NITROUS OXIDE FOR CHILDBIRTH LARRY LEEMAN MD MPH

NITROUS OXIDE FOR CHILDBIRTH LARRY LEEMAN MD MPH ROBYN LAWTON, CNM LAURA MIGLIACCIO, CNM

OBJECTIVES Participants will 1) Understand role of nitrous oxide for labor analgesia and historical context 2) Understand research regarding safety and efficacy for labor analgesia 3) Be familiar with new UNM Labor and delivery guidleline for nitrous in labor

DISCLAIMERS • None • Nitrous equipment is FDA approved

SPECIAL THANKS TO…… Amanda Holbrook, RN Trisha Mondragon, RN Sharon Phelan, MD Eva Szabo, MD Beth Brown, RN Steve Villescas (Safety) Adda Garcia Mc. Donald (Quality)

WHY INTRODUCE NITROUS OXIDE FOR LABOR ? • Increase women’s options beyond epidural, parenteral opiates and “natural” childbirth • Now in use in many medical centers- University of Colorado, UCSF, University of Washington, Brigham and Women’s’ • Increase patient satisfaction with labor and delivery experience • Attract new patients and increase volume of births

AGENDA: NITROUS OXIDE FOR CHILDBIRTH • History • Review of research and side effects • Clinical implementation • UNMH guideline

HISTORY • 1772 -First synthesized • 1881 -Klikovich (Poland) first studied for labor • 1934 -Minnitt (England) invented “gas and air” apparatus

CURRENT NITROUS OXIDE USE AROUND THE WORLD • Canada 40 -45% • Finland 60% • Sweden 65% • UK 50 -75% • US <1% Likis 2014

HOW IT WORKS • Mechanism poorly understood • Works in gray matter of midbrain, induces endorphin, corticotropin, and dopamine release, modulating pain stimuli by way of descending spinal cord nerve pathways, changing perception of the pain. Rosen 2002; Maze 2000

RESEARCH (LIKIS 2014) • “Literature addressing nitrous oxide use in labor includes few studies of good or fair quality” • “Further research is needed across all areas examined including effectiveness, satisfaction, safety and adverse events”

LACK OF STUDY STANDARDIZATION • Differences in concentrations-30 -80% • Differences in inhalation methods (mouthpiece vs mask, continuous vs intermittent) • Comparison groups using other agents (inhaled, opiates) vs no nitrous • Use of different pain measures, most often retrospectively

COCHRANE REVIEW (2012) • 26 studies (2959 women) • 9 of the 26 studies compared nitrous with placebo or no treatment • Women reported less pain intensity (30 -50% less) in nitrous vs placebo groups • More nausea, dizziness and drowsiness reported in nitrous group

NITROUS OXIDE EFFICACY • N= 26 women in early labor, RCT, double-blind • Compared air with 50% nitrous/50% oxygen • Intervention used for 5 consecutive contractions • Almost no difference in pain scores, yet… • Majority of the nitrous group wanted to continue using it once study period over Carstinou et al. (1994). Anesthesiology 80: 30 -5

MATERNAL EXPECTATIONS AND EXPERIENCES • N=98 multips in active labor • RCT, N 2 O vs no N 2 O • Results: Nitrous oxide reduced severity of pain • 98% of intervention group satisfied with method • 80% would request it again Pasha et al. 2012

SAFETY OUTCOMES-REVIEW • No differences in: • Cord blood gases • Apgar score • NICU admission • FHR • Blood loss at delivery • Uterine contractions or labor progress • Mode of delivery • No report on bonding, breastfeeding, and long term infant outcomes Klomp et al (2012)Cochrane Database of Systematic Reviews Likis et al (2014) Anesthesia and Analgesia Rooks, J. (2011). J. Midwifery & women’s Health

OBSTETRIC PAIN RELIEF AND ITS ASSOCIATION WITH REMEMBRANCE OF LABOR PAIN AT 2 MONTHS AND 1 YEAR POSTPARTUM WALLENSTROM ET AL 2006

LABOR PAIN AT 2 MONTHS PP WALLENSTROM ET AL 2006

LABOR PAIN AT 2 MONTHS PP WALLENSTROM ET AL

SIDE EFFECTS Nausea 5 -33% Dizziness 3 -35% Dysphoria 5 -10% Drowsiness 0 -24% Hazy memory 0 -37% Chronic occupational exposure risk

SUMMARY • Despite not being able to quantitate pain relief, many women report positive results using nitrous oxide, and most would choose it again in a subsequent labor. • For some women, nitrous will not provide enough relief, but for others it may be acceptable in exchange for more mobility and less monitoring. • Nitrous oxide is widely used around the world, yet we lack long term data on infant outcomes.

NITROUS OXIDE FOR LABOR ANALGESIA • Pain reduced but still present • Significant anxiolytic • Free to move about • No IV needed • Quick relief • Personal control • No impact on labor progress or pushing • Does not appear to have adverse effects on baby (http: //www. childbirthconnection. org/article. asp? ck=10188#effects)

COLLABORATIVE GUIDELINE • Leadership from all three clinical maternity services • Obstetrical anesthesia • Labor and Delivery Nurse manager and educators • Biomedical, patient safety, pharmacy

PANICKED NEWBORN DIDN’T REALIZE BREATHING WOULD BE ON APGAR TEST

UNMH NITROUS OXIDE GUIDELINE A 50/50 BLEND WITH OXYGEN -USED AS ANALGESIA

UNMH INDICATIONS FOR NITROUS USE • Labor pain relief • PP laceration repair • PP IUD placement • Balloon catheter placement • Manual placenta removal (conscious sedation or regional anesthesia may be preferred) • External cephalic version • IV placement

PRECAUTIONS/CONTRAINDICATIONS • Can’t hold own face mask • Overly sedated, intoxicated or neurologically impaired • Methadone/Buprenorphine users okay if not excessively sedated • Vitamin B 12 deficiency • (ex: strict vegan, Crohn’s disease, or bariatric surgery) • (may confirm normal B 12 levels prior to use) • Category III fetal heart rate

PRECAUTIONS/CONTRAINDICATIONS • Hemodynamic instability/impaired oxygenation • Consult Anesthesia if O 2 Sat<93% • Recent head trauma (w/in 2 wks), increased intraocular pressure, pneumothorax, bowel obstruction, eye surgery, or middle ear surgery requires anesthesiology consult

NITROUS OXIDE USE WITH OTHER ANALGESICS • Do NOT administer nitrous oxide and IV narcotics concurrently • (Wait 1 hour after narcotics before starting nitrous) • No delay in starting IV opiates needed after last nitrous inhalation • No delay in epidural necessary after nitrous oxide unless directed by the Anesthesia

MAY CONSIDER NITROUS OXIDE FOR…. . • Concurrently with local analgesics for laceration repair • For epidural placement with anesthesia approval & management

PATIENT PREPARATION • • Handout information prenatally Assess patient Review contraindications Inform about possible side effects: • nausea, vomiting, dizziness • Initiate Medication “Power Order” • Instruct patient and support people

BEFORE INITIATING ASSESS & DOCUMENT • Patient suitability • Absence of contraindications • Vital signs • O 2 Saturation • Mental status • FHT’s

SET UP BY NURSING • Demand Valve/Keys in Pyxis/medication room • Tanks in R. T. gas room • Connect to wall oxygen and suction • Confirm mask, hoses, and clamps in place before start

IMPORTANT POINTS…. . • ONLY patient may use • Hold over nose/mouth to make seal • Inhale gas 30 seconds before contraction. Full effect takes 50 seconds. May take 3 - 4 UCs to learn the best technique. • Exhale fully into the mask for scavenging • Machine makes hissing sound

• May ambulate with assistance after at least five minutes if stable. • Before moving wait 60 seconds after last inhalation.

ONGOING PATIENT CARE • RN to observe/assess for first 15 minutes • confirm correct usage, effectiveness, and side effects • Vital Signs • routine L&D orders • Fetal monitoring • continuous or IA as indicated • If maternal or fetal wellbeing compromised • discontinue nitrous oxide, notify provider • perform intrauterine resuscitation interventions as needed

EQUIPMENT CARE • Bio-Med will assess every 12 months • Full clean/disinfect occurs after use in room • Clean units will be covered in plastic in medication room

SAFETY • Don’t trip on tubes! • Refer to SDS if exposure occurs • Leaking nitrous can cause altered mental state • (Scavenging system in machine & wall suction) • Share any concerns with Charge RN • QA/Pt Safety Committee will review every 3 months

REFERENCES Barbieri R, Camann W, Mc. Govern C. Nitrous oxide for labor pain. OBG management 2014: 26(12): 10 -12, 14. Berlit S 1, Tuschy B, Brade J, Mayer J, Kehl S, Sütterlin M. Effectiveness of nitrous oxide for postpartum perineal repair: a randomised controlled trial. Eur J Obstet Gynecol Reprod Biol. 2013 Oct; 170(2): 329 -32. Bishop J. Administration of Nitrous oxide in labor: expanding the options for women. Journal of Midwifery and Women’s Health 2007; 52 (3): 308 -309. Leeman L, Fontaine P, King V, Klein MC, Ratcliffe S. The nature and management of labor pain: Part ll. Pharmacologic pain relief. Am Fam Physician 2003; 68: 1115 -20. Likis FE, Andrews JA, Collins MR, Lewis, RM, Seroogy JJ, Starr SA, Walden RR, Mc. Pheeters ML. Nitrous Oxide for the Management of Labor Pain. Comparative Effectiveness Review No. 67. (Prepared by the Vanderbilt Evidence-based Practice Center under Contract No. 290 - 2007 -10065 -I. ) AHRQ Publication No. 12 -EHC 071 -EF. Rockville, MD: Agency for Healthcare Research and Quality. August 2012. Likis FE, Andrews JC, Collins MR, Lewis RM, Seroogy JJ, Starr SA, Walden RR, Mc. Pheeters ML. Nitrous oxide for the management of labor pain: a systematic review. Anesth Analg. 2014 Jan; 118(1): 153 -67. Rooks J. Safety and Risks of nitrous oxide labor analgesia: a review. Journal of Midwifery and Women’s Health 2011; 56(6): 557 -565. Stewart, L. S. , & Collins, M. (2012) Nitrous Oxide as Labor Analgesia: Clinical Implications for Nurses. Nursing for Women’s Health, 2012; 16(5): 398 -408. 16(5)

REFERENCES Carstinou, J. , Levytam, S. , Norman, P. , Daley, D. , Katz, J. , Sandler, A. (1994). Nitrous oxide in early labor safety and analgesic efficacy assessed by a double-blind, placebo-controlled study. Anesthesiology, 80: 30 -35. Collins, M. , Starr, S. , Bishop, J. , Baysinger, C. Nitrous oxide for labor analgesia: expanding analgesic options for women in the United States. Rev Obstet Gynecol. 2012; 5: e 126–e 131. Klomp, T. , Poppel, M. V. , Jones, L. , Lazet, J. , Nisio, M. D. , & Lagro-Janssen, A. L. (2012). Inhaled analgesia for pain management in labour. Cochrane Database of Systematic Reviews, 9. doi: 10. 1002/14651858. CD 009351. pub 2 Maze, M. , & Fucinaga, M. (2000) Recent advances in understanding the action and toxicity of nitrous oxide. Anaesthesia, 55(4), 311 -14. Pasha, H. , Basirat, Z. , Hajahmadi, M. , Bakhtiari, A. , Faramarzi, M. , & Salmalian, H. (2012). Maternal expectations and experiences of labor analgesia with nitrous oxide. Iranian Red Crescent Medical Journal, 14 (12), 792 -92. Rosen, M. A. (2002). Nitrous oxide for relief of labor pain: A systematic review. American Journal of Obstetrics & Gynecology, 186, 110 -126. Su, F. , Wei, X. , Chen, X. , Hu, Z. , &Xu, H. (2002). Clinical study on efficacy and safety of labor analgesia with inhalation of nitrous oxide in oxygen.

THANK YOU