan of action afterwards. We don't see patients in multiple follow up visits. Besides pathology, anesthesia is one of the few fields where the doctor talks very little with the patient. But the 10 to 20 minutes that we do talk to our patients, right before surgery, are among the most precious few minutes that any patient can spend with their doctor. This encounter, formally referred to as the preoperative evaluation, gives us the information we need to know in order to give you a safe and effective anesthetic.
Most of what we ask patients in the preoperative evaluation is pretty standard stuff. What are your medical problems? Related to that, what medicines do you take? Are you allergic to anything? In almost any doctor's office, in any specialty, you'd get these kinds of questions. There are a few more questions in our evaluation, some of which are asked by others, but most of which are unique to us, or at least focused on more closely by us.
I'll put these in a list.
1. When was the last time you ate something? This is perhaps the single most important question to answer correctly before getting anesthesia. The answer needs to be either "nothing since midnight" or "nothing in the last 6 hours". The question I always get from patients is "why?". The short answer is that anesthesia and a full stomach are a bad and potentially fatal combination. I'll explain in detail in a later blog.
2. Do you smoke? Doesn't every doctor ask that? And if you smoke, isn't it friggin'
annoying? For us anesthesiologists, it's a big deal, because if you are going to sleep, we may choose to place a breathing tube through your vocal cords and into your trachea to help you breathe, known as an intubation. If you smoke, it means that your upper airways and trachea are very reactive and sensitive to anything touching them, like a breathing tube. Everyone finds the breathing tube irritating, but smokers really hate it, and sometimes, their upper airways can constrict severely in response to it, a phenomenon known as bronchospasm. It is dangerous and can cause the flow of oxygen to the lungs to decrease significantly. There are lots of other anesthesia related issues with smoking. Smokers generally have worse lung function that nonsmokers, with lower baseline oxygen levels, and they are less responsive to oxygen in general. They produce significant amounts of mucus, which can clog the breathing tube and make it harder to give anesthetic gas and oxygen. If you smoke, there's nothing I can do about it, of course, but knowing it helps me prepare for what might happen and work around it.
3. Do you have any loose teeth? Can you open your mouth? These go along with the whole intubation theme. If you have teeth that are loose, it is theoretically possible that they could be damaged when the breathing tube is either placed or removed. It is rare but possible. And if you have caps, crowns, veneers, or other expensive work on your teeth, especially the front ones, we need to know that as well for the same reason. And as for opening your mouth, that tells us another very important piece of information. How wide you open your mouth, how big your tongue is, how long and wide your chin is - all of these tell us how easy or how difficult it will likely be to do your intubation.
4. Have you ever been told you snore? Kind of a personal question, huh? Not everyone asks it, but I do, and it tells me about how you'll act right after you fall asleep, before I've done the intubation. If you snore, it means you likely have a lot of extra soft tissue in your mouth which vibrates to cause the snoring, and which can collapse when under anesthesia, causing your airway to obstruct. This can get dangerous very quickly. The snoring question also leads to other issues, most notably obstructive sleep apnea, which also greatly increases the risk of going under anesthesia.
5. Has anyone in your family ever had a problem with anesthesia? Usually the answer we get is along the lines of how someone's mom or grandma threw up after anesthesia, but what we're looking for is a rare, usually hereditary, and potentially fatal reaction to anesthesia known as malignant hyperthermia (MH). People with MH develop extremely high and potentially fatal fever in response to very specific anesthetic agents. If caught in time, it can usually be treated, but it's scary. People with a personal or family history of MH can still receive anesthesia, but we need to know that history beforehand, because the OR and anesthesia machines have to be prepared in a very specific way to ensure safety. Don't worry if you don't know all the details about how your grandfather had some weird reaction to anesthesia 70
years ago. If we're the least bit suspicious, you'll get the safe (called a "non-triggering") anesthetic.
6. Do you drink? Use drugs? This is really important to answer truthfully, because lying can literally mean the difference between remembering surgery or not - or between life and death. If you drink alcohol heavily, the amount of anesthesia you require to stay asleep and have amnesia of the surgery is increased. Makes sense, huh? So tell us. As for drugs, they too increase your tolerance to anesthesia, especially heroin or other opioids. The real dangerous one, though, is cocaine. Cocaine sensitized and desensitizes your brain to certain drugs in dangerous ways. Most notably, cocaine in combination with certain blood pressure meeds used in anesthesia can cause extremely high, potentially fatally high, blood pressure increases. Or it can cause the blood pressure to sink to nothing, extremely resistant to all but the strongest drugs. If you use cocaine, we've gotta know that! I don't care or judge how you live your life; I just don't want you to die while receiving anesthesia.
7. How tall are you? How much do you weigh? No, we're not trying to be nosy. A lot of the drugs we give are dosed based on your weight, some on your "ideal" weight, but most on your actual weight. It just helps us be accurate with our drug dosing.
Sunday, August 28, 2011
Saturday, August 27, 2011
Epidurals: advice and hints for moms-to-be
So you're on your way to the hospital to have your baby, and you are determined to have an epidural. Not that you don't already have a zillion things on your mind at this point, but here are some things to keep in mind to help make that epidural experience a positive one:
1. Tell your obstetrician and anesthesiologist about any medical issues you may have. This is soooooooo important I can't overstate it. The most important thing with an epidural is to ensure a comfortable and SAFE experience for you and your baby. Whoever your anesthesiologist will be needs to know all about your medical issues. Certain ones are particularly important to us: problems with high blood pressure during pregnancy? That tells us about risk of pre-eclampsia and possible low platelet counts. Are you taking any blood-thinning medications? Sometimes women at risk for blood clots will be on Lovenox, an anticoagulant given as a once or twice daily injection. If that's the case, the epidural placement needs to be timed around the doses. Sometimes the anesthesiologist may choose not to place it.
Other medical issues worth mentioning are anything to do with your back. If you have structural issues with your back, ie scoliosis, history of back surgery (with or without instrumentation), or simply chronic low back pain, we need to know. All of those things make placing an epidural technically difficult and may potentially decrease its effectiveness. In those situations I'm willing to try the epidural if the woman goes into it with open eyes and full knowledge that it may not work, and that I'll err on the side of stopping before doing
any harm.
2. Be nice. I know it's easier said than done when you're in the worst pain of your life, but try. Your anesthesiologist is doing the best they can, and if they're not there five minutes after you called, its probably because they're putting someone else's epidural...
3. Have the room as empty as you can possibly make it. In some hospitals, like Northwestern, the only three people in the room were the anesthesiologist, the nurse, and the patient. No dads or significant others were allowed. It's not being mean; there are practical considerations at work. First, it's a sterile procedure which means the room should be as clean and clutter free as possible. Second, if a dad faints at the (undoubtedly disconcerting) sight of a large needle in his wife's back, no one is there to help him. The nurse and anesthesiologist are obligated to the mother first. There are stories of dads fainting, hitting their heads, and going to surgery for an intracranial bleed. Third, frankly, it's unsettling having someone you don't know breathing down your neck, looking at what you're doing, or worse yet, telling you what to do.
Where I work now, the policy is up to the individual doctor. I let the dads stay if they insist, but I ask them to stand in front of the mom and hold her hand, comfort her, keep her sitting still, etc.
4. Try to hold still as the epidural is being placed. Let me preface this by saying that I am the biggest pansy on earth when it comes to pain, as are most guys. I wouldn't last 10 minutes in labor. I joke with patients that if dads had the childbearing responsibilities, the human race would've died out thousands of years ago.
That being said, it is incredibly disconcerting for me (and dangerous for you) if you move while I have a large needle in your back, within an inch or so of your spinal cord. Bad things can happen. So try really, really, really hard not to move. Labor must hurt something awful, because women, even the most squeamish ones, eventually sit amazingly still if it means the difference between getting or not getting an epidural. Just gimme five more minutes and your pain will be so much better...
5. If you're at an academic medical center, don't ask an attending to do you your epidural. The falsely enlightened ones who would come to Northwestern when I was a resident would do this, and besides being annoying, it was barking up the wrong tree. By the time I was a senior resident, I had placed literally 400 epidurals, all in a four month span. Any of the attending physicians I was working with had placed...nowhere near that many. They're way too busy supervising and doing administrative tasks and are out of practice. With all due respect to my old attendings, if you must ask someone to place your epidural ask a senior resident, or if you're really savvy, an OB fellow if there are any. Generally, though, a good old junior resident will do the job just fine.
6. Unless you're trying to go without, get the epidural as soon as you can. I'm sure any OB reading this will have a fit, but I still think it's a good idea. Before, the wisdom was that getting an epidural before you were 4 centimeters dilated would slow labor and increase the risk of c-section. But several studies have shown (including one that was completed at Northwestern, by the way) that that is not the case. You'll be comfortable for longer, and should things go awry, the epidural is there for a c-section if needed.
7. The longer you wait, the harder it is to get the epidural. The reason is simple. As your cervical dilation increases and contractions get more intense, they hurt more and it's a lot harder to sit still when the epidural is being placed. Also the strength and intensity of the contractions then are such that it is difficult to get full and quick relief from the epidural. But there's a happy corollary to this one:
8. It's never too late to get the epidural. At least it's never too late from the anesthesiologist perspective. Again, if you can sit still, we can try to place it. I remember on one occasion as a resident where I was asked to place an epidural in a woman who was pushing. They were concerned she would need help delivering by forceps and didn't want her to be uncomfortable. So she stopped pushing, sat up for the epidural, and when she got it, kept on pushing. Amazing. Now if the OB doesn't want it for their own set of medical reasons, that's another story...
9. Don't expect a miracle. In some ways, epidural anesthesia is burdened by its own success. One woman tells another who tells another that her epidural was great, and then that woman comes in to deliver, expecting to do so without a hint of pain. Needless to say, that's simply not realistic. We as anesthesiologists can dose the epidural that way, making you so numb you can't feel anything. The problem is that you won't be able to move your legs, and that will make pushing difficult if not impossible and increase the chance of c-section or instrumented delivery. The OB doctors don't like it when we make patients that numb. Sometimes things like spinal anatomy or the position of the baby can cause issues with discomfort that even the best epidural can't completely fix. The ideal is to feel the pressure of the contractions, so that you can actively push, but without the pain that came with them before the epidural.
1. Tell your obstetrician and anesthesiologist about any medical issues you may have. This is soooooooo important I can't overstate it. The most important thing with an epidural is to ensure a comfortable and SAFE experience for you and your baby. Whoever your anesthesiologist will be needs to know all about your medical issues. Certain ones are particularly important to us: problems with high blood pressure during pregnancy? That tells us about risk of pre-eclampsia and possible low platelet counts. Are you taking any blood-thinning medications? Sometimes women at risk for blood clots will be on Lovenox, an anticoagulant given as a once or twice daily injection. If that's the case, the epidural placement needs to be timed around the doses. Sometimes the anesthesiologist may choose not to place it.
Other medical issues worth mentioning are anything to do with your back. If you have structural issues with your back, ie scoliosis, history of back surgery (with or without instrumentation), or simply chronic low back pain, we need to know. All of those things make placing an epidural technically difficult and may potentially decrease its effectiveness. In those situations I'm willing to try the epidural if the woman goes into it with open eyes and full knowledge that it may not work, and that I'll err on the side of stopping before doing
any harm.
2. Be nice. I know it's easier said than done when you're in the worst pain of your life, but try. Your anesthesiologist is doing the best they can, and if they're not there five minutes after you called, its probably because they're putting someone else's epidural...
3. Have the room as empty as you can possibly make it. In some hospitals, like Northwestern, the only three people in the room were the anesthesiologist, the nurse, and the patient. No dads or significant others were allowed. It's not being mean; there are practical considerations at work. First, it's a sterile procedure which means the room should be as clean and clutter free as possible. Second, if a dad faints at the (undoubtedly disconcerting) sight of a large needle in his wife's back, no one is there to help him. The nurse and anesthesiologist are obligated to the mother first. There are stories of dads fainting, hitting their heads, and going to surgery for an intracranial bleed. Third, frankly, it's unsettling having someone you don't know breathing down your neck, looking at what you're doing, or worse yet, telling you what to do.
Where I work now, the policy is up to the individual doctor. I let the dads stay if they insist, but I ask them to stand in front of the mom and hold her hand, comfort her, keep her sitting still, etc.
4. Try to hold still as the epidural is being placed. Let me preface this by saying that I am the biggest pansy on earth when it comes to pain, as are most guys. I wouldn't last 10 minutes in labor. I joke with patients that if dads had the childbearing responsibilities, the human race would've died out thousands of years ago.
That being said, it is incredibly disconcerting for me (and dangerous for you) if you move while I have a large needle in your back, within an inch or so of your spinal cord. Bad things can happen. So try really, really, really hard not to move. Labor must hurt something awful, because women, even the most squeamish ones, eventually sit amazingly still if it means the difference between getting or not getting an epidural. Just gimme five more minutes and your pain will be so much better...
5. If you're at an academic medical center, don't ask an attending to do you your epidural. The falsely enlightened ones who would come to Northwestern when I was a resident would do this, and besides being annoying, it was barking up the wrong tree. By the time I was a senior resident, I had placed literally 400 epidurals, all in a four month span. Any of the attending physicians I was working with had placed...nowhere near that many. They're way too busy supervising and doing administrative tasks and are out of practice. With all due respect to my old attendings, if you must ask someone to place your epidural ask a senior resident, or if you're really savvy, an OB fellow if there are any. Generally, though, a good old junior resident will do the job just fine.
6. Unless you're trying to go without, get the epidural as soon as you can. I'm sure any OB reading this will have a fit, but I still think it's a good idea. Before, the wisdom was that getting an epidural before you were 4 centimeters dilated would slow labor and increase the risk of c-section. But several studies have shown (including one that was completed at Northwestern, by the way) that that is not the case. You'll be comfortable for longer, and should things go awry, the epidural is there for a c-section if needed.
7. The longer you wait, the harder it is to get the epidural. The reason is simple. As your cervical dilation increases and contractions get more intense, they hurt more and it's a lot harder to sit still when the epidural is being placed. Also the strength and intensity of the contractions then are such that it is difficult to get full and quick relief from the epidural. But there's a happy corollary to this one:
8. It's never too late to get the epidural. At least it's never too late from the anesthesiologist perspective. Again, if you can sit still, we can try to place it. I remember on one occasion as a resident where I was asked to place an epidural in a woman who was pushing. They were concerned she would need help delivering by forceps and didn't want her to be uncomfortable. So she stopped pushing, sat up for the epidural, and when she got it, kept on pushing. Amazing. Now if the OB doesn't want it for their own set of medical reasons, that's another story...
9. Don't expect a miracle. In some ways, epidural anesthesia is burdened by its own success. One woman tells another who tells another that her epidural was great, and then that woman comes in to deliver, expecting to do so without a hint of pain. Needless to say, that's simply not realistic. We as anesthesiologists can dose the epidural that way, making you so numb you can't feel anything. The problem is that you won't be able to move your legs, and that will make pushing difficult if not impossible and increase the chance of c-section or instrumented delivery. The OB doctors don't like it when we make patients that numb. Sometimes things like spinal anatomy or the position of the baby can cause issues with discomfort that even the best epidural can't completely fix. The ideal is to feel the pressure of the contractions, so that you can actively push, but without the pain that came with them before the epidural.
Epidurals: what could go wrong?
Like I said in my last post, the benefits of the epidural are obvious. Pain gone. Feel much better. (And, in the event of a change of plans requiring a c-section, it's easy to add more medicine to the epidural to make the woman numb enough to have a c-section comfortably and still be awake to see the baby born).
Now I'm not trying to be a big giant buzz kill, but it's my job, as an anesthesiologist, to think like a pessimist and be prepared for problems and complications. I don't expect them (and, fortunately, have had vanishingly few in my career so far), but just considering their possibilities every time I place a catheter is like my little ritual to ward off the bad vibes. Perhaps this knowledge can work for you in the same way. However, if you are someone who is scared witless (or something else rhyming with witless) by knowing too much, then read no further. My intent is not to frighten people out of getting epidurals but to help them enter the procedure realizing the extent of its invasiveness and the things that might (but honestly, probably won't) go wrong.
Just to be simple and organized, I put them in list form.
What could go wrong with your epidural?
1. Infection. That's why it's a sterile procedure, where we wash our hands beforehand, clean your back with sterile soap, then we put on sterile gloves to open a sterile epidural kit. We wear masks and surgical caps for good measure. Infection, fortunately, is incredibly rare nowadays. But the epidural catheter tip is within a centimeter of the spinal cord. If it's dirty, infection can happen, and needless to say, it's NOT a good place to be infected. That's why any anesthesiologist worth their salt takes sterile technique very, very seriously.
2. Bleeding. Again, bleeding is rare unless you have a condition, congenital or acquired, that predisposes you to bleeding. A woman who is suspected of being pre-eclamptic can have low platelet counts, ones this can change quickly. If that is the case, your anesthesiologist will want to see a recent platelet count before placing an epidural. In the rare cases bleeding occurs, it is usually secondary to the catheter being put it or taken out, in combination with some other intrinsic bleeding issue. Epidural bleeding is bad for obvious reasons - it can cause compression of the spinal cord and neurologic compromise. Did I mention how incredibly rare bleeding and infection are? In three years of training, during which about 28,000 deliveries occurred at my training program, I only know of one epidural abscess or bleed. And even there, it wasn't certain if the epidural caused the problem...
3. Nerve injury. This is even rarer than the first two complications, because the epidural by definition doesn't touch nerves or nerve roots. In a combined spinal/epidural, the spinal needle can graze a nerve root as it enters the dural sac, but that is rare and even when it happens, the needle is so small that it almost never causes even the most transient of symptoms.
4. Nerve palsy. This is totally different from direct nerve injury from anesthetic or a needle. Anesthesia plays an indirect role in this, however, though at times when I was a resident we were blamed more directly than we deserved. Nerve palsies, usually femoral or obturator nerve palsies, occur when the nerves from the low lumbar and sacral roots are compressed for a prolonged period of time by the fetal head. It is rare, but when it happens, the woman doesn't know it until afterwards because, of course, she was numb from the epidural as the nerve compression was occurring. I've also heard of numbness in the legs, feet, and lateral thighs from simply being in stirrups, especially if the woman pushed for a long time. Again, it's not a direct result of anesthesia, but the woman often doesn't know until after the epidural has worn off that she has a numbness in the area in question.
5. The finder needle gets pushed too far and enters the dura. This is the dreaded "wet-tap.". Simply put, this happens when, for whatever reason (difficult anatomy, patient movement, operator error and/or inexperience, etc.), the anesthesiologist pushes the large finder needle too far. Instead of stopping at the epidural space behind the dura, the needle gets pushed through the dura and into the sac of spinal fluid. This in and of itself is not a huge problem. The procedure is still sterile and infection is still rare, and the catheter can be placed and threaded at another level if needed. The problem is afterwards.
When the dural lining is pierced by a large needle like that, it can cause a severe headache afterwards. Classically, it is a positional headache. It is worst when sitting up, when the pain is usually in the occiput, back of the neck, and the forehead. It is thought that the hold in the dura causes a leakage of spinal fluid and a tension on the dural linings in the brain. The headache improves significantly when lying down. Within a week to 10 days, the headache almost always resolves on its own; the problem is that when a new mother is at home with an infant, being confined to bed, lying down, is just not an option. So this kind of headache (known as a postdural puncture headache) is treated proactively when it occurs, with IV fluids, caffeine intake, and oral analgesics. If those don't work, the anesthesiologist can be called in to do a procedure called an epidural blood patch, to close, as it were, the hole in the dura. The success rates with the blood patch are very high.
6. The epidural is difficult for the anesthesiologist to place. The first five things on this list are more serious; the next few are mostly inconveniences and annoyances. Getting an epidural requires sitting in a very uncomfortable position, slouched over with your lower back protruding out - very difficult to do with a full term uterus, not to mention a contraction every two or three minutes. When the poor woman is forced to sit in that position for a half hour or more, it can be tough on everyone. Unless there is a medical reason why the woman really should get an epidural, I'll let her choose if I'm struggling to place it. If I have been trying for a half hour to get an epidural, my telling her how great she'll feel later is sure to fall on deaf ears.
A lot of things can contribute to technical difficulties with epidurals, like abnormal bony anatomy (scoliosis, previous surgery, etc), but since the epidural is placed by feel, the biggest obstacle to epidural placement is...yes, obesity. You know those people who are so skinny you can see the bones in their back? Those people are easy to put epidurals in, because their landmarks are easy to see. If your back is covered with a lot of...um, adipose tissue, the bony landmarks of the back are hard (sometimes impossible) to feel, and placing the epidural can be a crapshoot. Oh sure, once in a while you'll find the thin patient with an amorphous, dough-like back, and the obese patient with easily palpable landmarks, but in general, if someone is obese, it greatly increases the chance of difficult epidural placement, which leads to the next two things on the list...
7. Your back is sore afterwards. My wife had her epidural put in by one of my old attendings. 1 pass with the needle and the epidural was in, and it worked great. Even in that total best-case scenario, she said her back felt sore and strange for several months afterwards, right in the spot where she got the epidural. If getting your epidural was difficult for the anesthesiologist for whatever reason and you were poked more than once, you'll probably be a little sore too.
8. The epidural just doesn't work right. All kinds of things fall into this category. The catheter could fall out at some point because it wasn't taped securely. The epidural makes you numb only on one side, or doesn't work at all. The anesthesiologist's soluton in some of those cases is to simply give more local anesthetic through the epidural. Sometimes that works. Sometimes it doesn't. In those situations where all else fails, the dilemma is the same; should you just make do, or is it worth it to have the anesthesiologist try to place it again? That's a call only you and your anesthesiologist can make.
This is just a partial list. I'm sure I missed a few ones, and there are some other crazy obscure things that I won't mention, but these are the big things to watch out for...
Now I'm not trying to be a big giant buzz kill, but it's my job, as an anesthesiologist, to think like a pessimist and be prepared for problems and complications. I don't expect them (and, fortunately, have had vanishingly few in my career so far), but just considering their possibilities every time I place a catheter is like my little ritual to ward off the bad vibes. Perhaps this knowledge can work for you in the same way. However, if you are someone who is scared witless (or something else rhyming with witless) by knowing too much, then read no further. My intent is not to frighten people out of getting epidurals but to help them enter the procedure realizing the extent of its invasiveness and the things that might (but honestly, probably won't) go wrong.
Just to be simple and organized, I put them in list form.
What could go wrong with your epidural?
1. Infection. That's why it's a sterile procedure, where we wash our hands beforehand, clean your back with sterile soap, then we put on sterile gloves to open a sterile epidural kit. We wear masks and surgical caps for good measure. Infection, fortunately, is incredibly rare nowadays. But the epidural catheter tip is within a centimeter of the spinal cord. If it's dirty, infection can happen, and needless to say, it's NOT a good place to be infected. That's why any anesthesiologist worth their salt takes sterile technique very, very seriously.
2. Bleeding. Again, bleeding is rare unless you have a condition, congenital or acquired, that predisposes you to bleeding. A woman who is suspected of being pre-eclamptic can have low platelet counts, ones this can change quickly. If that is the case, your anesthesiologist will want to see a recent platelet count before placing an epidural. In the rare cases bleeding occurs, it is usually secondary to the catheter being put it or taken out, in combination with some other intrinsic bleeding issue. Epidural bleeding is bad for obvious reasons - it can cause compression of the spinal cord and neurologic compromise. Did I mention how incredibly rare bleeding and infection are? In three years of training, during which about 28,000 deliveries occurred at my training program, I only know of one epidural abscess or bleed. And even there, it wasn't certain if the epidural caused the problem...
3. Nerve injury. This is even rarer than the first two complications, because the epidural by definition doesn't touch nerves or nerve roots. In a combined spinal/epidural, the spinal needle can graze a nerve root as it enters the dural sac, but that is rare and even when it happens, the needle is so small that it almost never causes even the most transient of symptoms.
4. Nerve palsy. This is totally different from direct nerve injury from anesthetic or a needle. Anesthesia plays an indirect role in this, however, though at times when I was a resident we were blamed more directly than we deserved. Nerve palsies, usually femoral or obturator nerve palsies, occur when the nerves from the low lumbar and sacral roots are compressed for a prolonged period of time by the fetal head. It is rare, but when it happens, the woman doesn't know it until afterwards because, of course, she was numb from the epidural as the nerve compression was occurring. I've also heard of numbness in the legs, feet, and lateral thighs from simply being in stirrups, especially if the woman pushed for a long time. Again, it's not a direct result of anesthesia, but the woman often doesn't know until after the epidural has worn off that she has a numbness in the area in question.
5. The finder needle gets pushed too far and enters the dura. This is the dreaded "wet-tap.". Simply put, this happens when, for whatever reason (difficult anatomy, patient movement, operator error and/or inexperience, etc.), the anesthesiologist pushes the large finder needle too far. Instead of stopping at the epidural space behind the dura, the needle gets pushed through the dura and into the sac of spinal fluid. This in and of itself is not a huge problem. The procedure is still sterile and infection is still rare, and the catheter can be placed and threaded at another level if needed. The problem is afterwards.
When the dural lining is pierced by a large needle like that, it can cause a severe headache afterwards. Classically, it is a positional headache. It is worst when sitting up, when the pain is usually in the occiput, back of the neck, and the forehead. It is thought that the hold in the dura causes a leakage of spinal fluid and a tension on the dural linings in the brain. The headache improves significantly when lying down. Within a week to 10 days, the headache almost always resolves on its own; the problem is that when a new mother is at home with an infant, being confined to bed, lying down, is just not an option. So this kind of headache (known as a postdural puncture headache) is treated proactively when it occurs, with IV fluids, caffeine intake, and oral analgesics. If those don't work, the anesthesiologist can be called in to do a procedure called an epidural blood patch, to close, as it were, the hole in the dura. The success rates with the blood patch are very high.
6. The epidural is difficult for the anesthesiologist to place. The first five things on this list are more serious; the next few are mostly inconveniences and annoyances. Getting an epidural requires sitting in a very uncomfortable position, slouched over with your lower back protruding out - very difficult to do with a full term uterus, not to mention a contraction every two or three minutes. When the poor woman is forced to sit in that position for a half hour or more, it can be tough on everyone. Unless there is a medical reason why the woman really should get an epidural, I'll let her choose if I'm struggling to place it. If I have been trying for a half hour to get an epidural, my telling her how great she'll feel later is sure to fall on deaf ears.
A lot of things can contribute to technical difficulties with epidurals, like abnormal bony anatomy (scoliosis, previous surgery, etc), but since the epidural is placed by feel, the biggest obstacle to epidural placement is...yes, obesity. You know those people who are so skinny you can see the bones in their back? Those people are easy to put epidurals in, because their landmarks are easy to see. If your back is covered with a lot of...um, adipose tissue, the bony landmarks of the back are hard (sometimes impossible) to feel, and placing the epidural can be a crapshoot. Oh sure, once in a while you'll find the thin patient with an amorphous, dough-like back, and the obese patient with easily palpable landmarks, but in general, if someone is obese, it greatly increases the chance of difficult epidural placement, which leads to the next two things on the list...
7. Your back is sore afterwards. My wife had her epidural put in by one of my old attendings. 1 pass with the needle and the epidural was in, and it worked great. Even in that total best-case scenario, she said her back felt sore and strange for several months afterwards, right in the spot where she got the epidural. If getting your epidural was difficult for the anesthesiologist for whatever reason and you were poked more than once, you'll probably be a little sore too.
8. The epidural just doesn't work right. All kinds of things fall into this category. The catheter could fall out at some point because it wasn't taped securely. The epidural makes you numb only on one side, or doesn't work at all. The anesthesiologist's soluton in some of those cases is to simply give more local anesthetic through the epidural. Sometimes that works. Sometimes it doesn't. In those situations where all else fails, the dilemma is the same; should you just make do, or is it worth it to have the anesthesiologist try to place it again? That's a call only you and your anesthesiologist can make.
This is just a partial list. I'm sure I missed a few ones, and there are some other crazy obscure things that I won't mention, but these are the big things to watch out for...
Epidurals: What's going on back there?
As promised, I wanted to talk a bit about the technical aspects of epidural anesthesia. At some point I'll try to post pictures; they'll help quite a bit.
First a quick anatomy lesson is needed. So you have a brain and a spinal cord, as well as nerve roots that come out of each side of the spinal cord, between each of the 24 vertebrae that we all possess. This constitutes your central nervous system (CNS). The whole CNS is bathed in cerebrospinal fluid that is itself contained in a bag, as it were. That bag, that lining of the spinal cord and brain, is the dura mater, or just dura for short.
As I said before, the spinal cord has nerve roots that come off on each side at each vertebral level, all the way down to the sacrum, the middle bone of the pelvis. The spinal cord itself, though, doesn't extend all the way down to the pelvis, though; it stops at the L1 or L2 vertebra in most people, ie halfway down your lower back. The dural sac of fluid that envelops then whole CNS extends much further down. So past your L2 vertebra, the dural sac of fluid contains nothing but spinal fluid and nerve roots, just floating freely therein.
What's the point? The point is that when I (or any other anesthesia practitioner) is putting in an epidural, I put it in very low in the back, lower than the point where the spinal cord actually ends. The usual spot is between the 3rd and 4th lumbar vertebrae, or L3-4 for short. Sometimes due to technical considerations, I will go one level higher or lower, but never higher than L2. First of all, obviously, it's much safer to put in the epidural lower in the back, and second, the pain fibers activated during labor come from a wide range of nerve roots, and the L3-4 location is well in the middle of that.
To understand the epidural further we need to look at the name of the procedure - epi-dural. The prefix "epi" means "on" or "against". The epidural catheter place by the anesthesiologist does not rest on the spinal cord; instead it rests against the dural sac that surrounds the spinal cord. So it never actually touches nerves, and there is an added element of safety because of that.
To get to the epidural space just outside the dural sac requires using a big needle called a Tuohy needle, which is inserted (after numbing the skin with local anesthetic), in between the lumbar vertebrae, usually the L3-4 space as I said before. Then, once the skin is numb and the needle is in place in the back, I advance it slowly, while I have it hooked up to a syringe filled with air. What's this for? Well, the spaces between the vertebrae are populated by a number of very firm ligaments, and these ligaments help maintain the integrity of the spine. For the anesthesiologist, they provide resistance when the air filled syringe is pushed against them. As the needle is pushed inward, the resistance is felt when pushing on the air-filled syringe - until the tip of the needle enters the area right outside the dura. That's right, it's the epidural space. I guess technically anatomists don't consider it a "space" because there's really nothing in there except a few veins. This is key, because while I'm pushing on the air-filled syringe and advancing my needle, that epidural "space" feels completely different. Suddenly there's no resistance, and that's how I tell I'm in the right spot.
At that point that's where I can do one of two things, either placing the epidural catheter through the needle, or sticking a long, thin needle through the thicker needle to pierce the dura. The latter is called a combined spinal-epidural, which is how I was trained. Through this tiny needle, I put a small dose of narcotic and local anesthetic into the sac surrounding the CNS. Then I withdraw the small needle and thread the catheter through the larger Tuohy needle. The dural hole created by the spinal needle is small enough that the epidural catheter won't go through it.
The epidural doesn't go that far into the back. Usually it is about 4 or 5 centimeters deep to get to the epidural space, then the catheter is inserted another 4 to 5 centimeters into the space. So a total of 8 to 10 centimeters of catheter is left inside for the duration of labor. It's deep enough that it freaks some people out when I pull the catheter later and they see how deep it was, but not terribly deep.
The epidural catheter is hollow and wire reinforced, which is important because it means medication can be give through it, namely local anesthetic which can keep the woman comfortable throughout her labor and delivery. After giving a small dose of local anesthetic mixed with epinephrine through the catheter to make sure it hasn't inadvertently entered a vein (appropriately, this is called a "test dose"), the catheter is attached to a small pump that administers a continuous flow of local anesthetic up to and through the time the woman delivers.
So that's it. If things go smoothly, from the time I infiltrate the skin with local anesthesia to the time I thread the epidural catheter can be as short as a couple of minutes. Others may be even faster. Speed is key, not just because the woman is in such pain, but going fast makes it possible to (try to) time the epidural placement in between contractions. Now if there are technical difficulties, then things can take longer. A lot longer. That leads me to my next topic. Everyone knows the benefits to getting the epidural; how about the risks? It is empirically a very safe procedure, but it is still worthwhile to think about what could go wrong...
First a quick anatomy lesson is needed. So you have a brain and a spinal cord, as well as nerve roots that come out of each side of the spinal cord, between each of the 24 vertebrae that we all possess. This constitutes your central nervous system (CNS). The whole CNS is bathed in cerebrospinal fluid that is itself contained in a bag, as it were. That bag, that lining of the spinal cord and brain, is the dura mater, or just dura for short.
As I said before, the spinal cord has nerve roots that come off on each side at each vertebral level, all the way down to the sacrum, the middle bone of the pelvis. The spinal cord itself, though, doesn't extend all the way down to the pelvis, though; it stops at the L1 or L2 vertebra in most people, ie halfway down your lower back. The dural sac of fluid that envelops then whole CNS extends much further down. So past your L2 vertebra, the dural sac of fluid contains nothing but spinal fluid and nerve roots, just floating freely therein.
What's the point? The point is that when I (or any other anesthesia practitioner) is putting in an epidural, I put it in very low in the back, lower than the point where the spinal cord actually ends. The usual spot is between the 3rd and 4th lumbar vertebrae, or L3-4 for short. Sometimes due to technical considerations, I will go one level higher or lower, but never higher than L2. First of all, obviously, it's much safer to put in the epidural lower in the back, and second, the pain fibers activated during labor come from a wide range of nerve roots, and the L3-4 location is well in the middle of that.
To understand the epidural further we need to look at the name of the procedure - epi-dural. The prefix "epi" means "on" or "against". The epidural catheter place by the anesthesiologist does not rest on the spinal cord; instead it rests against the dural sac that surrounds the spinal cord. So it never actually touches nerves, and there is an added element of safety because of that.
To get to the epidural space just outside the dural sac requires using a big needle called a Tuohy needle, which is inserted (after numbing the skin with local anesthetic), in between the lumbar vertebrae, usually the L3-4 space as I said before. Then, once the skin is numb and the needle is in place in the back, I advance it slowly, while I have it hooked up to a syringe filled with air. What's this for? Well, the spaces between the vertebrae are populated by a number of very firm ligaments, and these ligaments help maintain the integrity of the spine. For the anesthesiologist, they provide resistance when the air filled syringe is pushed against them. As the needle is pushed inward, the resistance is felt when pushing on the air-filled syringe - until the tip of the needle enters the area right outside the dura. That's right, it's the epidural space. I guess technically anatomists don't consider it a "space" because there's really nothing in there except a few veins. This is key, because while I'm pushing on the air-filled syringe and advancing my needle, that epidural "space" feels completely different. Suddenly there's no resistance, and that's how I tell I'm in the right spot.
At that point that's where I can do one of two things, either placing the epidural catheter through the needle, or sticking a long, thin needle through the thicker needle to pierce the dura. The latter is called a combined spinal-epidural, which is how I was trained. Through this tiny needle, I put a small dose of narcotic and local anesthetic into the sac surrounding the CNS. Then I withdraw the small needle and thread the catheter through the larger Tuohy needle. The dural hole created by the spinal needle is small enough that the epidural catheter won't go through it.
The epidural doesn't go that far into the back. Usually it is about 4 or 5 centimeters deep to get to the epidural space, then the catheter is inserted another 4 to 5 centimeters into the space. So a total of 8 to 10 centimeters of catheter is left inside for the duration of labor. It's deep enough that it freaks some people out when I pull the catheter later and they see how deep it was, but not terribly deep.
The epidural catheter is hollow and wire reinforced, which is important because it means medication can be give through it, namely local anesthetic which can keep the woman comfortable throughout her labor and delivery. After giving a small dose of local anesthetic mixed with epinephrine through the catheter to make sure it hasn't inadvertently entered a vein (appropriately, this is called a "test dose"), the catheter is attached to a small pump that administers a continuous flow of local anesthetic up to and through the time the woman delivers.
So that's it. If things go smoothly, from the time I infiltrate the skin with local anesthesia to the time I thread the epidural catheter can be as short as a couple of minutes. Others may be even faster. Speed is key, not just because the woman is in such pain, but going fast makes it possible to (try to) time the epidural placement in between contractions. Now if there are technical difficulties, then things can take longer. A lot longer. That leads me to my next topic. Everyone knows the benefits to getting the epidural; how about the risks? It is empirically a very safe procedure, but it is still worthwhile to think about what could go wrong...
The universal anesthesia experience...
Now that I have talked about delving into the whole process of general anesthesia, I want to begin by talking about an anesthetic experience most mothers in America have experienced, one where they are very much awake. That, of course, is the epidural, which for most young healthy women is (hopefully, for their sake) their sole exposure to the field of anesthesia. Being that the procedure is performed at such an intense point in a woman's life, both physically and emotionally, you can ask pretty much any woman who has had one about it, and they can probably tell you in exquisite detail about how it went.
"It worked great."
"It only worked on one side."
"The anesthesiologist got it in two minutes."
"It was 3:30 in the morning, my water had just broken, and I was 5 centimeters dilated. I was dying. It took the anesthesiologist a half hour to get it, and he had to try twice." Like in any emotionally charged moment, the details stick out clearly even years later.
Whatever the case, most of the women who got one end saying something along the lines of "it was awesome".
Surprisingly, to me anyway, not a lot of male anesthesioogists I have worked with in the past like OB anesthesia. I'm not sure why, because I enjoy it a lot. My wife and I have a son who was born at the end of my residency under some crazy circumstances, but that's a whole other story. I mention it because I remember how excited and, well, alive I felt around the time our son was born. It ranks as one of the most memorable days of my life, and for most people I see in the OB ward, it is that kind of day for them too. It's a really cool thing, in my opinion, to be a part of that.
Another reason I like OB anesthesia so much is that I'm impatient. Let me explain. When I walk into the room of a woman in labor, she's absolutely miserable, writhing in agony, cursing, screaming, grimacing, or all of those. If everything goes well, twenty minutes later, when I walk out of the the room, she's happy, smiling, comfortable, and really, really, really grateful. What's better than that? In my world of anesthesia, not much. It's immediate gratification in its purest form, and I have done something good for someone as well.
But just in case I start feeling a bit too good about myself and my epidural abilities, I remember this: my role in the whole childbirth process is not medically necessary. Of course, any woman who can remember how awful labor was might disagree, but the fact of the matter is that women delivered babies for thousands of years before epidural anesthesia. At Northwestern, where I trained, 90% of the women, conservatively, got epidurals. A lot of things are factored into that, such as the wishes of the obstetrician, and the patient population. We had a lot of well-to-do patients who pretty much expected the epidural to be a standard part of the birth experience. That was its own set of issues, good and bad, and that's a story for another time.
In future blogs I'm going to get into a little bit of the technical stuff about epidurals, (without trying to get too boring), and then I'll just give a list of useful advice for moms-to-be who are considering getting an epidural.
"It worked great."
"It only worked on one side."
"The anesthesiologist got it in two minutes."
"It was 3:30 in the morning, my water had just broken, and I was 5 centimeters dilated. I was dying. It took the anesthesiologist a half hour to get it, and he had to try twice." Like in any emotionally charged moment, the details stick out clearly even years later.
Whatever the case, most of the women who got one end saying something along the lines of "it was awesome".
Surprisingly, to me anyway, not a lot of male anesthesioogists I have worked with in the past like OB anesthesia. I'm not sure why, because I enjoy it a lot. My wife and I have a son who was born at the end of my residency under some crazy circumstances, but that's a whole other story. I mention it because I remember how excited and, well, alive I felt around the time our son was born. It ranks as one of the most memorable days of my life, and for most people I see in the OB ward, it is that kind of day for them too. It's a really cool thing, in my opinion, to be a part of that.
Another reason I like OB anesthesia so much is that I'm impatient. Let me explain. When I walk into the room of a woman in labor, she's absolutely miserable, writhing in agony, cursing, screaming, grimacing, or all of those. If everything goes well, twenty minutes later, when I walk out of the the room, she's happy, smiling, comfortable, and really, really, really grateful. What's better than that? In my world of anesthesia, not much. It's immediate gratification in its purest form, and I have done something good for someone as well.
But just in case I start feeling a bit too good about myself and my epidural abilities, I remember this: my role in the whole childbirth process is not medically necessary. Of course, any woman who can remember how awful labor was might disagree, but the fact of the matter is that women delivered babies for thousands of years before epidural anesthesia. At Northwestern, where I trained, 90% of the women, conservatively, got epidurals. A lot of things are factored into that, such as the wishes of the obstetrician, and the patient population. We had a lot of well-to-do patients who pretty much expected the epidural to be a standard part of the birth experience. That was its own set of issues, good and bad, and that's a story for another time.
In future blogs I'm going to get into a little bit of the technical stuff about epidurals, (without trying to get too boring), and then I'll just give a list of useful advice for moms-to-be who are considering getting an epidural.
Hello and welcome
Good morning all,
My name is Ben and I am an anesthesiologist living and working in the Chicago area. My job, by nature, is enshrouded in mystery. Like all doctors, I have done many year of training and have steadfastly dedicated myself to practicing medicine in the best way I know how. Unlike other doctors, though, my patients have to take me at my word when I tell them that, because they're sleeping while I am taking care of them.
So what is it that I (and 46,000 other anesthesiologists nationwide, not to mention thousands of CRNAs) do while you the patient are sleeping? Millions of surgeries, and thus millions of anesthetics, are done in the United States each year, and the overwhelming majority of them do just fine. General anesthesia is truly one of the most amazing advances in modern medicine, allowing for painless surgery and the endless array of invasive procedures that doctors are now capable of performing. Once quite dangerous for even the healthy patients, time and technology have sharpened and refined it considerably to the point that general anesthesia, even on the sickest patients, is a very safe endeavor.
In some ways, though, anesthesia, like all of modern medicine, has become a victim of its own success, so to speak. Their record of safety, especially recently, has become so good that the general public takes for granted how fascinatingly complex - and dangerous - even the most "routine" anesthetic can be. Two years ago, when Michael Jackson died as a result of the misuse of the common anesthetic drug propofol, this danger raised its ugly head, and with tragic consequences. The buzz of publicity that followed was particularly revealing to me in that it showed how little people really understood about anesthesia and what I do for a living. Two years later, I encounter that misunderstanding every day, in every place - comments I hear from patients, sound bites on TV and radio.
Even many of the surgeons I work with don't know a lot about what I'm doing back there on the other side of the surgical drapes. As long as the patient is safe, immobile during surgery, and wakes up at the end, that's all that matters to them. That's no knock on the surgeons; their focus is on their operation, and conversely, I don't pretend to know how to perform any of the operations I am privileged to participate in on a daily basis. If they are focused too much on me, they can't perform their best operation, and it isn't good for anybody.
The biggest reason I have started this blog is to help demystify exactly what goes on when the patient is asleep during surgery. I won't give a step-by-step guide on how to give anesthesia; it takes years of study and training to accomplish that. What I can do is provide an insider's perspective on the complex process that is anesthesiology. Even the simplest general anesthetic involves bringing a patient perilously close to death, controlling all aspects of their physiology while they sleep, all the while maintaining their immobility, minimizing their discomfort, and ensuring their amnesia of the operation. It is a task I, and thousands of other anesthesia providers like me, take seriously. Over the course of this blog, I hope to shed some light on how and why we do things, and in doing so, I can hopefully unmask some of the mystery - and allay most of the fears - that patients feel before undergoing anesthesia.
My name is Ben and I am an anesthesiologist living and working in the Chicago area. My job, by nature, is enshrouded in mystery. Like all doctors, I have done many year of training and have steadfastly dedicated myself to practicing medicine in the best way I know how. Unlike other doctors, though, my patients have to take me at my word when I tell them that, because they're sleeping while I am taking care of them.
So what is it that I (and 46,000 other anesthesiologists nationwide, not to mention thousands of CRNAs) do while you the patient are sleeping? Millions of surgeries, and thus millions of anesthetics, are done in the United States each year, and the overwhelming majority of them do just fine. General anesthesia is truly one of the most amazing advances in modern medicine, allowing for painless surgery and the endless array of invasive procedures that doctors are now capable of performing. Once quite dangerous for even the healthy patients, time and technology have sharpened and refined it considerably to the point that general anesthesia, even on the sickest patients, is a very safe endeavor.
In some ways, though, anesthesia, like all of modern medicine, has become a victim of its own success, so to speak. Their record of safety, especially recently, has become so good that the general public takes for granted how fascinatingly complex - and dangerous - even the most "routine" anesthetic can be. Two years ago, when Michael Jackson died as a result of the misuse of the common anesthetic drug propofol, this danger raised its ugly head, and with tragic consequences. The buzz of publicity that followed was particularly revealing to me in that it showed how little people really understood about anesthesia and what I do for a living. Two years later, I encounter that misunderstanding every day, in every place - comments I hear from patients, sound bites on TV and radio.
Even many of the surgeons I work with don't know a lot about what I'm doing back there on the other side of the surgical drapes. As long as the patient is safe, immobile during surgery, and wakes up at the end, that's all that matters to them. That's no knock on the surgeons; their focus is on their operation, and conversely, I don't pretend to know how to perform any of the operations I am privileged to participate in on a daily basis. If they are focused too much on me, they can't perform their best operation, and it isn't good for anybody.
The biggest reason I have started this blog is to help demystify exactly what goes on when the patient is asleep during surgery. I won't give a step-by-step guide on how to give anesthesia; it takes years of study and training to accomplish that. What I can do is provide an insider's perspective on the complex process that is anesthesiology. Even the simplest general anesthetic involves bringing a patient perilously close to death, controlling all aspects of their physiology while they sleep, all the while maintaining their immobility, minimizing their discomfort, and ensuring their amnesia of the operation. It is a task I, and thousands of other anesthesia providers like me, take seriously. Over the course of this blog, I hope to shed some light on how and why we do things, and in doing so, I can hopefully unmask some of the mystery - and allay most of the fears - that patients feel before undergoing anesthesia.
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