Why Are Laboring Patients Kept NPO?
Laboring patients are traditionally kept NPO (nil per os) primarily due to concerns about aspiration risk during potential emergency anesthesia, though current evidence suggests this practice should be more flexible and individualized based on risk factors.
Traditional Rationale for NPO Status
The primary reason for keeping laboring patients NPO has historically been to reduce the risk of aspiration of gastric contents if emergency general anesthesia becomes necessary. This practice stems from concerns that:
- Labor may progress to emergency cesarean delivery requiring general anesthesia
- Pregnancy itself delays gastric emptying
- Pain and stress during labor may further slow gastric motility
- Aspiration pneumonitis can be a serious complication if it occurs
Current Evidence and Guidelines
The American Society of Anesthesiologists (ASA) guidelines provide important context:
- Clear fluids can be safely consumed up to 2 hours before anesthesia 1
- Light meals can be consumed up to 6 hours before anesthesia 1
- For laboring patients, the ASA notes that "solid foods should be avoided in laboring patients" 1
However, the Enhanced Recovery After Surgery (ERAS) Society recommends:
- "Free intake of clear fluids up to 2 hours and a light meal until 6 hours before induction of anesthesia is recommended unless specific contraindications exist" 1
Risk-Based Approach
Current evidence supports a more nuanced approach to NPO status during labor:
- Low-risk patients: May be allowed clear liquids during labor
- Higher-risk patients: More restrictive NPO policies may be appropriate for patients with:
- Morbid obesity
- Diabetes mellitus
- Difficult airway
- Increased risk for operative delivery (e.g., non-reassuring fetal heart rate pattern) 1
Impact of NPO Status
Prolonged NPO status during labor can lead to:
- Maternal dehydration
- Electrolyte abnormalities
- Patient dissatisfaction
- Increased anxiety 1
- Potential nutritional compromise if prolonged 2
Practical Management
Based on current guidelines, a reasonable approach includes:
Early labor (low risk for immediate delivery):
- Allow clear fluids
- Consider isotonic drinks that provide calories while minimizing gastric volume 3
Active labor or high-risk situations:
- Restrict to ice chips or small sips of water
- Avoid solid foods and fatty liquids
When anesthesia is planned or likely:
- Follow standard preoperative fasting guidelines (clear liquids up to 2 hours, light meal up to 6 hours before) 1
Special Considerations
For patients with dysphagia risk (such as stroke patients), formal swallowing assessment should be completed before resuming oral intake 1, 2.
Conclusion
While traditional NPO policies for laboring patients were strict, current evidence suggests a more balanced approach that considers individual risk factors while allowing reasonable oral intake, particularly clear fluids, during early labor. This approach aims to balance aspiration risk with patient comfort and physiological needs.