SA first developed and approved the “Practice Guidelines for Obstetrical Anesthesia” in October 1998.¹ An updated document was approved in October 2006. So what’s new since 1998?

The guidelines now recommend examination of the airway, heart and lungs, consistent with the ASA “Practice Advisory on Preanesthesia Evaluation.” The Task Force on Practice Guidelines for Obstetric Anesthesia concluded that if we want to be recognized as physicians rather than technicians, obstetric patients should not receive a different standard of care than those in the main operating room. During forums an anesthesiologist who frequently serves as an expert witness in medical liability cases noted that family members often comment in depositions that the anesthesiologist never examined their loved one prior to block placement. Such observations may be detrimental to the defendant’s case.

Another addition to the guidelines is a stronger statement reinforcing communication between anesthesiology and obstetric services. Specifically the document states:

“Recognition of significant anesthetic or obstetric risk factors should encourage consultation between the obstetrician and the anesthesiologist. A communication system should be in place to encourage early and ongoing contact between obstetric providers, anesthesiologists, and other members of the multidisciplinary team.”

This statement supports the team training approach being studied in several medical venues.

A controversial area was balancing cost-effectiveness, utilization and immediate availability of blood bank resources in an unexpected emergency. The task force found that even among obstetric anesthesiologists who practice in tertiary care centers, there was no consensus to obtain routinely a “clot to hold” or other type of blood sample. Survey results from consultants and ASA members were equally divided, although they tended to agree that “all parturients should have an intrapartum blood sample sent to the blood bank to reduce maternal complications.” The recommendation states that type and screen or cross-match should be ordered on an individual basis based on risk factors and “local institutional policies.”

Nothing-by-mouth (NPO) guidelines in the section on “Aspiration Prevention” are largely unchanged. The ASA “Practice Guidelines for Preoperative Fasting,” however, is now referenced repeatedly to explain the six- to eight-hour range of NPO times for solids. The longer time interval applies to fatty foods that do not empty as quickly. Instead of specifying six or eight hours, task force members and consultants chose to keep the range for flexibility. A section on pharmacologic agents for aspiration prophylaxis was added to encourage practitioners to consider their use, although the literature could only support decreasing gastric acidity, not a reduction in maternal complications.

Finally, there is adequate literature to perform meta-analytic comparisons on timing of neuraxial analgesia. The new recommendation states:

“Neuraxial analgesia should not be withheld on the basis of achieving an arbitrary cervical dilation, and should be offered on an individualized basis. Patients should be reassured that the use of neuraxial analgesia does not increase the incidence of cesarean delivery.”²

How far we have come in the last 10 years! Early placement of neuraxial catheters for high-risk patients (e.g., twin gestation, difficult airway or obesity) also is encouraged, even prior to a request for labor analgesia. Neuraxial techniques without motor block are emphasized as well as availability of treatments for complications. A new recommendation on patient-controlled epidural analgesia states that it is effective, flexible and may be preferable to infusion techniques, reducing anesthetic interventions and dosages of local anesthetics with or without a basal infusion rate.

The task force added an important statement about the priority of care for parturients, stating:

“Equipment, facilities, and support personnel available in the labor and delivery operating suite should be comparable to those available in the main operating suite.”

In our own hospitals, haven’t we all fought for better equipment or coverage for labor and delivery equivalent to the main operating rooms?

In addition to a comparison of anesthetic techniques for cesarean delivery, the new document also contains recommendations on fluid preloading (beneficial but not mandatory), use of phenylephrine as an alternative for treating hypotension and a preference for neuraxial opioid administration for postoperative analgesia, when possible. Recommendations for postpartum tubal ligation emphasize compliance with oral intake guidelines and consideration of aspiration prophylaxis. Neuraxial techniques are preferred, noting higher failure rates of epidural catheters used for labor. Timing of the procedure should not compromise other aspects of patient care for labor and delivery.

There are new recommendations for “Management of Obstetric and Anesthetic Emergencies” that include consideration of cell salvage in cases of intractable hemorrhage. Consistent with the ASA “Practice Guidelines for Management of the Difficult Airway,”³ a qualitative carbon dioxide detector should be readily available (e.g., outside the operating rooms). Laryngeal or supraglottic airway devices may be used when intubation and ventilation are difficult. A surgical airway should be performed when a patient cannot be ventilated or awakened. The 2005 American Heart Association guidelines for cardiac arrest in pregnancy are referenced, with a reminder that the obstetrics team should perform a hysterotomy and delivery within four minutes of cardiac arrest to improve maternal resuscitation.

While developing the guidelines, task force members were asked by the ASA Committee on Performance and Outcomes Measurement to consider whether a pay-for-performance (P4P) measure could be recommended from their literature review and the consultant and member surveys. The Centers for Medicare & Medicaid Services has mandated the transition toward reimbursement based on predetermined performance standards. Regardless of our thoughts about the process, we should determine our performance standards rather than waiting for those mandated by a governmental agency. ASA has been actively searching for evidence-based measures that improve patient outcome and are under the anesthesiologist’s control (unlike preoperative administration of antibiotics, for example).

On the basis of this document, ASA has recommended its P4P item, the use of pencil-point spinal needles instead of cutting-bevel needles to reduce the frequency of postdural puncture headache in obstetric patients. This item is evidence-based and supported by both consultants and ASA members. Evidence for this item and survey results related to it will appear in the April 2007 issue of Anesthesiology.

Developing practice guidelines helps to identify areas where further research is needed; areas where evidence is lacking and practices are based on opinion. There are many areas in obstetric anesthesiology where our patients will benefit from implementation and publication of well-designed studies so that we will soon practice evidence-based medicine predominantly.

References:
1. ASA Task Force on Practice Guidelines for Obstetrical Anesthesia. Practice Guidelines for Obstetrical Anesthesia. Anesthesiology. 1999; 90:600-611.
2. American College of Obstetricians and Gynecologists Committee on Obstetric Practice. Analgesia and cesarean delivery rates. Obstet Gynecol. 2006; 107:1487-1488.
3. ASA Task Force on Practice Guidelines for Management of the Difficult Airway. Practice Guidelines for Management of the Difficult Airway. Anesthesiology. 2003; 98:1269-1277.

Joy L. Hawkins, M.D., is Professor of Anesthesiology, University of Colorado School of Medicine and Director of Obstetric Anesthesia, University of Colorado Hospital, Denver, Colorado.