There is an association between acidosis, acute physiological dysfunction in the neonate and longer-term neurodevelopment abnormalities. Whether the acidosis is causative or only an associated factor is less certain. Although umbilical artery cord pH has historically been used as a primary marker to hypoxic- ishaemic injury, most term infants with severe acidosis at the time of delivery have an uncomplicated neonatal course, reflecting in part the immense adaptive capacity of the fetus to withstand an asphyxia insult. In a study conducted by King et al (1998) the incidence of neonatal death and neonatal seizures did not increase until a pH < 7.05 was reached (Ben’s lowest recording was pH 6.86).
None of these discussed markers are diagnostic on their own, however, recent clinical studies suggest that high-risk infants are more readily identified by a combination of these (Perlman and Risser, 1996; Perlman, 1999), the more present, the more likely asphyxia has occurred. Therefore, it could be concluded that Ben was at high risk of developing moderate-to-severe hypoxic-ischaemic encephalopathy.
Additionally, in this context, Ben’s abnormal cerebral function results made within six hours after birth, such as through neurological examination and electroencephalography, further indicated that subsequent brain injury was likely to occur (Hellstrom-westas et al, 1995).
Some investigations are helpful in the evaluation of irreversible and massive cerebral injury: EEG, cranial ultrasonography, MRI and CT scan for example. Experiments in the developing brain have shown that asphyxia causes a sequence of abnormalities in the Electroencephalogram (EEG) or Cerebral Function Monitor (CFM) (see profile). Burst suppression, sustained low voltage, and isoelectric activity have all been shown to correlate well with high risk of adverse outcome, with the presence of severely abnormal results on EEG assessments in the first 24 hours appearing to accurately predict negative outcome (Al Naqeeb et al, 1999).
The best indicator that the brain has endured an asphyxial insult is clinical presentation. HIE is subdivided into mild, moderate and severe categories depending on clinical history and neurological examination (see appendix B). Mild HIE carries and excellent prognosis; however, there is an increasing risk of death or severe neurodevelopment abnormalities with more severe encephalopathy (Shankaran et al, 1991.See Ben’s prognosis in profile). If subsequent disability does develop then neuromotor disability may also be associated with intellectual impairment, blindness and epilepsy (Perlman, 1997).
The neuropathology of neonatal HIE varies considerably. In the full term infant pathology is mainly in the cerebral cortex and basal ganglia with the injuries correlating with clinical symptoms such as, disturbances in consciousness, seizures, hypotonia, oculomotor-vestibular abnormalities and feeding difficulties (see Ben’s profile). Persistent feeding difficulties generally due to abnormal tone of the muscles needed for sucking and swallowing suggest significant central nervous system damage.
HIE accounts for approximately 50% of cases of neonatal seizures usually presenting within the first 24 hours of life, most having moderate to severe encephalopathy, and they can be difficult to control pharmacologically (Evans and Levene, 1998). Other insults such as hypoglycaemia and hypocalcaemia may co-exist and trigger post-asphyxial seizures (Refer to Ben’s profile for details of seizure control and hypocalcaemic status).
There is increasing evidence that they have a subtle, but measurable adverse effect on neurodevelopmental progression, and may predispose to cognitive, behavioural or epileptic complications in later life (Levene, 2002).
Unfortunately, EEG monitoring of treated neonates shows that most current treatments are often ineffective in suppressing abnormal electrical activity (Painter et al, 1999). Phenobarbitone remains the mainstay of management in spite of accumulating evidence that it is ineffective as a first line anticonvulsant drug in neonates with seizures in whom the background EEG is significantly abnormal (Boylan et al, 2002. See Ben’s seizure management details). In addition, Levene (2002) states that we do not know of a truly effective neonatal anticonvulsant and phenobarbitone may actually compromise outcome due to its toxicity within the nervous system.
It is currently understood that the severity of insult, seizure activity (particularly if prolonged, frequent and poorly controlled) and duration of abnormalities beyond 7-10 days) are key clinical indicators in poor outcome.
A national review of neonatal care within England undertaken in 2001 highlighted the increasing sophistication of monitoring technology and improved knowledge and identification of fetal and neonatal compromise (British Association of Perinatal Medicine, 2001). However, despite these major advances, HIE remains a serious condition, causing significant mortality and morbidity.
With improvements in techniques and knowledge for accurately predicting outcome, and life support, important ethical issues arise. Ethics is the study of rational processes for determining the most morally desirable action in view of conflicting value choices, it considers competing values in order to obtain the best possible outcome to a given situation (Seedhouse, 1998). The aggressive early management of the severely asphyxiated infant may be counteracted by consideration of eventual outcome, and risk of severe disabilities. Unfortunately, as discussed, the maximal degree of HIE may not be fully apparent until the neonate is a few days old and therefore accurate and truthful prognostication may need to be delayed.
Health professionals face highly emotive quality of life decisions with regards to the withdrawal of intensive care treatment. The ethical dilemma in Ben’s case was that of deciding how aggressively to treat him in view of his poor prognosis and short life expectancy.
The principle of nonmaleficence, or "do no harm," is one of the hallmark
principles of health care and ethics in health care (Beauchamp and Childress, 1994). Also paramount is the goal to restore health and relieve suffering, promoting good, or beneficence. This view is supported by the NMC whose framework governs the maintenance of standards of practice and professional conduct in the interests of patients and society, acting as a guide to ethical practice within nursing.
There are times when members of the health care team or parents perceive these goals as conflicting, or perhaps beyond reach. There was a realisation that continuing treatment may be causing Ben harm in that it was unlikely to restore his health or relieve suffering. It is these times when consideration must be given to withholding and/or withdrawing treatment (Ethics Advisory Committee, 1997), and reorientation of treatment to compassionate care may be acceptable practice.
Health professionals have a moral and legal duty of care but does this mean extending life at any cost? The fact that intensive therapy was initiated does not necessarily mean it should be continued. If judged to be futile then it is accepted, at least in principle, that treatment need not continue (House of Lords, 1994), since it would then neither be beneficent nor non-maleficent.
There is a need to justify Ben’s non-treatment, as being is his “best interests”. Neonates rely on other people’s judgements, (namely their parents, doctors and so on) on perceived quality of future life.
If death is a certain consequence then selective non-treatment could be morally and ethically justified. Handley (2003) asks whether it is it possible for a healthy individual to make a valid judgement on the best interests or quality of life issues for a child, such as Ben, who has no experience of a healthy life, but only knows his own existence and a life that is better than no life at all? When prognosis is poor, but there is still potential for life (albeit short and with serious disabilities), Crawford and Power (2001) believe they should be nurtured to enable them to live to their fullest potential. The sanctity of life view i.e, life at all cost, would see the best interests of the child served by the continuance of life. One could also reason that to selectively withhold or withdraw treatment from infants judged to be ‘different’ could in itself be seen as unethical and discriminatory practice.
Nevertheless, if the child’s life is to be one of suffering and pain, then it could be inferred from the infant’s perspective that life may not be worth living. This may be especially true when life expectancy is short (as with Ben).
To explore this from a more controversial perspective Culyer (1992) states the objective of health care services is to offer maximum benefit to the most people, within the resources available and that it is ethical to be efficient. From this view point, individuals receiving health care should demonstrate better health than if they were not however, if this was at great cost it could deprive the availability of treatment for others (Stevenson and Cooke, 1998). Withdrawing expensive treatment could therefore be described as ethically efficient for the greater good of society.
The decision to withdraw Ben’s intensive care treatment involved: weighing up the judged value of preserving his life, against the suffering that implementing prolonged aggressive and invasive treatment would cause. The withdrawal of intensive care support appeared ironically, to be the lesser of two ‘evils’.
The environment for the care of sick newborns has been directly and extensively changed by the expansion of specialised and highly technical care. The present system of neonatal intensive care is conducted in an environment established on the expectation that these advances can save even the smallest and sickest babies (Graham, 2001).
The evolution of technology has undoubtedly changed the way sick infants are cared for. With developing understanding and advances in technology, nursing and medical interventions have been refined, and nurses working in this area have developed the skills base from which to deliver both technical and practical care.
The advent and aggressive development of the neonatal intensive care system has had a profound effect on the survival rates of large numbers of infants who would otherwise have died. However, as previously discussed, survival is not always without cost. A higher prevalence of cognitive, sensory, motor, and developmental problems have been documented among survivors of neonatal intensive care units (British Association of Perinatal Medicine, 2001). Outcome for such infants largely determined by birth weight, gestational age, clinical course and complications, and by factors from within the neonatal intensive care setting (Blackburn and Vanderburg, 1998).
As the mechanics of providing neonatal intensive care have become more complex and advanced, tremendous attention has been directed toward the effects of the intensive care experience. Developmentally supportive care has evolved in recent years as the focus has shifted from mere survival to survival without neurological impairment. Als and Glickerson, (1998) defines developmentally supportive care as the provision of social interactions and necessary nursing interventions in a fashion that supports the neurodevelopmental and physiological stability of the newborn infant. These interventions include: gently placing the infant in a flexed position to promote containment, clustering therapeutic interventions to promote sleep-wake patterns, supportive holding during and after procedures, bundling, nesting and swaddling infant, reducing light and sound levels (dim lighting/quiet environment), and providing support for parents to pacify, nurture and care for their infants. (See protocol to protect and maintain the neonatal environment – Appendix D).
The environment within a neonatal intensive care unit deviates dramatically from conditions that would be encountered by the normal newborn. Because medically fragile neonates spend prolonged amounts of time in the NICU, the NICU environment must protect sleep, support physiologic stability, and reduce potential adverse effects on the neonate (Lynam, 2003). Although most healthy full-term infants may be able to cope successfully with multiple external stimuli, compromised infants are less likely to tolerate such stressors. Compromised infants may respond to both social interactions and physical interventions with characteristic responses that signal distress or physiological instability.
Developmentally supportive care aims to tailor an infant's environment to reduce external stressors and to base interactions and interventions on the infant's unique behavioral and physiological cues (Taquino and Lockridge, 1999). The introduction of developmentally supportive care has markedly altered nursing management of high-risk newborns. Although further research is warranted, preliminary evidence points to a beneficial effect of this change on patients' developmental outcome (Becker et al, 1991; Als and Glickerson, 1998; Carrier, 2001).
To conclude, this case study has described and analysed the pathophysiology of HIE, exploring the different approaches to diagnosis and grading, and evaluating the importance of early intervention and accurate prognostication in terms of treatment options and eventual outcome. An overview of legal, ethical, professional and the controversial financial implications surrounding treatment withdrawal based on quality of life decisions was provided. Finally, the impact of advances in technology and medical interventions on the neonatal intensive care environment has been emphasised and the implications this has for nursing practice highlighted.
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