Testimony on Fetal Pain - Julie Ann Griffin, MD
Testimony for the Kansas House of Representatives
Testimony for the Kansas House of Representatives
Committee on Federal and State Affairs
Chairman Steve Brunk
16 February 2011, 1:30pm
Kansas State Capitol Building, Room 346
Julie Ann Griffin, MD
Hospitalist at Labette Health in Parsons, Kansas
Board Certified by the American Board of Internal Medicine
and the American Board of Pediatrics
Licensed by the Kansas State Board of Healing Arts
- Recognition of the Committee for consideration of House Bill No. 2218
- Appreciation of the Committee’s time and attention
- Discussion of personal background and qualifications
- Topics to be discussed: definition of pain, description of the anatomy and physiology of pain, examination of fetus’ developmental abilities with respect to pain, evidence of the fetus’ ability to experience pain, and reviewing the response of the medical community in light of fetal pain and viability research
Definition of Pain
- International Association for the Study of Pain defines pain as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.”
- “The inability to communicate verbally does not negate the possibility that an individual is experiencing pain and is in need of appropriate pain-relieving treatment.”
- It is unquestionably a sensation in a part of parts of the body, but it is also always unpleasant and therefore also an emotional experience.” (emphasis added)
- Being incapable of verbal expression, the human fetus expresses pain through surrogate markers, including anatomical, functional, physiological and behavioral indicators.
- These markers are correlated with the same markers in children and adults.
Anatomy and Physiology of Pain
- Four processes in the sequence of events with respect to pain perception: transduction, transmission, modulation, and perception.
- Transduction of pain starts with a noxious stimulus to the skin or viscera (internal organs). The primary afferent nociceptors (a receptor preferentially sensitive to such stimuli) are activated.
- Nociceptors are specialized to receive energy in various forms: mechanical, chemical, electrical, or thermal.
- Transmission occurs when this information is electrically conducted through the nervous system via three major pathways.
- The information travels through peripheral nerves to interneurons in the spinal cord. These spinal neurons send projections to the brainstem and diencephalon (part of the forebrain that contains important structures such as the thalamus, hypothalamus, posterior portion of the pituitary gland, and pineal gland). Neurons from the brainstem and diencephalon then transmit these signals to the cortex structures, the highest areas of the brain.
- Modulation is the process involving the descending pathways that downregulate this information by the expression of inhibitory neurotransmitters and endogenous opioids, biologically making the stimulus more tolerable.
- Perception is the “feeling” of pain, the subjective sensation thereof, presumably resulting from the concerted activation of the various cortical structures of the brain.
Development of the Fetus’ Ability to Experience Pain
- Nociceptors are present by 7 weeks around the mouth and face and cover the entire body by 20 weeks, and they are more densely configured per square inch on the fetus than on the adult.
- Second order neurons in the spinal cord appear from 10 to 30 weeks gestational age (wga), increasing in anatomical complexity and functional maturation throughout fetal life.
- The neuronal cell types in the fetal brainstem and diencephalon organize and differentiate from the first and into the second trimester; these functional receptors, chemical transmitters, and enzymes are those expressed in the adult human brain.
- The cerebral cortex starts to form at 8-10 wga, and by the 15th wga, the fibers from the pathways below have penetrated into the cortex.
- The modulation or inhibitory pathway does not develop until late in gestation (36-40 wga) so that pain signals are unfiltered, and essentially, uncontrolled, in the human fetus.
Evidence of the Fetus’ Ability to Experience Pain
- Studies demonstrate that fetuses given transfusions through a needle placed through the fetal abdominal wall and into the liver resulted in significantly increased stress hormone production (plasma cortisol, catecholamines, and β-endorphin) by the fetus, and this response was correlated with the duration of the painful stimulation.
- No consistent response was elicited when the non-innervated umbilical cord was used.
- These hormonal responses were reduced when narcotic analgesia was administered directly to the fetus.
- Blood flow to the middle cerebral artery of the brain decreases within seventy seconds after painful stimulation (caused by invasive procedures such as fetal blood sampling, body cavity aspirations, and insertion of feto-amniotic shunts) in fetuses as young as 16 wga.
- Ultrasonographic findings have captured specific fetal movements in response to punctures in utero.
Response of the Medical Community in Light of Fetal Pain and Viability Research
- Maternal anesthesia requires doses toxic to the mother in order to ensure sufficient doses of pain relief to the fetus during a surgical procedure.
- The fields of pediatric anesthesiology and surgery have gone from withholding any analgesia to neonates undergoing major surgery in the 1980s to recognized subspecialties requiring their own certifications by national organizations due to the complexities of providing anesthesia and surgical treatment to neonates.
- Fetal anesthesiology and fetal surgery are rapidly growing fields of medicine appearing throughout children’s hospitals across the nation with the goal of providing pain- and stress-free environments for fetuses undergoing invasive procedures.
- The pediatric subspecialty of neonatology has been able to lower the limits of viability of a preterm neonate from twenty-eight weeks gestation age in 1973 (year of the Roe v Wade decision) to twenty three weeks gestational age today.
- Neonatologists now use well-researched and validated tools to measure and adequately treat pain for infants in neonatal intensive care units such as the premature infant pain profile.
- Pain is both a sensory and emotional experience.
- Four major pathways are involved in order to perceive pain.
- The human fetus develops aspects of pain architecture as early as 6-7 wga, and these features constitute a developed and coordinated pain response to noxious stimuli by twenty to twenty-two weeks gestational age.
- The human fetus is unable to modulate or inhibit these responses until late in gestation.
- Human fetuses produce significantly increased stress hormone responses, experience changes in direction of blood-flow to the brain, and exhibit specific movements away from pain, while undergoing invasive medical procedures as early as 16 wga.
- Physicians and other researchers in the fields of medicine and surgery have made considerable strides in their understanding of fetal pain in the last thirty years.
- Appreciation for both the mother and the fetus as two separate human beings capable of feeling pain and for whom I provide medical care calls me to support HB No. 2218.
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