ICD-10 for Obstetric Anesthesiology: What You Need to Know

  • Zakowski, Mark, MD
| Dec 15, 2015

Mark_ZakowskiWhimper or boom? It’s still too early to tell. After years of delayed implementation, ICD-10 (International Classification of Diseases) has become mandatory for use in the United States as of October 1, 2015.  While ICD-10 was created in 1990, and first used by World Health Organization members in 1994, most countries around the world have been using ICD-10 for several years. The United States has been using the system for mortality reporting since 1999.

magSo what’s all the fuss about?  The number of codes in America’s ICD-10-CM has exploded from about 12,000 in ICD-9 to 69,000—more than any human can memorize. The actual code reported has changed from a 5-digit code (ICD-9 format) to a 7-digit code.  Fortunately, there is a system to this apparent madness.  The first three digits identify the general medical category, the second three code for the etiology, anatomic site, and severity of disease, and the seventh digit is an extension, providing additional information, if necessary. 

The intent is to use coding to follow population health, trauma and epidemiology.  Newly required information in ICD-10 is laterality, (left, right, bilateral, unspecified), which by itself adds about 25,000 variations in coding. The award for most complex coding goes to orthopedics, which goes as far as describing the multiple types of fractures for each bone. Fortunately, obstetric anesthesia coding is much simpler.

The other major category required in ICD-10 is the type of encounter. Initial encounter means the problem is being actively treated; in anesthesiology, that usually means the patient is having surgery or a procedure. Note that for surgery, the initial pre-operative office visit is NOT the initial treatment, but the surgery/procedure is. The next phase is the subsequent encounter, intended as the recovery phase of the illness/treatment. The third and last type of encounter is sequelae, or complications, which can stem from the treatment. There are additional codes for complications from anesthesia.

The physician anesthesiologist needs to document the patient’s condition(s), reasons for surgery, trauma (rare in OB), laterality (uncommon in OB), complications, and encounter type. The professional coder will translate what you document into the correct ICD-10 code, but can ONLY code from what’s in the medical record.

The best places for anesthesiologists to document are in the pre-operative assessment, anesthesia record, or post-operative note, with the diagnosis reflecting the correct post-op diagnosis, not the pre-op diagnosis. It is best to copy the surgeon’s ICD-10 coding if you can.  The easier you make it for your coders to find the required information, the less time they will spend on a claim (hard cost of billing), the more accurate the information will be (real cost of denials/claims reprocessing), and there will be fewer delays in collections (accounts receivable).

With respect to obstetric anesthesia, the first three digits will start with an O, indicating obstetric, or a P, indicating newborn pediatric. The other major classification categories needed for coding that should be included and clear in your preoperative assessment note are timing (pregnancy, childbirth, puerperium) and trimester (1, 2, or 3).  












Two of the most common events coded in obstetric anesthesia include term, uncomplicated vaginal delivery (O80.xxx.x) and term cesarean, no medical indication (O82.xxx.x). Preterm labor and delivery must specify when the preterm labor occurred and when the actual delivery occurred – e.g. preterm labor second trimester with preterm delivery third trimester (O60.13x.x).  These examples are not intended for your memorization, but rather to reinforce the type of information you need to include in your notes for proper coding. Remember: incorrect coding equals claims denial!

Complications of anesthesia may occur from the following: general anesthesia, regional anesthesia, local anesthetic injection, sedation or analgesics. Of course, some of these may not even involve an anesthesiologist; the data is collected and intended for big data epidemiology. Complications of anesthesia affecting the newborn (P01.0) include: being affected by maternal anesthesia and analgesia during pregnancy, labor, and delivery, or being affected by maternal opiates and tranquilizers during labor and delivery.

Complications of obstetric anesthesia are coded by pregnancy (O29), childbirth (O74) or puerperium (O94).  Events beyond the 6-week puerperium are coded as non-obstetric.  Complications of anesthesia are defined in ICD-10 as pulmonary, cardiac, CNS, toxic reaction to local anesthetic, spinal epidural, post-dural puncture headache (PDPH), other complications of spinal epidural, failure or difficult intubation of anesthesia, other complications of anesthesia, and unspecified complications of anesthesia.


O74 Complications of anesthesia during childbirth (labor and delivery)

O74.0 Pulmonary – aspiration

O74.1 Other pulmonary

O74.2 Cardiac

O74.3 CNS

O74.4 Toxic reaction local anesthetic

O74.5 Spinal or epidural PDPH

O74.6 Other complication spinal / epidural

O74.7 Failed or difficult intubation for anesthesia

O74.8x Other complications anesthesia

O74.9 Unspecified complication of anesthesia

So, what other medical information do you need to add to your medical record to help ensure correct coding?  Take a deep breath and relax.  Most of the list makes sense, and we already do the others anyway. Be sure to add the following information that’s newly required in ICD-10:

  • Trimester (can be gestational age)
  • If multiple births, specify which baby had the problem (e.g. IUGR twin B)
  • Breech (list type - frank, footling, complete)
  • Diabetes (type, trimester occurred)
  • Previa (with or without hemorrhage)
  • Preeclampsia (mild, severe, HELLP)
  • Gestational hypertension (trimester first occurred)
  • Cesarean (no medical indication of 'elective,’ prior myomectomy/repeat uterine scar, or OB medical indication for cesarean)
  • Major repairs (third or fourth degree laceration)
  • Laterality of complication
  • Forceps/vacuum use
  • Laterality of additional procedure (e.g. right ovarian cyst). 

Medical information that is now required for ALL patients (obstetric and non-obstetric) includes alcohol use, tobacco use or exposure to tobacco smoke for any pulmonary condition (e.g. asthma, pneumonia, specifics of respiratory failure (hypoxia, hypercarbia), and hypertension (list heart or kidney involvement). 

embraceNow for the good news:  in a joint letter by CMS/AMA dated July 6, 2015, Medicare (does not apply to Medicaid or commercial carriers) will allow a one-year ‘flexibility’ on ICD-10 coding. This means they won’t issue a denial solely on ICD-10 coding if the code is mostly correct (within the same family of codes, with only the last digit(s) incorrect).   

With some education and a little more documentation details, your ICD-10 implementation should go relatively well. Sounds a little like Back to the Future!


  1. www.RoadTo10.org (CMS website on ICD-10)
  2. View the recorded webinar on ICD-10 by ASA Committee on Economics Chair Marc Leib, MD, JD and ASA Director of Payment and Practice Management Sharon Merrick, MS, CCS-P

Disclaimer:  This is an educational article written by a physician, with no expertise or degrees in coding.  Consult your own attorney, coder, or practice manager!

Leave a comment